JP4495980B2 - Stencil printing machine - Google Patents

Description

  The present invention relates to a stencil printing apparatus, and more particularly to a peeling mechanism that peels a sheet from the outer peripheral surface of a plate cylinder.

  A plate cylinder made by winding a resin or metal mesh mesh screen around the circumference of a cylindrical porous support plate, and a thermoplastic resin film and Japanese paper fiber or synthetic fiber or Japanese paper fiber and synthetic fiber. Using a master with a laminate structure formed by laminating the material, the thermoplastic resin film surface of the master is heated and perforated by a heating element, wound around a plate cylinder, and from an ink supply means provided inside the plate cylinder While supplying ink to the inner peripheral surface of the plate cylinder, the ink is continuously pressed from the plate cylinder opening and the master punching portion by continuously pressing the paper against the master made on the outer peripheral surface of the plate cylinder by a pressing member such as a press roller. A heat-sensitive digital stencil printing apparatus is known which performs printing by transferring the ink onto a paper.

  In this stencil printing apparatus, the printed paper is peeled off from the plate-making master on the outer peripheral surface of the plate cylinder with a peeling claw as a peeling member, and discharged onto a paper discharge tray provided in a paper discharge unit. The peeling claw is disposed in the vicinity of the outer peripheral surface of the plate cylinder so that a slight gap is formed between the tip and the master so as not to damage the master that has been made on the outer peripheral surface of the plate cylinder. The paper is peeled off from the outer peripheral surface of the plate cylinder by forcibly intervening between the leading margin of the plate and the master that has been made.

  However, if there is a solid image portion on the plate-making image formed on the master, the adhesive force of the ink acting between the paper and the master is extremely increased, and the paper is removed from the plate cylinder by the peeling claw. The paper cannot be peeled off from the master, and the paper remains stuck on the master or the paper is caught on the peeling claw, so that the peeling operation is not performed reliably, and a problem of winding up occurs.

  In order to prevent the occurrence of this roll-up, an air discharge port is provided at the tip of the peeling claw, and air is discharged from this discharge port between the paper and the master. For example, “Patent Document 1” and “Patent Document 2” disclose techniques for preventing the occurrence of winding by peeling a sheet from the outer peripheral surface of the cylinder.

  On the other hand, in the above-described stencil printing, recently, double-sided printing, in which printing is performed on both sides of paper, has been frequently performed in order to reduce paper consumption, document storage space, and the like. In this double-sided printing, the paper loaded on the paper feed unit is passed through the printing unit, printed on one side of the paper, turned over, and then passed again through the printing unit, and printed on the other side of the paper. Although a method for obtaining a double-sided printed product by performing the above-described process has been adopted, it is troublesome to re-align the discharged paper and set it again in the paper feed unit.

  Therefore, the applicant of the present application stacks the printing unit, the auxiliary tray for double-sided printing that temporarily stores the printed sheet on the surface of which the printed image is formed, and the sheet on which the printed image is formed. It has a paper discharge tray and a switching member that passes the paper that has passed through the printing section to either the auxiliary tray or the paper discharge tray, and can easily switch between single-sided printing and single-step double-sided printing. A double-sided printing apparatus is proposed in “Patent Document 3”.

No. 4-15509 JP 11-334191 A JP 2003-200355 A

  In the techniques disclosed in “Patent Document 1” and “Patent Document 2”, the timing at which air is discharged from the leading edge of the peeling claw is in the vicinity of the leading edge of the paper, so that the paper has a solid image portion covering almost the entire surface. Or when the paper has a solid image part extending rearward of the central part in the transport direction, the leading edge of the paper is peeled off by the air discharged from the peeling claw, but the trailing edge of the paper It peels off to the paper when the paper is peeled and conveyed while in contact with the peeling claw because it adheres to the master on the outer periphery of the plate cylinder due to the adhesive force of the ink adhering to the solid image area. There is a problem that a nail mark remains and an abnormal image or dirt remains, and further, there is a problem that a paper sticks into a peeling nail and causes a conveyance jam. This often occurs when a sheet having a size exceeding A4 is passed or when a sheet having a size smaller than A4 is passed so that the longitudinal direction thereof is the sheet transport direction.

  In the double-sided printing apparatus disclosed in “Patent Document 3”, the single-sided printing operation is performed in substantially the same manner as the stencil printing apparatus disclosed in “Patent Document 1” and “Patent Document 2”. Done in the process.

  First, the first sheet is fed from the sheet feeding unit, and the first plate making image and the first sheet corresponding to the surface print image in the divided plate making master wound around the plate cylinder are pressed. Pressing with a member creates a surface printed paper. The first sheet that has become the surface printed sheet is peeled off from the plate cylinder by the switching member functioning as the first peeling member and guided to the auxiliary tray.

  Next, the second sheet is fed from the sheet feeding unit, and the first plate-making image of the divided plate-making master and the second sheet are pressed by the pressing member to create the next surface-printed sheet. The second sheet that has been printed on the front side is peeled off from the plate cylinder by the switching member and guided to the auxiliary tray. During the surface printing process of the second sheet, the sheet re-feeding unit operates to feed the first sheet from the auxiliary tray toward the printing unit.

  The first sheet is fed at a timing coincident with the second plate-making image corresponding to the back-side printed image of the divided plate-making masters wound on the plate cylinder, and is applied to the outer surface of the plate cylinder by the pressing member. The back image is printed by being pressed. The first sheet, which has been printed on both sides and has become a printed sheet, is peeled off from the outer peripheral surface of the plate cylinder by a peeling claw that functions as a second peeling member, and sent to the paper discharge unit. Thereafter, this operation is repeated, and one double-sided printed paper is produced by one rotation of the plate cylinder.

  When this double-sided printing apparatus is used, the paper is peeled off by the peeling claw from the front end position of the plate-making master during single-sided printing, and from the front end of the second plate-making image of the divided plate-making master during double-sided printing. Is called. As described above, in this double-sided printing apparatus, the peeling timing by the peeling nail is different between single-sided printing and double-sided printing. Therefore, the technology disclosed in "Patent Document 1" or "Patent Document 2" is applied to this double-sided printing apparatus. Even if the single-sided printing and the double-sided printing are performed, a good peeling operation cannot be performed, and the occurrence of winding cannot be completely prevented.

  In addition, this double-sided printing apparatus has the same problems as the above-described single-sided printing apparatus during single-sided printing, and during double-sided printing (small-size paper is passed with its short side as the paper transport direction during double-sided printing. ) May have the same problem as the above-described single-sided printing apparatus.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a stencil printing apparatus that solves the above-described problems and can satisfactorily peel from a plate cylinder even with a sheet having a solid image portion.

First aspect of the present invention, a printing unit having a pressing means to press the sheet against the plate cylinder and the plate cylinder, a sheet feeding unit for feeding toward the sheet to the printing unit, in the printing unit In the stencil printing apparatus having a paper discharge unit for discharging printed paper that has been printed, the outer periphery of the outer periphery of the plate cylinder to release the paper pressed on the outer peripheral surface of the plate cylinder by the pressing means. A peeling member having a jet port for jetting air between the surface and the paper, and an air supply means for supplying air to the peeling member, the peeling member corresponding to the leading edge of the paper. 1 position, Ri jettable der air from the spout in a second position located downstream in the sheet conveying direction than the first position of the paper, the paper conveying direction length of the sheet is predetermined If greater than the value, the peeling member is in the first position. And the second position, which is approximately the middle of the length of the paper in the paper conveyance direction, ejects air from the outlet, and the length of the paper in the paper conveyance direction is less than a predetermined value. The peeling member ejects air from the ejection port only at the first position .

According to a second aspect of the present invention, there is provided a printing unit having a plate cylinder and a pressing unit that presses the sheet against the plate cylinder, a sheet feeding unit that feeds the sheet toward the printing unit, and printing in the printing unit. In the stencil printing apparatus having a paper discharge section for discharging printed paper that has been subjected to printing, the outer peripheral surface to peel the paper pressed on the outer peripheral surface of the plate cylinder by the pressing means from the outer peripheral surface of the plate cylinder And a separation member having a spout for ejecting air toward the sheet, and air supply means for supplying air to the separation member, wherein the separation member corresponds to the first end of the sheet. And a second position located downstream of the first position of the sheet in the sheet conveyance direction, air can be ejected from the ejection port, and the print image formed on the sheet is a solid image The release member is the first Position and by ejecting air from the jetting port in both the second position is a corresponding position to the solid image portion, when the print image does not have a solid image portion, the peeling member is the Air is ejected from the ejection port only at the position of 1.

According to a third aspect of the present invention, there is provided a printing unit having a plate cylinder and a pressing unit that presses the sheet against the plate cylinder, a paper feeding unit that feeds the sheet toward the printing unit, and printing in the printing unit. In the stencil printing apparatus having a paper discharge section for discharging printed paper that has been subjected to printing, the outer peripheral surface to peel the paper pressed on the outer peripheral surface of the plate cylinder by the pressing means from the outer peripheral surface of the plate cylinder And a separation member having a spout for ejecting air toward the sheet, and air supply means for supplying air to the separation member, wherein the separation member corresponds to the first end of the sheet. And a second position located downstream of the first position of the paper in the paper conveyance direction, air can be ejected from the ejection port, and the length of the paper in the paper conveyance direction is greater than a predetermined value. Is larger, the peeling member is in the first position. The ejected air from the jetting port in both the second position is substantially located in the middle of the sheet conveying direction length paper and the paper conveyance direction length of the sheet is equal to or lower than a predetermined value If the printed image formed on the sheet has a solid image portion, the peeling member ejecting air from said ejection port in both the second position the corresponding to the solid image portion and the first position When the length of the paper in the paper conveyance direction is equal to or less than a predetermined value and the printed image does not have a solid image portion, the peeling member ejects air from the ejection port only at the first position. It is characterized by doing.

According to a fourth aspect of the present invention, there is provided a printing unit having a plate cylinder and a pressing unit that presses the sheet against the plate cylinder, a sheet feeding unit that feeds the sheet toward the printing unit, and printing in the printing unit. A paper discharge unit that discharges printed paper that has been printed, an auxiliary tray that temporarily stores printed paper on the surface of which the printed image is formed in the printing unit during double-sided printing, and the auxiliary tray during double-sided printing Refeeding means for refeeding the surface printed paper stored on the paper toward the printing unit, and peeling the surface printed paper that has passed through the printing unit during duplex printing from the outer peripheral surface of the plate cylinder A first peeling member that guides to the auxiliary tray, and a second peeling member that peels the printed paper that has passed through the printing unit from the outer peripheral surface of the plate cylinder and guides it to the paper discharge unit. When printing on both sides, the length of the master The plate-making master having the first plate-making image corresponding to the surface image and the second plate-making image corresponding to the back-side image, and the plate-making master having the third plate-making image for single-sided printing formed at the time of single-sided printing are used as the plate cylinder. In the stencil printing apparatus that can be wound on and switched between single-sided printing and double-sided printing , the first peeling member is configured to peel off the surface-printed paper from the outer peripheral surface of the plate cylinder during double-sided printing. In addition to having a first jet outlet that blows air between the outer peripheral surface and the surface-printed paper, the second peeling member is intended to peel the printed paper from the outer peripheral surface during double-sided printing and single-sided printing. An air supply means for supplying air to the first peeling member and the second peeling member; the first peeling member having a second jet nozzle for jetting air between the outer peripheral surface and the printed paper; For the surface printed In a first position corresponding to the leading edge of the printed sheet, the second peeling member blows air from each of the outlets in a second position corresponding to the leading edge of the printed paper, and the first peeling member is printed on the surface. In a third position located downstream of the first position of the paper in the paper conveyance direction, the second peeling member is located fourth downstream of the second position of the printed paper in the paper conveyance direction. When the length of the paper in the paper conveyance direction is larger than a predetermined value during single-sided printing, the second peeling member is moved to the second position and the paper conveyance of the paper. When air is ejected from the second ejection port at both the fourth position, which is the middle position in the direction length, and the length of the paper in the paper transport direction is less than a predetermined value during single-sided printing, 2 The peeling member is in the second position When the air is ejected from the second ejection port and the length of the paper in the paper conveyance direction is larger than a predetermined value during double-sided printing, the first peeling member has the first position and the length of the paper in the paper conveyance direction. The air is ejected from the first ejection port at both the third position, which is a substantially middle position, and the second peeling member is approximately at the middle of the second position and the length of the sheet in the sheet conveyance direction. When the length of the paper in the paper transport direction is less than or equal to a predetermined value during double-sided printing, the first peeling member is moved to the first position at both the fourth position and the fourth position. And the second peeling member ejects air from the second ejection port only at the second position .

According to a fifth aspect of the present invention, there is provided a printing unit having a plate cylinder and a pressing unit that presses the sheet against the plate cylinder, a paper feeding unit that feeds the sheet toward the printing unit, and printing in the printing unit. A paper discharge unit that discharges printed paper that has been printed, an auxiliary tray that temporarily stores printed paper on the surface of which the printed image is formed in the printing unit during double-sided printing, and the auxiliary tray during double-sided printing Refeeding means for refeeding the surface printed paper stored on the paper toward the printing unit, and peeling the surface printed paper that has passed through the printing unit during duplex printing from the outer peripheral surface of the plate cylinder A first peeling member that guides to the auxiliary tray, and a second peeling member that peels the printed paper that has passed through the printing unit from the outer peripheral surface of the plate cylinder and guides it to the paper discharge unit. When printing on both sides, the length of the master The plate-making master having the first plate-making image corresponding to the surface image and the second plate-making image corresponding to the back-side image, and the plate-making master having the third plate-making image for single-sided printing formed at the time of single-sided printing are used as the plate cylinder. In the stencil printing apparatus that can be wound on and switched between single-sided printing and double-sided printing , the first peeling member is configured to peel off the surface-printed paper from the outer peripheral surface of the plate cylinder during double-sided printing. In addition to having a first jet outlet that blows air between the outer peripheral surface and the surface-printed paper, the second peeling member is intended to peel the printed paper from the outer peripheral surface during double-sided printing and single-sided printing. An air supply means for supplying air to the first peeling member and the second peeling member; the first peeling member having a second jet nozzle for jetting air between the outer peripheral surface and the printed paper; For the surface printed In a first position corresponding to the leading edge of the printed sheet, the second peeling member blows air from each of the outlets in a second position corresponding to the leading edge of the printed paper, and the first peeling member is printed on the surface. In a third position located downstream of the first position of the paper in the paper conveyance direction, the second peeling member is located fourth downstream of the second position of the printed paper in the paper conveyance direction. In the case where the third printing image corresponding to the third plate-making image formed on the sheet at the time of single-side printing has a solid image portion, the second peeling member can When air is ejected from the second ejection port at both the second position and the fourth position corresponding to the solid image portion, and the third print image does not have a solid image portion during single-sided printing. The second peeling member is the second Air is ejected from the second ejection port only at the position 2 and both the first print image corresponding to the first plate-making image formed on the paper during double-sided printing and the second print image corresponding to the second plate-making image are both present. In the case of having a solid image portion, the first peeling member ejects air from the first ejection port at both the first position and the third position corresponding to the solid image portion. The second peeling member ejects air from the second outlet at both the second position and the fourth position corresponding to the solid image portion, and the solid image portion of the first print image is displayed during duplex printing. When the second print image has no solid image portion, the first peeling member is the first jet at both the first position and the third position corresponding to the solid image portion. Air is ejected from the outlet and the second peeling member is in the second position. In the case where only the second ejection port ejects air from the second ejection port and the first print image does not have a solid image portion at the time of double-sided printing, the first peeling member has a solid image portion. Air is ejected from the first jet only at the first position, and the second peeling member is air from the second jet at both the second position and the fourth position corresponding to the solid image portion. When the first print image and the second print image do not have a solid image portion at the time of double-sided printing, the first peeling member jets air from the first outlet only at the first position. In addition, the second peeling member is characterized in that air is ejected from the second ejection port only at the second position .

According to a sixth aspect of the present invention, there is provided a printing unit having a plate cylinder and a pressing unit that presses the sheet against the plate cylinder, a paper feeding unit that feeds the sheet toward the printing unit, and printing in the printing unit. A paper discharge unit that discharges printed paper that has been printed, an auxiliary tray that temporarily stores printed paper on the surface of which the printed image is formed in the printing unit during double-sided printing, and the auxiliary tray during double-sided printing Refeeding means for refeeding the surface printed paper stored on the paper toward the printing unit, and peeling the surface printed paper that has passed through the printing unit during duplex printing from the outer peripheral surface of the plate cylinder A first peeling member that guides to the auxiliary tray, and a second peeling member that peels the printed paper that has passed through the printing unit from the outer peripheral surface of the plate cylinder and guides it to the paper discharge unit. When printing on both sides, the length of the master The plate-making master having the first plate-making image corresponding to the surface image and the second plate-making image corresponding to the back-side image, and the plate-making master having the third plate-making image for single-sided printing formed at the time of single-sided printing are used as the plate cylinder. In the stencil printing apparatus that can be wound on and switched between single-sided printing and double-sided printing , the first peeling member is configured to peel off the surface-printed paper from the outer peripheral surface of the plate cylinder during double-sided printing. In addition to having a first jet outlet that blows air between the outer peripheral surface and the surface-printed paper, the second peeling member is intended to peel the printed paper from the outer peripheral surface during double-sided printing and single-sided printing. An air supply means for supplying air to the first peeling member and the second peeling member; the first peeling member having a second jet nozzle for jetting air between the outer peripheral surface and the printed paper; For the surface printed In a first position corresponding to the leading edge of the printed sheet, the second peeling member blows air from each of the outlets in a second position corresponding to the leading edge of the printed paper, and the first peeling member is printed on the surface. In a third position located downstream of the first position of the paper in the paper conveyance direction, the second peeling member is located fourth downstream of the second position of the printed paper in the paper conveyance direction. When the length of the paper in the paper conveyance direction is larger than a predetermined value during single-sided printing, the second peeling member is moved to the second position and the paper conveyance of the paper. In the case where air is ejected from the second ejection port at both the fourth position, which is a substantially middle position in the direction length, and the length in the sheet conveyance direction of the sheet is equal to or less than a predetermined value during single-side printing, Third product formed on paper When the third print image corresponding to the plate image has a solid image portion, the second peeling member is air from the second jet nozzle at both the second position and the fourth position corresponding to the solid image portion. When the length of the sheet in the paper conveyance direction is equal to or less than a predetermined value during single-sided printing, and the third print image does not have a solid image portion, the second peeling member is in the second position. Only when the air is blown out from the second outlet and the length of the paper in the paper transport direction is larger than a predetermined value during double-sided printing, the first peeling member has the first position and the length of the paper in the paper transport direction. The air is ejected from the first ejection port at both the third position, which is a substantially middle position, and the second peeling member is approximately at the middle of the second position and the length of the sheet in the sheet conveyance direction. Air is ejected from the second jet outlet at both the fourth position and the position. The first print image corresponding to the first plate-making image formed on the paper and the second print image corresponding to the second plate-making image when the length in the paper transport direction of the paper is equal to or smaller than a predetermined value during duplex printing. When both have a solid image part, the first peeling member ejects air from the first outlet at both the first position and the third position corresponding to the solid image part. At the same time, the second peeling member ejects air from the second outlet at both the second position and the fourth position corresponding to the solid image portion, and the length of the sheet in the sheet conveyance direction during double-sided printing. And when the first print image has a solid image portion and the second print image does not have a solid image portion, the first peeling member has the first position and the solid image portion. The first jet at both the image portion and the corresponding third position. When the air is ejected from the mouth and the second peeling member ejects air from the second ejection port only at the second position, the length of the sheet in the sheet conveyance direction is equal to or less than a predetermined value during duplex printing. When the print image does not have a solid image portion and the second print image has a solid image portion, the first peeling member ejects air from the first ejection port only at the first position. The second peeling member ejects air from the second outlet at both the second position and the fourth position corresponding to the solid image portion, and the length of the sheet in the sheet conveyance direction is large during duplex printing. When the first print image and the second print image do not have a solid image portion when the value is equal to or less than the predetermined value, the first peeling member ejects air from the first ejection port only at the first position. In addition, the second peeling member is in the second position only at the second position. It is characterized by ejecting air from the outlet .

  According to the present invention, air is ejected from the ejection port of the peeling member at the first position corresponding to the leading edge of the sheet and the second position located downstream of the first position in the sheet transport direction. Even if it has a solid image part that extends to the rear side of the entire surface or the center in the paper transport direction, the paper adhered to the master on the outer periphery of the plate cylinder by the adhesive force of the ink A good printed matter can be obtained by preventing the occurrence of the trouble that the paper can be peeled off and the trouble that the nail mark stains on the paper or the paper gets stuck in the peeling member and causes the conveyance jam.

  According to the present invention, when printing on one side, from the second peeling member at a position corresponding to the leading edge of the paper, when printing on both sides, from the first peeling member at a position corresponding to the leading edge of the paper when printing on the front surface, and at the leading edge of the paper when printing on the back side Since air is ejected from the second peeling member at a position corresponding to the portion, it is possible to prevent the paper from being rolled up on the plate cylinder and perform good peeling in both single-sided printing and double-sided printing. In addition, a good printed matter can be obtained both in single-sided printing and double-sided printing, and a good printing state can be maintained.

  FIG. 1 is a schematic front view of a stencil printing apparatus 1 adopting the first embodiment of the present invention. In FIG. 1, a stencil printing apparatus 1 includes a printing unit 2, a plate making unit 3, a paper feeding unit 4, a plate discharging unit 5, a paper discharging unit 6, an image reading unit 7, and the like.

The printing unit 2 disposed almost at the center of the apparatus main body 8 includes a plate cylinder 9, an ink supply unit 10, a press roller 11 as a pressing unit, and the like.
The plate cylinder 9 includes a pair of end plates 13a and 13b (only one is shown in FIG. 1, see FIG. 2) rotatably supported by a support shaft 12 also serving as an ink supply pipe, and outer peripheries of the end plates 13a and 13b. It is mainly composed of a porous support plate 9a wound around the surface, and is driven to rotate clockwise in FIG. 1 by a plate cylinder driving means 58 described later. A plurality of small holes for supplying ink to the ink supply means 10 are formed on the surface of the support shaft 12, and the end plates 13a and 13b are rotatably supported by the support shaft 12 via bearings (not shown). Has been.

  The porous support plate 9a formed of a stainless steel thin plate or the like has an opening portion having a large number of openings and a non-opening portion, and the circumferential length of the opening portion is A3 size. It is formed in a length that allows printing on a sheet of paper. A stage portion 14 having a plane parallel to one generatrix of the plate cylinder 9 is disposed in the non-opening portion, and an openable / closable clamper 15 for locking a tip of a master 26 described later on the upper surface of the stage portion 14. Is arranged. Further, on the outside of the opening portion of the porous support plate 9a, about 1 to 3 layers of mesh screen (not shown) made of polyester or stainless steel fine wires are wound.

  An ink supply means 10 having an ink roller 16, a doctor roller 17, and the like is disposed inside the plate cylinder 9 and below the support shaft 12. The ink roller 16 is rotatably supported between a pair of side plates (not shown) fixed on the support shaft 12 between the end plates 13a and 13b, and is driven to rotate in the same direction as the plate cylinder 9 by a driving means (not shown). The The doctor roller 17 is disposed between the side plates so that its peripheral surface is close to the peripheral surface of the ink roller 16, and is rotated in a direction opposite to that of the ink roller 16 by a driving means (not shown). In the vicinity of the ink roller 16 and the doctor roller 17, an ink reservoir 18 having a wedge-shaped cross section is formed by the ink supplied from the support shaft 12.

  As shown in FIG. 2, a gear 59 centered on the support shaft 12 is fixed to the outside of one end plate 13 a, and a tip portion (not shown) of the support shaft 12 penetrates the gear 59 and the apparatus main body 8. Are supported by a side plate (not shown). A handle (not shown) for carrying the plate cylinder 9 is attached to the support shaft 12 so as to straddle the plate cylinder 9 in the axial direction outside each end plate 13a, 13b, and the other end plate 13b side is illustrated. An ink pack (not shown) for replenishing the ink supplied to the support shaft 12 is attached to the side plate of the handle. The plate cylinder 9 is configured such that the above-described handle (not shown) can be engaged with a rail member (not shown) of the apparatus main body 8 and can be detached from the apparatus main body 8 by being extracted in the direction indicated by the white arrow in FIG. It is configured.

  A dog 60 is attached near the outer peripheral edge of one end plate 13a, and a home position sensor 61 is provided on the circular orbit of the dog 60 that moves as the plate cylinder 9 rotates. The home position sensor 61 detects the dog 60 when the plate cylinder 9 occupies the home position, and the detection signal is sent to the control means 74 described later.

  A support shaft 62 that is rotatably supported by the apparatus main body 8 is disposed in the vicinity of the gear 59. A gear 63 and a timing pulley 64 that mesh with the gear 59 are integrally attached to the support shaft 62. ing. The timing pulley 64 is drivingly connected to a pinion 66 fixed to an output shaft 65a of a plate cylinder drive motor 65 attached to the apparatus main body 8 by a timing belt 67, and an encoder 68 is attached to the output shaft 65a. The plate cylinder drive motor 65 detects the rotation angle of the encoder 68 by a pulse detection sensor 69 as a plate cylinder angle detection means attached to the apparatus main body 8, and the detected angle signal is sent through a pulse counter and a comparator (not shown). This is input to the control means 74 described later.

  With the configuration described above, the rotational force of the plate cylinder drive motor 65 is transmitted to the support shaft 62 through the pinion 66, the timing belt 67, and the timing pulley 64, and the rotational force of the support shaft 62 is transmitted through the gear 63 and the gear 59. The plate cylinder 9 is rotationally driven by being transmitted to the cylinder 9. Each of these gears 59 and 63, the support shaft 62, the timing pulley 64, the plate cylinder driving motor 65, the pinion 66, and the timing belt 67 constitute a plate cylinder driving means 58.

  A press roller 11 is disposed below the plate cylinder 9. The press roller 11 is rotatably supported at both ends of a core portion between a pair of press roller arms 19, and its outer peripheral surface is separated from the outer peripheral surface of the plate cylinder 9 by a press roller swinging means (not shown). And a pressing position indicated by a two-dot chain line in FIG. 1 where the outer peripheral surface is pressed against the outer peripheral surface of the plate cylinder 9 with a predetermined pressing force.

  A plate making unit 3 is disposed on the upper right side of the printing unit 2. The plate making unit 3 is configured as a unit having a master storage member 20, a platen roller 21, a thermal head 22, a master cutting means 23, a master transport roller pair 24, 25, and the like, and is integrally attached to and detached from the apparatus main body 8. It is configured to be possible.

  The master storage member 20 includes a pair of master roll holding members 20a and a pair of support members 20b each having a disk shape, and a master roll 27 formed by winding the master 26 in a roll shape is rotatable and detachable. Support freely.

  A platen roller 21 and a thermal head 22 are disposed on the downstream side of the master storage member 20 in the master conveyance direction. The platen roller 21 is rotatably supported on a side plate (not shown) of the plate making unit 3 and is driven to rotate by a stepping motor 28. A thermal head 22 having a large number of heat generating elements on its upper surface is provided on a side plate (not shown) of the plate making unit 3, and its upper surface is pressed against the outer peripheral surface of the platen roller 21 by an urging force of an urging means (not shown).

  Master cutting means 23 is disposed downstream of the platen roller 21 and the thermal head 22 in the master conveyance direction. The master cutting means 23 having a fixed blade and a movable blade has a known configuration in which the master 26 is cut when the movable blade moves up and down or rotates relative to the fixed blade fixed to the plate making unit 3.

  Master transport roller pairs 24 and 25 are disposed downstream of the master cutting means 23 in the master transport direction. Each of the master conveying roller pairs 24 and 25 includes a driving roller that is rotationally driven in synchronization by a driving unit (not shown), and a driven roller that is pressed against each driving roller by an urging unit (not shown). A master guide plate is disposed between each of the master transport roller pairs 24 and 25 and downstream of the master transport roller pair 25 in the master transport direction.

A sheet feeding unit 4 is disposed below the plate making unit 3. The paper feed unit 4 includes a paper feed tray 29, a paper feed roller 30, a separation roller 31, a separation roller 32, a registration roller pair 33, and the like.
A paper feed tray 29 on which a large number of sheets P are stacked is supported by the apparatus main body 8 so as to be movable up and down, and is moved up and down by lifting means (not shown). The paper feed tray 29 is provided with a plurality of paper size detection sensors 34 that detect the size of the stacked paper P and a pair of side fences that guide the paper P from the width direction. Each sensor 34 is composed of a reflective sensor, and a detection signal from each sensor 34 is sent to a control means 74 described later. In this stencil printing apparatus 1, since the plate cylinder 9 can perform printing on the paper P having the maximum A3 size, the size of the paper P that can be stacked on the paper feed tray 29 is also set to the maximum A3 size. It is configured.

  A paper feed roller 30 having a high frictional resistance member on the surface is disposed above the paper feed tray 29. Similarly, a separation roller 31 having a high frictional resistance member on the surface is disposed on the downstream side in the paper transport direction. It is installed. The paper feed roller 30 is in pressure contact with the paper P on the paper feed tray 29 with a predetermined pressure, and the paper feed roller 30 and the separation roller 31 are connected by a driving force transmission means (not shown). Thus, they are rotationally driven in synchronization with each other in the clockwise direction in FIG. The separation roller 32 is disposed in pressure contact with the separation roller 31 with a predetermined pressure contact force, and is configured to be intermittently rotated clockwise in FIG.

  A registration roller pair 33 is disposed downstream of the separation roller 31 and the separation roller 32 in the sheet conveyance direction. The registration roller pair 33 composed of a driving roller and a driven roller transmits the rotational driving force from the plate cylinder driving means 58 by a driving force transmitting means (not shown) such as a gear or a cam so that the driving roller is synchronized with the plate cylinder 9. The paper P is fed toward the printing unit 2 by the driven roller that is rotated at the predetermined timing and is in pressure contact with the driving roller.

A plate discharging unit 5 is disposed on the upper left side of the printing unit 2. The plate removal unit 5 includes an upper plate removal member 35, a lower plate removal member 36, a plate removal box 37, a compression plate 38, and the like.
The upper plate discharging member 35 has a driving roller, a driven roller, an endless belt, and the like, and the endless belt moves in the direction of the arrow in FIG. The lower plate discharging member 36 configured in the same manner as the upper plate discharging member 35 is driven to rotate when the driving force of the upper plate discharging member 35 is transmitted, and the endless belt moves in the direction of the arrow in FIG. The lower plate removal member 36 is configured to be movable by a moving means (not shown), and selectively occupies the position shown in the figure and the position where a part of the endless belt abuts the outer peripheral surface of the plate cylinder 9.

  A plate removal box 37 for storing a used master therein is configured to be detachable from the apparatus main body 8. The compression plate 38 for compressing the used master conveyed into the plate release box 37 by the upper plate release member 35 and the lower plate release member 36 has a position indicated by a solid line and a position indicated by a two-dot chain line in FIG. Move up and down.

A paper discharge unit 6 is disposed below the plate discharge unit 5. The paper discharge unit 6 includes a paper discharge conveyance member 39, a paper discharge tray 40, and the like.
The paper discharge conveying member 39 includes a driving roller, a driven roller, an endless belt, a suction fan, and the like, and sucks the printed paper P onto the endless belt by the suction force of the suction fan, and is driven by a driving unit (not shown). The printed paper P is conveyed in the direction indicated by the arrow in FIG.

