JP2019038131A - Printing apparatus and printing pressure control method - Google Patents

Abstract

The present invention relates to a printing apparatus and printing pressure control method for performing stencil printing, and suppresses excessive transfer of ink floating above a perforation of a master plate to a printing sheet by idle rotation of a printing drum and prevents set-off. A printing drum that is wound with a stencil sheet that has been stenciled and rotated while supplying ink to the stencil sheet, and a stencil sheet that is wound around the outer peripheral surface of the printing drum is pressed against the stencil sheet from within the printing drum. In a printing apparatus comprising pressure contact means for printing on printing paper by supplying ink to stencil paper and idle rotation means for idly rotating the printing drum for a set number of idle rotations, the printing pressure control means 310 is The press contact means controls the printing pressure, which is the pressure that presses the printing paper against the stencil sheet, according to the number of idling revolutions set by the drum idling speed setting means 311. Further, the printing pressure control unit 310 further controls the printing pressure according to the rotation speed set for the printing drum. The printing pressure control unit 310 sets the controlled printing pressure in the printing pressure adjusting motor 124 that is a pressing unit. [Selection] Figure 1

Description

  The present invention relates to a printing apparatus that performs stencil printing and a printing pressure control method.

  Conventionally, a master head is created by driving a thermal head or the like based on image data obtained by reading a document with a scanner or the like, and melt-drilling a stencil sheet to create a master plate, and the created master plate is used as a printing drum. Various stencil printing apparatuses have been proposed in which printing is performed by winding ink around a printing drum, supplying ink from the inside of the printing drum, and transferring the ink to printing paper using a roller or the like. In a stencil printing machine, when a printed matter is discharged at a high speed, depending on the paper, the ink of the printed matter does not dry sufficiently and the ink moves to the back side of the next printed matter and gets dirty, so-called `` setback '' phenomenon occurs. There are things to do.

  Therefore, conventionally, a technique is known in which a time interval until the next printed material is discharged is adjusted to make time for the ink to dry and to prevent set-off (for example, Patent Document 1). In this technique, the interval until the next printed matter is discharged is adjusted by idling the printing drum or by stopping the printing drum rotation for a certain period of time. Alternatively, the degree of set-off can be adjusted by designating the intermittent printing time.

JP-A-3-193383

  However, in the above-described prior art, in which the printed paper discharge time interval is adjusted by idling the printing drum, the ink floats from the perforated portion of the master plate wound around the printing drum by the centrifugal force of idling, and the printing paper is The amount of ink to be transferred becomes excessive, whereby the set-off is deteriorated, and the effect of skip printing is not sufficiently obtained. Further, as the number of drum rotations increases, the amount of ink floating from the perforated portion of the master plate increases, and the set-off deteriorates.

  On the other hand, in the above-described prior art in which the print discharge time interval is adjusted by stopping the rotation of the printing drum for a certain time, the rotation speed of the printing drum is accelerated from a low speed in the initial period from the stop state of the printing drum to the start of rotation. When the rotational speed of the printing drum is low, the contact time between the printing drum and the printing paper is long, and it is not preferable because settling occurs due to excessive transfer of ink.

  SUMMARY OF THE INVENTION An object of the present invention is to suppress excessive transfer of ink that has emerged from punching of a master plate to a printing sheet due to idle rotation of a printing drum and prevent set-off.

  In one example, the stencil sheet that has been stenciled is wound around the printing drum that rotates while supplying ink to the stencil sheet, and the stencil sheet that is wound around the outer peripheral surface of the printing drum is pressed against the stencil sheet so that the inside of the printing drum The pressure contact means for printing on the printing paper by supplying ink to the stencil sheet, the idle rotation means for idly rotating the printing drum for the set number of idle rotations, and the pressure contact means according to the number of idle rotations. And a printing pressure control means for controlling a printing pressure that is a pressure for pressing the printing paper.

  According to the present invention, it is possible to suppress excessive transfer of the ink that has been lifted from the perforations of the master plate to the printing paper due to the idling rotation of the printing drum, and to prevent set-off.

