JP2011073398A - Double-side printing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To standardize the delivery control of papers from a storage section regardless of the paper sizes in a double-side printing machine equipped with a storage section. <P>SOLUTION: In a double-side printing machine which has the first printing section 3 which prints on one surface of a paper P1, a storage section 5 in which a paper P2 with one surface printed is sent and then the sent-in paper P2 is stored, and the second printing section 7 which prints on the other surface of the paper P2 sent from this storage section 5, the size information SI of the paper P1 is acquired. The storage section 5 sequentially holds the lower end part P2L of the paper P2 sent in one by one to the sent-in position and then moves each paper P2 to the delivery position within the storage section 5 with each of the lower end part P2L apart with the predetermined space from each other. Based on the size information SI, the storage section changes the vertical directional holding position of the lower end part P2L of the paper P2 so that the upper end position of the printing paper P2 at the delivery position becomes the predetermined height position. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a duplex printing apparatus that performs printing on one side and the other side of a sheet. More specifically, the present invention relates to a double-sided printing apparatus that stores paper printed on one side for a predetermined time and prints it on the other side.

  In recent years, from the viewpoint of environmental problems and the like, it has been desired to reduce the amount of paper used for printing, and double-sided printing that performs printing on one side and the other side of paper is popular. As an example of this double-sided printing apparatus, a cylindrical first drum and a second drum each having a base paper wound around an outer peripheral surface are disposed adjacent to each other, and printing is performed on one surface of the paper with the first drum. 2. Description of the Related Art A double-sided stencil printing apparatus that conveys paper and prints on the other side of the paper with a second drum is known.

  In the case of such a double-sided printing apparatus, there is a possibility that the paper is soiled by carrying for other-side printing or performing other-side printing before the ink printed on one side is sufficiently dried.

  In Patent Document 1, the first sheet is printed on the first drum and printed on one side of the sheet. The sheet on which the one side is printed is secondarily fed to the storage unit and stored for a predetermined time, and then conveyed to the first drum. A double-sided printing apparatus that performs tertiary paper feeding to two drums has been proposed.

JP-A-2005-29375

  As such a storage unit, the paper that has been secondarily fed is sequentially carried to the carry-in position in the storage unit, moved to a carry-out position in the storage unit with a predetermined interval after the carry-in, and the paper is dried during this movement time. Thus, a storage unit for carrying out the dried paper at the carry-out position in accordance with the timing of the third paper feed at which the second drum is at a predetermined position can be considered.

  However, when such a storage unit corresponds to various paper sizes, since the distance between the upper end of the paper at the carry-out position and the second drum is different, control for carrying out the paper in accordance with the timing of the third paper feeding is performed. It will be different for each paper size. That is, it is necessary to change the control for the storage unit to carry out the paper according to the paper size, and the control may be complicated. Such control for carrying out the paper may become particularly difficult as the printing speed increases.

  SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a double-sided printing apparatus that unifies paper carry-out control from a storage unit regardless of paper size.

  In order to solve the above-described problem, a duplex printing apparatus of the present invention includes a first printing unit that prints on one side of a sheet, a storage unit that receives a sheet on which one side is printed, and stores the loaded sheet, A double-sided printing apparatus comprising a second printing unit that prints on the other side of the paper unloaded from the storage unit, comprising an information acquisition means for acquiring size information of the paper, the storage unit being carried into the storage unit A holding movement that sequentially holds the lower end portion of the paper that is sequentially carried into the position, and sequentially moves the paper holding the lower end portion toward the carry-out position in the storage portion with the lower end portions having a predetermined gap therebetween. And a position changing means for changing the vertical position of the holding and moving means so that the upper end position of the paper at the carry-out position becomes a predetermined height position based on the size information. To do.

  Here, the “carry-in position” means a lower position in the storage unit 5 where the carried-in paper can move. The “size information” means information indicating the size of the paper, and is not limited to a specific size, but may be format information defined by an industrial standard such as JIS or ISO. The “lower end” means a portion in the vicinity of the lower end of the paper, specifically, a portion from the lower end to the upper end in a direction of about 30% of the total length of the paper.

  In the double-sided printing apparatus of the present invention, the storage unit separates the carry-in surface on which the paper carried into the carry-in position moves and the upper end of the paper carried into the carry-in position from the carry-in surface, There may be provided a peeling means for restricting so as not to return to the carry-in surface again.

  Here, the “upper end portion” means a portion in the vicinity of the upper end of the sheet, specifically, a portion from the upper end to the lower end direction to a position of about 30% of the total length of the sheet. The above-mentioned “does not return to the carry-in surface” is not limited to the case where the entire peeled upper end portion does not return to the carry-in surface again, and a part of the peeled upper end portion is again on the carry-in surface. It means that the case of not returning to is included.

