JP2008302556A - Stencil process printing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stencil process printing device capable of performing a successful printing process by inhibiting the generation of a paper riding-up jam. <P>SOLUTION: This stencil process printing device 1 comprises a plate cylinder 9, a pressing means 10 which presses paper P to the plate cylinder 9 and an air blower means 38 which blows air to release the paper P pressed to the plate cylinder 9 by the pressing means 10, from the outer peripheral surface of the plate cylinder 9. In addition, a guide member 31 is provided which can prevent the air blown out by the air blower means 38 from flowing out to the outside of a pressure contacting part between the plate cylinder 9 and the pressing means 10. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

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

  Conventionally, digital thermal stencil printing is known as a simple printing method. This is because a thermal head having a plurality of fine heating elements is brought into contact with a master obtained by bonding a thermoplastic resin film and a porous support, and the master is placed on a platen roller or the like while energizing the heating elements in a pulsed manner. After the perforated image based on the image information is hot-melt perforated and engraved on the thermoplastic resin film of the master by conveying with a conveying means, this perforated master is wound around a porous cylindrical plate cylinder and pressed. By pressing the paper against the outer peripheral surface of the plate cylinder by means, the ink oozed from the opening portion of the plate cylinder and the perforation portion of the master is transferred to the paper, and a printed image is obtained on the paper.

  As a stencil printing apparatus for performing this stencil printing, a device provided with a peeling means for peeling printed paper pressed against the outer peripheral surface of the plate cylinder by a pressing means is generally known. This peeling means usually has a claw shape having a sharp tip inserted between the outer surface of the plate cylinder and the paper, and the peeling position where the tip is close to the outer surface of the plate cylinder and the outer surface of the plate cylinder It is configured to be swingable so as to selectively occupy a retreat position that avoids interference with a clamper or the like provided on the outer peripheral surface of the plate cylinder further apart. Also, since it is difficult to completely peel off the paper with only the claw-like peeling means, there is also known an apparatus provided with a blowing means for blowing air toward the paper peeling position.

  However, even in an apparatus provided with a peeling means and a blowing means, if a large solid image exists near the leading edge where the paper is peeled off, the adhesive force of the ink is strong and the plate cylinder outer peripheral surface and the paper There is a problem in that the paper is not completely peeled off, and a paper roll-up jam occurs in which the paper is wound up on the outer peripheral surface of the plate cylinder. In order to solve this problem, for example, “Patent Document 1” discloses a technique in which an air blowing unit is provided in a blowing unit in order to perform an optimum blowing according to various printing conditions.

JP 2000-301818 A

  However, in the technique disclosed in “Patent Document 1”, the wind blown from the blowing means escapes into the space inside the apparatus, and the separation efficiency by wind force may decrease. This is particularly significant when the margin at the leading edge of the paper is small. In such a case, the paper is in close contact with the plate cylinder and the paper rolls up frequently.

  SUMMARY OF THE INVENTION It is an object of the present invention to provide a stencil printing apparatus that solves the above-described problems and can perform good printing by preventing the occurrence of paper roll-up jamming.

  According to the first aspect of the present invention, the plate cylinder, the pressing unit that presses the sheet against the plate cylinder, and the air blown to peel the sheet pressed against the plate cylinder by the pressing unit from the outer peripheral surface of the plate cylinder. A stencil printing apparatus having a blowing unit includes a guide member for preventing the wind sent from the blowing unit from flowing out of a pressure contact portion between the plate cylinder and the pressing unit.

  According to a second aspect of the present invention, in the stencil printing apparatus according to the first aspect, the guide member is configured integrally with the air blowing means.

  According to a third aspect of the present invention, in the stencil printing apparatus according to the second aspect, at least two of the blowing means and the guide member are further provided.

  According to a fourth aspect of the present invention, in the stencil printing apparatus according to the third aspect, the image identification means for identifying the pixel density in the original image, and the blowing of each of the blowing means according to the identified pixel density are controlled. And a control means.