  A paper discharge tray 40 on which the printed paper P conveyed by the paper discharge conveying member 39 is stacked is composed of a pair of side fences movable in the paper width direction and one end fence movable in the paper conveyance direction. And have.

  An image reading unit 7 is disposed on the upper part of the apparatus main body 8. The image reading unit 7 includes a contact glass 41 on which a document is placed, a pressure plate 42 provided so as to be able to contact and separate from the contact glass 41, a reflection mirror for scanning and reading a document image, a fluorescent lamp, and the like. 43, a lens 44 for focusing the scanned image, an image sensor 45 such as a CCD for processing the focused image, and the like. A known ADF unit 46 is disposed above the pressure plate 42.

  A peeling member 47 for peeling the printed paper P from the outer peripheral surface of the plate cylinder 9 is disposed in the vicinity of the outer peripheral surface of the plate cylinder 9 and between the discharge plate unit 5 and the paper discharge unit 6. Has been. As shown in FIG. 3, the peeling member 47 has a square pipe shape with both ends opened, and one end side of the peeling member 47 is attached to a support shaft 47 a that is swingably supported by the apparatus body 8. The other end side of the peeling member 47 is formed so as to be gradually narrowed from about the middle, and the tip end portion 47b is formed so as to protrude from the opening 47c which is a jet port.

  The peeling member 47 is swung by a swinging means (not shown), and the tip 47b is located at the position shown in FIG. 1 where the tip 47b is close to the outer peripheral surface of the plate cylinder 9, and the tip 47b is used to avoid obstacles such as the clamper 15. It selectively occupies a position away from the outer peripheral surface of the body 9. The swinging means (not shown) transmits the driving force from the plate cylinder driving means 58 by the driving force transmission means (not shown), and swings the peeling member 47 in synchronization with the rotation of the plate cylinder 9.

  An air supply means 48 is connected to the peeling member 47. The air supply means 48 includes a cylinder 49, a piston 50 that can reciprocate inside the cylinder 49, an air hose 51 having one end connected to the air discharge port 49 a of the cylinder 49 and the other end connected to one end of the peeling member 47, a rotating plate 52, mainly composed of a link 53 and the like, one end of which is attached to the periphery of the rotating plate 52 and the other end is attached to the piston 50.

  The cylinder 49 is supported by the apparatus main body 8, and the rotating plate 52 is attached to a support shaft 54 that is rotatably supported by the apparatus main body 8. As shown in FIG. 4, a timing pulley 70 is attached to the support shaft 54, and the timing pulley 70 is fixed to an output shaft of a piston drive motor 71 as a drive motor that is a stepping motor attached to the apparatus body 8. It is drivingly connected by a pinion 72 and a timing belt 73. A dog 55 is attached to the periphery of the rotating plate 52, and this dog 55 is detected by a rotating plate position detection sensor 56 as a rotating plate position detecting means attached to the apparatus main body 8. The arrangement positions of the dog 55 and the rotating plate position detection sensor 56 will be described later.

  With the above-described configuration, the rotational force of the piston drive motor 71 is transmitted to the support shaft 54 via the pinion 72, the timing belt 73, and the timing pulley 70, and the rotational force of the support shaft 54 is transferred to the piston via the rotary plate 52 and the link 53. By being transmitted to 50, the piston 50 is reciprocated in the cylinder 49. The rotary plate 52, the link 53, the support shaft 54, the timing pulley 70, the piston drive motor 71, the pinion 72, and the timing belt 73 constitute a piston drive means 57.

  Here, the arrangement positions of the dog 55 and the rotating plate position detection sensor 56 will be described. As described above, the air supply means 48 is transmitted with the driving force from the piston drive motor 71 and ejects air from the opening 47c. In this stencil printing apparatus 1, the timing of ejecting air from the opening 47c is on the plate cylinder 9. When the paper P fed from the paper feeding unit 4 is pressed by the press roller 11 against the wound master plate 26, the paper P is peeled off from the plate cylinder 9 by the peeling member 47. When the front end of the sheet occupies a position corresponding to the opening 47c, and the sheet P is a large size (in this embodiment, the length in the sheet transport direction is equal to or larger than the A4 side (when the width direction of the sheet is the sheet transport direction)) This is determined when approximately the middle of the length of the paper P in the paper conveyance direction occupies a position corresponding to the opening 47c when the paper is used.

  Accordingly, the piston drive motor 71 is a position where the piston 50 has moved slightly to the right after being positioned on the leftmost side in FIG. 3 in the cylinder 49 when the leading end of the paper P occupies the position corresponding to the opening 47c. 3, the position indicated by a two-dot chain line (when the piston 50 is located on the leftmost side in the cylinder 49, the air ejection pressure from the opening 47 c becomes maximum, but air is supplied to the peeling member 47 through the air hose 51. The rotary plate 52 is actuated to rotate so as to occupy a slight deviation in timing. The rotary plate position detection sensor 56 and the dog 55 are respectively arranged so that the rotary plate position detection sensor 56 becomes a position for detecting the dog 55 when the piston 50 occupies the position indicated by a two-dot chain line in FIG. Yes.

  The piston drive motor 71 also allows the piston 50 to move when a large-size sheet is used as the sheet P and the middle of the sheet conveyance direction length of the sheet P occupies a position corresponding to the opening 47c. 3, the rotary plate 52 is driven to rotate so as to occupy the position indicated by the two-dot chain line. Therefore, when a large-size sheet is used as the sheet P, the piston drive motor 71 rotates the rotating plate 52 twice while the plate cylinder 9 rotates once to reciprocate the piston 50 in the cylinder 49 twice. .

  FIG. 5 shows a block diagram of the control means used in the stencil printing apparatus 1. In the figure, the control means 74 is constituted by a known microcomputer having a CPU, ROM, RAM, etc. therein, and is provided inside the apparatus main body 8. The control means 74 includes various signals from an operation panel 75 provided on the upper front surface of the apparatus main body 8, a paper size detection sensor 34 provided on the apparatus main body 8, a rotating plate position detection sensor 56, a home position sensor 61, and pulse detection. Based on signals from various sensors such as the sensor 69 and operation programs stored in advance, the printing unit 2, plate making unit 3, paper feeding unit 4, plate discharging unit 5, paper discharge unit 6, image reading unit 7, air The operations of the supply means 48 and the like are controlled to control the overall operation of the stencil printing apparatus 1.

  Based on the above-described configuration, the operation of the stencil printing apparatus 1 in the first embodiment will be described below. First, a case will be described in which a small-size sheet (a length in the sheet conveyance direction less than A4 width) is used as the sheet P.

  The operator loads the paper P to be used for printing on the paper feed tray 29, opens the pressure plate 42 and places a document to be printed on the contact glass 41, and then closes the pressure plate 42 again. After that, after setting the plate making conditions with various keys on the operation panel 75, the plate making start key is pressed.

  When the plate making start key is pressed, the control means 74 confirms the size of the paper P stacked on the paper feed tray 29 based on the paper size detection signal from the paper size detection sensor 34. Then, when the paper P is a small size paper, an operation program for a small size paper is read, and when the paper P is a large size paper, an operation program for a large size paper is read. In this case, since the small-size paper P is used, an operation program for small-size paper is read in which the ejection of air from the peeling member 47 to the paper P is performed only at a position corresponding to the front end of the paper.

  When the plate making start key is pressed, the image reading unit 7 performs a document image reading operation. The original image read by the scanning unit 43 is converged by the lens 44, is incident on the image sensor 45, is photoelectrically converted, and is then input to an A / D converter (not shown).

  In parallel with the image reading operation in the image reading unit 7, the plate discharging unit 5 performs a plate discharging operation for peeling the used master 26 from the outer peripheral surface of the plate cylinder 9. When the plate making start key is pressed, the plate cylinder 9 starts to rotate. When the plate cylinder 9 reaches the home position with the clamper 15 positioned directly below, the dog 60 is detected by the home position sensor 61 and controlled by the home position sensor 61. A home position signal is sent to the means 74. Upon receipt of the home position signal, the control means 74 uses the home position as a base point and the tip of the used master 26 wound around the outer peripheral surface of the plate cylinder 9 is the lower discharge plate based on the signal from the pulse detection sensor 69. When it is determined that the predetermined plate discharging position corresponding to the member 36 has been reached, the operation of the plate cylinder driving motor 65 is stopped.

  When the plate cylinder driving motor 65 is stopped and the plate cylinder 9 stops at a predetermined plate discharging position, the lower plate discharging member 36 moves to the plate cylinder 9 side, and the used master 26 is peeled from the plate cylinder 9. The used master 26 that has been peeled off is conveyed into the plate discharge box 37 by the plate release members 35 and 36 and compressed by the compression plate 38. When the plate removal operation is completed, the plate cylinder 9 rotates to the plate supply standby position shown in FIG. 1 and stops, the clamper 15 is opened, and the stencil printing apparatus 1 enters the plate supply standby state.

  When the plate removal operation is completed, the plate making unit 3 performs the plate making operation. When the plate making start key is pressed, the platen roller 21 and each of the master transport roller pairs 24 and 25 are driven to rotate, and the master 26 is pulled out from the master roll 27. When the image forming area of the master 26 reaches a position corresponding to the heat generating element of the thermal head 22, each heat generation of the thermal head 22 is performed based on an image data signal sent from the image sensor 45 via an A / D converter (not shown). The element selectively generates heat, and a plate-making image is formed on the master 26.

  When the leading end of the master-making master 26 is transported to a position where it can be clamped by the clamper 15, the clamper 15 is closed and the master-making master 26 is held on the outer peripheral surface of the plate cylinder 9. Thereafter, the plate cylinder 9 is intermittently rotated clockwise in FIG. 1, and the pre-made master 26 is wound around the plate cylinder 9. When the image data signal is interrupted, the operation of the thermal head 22 is stopped, and when it is determined that the master 26 for one plate has been made by the number of steps of the stepping motor 28, the platen roller 21 and each of the master transport roller pairs 24, 25 Are stopped and the master cutting means 23 is operated to cut the master 26. The cut master 26 is pulled out from the plate making unit 3 by the rotation of the plate cylinder 9, and the plate cylinder 9 rotates to the home position and stops, whereby the plate making operation and the plate feeding operation are completed.

  The printing operation is performed following the plate feeding operation. When the plate cylinder 9 stops at the home position, the paper feed roller 30, the separation roller 31, and the paper discharge conveying member 39 are driven, and the plate cylinder 9 is driven to rotate in the clockwise direction in FIG. The topmost sheet P stacked on the sheet 29 is pulled out and the leading end thereof is held between the registration roller pair 33. Then, the registration roller pair 33 is rotationally driven and pulled out at a predetermined timing when the front end of the plate making image area in the plate cylinder rotation direction of the master 26 wound on the plate cylinder 9 reaches a position corresponding to the press roller 11. The sheet P is fed toward the space between the plate cylinder 9 and the press roller 11.

  The fed paper P is pressed against the master 26 wound around the outer peripheral surface of the plate cylinder 9 by the press roller 11. As a result, the ink supplied to the inner peripheral surface of the plate cylinder 9 by the ink roller 16 oozes out from the opening of the plate cylinder 9 and fills the porous support plate 9a, the mesh screen (not shown), and the porous support body of the master 26. After that, it is transferred to the paper P through the punching portion of the master 26, and so-called printing is performed.

  The sheet P on which the printing image corresponding to the plate-making image is formed by printing is peeled off from the master 26 on the outer peripheral surface of the plate cylinder by the peeling member 47 from the leading end. At the time of peeling, the piston drive motor 71 is operated, and the piston 50 reciprocates once in the cylinder 49, whereby air is ejected from the opening 47c, and the paper P is peeled off from the outer peripheral surface of the plate cylinder.

  The operation of the piston drive motor 71 is based on the plate cylinder angle signal from the pulse detection sensor 69, and the rotary plate position detection sensor 56 detects the dog 55 when the leading end of the paper P reaches the position corresponding to the opening 47c. It is controlled by the control means 74 so that it is time to perform. By the control of the control means 74, air is ejected from the opening 47c between the leading end portion of the paper P and the master 26 on the outer peripheral surface of the plate cylinder. The peeled paper P falls downward and is received by the paper discharge conveyance member 39, and is then conveyed and discharged onto the paper discharge tray 40. Thereafter, the plate cylinder 9 rotates again to the home position and stops, and the stencil printing apparatus 1 enters a printing standby state after finishing the plate attaching operation.

  After the stencil printing apparatus 1 enters the print standby state, when a test printing key is pressed after inputting printing conditions using various keys on the operation panel 75, trial printing is performed. When the trial printing key is pressed, the plate cylinder 9 is driven to rotate at a peripheral speed corresponding to the set printing speed, and one sheet P is fed from the paper feeding unit 4. The fed paper P is temporarily stopped by the registration roller pair 33 and then fed toward the printing unit 2 at the same timing as that for printing, and is pressed against the master 26 on the outer peripheral surface of the plate cylinder by the press roller 11. . The paper P on which the printed image is formed is peeled off from the master 26 on the outer peripheral surface of the plate cylinder by the peeling member 47, sent to the paper discharge unit 6, transported by the paper discharge transport member 39, and discharged onto the paper discharge tray 40. Is done. Even during the trial printing, when the paper P is peeled from the outer peripheral surface of the plate cylinder, air is sent from the air supply means 48 in the same manner as described above, and the paper P is peeled well.

  When the print start key is pressed after setting the number of prints after confirming the image position or image density by trial printing, the paper P is continuously fed from the paper supply unit 4 and printing operation is performed in the same way as during trial printing. Is done. When the set number of prints is consumed, the plate cylinder 9 stops at the home position, and the stencil printing apparatus 1 enters the print standby state again. Even during this printing operation, when the paper P is peeled from the outer peripheral surface of the plate cylinder, air is sent from the air supply means 48 as described above, and the paper P is peeled well.

  Next, a case where a large size paper is used as the paper P will be described. When the plate making start key is pressed by the operator, the control means 74 confirms the size of the paper P loaded on the paper feed tray 29 based on a signal from the paper size detection sensor 34, and operates for large size paper. Load the program. In this case, the ejection of air from the peeling member 47 to the paper P is performed at a position corresponding to the front end of the paper and a position corresponding to approximately the middle of the length in the paper transport direction.

  When the plate making start key is pressed, the image reading operation and the plate discharging operation are performed as described above, and the plate making operation and the plate feeding operation are performed after the stencil printing apparatus 1 enters the plate feeding standby state. When the plate feeding operation is completed, one sheet P is pulled out from the sheet feeding tray 29, and the sheet P is temporarily stopped by the registration roller pair 33 and then fed toward the printing unit 2.

  The fed paper P is pressed by the master 26 wound around the outer peripheral surface of the plate cylinder 9 rotating at a low speed by the press roller 11, and printing is performed. The sheet P on which the printing image corresponding to the plate-making image is formed by printing is peeled off from the master 26 on the outer peripheral surface of the plate cylinder by the peeling member 47 from the front end portion thereof. At the time of peeling, the piston drive motor 71 operates and the piston 50 reciprocates twice within the cylinder 49, whereby air is jetted twice from the opening 47c, and the paper P is peeled off from the outer peripheral surface of the plate cylinder.

  The operation of the piston drive motor 71 is performed when the leading end portion of the paper P reaches the position corresponding to the opening 47c and the center of the length of the paper P in the paper conveyance direction with reference to the plate cylinder angle signal from the pulse detection sensor 69. The control means 74 controls the rotating plate position detection sensor 56 to detect the dog 55 when the part reaches the position corresponding to the opening 47c. By the control of the control means 74, between the leading end of the paper P and the master 26 on the outer peripheral surface of the plate cylinder, and between the substantially central portion of the length of the paper P in the paper transport direction and the master 26 on the outer peripheral surface of the plate cylinder. Air is ejected from the opening 47c toward the end. The peeled paper P falls downward and is received by the paper discharge conveyance member 39, and is then conveyed and discharged onto the paper discharge tray 40. Thereafter, the plate cylinder 9 rotates again to the home position and stops, and the stencil printing apparatus 1 enters a printing standby state after finishing the plate attaching operation.

  When the trial printing key on the operation panel 75 is pressed after the stencil printing apparatus 1 is in a print standby state, the plate cylinder 9 is driven to rotate at a peripheral speed corresponding to the set printing speed and the paper feeding unit 4 From the sheet feeding section 4, the plate cylinder 9 is rotated and driven at a peripheral speed corresponding to the set printing speed when a test printing is performed by feeding only one sheet P from the printing start key. The paper P is continuously fed and a printing operation is performed. Even during the trial printing and printing operation, when the paper P is peeled from the outer peripheral surface of the plate cylinder, air is sent twice from the air supply means 48 in the same manner as the plate attachment, so that the paper P is peeled well. Is called.

  According to the configuration described above, the position corresponding to the leading end of the paper when printing using small size paper, and the central portion of the leading end of the paper and the conveyance direction of the paper when printing using large size paper are provided. Since air is ejected from the opening 47c of the peeling member 47 at a position corresponding to the above, even if the paper P has a solid image portion that extends substantially rearward from the entire surface or the central portion in the paper conveyance direction. The paper P adhered to the master 26 on the outer peripheral surface of the plate cylinder can be peeled off satisfactorily due to the adhesive force of the ink. Therefore, it is possible to obtain a good printed matter by preventing the occurrence of the problem of causing the problem.

  In this embodiment, the piston 50 makes one reciprocation in the cylinder 49 during one rotation of the plate cylinder 9 when using small size paper, and the piston 50 makes two reciprocations in the cylinder 49 during one rotation of the plate cylinder 9 when using large size paper. The structure to be adopted is adopted. Here, since the rotational peripheral speed of the plate cylinder 9 can be changed according to the printing speed, the time during which the plate cylinder 9 makes one rotation also changes according to the printing speed. For this reason, in this embodiment, the reciprocating speed of the piston 50 is intermittent with the rotational peripheral speed of the piston drive motor 71 as a constant speed so as to be a constant speed that is twice or more the maximum rotational peripheral speed of the plate cylinder 9. The control is performed so as to be rotationally driven.

  Note that the rotational peripheral speed of the piston drive motor 71 may be changed in accordance with the rotational peripheral speed of the plate cylinder 9, but in this case, when the plate cylinder 9 is rotated at a low speed, such as during the printing operation, the piston The moving speed of 50 is also decelerated, and the air ejection pressure from the opening 47c is reduced, and good peeling may not be performed. In such a case, it is necessary to increase the rotational peripheral speed of the piston drive motor 71 as appropriate so as to keep the air ejection pressure from the opening 47c above a certain value.

  FIG. 6 shows air supply means used in the second embodiment of the present invention. The air supply means 76 includes a first cylinder 77, a first piston 78 that can reciprocate inside the first cylinder 77, one end connected to the air discharge port 77 a of the first cylinder 77, and the other end connected to one end of the peeling member 47. An air hose 80 connected to a Y-shaped joint 79 attached to the first rotary plate 81, a first link 82 having one end attached to the periphery of the first rotary plate 81 and the other end attached to the first piston 78, 2 cylinder 83, a second piston 84 capable of reciprocating inside the second cylinder 83, an air hose 85 having one end connected to the air discharge port 83a of the second cylinder 83 and the other end connected to a Y-shaped joint 79, a second The rotary plate 86 mainly includes a second link 87 having one end attached to the periphery of the second rotary plate 86 and the other end attached to the second piston 84.

  The cylinders 77 and 83 are respectively supported by the apparatus main body 8, the first rotary plate 81 is rotatably supported by the support body 88, and the second rotary plate 86 is freely rotatable by the apparatus main body 8. Each is attached to a supported spindle 89. As shown in FIG. 7, a timing pulley 90 is attached to the support shaft 88, and a timing pulley 91 is attached to the support shaft 89. The timing pulley 90 is a first piston drive motor 92 as a drive motor that is a stepping motor. The timing pulley 91 is driven and connected by a pinion 96 fixed to the output shaft of the second piston drive motor 95 as a stepping motor and a timing belt 97, respectively. Has been.

  A dog 98 is attached to the peripheral edge of the first rotary plate 81, and a dog 99 is attached to the peripheral edge of the second rotary plate 86. The dogs 98 and 99 each detect the first rotary plate position as rotary plate position detecting means. It is detected by the sensor 100 and the second rotary plate position detection sensor 101, respectively. The arrangement positions of the dogs 98 and 99 and the rotary plate position detection sensors 100 and 101 are the same as the positional relationship between the dog 55 and the rotary plate position detection sensor 56 in the first embodiment.

  The first piston plate 102, the first link 82, the support shaft 88, the timing pulley 90, the first piston drive motor 92, the pinion 93, and the timing belt 94 make the first piston drive means 102, the second rotary plate 86, The second piston 87 is constituted by the second link 87, the support shaft 89, the timing pulley 91, the second piston drive motor 95, the pinion 96, and the timing belt 97.

Based on the above-described configuration, the operation of the stencil printing apparatus 1 in the second embodiment will be described below. First, a case where a small size paper is used as the paper P will be described.
When the plate making start key is pressed by the operator, the control means 74 confirms the size of the paper P loaded on the paper feed tray 29 based on the signal from the paper size detection sensor 34, and operates for small size paper. Load the program. In this case, air is ejected from the peeling member 47 to the paper P only at a position corresponding to the front end of the paper.

  When the plate making start key is pressed, the image reading operation and the plate discharging operation are performed as in the first embodiment, and the plate making operation and the plate feeding operation are performed after the stencil printing apparatus 1 enters the plate feeding standby state. When the plate feeding operation is completed, one sheet P is pulled out from the sheet feeding tray 29, and the sheet P is temporarily stopped by the registration roller pair 33 and then fed toward the printing unit 2.

  The fed paper P is pressed by the master 26 wound around the outer peripheral surface of the plate cylinder 9 rotating at a low speed by the press roller 11, and printing is performed. The paper P on which the print image is formed is peeled off from the master 26 on the outer peripheral surface of the plate cylinder by the peeling member 47 from the front end portion thereof. At the time of separation, either the first piston drive motor 92 or the second piston drive motor 95 is operated, and either the first piston 78 or the second piston 84 reciprocates in the corresponding cylinder to open the opening. The air is ejected from 47c, and the paper P is peeled favorably from the outer peripheral surface of the plate cylinder.

  The operations of the first piston drive motor 92 and the second piston drive motor 95 are performed when the leading end of the paper P reaches the position corresponding to the opening 47c with reference to the plate cylinder angle signal from the pulse detection sensor 69. The rotation plate position detection sensor 100 is controlled by the control means 74 so that the dog 98 is detected, and the second rotation plate position detection sensor 101 is detected at the timing when the dog 99 is detected. By the control of the control means 74, air is ejected from the opening 47c between the leading end portion of the paper P and the master 26 on the outer peripheral surface of the plate cylinder. The peeled paper P falls downward and is received by the paper discharge conveyance member 39, and is then conveyed and discharged onto the paper discharge tray 40. Thereafter, the plate cylinder 9 rotates again to the home position and stops, and the stencil printing apparatus 1 enters a printing standby state after finishing the plate attaching operation.

  When the trial printing key on the operation panel 75 is pressed after the stencil printing apparatus 1 is in a print standby state, the plate cylinder 9 is driven to rotate at a peripheral speed corresponding to the set printing speed and the paper feeding unit 4 From the sheet feeding section 4, the plate cylinder 9 is rotated and driven at a peripheral speed corresponding to the set printing speed when a test printing is performed by feeding only one sheet P from the printing start key. The paper P is continuously fed and a printing operation is performed. Even during the trial printing and the printing operation, air is sent from the air supply means 76 when the paper P is peeled off from the outer peripheral surface of the plate cylinder, and the paper P is peeled off satisfactorily.

  Next, a case where a large size paper is used as the paper P will be described. When the plate making start key is pressed by the operator, the control means 74 confirms the size of the paper P loaded on the paper feed tray 29 based on a signal from the paper size detection sensor 34, and operates for large size paper. Load the program. In this case, the ejection of air from the peeling member 47 to the paper P is performed at a position corresponding to the front end of the paper and a position corresponding to approximately the middle of the length in the paper transport direction.

  When the plate making start key is pressed, the image reading operation and the plate discharging operation are performed as described above, and the plate making operation and the plate feeding operation are performed after the stencil printing apparatus 1 enters the plate feeding standby state. When the plate feeding operation is completed, one sheet P is pulled out from the sheet feeding tray 29, and the pulled-out sheet P is temporarily stopped by the registration roller pair 33 and then fed toward the printing unit 2.

  The fed paper P is pressed by the master 26 wound around the outer peripheral surface of the plate cylinder 9 rotating at a low speed by the press roller 11, and printing is performed. The paper P on which the print image is formed is peeled off from the master 26 on the outer peripheral surface of the plate cylinder by the peeling member 47 from the front end portion thereof. At the time of separation, the first piston drive motor 92 and the second piston drive motor 95 are operated, and the first piston 78 and the second piston 84 reciprocate in the corresponding cylinders, so that air is supplied twice from the opening 47c. The ejection of the paper P from the outer peripheral surface of the plate cylinder is performed well.

  The operations of the first piston drive motor 92 and the second piston drive motor 95 are performed when the leading end of the paper P reaches the position corresponding to the opening 47c with reference to the plate cylinder angle signal from the pulse detection sensor 69. The second rotation plate position detection sensor is set so that the rotation plate position detection sensor 100 detects the dog 98 and when the substantially central portion of the length of the sheet P in the sheet conveyance direction reaches a position corresponding to the opening 47c. The control means 74 controls each of the timings 101 to detect the dog 99. By the control of the control means 74, between the leading end of the paper P and the master 26 on the outer peripheral surface of the plate cylinder, and between the substantially central portion of the length of the paper P in the paper transport direction and the master 26 on the outer peripheral surface of the plate cylinder. Air is ejected from the opening 47c toward the end. The peeled paper P falls downward and is received by the paper discharge conveyance member 39, and is then conveyed and discharged onto the paper discharge tray 40. Thereafter, the plate cylinder 9 rotates again to the home position and stops, and the stencil printing apparatus 1 enters a printing standby state after finishing the plate attaching operation.

  When the trial printing key on the operation panel 75 is pressed after the stencil printing apparatus 1 is in a print standby state, the plate cylinder 9 is driven to rotate at a peripheral speed corresponding to the set printing speed and the paper feeding unit 4 From the sheet feeding section 4, the plate cylinder 9 is rotated and driven at a peripheral speed corresponding to the set printing speed when a test printing is performed by feeding only one sheet P from the printing start key. The paper P is continuously fed and a printing operation is performed. Even during the trial printing and printing operation, when the paper P is peeled from the outer peripheral surface of the plate cylinder, air is sent twice from the air supply means 76 in the same manner as the printing, so that the paper P is peeled well. Is called.

  In the above embodiment, the length of the sheet P in the sheet conveyance direction is set so that the second rotation plate position detection sensor 101 detects the dog 99 when the leading end of the sheet P reaches the position corresponding to the opening 47c. The control means 74 controls the piston drive motors 92 and 95 so that the first rotary plate position detection sensor 100 detects the dog 98 when the substantially central portion reaches the position corresponding to the opening 47c. It is good also as composition to do.

  Also in the present embodiment, as in the first embodiment, at the time of printing using a small size paper, at the position corresponding to the paper front end, and at the time of printing using a large size paper, the paper front end and the conveyance of the paper Since air is ejected from the opening 47c of the peeling member 47 at a position corresponding to the approximately central portion in the direction length, the same effect as that of the first embodiment can be obtained.

  In this embodiment, when a small size paper is used, one of the pistons 78 and 84 is reciprocated once in one rotation of the plate cylinder 9 during one rotation of the plate cylinder 9, and when a large size paper is used, the plate cylinder 9 is rotated. A configuration is adopted in which each piston 78, 84 reciprocates once within the corresponding cylinder 77, 83 during one rotation. Also in this embodiment, since the rotational peripheral speed of the plate cylinder 9 can be changed according to the printing speed, the time during which the plate cylinder 9 makes one rotation also changes according to the printing speed. For this reason, in this embodiment, the rotational peripheral speeds of the piston drive motors 92 and 95 are constant speeds so that the reciprocating speeds of the pistons 78 and 84 are constant speeds that are equal to or higher than the maximum rotational peripheral speed of the plate cylinder 9. As shown in FIG.

  The rotational peripheral speed of each of the piston drive motors 92 and 95 may be changed in accordance with the rotational peripheral speed of the plate cylinder 9, but in this case, the plate cylinder 9 is rotated at a low speed such as during the plate-making operation. , The moving speeds of the pistons 78 and 84 are also decelerated, and the air ejection pressure from the opening 47c may be reduced, preventing good separation. In such a case, it is necessary to increase the rotational peripheral speed of the piston drive motors 92 and 95 as appropriate so as to keep the air ejection pressure from the opening 47c above a certain value.

  In each of the first and second embodiments described above, the piston 50 is reciprocated by the piston drive motor 71, the first piston 78 is moved by the first piston drive motor 92, and the second piston 84 is moved by the second piston drive motor 95. However, the piston driving motors 71, 92, and 95 are not used, and the rotational driving force from the plate cylinder driving means 58 is transmitted by driving force transmission means such as a gear or a belt, and the pistons 50, 78, and 84 are transmitted. It is good also as a structure which reciprocates.

  When this configuration is adopted in the first embodiment, it is necessary to reciprocate the piston 50 once during the rotation of the plate cylinder when using small size paper, and to reciprocate the piston 50 twice during the rotation of the plate cylinder when using large size. Therefore, there are two driving force transmission means: a path for transmitting the rotational driving force for one rotation of the plate cylinder as a driving force for one reciprocation of the piston and a path for transmitting the driving force while increasing the driving force for two pistons. It is necessary to configure one path and switch the driving force transmission path by the switching means.

  In both the first and second embodiments, when large-size paper is used, it is necessary to eject air at a position approximately in the middle of the paper P conveyance direction. It is necessary to change the spout location. In this case, it is necessary to control the reciprocating motion of each piston 50, 78, 84 by using a disconnecting means such as a clutch for connecting or disconnecting the driving force as the driving force transmitting means.

  FIG. 8 shows a schematic front view of a stencil printing apparatus 104 employing the third embodiment of the present invention. The stencil printing device 104 is different from the stencil printing device 1 shown in the first embodiment in that it does not have the paper size detection sensor 34, has the image memory 105, and is replaced with the control means 74. The difference is only in that the control means 106 is provided, and the other configurations are the same, and the air supply means 48 is provided.

  The image memory 105 is provided in the image reading unit 7 and stores an image data signal for one document sent from an A / D converter (not shown). The stored image data signal is sent to a thermal head driver (not shown) that drives the thermal head 22 line by line during plate making operation, and each heating element of the thermal head 22 is selectively selected based on the image data signal. The master plate 26 is operated to perform the plate making.

  FIG. 9 shows a block diagram of control means used in the stencil printing apparatus 104. The control means 106 is constituted by a microcomputer similar to the control means 74 and is provided inside the apparatus main body 8.

  The control means 106 stores various signals from the operation panel 75, signals from various sensors such as the rotary plate position detection sensor 56, home position sensor 61, and pulse detection sensor 69 provided in the apparatus body 8, and stored in advance. Based on the operation program, the operations of the printing unit 2, the plate making unit 3, the paper feeding unit 4, the plate discharging unit 5, the paper discharging unit 6, the image reading unit 7, the air supply unit 48, etc. are controlled, respectively. To control the operation.

