JP2017030191A - Stencil printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stencil printer which can properly perform printing processing or plate-making processing even if a rotary transfer position of a printing plate cylinder deviates when the printer is not at the time of power-on or the time of return from the power-saving mode.SOLUTION: The stencil printer comprises: a malfunction detection unit 53 which detects malfunction related to at least one of a printing sheet and a stencil sheet N in the periphery of a printing plate cylinder 11; and a control unit 6 which controls a drive unit 9 so as to execute printing processing or plate-making processing after the printing plate cylinder 11 is rotated to a reference position if a reference position detection unit 80 detects that the printing plate cylinder 11 is not located at the reference position when starting the printing processing or plate-making processing after the malfunction detection unit 53 detects malfunction related to at least one of the printing sheet and the stencil sheet.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a stencil printing apparatus.

  In the stencil printing apparatus, regarding the technology for detecting the rotational phase angle of the printing plate cylinder and starting the printing after setting the rotational phase position to an appropriate rotational phase position, the following Patent Documents 1 and 2 include the following: It is described that an initialization process is performed in which the printing plate cylinder is moved to the initial position when returning.

JP 2014-108603 A Japanese Patent No. 4037192

  In the stencil printing apparatuses described in Patent Documents 1 and 2, the printing plate cylinder can be moved to the initial position when the power is turned on or when returning from the power saving mode. On the other hand, when some trouble such as a paper jam occurs during the printing process or when the printing plate cylinder is detached from the apparatus main body, the rotational transfer position of the printing plate cylinder may be displaced. In such a case, an appropriate printing process may be difficult.

  The present invention can properly perform printing processing or plate making processing even when the rotational transfer position of the printing plate cylinder is shifted when the power is not turned on or when returning from the power saving mode. An object of the present invention is to provide a stencil printing apparatus.

  In order to solve the above problems, the stencil printing apparatus of the present invention is a printing plate cylinder on which a stencil sheet is wound, a drive unit that rotationally drives the printing plate cylinder, and the printing plate cylinder in the rotation direction. A reference position detection unit that detects whether or not the printer is located at a predetermined reference position, a defect detection unit that detects a defect related to at least one of printing paper and stencil sheet around the printing plate cylinder, and the defect detection unit that performs printing When the reference position detection unit detects that the printing plate cylinder is not located at the reference position when starting the printing process or the plate making process after detecting a defect related to at least one of the paper and the stencil sheet Includes a control unit that controls the drive unit to execute a printing process or a plate-making process after the printing plate cylinder has been rotated to the reference position.

Further, in the above configuration, the defect detection unit includes at least printing paper conveyance failure, plate-making stencil sheet printing failure on the printing plate cylinder, and used stencil sheet discharge failure from the printing plate cylinder. Detect any defect.

The stencil printing apparatus of the invention includes a printing plate cylinder on which a stencil sheet is wound, a drive unit that rotationally drives the printing plate cylinder, and the printing plate cylinder positioned at a predetermined reference position in the rotation direction. A reference position detecting unit for detecting whether or not to perform, an opening / closing detecting unit for detecting an opening / closing operation of a discharging box for collecting used stencil paper, and printing after the opening / closing detecting unit detects an opening / closing operation of the discharging box When starting the processing or the plate making process, when the reference position detection unit detects that the printing plate cylinder is not located at the reference position, the printing plate cylinder is rotated to the reference position. And a control unit that controls the drive unit to execute a printing process or a plate making process later.

Further, the stencil printing apparatus of the present invention comprises a printing plate cylinder on which a stencil sheet is wound, a drive unit that rotationally drives the printing plate cylinder, and the printing plate cylinder at a predetermined reference position in the rotational direction. A reference position detecting unit for detecting whether or not the printing plate cylinder is attached, an attachment / detachment detecting unit for detecting an attachment / detachment operation of the printing plate cylinder to the apparatus main body, and after the attachment / detachment detection unit detects the attachment / detachment operation of the printing plate cylinder When starting the printing process or the plate making process, if the reference position detecting unit detects that the printing plate cylinder is not located at the reference position, the printing plate cylinder is rotated to the reference position. And a control unit that controls the drive unit to execute the printing process or the plate making process.