  According to a fifth aspect of the present invention, the plate cylinder, a pressing unit that presses the sheet against the plate cylinder, and air is blown to peel the sheet pressed against the plate cylinder by the pressing unit from the outer peripheral surface of the plate cylinder. In the stencil printing apparatus having a blowing means, the stencil printing machine has a pair of guide members for preventing the wind sent from the blowing means from flowing out of the pressure contact portion between the plate cylinder and the pressing means, and each of the guides The members are characterized in that the distance between them can be adjusted.

  According to a sixth aspect of the present invention, in the stencil printing apparatus according to the fifth aspect of the present invention, the distance between the guide members can be automatically adjusted according to the width of the paper to be used.

  According to the present invention, when the paper that has been pressed onto the outer peripheral surface of the plate cylinder by the pressing unit and the image is transferred is peeled off from the outer peripheral surface of the plate cylinder by the blowing unit, the wind discharged from the blowing unit by the guide member is Escape to the space inside the device is prevented, and the wind blown from the air blowing means will act efficiently on the separation position between the plate cylinder and the paper, preventing the occurrence of paper roll-up jam and good printing. It can be carried out.

  FIG. 1 shows a stencil printing apparatus that employs a 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 and a press roller 10 as pressing means.
The plate cylinder 9 is rotatably supported by a support shaft 11 that also serves as an ink supply pipe. The plate cylinder 9 is rotatably driven by a plate cylinder driving means (not shown) and is detachable from the apparatus main body 8. An ink supply means 14 having an ink roller 12, a doctor roller 13, etc. is disposed inside the plate cylinder 9, and a clamper 15 that holds the tip of the master is attached to the outer peripheral surface of the plate cylinder 9 so as to be freely opened and closed. It has been. On the outer peripheral surface of the plate cylinder 9, an opening having a large number of perforations for allowing the ink supplied from the ink supply means 14 to bleed out is provided.

  Below the plate cylinder 9, there is disposed a press roller 10 in which both ends of the support shaft are rotatably supported by a pair of arm members 16. In the press roller 10, each arm member 16 is oscillated by an oscillating means (not shown), so that a predetermined pressure contact force is applied to the separation position separated from the outer peripheral surface of the plate cylinder 9 and the outer peripheral surface of the plate cylinder 9 shown in FIG. It selectively occupies the press-contact position to press-contact with.

A plate making unit 3 is disposed in the upper right part of the apparatus main body 8. The plate making unit 3 includes a master holding member 17, a platen roller 18, a thermal head 19, a master cutting means 20, master transport roller pairs 21 and 22, and the like.
The master holding member 17 is attached to a side plate (not shown) of the apparatus main body 8, and has a core portion of a master roll 23a obtained by winding a master 23 formed by laminating a thermoplastic resin film and a porous support in a roll shape. Supports rotation and detachment.

  A platen roller 18 disposed on the left side of the master holding member 17 is rotatably supported on a side plate (not shown) of the apparatus body 8 and is driven to rotate by a stepping motor 24. A thermal head 19 positioned below the platen roller 18 and having a large number of heat generating elements is attached to a side plate (not shown) of the apparatus main body 8, and the surface of the heat generating elements is arranged around the platen roller 18 by a biasing force of a biasing means (not shown). It is pressed against the surface. The thermal head 19 selectively heats each heating element while contacting the surface of the thermoplastic resin film of the master 23, and performs hot melt perforation plate-making on the master 23.

  Master cutting means 20 is disposed on the left side of the platen roller 18 and the thermal head 19. The master cutting means 20 having a fixed blade fixed to a frame (not shown) of the apparatus main body 8 and a movable blade supported so as to be movable with respect to the fixed blade has the movable blade rotated or moved with respect to the fixed blade. The master 23 is cut by moving up and down.