  According to the double-sided printing device of the present invention, the first printing unit that prints on one side of the paper, the paper on which one side is printed, the storage unit that stores the paper that has been carried in, and the storage unit A second printing unit that prints on the other side of the paper, and the storage unit sequentially holds the lower end portion of the paper sequentially carried into the carry-in position in the storage unit, and each of the papers holding the lower end portion thereof. Based on the size information, the holding and moving means that sequentially moves toward the carry-out position in the storage unit with the lower ends of the paper being spaced apart from each other so that the upper end position of the paper at the carry-out position is a predetermined height position. In addition, since the position changing means for changing the vertical position of the holding and moving means is provided, the distance between the upper end of the paper at the carry-in position and the second drum changes even when the paper size is different. Not in the loading position. It is possible to share the control for unloading the sheets, it can be avoided that the control is complicated.

Configuration diagram of duplex printer Configuration diagram of reservoir (part 1) Partial perspective view of reservoir Configuration diagram of reservoir (Part 2) Configuration diagram of peeling means The figure which shows series operation | movement of a peeling means (the 1) The figure which shows series operation | movement of a peeling means (the 2) The figure which shows a series of operation | movement of a peeling means (the 3) The figure which shows series operation | movement of a peeling means (the 4)

  Hereinafter, embodiments of the duplex printing apparatus of the present invention will be described in detail with reference to the drawings. FIG. 1 is a configuration diagram of a duplex printing apparatus 1 that is an embodiment of the duplex printing apparatus of the present invention.

  The double-sided printing apparatus 1 is a double-sided stencil printing apparatus, which feeds an unprinted paper P1 and prints it on one side, stores the paper P2 after the single-sided printing for a predetermined time, and re-feeds the paper P2 to the other side. And the paper P3 after the other side printing is discharged.

  The duplex printing apparatus 1 includes a paper feeding unit 2 that feeds unprinted paper P1, a first printing unit 3 that prints on one side of the paper P1 fed from the paper feeding unit 2, and the first printing unit. 3, the reversing unit 4 that reverses the paper P2 printed on one side, the storage unit 5 that stores the reversed paper P2 for a predetermined time, and the refeed that refeeds the paper P2 stored in the storage unit 5 The paper unit 6, the second printing unit 7 that prints on the other side of the paper P <b> 2 re-feeded from the re-feeding unit 6, and the paper P <b> 3 printed on the other side by the second printing unit 7 are discharged. And a paper discharge unit 8 that performs the above operation.

  The paper feeding unit 2 feeds unprinted paper P1 to the first printing unit 3.

  The configuration of the paper feeding unit 2 will be described. The paper feed unit 2 is provided on the side surface of the apparatus main body 11, and includes a paper feed base 21 on which the paper P 1 is stacked, a paper feed roller 22 that takes out the paper P 1 from the paper feed base 21 one by one, and a paper handling roller 23. , And a timing roller pair 24 for feeding the paper P1 to the first printing unit 3.

  The operation of the paper feed unit 2 will be described. The paper feed unit 2 takes out the paper P1 stacked on the paper feed tray 21 by the paper feed roller 22 and the paper rolling roller 23, and sends it to the first printing unit 3 at a predetermined timing by the timing roller pair 24.

  The apparatus main body 11 of the duplex printing apparatus 1 recognizes the paper size of the paper P1 supplied to the paper supply unit 2 and transmits information size information SI to a control unit (not shown) in the apparatus main body 11. Is built-in. This size information SI is information for recognizing the size of the paper P1, is not limited to a specific size, and may be format information defined by an industrial standard such as JIS or ISO. The information acquisition unit 12 may automatically recognize the paper size of the paper P1 supplied to the paper feeding unit 2 and transmit the size information SI, and supplies the paper P1 to the paper feeding unit 2. The operator may recognize the paper size and transmit the size information SI.

  The first printing unit 3 prints on one side of the paper P1.

  The configuration of the first printing unit 3 will be described. The first printing unit 3 includes a first plate cylinder 31. The first plate cylinder 31 has an ink-permeable peripheral wall 31a, and is driven to rotate in the direction of arrow A in the figure by a driving means (not shown).

  Inside the first plate cylinder 31, there are an ink supply roller 32 in contact with the inner peripheral surface of the peripheral wall 31a, a doctor roller 33 for supplying a predetermined amount of ink to the ink supply roller 32, and an ink bottle 34 filled with ink. Is provided.

  A base paper M is wound around the outer peripheral surface of the first plate cylinder 31 by a clamp (not shown). A press roller 35 is provided below the first plate cylinder 31, and the press roller 35 moves in the direction B in the drawing so as to be close to and away from the first plate cylinder 31. Print by pinching with pressure. On the lower right side of the first plate cylinder 31, a separation claw 36 that separates the paper P <b> 2 on which one side is printed by the first printing unit 3 from the base paper M is provided.