FIG. 2 is a diagram illustrating an example of a block diagram of a system that controls a printing apparatus. It is a figure which shows the data structural example of a printing pressure value storage table. It is a figure which shows the example of the printing mechanism of a printing apparatus. It is a figure which shows the example of the printing pressure control mechanism of a printing apparatus. 6 is a flowchart illustrating an example of a printing pressure control operation of the printing apparatus.

  Hereinafter, embodiments of a printing apparatus and a printing pressure control method thereof according to the present invention (hereinafter, “this embodiment”) will be described in detail with reference to the drawings. In this embodiment, a stencil sheet made by stencil is wound and rotated while supplying ink to the stencil sheet, and the stencil sheet wound around the outer peripheral surface of the printing drum is pressed against the stencil sheet so that the printing sheet And a pressure contact means for printing on the printing paper by supplying ink to the stencil paper. In addition, the present embodiment includes an idling unit that idly rotates the printing drum by a set number of idling rotations in order to prevent settling on the printing paper.

  In such a printing apparatus, when the number of idle rotations of the printing drum is changed in order to prevent set-off, the applicant of the present invention uses the press contact means to print the stencil sheet on the stencil sheet under the respective idle rotation times. It was found that the degree of set-off can be minimized by adjusting the printing pressure, which is the pressure for press-contacting. In addition, even when the rotation speed of the printing drum is changed in order to adjust the printing density or the printing speed, the applicant of the present invention similarly adjusts the printing pressure based on the respective rotation speeds. It was found that can be minimized.

  FIG. 1 is a block diagram of a system for controlling a printing apparatus based on the above knowledge. 1, the printing apparatus 1 includes a control unit 301, a printer engine 302, an external storage device 303, a document table 304 including a reading unit, an operation panel 305, a portable recording medium interface 306, and a communication interface 307. Are connected to each other by a bus 308. The control unit 301 further includes a printing pressure control unit 310, a drum idling number setting unit 311, a printing speed setting unit 312, and a skip printing selection unit 313.

  In the configuration of the printing apparatus 1 in FIG. 1, the control unit 301 is a dedicated hardware device that realizes the functions of the units 310 to 313 or a processor that executes a control program stored in a memory (not shown).

  A printing speed setting unit 312 executed by the control unit 301 causes the user to set a printing speed corresponding to the printing density via the operation panel 305.

  The skip print selection unit 313 executed by the control unit 301 causes the user to select skip print that idles the print drum in order to prevent set-off via the operation panel 305. In addition, the drum idle rotation number setting unit 311 allows the user to set the number of idle rotations of the print drum when skip printing is selected via the operation panel 305.

  The printing pressure control unit 310 is arranged on the outer peripheral surface of the printing drum according to the number of idling rotations of the printing drum set by the drum idling number setting unit 311 when skip printing is selected by the skip printing selection unit 313. The printing pressure, which is a pressure contact pressure in a press roller (pressing means), which will be described later, is controlled by pressing the printing paper against the wound stencil paper and supplying ink from the printing drum to the stencil paper. . The printing pressure control unit 310 controls the printing pressure according to the rotation speed set for the printing drum by the printing speed setting unit 312. The printing pressure control means 310 sets the printing pressure controlled in this way in a printing pressure adjusting motor 124 (see FIG. 4) described later.

  The printing pressure adjusting motor 124 controls the press contact pressure of a press roller, which will be described later, to be the printing pressure set by the printing pressure control unit 310. This detailed operation will be described later.

  Specifically, the printing pressure control unit 310 stores the printing pressure value storage table 200 illustrated in FIG. 2 in a built-in ROM (read only memory) or a non-volatile memory (not shown). The printing pressure value storage table 200 stores an optimum printing pressure value (unit: kgf) for each combination of a plurality of values of the number of idling rotations of the printing drum and a plurality of values of the rotation speed of the printing drum. In the example of FIG. 2, the number of idling rotations (unit: times) is classified into any of 0, 1-2, 3-4, 5-6, 7-8, and 9 or more. . Further, the rotation speed (unit: rpm) is classified into one of 130 rpm, 100 rpm, and 60 rpm. For each combination of the number of idling rotations and the rotation speed, the printing pressure for each combination is set so that the printing pressure decreases as the number of idling rotations increases, and the printing pressure increases as the rotation speed increases.