  On the left side of the master cutting unit 20, a pair of master transport rollers 21 and 22 is disposed. Each of the master conveying roller pairs 21 and 22 has a driving roller and a driven roller that are rotatably supported by a side plate (not shown) of the apparatus main body 8, and each driving roller is a platen roller 18 by a driving means (not shown). The driven rollers are rotationally driven in the same direction in synchronism with each other, and the driven rollers are pressed against the corresponding driving rollers by urging means (not shown).

  A sheet feeding unit 4 is disposed below the plate making unit 3. The paper feed unit 4 includes a paper feed tray 25, a paper feed roller 26, a separation roller pair 27, a registration roller pair 28 as a feeding unit, and the like. A sheet feeding tray 25 on which a large number of sheets P can be stacked on the upper surface 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 25 having a housing shape has a plurality of sensors 29 for detecting the size of the stacked paper P, and the upper surface of the paper feed tray 25 is mutually oriented toward the paper width direction perpendicular to the paper transport direction. A pair of side fences 30 that can move in synchronism are provided.

  Above the left end of the paper feed tray 25, a paper feed roller 26 having a high friction resistance member on the surface is disposed. The paper feed roller 26 is rotatably supported by a bracket (not shown) that is swingably supported by the apparatus main body 8. When the paper feed tray 25 is raised by a lifting means (not shown), the paper feed roller 26 is supplied with a predetermined pressure. The uppermost sheet P on the paper tray 25 is pressed against. The paper feed roller 26 is rotationally driven by a paper feed motor 32 comprising a stepping motor.

  A separation roller pair 27 is disposed on the left side of the paper feed roller 26. The separation roller pair 27 has an upper roller and a lower roller each having a high friction resistance member on the surface, and the upper roller is rotated in the same direction in synchronism with the rotation of the paper feed roller 26 by the paper feed motor 32. Driven by rotation. The lower roller is pressed against the upper roller with a predetermined pressing force by a biasing force of a biasing means (not shown), and is configured to be rotatable only in the same direction as the upper roller.

  On the left side of the separation roller pair 27, a registration roller pair 28 having a driving roller 28a and a driven roller 28b is disposed. The drive roller 28a is rotatably supported between side plates (not shown) of the apparatus main body 8, and is driven to rotate in synchronization with the plate cylinder 9 by transmitting a rotational drive force from a plate cylinder drive means (not shown). The driven roller 28b is rotatably supported between side plates (not shown) of the apparatus body 8, and is pressed against the drive roller 28a with a predetermined pressing force by a biasing force of a biasing means (not shown).

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 33, a lower plate removal member 34, a plate removal box 35, a compression plate 36, and the like.
Both the upper plate removal member 33 and the lower plate removal member 34 have a drive roller, a driven roller, an endless belt, and the like, and the endless belt moves when the drive roller is rotationally driven by a plate drive unit (not shown). Further, the lower plate discharge member 34 is configured to be movable by a moving means (not shown), and selectively occupies an initial position shown in the drawing and a peeling position where the endless belt contacts the outer peripheral surface of the plate cylinder 9.

  The plate removal box 35 for storing the used master therein is configured to be detachable from the apparatus main body 8. A compression plate 36 for pushing the used master carried by the upper plate removal member 33 and the lower plate removal member 34 into the plate release box 35 is supported by the apparatus main body 8 so as to be movable up and down, and is moved up and down by a lifting means (not shown). The

A paper discharge unit 6 is disposed below the plate discharge unit 5. The paper discharge unit 6 includes a guide member 31 that is a characteristic part of the present invention, in addition to known configurations such as a peeling claw 37, a blower 38, a paper transport unit 39, and a paper discharge tray 40.
2, the base end of the peeling claw 37 is rotatably attached to a support shaft 49 supported by the apparatus main body 8, and is rotated by a predetermined angle by a claw swinging means (not shown). The free end formed in an acute angle shape is configured to be close to and away from the outer peripheral surface of the plate cylinder 9.