  The operation of the first printing unit 3 will be described. When the base paper M is supplied, the first printing unit 3 is wound around the outer peripheral surface of the first plate cylinder 31 as the first plate cylinder 31 rotates, and is held by a clamp (not shown). . Thereafter, the first plate cylinder 31 is driven to rotate at a predetermined peripheral speed, and the press roller 35 is moved to a position where the paper P1 can be pressed with a preset pressing force.

  When the paper P1 is fed from the paper supply unit 2 at a predetermined timing, the paper P1 is nipped and conveyed by the first plate cylinder 31 and the press roller 35, and the paper P1 is pressed onto the base paper M for printing. The paper P2 on which one side is printed is separated from the base paper M by the separation claw 36.

  The reversing unit 4 is for reversing the paper P2 so that one printed surface is on the lower side.

  The configuration of the inverting unit 4 will be described. The reversing unit 4 includes four pulleys 41 arranged along an arcuate locus, a conveyor belt 42 that is stretched around the outer periphery of the four pulleys 41 and moves as the pulleys 41 rotate, An adsorption fan 43 is provided.

  The operation of the inverting unit 4 will be described. The reversing unit 4 sucks the paper P2 printed by the first printing unit 3 by the suction fan 43, and stores the paper P2 on the transport belt 42 along an arcuate path along with the rotation of the pulley 41. Transport to. As the sheet P2 moves along an arcuate path, one side of the printed sheet is positioned downward.

  FIG. 2 is a configuration diagram of the storage unit 5. The storage unit 5 carries the paper P2 printed on one side into the storage unit 5, stores the paper P2 for a predetermined time in order to dry it, and carries it out of the storage unit 5 for refeeding.

  The configuration of the storage unit 5 will be described. As shown in FIG. 2, the storage unit 5 includes a support plate 5a that supports the paper P2 from obliquely below, a side plate 5b that is erected substantially perpendicularly to the support plate 5a on both sides of the support plate 5a, and the support plate 5a. And a cover plate 5c positioned obliquely upward with respect to the plate 5a.

  In addition, the storage unit 5 includes a carry-in surface 5d on which the paper P2 moves on the inner surface of the cover plate 5c and a carry-out surface 5e on which the paper P2 moves on the inner surface of the support plate 5a. Have. The inner surface of the side plate 5b serves as a guide surface that guides the movement of the paper P2 from the carry-in surface 5d to the carry-out surface 5e. Further, the support plate 5a and the cover plate 5c are arranged so that the distance between the upper end of the carry-in surface 5d and the upper end of the carry-out surface 5e is shorter than the distance between the lower end of the carry-in surface 5d and the lower end of the carry-out surface 5d. That is, as shown in FIG. 1 and FIG. 2, the storage part 5 has a fan-shaped outer shape.

  In addition, the storage unit 5 is curved with the first conveying means 51 that moves the paper P2 on the carry-in surface 5d and carries the paper P2 to the carry-in position, and the printed surface with respect to the paper P2 carried to the carry-in position. Based on the size information from the curl application means 52 for applying the curl, the holding movement means 53 for holding the lower end portion P2L of the paper P2 carried to the carry-in position and moving it toward the carry-out surface 5e, and the information acquisition means 12. The position changing unit 54 that changes the vertical position of the holding and moving unit 53 and the upper end P2U of the paper P2 carried to the carry-in position are peeled off, and the upper end P2U is peeled off so as not to return to the carry-in surface 5d again. It comprises means 55 and second transport means 56 for carrying out the paper P2 on the carry-out surface 5e from the storage unit 5.

  Here, the lower end portion P2L of the paper P2 is in the vicinity of the lower end of the paper P2, and specifically means a portion from the lower end to the upper end direction to a position of about 30% of the total length of the paper P2. On the other hand, the upper end portion P2U of the paper P2 is in the vicinity of the upper end of the paper P2, specifically, a portion from the upper end to the lower end direction to a position that is about 30% of the total length of the paper P2.

  The first transport means 51 carries the paper P2 from the reversing unit 4 by moving it on the carry-in surface 5d to the carry-in position in the storage unit 5. Here, the carry-in position is a position below the storage unit 5 where the carried paper P2 can move.

  The structure of the 1st conveyance means 51 is demonstrated. As shown in FIG. 2, the first transport unit 51 includes a housing 511 that is fixed to the cover plate 5 c and is substantially hermetically sealed, a pair of pulleys 512 that are arranged at a predetermined interval in the housing 511, and a pair of pulleys 512. And an annular belt 513 that moves as the pulley 512 is rotated by a driving means (not shown).