  Further, the control means 106 determines whether or not the original has a solid image portion from the image data signal stored in the image memory 105 and to which portion the solid image portion exists using a predetermined threshold value. When there is a solid image portion, it has a function of detecting its position.

  In this stencil printing apparatus 104, the air is ejected from the opening 47c at a timing when the paper P fed from the paper feeding unit 4 is pressed by the press roller 11 against the master 26 that has been wound around the plate cylinder 9. When the leading end of the paper P occupies a position corresponding to the opening 47c when being peeled from the plate cylinder 9 by the peeling member 47, and when there is a solid image portion on the master 26 that has been made In addition, it is determined when the solid image portion printed on the paper P occupies a position corresponding to the opening 47c.

  Therefore, the piston drive motor 71 rotates the rotating plate 52 once during the rotation of the plate cylinder 9 and makes the piston 50 reciprocate once in the cylinder 49 when there is no solid image portion on the master 26 that has been made. When a solid image portion is present in the master 26 that has been subjected to plate making, the rotating plate 52 is rotated twice while the plate cylinder 9 rotates once, and the piston 50 is reciprocated twice within the cylinder 49. If it is determined by detection of the presence or absence of a solid image portion that there are two or more solid image portions in the master 26 that has been subjected to plate making, the ejection of air from the opening 47c should be located on the most downstream side in the sheet conveying direction. It is performed only for the image part.

  Based on the above configuration, the operation of the stencil printing apparatus 104 will be described below. The operator opens the pressure plate 42 and places a document to be printed on the contact glass 41, and then closes the pressure plate 42 again. After that, after setting the plate making conditions with various keys on the operation panel 75, the plate making start key is pressed. When the plate making start key is pressed, the image reading unit 7 performs a document image reading operation. The original image read by the scanning unit 43 is converged by the lens 44, is incident on the image sensor 45, is photoelectrically converted, passes through an A / D converter (not shown), and is converted into an image data signal for one original. Stored in the memory 105.

  When the image data signal for one document is stored in the image memory 105, the control means 106 determines whether or not a solid image portion exists in the document image. If it is determined at this time that there is no solid image portion in the original image, an operation program for solid image portion is read in which the ejection of air from the peeling member 47 to the paper P is performed only at a position corresponding to the front end portion of the paper. If it is determined that the original image has a solid image portion, an operation for the presence of a solid image portion is performed at a position corresponding to the leading edge portion of the paper and a position corresponding to the solid image portion from the peeling member 47. The program is loaded. The operation of the stencil printing apparatus 104 when there is no solid image portion is the same as the operation of the stencil printing apparatus 1 when using small-size paper in the first embodiment, and a description thereof will be omitted here. Only the operation of the stencil printing apparatus 104 when there is an image portion will be described.

  In parallel with the image reading operation in the image reading unit 7, the plate discharging unit 5 performs the plate discharging operation as in the first embodiment, and the plate feeding operation is performed after the plate discharging operation is completed. When the plate feeding operation is completed, one sheet P is pulled out from the sheet feeding tray 29, and the sheet P is temporarily stored in the registration roller pair 33 and then fed toward the printing unit 2.

  The fed paper P is pressed by the master 26 wound around the outer peripheral surface of the plate cylinder 9 rotating at a low speed by the press roller 11, and printing is performed. The paper P on which the print image is formed is peeled off from the master 26 on the outer peripheral surface of the plate cylinder by the peeling member 47 from the front end thereof. At the time of peeling, the piston drive motor 71 operates and the piston 50 reciprocates twice within the cylinder 49, whereby air is jetted twice from the opening 47c, and the paper P is peeled off from the outer peripheral surface of the plate cylinder.

  The operation of the piston drive motor 71 is based on the plate cylinder angle signal from the pulse detection sensor 69 when the leading edge of the paper P reaches a position corresponding to the opening 47c and the solid image portion is positioned to correspond to the opening 47c. Control unit 106 controls the rotation plate position detection sensor 56 to detect the dog 55 when it reaches. Under the control of the control means 106, it is directed between the leading end of the paper P and the master 26 on the outer periphery of the plate cylinder and between the position corresponding to the solid image portion of the paper P and the master 26 on the outer periphery of the plate cylinder. Thus, air is ejected from the opening 47c. The peeled paper P falls downward and is received by the paper discharge conveyance member 39, and is then conveyed and discharged onto the paper discharge tray 40. Thereafter, the plate cylinder 9 rotates again to the home position and stops, and the stencil printing apparatus 104 enters a printing standby state after finishing the plate setting operation.

  When the trial printing key on the operation panel 75 is pressed after the stencil printing apparatus 104 enters the printing standby state, the plate cylinder 9 is driven to rotate at a peripheral speed corresponding to the set printing speed, and the paper feeding unit 4 From the sheet feeding section 4, the plate cylinder 9 is rotated and driven at a peripheral speed corresponding to the set printing speed when a test printing is performed by feeding only one sheet P from the printing start key. The paper P is continuously fed and a printing operation is performed. Even during the trial printing and printing operation, when the paper P is peeled from the outer peripheral surface of the plate cylinder, air is sent twice from the air supply means 48 in the same manner as the plate attachment, so that the paper P is peeled well. Is called.

  According to the configuration described above, the position corresponding to the front end portion of the paper when printing a document having no solid image portion, and the front end portion and the solid image portion corresponding to the paper having a solid image portion are printed. Since air is ejected from the opening 47c of the peeling member 47 at the position, even if the sheet P has a solid image portion extending substantially rearward from the central portion in the sheet conveying direction. The paper P attached to the master 26 on the outer peripheral surface of the plate cylinder can be peeled off satisfactorily by the adhesive force, and the paper P has a defect that causes nail mark stains, or the paper P is stuck in the peeling member 47 and causes a conveyance jam. Therefore, it is possible to obtain a good printed matter by preventing the occurrence of a malfunction.

  In the present embodiment, the piston 50 makes one reciprocation within the cylinder 49 during one rotation of the plate cylinder 9 when printing a document having no solid image portion, and one rotation of the plate cylinder 9 when printing a document having a solid image portion. Since the piston 50 reciprocates twice in the cylinder 49 and the rotational peripheral speed of the plate cylinder 9 can be changed according to the printing speed, the reciprocating speed of the piston 50 is twice the maximum rotational peripheral speed of the plate cylinder 9. Control is performed such that the rotation peripheral speed of the piston drive motor 71 is intermittently driven at a constant speed so that the constant speed is the above speed.

  Note that the rotational peripheral speed of the piston drive motor 71 may be changed in accordance with the rotational peripheral speed of the plate cylinder 9, but in this case, when the plate cylinder 9 is rotated at a low speed, such as during the printing operation, the piston The moving speed of the motor 50 is also reduced, and the air ejection pressure from the opening 47c may be reduced to prevent good separation. In such a case, the rotational peripheral speed of the piston drive motor 71 is appropriately increased, It is necessary to make it the structure which keeps the ejection pressure of the air from the opening 47c more than a fixed value.

  Next, a fourth embodiment of the present invention will be described. The fourth embodiment differs from the third embodiment described above only in that the air supply means 76 shown in the second embodiment is used instead of the air supply means 48, and the other embodiments are different. The configuration is the same. The operation of the stencil printing apparatus 104 in the fourth embodiment will be described below.

  When the plate making start key is pressed by the operator, a document image reading operation is performed in the image reading unit 7, and the read document image is stored in the image memory 105 as an image data signal. Next, it is determined by the control means 106 whether or not a solid image portion exists in the original image, and an operation program for the absence of a solid image portion or an operation program for the presence of a solid image portion is read. Since the operation of the stencil printing apparatus 104 without a solid image portion is the same as the operation of the stencil printing apparatus 1 when using small-size paper in the second embodiment, the description thereof is omitted here. Only the operation of the stencil printing apparatus 104 when there is an image portion will be described.

  In parallel with the image reading operation in the image reading unit 7, the plate discharging unit 5 performs the plate discharging operation as in the second embodiment, and the plate feeding operation is performed after the plate discharging operation is completed. When the plate feeding operation is completed, one sheet P is pulled out from the sheet feeding tray 29, and the sheet P is temporarily stopped by the registration roller pair 33 and then fed toward the printing unit 2.

  The fed paper P is pressed by the master 26 wound around the outer peripheral surface of the plate cylinder 9 rotating at a low speed by the press roller 11, and printing is performed. The paper P on which the print image is formed is peeled off from the master 26 on the outer peripheral surface of the plate cylinder by the peeling member 47 from the front end thereof. At the time of separation, the first piston drive motor 92 and the second piston drive motor 95 are operated, and the first piston 78 and the second piston 84 reciprocate in the corresponding cylinders, so that air is supplied twice from the opening 47c. The ejection of the paper P from the outer peripheral surface of the plate cylinder is performed well.

  The operations of the first piston drive motor 92 and the second piston drive motor 95 are performed when the leading end of the paper P reaches the position corresponding to the opening 47c with reference to the plate cylinder angle signal from the pulse detection sensor 69. The timing at which the second rotating plate position detection sensor 101 detects the dog 99 when the solid image portion reaches a position corresponding to the opening 47c, so that the timing at which the rotating plate position detection sensor 100 detects the dog 98 is reached. It is controlled by the control means 106 respectively. Under the control of the control means 106, it is directed between the leading end of the paper P and the master 26 on the outer periphery of the plate cylinder and between the position corresponding to the solid image portion of the paper P and the master 26 on the outer periphery of the plate cylinder. Thus, air is ejected from the opening 47c. The peeled paper P falls downward and is received by the paper discharge conveyance member 39, and is then conveyed and discharged onto the paper discharge tray 40. Thereafter, the plate cylinder 9 rotates again to the home position and stops, and the stencil printing apparatus 104 enters a printing standby state after finishing the plate setting operation.

  When the trial printing key on the operation panel 75 is pressed after the stencil printing apparatus 104 enters the printing standby state, the plate cylinder 9 is driven to rotate at a peripheral speed corresponding to the set printing speed, and the paper feeding unit 4 From the sheet feeding section 4, the plate cylinder 9 is rotated and driven at a peripheral speed corresponding to the set printing speed when a test printing is performed by feeding only one sheet P from the printing start key. The paper P is continuously fed and a printing operation is performed. Even during the trial printing and printing operation, when the paper P is peeled from the outer peripheral surface of the plate cylinder, air is sent twice from the air supply means 76 in the same manner as the printing, so that the paper P is peeled well. Is called.

  In the above-described embodiment, the solid image portion has the opening 47c so that the second rotating plate position detection sensor 101 detects the dog 99 when the leading end of the paper P reaches the position corresponding to the opening 47c. The control means 106 may control the piston drive motors 92 and 95 so that the first rotary plate position detection sensor 100 detects the dog 98 when the corresponding position is reached.

  Also in the present embodiment, as in the third embodiment, when printing a document that does not have a solid image portion, at the position corresponding to the leading edge portion of the paper, and at the time of printing a document having a solid image portion, In addition, since air is ejected from the opening 47c of the peeling member 47 at a position corresponding to the solid image portion, the same effect as that of the third embodiment can be obtained.

  In the present embodiment, during printing of a document that does not have a solid image portion, during one rotation of the plate cylinder 9, one of the pistons 78 and 84 is reciprocated once in the corresponding cylinder 77 and 83, and a solid image. When printing a document having a portion, the pistons 78 and 84 reciprocate once in the corresponding cylinders 77 and 83 during one rotation of the plate cylinder 9, and the rotational peripheral speed of the plate cylinder 9 can be changed according to the printing speed. Therefore, the reciprocating speeds of the pistons 78 and 84 are intermittent with the rotational peripheral speeds of the piston drive motors 92 and 95 being constant so that the reciprocating speed of the pistons 78 and 84 is equal to or higher than the maximum rotational peripheral speed of the plate cylinder 9. The control is performed so as to be rotationally driven.

  The rotational peripheral speed of each of the piston drive motors 92 and 95 may be changed in accordance with the rotational peripheral speed of the plate cylinder 9, but in this case, the plate cylinder 9 is rotated at a low speed such as during the plate-making operation. In this case, the moving speed of the pistons 78 and 84 is also reduced, and the air ejection pressure from the opening 47c may be reduced to prevent good separation. In this case, the piston drive motors 92 and 95 It is necessary to make it the structure which raises the rotation peripheral speed of this suitably, and maintains the jet pressure of the air from the opening 47c more than a fixed value.

  In each of the third and fourth embodiments described above, the piston 50 is reciprocated by the piston drive motor 71, the first piston 78 is moved by the first piston drive motor 92, and the second piston 84 is moved by the second piston drive motor 95. However, the piston driving motors 71, 92, and 95 are not used, and the rotational driving force from the plate cylinder driving means 58 is transmitted by driving force transmission means such as a gear or a belt, and the pistons 50, 78, and 84 are transmitted. It is good also as a structure which reciprocates.

  When this configuration is adopted in the third embodiment, the piston 50 is reciprocated once during rotation of the plate cylinder when printing a document that does not have a solid image portion, and the plate is printed when a document having a solid image portion is printed. Since it is necessary to reciprocate the piston 50 twice during one rotation of the cylinder, the driving force transmitting means is a path for transmitting a rotational driving force for one rotation of the plate cylinder as a driving force for one reciprocation of the piston and driving for two reciprocations of the piston. It is necessary to configure two paths, a path for transmitting while increasing the speed as a force, and switching the driving force transmission path by the switching means.

  In both the third and fourth embodiments, when printing a document having a solid image portion, it is necessary to eject air at a position corresponding to the solid image portion. Need to be changed. In this case, it is necessary to control the reciprocating motion of each piston 50, 78, 84 by using a disconnecting means such as a clutch for connecting or disconnecting the driving force as the driving force transmitting means.

  FIG. 10 shows a schematic front view of a stencil printing apparatus 107 adopting the fifth embodiment of the present invention. The stencil printing apparatus 107 differs from the stencil printing apparatus 1 shown in the first embodiment only in that it has an image memory 105 and a control means 108 instead of the control means 74. The other configurations are the same, and air supply means 48 is provided.

  FIG. 11 shows a block diagram of control means used in the stencil printing apparatus 107. The control means 108 is constituted by a microcomputer similar to the control means 74 and is provided inside the apparatus main body 8.

  The control means 108 includes various signals from the operation panel 75, signals from various sensors such as a paper size detection sensor 34, a rotating plate position detection sensor 56, a home position sensor 61, and a pulse detection sensor 69 provided in the apparatus body 8. And the operations of the printing unit 2, the plate making unit 3, the paper feeding unit 4, the plate discharging unit 5, the paper discharging unit 6, the image reading unit 7, the air supply unit 48, and the like are controlled based on pre-stored operation programs. The overall operation of the stencil printing apparatus 107 is controlled. Further, the control means 108 determines whether or not the original has a solid image portion from the image data signal stored in the image memory 105, and in which portion the solid image portion exists using a predetermined threshold value. When there is a solid image portion, it has a function of detecting its position.

  In the stencil printing apparatus 107, the air is blown out from the opening 47c when the sheet P fed from the sheet feeding unit 4 is pressed by the press roller 11 against the master 26 that has been wound around the plate cylinder 9 and is pressed. Then, when the leading end of the paper P occupies a position corresponding to the opening 47c when being peeled from the plate cylinder 9 by the peeling member 47, and as the paper P, a large size (in the present embodiment, A4 side ( When the short side direction of the paper is set as the paper conveyance direction), when the paper having the above paper conveyance direction length) is used, the middle of the paper conveyance direction length of the paper P occupies a position corresponding to the opening 47c. And when the solid image portion exists in the master 26 after the plate making, the solid image portion occupies a position corresponding to the opening 47c.

  When a large-size sheet is used as the sheet P and there is a solid image portion on the master 26 that has been made, the timing of ejecting air from the opening 47c corresponds to the leading end of the sheet P corresponding to the opening 47c. It is determined when the position is occupied and when the middle of the length of the sheet P in the sheet conveyance direction occupies a position corresponding to the opening 47c.

  Therefore, the piston drive motor 71 rotates the rotating plate 52 once while the plate cylinder 9 rotates once when a small size sheet is used as the sheet P and there is no solid image portion on the master 26 that has been made. When the piston 50 is reciprocated once in the cylinder 49 and a large-size sheet is used as the sheet P and / or when a solid image portion exists in the master 26 that has been subjected to plate making, the plate cylinder 9 is rotated once. The rotating plate 52 is rotated twice to reciprocate the piston 50 in the cylinder 49 twice. If it is determined by detection of the presence or absence of a solid image portion that there are two or more solid image portions in the master 26 that has been subjected to plate making, the ejection of air from the opening 47c should be located on the most downstream side in the sheet conveying direction. It is performed only for the image part (when using small size paper).

  Based on the above configuration, the operation of the stencil printing apparatus 107 will be described below. The operator opens the pressure plate 42 and places a document to be printed on the contact glass 41, and then closes the pressure plate 42 again. After that, after setting the plate making conditions with various keys on the operation panel 75, the plate making start key is pressed.

  When the plate making start key is pressed, the control means 108 confirms the size of the paper P stacked on the paper feed tray 29 based on the paper size detection signal from the paper size detection sensor 34. First, a case where the paper P is a small size paper will be described.

  When the plate making start key is pressed, the image reading unit 7 performs a document image reading operation. The original image read by the scanning unit 43 is converged by the lens 44, is incident on the image sensor 45, is photoelectrically converted, passes through an A / D converter (not shown), and is converted into an image data signal for one original. Stored in the memory 105.

  When the image data signal for one original is stored in the image memory 105, the control means 108 determines whether or not there is a solid image portion in the original image. If it is determined that there is no solid image portion in the original image at this time, an operation program for no small size solid image portion in which the ejection of air from the peeling member 47 to the paper P is performed only at a position corresponding to the front end portion of the paper. When it is determined that the original image has a solid image portion, a small size paper solid is produced in which air is ejected from the peeling member 47 to the paper P at a position corresponding to the front end of the paper and a position corresponding to the solid image portion. An operation program for the presence of an image portion is read.

  The operation of the stencil printing apparatus 107 when there is no small-size sheet solid image portion is the same as the operation of the stencil printing apparatus 1 when the small-size sheet is used in the first embodiment. The operation of the stencil printing apparatus 107 is the same as that of the stencil printing apparatus 104 with a solid image portion in the third embodiment.

  Next, a case where the paper P is a large size paper will be described. When the plate making start key is pressed, a document image reading operation is performed in the image reading unit 7, and the read document image passes through the lens 44, the image sensor 45, and an A / D converter (not shown) and then the document 1. It is stored in the image memory 105 as image data signals for the number of sheets. When this large size paper is used, the control unit 108 does not determine whether a solid image portion exists in the original image. Then, an operation program for a large-size sheet is read that is executed at a position where the ejection of air to the sheet P from the peeling member 47 corresponds to the leading end of the sheet and a position approximately corresponding to the middle of the length of the sheet P in the sheet conveyance direction. . The operation of the stencil printing apparatus 107 in this case is the same as the operation of the stencil printing apparatus 1 when a large-size sheet is used in the first embodiment.

  According to the above-described configuration, when a small-size paper is used and a document that does not have a solid image portion is printed, a solid image is obtained when the small-size paper is used at a position corresponding to the leading edge of the paper. The peeling member 47 is positioned at a position corresponding to the leading edge of the sheet and the solid image area when printing a document having a portion, and at a position corresponding to the central portion of the leading edge of the sheet and the conveyance direction of the sheet when using a large size sheet. Since the air is ejected from the opening 47c, even if the paper P has a solid image portion extending almost to the entire surface or to the rear side of the central portion in the paper conveyance direction, the plate cylinder is caused by the adhesive force of the ink. The paper P attached to the master 26 on the outer peripheral surface can be peeled off satisfactorily, and the paper P has a defect that causes nail mark stains or the paper P gets stuck in the peeling member 47 and is jammed. To prevent the occurrence of problems that would cause it is possible to obtain good prints.

  In the present embodiment, when a small-size paper is used and a document that does not have a solid image portion is printed, the piston 50 makes one reciprocation within the cylinder 49 during one rotation of the plate cylinder 9, and when a small-size paper is used. When printing a document having a solid image portion and when using a large size paper, the piston 50 reciprocates twice within the cylinder 49 during one rotation of the plate cylinder 9, and the rotational peripheral speed of the plate cylinder 9 depends on the printing speed. Since the speed can be changed, the reciprocating speed of the piston 50 is intermittent with the rotational peripheral speed of the piston drive motor 71 as a constant speed so as to be a constant speed that is twice or more the maximum rotational peripheral speed of the plate cylinder 9. The control is performed so as to be rotationally driven.

  Note that the rotational peripheral speed of the piston drive motor 71 may be changed in accordance with the rotational peripheral speed of the plate cylinder 9, but in this case, when the plate cylinder 9 is rotated at a low speed, such as during the printing operation, the piston The moving speed of the motor 50 is also reduced, and the air ejection pressure from the opening 47c may be reduced to prevent good separation. In such a case, the rotational peripheral speed of the piston drive motor 71 is appropriately increased, It is necessary to make it the structure which keeps the ejection pressure of the air from the opening 47c more than a fixed value.

  Next, a sixth embodiment of the present invention will be described. The sixth embodiment is different from the fifth embodiment described above only in that an air supply unit 76 is used instead of the air supply unit 48, and the other configurations are the same. The operation of the stencil printing apparatus 107 in the sixth embodiment will be described below.

  When the plate making start key is pressed by the operator, the control means 108 confirms the size of the paper P stacked on the paper feed tray 29 based on the paper size detection signal from the paper size detection sensor 34. First, a case where the paper P is a small size paper will be described.

  When the plate making start key is pressed, a document image reading operation is performed in the image reading unit 7, and the read document image passes through the lens 44, the image sensor 45, and an A / D converter (not shown) and then the document 1. It is stored in the image memory 105 as image data signals for the number of sheets. When an image data signal for one document is stored in the image memory 105, the control unit 108 determines whether or not there is a solid image portion in the document image, as in the fifth embodiment.

  At this time, if it is determined that there is no solid image portion in the original image, the ejection of air from the peeling member 47 to the paper P is performed only at a position corresponding to the front end portion of the paper. When the operation program is read and it is determined that the original image has a solid image portion, the ejection of air from the peeling member 47 to the paper P is performed at a position corresponding to the front end portion of the paper and a position corresponding to the solid image portion. The operation program for the presence of a solid image portion of size paper is read.

  The operation of the stencil printing apparatus 107 when there is no small-size sheet solid image portion is the same as the operation of the stencil printing apparatus 1 when the small-size sheet is used in the second embodiment. The operation of the stencil printing apparatus 107 is the same as the operation of the stencil printing apparatus 104 with a solid image portion in the fourth embodiment.

  Next, a case where the paper P is a large size paper will be described. When the plate making start key is pressed, a document image reading operation is performed in the image reading unit 7, and the read document image passes through the lens 44, the image sensor 45, and an A / D converter (not shown) and then the document 1. It is stored in the image memory 105 as image data signals for the number of sheets. When this large-size sheet is used, as in the fifth embodiment, the control unit 108 does not determine whether a solid image portion exists in the document image. Then, an operation program for a large-size sheet is read that is executed at a position where the ejection of air to the sheet P from the peeling member 47 corresponds to the leading end of the sheet and a position approximately corresponding to the middle of the length of the sheet P in the sheet conveyance direction. . The operation of the stencil printing apparatus 107 in this case is the same as the operation of the stencil printing apparatus 1 when using large-size paper in the second embodiment.

  According to the above-described configuration, when a small-size paper is used and a document that does not have a solid image portion is printed, a solid image is obtained when the small-size paper is used at a position corresponding to the leading edge of the paper. The peeling member 47 is positioned at a position corresponding to the leading edge of the sheet and the solid image area when printing a document having a portion, and at a position corresponding to the central portion of the leading edge of the sheet and the conveyance direction of the sheet when using a large size sheet. Since air is ejected from the opening 47c, the same effects as those of the fifth embodiment can be obtained.

  In the present embodiment, when printing a document that is small-size paper and does not have a solid image portion, one of the pistons 78 and 84 corresponds to one of the pistons 78 and 84 during one rotation of the plate cylinder 9. , 83 one reciprocation, when using a small size paper and printing a document having a solid image portion and when using a large size paper, each piston 78, 84 corresponds to a corresponding cylinder 77, during one rotation of the plate cylinder 9. Since the rotational speed of the plate cylinder 9 can be changed according to the printing speed, the reciprocating speed of the pistons 78 and 84 is higher than the maximum rotational peripheral speed of the plate cylinder 9. Control is performed so that the rotational peripheral speeds of the piston drive motors 92 and 95 are intermittently driven at a constant speed so that the speed is constant.

  The rotational peripheral speed of each of the piston drive motors 92 and 95 may be changed in accordance with the rotational peripheral speed of the plate cylinder 9, but in this case, the plate cylinder 9 is rotated at a low speed such as during the plate-making operation. In this case, the moving speed of the pistons 78 and 84 is also reduced, and the air ejection pressure from the opening 47c may be reduced to prevent good separation. In this case, the piston drive motors 92 and 95 It is necessary to make it the structure which raises the rotation peripheral speed of this suitably, and maintains the jet pressure of the air from the opening 47c more than a fixed value.

  In the fifth and sixth embodiments described above, the piston 50 is reciprocated by the piston drive motor 71, the first piston 78 is moved by the first piston drive motor 92, and the second piston 84 is moved by the second piston drive motor 95. However, the piston driving motors 71, 92, and 95 are not used, and the rotational driving force from the plate cylinder driving means 58 is transmitted by driving force transmission means such as a gear or a belt, and the pistons 50, 78, and 84 are transmitted. It is good also as a structure which reciprocates.

  When this configuration is adopted in the fifth embodiment, when a small-size paper is used and a document having no solid image portion is printed, the piston 50 is reciprocated once during one rotation of the plate cylinder to reduce the small size paper. When using size paper and printing a document having a solid image portion or using large size paper, the piston 50 needs to be reciprocated twice during one rotation of the plate cylinder. There are two paths: a path for transmitting the rotational driving force for one rotation of the cylinder as a driving force for one reciprocation of the piston, and a path for transmitting the driving force while increasing the driving force for two pistons. The transmission path needs to be switched.

  In both the fifth and sixth embodiments, the position of the paper P is the same as the position corresponding to the solid image portion when a document having a solid image portion is used when the small size paper is used and the large size paper is used. Since it is necessary to eject air at a position approximately in the middle of the transport direction, it is necessary to change the location of the air ejection according to the position of the solid image portion or the length of the paper P in the paper transport direction. In this case, it is necessary to control the reciprocating motion of each piston 50, 78, 84 by using a disconnecting means such as a clutch for connecting or disconnecting the driving force as the driving force transmitting means.

  FIG. 12 shows a stencil printing apparatus capable of double-sided printing employing the seventh embodiment of the present invention. Since this stencil printing apparatus 201 has substantially the same configuration as the double-sided printing apparatus disclosed in Japanese Patent Application Laid-Open No. 2003-200355 except for a part thereof, description of each part is simplified as much as possible.

  The stencil printing apparatus 201 includes a printing unit 202, a plate making unit 203, a paper feeding unit 204, a plate discharging unit 205, a paper discharging unit 206, an image reading unit 207, an auxiliary tray 208, a refeeding unit 209, a first peeling member 210, a first one. 2 having a peeling member 211 and the like.

  A printing unit 202 disposed substantially at the center of the apparatus main body includes a plate cylinder 212 and a press roller 213 as pressing means. The plate cylinder 212 is rotatably supported by the apparatus main body and is driven to rotate by a plate cylinder driving means (not shown). The plate cylinder 212 has an openable and closable clamper on its outer peripheral surface, and a master 221 that has been made by the plate making unit 203 is wound around the outer peripheral surface thereof.

  The master 221 that has been made by the plate making unit 203 includes a first plate making image corresponding to the front surface image, a second plate making image corresponding to the back surface image, and an unmade portion formed between the plate making images during double-sided printing. In the single-side printing, the pre-made masters on which the third plate-making image for single-sided printing is formed are respectively made. The divided plate-making master is wound on the plate cylinder 212 so that the first plate-making image corresponds to the front surface region shown in FIG. 12, the second plate-making image corresponds to the same back surface region, and the non-plate-making portion corresponds to the same intermediate region. Is done. The prepress master is wound so that the third prepress image falls within a range in which all of the above-described front surface region, intermediate region, and back surface region are combined.

  A well-known ink supply means (not shown) is disposed inside the plate cylinder 212, and a rotary encoder (not shown) for detecting the position of the plate cylinder 212 is provided in the vicinity of the outer peripheral surface of the plate cylinder 212.

  A press roller 213 is disposed below the plate cylinder 212. The press roller 213 made of an elastic body having water repellency such as a fluororesin is rotatably supported at both ends by an arm member (not shown) that is swung by a swinging means (not shown). The press roller 213 selectively selects the separation position shown in FIG. 1 where the outer circumferential surface is separated from the plate cylinder 212 by the operation of a swinging means (not shown) and the pressure contact position where the circumferential surface is pressed against the master 221 on the plate cylinder 212. Occupy.

  Further, the swinging means (not shown) has a pressing range of the press roller 213 with respect to the plate cylinder 212 in the same range as the first range and the surface range, which are all the surface area, intermediate area, and back area shown in FIG. The second range is configured to be switchable to any one of the third range including the downstream portion of the front surface region, the intermediate region, and the back surface region. In the vicinity of the peripheral surface of the press roller 213, a cleaning roller 215 that performs cleaning by contacting the outer peripheral surface of the press roller 213 is disposed. The cleaning roller 215 is rotationally driven by a driving unit (not shown).

  Near the right side of the press roller 213, a refeed guide member 216 for conveying the surface printed paper PA sent from the refeed unit 209 along the outer peripheral surface of the press roller 213 is disposed. A re-feeding registration roller 217 is disposed below the press roller 213 and sends out the surface-printed paper PA stored on the auxiliary tray 208 in contact with the outer peripheral surface of the press roller 213. A refeed conveyance member 218 having an auxiliary tray 208 on the upper surface is disposed on the lower left side of the press roller 213, and a refeed positioning member 219 is provided integrally therewith. A sheet receiving plate 220 that is movable along the upper surface of the auxiliary tray 208 is disposed above the refeed conveyance member 218. The auxiliary tray 208, the refeed guide member 216, the refeed registration roller 217, the refeed positioning member 219, the refeed transport member 218, and the sheet receiving plate 220 constitute a refeed unit 209.

  A plate making unit 203 is disposed on the upper right side of the printing unit 202. The plate making unit 203 includes a master holding member 222 that holds a master roll obtained by winding the master 221 in a roll shape, a platen roller 223, a thermal head 224, a master cutting unit 225, a master stock unit 226, a tension roller pair 227, and a reverse roller pair. In the plate making unit 203, a plate-making master is created at the time of single-sided printing, and a divided plate-making master is created at the time of double-sided printing.

  A sheet feeding unit 204 is disposed below the plate making unit 203. The paper feed unit 204 includes a paper feed tray 229, a paper feed roller 230, a separation roller 231, a separation pad 232, a registration roller pair 233, and the like. The paper feed tray 229 on which the paper P is stacked is provided with a plurality of paper size detection sensors 234 for detecting the size of the paper P.

  The plate discharging unit 205 disposed on the upper left side of the printing unit 202 also has a well-known configuration including an upper plate discharging member 235, a lower plate discharging member 236, a plate discharging box 237, a compression plate 238, and the like. It is peeled off from the outer peripheral surface of 212 and discarded inside the discharge box 237.