  One blowing means 38 is disposed above the peeling claw 37 (not shown in FIG. 2). By blowing air toward the free end of the peeling claw 37, the paper P is peeled from the plate cylinder 9. Prompt. As shown in FIG. 3, the air blowing means 38 has a pump 61 having a cylinder and a piston, a reserve tank 62 that stores air discharged from the pump 61, and a valve of the reserve tank 62 that opens and closes the air in the reserve tank 62. A solenoid 63 for discharging, a hose 64 for sending out discharged air, and the like are included. The valve state of the reserve tank 62 is detected by a solenoid sensor 65 (see FIG. 5), and the operation of the solenoid 63 is controlled by the control means 50 described later. In this example, the pump 61 and the reserve tank 62 are directly connected, but a regulator may be interposed between them in order to maintain a constant air pressure.

  Two plate-like guide members 31 are arranged corresponding to both side edge portions of the plate cylinder 9, and each guide member 31 has a base end fixed to a support shaft 49. Each guide member 31 has an arc shape along the outer peripheral surface of the plate cylinder 9 at its free end, and is at a position where it does not interfere with the clamper 15 that moves as the plate cylinder 9 rotates. 9 is arranged in a manner closest to the outer peripheral surface.

  The sheet conveying means 39 disposed on the lower left side of the peeling claw 37 includes a driving roller, a driven roller, an endless belt, a suction fan, and the like. The driving roller is driven to rotate by a paper discharge driving means (not shown). By operating the suction fan, the sheet P is conveyed to the left while being sucked onto the endless belt.

  A paper discharge tray 40 is disposed on the left side of the paper transport means 39. A paper discharge tray 40 on which a large number of printed paper P conveyed by the paper discharge conveying means 39 is stacked has one end fence 41 and a pair of side fences 42 for aligning the paper P on its upper surface. is doing. The end fence 41 is movable in the same direction as the paper conveyance direction, and each side fence 42 is configured to be able to contact and separate from each other in the same direction as the paper width direction.

  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 43 on which a document is placed, a pressure plate 44 that can be moved toward and away from the contact glass 43, a scanning unit 45 that scans and reads a document image, a lens 46 that focuses the scanned image, and a focus. An image sensor 47 such as a CCD for processing the obtained image is provided. An ADF unit 48 used for automatically reading a plurality of documents is disposed on the pressure plate 44.

  FIG. 4 shows an operation panel of the stencil printing apparatus 1. In the figure, an operation panel 51 has a known configuration such as a plate making start key 52, a printing start key 53, a stop key 54, a numeric keypad 55, a display device 56 comprising a 7-segment LED, a display device 57 comprising an LCD, and the like. .

  FIG. 5 is a block diagram of control means used in the stencil printing apparatus 1. In the figure, a control means 50 composed of a well-known microcomputer having a CPU 58, a ROM 59, a RAM 60 and the like is provided inside the apparatus main body 8. An operation signal from the operation panel 51 and detection signals from various sensors including the solenoid sensor 65 are input to the control means 50, and the control means 50 receives the printing unit 2, the plate making unit 3, the paper feeding unit based on the signals. 4. Controls the operations of the plate discharge unit 5, the paper discharge unit 6, the image reading unit 7, the solenoid 63, and the like.

Based on the above configuration, the operation of the stencil printing apparatus 1 will be described below.
After the manuscript is placed on the contact glass 43 by the operator, when the plate making start key 52 on the operation panel 51 is pressed in a state where the pressure plate 44 is closed, the image reading unit 7 performs a manuscript image reading operation. Is called. The image is read by scanning the original image with the scanning unit 45, and the read image is focused by the lens 46 and then sent to the image sensor 47.