  For example, when the rotational speed is 130 rpm, the printing pressure is set to the maximum value of 17 kgf when the number of idling revolutions is 0, and the printing pressure is set to 7 kgf when the number of idling revolutions is 9 or more. In each case where the rotation speed is 100 rpm or 60 rpm, the tendency that the printing pressure is set to decrease as the number of idling rotations increases is the same as in the case where the rotation speed is 130 rpm. For example, when the number of idling revolutions is 0, when the rotational speed is 130 rpm, the maximum printing pressure is set to 17 kgf, and when the rotational speed is 60 rpm, the printing pressure is set to 13 kgf. Even when the number of idle rotations is greater than 0, the tendency that the printing pressure increases as the rotation speed increases is the same as when the number of idle rotations is 0.

  The printing pressure control means 310 exemplifies the printing pressure value corresponding to the combination of the number of idling revolutions of the printing drum set by the drum idling speed setting means 311 and the rotation speed set by the printing speed setting means 312 in FIG. Read out from the printing pressure value storage table 200. Then, the printing pressure control unit 310 sets a printing pressure corresponding to the read printing pressure value in a printing pressure adjusting motor 124 (see FIG. 4) described later.

  Here, as the number of idling revolutions of the printing drum increases, the ink floats from the perforated portion of the master plate wound around the printing drum by the centrifugal force of idling rotation, and the amount of ink transferred to the printing paper becomes excessive. The set-off deteriorates and the skip printing effect cannot be obtained sufficiently. Therefore, in the present embodiment, the press operation pressure applied to the printing drum by the press roller is increased as the number of idle rotations of the printing drum increases or the drum rotation speed during printing decreases as a result of the control operation of the printing pressure control unit 310 described above. By controlling the printing pressure to be small, it is possible to minimize the degree of setback to the printing paper.

  In FIG. 1, when a document is placed on the document table 304, the control unit 301 controls a reading unit (see the reading unit 10 in FIG. 3) disposed below the document table 304, thereby controlling the document table 304. Scan and read a document placed on the glass. The control unit 301 generates image data for plate making printing based on the read document data, and outputs the image data to the printer engine 302. The printer engine 302 controls a paper feeding mechanism and a conveyance mechanism (not shown), and executes plate making for generating stencil paper from image data for plate making printing input from the control unit 301. Thereafter, the control unit 301 controls the printer engine 302 to execute printing on the printing paper using the stencil sheet. Finally, the printer engine 302 controls a paper transport mechanism and a paper discharge mechanism (not shown), and discharges the print paper on which printing has been completed.

  The external storage device 303 is, for example, a hard disk storage device or a semiconductor disk device, and stores various print control programs executed by the control unit 301, document data, image data for printing, and the like.

  The operation panel 305 is, for example, a touch panel and a liquid crystal display device for the user to set skip printing, set the number of idling rotations during skip printing, and set the printing speed.

  The communication interface 307 relays printing-related data transmission / reception between the network and the control unit 301 when the printing apparatus 1 is connected to a local area network (not shown) or the like.

  The portable recording medium interface 306 accommodates a portable recording medium 309 such as a USB memory, an SD card memory, a compact flash (registered trademark) memory, a CD-ROM, a DVD, and an optical disk. Have a role.

  The printing apparatus 1 according to the present embodiment may be realized by a processor executing a printing pressure control program that realizes various functions of the control unit 301. For example, the control program may be an external storage device 303 or a portable recording medium. 309 may be recorded and distributed, or may be acquired from the network by the communication interface 307.

  FIG. 2 is a diagram illustrating an example of the printing mechanism of the printing apparatus 1. As shown in FIG. 3, the printing apparatus 1 includes a reading unit 10 that reads an image of a document, a plate making unit 20 that performs plate making processing on the stencil sheet M based on image information read by the reading unit 10, and a plate making unit 20. A printing unit 30 that prints on printing paper using the stencil sheet M that has been made, a paper feeding unit 40 that feeds the printing paper to the printing unit 30, a paper discharge unit 50 that discharges printed printing paper, and a used paper The stencil sheet M is discarded.

  The reading unit 10 disposed below the glass surface of the document table 304 is an image scanner, and includes a line image sensor 12 that reads an image of a document conveyed in the sub-scanning direction and a document feed roller 14. Yes.