  A paper discharge unit 206 is disposed below the plate discharge unit 205. The paper discharge unit 206 includes a paper discharge conveyance member 239, a paper discharge tray 240, and the like. The paper discharge conveyance member 239 has a driving roller, a driven roller, an endless belt, a suction fan, and the like, and conveys the printed paper PB in the direction of the arrow in FIG. The paper discharge tray 240 has one end fence and a pair of side fences, and the printed paper PB is stacked on the upper surface thereof.

  An image reading unit 207 is disposed on the upper part of the apparatus main body. The image reading unit 207 includes a contact glass 241 on which an original is placed, a pressure plate 242 provided so as to be able to contact with and separate from the contact glass 241, reflection mirrors 243, 244, 245, 246 for scanning and reading an original image, and a fluorescent lamp. 247, a lens 248 for focusing the scanned image, an image sensor 249 for processing the focused image, an image memory 214, and the like.

  A dog 250 is attached near the outer peripheral edge of an end plate (not shown) constituting the plate cylinder 212, and a home position sensor 251 is provided on the circular track of the dog 250 that moves as the plate cylinder 212 rotates. Yes. The home position sensor 251 detects the dog 250 when the plate cylinder 212 occupies the home position shown in FIG. 12, and the detection signal is sent to the control means 280 described later.

  In the vicinity of the outer peripheral surface of the plate cylinder 212 and between the press roller 213 and the paper discharge conveyance member 239, the surface-printed paper PA is peeled off from the outer peripheral surface of the plate cylinder 212 during double-sided printing, and the auxiliary tray. A first peeling member 210 for guiding to 208 is disposed.

  As shown in FIG. 13, the first peeling member 210 has a substantially triangular shape in a side view having a through hole 210d, and one end thereof is attached to a support shaft 210a that is swingably supported by the apparatus main body. . The other end side of the first peeling member 210 has an acute angle shape, and an opening 210c, which is a first jet port, is formed at the tip portion 210b. The first peeling member 210 is swung at the time of double-sided printing by a first peeling member rocking means (not shown), and the leading edge portion 210b is separated from the outer peripheral surface of the plate cylinder 212. It selectively occupies the proximity position indicated by the two-dot chain line in FIG.

  A first peeling member swinging means (not shown) transmits a driving force from a plate cylinder driving means (not shown) by a driving force transmission means (not shown), and swings the first peeling member 210 in synchronization with the rotation of the plate cylinder 212. . Note that the operation of the first peeling member oscillating means (not shown) is stopped during single-sided printing, and the first peeling member 210 is fixed at the separated position.

  A first air supply means 252 is connected to the first peeling member 210. The first air supply means 252 includes a first cylinder 253, a first piston 254 that can reciprocate inside the first cylinder 253, one end connected to the air discharge port 253 a of the first cylinder 253, and the other end to the first peeling member. 210 is composed mainly of an air hose 255 connected to one end of the 210, a first rotating plate 256, a first link 257 attached at one end to the periphery of the first rotating plate 256 and the other end attached to the first piston 254, and the like. Yes.

  The first cylinder 253 is supported by the apparatus main body, and the first rotating plate 256 is attached to a support shaft 258 that is rotatably supported by the apparatus main body. As shown in FIG. 14, a timing pulley 259 is attached to the support shaft 258, and the timing pulley 259 is fixed to an output shaft of a first piston drive motor 260 as a drive motor that is a stepping motor attached to the apparatus main body. The pinion 261 and the timing belt 262 are drivingly connected. A dog 263 is attached to the periphery of the first rotating plate 256, and this dog 263 is detected by a first rotating plate position detection sensor 264 as a rotating plate position detecting means attached to the apparatus main body. The arrangement positions of the dog 263 and the first rotary plate position detection sensor 264 will be described later.

  With the configuration described above, the rotational force of the first piston drive motor 260 is transmitted to the support shaft 258 via the pinion 261, the timing belt 262, and the timing pulley 259, and the rotational force of the support shaft 258 is transmitted to the first rotary plate 256, the first By being transmitted to the first piston 254 via the link 257, the first piston 254 is reciprocated in the first cylinder 253. These first rotary plate 256, first link 257, support shaft 258, timing pulley 259, first piston drive motor 260, pinion 261, and timing belt 262 constitute a first piston drive means 265.

  Here, the arrangement positions of the dog 263 and the first rotary plate position detection sensor 264 will be described. As described above, the first air supply means 252 receives the driving force from the first piston drive motor 260 and ejects air from the opening 210c. In this stencil printing apparatus 201, the timing of ejecting air from the opening 210c is double-sided. The sheet P fed from the sheet feeding unit 204 is pressed by the press roller 213 against the first plate-making image of the master (divided plate-making master) 221 wound on the plate cylinder 212 at the time of printing. It is determined when the leading edge of the paper P occupies a position corresponding to the opening 210c when being peeled from the plate cylinder 212 by the one peeling member 210.

  Therefore, the first piston drive motor 260 has an opening at the front end of the sheet P fed from the paper supply unit 204, that is, the front end of the first plate-making image of the divided plate-making master 221 wound on the plate cylinder 212. When the first piston 254 occupies a position corresponding to 210c, the first piston 254 is located at the leftmost side in FIG. 13 in the first cylinder 253 and then moved slightly to the right in FIG. When one piston 254 is located on the leftmost side in the first cylinder 253, the air ejection pressure from the opening 210c becomes maximum, but the air is supplied to the first peeling member 210 through the air hose 255, so that the timing slightly deviates. The first rotary plate 256 is actuated to rotate. The first rotary plate position detection sensor 264 and the dog 263 are positioned so that the first rotary plate position detection sensor 264 detects the dog 263 when the first piston 254 occupies the position indicated by the two-dot chain line in FIG. Respectively.

  The printed paper PB is peeled off from the outer peripheral surface of the plate cylinder 212 in the vicinity of the outer peripheral surface of the plate cylinder 212 and between the plate discharging unit 205 and the paper discharge unit 206 during single-sided printing and double-sided printing. A second peeling member 211 for guiding to the paper discharge conveying member 239 is provided.

  As shown in FIG. 15, the second peeling member 211 has a square pipe shape with both ends opened, and one end of the second peeling member 211 is attached to a support shaft 211a that is swingably supported by the apparatus main body. The other end side of the second peeling member 211 is formed so as to be gradually narrowed from about the middle, and the tip end portion 211b is formed so as to protrude from the opening 211c which is the second ejection port. The second peeling member 211 is swung by a second peeling member swinging means (not shown), and the front end portion 211b is located close to the outer peripheral surface of the plate cylinder 212, and an obstacle such as a clamper on the plate cylinder 212. In order to avoid this, the front end portion 211b selectively occupies a position away from the outer peripheral surface of the plate cylinder 212.

  The second peeling member swinging means (not shown) transmits the driving force from the plate cylinder driving means (not shown) by the driving force transmission means (not shown), and swings the second peeling member 211 in synchronization with the rotation of the plate cylinder 212. .

  A second air supply means 266 is connected to the second peeling member 211. The second air supply means 266 includes a second cylinder 267, a second piston 268 capable of reciprocating inside the second cylinder 267, one end connected to the air discharge port 267a of the second cylinder 267, and the other end to the second peeling member. 211 is mainly composed of an air hose 269 connected to one end of the 211, a second rotary plate 270, a second link 271 attached to one end of the second rotary plate 270 and the other end attached to the second piston 268, and the like. Yes.

  The second cylinder 267 is supported by the apparatus main body, and the second rotating plate 270 is attached to a support shaft 272 that is rotatably supported by the apparatus main body. A timing pulley 273 is attached to the support shaft 272 as shown in FIG. 16, and the timing pulley 273 is fixed to an output shaft of a second piston drive motor 274 as a drive motor which is a stepping motor attached to the apparatus main body. The pinion 275 and the timing belt 276 are drivingly connected. A dog 277 is attached to the peripheral edge of the second rotary plate 270, and this dog 277 is detected by a second rotary plate position detection sensor 278 as a rotary plate position detecting means attached to the apparatus main body. The arrangement positions of the dog 277 and the second rotary plate position detection sensor 278 will be described later.

  With the above-described configuration, the rotational force of the second piston drive motor 274 is transmitted to the support shaft 272 via the pinion 275, the timing belt 276, and the timing pulley 273, and the rotational force of the support shaft 272 is transmitted to the second rotating plate 270 and the second rotation plate 270. By being transmitted to the second piston 268 via the link 271, the second piston 268 is reciprocated in the second cylinder 267. The second rotary plate 270, the second link 271, the support shaft 272, the timing pulley 273, the second piston drive motor 274, the pinion 275, and the timing belt 276 constitute a second piston drive means 279.

  Here, the arrangement positions of the dog 277 and the second rotary plate position detection sensor 278 will be described. As described above, the second air supply means 266 is transmitted with driving force from the second piston drive motor 274 and ejects air from the opening 211c. In this stencil printing apparatus 201, the timing of ejecting air from the opening 211c is one side. After the sheet P fed from the sheet feeding unit 204 is pressed by the press roller 213 against the third plate-making image of the master (plate-making master) 221 wound on the plate cylinder 212 at the time of printing, the second is applied. When the leading end of the paper P that has become the printed paper PB when it is peeled off from the plate cylinder 212 by the peeling member 211 occupies a position corresponding to the opening 211c, and wound on the plate cylinder 212 at the time of duplex printing The surface-printed paper PA fed from the re-feeding means 209 to the second plate-making image of the master (divided plate-making master) 221 is a press roller. 13, when the front end portion of the surface-printed paper PA that has become the printed paper PB when being peeled from the plate cylinder 212 by the second peeling member 211 occupies a position corresponding to the opening 211 c. It has been established.

  Therefore, the second piston drive motor 274 is substantially the same as the leading end portion of the paper P fed from the paper feed unit 204 at the time of single-sided printing, that is, the third plate-making image of the plate-making master 221 wound on the plate cylinder 212. At the time of double-sided printing, the leading edge of the paper P fed from the refeed unit 209, that is, the substantially leading edge of the second plate-making image of the divided plate-making master 221 wound on the plate cylinder 212 is used. The position indicated by the two-dot chain line in FIG. 15 is the position where the second piston 268 has moved to the right side after being positioned at the leftmost side in FIG. 15 in the second cylinder 267 when the position corresponding to the opening 211c is occupied. (When the second piston 268 is located on the leftmost side in the second cylinder 267, the air ejection pressure from the opening 211c becomes the maximum, but the second peeling member 211 is passed through the air hose 269. So as to occupy little deviation occurs in the timing) to the gas is supplied and operates the second rotation plate 270 so as to rotate. The second rotary plate position detection sensor 278 and the dog 277 are positioned such that the second rotary plate position detection sensor 278 detects the dog 277 when the second piston 268 occupies the position indicated by the two-dot chain line in FIG. Respectively.

  FIG. 17 is a block diagram of control means used in the stencil printing apparatus 201. In the figure, the control means 280 is constituted by a microcomputer having a CPU, ROM, RAM, etc. therein, and is provided inside the apparatus main body.

  The control means 280 receives various signals from the operation panel 281 provided on the upper front surface of the apparatus main body, various sensors such as the first rotary plate position detection sensor 264, the second rotary plate position detection sensor 278, and the home position sensor 251. Based on the signal and the operation program stored in advance, the printing unit 202, the plate making unit 203, the paper feeding unit 204, the plate discharging unit 205, the paper discharging unit 206, the image reading unit 207, the refeeding unit 209, the first air supply The operations of the means 252 and the second air supply means 266 are controlled to control the operation of the stencil printing apparatus 201 as a whole.

Based on the above configuration, the operation of the stencil printing apparatus 201 in the seventh embodiment will be described below. First, a case where single-sided printing is set on the operation panel 281 will be described.
The operator stacks the paper P to be used for printing on the paper feed tray 229, opens the pressure plate 242 and places a document to be printed on the contact glass 241, and then closes the pressure plate 242 again. Thereafter, the plate making conditions are set by various keys on the operation panel 281 and then the plate making start key is pressed. When the plate making start key is pressed, the image reading unit 207 performs a document image reading operation. The read document image is converged by the lens 248 and then incident on the image sensor 249 to be photoelectrically converted, and then not shown. Input to the A / D converter.

  In parallel with the image reading operation in the image reading unit 207, the plate discharging unit 205 performs a plate discharging operation for peeling the used master 221 from the outer peripheral surface of the plate cylinder 212. When the plate making start key is pressed, the plate cylinder 212 starts to rotate, and when the plate cylinder 212 reaches the home position with the clamper directly below, the dog 250 is detected by the home position sensor 251 and the home position sensor 251 controls the means. A home position signal is sent to 280. The control means 280 that has received the home position signal detects the position of the plate cylinder 212 based on a signal from a rotary encoder (not shown) with this home position as a base point, and is used wound around the outer peripheral surface of the plate cylinder 212. When it is determined that the front end of the master 221 has reached a predetermined plate discharging position corresponding to the lower plate discharging member 236, the rotation of the plate cylinder 212 is stopped.

  When the plate cylinder 212 stops at a predetermined plate discharge position, the lower plate discharge member 236 moves to the plate cylinder 212 side, and the used master 221 is peeled from the plate cylinder 212. The used master 221 that has been peeled off is conveyed into the plate discharge box 237 by the plate discharge members 235 and 236 and compressed by the compression plate 238. When the plate discharging operation is completed, the plate cylinder 212 rotates and stops to the plate supply standby position where the clamper faces substantially rightward. The clamper is released and the stencil printing apparatus 201 enters the plate supply standby state.

  In parallel with the image reading operation, the plate making unit 203 performs the plate making operation. When the plate making start key is pressed, the platen roller 223 and the tension roller pair 227 are rotated and the master 221 is pulled out from the master roll. When the image forming area of the master 221 reaches a position corresponding to the heat generating element of the thermal head 224, each heat generation of the thermal head 224 is performed based on an image data signal sent from the image sensor 249 via an A / D converter (not shown). The element selectively generates heat, and a third plate-making image is formed on the master 221.

  The master 221 that has formed the third plate-making image and has become a plate-making master is stored in the master stock unit 226 by the rotation of the tension roller pair 227. When the plate discharging operation is completed and the plate cylinder 212 is stopped at the plate feed standby position, the reverse roller pair 228 starts rotating, and the plate-making master 221 is conveyed from the master stock unit 226. When the leading end of the master 221 is transported to a position where it can be clamped by the clamper, the clamper is closed and the master 221 is held on the outer peripheral surface of the plate cylinder 212.

  Thereafter, the plate cylinder 212 is intermittently rotated in the clockwise direction in FIG. 12, and the plate-making master 221 is wound around the plate cylinder 212. When the image data signal is interrupted, the operation of the thermal head 224 is stopped, and when it is determined that one plate-making master 221 has been created, the platen roller 223, the tension roller pair 227, and the reverse roller pair 228 are rotated. At the same time, the master cutting means 225 is activated and the master 221 is cut. After being cut, the master 221 is drawn out of the plate making unit 203 by the rotation of the plate cylinder 212, and the plate cylinder 212 is rotated to the home position and stopped to complete the plate making operation and the plate feeding operation.

  The printing operation is performed following the plate feeding operation. When the plate cylinder 212 stops at the home position, the paper feed roller 230, the separation roller 231 and the paper discharge conveyance member 239 are driven, and the plate cylinder 212 is driven to rotate in the clockwise direction in FIG. After that, only one sheet P positioned at the top is pulled out from the sheet feed tray 229, and the leading end of the pulled sheet P is sandwiched between the registration roller pair 233. The registration roller pair 233 is driven to rotate at a predetermined timing when the leading edge of the third plate-making image in the plate-cylinder rotation direction of the plate-making master 221 wound on the plate cylinder 212 reaches a position corresponding to the press roller 213. The drawn paper P is fed between the plate cylinder 212 and the press roller 213. In this single-sided printing, a swinging means (not shown) that swings the press roller 213 sets the pressing range of the press roller 213 against the plate cylinder 212 to the first range.

  The fed paper P is pressed by the press-making master 221 wound around the outer peripheral surface of the plate cylinder 212 by the press roller 213. As a result, the ink supplied from the ink supply means (not shown) to the inner peripheral surface of the plate cylinder 212 oozes out from the opening of the plate cylinder 212, and the porous support plate (not shown), the mesh screen (not shown), and the perforated master 221 After filling the adhesive support, it is transferred to the paper P through the punching portion of the third plate-making image of the plate-making master 221, so-called printing is performed.

  The sheet P that has been formed with a printing image corresponding to the third plate-making image by printing and becomes a printed sheet PB is peeled off from the plate-making master 221 on the outer peripheral surface of the plate cylinder by the second peeling member 211. . At the time of peeling, the second piston driving motor 274 is operated, and the second piston 268 reciprocates once in the second cylinder 267, whereby air is ejected from the opening 211c, and the printed paper PB is peeled from the outer peripheral surface of the plate cylinder. Is done well.

  The operation of the second piston drive motor 274 is based on a plate cylinder angle signal from a rotary encoder (not shown), and the leading end of the printed paper PB that is in pressure contact with the third plate-making image reaches a position corresponding to the opening 211c. The second rotating plate position detection sensor 278 is sometimes controlled by the control means 280 so as to detect the dog 277. Under the control of the control means 280, air is blown out from the opening 211c between the leading end of the printed paper PB and the master 221 on the outer peripheral surface of the plate cylinder. The peeled printed paper PB falls downward and is received by the paper discharge transport member 239, and then transported and discharged onto the paper discharge tray 240. Thereafter, after the plate cylinder 212 is rotated to the home position again, the rotation of the plate cylinder 212 is stopped, and the stencil printing apparatus 201 enters a single-sided printing standby state after finishing the plate attaching operation.

  After the stencil printing apparatus 201 enters the single-sided printing standby state, when a trial printing key is pressed after inputting printing conditions using various keys on the operation panel 281, trial printing is performed. When the trial printing key is pressed, the plate cylinder 212 is driven to rotate at a peripheral speed corresponding to the set printing speed, and one sheet P is fed from the paper feeding unit 204. The fed paper P is temporarily stopped by the registration roller pair 233 and then fed toward the printing unit 202 at the same timing as the plate printing. The press roller 213 presses the master 221 on the outer periphery of the plate cylinder. Is done. The paper P that has been formed with the print image and becomes the printed paper PB is peeled off from the master 221 on the outer peripheral surface of the plate cylinder by the second peeling member 211 and sent to the paper discharge unit 206. It is conveyed and discharged onto the discharge tray 240. Even during the trial printing, when the printed paper PB is peeled from the outer peripheral surface of the plate cylinder, air is sent from the second air supply unit 266 in the same manner as described above, and the printed paper PB is peeled well.

  When the print start key is pressed after setting the number of prints after confirming the image position or image density, etc. by trial printing, the paper P is continuously fed from the paper supply unit 204 and single-sided printing is performed in the same way as during trial printing. Operation is performed. When the set number of prints is consumed, the plate cylinder 212 stops at the home position, and the stencil printing apparatus 201 enters the single-sided printing standby state again. Even during this single-sided printing operation, when the printed paper PB is peeled from the outer peripheral surface of the plate cylinder, air is sent from the second air supply means 266 in the same manner as described above, and the printed paper PB is favorably peeled off. .

Next, a case where duplex printing is set on the operation panel 281 will be described.
When the operator presses the plate-making start key after the first document is set on the contact glass 241, the image reading unit 207 performs a reading operation in the same way as during single-sided printing, and the read image is stored in the image memory. The first image data signal is stored in 214. Thereafter, when the second original is set on the contact glass 241 and the pressure plate 242 is closed, the reading operation is performed in the same manner, and the read image is stored in the image memory 214 as the second image data signal. Is done.

  In parallel with the image reading operation in the image reading unit 207, the plate discharging unit 205 performs a plate discharging operation in the same manner as in single-sided printing. The plate cylinder 212 from which the used master 221 has been peeled off from the outer peripheral surface is stopped at the plate feed standby position, and the clamper is opened by the operation of an opening / closing means (not shown). In parallel with the plate discharging operation, the plate making unit 203 performs the plate making operation. This plate making operation is performed in the same procedure as described above, but the first plate making image, the second plate making image, and an unmade portion located between the images are formed in the master 221.

  The master 221 that has formed each image and the unengraved portion and becomes the divided engraving master is stored in the master stock unit 226, and when the stencil printing apparatus 201 is in a plate feeding standby state after the plate discharging operation is completed, the reversing roller pair The divided master-making master 221 is conveyed toward the plate cylinder 212 by the operation of 228. Thereafter, the plate cylinder 212 is intermittently rotated in the same manner as described above, and the divided plate-making master 221 is wound around the plate cylinder 212. When all the image data for the two originals is sent from the image memory 214, the master cutting means 225 is activated and the master 221 is cut. After being cut, the divided plate-making master 221 is pulled out from the plate-making unit 203 by the rotation of the plate cylinder 212, and the plate cylinder 212 rotates to the home position and stops, whereby the plate-making operation and the plate-feeding operation are completed.

  The printing operation is performed following the plate feeding operation. When the plate cylinder 212 stops at the home position, the paper feed roller 230, the separation roller 231 and the paper discharge conveyance member 239 are driven, and the plate cylinder 212 is driven to rotate in the clockwise direction in FIG. Thereafter, only one sheet P positioned on the top of the sheet feed tray 229 is pulled out, and the leading end of the pulled sheet P is sandwiched between the registration roller pair 233.

  Then, when the clamper passes the position corresponding to the first peeling member 210, the first peeling member 210 is positioned in the proximity position, and then the divided plate-making master 221 wound on the plate cylinder 212 in the plate cylinder rotation direction. The registration roller pair 233 is rotationally driven at a predetermined timing when the leading edge of the first plate-making image reaches a position corresponding to the press roller 213, and the paper P is fed toward the space between the plate cylinder 212 and the press roller 213. . At this time, the swinging means (not shown) that swings the press roller 213 sets the pressing range of the press roller 213 against the plate cylinder 212 to the second range.

  The fed paper P is pressed by the press roller 213 against the first plate-making image of the divided plate-making master 221 wound around the outer peripheral surface of the plate cylinder 212. As a result, the ink supplied from the ink supply means (not shown) to the inner peripheral surface of the plate cylinder 212 oozes out from the opening of the plate cylinder 212, and the porous support plate (not shown), the mesh screen (not shown), and the divided plate-making master 221. After filling the porous support, it is transferred to the paper P through the perforated part of the first plate-making image of the divided plate-making master 221, and the portion corresponding to the first plate-making image is printed.

  The sheet P, which has been formed on one side with a printing image corresponding to the first plate-making image by printing and becomes a surface-printed sheet PA, has been subjected to divided plate-making on the outer peripheral surface of the plate cylinder from the front end portion by the first peeling member 210. It is peeled off from the master 221. At the time of peeling, the first piston driving motor 260 is operated, and the first piston 254 reciprocates once in the first cylinder 253, whereby air is ejected from the opening 210c, and the surface printed paper PA from the outer peripheral surface of the plate cylinder is discharged. Peeling is performed well.

  The operation of the first piston drive motor 260 reaches the position where the front end of the surface-printed paper PA in pressure contact with the first plate-making image reaches the position corresponding to the opening 210c with reference to a plate cylinder angle signal from a rotary encoder (not shown). The control means 280 controls the first rotary plate position detection sensor 264 to detect the dog 263. Under the control of the control means 280, air is jetted from the opening 210c between the front end of the surface-printed paper PA and the divided plate-making master 221 on the outer peripheral surface of the plate cylinder. The peeled surface-printed paper PA is dropped downward, one end which is the leading end in the dropping direction is received by the paper receiving plate 220, and is placed on the auxiliary tray 208. The surface-printed paper PA placed on the auxiliary tray 208 is transported in the direction of the arrow in FIG. 12 by the re-feeding transport member 218 and is temporarily stopped with the other end abutting against the re-feed positioning member 219. The

  The plate cylinder 212 continues to rotate while the surface-printed paper PA is guided onto the auxiliary tray 208, and the first peeling member until the clamper occupies a position corresponding to the first peeling member 210 again. 210 is displaced from the proximity position to the separation position. At this time, the swinging means (not shown) that swings the press roller 213 sets the pressing range of the press roller 213 against the plate cylinder 212 to the third range.

  Then, the re-feeding registration roller 217 is swung at a predetermined timing that is slightly earlier than the leading end of the second plate-making image of the divided plate-making master 221 reaches the position corresponding to the press roller 213, and the other end is moved. The surface-printed paper PA that has been held in contact with the re-feed positioning member 219 is pressed against the peripheral surface of the press roller 213.

  The surface-printed paper PA pressed against the peripheral surface of the press roller 213 by the re-feeding registration roller 217 is pressed against the peripheral surface of the plate cylinder 212 by the operation of a swinging means (not shown), and the rotation of the press roller 213 that is driven to rotate. The sheet is conveyed by force and conveyed toward the contact portion between the plate cylinder 212 and the press roller 213 in a state of being in close contact with the peripheral surface of the press roller 213 by the action of the sheet refeed guide member 216.

  The conveyed surface-printed paper PA is pressed against the second plate-making image of the divided plate-making master 221 wound around the outer peripheral surface of the plate cylinder 212 by the press roller 213. As a result, the ink supplied from the ink supply means (not shown) to the inner peripheral surface of the plate cylinder 212 oozes out from the opening of the plate cylinder 212, and the porous support plate (not shown), the mesh screen (not shown), and the divided plate-making master 221. After filling the porous support, it is transferred to the surface-printed paper PA through the perforated portion of the second plate-making image of the divided plate-making master 221, and the portion corresponding to the second plate-making image is printed.

  The surface-printed paper PA, which has been formed on the other side of the printed image corresponding to the second plate-making image by printing and becomes the printed paper PB, is divided on the outer peripheral surface of the plate cylinder from the front end portion thereof by the second peeling member 211. It is peeled off from the master 221 that has been made. At the time of peeling, the second piston driving motor 274 is operated, and the second piston 268 reciprocates once in the second cylinder 267, whereby air is ejected from the opening 211c, and the printed paper PB is peeled from the outer peripheral surface of the plate cylinder. Is done well.

  The operation of the second piston drive motor 274 is based on a plate cylinder angle signal from a rotary encoder (not shown), and the leading end of the printed paper PB that is in pressure contact with the second plate-making image reaches a position corresponding to the opening 211c. The second rotating plate position detection sensor 278 is sometimes controlled by the control means 280 so as to detect the dog 277. Under the control of the control means 280, air is ejected from the opening 211c between the leading end of the printed paper PB and the divided master-making master 221 on the outer peripheral surface of the plate cylinder. The peeled printed paper PB falls downward and is received by the paper discharge transport member 239, and then transported and discharged onto the paper discharge tray 240. After that, after the plate cylinder 212 is rotated to the home position again, the rotation of the plate cylinder 212 is stopped, and the stencil printing apparatus 201 enters a duplex printing standby state after finishing the plate attaching operation.

  After the stencil printing apparatus 201 enters the duplex printing standby state, the trial printing is performed when the trial printing key is pressed after inputting the printing conditions using the various keys on the operation panel 281. When the trial printing key is pressed, the plate cylinder 212 is driven to rotate at a peripheral speed corresponding to the set printing speed, and one sheet P is fed from the paper feeding unit 204. At this time, when the clamper passes a position corresponding to the first peeling member 210, the first peeling member 210 is positioned at the proximity position. The fed paper P is temporarily stopped by the registration roller pair 233 and then fed toward the printing unit 202 at the same timing as the plate printing. The press roller 213 causes the divided plate-making master 221 on the outer peripheral surface of the plate cylinder to be fed. The first plate making image is pressed. At this time, the swinging means (not shown) that swings the press roller 213 sets the pressing range of the press roller 213 against the plate cylinder 212 to the second range.

  The paper P on which the front surface printed image is formed and becomes the front surface printed paper PA is peeled from the divided master-made master 221 on the outer peripheral surface of the plate cylinder by the first peeling member 210 occupying the close position. Also at the time of peeling, air is sent from the first air supply means 252 in the same manner as at the time of printing, and the surface-printed paper PA is peeled well. The peeled surface-printed paper PA is dropped downward, one end of which is received by the paper receiving plate 220, and then placed on the auxiliary tray 208, and is transported by the re-feed transporting member 218 and the other end is re-recovered. It is temporarily stopped in a state where it is in contact with the paper feed positioning member 219.

  After that, the first peeling member 210 is displaced from the proximity position to the separation position as in the case of plate attachment, and the swinging means (not shown) sets the pressing range of the press roller 213 against the plate cylinder 212 to the third range. Then, the re-feeding registration roller 217 is swung at the same predetermined timing as that at the time of printing, and the surface-printed paper PA is pressed against the peripheral surface of the press roller 213. By this pressure contact, the surface-printed paper PA is conveyed toward the contact portion between the press roller 213 and the plate cylinder 212 by the rotational force of the press roller 213, and the second plate-making image of the divided plate-making master 221 on the outer peripheral surface of the plate cylinder. Pressure contacted.

  The front-side printed paper PA on which the back image is formed and becomes the printed paper PB is peeled off from the divided master-making master 221 on the outer peripheral surface of the plate cylinder by the second peeling member 211. Also at the time of peeling, air is sent from the second air supply means 266 in the same manner as at the time of printing, and the printed paper PB is peeled well. The peeled printed paper PB falls downward and is received by the paper discharge transport member 239, and then transported and discharged onto the paper discharge tray 240. Thereafter, the plate cylinder 212 is again rotated to the home position and stopped, and the stencil printing apparatus 201 is again in the duplex printing standby state.

  When the position or density of the image is confirmed by trial printing and the print start key is pressed after the number of prints is input on the operation panel 281, a printing operation is performed. In this embodiment, a case where N sheets are set as the number of printed sheets will be described.

  When the print start key is pressed, the plate cylinder 212 is driven to rotate at a peripheral speed corresponding to the set printing speed, and the first sheet P is fed from the paper supply unit 204. At this time, when the clamper passes a position corresponding to the first peeling member 210, the first peeling member 210 is positioned at the proximity position. The fed paper P is temporarily stopped by the registration roller pair 233 and then fed toward the printing unit 202 at the same timing as the plate printing. The press roller 213 causes the divided plate-making master 221 on the outer peripheral surface of the plate cylinder to be fed. The first plate making image is pressed. At this time, the swinging means (not shown) that swings the press roller 213 sets the pressing range of the press roller 213 against the plate cylinder 212 to the second range.

  The paper P on which the front surface printed image is formed and becomes the front surface printed paper PA is peeled from the divided master-made master 221 on the outer peripheral surface of the plate cylinder by the first peeling member 210 occupying the close position. Also at the time of peeling, air is sent from the first air supply means 252 in the same manner as at the time of printing and test printing, and the surface-printed paper PA is peeled off satisfactorily. The peeled surface-printed paper PA is dropped downward, one end of which is received by the paper receiving plate 220, and then placed on the auxiliary tray 208, and is transported by the re-feed transporting member 218 and the other end is re-recovered. It is temporarily stopped in a state where it is in contact with the paper feed positioning member 219.

  Thereafter, the second sheet P is fed from the sheet feeding unit 204, and the second sheet P is temporarily stopped by the registration roller pair 233 and then directed to the printing unit 202 at the same timing as the first sheet P. Are sent. The first peeling member 210 occupies a separated position so as to avoid a collision with the clamper, and then occupies a close position again after passing the clamper. At this time, the swinging means (not shown) sets the pressing range of the press roller 213 against the plate cylinder 212 to the first range.