  In parallel with the image reading operation, the plate discharging unit 5 performs a plate discharging operation for peeling the used master from the outer peripheral surface of the plate cylinder 9. When the plate making start key 52 is pressed, the plate cylinder 9 starts to rotate, and when reaching a predetermined plate discharging position, the rotation is stopped. Then, the lower plate removal member 34 is actuated and moved to the peeling position, and the used master on the plate cylinder 9 is scooped up by the lower plate removal member 34. Thereafter, the plate cylinder 9 rotates and the upper plate discharge member 33 is operated, and the used master on the plate cylinder 9 is conveyed by the plate discharge members 33 and 34 and stored in the plate discharge box 35. Thereafter, the compression plate 36 is operated to compress the used master in the discharge plate box 35 and the plate cylinder 9 is rotated to a predetermined plate feeding position and stopped. The clamper 15 is opened and the stencil printing apparatus 1 is fed. It becomes a plate standby state.

  When the stencil printing apparatus 1 enters a stencil supply standby state, the platen roller 18 and each of the master transport roller pairs 21 and 22 are rotationally driven, and the master 23 is pulled out from the master roll 23a. The drawn master is punched when passing through the thermal head 19, and a plate-making image is formed on the surface of the thermoplastic resin film. The master 23 is sent to the clamper 15 while making a plate, and when the control means 60 determines that the tip of the master 23 has been conveyed to a position that can be held by the clamper 15 based on the number of steps of the stepping motor 24, the clamper 15 is closed and the plate is made. The master 23 is held on the outer peripheral surface of the plate cylinder 9 at the tip.

  Thereafter, the plate cylinder 9 is rotationally driven at the same peripheral speed as the conveying speed of the master 23, and the winding operation of the master 23 around the plate cylinder 9 is performed. When the master 23 for one plate is made, the operations of the platen roller 18 and each of the master conveying rollers 21 and 22 are stopped and the master cutting means 20 is operated to cut the master 23. The cut master 23 is pulled out from the plate making section 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 is stopped at the home position, the paper feed unit 4 is operated to pull out the uppermost sheet P from the paper feed tray 25, and the leading end is sandwiched between the registration roller pair 28, and the plate The cylinder driving means 49 is actuated to rotate the plate cylinder 9 at a low speed in the clockwise direction in FIG. Then, the driving roller 28a is driven to rotate at a predetermined timing when the leading end of the image area of the master 23 wound around the plate cylinder 9 reaches the contact portion with the press roller 10 in the direction of rotation of the plate cylinder, and the sheet P is transferred to the plate cylinder. 9 is fed toward the contact portion between the press roller 10 and the press roller 10. Almost simultaneously with the rotation of the drive roller 28a, the press roller 10 presses the peripheral surface thereof against the outer peripheral surface of the plate cylinder 9 by the operation of a swinging means (not shown), and the fed paper P presses against the master 23 on the plate cylinder 9. Is done. By this pressing operation, the press roller 10, the paper P, the master 23, and the plate cylinder 9 are pressed against each other, and the ink supplied to the inner peripheral surface of the plate cylinder 9 by the ink roller 12 oozes out from the opening portion of the plate cylinder 9, After being filled in the porous support of the master 23, it is transferred to the paper P through the perforated part of the master 23, and so-called printing is performed.

  The sheet P to which the image has been transferred by printing is peeled off from the outer peripheral surface of the plate cylinder 9 by the peeling claw 37 and the air blowing means 38, dropped downward and sent to the sheet conveying means 39, and then the sheet conveying means. The sheet is sucked and conveyed by the sheet 39 and discharged onto the sheet 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 the print start key 53 is pressed after the number of prints is set by the ten key 55 on the operation panel 51, the paper P is continuously fed from the paper supply unit 4. The printing operation is performed in the same manner as in the printing operation. 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.