  The cover plate 5c is formed with a slot so that the annular belt 513 is exposed, and the pair of pulleys 512 is disposed in the housing 511 so that the surface of the exposed annular belt 513 is substantially flat with the carry-in surface 5d. ing. FIG. 3 is a partial perspective view of the storage unit 5. A plurality of through holes 513a are formed in the annular belt 513 as shown in FIG. Note that FIG. 3 does not show the housing 511 for easy understanding.

  Refer to FIG. 2 again. The first conveying means 51 is disposed outside the housing 511 and the forced peeling claw 514 that can project from the loading surface 5d by rotating around the rotation shaft 514a. The first conveying means 51 discharges the air inside the housing 511 and negatively moves inside the housing 511. An intake fan 515 that is brought into a pressure state, an intake shutter 516 that is provided between the housing 511 and the intake fan 515 and controls intake air by the intake fan 515, and outside air is supplied into the housing 511 that is in a negative pressure state. And an air supply shutter 517 for returning to atmospheric pressure.

  The operation of the first transport means 51 will be described. The intake fan 515 is rotated in advance, the intake shutter 516 is opened at a predetermined timing, the supply shutter 517 is closed, and the air in the housing 511 is discharged to make a negative pressure state. In the housing 511 in a negative pressure state, the air in the reservoir 5 flows into the through hole 513a of the annular belt 513 exposed to the carry-in surface 5d, and a suction force is generated in the through hole 513a.

  The paper P2 carried into the storage unit 5 from the reversing unit 4 is sucked toward the annular belt 513 from the through hole 513a. The driving means (not shown) drives the pulley 512, so that the paper P2 on which one side is printed moves on the exposed annular belt 513 and the substantially flat carry-in surface 5d.

  When the paper P2 is carried to the carry-in position in the storage unit 5, the intake shutter 516 is closed and the air supply shutter 517 is opened, the inside of the housing 511 is returned to atmospheric pressure, and then the forced peeling claw 514 is rotated around the rotation shaft 514a. The paper P2 on the carry-in surface 5d is peeled off by rotating and projecting on the carry-in surface 5d. In the present embodiment, the description will be made assuming that the intake fan 515 is always driven.

  Refer to FIG. 3 again. The curl imparting means 52 imparts curl that curves with one side printed on the paper P <b> 2 sequentially carried into the carry-in position in the storage unit 5 inside.

  The configuration of the curling unit 52 will be described. As shown in FIG. 3, the curling unit 52 includes a fulcrum shaft 521 that is fixed at both ends by mounting plates (not shown) standing on the carry-in surface 5 d on both sides of the first transport unit 51, and the fulcrum shaft 521. A support plate 522 attached to be rotatable in the direction of arrow C around the center, and a guide plate 523 extending in a blade shape obliquely downward from the support plate 522 are provided.

  The operation of the curling means 52 will be described. The curling means 52 includes a support plate 522 and a guide plate that are centered on the fulcrum shaft 521 so that the guide plate 523 faces obliquely downward with respect to the carry-in surface 5d before the paper P2 is carried into the storage unit 5. 523 is rotated.

  As a result, the left and right portions of the paper P2 moved and moved on the carry-in surface 5d move from the carry-in surface 5d onto the guide plate 523, and the left and right portions of the paper P2 move on the carry-in surface 5d. When the sheet P2 moves obliquely below the central portion and is loaded into the loading position, the sheet P2 is given a curl that curves with the printed surface facing inward.

  Since the curl is applied, the paper P2 has a property of being set back to the carry-in surface 5d side even after the paper P2 is seated and peeled off by the first transport means 51.

  Refer to FIG. 2 again. The holding and moving means 53 sequentially holds the lower end portion P2L of the paper P2 carried to the carry-in position, and moves each paper P2 from the carry-in surface 5d side to the carry-out surface 5e side with the lower end portion P2L having a predetermined gap therebetween. It is something to be made. In the present embodiment, description will be made assuming that the carry-in surface 5d side is the moving upstream side and the carry-out surface 5e side is the moving downstream side.

  On the other hand, the upper end portion P2U of the paper P2 moves by free-falling to the carry-out surface 5e side after peeling. As described above, the support plate 5a and the cover plate 5c are arranged so that the distance between the upper end of the carry-in surface 5d and the upper end of the carry-out surface 5e is shorter than the distance between the lower end of the carry-in surface 5d and the lower end of the carry-out surface 5d. To do.

  The configuration of the holding and moving means 53 will be described. As shown in FIG. 2, the holding and moving means 53 is stretched over a pair of pulleys 531, one of which is arranged near the carry-in surface 5 d and the other is arranged near the carry-out surface 5 e, and the outer periphery of the pair of pulleys 531. And an annular belt 532 that moves as the pulley 531 rotates by a driving means (not shown).