  The fed second sheet P is pressed against the first plate-making image of the divided plate-making master 221 on the outer peripheral surface of the plate cylinder by the press roller 213, and the surface image is printed on one surface, and the second surface is printed. After becoming the printed paper PA, the first peeling member 210 occupying the proximity position peels from the front end of the divided plate-making master 221 on the outer periphery of the plate cylinder. Even at the time of peeling, air is sent from the first air supply means 252 and the second surface printed paper PA is peeled off satisfactorily. The peeled second surface-printed paper PA is dropped downward, one end of which is received by the paper receiving plate 220, then placed on the auxiliary tray 208, and transported by the refeed transporting member 218. The other end is temporarily stopped with the sheet re-feeding positioning member 219 in contact.

  The first surface-printed paper PA is pressed against the peripheral surface of the press roller 213 by the operation of the re-feeding registration roller 217, and the rear end of the second paper P is the plate cylinder 212, the press roller 213, and the like. After passing through the abutting portion of the sheet and becoming the second front surface printed paper PA, the intermediate region of the plate cylinder 212 passes through the position facing the press roller 213 and the back surface region faces the press roller 213. Is sent to the contact portion between the plate cylinder 212 and the press roller 213, and is pressed against the second plate-making image of the divided plate-making master 221 on the outer peripheral surface of the plate cylinder by the press roller 213, whereby the back image is formed on the other surface. Is printed and becomes the first printed paper PB.

  During the above-described operation, the first peeling member 210 is displaced from the proximity position to the separation position immediately before the intermediate area of the plate cylinder 212 occupies the position facing the press roller 213. Thus, the rear end of the second surface-printed paper PA guided by the first peeling member 210 passes through a slight gap between the lower surface of the first peeling member 210 and the peripheral surface of the press roller 213. The first surface-printed paper PA guided to the auxiliary tray 208 and subsequently conveyed by the refeeding means 209 passes through the first peeling member 210 occupying the separation position, and further rotates the plate cylinder. Sent downstream in the direction.

  Then, the first surface-printed paper PA that has been printed with the back image and becomes the first printed paper PB is divided by the second release member 211 from the front end portion thereof to the divided plate-making master 221 on the outer peripheral surface of the plate cylinder. More peeled. Even at the time of peeling, air is sent from the second air supply means 266, and the first printed paper PB is peeled well. The peeled first printed paper PB falls downward and is received by the paper discharge transport member 239, and then transported and discharged onto the paper discharge tray 240.

  After the second sheet P is guided onto the auxiliary tray 208, the third sheet P is fed from the sheet feeding unit 204, and the third sheet P is temporarily stopped by the registration roller pair 233. The sheet is fed toward the printing unit 2 at the same timing as the first and second sheets P. The first peeling member 210 occupies a separated position so as to avoid a collision with the clamper, and again occupies a close position after passing the clamper. The third sheet P fed is printed with a surface image on one side to become a third surface-printed sheet PA, and then the outer surface of the plate cylinder from the front end thereof by the first peeling member 210. It is peeled off from the upper divided master 221. Even at the time of peeling, air is sent from the first air supply means 252 and the third surface printed paper PA is peeled well. The peeled third surface-printed paper PA is dropped downward, and one end thereof is received by the paper receiving plate 220 and then guided onto the auxiliary tray 208.

  During the above-described operation, the re-feeding registration roller 217 is operated at a predetermined timing, and the second front surface printed paper PA stored on the auxiliary tray 208 is conveyed to the printing unit 2. The second front-side printed paper PA is sent to the contact portion between the plate cylinder 212 and the press roller 213 at the same timing as the first front-side printed paper PA, and the back side image is printed on the other side. Becomes the second printed paper PB. The first peeling member 210 is displaced from the proximity position to the separation position at the same timing as described above, and the rear end of the third surface printed paper PA is between the lower surface of the first peeling member 210 and the peripheral surface of the press roller 213. The second surface-printed paper PA that is guided to the auxiliary tray 208 through the slight gap and then conveyed by the paper refeeding means 209 passes through the first peeling member 210 that occupies the separation position. It passes through and is further sent downstream in the plate cylinder rotation direction.

  Then, the second preprinted paper PA that has been printed with the back image and becomes the second preprinted paper PB is divided by the second release member 211 from the leading end thereof to the divided preprinted master 221 on the outer peripheral surface of the plate cylinder. More peeled. Even at the time of peeling, air is sent from the second air supply means 266, and the second printed paper PB is peeled well. The peeled second printed paper PB falls downward and is received by the paper discharge transport member 239, and then transported and discharged onto the paper discharge tray 240.

  Thereafter, the same operation as described above is performed up to the (N−1) th sheet. Then, after the Nth sheet P is fed from the sheet feeding unit 204 and a surface image is printed on one surface thereof, and is guided onto the auxiliary tray 208 as the Nth surface printed sheet PA, ( (N-1) When the back side image is printed on the other side of the front-side printed paper PA and the (N-1) -th printed paper PB is discharged onto the paper discharge tray 240, it is not shown. The swinging means is switched, and the pressing range of the press roller 213 against the plate cylinder 212 is set to the third range. At this time, the first peeling member 210 occupies the separated position.

  Then, the sheet re-feeding registration roller 217 is operated at a predetermined timing similar to that described above, and the N-th surface printed sheet PA stored on the auxiliary tray 208 is conveyed to the printing unit 2. The Nth surface printed paper PA is sent to the contact portion between the plate cylinder 212 and the press roller 213 at the same timing as the first surface printed paper PA, and the back image is printed on the other surface. This is the Nth printed sheet PB. The N-th surface printed paper PA, which has been printed with the back image and becomes the N-th printed paper PB, is divided from the master plate 221 on the outer peripheral surface of the plate cylinder by the second peeling member 211 from the front end thereof. It is peeled off. Even at the time of peeling, air is sent from the second air supply means 266, and the Nth printed paper PB is peeled well.

  The peeled Nth printed paper PB falls downward and is received by the paper discharge transport member 239, and then transported and discharged onto the paper discharge tray 240. Thereafter, the plate cylinder 212 is rotated to the home position and stopped, and the stencil printing apparatus 201 finishes the duplex printing operation and enters the duplex printing standby state again.

  According to the above-described configuration, during single-sided printing, from the second peeling member 211 at a position corresponding to the front end of the paper, during double-sided printing, from the first peeling member 210 at a position corresponding to the front end of the paper during front-side printing, and from the backside printing Sometimes air is ejected from the second peeling member 211 at a position corresponding to the leading edge of the paper, so that it is possible to prevent the paper P from being rolled up on the plate cylinder 212 in both single-sided printing and double-sided printing. Peeling can be performed, and a good printed matter can be obtained in both single-sided printing and double-sided printing, and a good printing state can be maintained.

  In this embodiment, the second piston 268 reciprocates once in the second cylinder 267 during one rotation of the plate cylinder 212 during single-sided printing, and the first piston 254 moves during the first rotation of the plate cylinder 212 during double-sided printing. Since the second piston 268 reciprocates once in the second cylinder 267 and the rotational peripheral speed of the plate cylinder 212 can be changed according to the printing speed, the reciprocating speed of each piston 254, 268 Is controlled so that the rotational peripheral speeds of the piston drive motors 260 and 274 are intermittently driven at a constant speed so that the constant speed is equal to or higher than the maximum rotational peripheral speed of the plate cylinder 212.

  It should be noted that the rotational peripheral speeds of the piston drive motors 260 and 274 may be changed according to the rotational peripheral speed of the plate cylinder 212. , The moving speed of the pistons 254 and 268 is decelerated, and the jet pressure of air from the openings 210c and 211c decreases, so that good printing may not be performed. In such a case, it is necessary to increase the rotational peripheral speeds of the piston drive motors 260 and 274 as appropriate so as to keep the air ejection pressure from the openings 210c and 211c above a certain value.

  In the present embodiment, the first piston 254 is reciprocated by the first piston drive motor 260 and the second piston 268 is reciprocated by the second piston drive motor 274, but the piston drive motors 260 and 274 are not used. A configuration may be adopted in which a rotational driving force from a plate cylinder driving unit (not shown) is transmitted by a driving force transmission unit such as a gear or a belt to reciprocate the pistons 254 and 268.

  FIG. 18 shows a block diagram of the control means used in the eighth embodiment of the present invention. The eighth embodiment is different from the seventh embodiment only in that the control unit 282 controls the operation of the stencil printing apparatus 201 based on the paper size detection signal from the paper size detection sensor 234. Other configurations are the same.

  In the stencil printing apparatus 201 shown in the present embodiment, the timing at which the air is ejected from the opening 210c is a sheet feeding unit for the first plate-making image of the divided plate-making master 221 wound on the plate cylinder 212 during double-sided printing. After the paper P fed from 204 is pressed by the press roller 213, the front end portion of the paper P that has become the surface-printed paper PA when being peeled from the plate cylinder 212 by the first peeling member 210 is the opening 210c. Occupying a position corresponding to, and during double-sided printing, the paper P is a large size (in this embodiment, a paper transport direction length equal to or larger than A4 side (when the paper short direction is the paper transport direction)) Is used when approximately the middle of the length of the surface-printed paper PA in the paper conveyance direction occupies a position corresponding to the opening 210c.

  Accordingly, when a small size paper is used as the paper P during double-sided printing, the first piston drive motor 260 rotates the first rotating plate 256 one time while the plate cylinder 212 makes one rotation, and the first piston 254. Is reciprocated once in the first cylinder 253, and when a large-size sheet is used as the sheet P during double-sided printing, the first rotating plate 256 is rotated twice while the plate cylinder 212 is rotated once, so that the first The piston 254 is reciprocated twice in the first cylinder 253.

  Further, in the stencil printing apparatus 201 shown in the present embodiment, the timing at which air is ejected from the opening 211c is fed to the third plate-making image of the plate-making master 221 wound on the plate cylinder 212 during single-side printing. After the paper P fed from the section 204 is pressed by the press roller 213, the leading edge of the paper P that has become the printed paper PB when being peeled from the plate cylinder 212 by the second peeling member 211 is the opening 211c. When a corresponding position is occupied, and when a large-size sheet is used as the sheet P during single-sided printing, the middle of the length in the sheet transport direction of the printed sheet PB occupied the position corresponding to the opening 211c. Surface printing that is fed from the refeeding means 209 to the second plate-making image of the divided plate-making master 221 wound on the plate cylinder 212 during double-sided printing After the sheet paper PA is pressed by the press roller 213, the front end portion of the surface-printed paper PA that has become the printed paper PB when peeled from the plate cylinder 212 by the second peeling member 211 corresponds to the opening 211c. When the position is occupied, and when a large-size sheet is used as the sheet P during double-sided printing, the middle of the length of the printed sheet PB in the sheet conveyance direction occupies a position corresponding to the opening 211c. It has been established.

  Therefore, the second piston drive motor 274 rotates the second rotating plate 270 once while the plate cylinder 212 rotates once when a small-size sheet is used as the sheet P during single-sided printing and double-sided printing. When the second piston 268 is reciprocated once in the second cylinder 267 and a large-size sheet is used as the sheet P during single-sided printing and double-sided printing, the second rotating plate is rotated while the plate cylinder 212 makes one rotation. The second piston 268 is reciprocated twice in the second cylinder 267 by rotating the 270 twice.

Based on the above configuration, the operation of the stencil printing apparatus 201 in the eighth embodiment will be described below. First, a case where single-sided printing is set on the operation panel 281 will be described.
The operator stacks the paper P to be used for printing on the paper feed tray 229, opens the pressure plate 242 and places a document to be printed on the contact glass 241, and then closes the pressure plate 242 again. Thereafter, the plate making conditions are set by various keys on the operation panel 281 and then the plate making start key is pressed.

  When the plate making start key is pressed, the control means 282 confirms the size of the paper P stacked on the paper feed tray 229 based on the paper size detection signal from the paper size detection sensor 234. When the paper P is a small size paper (in this embodiment, the length in the paper transport direction is less than A4 width), the single-sided printing operation program for the small size paper is used. When the paper P is the large size paper, Read a single-sided printing operation program for large size paper. The single-sided printing operation of the stencil printing apparatus 201 when using small-size paper is the same as the single-sided printing operation of the stencil printing apparatus 201 in the seventh embodiment described above, so a description thereof is omitted here and when large-size paper is used. Only the single-sided printing operation of the stencil printing apparatus 201 will be described.

  When the plate making start key is pressed, a document image reading operation is performed in the image reading unit 207, and in parallel with this, a plate discharging operation is performed in the plate discharging unit 205. When the plate removal operation is completed, the plate feeding operation is performed, and the pre-printed master 221 is wound on the outer peripheral surface of the plate cylinder 212. When the plate feeding operation is completed, one sheet P is pulled out from the sheet feeding tray 229, and the sheet P is temporarily stopped by the registration roller pair 233 and then fed toward the printing unit 202. At this time, the swinging means (not shown) sets the pressing range of the press roller 213 against the plate cylinder 212 to the first range.

  The fed paper P is pressed by the pre-printed master 221 wound around the outer peripheral surface of the plate cylinder 212 rotating at a low speed by the press roller 213, and printing is performed. The paper P on which the printed image is formed and becomes the printed paper PB is peeled off from the plate-making master 221 on the outer peripheral surface of the plate cylinder by the second peeling member 211 from the front end portion thereof. At the time of peeling, the second piston drive motor 274 is operated, and the second piston 268 reciprocates twice in the second cylinder 267, whereby air is jetted twice from the opening 211c, and printed paper PB from the outer peripheral surface of the plate cylinder Is peeled well.

  The operation of the second piston drive motor 274 is performed when the leading end of the printed paper PB reaches a position corresponding to the opening 211c with reference to a plate cylinder angle signal from a rotary encoder (not shown) and when the printed paper PB is conveyed. The control means 282 controls the second rotary plate position detection sensor 278 to detect the dog 277 when the middle of the direction length reaches the position corresponding to the opening 211c. By the control of this control means 282, the middle of the length of the printed paper PB in the conveying direction between the front end of the printed paper PB and the master 221 on the outer peripheral surface of the plate cylinder and on the outer peripheral surface of the plate cylinder. Air is ejected from the opening 211c toward the master 221 having been made.

  The peeled printed paper PB falls downward and is received by the paper discharge transport member 239, and then transported and discharged onto the paper discharge tray 240. Thereafter, the plate cylinder 212 is rotated again to the home position and stopped. After the plate making operation is completed, the stencil printing apparatus 201 enters a single-sided printing standby state.

  When the trial printing key on the operation panel 281 is pressed after the stencil printing apparatus 201 enters the single-sided printing standby state, the plate cylinder 212 is driven to rotate at a peripheral speed corresponding to the set printing speed and the paper feeding unit When only one sheet P is fed from 204 and trial printing is performed, and the print start key is pressed, the plate cylinder 212 is driven to rotate at a peripheral speed corresponding to the set printing speed and the paper feeding unit 204 is driven. The sheet P is continuously fed from one side and a single-sided printing operation is performed. During the trial printing and the single-sided printing operation, air is sent from the second air supply means 266 when the printed paper PB is peeled from the outer peripheral surface of the plate cylinder, and the printed paper PB is peeled off. Is done well.

Next, a case where duplex printing is set on the operation panel 281 will be described.
The operator sets the paper P on the paper feed tray 229 and the original on the contact glass 241 as in the case of single-sided printing, sets the platemaking conditions using various keys on the operation panel 281, and then presses the platemaking start key.

  When the plate making start key is pressed, the control means 282 confirms the size of the paper P stacked on the paper feed tray 229 based on the paper size detection signal from the paper size detection sensor 234. Then, when the paper P is a small size paper, a double-sided printing operation program for small size paper is read, and when the paper P is a large size paper, a double-sided printing operation program for large size paper is read. Since the double-sided printing operation of the stencil printing apparatus 201 when using small-size paper is the same as the double-sided printing operation of the stencil printing apparatus 201 in the seventh embodiment described above, description thereof is omitted here, and when large-size paper is used. Only the double-sided printing operation of the stencil printing apparatus 201 will be described.

  When the plate making start key is pressed, a document image reading operation is performed in the image reading unit 207, and in parallel with this, a plate discharging operation is performed in the plate discharging unit 205. When the plate removal operation is completed, the plate feeding operation is performed, and the divided plate-making master 221 is wound on the outer peripheral surface of the plate cylinder 212. When the plate feeding operation is completed, one sheet P is pulled out from the sheet feeding tray 229, and the sheet P is temporarily stopped by the registration roller pair 233 and then fed toward the printing unit 202. At this time, the swinging means (not shown) sets the pressing range of the press roller 213 against the plate cylinder 212 to the second range, and the first peeling member 210 occupies the close position when the clamper passes the corresponding position.

  The fed paper P is pressed against the first plate-making image of the divided plate-making master 221 wound around the outer peripheral surface of the plate cylinder 212 rotating at a low speed by the press roller 213. The paper P, which has been formed with a surface image on one side and becomes a surface-printed paper PA, is peeled off from the divided plate-making master 221 on the outer peripheral surface of the plate cylinder by the first peeling member 210. At the time of peeling, the first piston drive motor 260 is operated, and the first piston 254 reciprocates twice in the first cylinder 253, whereby air is jetted twice from the opening 210c, and the surface printed paper from the outer peripheral surface of the plate cylinder The PA is peeled well.

  The operation of the first piston drive motor 260 is performed when the front end portion of the surface-printed paper PA reaches a position corresponding to the opening 210c with reference to a plate cylinder angle signal from a rotary encoder (not shown) and on the surface-printed paper PA. The control unit 282 controls the first rotary plate position detection sensor 264 to detect the dog 263 when the middle in the transport direction reaches a position corresponding to the opening 210c. By the control of the control means 282, the middle of the length in the transport direction of the surface-printed paper PA between the front end portion of the surface-printed paper PA and the divided plate-making master 221 on the outer circumference of the plate cylinder and the outer circumference of the plate cylinder are controlled. Air is ejected from the opening 210c toward the divided master-making master 221 on the surface. The peeled surface-printed paper PA is dropped downward and placed on the auxiliary tray 208, and is then transported by the re-feed transport member 218 and the other end is in contact with the re-feed positioning member 219. It is temporarily stopped at.

  The plate cylinder 212 continues to rotate. During this time, the first peeling member 210 is displaced from the close position to the separated position, and the swinging means (not shown) reduces the pressing range of the press roller 213 against the plate cylinder 212 in the third range. Switch to range. Then, the paper re-feeding registration roller 217 is swung at the same predetermined timing as in the seventh embodiment, and the surface-printed paper PA is pressed against the peripheral surface of the press roller 213. The surface-printed paper PA is conveyed toward the contact portion between the plate cylinder 212 and the press roller 213 by the rotational force of the press roller 213.

  The conveyed surface-printed paper PA is pressed against the second plate-making image of the divided plate-making master 221 wound around the outer peripheral surface of the plate cylinder 212 rotating at a low speed by the press roller 213. The front-side printed paper PA that has been formed with the back-side image on the other side and becomes the printed paper PB is peeled off from the divided plate-making master 221 on the outer peripheral surface of the plate cylinder by the second peeling member 211. At the time of peeling, the second piston drive motor 274 is operated, and the second piston 268 reciprocates twice in the second cylinder 267, whereby air is jetted twice from the opening 211c, and printed paper PB from the outer peripheral surface of the plate cylinder Is peeled well.

  The operation of the second piston drive motor 274 is performed when the leading end of the printed paper PB reaches a position corresponding to the opening 211c on the basis of a plate cylinder angle signal from a rotary encoder (not shown) and the transport direction of the printed paper PB. The control means 282 controls the second rotary plate position detection sensor 278 to detect the dog 277 when the middle of the length reaches the position corresponding to the opening 211c. Under the control of the control means 282, the middle of the length of the printed paper PB in the conveyance direction between the front end of the printed paper PB and the divided master-making master 221 on the outer peripheral surface of the plate cylinder and on the outer periphery of the plate cylinder. The air is ejected from the opening 211c toward the divided master-making master 221.

  The peeled printed paper PB falls downward and is received by the paper discharge transport member 239, and then transported and discharged onto the paper discharge tray 240. Thereafter, the plate cylinder 212 is rotated again to the home position and stopped. After the plate making operation is finished, the stencil printing apparatus 201 enters a duplex printing standby state.

  After the stencil printing apparatus 201 enters the duplex printing standby state, when a trial printing key is pressed after inputting printing conditions using various keys on the operation panel 281, the plate cylinder is rotated at a peripheral speed corresponding to the set printing speed. 212 is rotated and only one sheet P is fed from the sheet feeding unit 204 to perform a test printing. This test printing is performed in the same manner as the plate-printing operation except that the rotational peripheral speed of the plate cylinder 212 is different. Even during the trial printing, air is sent twice from the first air supply means 252 when the front-side printed paper PA is peeled off, and from the second air supply means 266 when the printed paper PB is peeled off in the same manner as at the time of printing. The surface-printed paper PA and the printed paper PB are favorably peeled from the outer peripheral surface of the plate cylinder. Then, after the peeled printed paper PB is discharged onto the paper discharge tray 240, the plate cylinder 212 stops at the home position, so that the trial printing operation is finished and the stencil printing apparatus 201 enters the duplex printing standby state again. .

  When the position or density of the image is confirmed by trial printing and the print start key is pressed after the number of prints is input on the operation panel 281, a printing operation is performed. This printing operation is different from the printing operation described in the seventh embodiment only in that air is sent once or twice from each air supply means 252 and 266 in the same manner as when printing. Other operations are the same.

  According to the configuration described above, during single-sided printing when using a large-size sheet, the large size is removed from the second peeling member 211 at a position corresponding to the leading end of the sheet and a position corresponding to approximately the middle of the length in the conveyance direction of the sheet P. At the time of double-sided printing during use of paper, air is ejected from the first peeling member 210 at the same position as described above during the front surface printing and from the second peeling member 211 at the same position as described above during backside printing. In addition, the same effects as those of the embodiment can be obtained, and even when the paper P has a solid image portion extending substantially rearwardly from the central portion of the paper P in the paper conveyance direction, the adhesion of the ink can be achieved. The paper P attached to the divided plate-making master 221 on the outer peripheral surface of the plate cylinder can be peeled off by force, and there is a problem that nail mark stains occur on the paper P. To prevent the occurrence of a problem that the sheet P is thereby cause paper jam stuck to each stripping member 210 and 211 can be obtained good prints.

  In the present embodiment, the second piston 268 makes one reciprocation within the second cylinder 267 during one rotation of the plate cylinder 212 during single-sided printing when using small-size paper, and 1 of the plate cylinder 212 during double-sided printing when using small-size paper. During rotation, the first piston 254 reciprocates once in the first cylinder 253 and the second piston 268 reciprocates once in the second cylinder 267. During one-side printing when using large-size paper, the first piston 254 revolves during one rotation of the plate cylinder 212. The two pistons 268 make two reciprocations in the second cylinder 267, and during double-sided printing when using large-size paper, the first piston 254 makes two reciprocations in the first cylinder 253 during one rotation of the plate cylinder 212 and the second piston 268 A configuration in which the second cylinder 267 is reciprocated twice is adopted.

  Here, since the rotational peripheral speed of the plate cylinder 212 can be changed according to the printing speed, the time during which the plate cylinder 212 makes one rotation also changes according to the printing speed. For this reason, in this embodiment, the rotational peripheral speeds of the piston drive motors 260 and 274 are such that the reciprocating speed of the pistons 254 and 268 is a constant speed that is twice or more the maximum rotational peripheral speed of the plate cylinder 212. Is controlled to rotate intermittently at a constant speed.

  It should be noted that the rotational peripheral speeds of the piston drive motors 260 and 274 may be changed according to the rotational peripheral speed of the plate cylinder 212. In this case, the moving speed of the pistons 254 and 268 is also reduced, and the jet pressure of air from the openings 210c and 211c may be reduced to prevent good printing. In such a case, it is necessary to increase the rotational peripheral speeds of the piston drive motors 260 and 274 as appropriate so as to keep the air ejection pressure from the openings 210c and 211c above a certain value.

  Next, a ninth embodiment of the present invention will be described. Compared with the eighth embodiment described above, the ninth embodiment replaces the first air supply means 252 with the first air supply means 283, and replaces the second air supply means 266 with the second air supply means. The only difference is that 311 is used, and the other configurations are the same.

  FIG. 19 shows the first air supply means 283 used in the ninth embodiment of the present invention. The first air supply means 283 includes a first cylinder 284, a first piston 285 that can reciprocate inside the first cylinder 284, one end connected to the air discharge port 284a of the first cylinder 284, and the other end connected to a first peeling member. An air hose 287 connected to a Y-shaped joint 286 attached to one end of 210, a first rotating plate 288, a first link having one end attached to the periphery of the first rotating plate 288 and the other end attached to the first piston 285 289, a third cylinder 290, a third piston 291 that can reciprocate inside the third cylinder 290, an air hose 292 that has one end connected to the air outlet 290a of the third cylinder 290 and the other end connected to a Y-shaped joint 286. A third rotating plate 293, one end attached to the periphery of the third rotating plate 293 and the other end attached to the third piston 291. It is mainly composed of a click 294, and the like.

  The cylinders 284 and 290 are supported by the apparatus main body, the first rotating plate 288 is supported by a support shaft 295 rotatably supported by the apparatus main body, and the third rotating plate 293 is rotatably supported by the apparatus main body. Each is attached to a support shaft 296. As shown in FIG. 20, a timing pulley 297 is attached to the support shaft 295, and a timing pulley 298 is attached to the support shaft 296. The timing pulley 297 is a first piston drive motor 299 as a drive motor that is a stepping motor. The timing pulley 298 is driven and connected by a pinion 303 fixed to the output shaft of a third piston drive motor 302 as a stepping motor and a timing belt 304 by a pinion 300 fixed to the output shaft of the motor and a timing belt 301. Has been.

  A dog 305 is attached to the peripheral edge of the first rotary plate 288, and a dog 306 is attached to the peripheral edge of the third rotary plate 293. The dogs 305 and 306 detect the first rotary plate position as rotating plate position detecting means. It is detected by the sensor 307 and the third rotary plate position detection sensor 308, respectively. The arrangement positions of the dogs 305 and 306 and the rotary plate position detection sensors 307 and 308 are the same as the positional relationship between the dog 263 and the first rotary plate position detection sensor 264 in the seventh embodiment.

  The first rotary plate 288, the first link 289, the support shaft 295, the timing pulley 297, the first piston drive motor 299, the pinion 300, the timing belt 301, the first piston drive means 309, the third rotary plate 293, The third link 294, the support shaft 296, the timing pulley 298, the third piston drive motor 302, the pinion 303, and the timing belt 304 constitute the third piston drive means 310, respectively.

  FIG. 21 shows the second air supply means 311 used in the ninth embodiment of the present invention. The second air supply means 311 includes a second cylinder 312, a second piston 313 that can reciprocate inside the second cylinder 312, one end connected to the air discharge port 312 a of the second cylinder 312, and the other end to a second peeling member. An air hose 315 connected to a Y-shaped joint 314 attached to one end of 211, a second rotating plate 316, a second link having one end attached to the periphery of the second rotating plate 316 and the other end attached to the second piston 313. 317, a fourth cylinder 318, a fourth piston 319 capable of reciprocating inside the fourth cylinder 318, an air hose 320 having one end connected to the air outlet 318a of the fourth cylinder 318 and the other end connected to the Y-shaped joint 314. A fourth rotary plate 321, one end attached to the periphery of the fourth rotary plate 321 and the other end attached to the fourth piston 319. It is mainly composed of click 322 and the like.

  The cylinders 312 and 318 are respectively supported by the apparatus main body, the second rotating plate 316 is supported by a support shaft 323 rotatably supported by the apparatus main body, and the fourth rotating plate 321 is rotatably supported by the apparatus main body. Each is attached to a support shaft 324. As shown in FIG. 22, a timing pulley 325 is attached to the support shaft 323, and a timing pulley 326 is attached to the support shaft 324. The timing pulley 325 is a second piston drive motor 327 as a drive motor that is a stepping motor. The timing pulley 326 is driven and connected by a pinion 331 fixed to the output shaft of the fourth piston drive motor 330 as a stepping motor and a timing belt 332 by a pinion 328 fixed to the output shaft and a timing belt 329, respectively. Has been.

  A dog 333 is attached to the periphery of the second rotating plate 316, and a dog 334 is attached to the periphery of the fourth rotating plate 321, and each of the dogs 333 and 334 detects the second rotating plate position as a rotating plate position detecting means. It is detected by the sensor 335 and the fourth rotary plate position detection sensor 336, respectively. The arrangement positions of the dogs 333 and 334 and the rotary plate position detection sensors 335 and 336 are the same as the positional relationship between the dog 277 and the second rotary plate position detection sensor 278 in the seventh embodiment.

  The second piston plate 316, the second link 317, the support shaft 323, the timing pulley 325, the second piston drive motor 327, the pinion 328, and the timing belt 329 make the second piston drive means 337, and the fourth rotary plate 321, The fourth link 322, the support shaft 324, the timing pulley 326, the fourth piston drive motor 330, the pinion 331, and the timing belt 332 constitute the fourth piston drive means 338, respectively.

  Based on the above configuration, the operation of the stencil printing apparatus 201 in the ninth embodiment will be described below. First, a case where single-sided printing is set on the operation panel 281 and a small size paper P is placed on the paper feed tray 229 will be described.

  When the plate making start key is pressed by the operator, the control means 282 confirms the size of the paper P loaded on the paper feed tray 229 based on the signal from the paper size detection sensor 234, and the single side for small size paper. Read the printing operation program. In this case, the ejection of air from the second peeling member 211 to the paper P is performed only at a position corresponding to the front end of the paper.

  When the plate making start key is pressed, the image reading operation and the plate discharging operation are performed as in the eighth embodiment, and the plate making operation and the plate feeding operation are performed after the stencil printing apparatus 201 enters the plate feeding standby state. When the plate feeding operation is completed, one sheet P is pulled out from the sheet feeding tray 229, and the sheet P is temporarily stopped by the registration roller pair 233 and then fed toward the printing unit 202.

  The fed paper P is pressed by the pre-printed master 221 wound around the outer peripheral surface of the plate cylinder 212 rotating at a low speed by the press roller 213, and printing is performed. The paper P on which the printed image is formed and becomes the printed paper PB is peeled off from the plate-making master 221 on the outer peripheral surface of the plate cylinder by the second peeling member 211 from the front end portion thereof. At the time of separation, either the second piston drive motor 327 or the fourth piston drive motor 330 is operated, and either the second piston 313 or the fourth piston 319 reciprocates in the corresponding cylinder to open the opening. Air is ejected from 211c, and the printed paper PB is peeled favorably from the outer peripheral surface of the plate cylinder.

  The operations of the second piston drive motor 327 and the fourth piston drive motor 330 are performed when the leading end of the printed paper PB reaches a position corresponding to the opening 211c with reference to a plate cylinder angle signal from a rotary encoder (not shown). The control unit 282 controls the second rotary plate position detection sensor 335 to detect the dog 333 and the fourth rotary plate position detection sensor 336 to detect the dog 334, respectively. Under the control of the control means 282, air is ejected from the opening 211c between the leading end portion of the printed paper PB and the master-making master 221 on the outer peripheral surface of the plate cylinder.

  The peeled printed paper PB falls downward and is received by the paper discharge transport member 239, and then transported and discharged onto the paper discharge tray 240. Thereafter, the plate cylinder 212 is rotated again to the home position and stopped. After the plate making operation is completed, the stencil printing apparatus 201 enters a single-sided printing standby state.