  During the printing operation and the printing operation described above, the sheet P on which the image is transferred by being pressed against the outer peripheral surface of the plate cylinder 9 by the press roller 10 is peeled off from the outer peripheral surface of the plate cylinder 9 by the peeling claw 37 and the blowing means 38. However, at this time, the air discharged from the air blowing means 38 by each guide member 31 is prevented from escaping into the space inside the apparatus, and the air discharged from the air blowing means 38 is efficiently transferred between the plate cylinder 9 and the paper P. Since this acts on the peeling position, it is possible to prevent the occurrence of paper roll-up jam and to perform good printing. In the above embodiment, only one blowing unit 38 is provided, but a plurality of blowing units 38 may be provided.

  FIG. 6 shows the air blowing means 66 used in the second embodiment of the present invention. The air blowing means 66 is different from the air blowing means 38 shown in the first embodiment only in that a guide member 67 is integrally provided at the tip of the hose 64, and other configurations are the same. is there. Two blower means 66 are arranged, and each guide member 67 is fixed at the same position as each guide member 31 shown in the first embodiment.

  With the above-described configuration, the stencil printing apparatus 1 can save space as compared with the first embodiment, and the air discharged from the blowing unit 66 acts on both ends of the paper P, so that the peelability is improved. Can be improved. In the second embodiment, a configuration in which a blower similar to the blower 38 is provided in addition to the two blowers 66 may be employed.

  FIG. 7 shows a block diagram of the control means 50 in the third embodiment of the present invention. The third embodiment is different from the second embodiment only in the operation control of each blowing unit 66 by the control unit 50, and the other configurations are the same. The control unit 50 controls the operation of the solenoid 63 of each blowing unit 66 based on the pixel density information from the image identification unit 68 and the printing speed information from the printing speed setting unit 69. The image identification unit 68 determines how the pixel density of the document image read by the image reading unit 7 is distributed on the document, and transmits the information to the control unit 50. The printing speed setting means 69 is provided on the operation panel 51 and is used when arbitrarily setting the printing speed.

  For example, in the case of a document having a large solid image on the guide member 67 side located on the front side of the apparatus, the control unit 50 is identified by the printing speed set by the printing speed setting unit 69 and the image identification unit 68. Based on the document image information, the valve opening time of each blowing means 66 is selected from parameters that set the relationship between the preset speed and solid image area and the valve opening time of the reserve tank 62, and is positioned on the front side of the apparatus. The operation of each blowing means 66 is controlled so that the blowing time of the blowing means 66 to be longer than the blowing time of the blowing means 66 located on the back side of the apparatus.

  With the above-described configuration, the operation of each blowing unit 66 can be controlled in accordance with the position of the solid image on the document image, and the air blown according to the size and position of the solid image that greatly affects the paper roll-up jam. By doing so, it is possible to effectively prevent the occurrence of paper roll-up jams and perform better printing.

  In the second and third embodiments, each guide member 67 is fixed to the apparatus main body 8, but each guide member 67 may be configured to be movable in the axial direction on the support shaft 49. With this configuration, each guide member 67 can be positioned at an appropriate position according to the width of the paper P to be used, and the paper P is peeled off from the plate cylinder 9 so that paper roll-up jam occurs. Can be effectively prevented.

  Further, each guide member 67 may be automatically moved in the axial direction of the support shaft 49. Hereinafter, the fourth embodiment will be described. The fourth embodiment is different from the second and third embodiments described above only in that each guide member 67 can automatically move on the support shaft 49, and the other configurations are the same.

  In FIG. 8, each guide member 67 is attached to a support shaft 49 via a bracket 70 so as to be movable in the axial direction. A rack member 72 is attached to each bracket 70 via an attachment member 71. It is fixed. The rack portions of the rack members 72 face each other, and a pinion 73 is disposed at the center thereof so as to mesh with the rack portions. The pinion 73 is rotationally driven by a stepping motor 75 via an endless belt 74. Reference numeral 76 denotes a sensor for detecting the home position of each guide member 67.