  A plurality of plates 533 are erected substantially vertically on the entire outer peripheral surface of the annular belt 532 at a predetermined interval. Each plate 533 has an elastically deformable claw piece 534 that extends toward the adjacent plate 533.

  The operation of the holding and moving means 53 will be described. The holding and moving means 53 operates intermittently at a predetermined timing each time the paper P2 is carried to the carry-in position. When the paper P2 moves on the carry-in surface 5d, the lower end portion P2L of the paper P2 is inserted one by one into the recess 535 between the plates 533, and the paper P2 comes into contact with the annular belt 532.

  As described above, the carry-in position is a position below the storage unit 5 where the carried-in paper P2 can move on the carry-in surface 5d. In this embodiment, the lower end P2L of the paper P2 is inserted into the recess 535, This is the position where the paper P <b> 2 contacts the annular belt 532.

  In the vicinity of the carry-in surface 5d, the plate 533 on the upstream side of the movement faces the circumferential direction of the pulley 531, and the plate 533 on the downstream side of the movement faces substantially perpendicular to the annular belt 532, so the size of the recess 535 is larger than the thickness of the paper P2. The lower end portion P2L of the paper P2 can be inserted into the concave portion 535 between the plates 533.

  After the paper P2 is carried in, driving means (not shown) intermittently rotates the pulley 531 at a predetermined timing, whereby the plate 533 on the moving upstream side where the paper P2 is inserted into the recess 535 near the carry-in surface 5d. Also, it moves toward the carry-out surface 5e so as to be substantially perpendicular to the annular belt 532. Accordingly, the size of the concave portion 535 is reduced, and the claw piece 534 on the moving downstream side comes into contact with the lower end portion P2L and is elastically deformed, whereby the lower end portion P2L is moved to the plate 533 on the moving upstream side and the claw piece 534 on the moving downstream side. And is held by.

  The pulley 531 is further intermittently rotated to sequentially hold the lower end portion P2L of the loaded paper P2, and the lower end portion P2L is sequentially moved from the carry-in surface 5d to the carry-out surface 5e with the lower end portion P2L having a predetermined gap therebetween. Let When the moving downstream plate 533 moves to the vicinity of the carry-out surface 5e, the moving downstream plate 533 faces the circumferential direction of the pulley 531, the size of the concave portion 535 increases again, and the lower end portion P2L of the paper P2 is held. It is released sequentially. The printed surface of the paper P2 is dried by the moving time of the paper P2 from the carry-in surface 5d to the carry-out surface 5e, which is the intermittent operation.

  The position changing unit 54 determines the position of the upper end P2T of the sheet P2 that has been moved onto the carry-out surface 5e by the holding and moving unit 53 based on the size information SI acquired by the information acquiring unit 12 and transmitted from a control unit (not shown). Even when the paper sizes are different, the vertical position of the holding and moving means 53 is changed so that the predetermined height position is obtained.

  The configuration of the position changing unit 54 will be described. The position changing unit 54 is stretched over a driving roller 541 driven by a driving unit (not shown), a driven roller 542 disposed at a predetermined interval in the vertical direction with respect to the driving roller 541, and the driving roller 541 and the driven roller 542. An annular belt 543 and a moving element 544 fixed to the annular belt 543 and connected to the holding and moving means 53 by a fixture (not shown).

  The operation of the position changing unit 54 will be described. FIG. 4 shows a configuration diagram of the storage unit 5 in which the position of the holding and moving unit 53 is changed in the vertical position by the position changing unit 54. Based on the size information SI from the information acquisition unit 12, the position changing unit 54 ensures that the upper end P2T of the paper P2 moved onto the carry-out surface 5e by the holding and moving unit 53 is at a predetermined position on the carry-out surface 5e. By previously driving the drive roller 541 and moving the moving element 544 in the direction of arrow A in the figure, the vertical position of the holding and moving means 53 is adjusted as shown in FIG. Here, the vertical movement amount of the holding and moving means 53 is determined in correspondence with the movement amount of the upper end P2T on the carry-out surface 5e in the carry-out direction.

  FIG. 5 is a configuration diagram of the peeling means 55. The peeling unit 55 peels off the upper end portion P2U of the paper P2 carried to the carry-in position from the carry-in surface 5d, and restricts the upper end portion P2U from returning to the carry-in surface 5d again.