  When the trial printing key on the operation panel 281 is pressed after the stencil printing apparatus 201 enters the single-sided printing standby state, the plate cylinder 212 is driven to rotate at a peripheral speed corresponding to the set printing speed and the paper feeding unit When only one sheet P is fed from 204 and trial printing is performed, and the print start key is pressed, the plate cylinder 212 is driven to rotate at a peripheral speed corresponding to the set printing speed and the paper feeding unit 204 is driven. The sheet P is continuously fed from one side and a single-sided printing operation is performed. Even during the trial printing and the single-sided printing operation, air is sent from the second air supply means 311 when the printed paper PB is peeled off from the outer peripheral surface of the plate cylinder in the same manner as at the time of printing. Peeling is performed well.

Next, a case where single-sided printing is set on the operation panel 281 and a large size paper P is placed on the paper feed tray 229 will be described.
When the plate making start key is pressed by the operator, the control means 282 confirms the size of the paper P loaded on the paper feed tray 229 based on a signal from the paper size detection sensor 234, and single-sided for large size paper. Read the printing operation program. In this case, the ejection of air to the paper P from the second peeling member 211 is performed at a position corresponding to the front end of the paper and a position corresponding to approximately the middle of the length in the paper transport direction.

  When the plate making start key is pressed, the image reading operation and the plate discharging operation are performed in the same manner as described above, and the plate making operation and the plate feeding operation are performed after the stencil printing apparatus 201 enters the plate feeding standby state. When the plate feeding operation is completed, one sheet P is pulled out from the sheet feeding tray 229, and the sheet P is temporarily stopped by the registration roller pair 233 and then fed toward the printing unit 202.

  The fed paper P is pressed by the pre-printed master 221 wound around the outer peripheral surface of the plate cylinder 212 rotating at a low speed by the press roller 213, and printing is performed. The paper P on which the printed image is formed and becomes the printed paper PB is peeled off from the plate-making master 221 on the outer peripheral surface of the plate cylinder by the second peeling member 211 from the front end portion thereof. At the time of separation, the second piston drive motor 327 and the fourth piston drive motor 330 are operated, respectively, and the second piston 313 and the fourth piston 319 reciprocate in the corresponding cylinders, respectively, so that air flows twice from the opening 211c. The printed paper PB is ejected favorably from the outer peripheral surface of the plate cylinder.

  The operations of the second piston drive motor 327 and the fourth piston drive motor 330 are performed when the leading end of the printed paper PB reaches a position corresponding to the opening 211c with reference to a plate cylinder angle signal from a rotary encoder (not shown). The fourth rotation is performed when the second rotation plate position detection sensor 335 detects the dog 333 and when the middle of the length of the printed sheet PB in the sheet conveyance direction reaches a position corresponding to the opening 211c. The plate position detection sensor 336 is controlled by the control means 282 so that the timing for detecting the dog 334 is reached. Under the control of the control means 282, the middle of the length of the printed paper PB in the paper conveyance direction between the front end of the printed paper PB and the master 221 on the outer peripheral surface of the plate cylinder and on the outer peripheral surface of the plate cylinder. The air is jetted from the opening 211c toward the master 221 having been made.

  The peeled printed paper PB falls downward and is received by the paper discharge transport member 239, and then transported and discharged onto the paper discharge tray 240. Thereafter, the plate cylinder 212 is rotated again to the home position and stopped. After the plate making operation is completed, the stencil printing apparatus 201 enters a single-sided printing standby state.

  When the trial printing key on the operation panel 281 is pressed after the stencil printing apparatus 201 enters the single-sided printing standby state, the plate cylinder 212 is driven to rotate at a peripheral speed corresponding to the set printing speed and the paper feeding unit When only one sheet P is fed from 204 and trial printing is performed, and the print start key is pressed, the plate cylinder 212 is driven to rotate at a peripheral speed corresponding to the set printing speed and the paper feeding unit 204 is driven. The sheet P is continuously fed from one side and a single-sided printing operation is performed. Even during the trial printing and the single-sided printing operation, air is sent from the second air supply means 311 when the printed paper PB is peeled off from the outer peripheral surface of the plate cylinder in the same manner as at the time of printing. Peeling is performed well.

Next, a case where duplex printing is set on the operation panel 281 and a small-sized sheet P is placed on the sheet feeding tray 229 will be described.
When the plate making start key is pressed by the operator, the control means 282 confirms the size of the paper P loaded on the paper feed tray 229 based on the signal from the paper size detection sensor 234, and double-sided for small size paper. Read the printing operation program. In this case, the ejection of air to the paper P from the first peeling member 210 and the second peeling member 211 is performed only at a position corresponding to the leading edge of the paper.

  When the plate making start key is pressed, the image reading operation and the plate discharging operation are performed in the same manner as described above, and the plate making operation and the plate feeding operation are performed after the stencil printing apparatus 201 enters the plate feeding standby state. When the plate feeding operation is completed, one sheet P is pulled out from the sheet feeding tray 229, and the sheet P is temporarily stopped by the registration roller pair 233 and then fed toward the printing unit 202.

  The fed paper P is pressed by the divided plate-making master 221 wound around the outer peripheral surface of the plate cylinder 212 rotating at a low speed by the press roller 213, and the first plate-making image is printed. The paper P that has been formed with the front surface printed image to become the front surface printed paper PA is peeled from the front end of the divided plate-making master 221 on the outer peripheral surface of the plate cylinder by the first peeling member 210. At the time of separation, either the first piston drive motor 299 or the third piston drive motor 302 operates, and either the first piston 285 or the third piston 291 reciprocates in the corresponding cylinder to open the opening. Air is jetted from 210c, and the surface-printed paper PA is peeled well from the outer peripheral surface of the plate cylinder.

  The operations of the first piston drive motor 299 and the third piston drive motor 302 are performed when the front end of the surface-printed paper PA reaches a position corresponding to the opening 210c with reference to a plate cylinder angle signal from a rotary encoder (not shown). Further, the control means 282 controls the first rotary plate position detection sensor 307 and the third rotary plate position detection sensor 308 so as to detect the dog 305 and the dog 306, respectively. Under the control of the control means 282, air is ejected from the opening 210c between the front end of the surface-printed paper PA and the divided plate-making master 221 on the outer periphery of the plate cylinder.

  The peeled surface-printed paper PA is dropped downward and placed on the auxiliary tray 208, and is then transported by the re-feed transport member 218 and the other end is in contact with the re-feed positioning member 219. It is temporarily stopped at. Thereafter, the re-feeding registration roller 217 is swung at the same timing as in the seventh embodiment, so that the surface-printed paper PA is brought into contact with the plate cylinder 212 and the press roller 213 by the rotational force of the press roller 213. It is conveyed toward.

  The conveyed surface-printed paper PA is pressed by the divided plate-making master 221 wound around the outer peripheral surface of the plate cylinder 212 rotating at a low speed by the press roller 213, and the printing of the second plate-making image is performed. The front-side printed paper PA that has been formed with the back-side printed image and becomes the printed paper PB is peeled from the front end of the divided plate-making master 221 on the outer peripheral surface of the plate cylinder by the second peeling member 211. At the time of separation, either the second piston drive motor 327 or the fourth piston drive motor 330 is operated, and either the second piston 313 or the fourth piston 319 reciprocates in the corresponding cylinder to open the opening. Air is ejected from 211c, and the printed paper PB is peeled favorably from the outer peripheral surface of the plate cylinder.

  The operations of the second piston drive motor 327 and the fourth piston drive motor 330 are performed when the leading end of the printed paper PB reaches a position corresponding to the opening 211c with reference to a plate cylinder angle signal from a rotary encoder (not shown). The control unit 282 controls the second rotary plate position detection sensor 335 to detect the dog 333 and the fourth rotary plate position detection sensor 336 to detect the dog 334, respectively. Under the control of the control means 282, air is ejected from the opening 211c between the leading end of the printed paper PB and the divided master-making master 221 on the outer peripheral surface of the plate cylinder.

  The peeled printed paper PB falls downward and is received by the paper discharge transport member 239, and then transported and discharged onto the paper discharge tray 240. Thereafter, the plate cylinder 212 is rotated again to the home position and stopped. After the plate making operation is finished, the stencil printing apparatus 201 enters a duplex printing standby state.

  When the trial printing key on the operation panel 281 is pressed after the stencil printing apparatus 201 enters the duplex printing standby state, the plate cylinder 212 is driven to rotate at a peripheral speed corresponding to the set printing speed and the paper feeding unit When only one sheet P is fed from 204 and trial printing is performed, and the print start key is pressed, the plate cylinder 212 is driven to rotate at a peripheral speed corresponding to the set printing speed and the paper feeding unit 204 is driven. The sheet P is continuously fed from the beginning and the duplex printing operation is performed. The trial printing is performed in the same manner as the above-described printing operation except that the rotational peripheral speed of the plate cylinder 212 is different. In the double-sided printing operation, air is sent from the air supply units 283 and 311 in the same manner as the printing operation. Except for, the double-sided printing operation described in the seventh embodiment is performed.

Next, a case where duplex printing is set on the operation panel 281 and a large size paper P is placed on the paper feed tray 229 will be described.
When the plate making start key is pressed by the operator, the control means 282 confirms the size of the paper P loaded on the paper feed tray 229 based on the signal from the paper size detection sensor 234, and double-sided for large size paper. Read the printing operation program. In this case, the ejection of air to the paper P from the first peeling member 210 and the second peeling member 211 is performed at a position corresponding to the front end of the paper and a position corresponding to approximately the middle of the length in the paper transport direction.

  When the plate making start key is pressed, the image reading operation and the plate discharging operation are performed in the same manner as described above, and the plate making operation and the plate feeding operation are performed after the stencil printing apparatus 201 enters the plate feeding standby state. When the plate feeding operation is completed, one sheet P is pulled out from the sheet feeding tray 229, and the sheet P is temporarily stopped by the registration roller pair 233 and then fed toward the printing unit 202.

  The fed paper P is pressed by the divided plate-making master 221 wound around the outer peripheral surface of the plate cylinder 212 rotating at a low speed by the press roller 213, and the first plate-making image is printed. The paper P that has been formed with the front surface printed image to become the front surface printed paper PA is peeled from the front end of the divided plate-making master 221 on the outer peripheral surface of the plate cylinder by the first peeling member 210. At the time of separation, the first piston drive motor 299 and the third piston drive motor 302 are operated, respectively, and the first piston 285 and the third piston 291 reciprocate in the corresponding cylinders, respectively, so that air flows twice from the opening 210c. The surface-printed paper PA is ejected well from the outer periphery of the plate cylinder.

  The operations of the first piston drive motor 299 and the third piston drive motor 302 are performed when the front end of the surface-printed paper PA reaches a position corresponding to the opening 210c with reference to a plate cylinder angle signal from a rotary encoder (not shown). The first rotation plate position detection sensor 307 detects the dog 305, and when the middle of the length of the surface-printed paper PA in the paper conveyance direction reaches a position corresponding to the opening 210c. The three-rotation plate position detection sensor 308 is controlled by the control means 282 so that the timing for detecting the dog 306 is reached. Under the control of the control means 282, the middle of the length of the surface-printed paper PA in the paper conveyance direction between the front end portion of the surface-printed paper PA and the divided plate-making master 221 on the outer peripheral surface of the plate cylinder and the plate cylinder are controlled. Air is ejected from the opening 210c between the master 221 on the outer peripheral surface.

  The peeled surface-printed paper PA is dropped downward and placed on the auxiliary tray 208, and is then transported by the re-feed transport member 218 and the other end is in contact with the re-feed positioning member 219. It is temporarily stopped at. Thereafter, the re-feeding registration roller 217 is swung at the same timing as in the seventh embodiment, so that the surface-printed paper PA is brought into contact with the plate cylinder 212 and the press roller 213 by the rotational force of the press roller 213. It is conveyed toward.

  The conveyed surface-printed paper PA is pressed by the divided plate-making master 221 wound around the outer peripheral surface of the plate cylinder 212 rotating at a low speed by the press roller 213, and the printing of the second plate-making image is performed. The front-side printed paper PA that has been formed with the back-side printed image and becomes the printed paper PB is peeled from the front end of the divided plate-making master 221 on the outer peripheral surface of the plate cylinder by the second peeling member 211. At the time of separation, the second piston drive motor 327 and the fourth piston drive motor 330 are operated, respectively, and the second piston 313 and the fourth piston 319 reciprocate in the corresponding cylinders, respectively, so that air flows twice from the opening 211c. The printed paper PB is ejected favorably from the outer peripheral surface of the plate cylinder.

  The operations of the second piston drive motor 327 and the fourth piston drive motor 330 are performed when the leading end of the printed paper PB reaches a position corresponding to the opening 211c with reference to a plate cylinder angle signal from a rotary encoder (not shown). The fourth rotation is performed when the second rotation plate position detection sensor 335 detects the dog 333 and when the middle of the length of the printed sheet PB in the sheet conveyance direction reaches a position corresponding to the opening 211c. The plate position detection sensor 336 is controlled by the control means 282 so that the timing for detecting the dog 334 is reached. Under the control of the control means 282, the middle of the length of the printed sheet PB in the sheet conveying direction between the leading end of the printed sheet PB and the divided plate-making master 221 on the outer surface of the plate cylinder and the outer surface of the plate cylinder Air is ejected from the opening 211c toward the upper master 221 that has been divided into the plate-making processes. The peeled printed paper PB falls downward and is received by the paper discharge transport member 239, and then transported and discharged onto the paper discharge tray 240. Thereafter, the plate cylinder 212 is rotated again to the home position and stopped. After the plate making operation is finished, the stencil printing apparatus 201 enters a duplex printing standby state.

  When the trial printing key on the operation panel 281 is pressed after the stencil printing apparatus 201 enters the duplex printing standby state, the plate cylinder 212 is driven to rotate at a peripheral speed corresponding to the set printing speed and the paper feeding unit When only one sheet P is fed from 204 and trial printing is performed, and the print start key is pressed, the plate cylinder 212 is driven to rotate at a peripheral speed corresponding to the set printing speed and the paper feeding unit 204 is driven. The sheet P is continuously fed from the beginning and the duplex printing operation is performed. The test printing is performed in the same manner as the above-described plate-fixing operation except that the rotational peripheral speed of the plate cylinder 212 is different, and the double-sided printing operation is performed twice from each air supply means 283, 311 in the same manner as during plate-printing. Is performed in the same manner as the double-sided printing operation described in the seventh embodiment except that is sent.

  In the above embodiment, the fourth rotary plate position detection sensor 336 is the dog 334 when the leading end of the printed paper PB reaches the position corresponding to the opening 211c during single-sided printing and double-sided printing when using large size paper. The second rotary plate position detection sensor 335 detects the dog 333 when the middle of the length of the printed paper PB in the paper conveyance direction reaches a position corresponding to the opening 211c. It is good also as a structure which the control means 282 controls each piston drive motor 327,330 so that it may become a timing.

  In the above embodiment, the third rotary plate position detection sensor 308 detects the dog 306 when the front end of the surface-printed paper PA reaches a position corresponding to the opening 210c during double-sided printing when using large-size paper. And the timing at which the first rotary plate position detection sensor 307 detects the dog 305 when the middle of the length in the sheet conveyance direction of the surface-printed sheet PA reaches a position corresponding to the opening 210c. As such, the control means 282 may control each piston drive motor 299, 302.

  Also in the present embodiment, as in the eighth embodiment, the paper corresponds to the leading end of the paper during single-sided printing and double-sided printing using small-size paper, and the paper during single-sided printing and double-sided printing using large-size paper. Since air is ejected from each of the peeling members 210 and 211 at a position corresponding to approximately the middle of the length in the conveyance direction of the leading end and the paper, the same operational effects as in the eighth embodiment can be obtained.

  In this embodiment, during single-sided printing when using small-size paper, during one rotation of the plate cylinder 212, one of the pistons 313 and 319 makes one reciprocation within the corresponding cylinders 312 and 318, and when using small-size paper. During double-sided printing, one of the pistons 285 and 291 reciprocates once within the corresponding cylinder 284 and 290 during one rotation of the plate cylinder 212 and one of the pistons 313 and 319 corresponds. When reciprocating within the cylinders 312 and 318, when single-sided printing is performed when large-size paper is used, each piston 313 and 319 is reciprocated once within the corresponding cylinder 312 and 318 during one rotation of the plate cylinder 212, and when large-size paper is used. During double-sided printing, the pistons 285, 291 pass through the corresponding cylinders 284, 290 during one rotation of the plate cylinder 212. Each piston 313,319 is employed each one reciprocation constituting the corresponding cylinder 312 and 318 together with respectively 1 reciprocates.

  Also in this embodiment, since the rotational peripheral speed of the plate cylinder 212 can be changed according to the printing speed, the time during which the plate cylinder 212 makes one revolution also changes according to the printing speed. For this reason, in this embodiment, the piston drive motors 299, 302, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, Control is performed so that the rotational circumferential speed of 330 is intermittently driven at a constant speed. It should be noted that the rotational peripheral speeds of the piston drive motors 299, 302, 327, and 330 may be changed according to the rotational peripheral speed of the plate cylinder 212. During the low-speed rotation, the moving speeds of the pistons 285, 291, 313 and 319 are also reduced, and the jet pressure of air from the openings 210c and 211c may be reduced, and good printing may not be performed. In such a case, it is necessary to increase the rotational peripheral speeds of the piston drive motors 299, 302, 327, and 330 as appropriate, and to maintain the air ejection pressure from the openings 210c and 211c at a certain value or more.

  In the eighth and ninth embodiments described above, the first piston 254 is driven by the first piston drive motor 260, the second piston 268 is driven by the second piston drive motor 274, and the first piston 285 is driven by the first piston drive motor 299. The second piston 313 is reciprocated by the second piston drive motor 327, the third piston 291 is reciprocated by the third piston drive motor 302, and the fourth piston 319 is reciprocated by the fourth piston drive motor 330. Without using the drive motors 260, 274, 299, 327, 302, and 330, the rotational drive force from the plate cylinder drive means (not shown) is transmitted by drive force transmission means such as gears and belts, and the pistons 254, 268, 285, respectively. It is good also as a structure which reciprocates 313,291,319.

  When this configuration is adopted in the eighth embodiment, the second piston 268 is rotated during one rotation of the plate cylinder during single-sided printing when using small size paper, and the plate cylinder is rotating during two-sided printing when using small size paper. The first piston 254 and the second piston 268 are reciprocated once each, and when the large size paper is used, the second piston 268 is rotated during one-side printing when the large size paper is used, and when the double size printing is performed when the large size paper is used, the plate cylinder is rotated once. Since it is necessary to reciprocate the first piston 254 and the second piston 268 in each of them, the driving force transmitting means is a path and piston that transmits the rotational driving force for one rotation of the plate cylinder as the driving force for one reciprocation of the piston. It is necessary to configure two paths, a path for transmitting while increasing the driving force for two reciprocations and switching the driving force transmission path by the switching means. There is.

  In both the eighth and ninth embodiments, when large-size paper is used, it is necessary to eject air at a position approximately in the middle of the paper P conveyance direction. It is necessary to change the spout location. In this case, it is necessary to control the reciprocation of the pistons 254, 268, 285, 313, 291 and 319 by using connecting means such as a clutch for connecting or disconnecting the driving force as the driving force transmitting means.

  FIG. 23 shows a block diagram of the control means used in the tenth embodiment of the present invention. The control means 339 determines from the image data signal stored in the image memory 214 whether each original has a solid image portion, and in which portion the solid image portion exists using a predetermined threshold value. In addition, when a solid image portion exists, it has a function of detecting its position. The tenth embodiment is different from the seventh embodiment only in that the control means 339 controls the operation of the stencil printing apparatus 201 in accordance with the presence and position of a solid image portion. Are the same.

  In the stencil printing apparatus 201 shown in the present embodiment, the timing at which the air is ejected from the opening 210c is a sheet feeding unit for the first plate-making image of the divided plate-making master 221 wound on the plate cylinder 212 during double-sided printing. When the paper P fed from 204 is pressed by the press roller 213 and then peeled off from the plate cylinder 212 by the first peeling member 210, the leading end of the paper P that has become the surface printed paper PA is opened. When a position corresponding to 210c is occupied, and when there is a solid image portion in the first plate-making image of the divided plate-making master 221 at the time of double-sided printing, the solid image portion printed on the surface-printed paper PA is the opening 210c. It is determined when the corresponding position is occupied.

  Accordingly, the first piston driving motor 260 rotates the first rotating plate 256 once while the plate cylinder 212 rotates once when there is no solid image portion in the first plate-making image of the divided plate-making master 221 during double-sided printing. When the first piston 254 is reciprocated once in the first cylinder 253, and there is a solid image portion in the first plate-making image of the divided plate-making master 221 during double-sided printing, the plate cylinder 212 is rotated once. The first rotating plate 256 is rotated twice to reciprocate the first piston 254 twice in the first cylinder 253.

  Further, in the stencil printing apparatus 201 shown in the present embodiment, the timing at which air is ejected from the opening 211c is fed to the third plate-making image of the plate-making master 221 wound on the plate cylinder 212 during single-side printing. After the sheet P fed from the section 204 is pressed by the press roller 213, the leading end portion of the sheet P that has become the printed sheet PB when being peeled from the plate cylinder 212 by the second peeling member 211 is the opening 211c. The solid image portion printed on the printed paper PB when the solid image portion is present in the third plate-making image of the pre-printed master 221 at the time of single-sided printing. And the second plate-making image of the divided plate-making master 221 wound on the plate cylinder 212 at the time of double-sided printing is supplied from the re-feeding means 209. After the surface-printed paper PA that has been printed is pressed by the press roller 213, the front end portion of the surface-printed paper PA that has become the printed paper PB when the second peeling member 211 is peeled off from the plate cylinder 212 is opened. When a position corresponding to 211c is occupied, and when there is a solid image portion in the second plate-making image of the divided plate-making master 221 during duplex printing, the solid image portion printed on the printed paper PB corresponds to the opening 211c. It is determined when the position to occupy.

  Accordingly, the second piston drive motor 274 rotates the plate cylinder 212 once when there is no solid image portion in the second plate-making image of the plate-making master 221 at the time of single-side printing and the divided plate-making master 221 at the time of double-side printing. In the meantime, the second rotating plate 270 is rotated once to cause the second piston 268 to reciprocate once in the second cylinder 267, and the second plate-making image of the plate-making master 221 at the time of single-sided printing and the divided plate-making master 221 at the time of double-sided printing. When the solid image portion exists, the second rotating plate 270 is rotated twice while the plate cylinder 212 rotates once, and the second piston 268 is reciprocated twice in the second cylinder 267.

  If it is determined by the detection of the presence or absence of the solid image portion described above that there are two or more solid image portions in each of the plate making images of the master plate 221 and the divided plate making master 221, the air from the openings 210c and 211c. Is ejected only to the solid image portion located on the most downstream side in the sheet conveying direction.

  Based on the above configuration, the operation of the stencil printing apparatus 201 in the tenth embodiment will be described below. First, a case where single-sided printing is set on the operation panel 281 will be described.

  The operator opens the pressure plate 242, places a document to be printed on the contact glass 241, and then closes the pressure plate 242 again. Thereafter, the plate making conditions are set by various keys on the operation panel 281 and then the plate making start key is pressed. When the plate making start key is pressed, the image reading unit 207 performs a document image reading operation. The read image is converged by the lens 248 and then incident on the image sensor 249, subjected to photoelectric conversion, and stored in the image memory 214 as an image data signal for one original after passing through an A / D converter (not shown). .

  When the image data signal for one document is stored in the image memory 214, the control unit 339 determines whether or not a solid image portion exists in the document image. If it is determined that there is no solid image portion in the original image at this time, the single-sided printing operation program for the solid image portion without the solid image portion is performed only at a position corresponding to the front end portion of the paper. Is read, and it is determined that the original image has a solid image portion, the ejection of air from the second peeling member 211 to the paper P is performed at a position corresponding to the front end portion of the paper and a position corresponding to the solid image portion. A single-sided printing operation program for an image portion is read.

  Since the single-sided printing operation of the stencil printing apparatus 201 in the case of no solid image part is the same as the single-sided printing operation of the stencil printing apparatus 201 in the seventh embodiment described above, the description here is omitted and there is a solid image part. Only the single-sided printing operation of the stencil printing apparatus 201 in this case will be described.

  In parallel with the image reading operation in the image reading unit 207, the plate discharging unit 205 performs a plate discharging operation. When the plate removal operation is completed, the plate feeding operation is performed, and the pre-printed master 221 is wound on the outer peripheral surface of the plate cylinder 212. When the plate feeding operation is completed, one sheet P is pulled out from the sheet feeding tray 229, and the sheet P is temporarily stopped by the registration roller pair 233 and then fed toward the printing unit 202. At this time, the swinging means (not shown) sets the pressing range of the press roller 213 against the plate cylinder 212 to the first range.

  The fed paper P is pressed by the pre-printed master 221 wound around the outer peripheral surface of the plate cylinder 212 rotating at a low speed by the press roller 213, and printing is performed. The paper P on which the printed image is formed and becomes the printed paper PB is peeled off from the plate-making master 221 on the outer peripheral surface of the plate cylinder by the second peeling member 211 from the front end portion thereof. At the time of peeling, the second piston drive motor 274 is operated, and the second piston 268 reciprocates twice in the second cylinder 267, whereby air is jetted twice from the opening 211c, and printed paper PB from the outer peripheral surface of the plate cylinder Is peeled well.

  The operation of the second piston drive motor 274 is performed when the leading end of the printed paper PB reaches a position corresponding to the opening 211c and the solid image part is formed with the opening 211c with reference to a plate cylinder angle signal from a rotary encoder (not shown). Control means 339 controls the second rotary plate position detection sensor 278 to detect the dog 277 when the corresponding position is reached. By the control of the control means 339, the position corresponding to the solid image portion of the printed paper PB and the position between the leading end of the printed paper PB and the master 221 on the outer periphery of the plate cylinder and the plate making on the outer surface of the plate cylinder. Air is ejected from the opening 211c toward the finished master 221.

  The peeled printed paper PB falls downward and is received by the paper discharge transport member 239, and then transported and discharged onto the paper discharge tray 240. Thereafter, the plate cylinder 212 is rotated again to the home position and stopped. After the plate making operation is completed, the stencil printing apparatus 201 enters a single-sided printing standby state.

  When the trial printing key on the operation panel 281 is pressed after the stencil printing apparatus 201 enters the single-sided printing standby state, the plate cylinder 212 is driven to rotate at a peripheral speed corresponding to the set printing speed and the paper feeding unit When only one sheet P is fed from 204 and trial printing is performed, and the print start key is pressed, the plate cylinder 212 is driven to rotate at a peripheral speed corresponding to the set printing speed and the paper feeding unit 204 is driven. The sheet P is continuously fed from one side and a single-sided printing operation is performed. During the trial printing and the single-sided printing operation, air is sent from the second air supply means 266 when the printed paper PB is peeled from the outer peripheral surface of the plate cylinder, and the printed paper PB is peeled off. Is done well.

Next, a case where duplex printing is set on the operation panel 281 will be described.
When the operator presses the plate-making start key after the first document is set on the contact glass 241, the image reading unit 207 performs a reading operation in the same way as during single-sided printing, and the read image is stored in the image memory. The first image data signal is stored in 214. Thereafter, when the second original is set on the contact glass 241 and the pressure plate 242 is closed, the reading operation is performed in the same manner, and the read image is stored in the image memory 214 as the second image data signal. Is done.

  When the image data signals for the two originals are stored in the image memory 214, the control unit 339 determines whether there is a solid image portion in the original image. At this time, if it is determined that there is no solid image portion in each original image, there is no solid image portion in which the ejection of air from the first peeling member 210 and the second peeling member 211 is performed only at a position corresponding to the leading edge portion of the paper. When the double-sided printing operation program is read and it is determined that there is a solid image portion only on the original image as the first plate-making image, the position at which the ejection of air from the first peeling member 210 corresponds to the front end portion of the paper and The first double-sided printing operation program for the presence of a solid image portion, which is performed at a position corresponding to the solid image portion and is ejected only at a position corresponding to the front end portion of the sheet, is read. If it is determined that there is a solid image portion only in the original image that is a plate-making image, air is ejected from the first peeling member 210 only at a position corresponding to the front end portion of the sheet. The second duplex printing operation program for the presence of a solid image portion in which the ejection of air from the separation member 211 is performed at a position corresponding to the front end portion of the sheet and a position corresponding to the solid image portion is read, and the image portion solid to each original image If there is a solid image portion, the ejection of air from the first peeling member 210 and the second peeling member 211 is performed at a position corresponding to the front end of the sheet and a position corresponding to the solid image portion, respectively. A third duplex printing operation program is read.

  The double-sided printing operation of the stencil printing apparatus 201 in the case of no solid image part is the same as the double-sided printing operation of the stencil printing apparatus 201 in the seventh embodiment described above, so the description here is omitted and there is a solid image part. The duplex printing operation of the stencil printing apparatus 201 in this case will be described below.

  In parallel with the image reading operation in the image reading unit 207, the plate discharging unit 205 performs a plate discharging operation. When the plate removal operation is completed, the plate feeding operation is performed, and the divided plate-making master 221 is wound on the outer peripheral surface of the plate cylinder 212. When the plate feeding operation is completed, one sheet P is pulled out from the sheet feeding tray 229, and the sheet P is temporarily stopped by the registration roller pair 233 and then fed toward the printing unit 202. At this time, the swinging means (not shown) sets the pressing range of the press roller 213 against the plate cylinder 212 to the second range, and the first peeling member 210 occupies the close position when the clamper passes the corresponding position.

  The fed paper P is pressed against the first plate-making image of the divided plate-making master 221 wound around the outer peripheral surface of the plate cylinder 212 rotating at a low speed by the press roller 213. The paper P that has been printed with the front surface image and becomes the surface-printed paper PA is peeled from the front end of the divided plate-making master 221 on the outer peripheral surface of the plate cylinder by the first peeling member 210. At the time of peeling, the first piston drive motor 260 is operated, and in the case of the first and third double-sided printing operation programs, the first piston 254 reciprocates twice in the first cylinder 253, so that air is jetted twice from the opening 210c. In the case of the second double-sided printing operation program, the first piston 254 reciprocates once in the first cylinder 253 so that air is ejected from the opening 210c once, and the surface-printed paper PA is peeled from the outer peripheral surface of the plate cylinder. Is done well.

  The operation of the first piston drive motor 260 is performed when the front end portion of the surface-printed paper PA reaches a position corresponding to the opening 210c and the solid image portion is the opening 210c with reference to a plate cylinder angle signal from a rotary encoder (not shown). The control means 339 controls the first rotary plate position detection sensor 264 to detect the dog 263 when it reaches the position corresponding to. Under the control of the control means 339, the position corresponding to the solid image portion of the surface-printed paper PA and the position between the front end portion of the surface-printed paper PA and the divided plate-making master 221 on the plate-cylindrical outer peripheral surface. Air is ejected from the opening 210c toward the upper divided master 221. The peeled surface-printed paper PA is dropped downward and placed on the auxiliary tray 208, and is then transported by the re-feed transport member 218 and the other end is in contact with the re-feed positioning member 219. It is temporarily stopped at. After that, the re-feeding registration roller 217 is swung at the same timing as in the seventh embodiment, and is brought into pressure contact with the peripheral surface of the press roller 213.