  FIG. 9 shows a block diagram of the control means 50 in the fourth embodiment. The control means 50 acquires the size of the paper P to be used based on the signal output from the sensor 29, and operates the stepping motor 75 according to this size to position each guide member 67 to the size of the paper P. Move to. The operation of the stencil printing apparatus 1 in the fourth embodiment will be described below based on the flowchart shown in FIG.

  The control means 50 first checks whether or not a signal from the sensor 76 is sent, and recognizes that each guide plate 67 is located at the home position when the signal from the sensor 76 is sent. Next, a paper size signal is received from the sensor 29, and when the plate making start key 52 on the operation panel 51 is pressed, the stepping motor 75 is operated to move each guide plate 67 to a position corresponding to the size of the paper P. Let Next, the control unit 50 calls up the operation parameters of each blowing unit 66 based on information from the image identification unit 68 and the printing speed setting unit 69 and controls the operation of each blowing unit 66.

  According to the above-described configuration, the position of each guide plate 67 can be determined according to the size of the paper P, and the operation of the air blowing means 66 can be controlled according to the position of the solid image on the original image. It is possible to more effectively prevent the occurrence of the rising jam and to perform better printing.

  In each of the above-described embodiments, an example in which the press roller 10 is used as the pressing means has been described. However, instead of the press roller 10, an impression cylinder having the same diameter as the pressing cylinder 9 and being driven to rotate in synchronization with the printing cylinder 9 is used. It is good also as a structure using.

1 is a schematic front view of a stencil printing apparatus adopting a first embodiment of the present invention. FIG. 2 is a schematic perspective view of the vicinity of a plate cylinder used in the first embodiment of the present invention. It is the schematic of the ventilation means used for the 1st Embodiment of this invention. It is the schematic of the operation panel used for the 1st Embodiment of this invention. It is a block diagram of the control means used for the 1st Embodiment of this invention. It is the schematic of the ventilation means used for the 2nd Embodiment of this invention. It is a block diagram of the control means used for the 3rd Embodiment of this invention. It is the schematic which shows the moving mechanism of the guide member used for the 4th Embodiment of this invention. It is a block diagram of the control means used for the 4th Embodiment of this invention. It is a flowchart explaining the operation | movement of the 4th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Stencil printing apparatus 9 Plate cylinder 10 Pressing means (press roller)
31, 67 Guide member 38, 66 Blowing means 50 Control means 68 Image identification means P Paper

Claims (6)

A stencil printing apparatus comprising: a plate cylinder; a pressing unit that presses a sheet against the plate cylinder; and a blowing unit that blows air so that the sheet pressed against the plate cylinder by the pressing unit is separated from the outer peripheral surface of the plate cylinder. In
A stencil printing apparatus, comprising: a guide member that prevents the wind sent from the blowing means from flowing out of a pressure contact portion between the plate cylinder and the pressing means. In the stencil printing apparatus according to claim 1,
The stencil printing apparatus, wherein the guide member is formed integrally with the air blowing means. In the stencil printing apparatus according to claim 2,
A stencil printing apparatus, wherein at least two of the air blowing means and the guide member are provided. In the stencil printing apparatus according to claim 3,
An stencil printing apparatus, comprising: an image identification unit that identifies a pixel density in a document image; and a control unit that controls the blowing of each of the blowing units according to the identified pixel density. A stencil printing apparatus comprising: a plate cylinder; a pressing unit that presses a sheet against the plate cylinder; and a blowing unit that blows air so that the sheet pressed against the plate cylinder by the pressing unit is separated from the outer peripheral surface of the plate cylinder. In
It has a pair of guide members that prevent the wind sent from the blowing means from flowing out of the pressure contact portion between the plate cylinder and the pressing means, and the guide members are configured to be able to adjust the distance between them. A stencil printing apparatus characterized by being made. In the stencil printing apparatus according to claim 5,
The stencil printing apparatus, wherein each guide member is capable of automatically adjusting a distance between the guide members according to the width of the paper to be used.

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