In each of the above configurations, the reference position detection unit includes an optical sensor and a light shielding member, and the sensor detects an edge of the light shielding member, thereby causing the reference position to be detected.

In each of the above configurations, the reference position is a position where rotation of the printing plate cylinder is started in order to execute a printing process, and a start position of a plate discharging process where the used stencil sheet is peeled off from the printing plate cylinder. is there.

According to the present invention, a defect detection unit that detects a defect related to at least one of printing paper and stencil paper around the printing plate cylinder, and after the defect detection unit detects a problem related to at least one of printing paper and stencil paper When starting the printing process or the plate making process, if the reference position detecting unit detects that the printing plate cylinder is not located at the reference position, the printing plate cylinder is rotated to the reference position. And a control unit that controls the drive unit so as to execute the printing process or the plate making process after that, in order to solve the problem of at least one of the printing paper and the stencil sheet around the printing plate cylinder Even if the printing plate cylinder is manually rotated to a position different from the reference position, the control unit detects the value detected by the defect detection unit. The driving unit is driven based on, it is possible to perform the printing process or stencil making process for printing plate cylinder after rotated to the reference position.

In addition, the defect detection unit has at least one of the following problems: improper printing paper conveyance, defective plate-making stencil sheet to the printing plate cylinder, and defective stencil printing of the used stencil sheet from the printing plate cylinder In the case of detecting the error, it is possible to appropriately deal with a frequently occurring defect around the printing plate cylinder.

An open / close detection unit that detects an open / close operation of a discharge box for collecting used stencil paper, and the reference when the open / close detection unit starts the printing process or the plate making process after detecting the open / close operation of the discharge box When the position detecting unit detects that the printing plate cylinder is not located at the reference position, the printing plate cylinder is driven to execute the printing process or the plate making process after rotating the printing plate cylinder to the reference position. A control unit that controls the printing section, so that when the plate opening / closing operation is performed, even if the printing plate cylinder rotates and is at a position different from the reference position, the printing process or The plate making process can be executed.

Further, an attachment / detachment detection unit that detects an attachment / detachment operation of the printing plate cylinder to the apparatus main body, and the reference when the attachment / detachment detection unit starts the printing process or the plate making process after detecting the attachment / detachment operation of the printing plate cylinder. When the position detecting unit detects that the printing plate cylinder is not located at the reference position, the printing plate cylinder is driven to execute the printing process or the plate making process after rotating the printing plate cylinder to the reference position. And a control unit for controlling the printing unit, so that when the printing plate cylinder is attached to and detached from the apparatus main body, the printing plate cylinder is rotated to a position different from the reference position. In addition, the printing process or the plate making process can be appropriately executed.

Further, the reference position detection unit includes an optical sensor and a light shielding member. When the reference position is detected by the sensor detecting the edge of the light shielding member, the reference position can be easily detected. is there.

Further, the reference position is a position where rotation of the printing plate cylinder is started in order to execute the printing process, and printing is performed when it is a starting position of the plate discharging process for peeling the used stencil sheet from the printing plate cylinder. Processing and plate removal processing can be performed appropriately.

1 is a schematic configuration diagram of a stencil printing apparatus according to an embodiment of the present invention. FIG. 2 is a rear view around the printing plate cylinder of the stencil printing apparatus.

"First embodiment of the present invention"
1 and 2 show an embodiment of a stencil printing apparatus according to the present invention, which will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram of the stencil printing apparatus I. For convenience of explanation, the upstream side (conveyance start side) in the conveyance direction F of the printing paper P is “rear side” and the downstream side in the conveyance direction F of the printing paper ( In the following description, the “conveyance end side” is referred to as “front side”, and the width direction of the printing paper (horizontal direction orthogonal to the printing paper conveyance direction F) is referred to as “left-right direction”.

  The apparatus main body 1 is provided with a paper feeding device 2 at the rear end, a paper discharge device 3 at the front end, and an image reading device 4 at the upper side.