  The configuration of the peeling unit 55 will be described. The peeling means 55 includes a drive shaft 551 disposed above the unloading surface 5e side of the reservoir 5, a cam 552 that is substantially semicircular and is fixed to the drive shaft 551 at the center of the semicircle, and a cam 552. A movable guide 553 that is rotatably connected to the cam 552 in the vicinity of the circumference thereof, and a first guide shaft 554 that is inserted into a slot 553a formed in the movable guide 553 and guides the trajectory of the movable guide 553. Yes. The first guide shaft 554 is connected to one rotation shaft of a pickup roller pair 61 of the refeed unit 6 described later.

  Further, the peeling means 55 is fixed to the rotary shaft 555 disposed on the carry-in surface 5d side of the reservoir 5, the peeling claw 556 fixedly supported on the rotary shaft 555, and a spring (not shown). , A lever 557 biased in the direction of arrow A in the figure, one of which is rotatably connected to the lever 557 and the other of which is in contact with the outer peripheral surface 552a of the cam 552, and a slot 558a formed in the link 558. And a second guide shaft 559 that guides the track of the link 558.

  The operation of the peeling means 55 will be described. The peeling means 55 rotates the drive shaft 551 in the direction of arrow B in the figure by the drive means (not shown) substantially simultaneously with the paper P2 being carried to the carry-in position. As the drive shaft 551 rotates, the cam 552 rotates, and the movable guide 553 rotatably connected to the cam 552 is guided and moved by the first guide shaft 554 inserted into the slot 553a.

  As the cam 552 rotates, the outer peripheral surface 552a of the cam 552 contacts the link 558, whereby the link 558 is guided to the second guide shaft 559 and moves in the direction of arrow C in the figure. As the link 558 moves, the lever 557 rotates around the rotation shaft 555 against the biasing direction. By the rotation of the rotation shaft 555, the peeling claw 556 rotates around the rotation shaft 555 in the direction of arrow D in the figure. That is, the peeling means 55 operates the movable guide 553 and the peeling claw 556 in synchronization with the rotation of the drive shaft 551.

  A series of operations of the peeling means 55 will be described with reference to FIGS. 6A to 6D.

  As shown in FIG. 6A, the peeling means 55 is retracted from the carry-in surface 5d so that the peel claw 556 is substantially parallel to the carry-in surface 5d, and the movable guide 553 overlaps the upper end portions P2U on the carry-out surface 5e. In a state where the upper end portion P2U of the stacked paper P2 is held, it waits for the paper P2 to be carried to the carry-in position. The sheet P2 on the carry-out surface 5e is carried out at the timing when the peeling means 55 is on standby and the second plate cylinder 71 of the second printing unit 7 is at a predetermined position. That is, the standby movable guide 553 guides the conveyance of the paper P2 to the pickup roller pair 61.

  The peeling means 55 rotates the drive shaft 551 in the direction of arrow A in the figure by the drive means (not shown) substantially simultaneously with the paper P2 being carried to the carry-in position. Due to the rotation of the drive shaft 551, the movable guide 553 starts to move in a substantially unloading direction indicated by an arrow B in the figure.

  As shown in FIG. 6B, the rotation of the drive shaft 551 in the direction of arrow A in the drawing causes the outer peripheral surface 552a of the cam 552 to contact the link 558 and the peeling claw 556 rotates in the direction of arrow B in the drawing via the lever 557. Projecting on the carry-in surface 5d. When the peeling claw 556 protrudes on the carry-in surface 5d, the upper end portion P2U of the paper P2 is peeled from the carry-in surface 5d.

  As shown in FIG. 6C, when the drive shaft 551 further rotates, the peeling claw 556 further protrudes on the carry-in surface 5d, and the movable guide 553 moves in the substantially carry-out direction and then moves upward and in the carry-in direction. Further, when the equal circular portion of the outer peripheral surface 552a abuts on the lever 557, the separation claw 556 protruding on the carry-in surface 5d is stopped in a protruding state.

  After the movable guide 553 has moved in the substantially unloading direction, the movable guide 553 is moved upward in the vicinity of the loading surface 5d and in the substantially loading direction, so that the movable guide 553 is peeled off by the peeling claw 556 and moved downward. Is entered between the carry-in surface 5d and the upper end P2U of the paper P2. This restricts the upper end portion P2U of the paper P2 from returning again to the carry-in surface 5d due to the thickness of the paper P2, curling due to curling, and the airflow in the storage unit 5. By restricting the upper end portion P2U of the paper P2 from returning to the carry-in surface 5d again, the collision between the next paper P2 to be carried in and the upper end portion P2U of the paper P2 returning to the carry-out surface 5e can be avoided.

  As shown in FIG. 6D, when the drive shaft 551 further rotates, the outer peripheral surface 552a of the cam 552 is separated from the link 558, and the link 558 biased by a spring (not shown) returns to the original position in the direction of arrow A in the figure. Accordingly, the peeling claw 556 starts moving again toward the loading surface 5d side in the direction of arrow B in the drawing, and the movable guide 553 moved upward to the vicinity of the loading surface 5d is indicated by the arrow C in the drawing. It moves downward on the unloading surface 5e side shown. At this time, the movable guide 553 forcibly moves the upper end portion P2U of the paper P2 toward the carry-out surface 5e.