  The surface-printed paper PA conveyed toward the contact portion between the plate cylinder 212 and the press roller 213 by the rotational force of the press roller 213 is divided around the outer peripheral surface of the plate cylinder 212 rotating at a low speed. It is pressed against the second plate-making image of the plate-making master 221. The front-side printed paper PA that has been printed with the back image and becomes the printed paper PB is peeled from the front end of the divided plate-making master 221 on the outer peripheral surface of the plate cylinder by the second peeling member 211. At the time of peeling, the second piston drive motor 274 is operated, and in the case of the second and third double-sided printing operation programs, the second piston 268 reciprocates twice in the second cylinder 267 so that air is jetted twice from the opening 211c. In the case of the first double-sided printing operation program, the second piston 268 reciprocates once in the second cylinder 267 so that air is blown out once from the opening 211c, and the surface-printed paper PA is peeled from the outer peripheral surface of the plate cylinder. Is done well.

  The operation of the second piston drive motor 274 is performed when the leading end of the printed paper PB reaches a position corresponding to the opening 211c and the solid image part is formed with the opening 211c with reference to a plate cylinder angle signal from a rotary encoder (not shown). Control means 339 controls the second rotary plate position detection sensor 278 to detect the dog 277 when the corresponding position is reached. By the control of the control means 339, the position corresponding to the solid image portion of the printed paper PB and the position between the front end portion of the printed paper PB and the divided plate-making master 221 on the outer surface of the plate cylinder, and the outer surface of the plate cylinder. Air is ejected from the opening 210c toward the divided master-making master 221.

  The peeled printed paper PB falls downward and is received by the paper discharge transport member 239, and then transported and discharged onto the paper discharge tray 240. Thereafter, the plate cylinder 212 is rotated again to the home position and stopped. After the plate making operation is finished, the stencil printing apparatus 201 enters a duplex printing standby state.

  After the stencil printing apparatus 201 enters the duplex printing standby state, when a trial printing key is pressed after inputting printing conditions using various keys on the operation panel 281, the plate cylinder is rotated at a peripheral speed corresponding to the set printing speed. 212 is rotated and only one sheet P is fed from the sheet feeding unit 204 to perform a test printing. This test printing is performed in the same manner as the plate-forming operation except that the rotational peripheral speed of the plate cylinder 212 is different. Even during this test printing, the first air supply means 252 removes the surface-printed paper PA from the first air supply means 252. Air is sent twice during the first and third duplex printing operation programs, and once during the second duplex printing operation program, and the second and third duplex printing operations are performed from the second air supply means 266 when the printed paper PB is peeled off. Air is sent twice at the time of programming and once at the time of the first double-sided printing operation program, and the surface-printed paper PA and the printed paper PB are peeled off from the outer peripheral surface of the plate cylinder. Then, after the peeled printed paper PB is discharged onto the paper discharge tray 240, the plate cylinder 212 stops at the home position, so that the trial printing operation is finished and the stencil printing apparatus 201 enters the duplex printing standby state again. .

  When the position or density of the image is confirmed by trial printing and the print start key is pressed after the number of prints is input on the operation panel 281, a printing operation is performed. This printing operation is different from the printing operation described in the seventh embodiment only in that air is sent once or twice from each air supply means 252 and 266 in the same manner as when printing. Other operations are the same.

  According to the configuration described above, during single-sided printing of a document having a solid image portion, air is ejected from the second peeling member 211 at a position corresponding to the front end portion of the paper and a position corresponding to the solid image portion, and the first plate-making image is formed. At the time of duplex printing of a document having a solid image portion, the position corresponding to the front end portion of the paper at the time of front surface printing and the position corresponding to the front end portion of the paper at the position corresponding to the solid image portion from the first peeling member 210 At the time of double-sided printing of a document having an image portion solid only on the second plate-making image, air is ejected from the second peeling member 211 at the position corresponding to the front end of the paper from the first peeling member 210 or Air is ejected from the second peeling member 211 at the position corresponding to the front end of the paper and the position corresponding to the solid image portion during backside printing, At the time of double-sided printing of a document having a solid image portion on the image, air is ejected from each of the peeling members 210 and 211 at a position corresponding to the front end portion of the paper and a position corresponding to the solid image portion at the time of printing on the front and back surfaces. The same effect as that of the seventh embodiment can be obtained, and the ink can be used even when the paper P has a solid image portion that extends substantially rearward from the central portion of the paper P in the paper conveyance direction. The sheet P adhered to the divided plate-making master 221 on the outer peripheral surface of the plate cylinder can be peeled off satisfactorily by the adhesive force of the plate cylinder. A good printed matter can be obtained by preventing the occurrence of a problem of being stuck and causing a conveyance jam.

  In the present embodiment, when one-sided printing of a document that does not have a solid image portion, the second piston 268 makes one reciprocation within the second cylinder 267 during one rotation of the plate cylinder 212, and a document that does not have a solid image portion. During double-sided printing, the first piston 254 reciprocates once in the first cylinder 253 during one rotation of the plate cylinder 212 and the second piston 268 reciprocates once in the second cylinder 267. When single-sided printing of a document having a solid image portion is performed. During one rotation of the plate cylinder 212, the second piston 268 makes two reciprocations in the second cylinder 267, and when printing on both sides of a document having a solid image portion, the first piston 254 is moved into the first cylinder 253 during one rotation of the plate cylinder 212. And the second piston 268 reciprocates once or twice within the second cylinder 267.

  Here, since the rotational peripheral speed of the plate cylinder 212 can be changed according to the printing speed, the time during which the plate cylinder 212 makes one rotation also changes according to the printing speed. For this reason, in this embodiment, the rotational peripheral speeds of the piston drive motors 260 and 274 are such that the reciprocating speed of the pistons 254 and 268 is a constant speed that is twice or more the maximum rotational peripheral speed of the plate cylinder 212. Is controlled to rotate intermittently at a constant speed. It should be noted that the rotational peripheral speeds of the piston drive motors 260 and 274 may be changed according to the rotational peripheral speed of the plate cylinder 212. In this case, the moving speed of the pistons 254 and 268 is also reduced, and the jet pressure of air from the openings 210c and 211c may be reduced to prevent good printing. In such a case, it is necessary to increase the rotational peripheral speeds of the piston drive motors 260 and 274 as appropriate so as to keep the air ejection pressure from the openings 210c and 211c above a certain value.

  Next, an eleventh embodiment of the present invention will be described. The eleventh embodiment is different from the tenth embodiment described above only in that the air supply units 283 and 311 shown in the ninth embodiment are used instead of the air supply units 252 and 266. The other configurations are the same. The operation of the stencil printing apparatus 201 in the eleventh embodiment will be described below. First, a case where single-sided printing is set on the operation panel 281 will be described.

  When the plate making start key is pressed by the operator, the image reading unit 207 reads an original image, and the read original image is stored in the image memory 214 as an image data signal. Next, the control unit 339 determines whether or not a solid image portion exists in the original image, and reads a single-sided printing operation program without a solid image portion or a single-sided printing operation program with a solid image portion.

  The operation of the stencil printing apparatus 201 when there is no solid image portion is the same as the single-sided printing operation of the stencil printing apparatus 201 when using small-size paper in the ninth embodiment, and a description thereof is omitted here. Only the operation of the stencil printing apparatus 201 when there is a solid image portion will be described.

  In parallel with the image reading operation in the image reading unit 207, the plate discharging unit 205 performs the plate discharging operation, and the plate feeding operation is performed after the plate discharging operation is completed. When the plate feeding operation is completed, one sheet P is pulled out from the sheet feeding tray 229, and the sheet P is temporarily stopped by the registration roller pair 233 and then fed toward the printing unit 202.

  The fed paper P is pressed by the pre-printed master 221 wound around the outer peripheral surface of the plate cylinder 212 rotating at a low speed by the press roller 213, and printing is performed. The paper P on which the printed image is formed and becomes the printed paper PB is peeled off from the plate-making master 221 on the outer peripheral surface of the plate cylinder by the second peeling member 211 from the front end portion thereof. At the time of separation, the second piston drive motor 327 and the fourth piston drive motor 330 are operated, respectively, and the second piston 313 and the fourth piston 319 reciprocate in the corresponding cylinders, respectively, so that air flows twice from the opening 211c. The printed paper PB is ejected favorably from the outer peripheral surface of the plate cylinder.

  The operations of the second piston drive motor 327 and the fourth piston drive motor 330 are performed when the leading end of the printed paper PB reaches a position corresponding to the opening 211c with reference to a plate cylinder angle signal from a rotary encoder (not shown). The fourth rotation plate position detection sensor 336 is set so that the second rotation plate position detection sensor 335 detects the dog 333 and when the solid image portion of the printed paper PB reaches a position corresponding to the opening 211c. Control is performed by the control means 339 so that the timing for detecting the dog 334 is reached. By the control of the control means 339, the position corresponding to the solid image portion of the printed paper PB and the position between the leading end of the printed paper PB and the master 221 on the outer periphery of the plate cylinder and the plate making on the outer surface of the plate cylinder. Air is ejected from the opening 221c toward the finished master 221.

  The peeled printed paper PB falls downward and is received by the paper discharge transport member 239, and then transported and discharged onto the paper discharge tray 240. Thereafter, the plate cylinder 212 is rotated again to the home position and stopped. After the plate making operation is completed, the stencil printing apparatus 201 enters a single-sided printing standby state.

  When the trial printing key on the operation panel 281 is pressed after the stencil printing apparatus 201 enters the single-sided printing standby state, the plate cylinder 212 is driven to rotate at a peripheral speed corresponding to the set printing speed and the paper feeding unit When only one sheet P is fed from 204 and trial printing is performed, and the print start key is pressed, the plate cylinder 212 is driven to rotate at a peripheral speed corresponding to the set printing speed and the paper feeding unit 204 is driven. The sheet P is continuously fed from one side and a single-sided printing operation is performed. Even during the trial printing and the single-sided printing operation, when the printed paper PB is peeled off from the outer peripheral surface of the plate cylinder, air is sent twice from the second air supply means 311 in the same manner as the printing, and the printed paper PB is peeled well.

Next, a case where duplex printing is set on the operation panel 281 will be described.
Similar to the tenth embodiment, the image reading unit 207 performs a reading operation on two originals, and the read original images are stored in the image memory 214 as image data signals for two sheets. Next, the presence or absence of a solid image portion is determined by the control means 339, and the duplex printing operation program for the absence of the solid image portion or the first to third duplex printing operation programs for the presence of the solid image portion are read.

  Since the operation of the stencil printing apparatus 201 when there is no solid image portion is the same as the double-sided printing operation of the stencil printing apparatus 201 when using small-size paper in the ninth embodiment, description thereof is omitted here. Only the operation of the stencil printing apparatus 201 when there is a solid image portion will be described.

  In parallel with the image reading operation in the image reading unit 207, the plate discharging unit 205 performs the plate discharging operation, and the plate feeding operation is performed after the plate discharging operation is completed. When the plate feeding operation is completed, one sheet P is pulled out from the sheet feeding tray 229, and the sheet P is temporarily stopped by the registration roller pair 233 and then fed toward the printing unit 202.

  The fed paper P is pressed by the divided plate-making master 221 wound around the outer peripheral surface of the plate cylinder 212 rotating at a low speed by the press roller 213, and the first plate-making image is printed. The paper P that has been formed with the front surface printed image to become the front surface printed paper PA is peeled from the front end of the divided plate-making master 221 on the outer peripheral surface of the plate cylinder by the first peeling member 210. At the time of peeling, in the case of the first and third printing operation programs, the first piston drive motor 299 and the third piston drive motor 302 are operated, respectively, and the first piston 285 and the third piston 291 are respectively moved in the corresponding cylinders. By reciprocating, air is jetted twice from the opening 210c, and in the case of the second double-sided printing operation program, either the first piston driving motor 299 or the third piston driving motor 302 is operated, and the first piston 285 or When any one of the third pistons 291 reciprocates in the corresponding cylinder, air is ejected once from the opening 210c, and the surface printed paper PA is peeled off from the outer peripheral surface of the plate cylinder.

  The operations of the first piston drive motor 299 and the third piston drive motor 302 are performed when the front end of the surface-printed paper PA reaches a position corresponding to the opening 210c with reference to a plate cylinder angle signal from a rotary encoder (not shown). The third rotation plate position detection sensor 307 is set to the timing at which the first rotation plate position detection sensor 307 detects the dog 305, and when the solid image portion of the surface-printed paper PA reaches a position corresponding to the opening 210c. The control unit 282 controls the 308 so that the dog 306 is detected. Under the control of the control means 282, the divided plate-making process between the front end portion of the surface-printed paper PA and the divided plate-making master 221 on the outer surface of the plate cylinder and the divided image portion of the surface-printed paper PA and the outer surface of the plate cylinder. Air is ejected from the opening 210 c toward the finished master 221.

  The peeled surface-printed paper PA is dropped downward and placed on the auxiliary tray 208, and is then transported by the re-feed transport member 218 and the other end is in contact with the re-feed positioning member 219. It is temporarily stopped at. Thereafter, the re-feeding registration roller 217 is swung at the same timing as in the seventh embodiment, so that the surface-printed paper PA is brought into contact with the plate cylinder 212 and the press roller 213 by the rotational force of the press roller 213. It is conveyed toward.

  The conveyed surface-printed paper PA is pressed by the divided plate-making master 221 wound around the outer peripheral surface of the plate cylinder 212 rotating at a low speed by the press roller 213, and the printing of the second plate-making image is performed. The front-side printed paper PA that has been formed with the back-side printed image and becomes the printed paper PB is peeled from the front end of the divided plate-making master 221 on the outer peripheral surface of the plate cylinder by the second peeling member 211. At the time of peeling, in the case of the second and third printing operation programs, the second piston drive motor 327 and the fourth piston drive motor 330 are operated, respectively, and the second piston 313 and the fourth piston 319 are respectively moved in the corresponding cylinders. By reciprocating, air is ejected twice from the opening 211c, and in the case of the first printing operation program, either the second piston drive motor 327 or the fourth piston drive motor 330 operates, and the second piston 313 or the second piston 313 As one of the four pistons 319 reciprocates in the corresponding cylinder, air is ejected once from the opening 211c, and the printed paper PB is favorably peeled from the outer peripheral surface of the plate cylinder.

  The operations of the second piston drive motor 327 and the fourth piston drive motor 330 are performed when the leading end of the printed paper PB reaches a position corresponding to the opening 211c with reference to a plate cylinder angle signal from a rotary encoder (not shown). The fourth rotation plate position detection sensor 336 is set so that the second rotation plate position detection sensor 335 detects the dog 333 and when the solid image portion of the printed paper PB reaches a position corresponding to the opening 211c. Control is performed by the control means 282 so that the timing for detecting the dog 334 is reached. Under the control of the control means 282, the divided plate-making master on the printed image sheet PB and the divided plate-making master 221 on the outer peripheral surface of the plate cylinder and on the solid image portion of the printed paper PB and the outer surface of the plate cylinder. Air is ejected from the opening 211 c toward the space 221.

  The peeled printed paper PB falls downward and is received by the paper discharge transport member 239, and then transported and discharged onto the paper discharge tray 240. Thereafter, the plate cylinder 212 is rotated again to the home position and stopped. After the plate making operation is finished, the stencil printing apparatus 201 enters a duplex printing standby state.

  When the trial printing key on the operation panel 281 is pressed after the stencil printing apparatus 201 enters the duplex printing standby state, the plate cylinder 212 is driven to rotate at a peripheral speed corresponding to the set printing speed and the paper feeding unit When only one sheet P is fed from 204 and trial printing is performed, and the print start key is pressed, the plate cylinder 212 is driven to rotate at a peripheral speed corresponding to the set printing speed and the paper feeding unit 204 is driven. The sheet P is continuously fed from the beginning and the duplex printing operation is performed. The test printing is performed in the same manner as the above-described plate-fixing operation except that the rotational peripheral speed of the plate cylinder 212 is different, and the double-sided printing operation is performed twice from each air supply means 283, 311 in the same manner as during plate-printing. Is performed in the same manner as the double-sided printing operation described in the seventh embodiment except that is sent.

  In the above embodiment, when the leading end of the printed paper PB reaches the position corresponding to the opening 211c during single-sided printing and double-sided printing with a solid image portion, the fourth rotary plate position detection sensor 336 is dogged. 334 so that the second rotary plate position detection sensor 335 detects the dog 333 when the solid image portion of the printed paper PB reaches a position corresponding to the opening 211c. The controller 282 may control the piston drive motors 327 and 330.

  In the above-described embodiment, the third rotary plate position detection sensor 308 detects the dog 306 when the front end of the surface-printed paper PA reaches a position corresponding to the opening 210c during double-sided printing when there is a solid image portion. Control so that the first rotary plate position detection sensor 307 detects the dog 305 when the solid image portion of the front surface printed paper PA reaches a position corresponding to the opening 210c. The means 282 may control the piston drive motors 299 and 302.

  Also in the present embodiment, as in the tenth embodiment, during single-sided printing of a document that does not have a solid image portion and during single-sided printing of a document that has a solid image portion at a position corresponding to the leading edge of the paper during double-sided printing. Also, during double-sided printing, air is ejected from the peeling members 210 and 211 at positions corresponding to the leading edge of the paper and the solid image portion on the paper, so that the same operational effects as those of the tenth embodiment can be obtained.

  In this embodiment, during single-sided printing of a document that does not have a solid image portion, one of the pistons 313 and 319 reciprocates once within the corresponding cylinder 312 and 318 during one rotation of the plate cylinder 212, During double-sided printing of a document that does not have a solid image portion, one of the pistons 285 and 291 reciprocates once within the corresponding cylinder 284 and 290 during one rotation of the plate cylinder 212 and each piston 313 and 319. One of the cylinders 312 and 318 is reciprocated once in the corresponding cylinders 312 and 318, and during the one-side printing of the original having a solid image portion, each piston 313 and 319 is in the corresponding cylinder 312 and 318 during one rotation of the plate cylinder 212. The cylinders 284 to which the pistons 285 and 291 correspond during one rotation of the plate cylinder 212 during double-sided printing of a document having a solid image portion. Each piston 313,319 is employed each one reciprocation constituting the cylinder 312, 318 corresponding with the 90 reciprocates once, respectively.

  Also in this embodiment, since the rotational peripheral speed of the plate cylinder 212 can be changed according to the printing speed, the time during which the plate cylinder 212 makes one revolution also changes according to the printing speed. For this reason, in this embodiment, the piston drive motors 299, 302, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, Control is performed so that the rotational circumferential speed of 330 is intermittently driven at a constant speed.

  It should be noted that the rotational peripheral speeds of the piston drive motors 299, 302, 327, and 330 may be changed according to the rotational peripheral speed of the plate cylinder 212. During the low-speed rotation, the moving speeds of the pistons 285, 291, 313 and 319 are also reduced, and the jet pressure of air from the openings 210c and 211c may be reduced, and good printing may not be performed. In such a case, it is necessary to increase the rotational peripheral speeds of the piston drive motors 299, 302, 327, and 330 as appropriate, and to maintain the air ejection pressure from the openings 210c and 211c at a certain value or more.

  In the tenth and eleventh embodiments described above, the first piston 254 is driven by the first piston drive motor 260, the second piston 268 is driven by the second piston drive motor 274, and the first piston 285 is driven by the first piston drive motor 299. The second piston 313 is reciprocated by the second piston drive motor 327, the third piston 291 is reciprocated by the third piston drive motor 302, and the fourth piston 319 is reciprocated by the fourth piston drive motor 330. Without using the drive motors 260, 274, 299, 327, 302, and 330, the rotational drive force from the plate cylinder drive means (not shown) is transmitted by drive force transmission means such as gears and belts, and the pistons 254, 268, 285, respectively. It may be configured to reciprocate 313,291,319 .

  When this configuration is adopted in the tenth embodiment, when one-sided printing of a document that does not have a solid image portion, the second piston 268 is placed during one rotation of the plate cylinder, and a document that does not have a solid image portion is printed. During double-sided printing, the first piston 254 and the second piston 268 are reciprocated once during one rotation of the plate cylinder, and during single-sided printing of a document having a solid image portion, the second piston 268 is rotated during the single rotation of the plate cylinder. Since the first piston 254 and the second piston 268 need to reciprocate twice during one rotation of the plate cylinder during double-sided printing of the original document, the driving force transmission means uses a rotational driving force for one rotation of the plate cylinder as the piston 1 reciprocates. A path for transmitting as a driving force for one minute and a path for transmitting while increasing as a driving force for two reciprocations of the piston, and a structure for switching the driving force transmitting path by a switching means; There is a need.

  Further, in both the tenth and eleventh embodiments, in the case of a document having a solid image portion, it is necessary to blow air at a position corresponding to the solid image portion of the paper P. Therefore, depending on the position of the solid image portion. It is necessary to change the location of the air ejection. In this case, it is necessary to control the reciprocation of the pistons 254, 268, 285, 313, 291 and 319 by using connecting means such as a clutch for connecting or disconnecting the driving force as the driving force transmitting means.

  FIG. 24 shows a block diagram of the control means used in the twelfth embodiment of the present invention. The control means 340 stores various signals from the operation panel 281, signals from various sensors such as a paper size detection sensor 234, rotary plate position detection sensors 264 and 278, a home position sensor 251, a rotary encoder (not shown), and the like. The operation of the printing unit 202, the plate making unit 203, the paper feeding unit 204, the plate discharging unit 205, the paper discharge unit 206, the image reading unit 207, and each of the air supply units 252 and 266 is controlled based on the operation program being executed. The overall operation of the printing apparatus 201 is controlled.

  Further, the control means 340 determines whether or not the original has a solid image portion from the image data signal stored in the image memory 214 and in which portion the solid image portion exists using a predetermined threshold value. When there is a solid image portion, it has a function of detecting its position.

  In the present embodiment, the timing at which air is ejected from the opening 210c is the sheet fed from the sheet feeding unit 204 to the first plate-making image of the divided plate-making master 221 wound on the plate cylinder 212 during double-sided printing. When P is pressed by the press roller 213 and then peeled off from the plate cylinder 212 by the first peeling member 210, the leading end of the paper P that has become the surface-printed paper PA occupies a position corresponding to the opening 210c. When printing on both sides, the paper P is a large size (in this embodiment, A4 side (when the short side direction of the paper is set as the paper conveyance direction) or more). When the middle of the paper conveyance direction length of the paper PA occupies a position corresponding to the opening 210c, and when there is a solid image portion in the first plate-making image of the divided plate-making master 221 The solid image portion is defined when occupied a position corresponding to the opening 210c. Note that when a large-size sheet is used as the sheet P and a solid image portion exists in the first plate-making image of the divided plate-making master 221, the timing of ejecting air from the opening 210c is the timing of the surface-printed sheet PA. It is determined when the leading end occupies a position corresponding to the opening 210c and when the middle of the length of the front-side printed paper PA in the sheet conveyance direction occupies a position corresponding to the opening 210c.

  Accordingly, the first piston drive motor 260 rotates the plate cylinder 212 once when a small-size sheet is used as the sheet P during double-sided printing and there is no solid image portion in the first plate-making image of the divided plate-making master 221. In the meantime, the first rotating plate 256 is rotated once to reciprocate the first piston 254 once in the first cylinder 253, and when a large-sized sheet is used as the sheet P and / or the first of the divided plate-making master 221 is used. When a solid image portion exists in the plate-making image, the first rotating plate 256 is rotated twice while the plate cylinder 212 rotates once, and the first piston 254 is reciprocated twice in the first cylinder 253. If it is determined by the presence / absence of a solid image portion that two or more solid image portions exist in the first plate-making image of the divided plate-making master 221, the ejection of air from the opening 210c is the most downstream in the sheet conveyance direction. This is performed only for the solid image portion located on the side (when using small size paper).

  Further, in the present embodiment, the timing of ejecting air from the opening 211c is fed from the paper feeding unit 204 to the third plate-making image of the plate-making master 221 wound on the plate cylinder 212 during single-sided printing. After the sheet P is pressed by the press roller 213, the leading end of the sheet P that has become the printed sheet PB when the sheet P is separated from the plate cylinder 212 by the second peeling member 211 occupies a position corresponding to the opening 211c. When the paper P is printed on one side using a large-size paper (in this embodiment, the length of the paper in the paper transport direction is equal to or larger than A4 (when the short side direction of the paper is the paper transport direction)) A solid image portion exists in the third plate-making image of the plate-making master 221 when the middle of the length in the sheet conveyance direction occupies a position corresponding to the opening 211c and during single-sided printing. In this case, when the solid image portion printed on the printed paper PB occupies a position corresponding to the opening 211c, and at the time of double-sided printing, the second plate-making image of the divided plate-making master 221 wound on the plate cylinder 212 is used. On the other hand, the surface-printed paper PA fed from the re-feeding means 209 is pressed by the press roller 213 and then becomes the printed paper PB when peeled off from the plate cylinder 212 by the second peeling member 211. When the front end of the front-side printed paper PA occupies a position corresponding to the opening 211c, and when the double-sided printing in which a large-size paper is used as the paper P, the middle of the length of the printed paper PB in the paper conveyance direction is approximately halfway. When the position corresponding to the opening 211c is occupied, and when there is a solid image portion in the second plate-making image of the divided plate-making master 221, the solid image portion corresponds to the opening 211c. It is defined when the position accounted for that.

  When a large-size sheet is used as the sheet P and a solid image portion is present in the second plate-making image of the divided plate-making master 221, the timing of ejecting air from the opening 211 c is the leading edge of the printed sheet PB. This is determined when the portion occupies the position corresponding to the opening 211c and when the middle of the length of the printed paper PB in the sheet conveyance direction occupies the position corresponding to the opening 211c.

  Therefore, the second piston drive motor 274 is used when the small size paper is used as the paper P during single-sided printing and there is no solid image portion in the third plate-making image of the master 221 and when the double-sided printing is performed. When a sheet is used and there is no solid image portion in the second plate-making image of the divided plate-making master 221, the second rotating plate 270 is rotated once to rotate the second piston 268 while the plate cylinder 212 is rotated once. When the large size paper is used as the paper P at the time of single-sided and double-sided printing, and when the small size paper is used as the paper P at the time of single-sided printing, the third plate-making image of the master 221 is made. A second plate-making image of the master 221 in which a small-size paper is used as the paper P when a solid image portion exists and double-sided printing is performed Plate cylinder 212 causes the two round trips in the second piston 268 of the second rotary plate 270 rotated twice in the second cylinder 267 during one rotation in the case of solid image portion is present.

  If it is determined by the presence / absence detection of the solid image portion that two or more solid image portions exist in the third plate making image of the master plate 221 and the second plate image of the divided master plate 221, the opening 211c is used. The air is ejected only to the solid image portion located on the most downstream side in the paper transport direction (when using small size paper).

  Based on the above configuration, the operation of the stencil printing apparatus 201 in the twelfth embodiment will be described below. First, a case where single-sided printing is set on the operation panel 281 will be described. After placing the document to be printed on the contact glass 241, the operator sets the plate making conditions using various keys on the operation panel 281 and presses the plate making start key.

  When the plate making start key is pressed, the control means 340 confirms the size of the paper P loaded on the paper feed tray 229 based on the paper size detection signal from the paper size detection sensor 234. First, a case where the paper P is a small size paper will be described.

  When the plate making start key is pressed, the image reading unit 207 performs a document image reading operation. The read original image is converged by the lens 248, then incident on the image sensor 249, subjected to photoelectric conversion, passed through an A / D converter (not shown), and then stored in the image memory 214 as an image data signal for one original. The

  When the image data signal for one document is stored in the image memory 214, the control unit 340 determines whether or not a solid image portion exists in the document image. At this time, if it is determined that there is no solid image portion in the original image, the ejection of air from the second peeling member 211 to the printed paper PB is performed only at a position corresponding to the front end portion of the small size paper. When the one-side printing operation program is read and it is determined that the original image has a solid image portion, the position where the air blown from the second peeling member 211 to the printed paper PB corresponds to the front end portion of the paper and the solid image portion A single-sided printing operation program for the presence of a small-size sheet solid image portion performed at a corresponding position is read.

  The single-sided printing operation of the stencil printing apparatus 201 when there is no small-size paper solid image part is the same as the single-sided printing operation of the stencil printing apparatus 201 in the seventh embodiment, and the stencil printing apparatus when there is a small-size paper solid image part The single-sided printing operation 201 is the same as the single-sided printing operation of the stencil printing apparatus 201 when there is a solid image portion in the tenth embodiment.

  Next, a case where the paper P is a large size paper will be described. When the plate making start key is pressed, the image reading unit 207 performs a document image reading operation, and the read image passes through the lens 248, the image sensor 249, and an A / D converter (not shown), and then one original document. Is stored in the image memory 214 as an image data signal. When this large size sheet is used, the control unit 340 does not determine whether a solid image portion exists in the document image.

  For large-sized paper, the ejection of air from the second peeling member 211 to the printed paper PB is performed at a position corresponding to the front end of the paper and a position substantially corresponding to the middle of the length of the printed paper PB in the paper conveyance direction. The single-sided printing operation program is read. The operation of the stencil printing apparatus 201 in this case is the same as the single-sided printing operation of the stencil printing apparatus 201 when using large-size paper in the eighth embodiment.

  Next, a case where duplex printing is set on the operation panel 281 will be described. After placing the first document to be printed on the contact glass 241, the operator sets the platemaking conditions using various keys on the operation panel 281 and presses the platemaking start key. When the plate making start key is pressed, the control means 340 confirms the size of the paper P loaded on the paper feed tray 229 based on the paper size detection signal from the paper size detection sensor 234. First, a case where the paper P is a small size paper will be described.

  When the plate making start key is pressed after the first document is set on the contact glass 241, the image reading unit 207 performs a reading operation in the same manner as in single-sided printing, and the read image is stored in the image memory 214. Is stored as the first image data signal. Thereafter, when the second original is set on the contact glass 241 and the pressure plate 242 is closed, the reading operation is performed in the same manner, and the read image is stored in the image memory 214 as the second image data signal. Is done.

  When the image data signals for the two originals are stored in the image memory 214, the control unit 340 determines whether there is a solid image portion in the original image. At this time, if it is determined that there is no solid image portion in each original image, the small size paper solid is produced in which the ejection of air from the first peeling member 210 and the second peeling member 211 is performed only at the position corresponding to the leading edge of the paper. When the double-sided printing operation program for no image portion is read and it is determined that the original image serving as the first plate-making image has a solid image portion, the ejection of air from the first peeling member 210 corresponds to the leading edge portion of the paper. The first double-sided printing operation program for the presence of the small-size paper solid image portion, which is performed at the position corresponding to the solid image portion and the position where the air is ejected from the second peeling member 211 only at the position corresponding to the front end portion of the paper. Is read, and it is determined that there is a solid image portion only on the original image to be the second plate-making image, the blowout of air from the first peeling member 210 corresponds to the leading edge portion of the paper. The second double-sided printing operation program for reading a small-size paper solid image portion is read, which is performed only at the position and the air blowing from the second peeling member 211 is performed at a position corresponding to the front end portion of the paper and a position corresponding to the solid image portion. If it is determined that each original image has a solid image portion, the ejection of air from the first peeling member 210 and the second peeling member 211 is at a position corresponding to the front end portion of the sheet and a position corresponding to the solid image portion. The third double-sided printing operation program for the presence of the small-size sheet solid image portion to be performed is read.