  In the apparatus main body 1, a printing unit 5 is provided in an approximately middle part in the front-rear direction, a plate making device 6 is provided on the upper rear side of the printing unit 5, and a plate discharging device 7 is provided on the upper front side of the printing unit 5. Is provided.

  The printing unit 5 is inscribed with the ink supply roller 10 and is driven to rotate in the direction of arrow R1 by the drive unit 9, and the vertical movement of the printing plate cylinder 11 facing the printing plate cylinder 11 so that it can be pressed from below. A possible pressing roller 12 is provided. A squeegee roller 19 is in rolling contact with the ink supply roller 10. An ink reservoir 40 is formed at the rolling contact portion between the ink supply roller 10 and the squeegee roller 19. An ink supply pipe 55 is provided above the ink reservoir 40. The ink supply pipe 55 is a pipe that sends ink in an ink bottle (not shown) to above the ink reservoir 40 inside the printing plate cylinder 11.

The printing plate cylinder 11 includes a barrel portion 20 formed by rolling a net of stainless steel or resin fibers into a cylindrical shape, and a pair of flanges (not shown) that are respectively fitted to both ends of the barrel portion 20. And a clamp 54 that is provided between the flanges and clamps the leading end of the stencil sheet N.

Except for the position where the clamp 54 is installed, a large number of ink passage holes (not shown) are formed in the peripheral wall of the body portion 20. A mesh-like screen 24 is wound around the outer periphery of the barrel portion 20 in the range where the ink passage hole is formed in the barrel portion 20. A pair of end plates 26 extending in the left-right direction of the body portion 20 are provided at both ends of the screen 24 in the circumferential direction. The end plate 26 is fixed to the both ends of the circumferential direction with double-sided tape so that no positional deviation occurs in the left-right direction with respect to the screen 24. Further, the end plate 26 can be prevented from being displaced by using a high friction member instead of the double-sided tape because of ease of manufacture. Examples of the high friction member include synthetic rubber, natural rubber, synthetic resin, or natural resin.

A plate-making sheet (stencil sheet) N made by the plate-making apparatus 6 is wound around the outer periphery of the screen 24. The front end portion of the stencil sheet N in the rotation direction R1 is sandwiched and fixed to the body portion 20 of the printing plate cylinder 11 by a clamp 54. Although not shown, the printing plate cylinder 11 is linked to a drive unit 9 including a drive motor via an appropriate power transmission mechanism.

  The image reading device 4 reads an image of a document placed on a glass document table (not shown) and generates image data. The image data may be received from an external computer.

The plate making apparatus 6 includes a mounting portion 15 for the master roll 13 and a thermal head 14. The master roll 13 is formed by winding a stencil sheet N in a roll shape. The thermal head 14 makes a plate on the stencil sheet N drawn from the master roll 13 of the mounting unit 15 based on the image data generated by the image reading device 4. The stencil sheet N thus made is sandwiched between clamps 54 and wound around a printing plate cylinder 11 that is rotated by driving of the drive unit 9. Further, the plate making apparatus 6 includes a plate arrival detecting unit 29. The stencil detection unit 29 is composed of an optical sensor that detects the presence or absence of the stencil sheet N sent from the thermal head 14 to the stencil sheet conveyance roller 30, and from this to the printing plate cylinder 11 of the stencil sheet N that has been made. Detects the occurrence of defective printing. As the defective plate, the stencil sheet N is not conveyed correctly by the platen roller 27 or the stencil sheet conveying roller 30, the stencil sheet N is not properly clamped by the clamp 54, the double wrapping in the state in which the stencil sheet N remains, and the stencil plate. The shortage of the base paper N is mentioned. Further, although not shown in the drawing, when the master roll 13 mounted on the mounting unit 15 is removed as the plate-detecting unit, it is detected that the master roll 13 of the mounting unit 15 has been replaced and is detected as a plate-forming defect. May be. Further, because of the mounting of the new master roll 13 on the mounting portion 15, it may be detected that there is a plate-forming defect by detecting this when the mounting portion 15 and its surroundings are opened and closed.