  Here, as described above, when the sheet P2 tries to return to the carry-in surface 5d again due to the thickness of the sheet P2, curling, or the airflow in the storage unit 5, the peeling unit 55 is configured to remove the sheet P2. The upper end P2U may be pressed and moved. However, when the paper P2 does not return to the carry-in surface 5d and moves to the carry-in surface 5d by its own weight, there is no need to press the paper P2. Any sheet that moves while restricting the return of the sheet P2 to the carry-in surface 5d may be used.

  As shown in FIG. 6A again, the peeling means 55 is retracted from the carry-in surface 5d so that the peeling claw 556 is substantially flat with respect to the carry-in surface 5d, and the movable guide 553 overlaps the upper end portions P2U on the carry-out surface 5e. Thus, the upper end portion P2U of the stacked paper P2 is held. The peeling means 55 has a specific operation cycle of about 0.6 seconds, of which about 0.5 seconds is in a standby state, and performs a series of operations in the remaining about 0.1 seconds.

  As described above, the movement changing unit 54 adjusts the upper end P2T of the paper P2 on the carry-out surface 5d so as to be at a predetermined height position even when the paper sizes are different. Here, in the present embodiment, as described above, the distance between the upper end of the carry-in surface 5d and the upper end of the carry-out surface 5e is shorter than the distance between the lower end of the carry-in surface 5d and the lower end of the carry-out surface 5d. In order to arrange the support plate 5a and the cover plate 5c, when the upper end P2T on the carry-out surface 5e is adjusted to a predetermined height position, the upper end P2T on the carry-in surface 5e is not necessarily the same as the carry-in surface 5d. It is not the predetermined height position above.

  However, as explained in the above series of operations, the peeling means 55 enters the movable guide 553 between the upper end portion P2U peeled off by the peeling claw 556 and the carry-in surface 5d, so that the upper end portion P2U again enters the carry-in surface 5d. Since the return is restricted, the position of the upper end P2T on the carry-in surface 5d may be adjusted so that the movable guide 553 enters between the peeled upper end part P2U and the carry-in surface 5d, and the paper size is reduced. Therefore, in order to make control common, stricter accuracy than the position of the upper end P2T on the carry-out surface 5e is not required.

  That is, the position changing means 54 changes the height position in the vertical direction so that the upper end P2T on the carry-out surface 5e becomes a predetermined height position regardless of the paper size, so that the upper end P2T on the carry-in surface 5d is changed. The position is almost the same height regardless of the paper size, and the control at the time of carry-in can be made common regardless of the paper size.

  The second transporting unit 56 carries out the paper P2 on the carry-out surface 5e from the storage unit 5 to the re-feeding unit 6.

  The second transporting unit 56 is different from the first transporting unit 51 in that the housing 561 is fixed to the support plate 5a and the sheet P2 does not need to be forcibly separated from the carry-out surface 5e. However, other configurations are substantially the same as those of the first transport unit 51, and detailed description thereof is omitted.

  The second conveying means 56 moves the paper P2 on the carry-out surface 5e on the carry-out surface 5e at the timing when a second plate cylinder 71 of the second printing unit 7 described later is at a predetermined position, and carries it out from the storage unit 5. . The operation of carrying out the paper P2 is substantially the same as that of the first transport unit 51, and the detailed description thereof is omitted.

  A description will be given with reference to FIG. 1 again. The refeed unit 6 refeeds the stored paper P2 to the second printing unit 7.

  The configuration of the refeed unit 6 will be described. The refeed unit 6 includes a pickup roller pair 61 that picks up the paper P2 carried out from the storage unit 5, and a timing roller pair 62 that feeds the picked up paper P2 to the second printing unit 7 at a predetermined timing. .

  The operation of the refeed unit 6 will be described. The pickup roller pair 61 sequentially picks up the paper P2 carried out from the second conveying means 56, and the timing roller pair 62 sends the picked up paper P2 to the second printing unit 7 at a predetermined timing.

  The second printing unit 7 prints on the other surface of the stored paper P2. The configuration and operation of the second printing unit 7 are the same as those of the first printing unit 3, and detailed description thereof is omitted.

  The paper discharge unit 8 discharges the paper P3 on which the other side is printed.

  The configuration of the paper discharge unit 8 will be described. The paper discharge unit 8 includes a paper discharge conveyance unit 81 that conveys the paper P3 printed on the other side by the second printing unit 7, and a paper discharge table 82 that is provided on the side of the apparatus main body 11 and stacks the paper P3. Consists of The paper discharge conveying means 81 includes a driving roller 81a, a driven roller 81b, a conveying belt 81c, and a suction fan 81d.