  The plate making unit 20 includes a base paper roll unit 21, a plate making unit 22 having a thermal head in which a plurality of heating elements are arranged in a row, base paper feed rollers 23 and 24, base paper guide rollers 25, 26 and 27, and base paper. And a cutter 28. In the plate making unit 20, a stencil sheet M having a predetermined length corresponding to the plate making is fed out from the base paper roll 21, and the plurality of heating elements of the plate making unit 22 individually and selectively generate heat. The stencil sheet M is made by thermal perforation. The pre-made stencil sheet M is cut by a base paper cutter 28 and wound around a printing drum 31.

  The printing unit 30 is an ink having an ink-permeable cylindrical printing drum 31 such as a porous metal plate or a mesh structure, and a squeegee roller 32, a doctor roller 33, and an ink supply pump 35 disposed inside the printing drum 31. A supply device 34 and a press roller 36 are provided. A pre-made stencil sheet M is wound around and mounted on the outer periphery of the drum.

  In the printing apparatus 1, printing ink of a predetermined color is supplied to the inside of the printing drum 31 by the ink supply device 34, and the printing drum 31 is counterclockwise around the center axis line of the printing drum 31 by a rotation driving unit (not shown). The printing drum 31 and the press roller 36 are driven to rotate in the rotation direction and the printing paper P is moved from the left to the right in the drawing by the timing roller 43 at a predetermined timing in synchronization with the rotation of the printing drum 31. The printing paper P is pressed against the pre-made stencil sheet M wound around the outer peripheral surface of the printing drum 31 by the press roller 36, so that the printing paper P has a predetermined width. Stencil printing with color printing ink is performed.

  FIG. 4 is a diagram illustrating an example of the printing pressure control mechanism of the printing apparatus 1. The press roller 36 extends in the axial direction of the printing drum 31 and is supported by the bracket 100 so as to be rotatable around its central axis. The bracket 100 is rotatable by a frame (not shown) which is a fixed member. It is fixedly attached to the press shaft 101 supported by. As a result, the press roller 36 can be displaced in a substantially vertical direction around the press shaft 101, and is pressed against the retracted position separated from the outer peripheral surface of the printing drum 31 and the outer peripheral surface of the printing drum 31. It can move between the operating positions.

  A press drive lever 102 is fixedly mounted on the press shaft 101, and the press shaft 101 supports a press drive plate 103 in a rotatable manner. A hook member 105 is rotatably attached to the press drive plate 103 by a pivot 104, and the hook member 105 is rotationally driven by a solenoid 106 mounted on the press drive plate 103 and selectively selected from the press drive lever 102. The press drive lever 102 and the press drive plate 103 are driven and connected to each other. One end of the first link member 108 is pivotally connected to the end of the press drive plate 103 by a pivot 107. The first link member 108 is formed with elongated holes 109 extending in two directions in the same direction, and the pins 111 of the second link member 110 are engaged with the elongated holes 109. Thus, the first link member 108 and the second link member 110 are connected to each other within the range of the long hole 109 so as to be displaceable in the link length direction, that is, in the substantially vertical direction in FIG.

  A bent flange piece 112 is provided at the lower end of the first link member 108, and an adjustment screw 113 penetrates the bent flange piece 112 so as to be movable in the reciprocating direction of the first link member 108. Yes. A spur gear-like nut member 116 having external teeth 115 via a collar 114 at a position below the bent flange piece portion 112 is screwed to the adjustment screw 113, and this adjusting screw 113 is screwed. One end of a tension coil spring 117 is locked to the upper end of 113. The adjustment screw 113 is prevented from rotating because one end of the tension coil spring 117 is locked to the adjustment screw 113, and moves in the axial direction with respect to the first link member 108 by the rotation of the nut member 116. The tension coil spring 117 is locked to the pin 111 at the other end, and the first link member 108 is located above the second link member 110, in other words, the press drive plate 103 around the press shaft 101 in FIG. In other words, the press roller 36 is urged in the counterclockwise direction, that is, in the direction of pressing the press roller 36 against the outer peripheral surface of the printing drum 31.