  The plate discharge device 7 is provided with a drawing roller 16 and a winding roller 17 in a plate discharging box 42, removes the used stencil sheet N wound around the printing plate cylinder 11, and uses the drawing roller 16 to discharge the plate box. 42 is drawn into the inside of the paper 42 and taken up as a discharge roll by the take-up roller 17. The stencil box 42 collects the used stencil sheet N.

Further, the plate removal device 7 includes a plate removal detection unit 35 and an open / close detection unit 36. The stencil detection unit 35 detects the presence or absence of the stencil sheet N sent from the drawing roller 16 to the take-up roller 17, and detects the occurrence of defective stencil printing from the stencil sheet 11 for printing. Examples of the defective plate removal include a bad peeling of the stencil sheet N from the clamp 54, a bad drawing by the drawing roller 16, and a bad winding to the winding roller 17. Further, although not shown in the drawing, as the stencil detection unit, it is detected that all or a part of the used stencil sheet N remains in the printing plate cylinder 11 and cannot be recovered to the stencil discharge device 7, and this case is detected as defective stencil. You may judge. The open / close detection unit 36 detects the opening / closing operation of the discharge box 42 that collects the used stencil sheet N that is performed when the discharge box 42 is full or when some trouble occurs.

  A pair of upper and lower timing rollers 18, 18 are arranged near the rear part of the printing unit 5, and the timing rollers 18, 18 rotate at an appropriate timing in synchronization with the drive of the printing plate cylinder 11 of the printing unit 5. The printing paper P is sent to the printing unit 5. Further, a peeling claw 68 and a blow fan 67 are disposed in the vicinity of the front portion of the printing unit 5 so that the printed printing paper P is peeled from the printing plate cylinder 11.

  At the front end of the sheet feeding device 2, a sheet feeding roller 31 and a separating plate 32 are disposed so that the printing sheets P stacked on the sheet feeding table 33 are supplied one by one from the top. .

  The paper discharge device 3 includes a paper discharge belt 21, a fan 22, and a paper tray 23. The paper P on the paper discharge belt 21 is attracted to the paper discharge belt 21 by the fan 22, and the paper tray 23. It is designed to discharge upward.

In the conveyance path of the printing paper P from the paper feeding device 2 to the paper discharge device 3, a paper conveyance detection unit 66 including optical sensors that detect the presence or absence of the printing paper P is provided at a plurality of appropriate locations. The paper conveyance detection unit 66 detects the occurrence of a conveyance failure of the printing paper P by detecting the presence or absence of the printing paper P at an appropriate location on the conveyance path.

  In the present embodiment, a rotation position detector 56 and an encoder 57 are provided as devices for detecting the rotation phase position of the printing plate cylinder 11. Both the rotational position detector 56 and the encoder 57 are electrically connected to a controller 50 described later. The rotational position detector 56 is provided outside the innermost part of the printing plate cylinder 11.

FIG. 2 is a rear view of the printing plate cylinder 11, the pressing roller 12, the rotational position detection unit 56, the encoder 57, and the driving unit 9. In FIG. 2, unlike FIG. 1, the right side of the printing plate cylinder 11 is the rear side, and the left side is the front side. The printing plate cylinder 11 rotates clockwise R1. The rotational position detection unit 56 includes, for example, an optical sensor 44 in which a light emitting element and a light receiving element face each other at a predetermined interval in the radial direction, and an arc-shaped light shielding member 45 that rotates coaxially with the printing plate cylinder 11. Prepare.

The rotational position detection unit 56 includes a reference position detection unit 80 and a plate position detection unit 81. The reference position detection unit 80 detects whether or not the printing plate cylinder 11 is located at a predetermined reference position in the rotation direction R1. 2, the reference position edge V, which is one end of the light shielding member 45, is the installation position of the optical sensor 44 when the printing plate cylinder 11 is rotated clockwise R1. The rotational phase position at which the sensor 44 changes from light to light shielding member 45. The reference position coincides with the stop position at which the printing plate cylinder 11 is stopped after the required number of prints are completed. The reference position is a plate discharge start position at which the plate stencil sheet N starts to be discharged from the printing plate cylinder 11.