  The operation of the paper discharge unit 8 will be described. When the paper P3 printed on the other side by the second printing unit 7 is supplied onto the transport belt 81c, the paper discharge unit 8 sucks and transports the paper P3 by the suction fan 81d and stacks it on the paper discharge table 82.

  The overall operation of the duplex printing apparatus 1 will be described. The paper feeding unit 2 feeds the unprinted paper P1 to the first printing unit 3, and the first printing unit 3 prints on one side of the paper P1. The reversing unit 4 inverts the paper P2 and conveys it to the storage unit 5 so that one side of the printed paper P2 faces downward.

  In the storage unit 5, the first transport unit 51 sucks and transports the sheet P <b> 2 to the carry-in position with one side of the sheet P <b> 2 facing down. At this time, the curl imparting means 52 imparts a curl that is curved with the printed one side inward to the paper P2.

  The lower end portion P2L of the paper P2 carried into the carry-in position is held by the holding and moving means 53 and held and moved toward the carry-out surface 5e, and the upper end portion P2U of the paper P2 is peeled off from the carry-in surface 5d by the peeling means 55. In addition, it is restricted so as not to return to the carry-in surface 5d again.

  The holding and moving unit 53 changes the position based on the sheet size information SI from the information acquiring unit 12 so that the height position of the sheet P2 on the carry-out surface 5e is a predetermined height position regardless of the sheet size. The means 54 adjusts the position of the holding and moving means 53 in the height direction.

  The second transport means 56 carries out the paper P2 on the carry-out surface 5e from the storage unit 5 to the refeed unit 6, and the refeed unit 6 refeeds the paper P2 to the second printing unit 7 at a predetermined timing. To do. The second printing unit 7 prints on the other side of the paper P2, and the paper discharge unit 8 discharges the paper P3 on which the other side is printed. Specifically, the duplex printing apparatus 1 can print one side and the other side of the paper P1 in a cycle of about 100 sheets per minute.

  In this embodiment, the double-sided printing apparatus 1 has been described as a double-sided stencil printing apparatus. However, the present invention is not particularly limited to this, and an inkjet printer or the like that can print on one side and the other side of the unprinted paper P1. It does not matter.

  As described above, according to the double-sided printing apparatus 1 according to the embodiment of the present invention, the position changing unit 54 determines the position of the upper end P2T of the paper P2 on the carry-out surface 5e in advance based on the size information SI. In order to change the vertical position of the holding and moving means 53 so as to be the height position, the distance between the upper end P2T of the paper P2 moved onto the carry-out surface 5e by the holding and moving means 53 and the second printing unit 7 is It is constant regardless of the paper size, and the control at the time of carrying out the paper P2 can be made common.

  Further, according to the double-sided printing device 1, even when the peeling unit 55 peels off the upper end portion P2U of the paper P2 from the carry-in surface 5d and restricts the upper end portion P2U from returning to the carry-in surface 5d again. By changing the vertical position of the holding and moving means 53 so that the upper end P2T of the paper P2 on the carry-out surface 5d becomes a predetermined height position, the position of the upper end P2 on the carry-in surface 5d is also substantially the same. The height can be set, and the control at the time of carrying in the paper P2 can be made common regardless of the paper size.

P1, P2 paper SI size information P2L lower end P2U upper end 1 double-sided printing device 3 first printing unit 5 storage unit 5d carry-in surface 5e carry-out surface 7 second printing unit 12 information acquisition unit 53 holding and moving unit 54 position changing unit 55 peeling means

Claims (2)

A first printing unit that prints on one side of the paper, a storage unit that receives the paper on which the one side is printed, stores the loaded paper, and prints on the other side of the paper that has been carried out of the storage unit A double-sided printing apparatus comprising a printing unit,
An information acquisition means for acquiring size information of the paper;
The reservoir is
The lower end portions of the sheets sequentially loaded into the loading position in the storage unit are sequentially held, and the respective sheets holding the lower end portions are sequentially discharged in the storage unit with their lower ends spaced apart from each other by a predetermined gap. Holding and moving means for moving toward the
And a position changing means for changing the vertical position of the holding and moving means so that the upper end position of the sheet at the carry-out position becomes a predetermined height position based on the size information. Double-sided printing device. The reservoir is
A carry-in surface on which the paper carried into the carry-in position moves;
2. A peeling means for separating an upper end portion of the paper carried into the carry-in position from the carry-in surface and restricting the upper end portion from returning to the carry-in surface again. 2. The double-sided printing apparatus described in 1.

Images