  The second link member 110 is pivotally connected to the distal end portion of the cam lever 119 by a pivot 118 at the upper end portion. The cam lever 119 is supported by a support shaft 120 so as to be rotatable from a frame (not shown), and a cam follower roller 121 is rotatably supported by a pivot 118 at a tip portion. The cam follower roller 121 is engaged with a press cam 123 attached to the main shaft 122. The press cam 123 rotates in synchronization with the rotation of the printing drum 31, and when a stencil sheet clamp portion (not shown) provided on the outer peripheral portion of the printing drum 31 is positioned at a rotation position corresponding to the press roller 36, In order to avoid interference between the roller 36 and the stencil sheet clamp portion, a cam profile for positioning the press roller 36 in the retracted position is provided.

  A printing pressure adjusting motor 124 (see FIG. 1) is attached to the bent flange piece 112, and a driving germ wheel 126 is fixedly attached to the output shaft 125 of the printing pressure adjusting motor 124. The drive gear 126 meshes with the external teeth 115 of the nut member 116, and transmits the output shaft rotation of the printing pressure adjusting motor 124 to the nut member 116. In the printing pressure control mechanism shown in FIG. 4, the press cam 123 rotates in the clockwise direction in FIG. 3 by the rotation of the printing drum 31, and this rotation causes the second link member 110 to reciprocate in the substantially vertical direction. The movement is transmitted to the first link member 108 via the tension coil spring 117. When the first link member 108 reciprocates, the press drive plate 103 reciprocates around the press shaft 101, and at this time, the hook member 105 is moved to the engagement position by the solenoid 106 and engaged with the press drive lever 102. As a result, the reciprocating rotation of the press drive plate 103 is transmitted to the press shaft 101, and the press roller 36 swings and displaces in the substantially vertical direction around the press shaft 101 by the reciprocating rotation of the press shaft 101. 36 moves between a retracted position separated from the outer peripheral surface of the printing drum 31 and a pressing action position pressed against the outer peripheral surface of the printing drum 31.

  At this time, the movement of the press roller 36 to the pressing position is transmitted to the first link member 108 while the second link member 110 is pulled up and a tensile force is applied to the tension coil spring 117, and the press drive plate 103 is moved. It is performed by rotating counterclockwise in FIG. 3 about the press shaft 101, and the press roller 36 is pressed against the outer peripheral surface of the printing drum 31 with the printing paper P in between, and the press driving plate 103 The rotation in the counterclockwise direction in FIG. 3 centering on the press shaft 101 is restricted, and the second link member 110 is pulled up further than this state, so that the second link member 110 becomes the first link member 108. In contrast, the tension coil spring 117 is extended. As a result, the press roller 36 is pressed against the outer peripheral surface of the printing drum 31 with the printing paper P sandwiched by the spring force generated by the extension of the tension coil spring 117, and the printing pressure is determined by this spring force.

  When adjusting the printing pressure, the driving gear 126 is rotated by driving the printing pressure adjusting motor 124. The rotation of the drive gear 126 is transmitted to the nut member 116, and the adjustment screw 113 moves in the axial direction with respect to the first link member 108 by the rotation of the nut member 116, and the axial direction of the adjust screw 113 relative to the first link member 108. The position changes. As a result, the engaging portion between the tension coil spring 117 and the adjust screw 113 is displaced in the axial direction with respect to the first link member 108, and the attachment length of the tension coil spring 117 is changed by this displacement, and this attachment load Changes. Due to the change in the mounting load of the tension coil spring 117, the pressure for pressing the press roller 36 against the outer peripheral surface of the printing drum 31 under the action as described above, that is, the printing pressure changes.

  The above-described printing pressure control means 310 in the plate making unit 20 in FIG. 1 sets an appropriate printing pressure for the printing pressure adjusting motor 124.

  The paper feed unit 40 includes a paper feed base 41 on which the print paper P is placed, a pickup roller 42 that picks up the print paper P from the paper feed base 41 one by one, a print drum 31 and a press roller 36. And a timing roller 43 for feeding between the two.

  The paper discharge unit 50 includes a peeling claw 51 that peels the print paper P from the print drum 31, a paper discharge feed belt unit 52, and a paper discharge tray 53 on which the printed print paper P is stacked. .