Further, the reference position is a position where the printing plate cylinder 11 is pulled out from the apparatus main body 1 and the attaching / detaching operation for mounting the printing plate cylinder 11 to the apparatus main body 1 is performed. The stencil printing apparatus I includes an attachment / detachment detection unit 46 that detects an attachment / detachment operation of the printing plate cylinder 11 with respect to the apparatus body 1.

The plate position detection unit 81 detects whether or not the printing plate cylinder 11 is located at the plate position. The landing position is a position indicated by a two-dot chain line in which the printing plate cylinder 11 is rotated about 90 ° clockwise from a reference position indicated by a solid line in FIG. The plate position is a rotational phase position where the sensor 44 detects the plate position edge C, which is the other end of the light shielding member 45, and changes from light shielding to light passing. The reference position and the landing position are stored in the control unit 50, respectively.

The encoder 57 is connected to the drive shaft 60 of the drive motor of the drive unit 9 of the printing plate cylinder 11. The encoder 57 uses the phase position of the printing plate cylinder 11 detected by the reference position detector 80 as a reference, that is, sets the pulse count start point, and reads the notch of the encoder 57 with the optical sensor 48 for printing. By counting the rotation of the plate cylinder 11 with a pulse, the rotation angle from the reference phase position of the printing plate cylinder 11 at an arbitrary rotation position is detected and output to the control unit 50.

The stencil printing apparatus I includes a defect detection unit 53 that detects a defect related to at least one of the printing paper P and the stencil sheet N around the printing plate cylinder 11. The defect detection unit 53 includes the paper conveyance detection unit 66, the plate arrival detection unit 29, and the plate discharge detection unit 35 described above. Then, the defect detection unit 53 is caused by the conveyance failure of the printing paper P by the paper conveyance detection unit 66, the plate-making defect of the stencil sheet N made by the plate-making detection unit 29 on the printing plate cylinder 11, and the plate discharge detection unit 35. It detects at least one defect of defective printing of the used stencil sheet N from the printing cylinder 11.

When the defect detection unit 53 starts the printing process or the plate making process after the defect detection unit 53 detects a defect related to at least one of the printing paper P and the stencil sheet N, the control position detection unit 80 determines that the printing plate cylinder 11 When it is detected that the printing plate cylinder 11 is not located at the reference position, the drive unit is controlled to execute the printing process or the plate making process after the printing plate cylinder 11 is rotated to the reference position. Further, when the control unit 6 starts the printing process or the plate making process after the opening / closing detection unit 36 detects the opening / closing operation of the discharge box 42, the reference position detection unit 80 causes the printing plate cylinder 11 to be positioned at the reference position. When it is detected that the printing plate cylinder 11 has not been rotated, the drive unit 9 is controlled to execute the printing process or the plate making process after the printing plate cylinder 11 is rotated to the reference position. When the control unit 6 starts the printing process or the plate making process after the attachment / detachment detection unit 46 detects the attachment / detachment operation of the printing plate cylinder 11, the reference position detection unit 80 sets the printing plate cylinder 11 to the reference position. When it is detected that it is not positioned, the drive unit 9 is controlled to execute the printing process or the plate making process after rotating the printing plate cylinder 11 to the reference position.

  The basic operation of the stencil printing apparatus I will be described. When a document is set on the image reading device 4 and a plate making key (not shown) is pressed, an image reading process is first executed. The image reading device 4 optically reads a document by an image sensor such as a CCD and converts it into an electric signal. At the same time as the image reading process, a plate discharging process is executed, the clamp 54 is opened by an opening / closing device (not shown), and the used stencil sheet N wound around the outer periphery of the printing plate cylinder 11 is printed as the drive unit 9 is driven. When the printing plate cylinder 11 rotates, the printing plate cylinder 11 is peeled off from the printing plate cylinder 11 by the drawing roller 16 and is taken up and collected by the winding roller 17.

After the stencil sheet N is collected into the discharge box 42, the printing plate cylinder 11 is rotated counterclockwise in FIG. When the printing plate cylinder 11 is located at the landing position, the sensor 44 shown in FIG. 2 detects the landing position edge C and changes from light shielding to passage. From this, the control unit 6 determines that the plate position detecting unit 81 has detected that the printing plate cylinder 11 is located at the plate position, stops the driving unit 9, and attaches the printing plate cylinder 11. Stop at the plate position.