  The double-sided printing operation of the stencil printing apparatus 201 when there is no small-size paper solid image part is the same as the double-sided printing operation of the stencil printing apparatus 201 in the seventh embodiment, and the stencil printing apparatus when there is a small-size paper solid image part The first double-sided printing operation 201 is the same as the first double-sided printing operation when the stencil printing apparatus 201 has a solid image portion in the tenth embodiment, and the stencil printing apparatus 201 has a solid image portion with small size paper. The second double-sided printing operation is the same as the second double-sided printing operation when the stencil printing apparatus 201 has a solid image portion in the tenth embodiment, and the third stencil printing apparatus 201 has a solid image portion with small size paper. The double-sided printing operation is the same as the third double-sided printing operation in the tenth embodiment when the stencil printing apparatus 201 has a solid image portion.

  Next, a case where the paper P is a large size paper will be described. When the plate making start key is pressed, each image image is read in the image reading unit 207, and each read image passes through the lens 248, the image sensor 249, and an A / D converter (not shown) and then the document. Two image data signals are stored in the image memory 214, respectively. When this large size sheet is used, the control unit 340 does not determine whether a solid image portion exists in the document image.

  The position where the air ejection from the first peeling member 210 to the surface-printed paper PA and the air ejection from the second peeling member 211 to the printed paper PB correspond to the front end of the paper and the length in the conveyance direction of the paper is almost the middle. A double-sided printing operation program for a large-size sheet, which is performed at a position corresponding to the position, is read. The operation of the stencil printing apparatus 201 in this case is the same as the double-sided printing operation of the stencil printing apparatus 201 when using large-size paper in the eighth embodiment.

  According to the configuration described above, the same operational effects as those of the tenth embodiment can be obtained when small-size paper is used, and the same operational effects as those of the eighth embodiment can be obtained when large-size paper is used.

  In the present embodiment, the second piston 268 reciprocates once in the second cylinder 267 during one rotation of the plate cylinder 212 during single-sided printing of a document that does not have a solid image portion when using small-size paper. When a small-size sheet is used and a document having no solid image portion is printed on both sides, the first piston 254 reciprocates once in the first cylinder 253 during one rotation of the plate cylinder 212 and the second piston 268 moves. The second piston 268 is reciprocated once in the second cylinder 267, during one rotation of the plate cylinder 212 during single-sided printing of a document having a solid image portion when using small-size paper and when using large-size paper. Is moved back and forth in the second cylinder 267, and 1 of the plate cylinder 212 is used at the time of double-sided printing of a document having a solid image portion when using small-size paper and when using large-size paper. The first piston 254 second piston 268 with the interior of the first cylinder 253 2 reciprocates adopts a configuration in which the inside of the second cylinder 267 reciprocates twice during rolling.

  Here, since the rotational peripheral speed of the plate cylinder 212 can be changed according to the printing speed, the time during which the plate cylinder 212 makes one rotation also changes according to the printing speed. For this reason, in this embodiment, the rotational peripheral speeds of the piston drive motors 260 and 274 are such that the reciprocating speed of the pistons 254 and 268 is a constant speed that is twice or more the maximum rotational peripheral speed of the plate cylinder 212. Is controlled to rotate intermittently at a constant speed.

  It should be noted that the rotational peripheral speeds of the piston drive motors 260 and 274 may be changed according to the rotational peripheral speed of the plate cylinder 212. In this case, the moving speed of the pistons 254 and 268 is also reduced, and the jet pressure of air from the openings 210c and 211c may be reduced to prevent good printing. In such a case, it is necessary to increase the rotational peripheral speeds of the piston drive motors 260 and 274 as appropriate so as to keep the air ejection pressure from the openings 210c and 211c above a certain value.

  Next, a thirteenth embodiment of the present invention is described. The thirteenth embodiment is different from the above-described twelfth embodiment only in that each air supply means 283, 311 is used instead of each air supply means 252, 266, and other configurations are different. Are the same. The operation of the stencil printing apparatus 201 in the thirteenth embodiment will be described below. First, a case where single-sided printing is set on the operation panel 281 will be described.

  After placing the document to be printed on the contact glass 241, the operator sets the plate making conditions using various keys on the operation panel 281 and presses the plate making start key. When the plate making start key is pressed, the control means 340 confirms the size of the paper P loaded on the paper feed tray 229 based on the paper size detection signal from the paper size detection sensor 234. First, a case where the paper P is a small size paper will be described.

  When the plate making start key is pressed, the image reading unit 207 performs a document image reading operation, and the read image passes through the lens 248, the image sensor 249, and an A / D converter (not shown), and then one original document. Is stored in the image memory 214 as an image data signal. When the image data signal for one document is stored in the image memory 214, the control unit 340 determines whether or not a solid image portion exists in the document image, as in the twelfth embodiment.

  In this determination, if it is determined that the original image has no solid image portion, the small-size paper solid image in which the ejection of air from the second peeling member 211 to the printed paper PB is performed only at the position corresponding to the front end portion of the paper. When the one-side printing operation program for no part is read and it is determined that the original image has a solid image portion, the position and solidity corresponding to the leading edge of the paper from the second peeling member 211 to the printed paper PB. A single-sided printing operation program for reading a small-size sheet solid image portion, which is performed at a position corresponding to the image portion, is read.

  The single-sided printing operation of the stencil printing apparatus 201 when there is no small-size paper solid image part is the same as the single-sided printing operation of the stencil printing apparatus 201 when the small-size paper is used in the ninth embodiment. The single-sided printing operation of the stencil printing apparatus 201 in the case of presence is the same as the single-sided printing operation of the stencil printing apparatus 201 in the case of the presence of the solid image portion in the eleventh embodiment.

  Next, a case where the paper P is a large size paper will be described. When the plate making start key is pressed, the image reading unit 207 performs a document image reading operation, and the read image passes through the lens 248, the image sensor 249, and an A / D converter (not shown), and then one original document. Is stored in the image memory 214 as an image data signal. When this large size sheet is used, the control unit 340 does not determine whether a solid image portion exists in the document image.

  For large-sized paper, the ejection of air from the second peeling member 211 to the printed paper PB is performed at a position corresponding to the front end of the paper and a position substantially corresponding to the middle of the length of the printed paper PB in the paper conveyance direction. The single-sided printing operation program is read. The operation of the stencil printing apparatus 201 in this case is the same as the single-sided printing operation of the stencil printing apparatus 201 when using large-size paper in the ninth embodiment.

  Next, a case where duplex printing is set on the operation panel 281 will be described. As in the twelfth embodiment, the operator presses the plate making start key after placing the first document on the contact glass 241. When the plate making start key is pressed, the control means 340 confirms the size of the paper P stacked on the paper feed tray 229. First, a case where the paper P is a small size paper will be described.

  When the plate making start key is pressed after the first document is set on the contact glass 241, the image reading unit 207 performs a reading operation, and the read image is stored in the image memory 214. Stored as a data signal. Thereafter, when the second original is set on the contact glass 241 and the pressure plate 242 is closed, the reading operation is performed in the same manner, and the read image is stored in the image memory 214 as the second image data signal. Is done.

  When the image data signals for the two originals are stored in the image memory 214, the control unit 340 determines whether there is a solid image portion in the original image. At this time, if it is determined that there is no solid image portion in each original image, the small size paper solid is produced in which the ejection of air from the first peeling member 210 and the second peeling member 211 is performed only at the position corresponding to the leading edge of the paper. When the double-sided printing operation program for no image portion is read and it is determined that the original image serving as the first plate-making image has a solid image portion, the ejection of air from the first peeling member 210 corresponds to the leading edge portion of the paper. The first double-sided printing operation program for the presence of the small-size paper solid image portion, which is performed at the position corresponding to the solid image portion and the position where the air is ejected from the second peeling member 211 only at the position corresponding to the front end portion of the paper. Is read, and it is determined that there is a solid image portion only on the original image to be the second plate-making image, the blowout of air from the first peeling member 210 corresponds to the leading edge portion of the paper. The second double-sided printing operation program for reading a small-size paper solid image portion is read, which is performed only at the position and the air blowing from the second peeling member 211 is performed at a position corresponding to the front end portion of the paper and a position corresponding to the solid image portion. If it is determined that each original image has a solid image portion, the ejection of air from the first peeling member 210 and the second peeling member 211 is at a position corresponding to the front end portion of the sheet and a position corresponding to the solid image portion. The third double-sided printing operation program for the presence of the small-size sheet solid image portion to be performed is read.

  The double-sided printing operation of the stencil printing apparatus 201 when there is no small-size paper solid image part is the same as the double-sided printing operation of the stencil printing apparatus 201 in the seventh embodiment, and the stencil printing apparatus when there is a small-size paper solid image part The first double-sided printing operation 201 is the same as the first double-sided printing operation when the stencil printing apparatus 201 has a solid image portion in the eleventh embodiment, and the stencil printing apparatus 201 has a solid image portion with small size paper. The second double-sided printing operation is the same as the second double-sided printing operation when the stencil printing apparatus 201 has a solid image portion in the eleventh embodiment, and the third stencil printing apparatus 201 has a solid image portion with small size paper. The double-sided printing operation is the same as the third double-sided printing operation in the eleventh embodiment when the stencil printing apparatus 201 has a solid image portion.

  Next, a case where the paper P is a large size paper will be described. When the plate making start key is pressed, each image image is read in the image reading unit 207, and each read image passes through the lens 248, the image sensor 249, and an A / D converter (not shown) and then the document. Two image data signals are stored in the image memory 214, respectively. When this large size sheet is used, the control unit 340 does not determine whether a solid image portion exists in the document image.

  The position where the air ejection from the first peeling member 210 to the surface-printed paper PA and the air ejection from the second peeling member 211 to the printed paper PB correspond to the front end of the paper and the length in the conveyance direction of the paper is almost the middle. A double-sided printing operation program for a large-size sheet, which is performed at a position corresponding to the position, is read. The operation of the stencil printing apparatus 201 in this case is the same as the double-sided printing operation of the stencil printing apparatus 201 when using large-size paper in the ninth embodiment.

  According to the configuration described above, the same operational effects as those of the eleventh embodiment can be obtained when small-size paper is used, and the same operational effects as those of the ninth embodiment can be obtained when large-size paper is used.

  In the present embodiment, when small-size paper is used and a single-sided printing of a document having no solid image portion is performed, one of the pistons 313 and 319 corresponds to one of the pistons 313 and 319 during one rotation of the plate cylinder 212. One of the pistons 285 and 291 is rotated during one rotation of the plate cylinder 212 when two-sided printing of a document which reciprocates once within the 312 and 318 and uses a small size paper and does not have a solid image portion. Reciprocates once in the corresponding cylinders 284 and 290, and one of the pistons 313 and 319 reciprocates once in the corresponding cylinders 312 and 318, and has a solid image portion when using small size paper. During single-sided printing of a document or when using large-size paper, the pistons 313 and 319 move through the corresponding cylinders 312 and 318 during one rotation of the plate cylinder 212. Each of the pistons 285 and 291 corresponds to one rotation of the plate cylinder 212 during both-side printing of a document having a solid image portion when reciprocating once and using a small-size sheet and when using a large-size sheet. A configuration is adopted in which the pistons 313 and 319 reciprocate once in the corresponding cylinders 312.318 respectively in the cylinders 284 and 290.

  Also in this embodiment, since the rotational peripheral speed of the plate cylinder 212 can be changed according to the printing speed, the time during which the plate cylinder 212 makes one revolution also changes according to the printing speed. For this reason, in this embodiment, the piston drive motors 299, 302, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, 327, Control is performed so that the rotational circumferential speed of 330 is intermittently driven at a constant speed.

  It should be noted that the rotational peripheral speeds of the piston drive motors 299, 302, 327, and 330 may be changed according to the rotational peripheral speed of the plate cylinder 212. During the low-speed rotation, the moving speeds of the pistons 285, 291, 313 and 319 are also reduced, and the jet pressure of air from the openings 210c and 211c may be reduced, and good printing may not be performed. In such a case, it is necessary to increase the rotational peripheral speeds of the piston drive motors 299, 302, 327, and 330 as appropriate, and to maintain the air ejection pressure from the openings 210c and 211c at a certain value or more.

  In the twelfth and thirteenth embodiments described above, the first piston 254 is driven by the first piston drive motor 260, the second piston 268 is driven by the second piston drive motor 274, and the first piston 285 is driven by the first piston drive motor 299. The second piston 313 is reciprocated by the second piston drive motor 327, the third piston 291 is reciprocated by the third piston drive motor 302, and the fourth piston 319 is reciprocated by the fourth piston drive motor 330. Without using the drive motors 260, 274, 299, 327, 302, and 330, the rotational drive force from the plate cylinder drive means (not shown) is transmitted by drive force transmission means such as gears and belts, and the pistons 254, 268, 285, respectively. It may be configured to reciprocate 313,291,319 .

  When this configuration is adopted in the twelfth embodiment, the second piston 268 is moved during one rotation of the plate cylinder when a small-size sheet is used and a single-sided printing of a document having no solid image portion is performed. When double-sided printing of a document that has size paper and does not have a solid image portion, the first piston 254 and the second piston 268 are reciprocated once during each rotation of the plate cylinder, so that one side when a large size paper is used The second piston 268 is rotated during one rotation of the plate cylinder during single-sided printing of a document having a solid image portion during printing, and one rotation of the plate cylinder during double-sided printing when using a large size paper and double-sided printing of a document having a solid image portion. Since the first piston 254 and the second piston 268 need to be reciprocated twice, the driving force transmitting means transmits the rotational driving force for one rotation of the plate cylinder as the driving force for one reciprocation of the piston. Constitute two paths with accelerating and while path for transmitting a driving force of the route and the piston 2 reciprocating component, it is necessary to adopt a configuration for switching the driving force transmission path by the switching means.

  In both the twelfth and thirteenth embodiments, when a small-size sheet is used and a document having a solid image portion is used, the paper P is located at a position corresponding to the solid image portion of the sheet P, and when a large-size sheet is used. Therefore, it is necessary to change the air ejection location according to the position of the solid image portion and the length of the paper P in the paper conveyance direction. In this case, it is necessary to control the reciprocation of the pistons 254, 268, 285, 313, 291 and 319 by using connecting means such as a clutch for connecting or disconnecting the driving force as the driving force transmitting means.

1 is a schematic front view of a stencil printing apparatus to which the first and second embodiments of the present invention can be applied. It is a schematic perspective view which shows the plate cylinder drive means used for each 1st thru | or 6th embodiment of this invention. It is the schematic which shows the air supply means used for each 1st, 3rd, 5th embodiment of this invention. It is the schematic explaining the piston drive means used for each 1st, 3rd, 5th embodiment of this invention. It is a block diagram of the control means used for the 1st and 2nd embodiment of the present invention. It is the schematic which shows the air supply means used for each 2nd, 4th, 6th embodiment of this invention. It is the schematic explaining the piston drive means used for each 2nd, 4th, 6th embodiment of this invention. It is a schematic front view of the stencil printing apparatus which can apply the 3rd and 4th embodiment of this invention. It is a block diagram of the control means used for the 3rd and 4th embodiment of the present invention. It is a schematic front view of the stencil printing apparatus which can apply 5th and 6th embodiment of this invention. It is a block diagram of the control means used for the 5th and 6th embodiment of this invention. It is a schematic front view of a stencil printing apparatus to which the seventh to thirteenth embodiments of the present invention can be applied. It is the schematic which shows the 1st air supply means used for each 7th, 8th, 10th, 12th embodiment of this invention. It is the schematic explaining the 1st piston drive means used for each of the 7th, 8th, 10th and 12th embodiments of the present invention. It is the schematic which shows the 2nd air supply means used for each 7th, 8th, 10th, 12th embodiment of this invention. It is the schematic explaining the 2nd piston drive means used for each 7th, 8th, 10th, 12th embodiment of this invention. It is a block diagram of the control means used for the 7th Embodiment of this invention. It is a block diagram of the control means used for the 8th and 9th embodiment of this invention. It is the schematic which shows the 1st air supply means used for each 9th, 11th, and 13th embodiment of this invention. It is the schematic explaining the 1st piston drive means and the 3rd piston drive means used for each 9th, 11th, and 13th embodiment of the present invention. It is the schematic which shows the 2nd air supply means used for each 9th, 11th, 13th embodiment of this invention. It is the schematic explaining the 2nd piston drive means and 4th piston drive means used for each 9th, 11th, and 13th embodiment of this invention. It is a block diagram of the control means used for the 10th and 11th embodiment of this invention. It is a block diagram of the control means used for the 12th and 13th embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,104,107,201 Stencil printing apparatus 2,202 Printing part 4,204 Paper feeding part 6,206 Paper discharge part 9,212 Plate cylinder 11,213 Pressing means (press roller)
47 Peeling member 47c Spout (opening)
48 Air supply means 49 Cylinder 50 Piston 52 Rotating plate 56 Rotating plate position detecting means (Rotating plate position detecting sensor)
57 Piston drive means 69 Plate cylinder angle detection means (pulse detection sensor)
71 Drive motor (piston drive motor)
74, 106, 106, 108, 282, 339, 340 Control means 77, 253, 284 First cylinder 78, 254, 285 First piston 81, 256, 288 First rotary plate 83, 267, 312 Second cylinder 84, 268,313 Second piston 86,270,316 Second rotating plate 92,260,299 Drive motor (first piston drive motor)
95,274,327 drive motor (second piston drive motor)
100,264,307 Rotating plate position detecting means (first rotating plate position detecting sensor)
101,278,335 Rotating plate position detecting means (second rotating plate position detecting sensor)
102, 265, 309 First piston driving means 103, 279, 337 Second piston driving means 208 Auxiliary tray 209 Refeeding means 210 First peeling member 210c First outlet (opening)
211 2nd peeling member 211c 2nd jet nozzle (opening)
252 and 283 First air supply means 266 and 311 Second air supply means 290 Third cylinder 291 Third piston 293 Third rotary plate 302 Drive motor (third piston drive motor)
308 Rotating plate position detecting means (third rotating plate position detecting sensor)
310 third piston driving means 318 fourth cylinder 319 fourth piston 321 fourth rotating plate 330 driving motor (fourth piston driving motor)
336 Rotating plate position detecting means (fourth rotating plate position detecting sensor)
338 Fourth piston driving means P paper PA front surface printed paper PB printed paper

Claims (6)

A printing unit having a pressing means to press the sheet against the plate cylinder and the plate cylinder, a sheet feeding unit for feeding toward the sheet to the printing unit, a printed paper on which printing has been made in the printing unit In a stencil printing apparatus having a paper discharge unit for discharging,
A peeling member having a spout for ejecting air between the outer peripheral surface and the paper so as to peel the paper pressed on the outer peripheral surface of the plate cylinder by the pressing means from the outer peripheral surface of the plate cylinder; And an air supply means for supplying air to the peeling member, wherein the peeling member is located at a first position corresponding to the leading edge of the paper, and downstream of the first position of the paper in the paper transport direction. to second jettable der air from the ejection port at the position is, if the sheet length in the conveying direction of the sheet is larger than the predetermined value, the release member is a sheet of the paper and the first position When the air is ejected from the ejection port at both the second position, which is substantially the middle of the transport direction length, and the length of the paper in the transport direction is equal to or less than a predetermined value, the peeling member is ejecting air from the spout only at the first position Stencil printing machine according to claim and. A printing unit having a plate cylinder and a pressing unit that presses the sheet against the plate cylinder, a sheet feeding unit that feeds the sheet toward the printing unit, and a printed sheet that has been printed by the printing unit is discharged. A stencil printing machine having a paper discharge unit for
A peeling member having a spout for ejecting air between the outer peripheral surface and the paper so as to peel the paper pressed on the outer peripheral surface of the plate cylinder by the pressing means from the outer peripheral surface of the plate cylinder; And an air supply means for supplying air to the peeling member, wherein the peeling member is located at a first position corresponding to the leading edge of the paper, and downstream of the first position of the paper in the paper transport direction. Air can be ejected from the ejection port at the second position where the print image formed on the sheet has a solid image portion, the peeling member has the first position and the solid image portion. And the second position, which is a corresponding position, and when the print image does not have a solid image portion , the peeling member is only in the first position. It is characterized by ejecting air from the spout That the stencil printing machine. A printing unit having a plate cylinder and a pressing unit that presses the sheet against the plate cylinder, a sheet feeding unit that feeds the sheet toward the printing unit, and a printed sheet that has been printed by the printing unit is discharged. A stencil printing machine having a paper discharge unit for
A peeling member having a spout for ejecting air between the outer peripheral surface and the paper so as to peel the paper pressed on the outer peripheral surface of the plate cylinder by the pressing means from the outer peripheral surface of the plate cylinder; And an air supply means for supplying air to the peeling member, wherein the peeling member is located at a first position corresponding to the leading edge of the paper, and downstream of the first position of the paper in the paper transport direction. When the air can be ejected from the ejection port at the second position where the paper is transported and the length of the paper in the paper transport direction is greater than a predetermined value, the peeling member is transported from the first position to the paper. Air is ejected from the jet outlet at both the second position, which is the middle position in the direction length, and the length of the paper in the paper transport direction is less than a predetermined value and formed on the paper. When the printed image has a solid image part, the peeling Material is ejected air from the jetting port in both the second position the corresponding to the solid image portion and the first position, the printed image paper transport direction length of the sheet is equal to or lower than a predetermined value The stencil printing apparatus according to claim 1, wherein when the solid image portion is not provided, the peeling member ejects air from the ejection port only at the first position. A printing unit having a plate cylinder and a pressing unit that presses the sheet against the plate cylinder, a sheet feeding unit that feeds the sheet toward the printing unit, and a printed sheet that has been printed by the printing unit is discharged. A paper discharge unit that performs the duplex printing, an auxiliary tray that temporarily stores printed paper on the surface of which the printed image is formed during duplex printing, and the surface printing that is stored on the auxiliary tray during duplex printing. A paper refeeding unit that refeeds the printed paper toward the printing unit, and the front-side printed paper that has passed through the printing unit during duplex printing is peeled off from the outer peripheral surface of the plate cylinder and guided to the auxiliary tray. A first peeling member; and a second peeling member that peels the printed paper that has passed through the printing unit from the outer peripheral surface of the plate cylinder and guides it to the paper discharge unit. The first corresponding to the surface image in the direction A divided master-making master having a plate-making image and a second master-making image corresponding to the back-side image is wound on the plate cylinder with a master-making master on which a third plate-making image for single-sided printing is formed during single-sided printing. In a stencil printing apparatus capable of switching between printing and duplex printing ,
The first peeling member has a first jet outlet that blows air between the outer peripheral surface and the surface printed paper so as to peel the surface printed paper from the outer peripheral surface of the plate cylinder during double-sided printing. The second peeling member has a second jet nozzle for ejecting air between the outer peripheral surface and the printed paper so as to peel the printed paper from the outer peripheral surface during double-sided printing and single-sided printing. And an air supply means for supplying air to the first peeling member and the second peeling member, wherein the first peeling member is at the first position corresponding to the front end of the surface printed paper, and the second peeling member is printed. Air is ejected from each of the ejection ports at a second position corresponding to the leading edge of the paper, and the first peeling member is located downstream of the first position of the surface-printed paper in the paper transport direction. In position, the second peeling part Is capable of ejecting air from each of the jet outlets at a fourth position located downstream of the second position of the printed paper in the paper transport direction, and the length of the paper in the paper transport direction during single-sided printing. If it is larger than the predetermined value, the second peeling member draws air from the second outlet at both the second position and the fourth position, which is approximately the middle of the length of the paper in the paper transport direction. If the length of the paper in the paper transport direction is less than a predetermined value during jetting or single-sided printing, the second peeling member jets air from the second jetting port only at the second position, When the sheet conveyance direction length is larger than the predetermined value, the first peeling member is the first position at both the first position and the third position, which is approximately the middle of the sheet conveyance direction length. Air is ejected from one ejection port and the second peeling member Air is ejected from the second outlet at both the second position and the fourth position, which is approximately the middle of the length of the paper in the paper conveyance direction, and the length of the paper in the paper conveyance direction during duplex printing. Is less than or equal to a predetermined value, the first peeling member jets air from the first jet only at the first position, and the second peeling member jets air from the second jet only at the second position. A stencil printing apparatus characterized by that. A printing unit having a plate cylinder and a pressing unit that presses the sheet against the plate cylinder, a sheet feeding unit that feeds the sheet toward the printing unit, and a printed sheet that has been printed by the printing unit is discharged. A paper discharge unit that performs the duplex printing, an auxiliary tray that temporarily stores printed paper on the surface of which the printed image is formed during duplex printing, and the surface printing that is stored on the auxiliary tray during duplex printing. A paper refeeding unit that refeeds the printed paper toward the printing unit, and the front-side printed paper that has passed through the printing unit during duplex printing is peeled off from the outer peripheral surface of the plate cylinder and guided to the auxiliary tray. A first peeling member; and a second peeling member that peels the printed paper that has passed through the printing unit from the outer peripheral surface of the plate cylinder and guides it to the paper discharge unit. The first corresponding to the surface image in the direction A divided master-making master having a plate-making image and a second master-making image corresponding to the back-side image is wound on the plate cylinder with a master-making master on which a third plate-making image for single-sided printing is formed during single-sided printing. In a stencil printing apparatus capable of switching between printing and duplex printing ,
The first peeling member has a first jet outlet that blows air between the outer peripheral surface and the surface printed paper so as to peel the surface printed paper from the outer peripheral surface of the plate cylinder during double-sided printing. The second peeling member has a second jet nozzle for ejecting air between the outer peripheral surface and the printed paper so as to peel the printed paper from the outer peripheral surface during double-sided printing and single-sided printing. And an air supply means for supplying air to the first peeling member and the second peeling member, wherein the first peeling member is at the first position corresponding to the front end of the surface printed paper, and the second peeling member is printed. Air is ejected from each of the ejection ports at a second position corresponding to the leading edge of the paper, and the first peeling member is located downstream of the first position of the surface-printed paper in the paper transport direction. In position, the second peeling part Is capable of ejecting air from the respective jet outlets at a fourth position located downstream of the second position of the printed paper in the paper transport direction, and is formed on the paper during single-sided printing. When the third print image corresponding to the plate-making image has a solid image portion, the second peeling member has the second jet at both the second position and the fourth position corresponding to the solid image portion. When the third printing image does not have a solid image portion during single-sided printing, air is ejected from the outlet, and the second peeling member ejects air from the second outlet only at the second position to perform double-sided printing. When the first print image corresponding to the first plate-making image formed on the paper and the second print image corresponding to the second plate-making image sometimes have a solid image portion, the first peeling member is At a position corresponding to the first position and the solid image portion Air is ejected from the first jet outlet at both the third position and the second peeling member is at the second jet at both the second position and the fourth position corresponding to the solid image portion. When air is blown out from the outlet and the first print image has a solid image portion and the second print image does not have a solid image portion during double-sided printing, the first peeling member has the first position and the solid image. At both the image position and the third position corresponding to the image portion, air is ejected from the first ejection port, and the second peeling member ejects air from the second ejection port only at the second position. When the first print image does not have a solid image portion and the second print image has a solid image portion, the first peeling member ejects air from the first ejection port only at the first position. And the second peeling member corresponds to the second position and the solid image portion. When both the first and second print images have no solid image part during double-sided printing, air is ejected from the second jet outlet at both the fourth position and the first position. The stencil printing apparatus, wherein the member ejects air from the first ejection port only at the first position, and the second peeling member ejects air from the second ejection port only at the second position . A printing unit having a plate cylinder and a pressing unit that presses the sheet against the plate cylinder, a sheet feeding unit that feeds the sheet toward the printing unit, and a printed sheet that has been printed by the printing unit is discharged. A paper discharge unit that performs the duplex printing, an auxiliary tray that temporarily stores printed paper on the surface of which the printed image is formed during duplex printing, and the surface printing that is stored on the auxiliary tray during duplex printing. A paper refeeding unit that refeeds the printed paper toward the printing unit, and the front-side printed paper that has passed through the printing unit during duplex printing is peeled off from the outer peripheral surface of the plate cylinder and guided to the auxiliary tray. A first peeling member; and a second peeling member that peels the printed paper that has passed through the printing unit from the outer peripheral surface of the plate cylinder and guides it to the paper discharge unit. The first corresponding to the surface image in the direction A divided master-making master having a plate-making image and a second master-making image corresponding to the back-side image is wound on the plate cylinder with a master-making master on which a third plate-making image for single-sided printing is formed during single-sided printing. In a stencil printing apparatus capable of switching between printing and duplex printing ,
The first peeling member has a first jet outlet that blows air between the outer peripheral surface and the surface printed paper so as to peel the surface printed paper from the outer peripheral surface of the plate cylinder during double-sided printing. The second peeling member has a second jet nozzle for ejecting air between the outer peripheral surface and the printed paper so as to peel the printed paper from the outer peripheral surface during double-sided printing and single-sided printing. And an air supply means for supplying air to the first peeling member and the second peeling member, wherein the first peeling member is at the first position corresponding to the front end of the surface printed paper, and the second peeling member is printed. Air is ejected from each of the ejection ports at a second position corresponding to the leading edge of the paper, and the first peeling member is located downstream of the first position of the surface-printed paper in the paper transport direction. In position, the second peeling part Is capable of ejecting air from each of the jet outlets at a fourth position located downstream of the second position of the printed paper in the paper transport direction, and the length of the paper in the paper transport direction during single-sided printing. If it is larger than the predetermined value, the second peeling member draws air from the second outlet at both the second position and the fourth position, which is approximately the middle of the length of the paper in the paper transport direction. When the length of the paper in the paper conveyance direction is less than a predetermined value during ejection and single-sided printing, and the third print image corresponding to the third plate-making image formed on the paper has a solid image portion The second peeling member ejects air from the second ejection port at both the second position and the fourth position corresponding to the solid image portion, and the length of the sheet in the sheet conveyance direction is a predetermined value during single-sided printing. In the following cases, the third print image is solid When the second peeling member ejects air from the second ejection port only at the second position, and the length of the paper in the paper conveyance direction is larger than a predetermined value during duplex printing, The first peeling member ejects air from the first outlet at both the first position and the third position, which is approximately the middle of the length of the paper in the paper conveyance direction, and the second peeling member Air is ejected from the second outlet at both the second position and the fourth position, which is approximately the middle of the length of the paper in the paper conveyance direction, and the length of the paper in the paper conveyance direction during duplex printing. In which the first print image corresponding to the first plate-making image formed on the sheet and the second print image corresponding to the second plate-making image both have a solid image portion. The first peeling member has a position corresponding to the first position and the solid image portion. Air is ejected from the first jet outlet at both the third position and the second peeling member is at the second position and the fourth position, which is a position corresponding to the solid image portion. When air is blown from two jet nozzles and the length of the paper in the paper transport direction is less than a predetermined value during double-sided printing, the first print image has a solid image portion and the second print image has a solid image portion. If not, the first peeling member ejects air from the first outlet at both the first position and the third position corresponding to the solid image portion, and the second peeling member Air is ejected from the second outlet only at the second position, and the length of the paper in the paper transport direction is less than or equal to a predetermined value during duplex printing, and the first print image does not have a solid image portion. When the second print image has a solid image portion, the first peeling portion Ejects air from the first jet only at the first position and the second peeling member from the second jet at both the second position and the fourth position corresponding to the solid image portion. When the air is blown and the length of the paper in the paper transport direction is less than or equal to a predetermined value at the time of double-side printing, the first print image and the second print image both have no solid image portion. The stencil printing apparatus, wherein the peeling member jets air from the first jet port only at the first position, and the second peeling member jets air from the second jet port only at the second position .

Images