In accordance with the information read by the image reading device 4 and converted into an electrical signal, a number of heating elements of the thermal head 14 generate heat selectively, and an image is punched on the stencil sheet N to make a platen roller 27. The stencil sheet N after the plate making is sequentially conveyed to the downstream side by the rotation of the roller 30.

Based on the number of steps of a stepping motor as a drive source for rotationally driving the platen roller 27 and the base paper transport roller 30, the clamp 54 in which the leading end of the stencil sheet N that has been made is in a plate-making standby state in which it is widened. When the control unit 6 determines that it has arrived, the clamp 54 is closed by an opening / closing device (not shown), whereby the leading end of the stencil sheet N that has been subjected to pre-making is held between the clamps 54.

Then, the printing plate cylinder 11 is rotated counterclockwise in FIG. 1 by the drive of the driving unit 9, and the stencil sheet N having been subjected to the plate making is sequentially wound around the outer periphery of the printing plate cylinder 11 from the front end portion. When the control unit 6 determines that the perforating plate making on the stencil sheet N for one plate has been completed based on the number of steps of the stepping motor or the like, the rotation of the platen roller 27 and the stencil transport roller 30 is stopped, and the stencil sheet N that has been made is made. The rear end is cut by the cutting tool 28. As a result, the stencil sheet N having been subjected to plate making is separated from the master roll 13, and the rear end of the stencil sheet N is mounted on the printing plate cylinder 11 as the printing plate cylinder 11 is further rotated. The printing plate cylinder 11 on which the stencil sheet N is mounted is stopped at the reference position when the drive of the drive unit 9 is controlled by the control unit 6.

Thereafter, one sheet of printing paper P is fed from the paper feeding device 2 to the printing unit 5, and ink is applied from the inner peripheral surface of the printing plate cylinder 11 to the stencil stencil sheet N on the outer peripheral surface of the printing plate cylinder 11. , And the printing plate cylinder 11 is rotated by driving of the drive unit 9, and a printing process with a plate is performed in which the stencil sheet N is brought into close contact with the outer peripheral surface of the printing plate cylinder 11. By this printing with a plate, the printing paper P adhered to the outer peripheral surface of the printing plate cylinder 11 via the screen 24 and the stencil sheet N is peeled from the printing plate cylinder 11 by the peeling claw 68 and the blow fan 67, and the ink Is dried and discharged by the paper discharge device 3.

After the plate printing process is completed, the user confirms the image quality and print image position of the plate printed material, and presses a necessary amount of a test print key (not shown) according to the result, thereby performing appropriate test printing. Then, when the user presses the start key after entering the number of regular prints required by the user using a numeric keypad (not shown), the paper feed roller 31, the timing roller 18, the printing plate cylinder 11, the pressure roller 12, the ink roller 10, the squeegee. The roller 19, the ink pump, the blow fan 67, the paper discharge belt 21, and the fan 22 are appropriately driven to perform the printing process.

In this printing process, when the upper driven timing roller 18 is in contact with the lower driving timing roller 18 in FIG. 1, the printing paper is fed from the paper feeding device 2 by the rotation of the paper feeding roller 31. P is separated one by one and conveyed forward. Thereafter, the timing rollers 18 and 18 start to rotate after some time. Due to this delay in the start of rotation, the front end of the printing paper P is bent, and the entire front edge of the printing paper P abuts against the tangent line of the pair of upper and lower timing rollers 18 and 18 so that the printing paper P is printed. The plate cylinder 11 is conveyed straight.

  When the printing paper P is sent forward by the rotation of the timing rollers 18 and 18 and the front end of the printing paper P reaches just below the printing plate cylinder 11, the timing rollers 18 and 18 stop rotating and the upper timing roller 18. Is separated from the lower timing roller 18, and the holding state in which the upper and lower timing rollers 18, 18 are in contact with each other is released. At the same time, the pressing roller 12 moves toward the printing plate cylinder 11 and presses the printing paper P against the surface of the printing plate cylinder 11. Further, at a predetermined timing, the drive unit 9 is driven, the printing plate cylinder 11 starts to rotate from the reference position, and the printing paper P is conveyed while being sandwiched between the printing plate cylinder 11 and the pressing roller 12. Then, printing on the printing paper P is performed. After the printing is finished, the pressing roller 12 is separated from the printing plate cylinder 11, and the printed printing paper P is peeled off from the printing plate cylinder 11 by the peeling claw 66 and the blow fan 67, and is placed on the discharge belt 21 by the fan 22. It is adsorbed and discharged onto the paper tray 23.

When printing on the set number of printing sheets 2 is completed, all the steps of the printing operation are completed. At this time, the control unit 6 stops the printing plate cylinder 11 at the reference position by stopping the driving unit 9 based on the detection of the reference position edge V by the reference position detection unit 80.

  While the printing plate cylinder 11 is rotating, the printing plate cylinder 11 may stop at a position other than the reference position, which is the original stop position, for some reason. For example, when the printing plate cylinder 11 stops urgently due to the occurrence of a conveyance failure of the printing paper P in the conveyance path, or after that, for printing manually to remove the printing paper P causing the jam from the conveyance path For example, when the plate cylinder 11 is rotated. Also, power failure, stop operation by the user during the printing process or the plate making process, defective plate-making of the stencil sheet N made on the printing plate cylinder 11, defective printing of the used stencil sheet N from the printing plate cylinder 11 For example, the printing plate cylinder 11 may stop at a position other than the reference position. Further, when the user opens and closes the plate release box 42, or when the printing plate cylinder 11 is removed from the apparatus main body 1, the user manually rotates the printing plate cylinder 11, due to its own weight or for some other reason. The printing plate cylinder 11 may be displaced from the reference position. In such a case, the control unit 6 may not be able to properly grasp where the printing plate cylinder 11 is located, and the control unit 6 stops the printing plate cylinder 11 at the reference position. In some cases, the printing plate cylinder 11 may actually stop at a position different from the reference date position.

Such rotation of the printing plate cylinder 11 due to manual operation or its own weight can be grasped based on the detection results of the defect detection unit 53, the open / close detection unit 36 or the attachment / detachment detection unit 46. The control unit 6 generates a defect in the printing paper or stencil sheet by the defect detection unit 53, opens / closes the discharge box by the opening / closing detection unit 36, or attaches / detaches the printing plate cylinder 11 from the apparatus main body 1 by the attachment / detachment detection unit 46. When at least one of the operations is detected, the control unit 6 determines that the printing plate cylinder when the reference position detection unit 81 detects that the printing plate cylinder 11 is not located at the reference position. The drive of the drive unit 9 is controlled so that the printing process or the plate-making process is executed after rotating 11 to the reference position. Then, the printing plate cylinder 11 is rotated to the reference position by driving the drive unit 9 and then the printing process or the plate making process is executed.

The control unit 6 generates a defect in the printing paper or stencil sheet by the defect detection unit 53, an opening / closing operation of the discharge box by the opening / closing detection unit 36, or the printing plate cylinder 11 from the apparatus main body 1 by the attachment / detachment detection unit 46. When at least one of the attachment / detachment operations is detected, even if the reference position detection unit 81 does not necessarily detect that the printing plate cylinder 11 is not located at the reference position, it is natural. Assuming that the printing plate cylinder 11 is at a position deviated from the reference position, the drive unit 9 is always controlled to rotate the printing plate cylinder 11 to the reference position, and then the printing process or the plate making process is executed. May be. As a result, the control method becomes easier and the printing plate cylinder 11 can be reliably positioned at the reference position.

In addition to the above, it is also possible to determine whether or not the printing plate cylinder 11 is located at the reference position based on the detection result of the encoder 57. That is, after the printing plate cylinder 11 stops at the reference position, the control unit 6 monitors the rotation of the printing plate cylinder 11 by the encoder 57. When there is a change in the detection result of the encoder 57, the control unit 6 determines that the printing plate cylinder 11 has been rotated to a position shifted from the reference position. By performing such monitoring by the encoder 57, the position of the printing plate cylinder 11 can be easily grasped when the energized state is continued.

As described above, when there is a possibility that the printing plate cylinder 11 is stopped at a position different from the reference position, the control unit 6 requests the user to start either the printing process or the plate making process. If there is, the drive unit 9 is once driven and the printing plate cylinder 11 is rotated before the start of the printing process or the plate making process. When the reference position detection unit 56 detects that the printing plate cylinder 11 is located at the reference position, the control unit 6 stops the driving unit 9 and stops the printing plate cylinder 11 at the reference position. .

Accordingly, the control unit 6 can position the printing plate cylinder 11 at the reference position. Therefore, since the printing plate cylinder 11 starts to rotate from a position different from the reference position, it is possible to prevent the problem that the printing process and the plate making process cannot be performed properly.

On the other hand, the reference position detection unit 80 detects that the printing plate cylinder 11 is stopped at the reference position by executing printing processing, plate making processing, and other various controls, which do not correspond to the above various states. In this case, the control unit 6 executes the printing process or the plate making process without driving the driving unit 9 to rotate the printing plate cylinder 11 to the reference position.

N stencil sheet, 1 main body, 6 control unit, 9 driving unit, 11 printing plate cylinder, 6 open / close detection unit, 42 plate making box, 44 sensor, 45 light shielding member, 46 attachment / detachment detection unit, 53 defect detection unit, 80 standard Position detector.

Claims (6)

A printing cylinder on which stencil paper is wound,
A drive unit for rotationally driving the printing plate cylinder;
A reference position detector for detecting whether or not the printing plate cylinder is positioned at a predetermined reference position in the rotation direction;
A fault detection unit for detecting a fault related to at least one of printing paper and stencil paper around the printing plate cylinder;
When the defect detection unit starts the printing process or the plate making process after detecting a defect related to at least one of the printing paper and the stencil sheet, the reference position detection unit detects that the printing plate cylinder is located at the reference position. A stencil printing apparatus comprising: a control unit that controls a drive unit to execute a printing process or a plate making process after rotating the printing plate cylinder to the reference position when it is detected that the printing plate cylinder is not present. The defect detection unit detects at least one of the following problems: conveyance failure of printing paper, imperfection of plate-making stencil sheet on the printing plate cylinder, and defective printing of used stencil sheet from the printing plate cylinder The stencil printing apparatus according to claim 1. A printing cylinder on which stencil paper is wound,
A drive unit for rotationally driving the printing plate cylinder;
A reference position detector for detecting whether or not the printing plate cylinder is positioned at a predetermined reference position in the rotation direction;
An open / close detection unit for detecting the open / close operation of the stencil box for collecting used stencil paper,
When the opening / closing detection unit starts the printing process or the plate making process after detecting the opening / closing operation of the plate ejection box, the reference position detection unit detects that the printing plate cylinder is not located at the reference position. In this case, a stencil printing apparatus comprising: a control unit that controls a drive unit to execute a printing process or a plate making process after rotating the printing plate cylinder to the reference position. A printing cylinder on which stencil paper is wound,
A drive unit for rotationally driving the printing plate cylinder;
A reference position detector for detecting whether or not the printing plate cylinder is positioned at a predetermined reference position in the rotation direction;
An attachment / detachment detection unit for detecting an attachment / detachment operation of the printing plate cylinder to the apparatus main body;
When the detachment detection unit starts the printing process or the plate making process after detecting the detachment operation of the printing plate cylinder, the reference position detection unit indicates that the printing plate cylinder is not located at the reference position. A stencil printing apparatus comprising: a control unit that controls a drive unit to execute a printing process or a plate making process after rotating the printing plate cylinder to the reference position when detected. The reference position detection unit includes an optical sensor and a light shielding member,
The stencil printing apparatus according to claim 1, wherein the reference position is detected by the sensor detecting an edge of the light shielding member. The reference position is a position where rotation of a printing plate cylinder is started in order to execute a printing process, and a starting position of a plate discharging process where the used stencil sheet is separated from the printing plate cylinder. The stencil printing apparatus according to claim 5.

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