  The plate discharging unit 60 is provided on one side of the printing unit 30, and the plate discharging box 61 into which the used stencil sheet M peeled off from the printing drum 31 is fed, and the used stencil sheet M is peeled off from the printing drum 31. And a plate discharge roller 62 for feeding into the plate discharge box 61.

  FIG. 5 illustrates a print pressure control process performed by the control unit 301 illustrated in FIG. 1, which is a function of the print pressure control unit 310, the drum idle rotation number setting unit 311, the print speed setting unit 312, and the skip print selection unit 313 illustrated in FIG. It is a flowchart which shows an example. This processing is realized as an operation in which the control unit 301 executes a printing pressure control processing program stored in a memory (not shown).

  In FIG. 5, the control unit 301 first causes the user to set a print speed corresponding to the print density via the operation panel 305 (step S501). This processing corresponds to the function of the printing speed setting unit 312 in FIG.

  Next, the control unit 301 determines whether or not the user has selected skip printing that idles the print drum in order to prevent set-off via the operation panel 305 (step S502). This processing corresponds to the function of the skip print selection unit 313 in FIG.

  When it is determined that the user has selected skip printing (when the determination in step S502 is YES), the control unit 301 causes the user to set the number of idling rotations of the printing drum 31 via the operation panel 305 (step S503). . This processing corresponds to the function of the drum idling number setting means 311 in FIG.

  After step S503, the control unit 301 sets the printing pressure value corresponding to the combination of the number of idling rotations of the printing drum 31 set in step S503 and the rotation speed of the printing drum 31 set in step S501 to the control unit 301. It is read from the printing pressure value storage table 200 illustrated in FIG. 2 stored in an internal memory (not shown). Then, the control unit 301 sets the printing pressure corresponding to the read printing pressure value in the printing pressure adjusting motor 124 in FIG. 4 (step S504). This processing corresponds to a part of the function of the printing pressure control unit 310 in FIG.

  On the other hand, when the control unit 301 determines that the user has not selected skip printing (when the determination in step S502 is NO), the number of idling rotations of the printing drum 31 is zero and the printing drum 31 set in step S501 is determined. The printing pressure value corresponding to the combination of the rotation speeds is read from the printing pressure value storage table 200 illustrated in FIG. 2 stored in a memory (not shown) inside the control unit 301. Then, the control unit 301 sets a printing pressure corresponding to the read printing pressure value in the printing pressure adjusting motor 124 of FIG. 4 (step S505). This processing corresponds to a part of the function of the printing pressure control unit 310 in FIG.

  After the processing in step S504 or S505, when a document is placed on the document table 304, the control unit 301 controls the reading unit 12 in FIG. Scan and read a document placed on the surface. The control unit 301 generates image data for plate making printing based on the read document data, and outputs the image data to the printer engine 302. The printer engine 302 controls the plate making unit 20 shown in FIG. 3 to execute plate making for producing the plate making stencil sheet M from image data for plate making printing input from the control unit 301. Thereafter, the control unit 301 controls the paper feeding unit 40 and the printing unit 30 in FIG. 3 from the printer engine 302 to execute printing on the printing paper using the pre-made stencil sheet M. Finally, the printer engine 302 controls the paper discharge unit 50 to discharge the printing paper on which printing has been completed (step S506). Thereafter, the plate making unit 20 ends the printing pressure control process shown in the flowchart of FIG.

  In the embodiment described above, when control is performed to accelerate from a low speed at the beginning of rotation from the stop state of the print drum, the rotation speed of the print drum increases the contact time between the print drum and the paper. Control may be performed so as to prevent the occurrence of set-off due to excessive ink transfer by controlling the printing pressure to be low during low-speed rotation, and to increase the printing pressure as the speed increases.

  In addition, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention in the implementation stage. Further, the functions executed in the above-described embodiments may be combined as appropriate as possible. The above-described embodiment includes various stages, and various inventions can be extracted by an appropriate combination of a plurality of disclosed constituent elements. For example, even if several constituent requirements are deleted from all the constituent requirements shown in the embodiment, if an effect is obtained, a configuration from which the constituent requirements are deleted can be extracted as an invention.

Regarding the above embodiment, the following additional notes are disclosed.
(Appendix 1)
A printing drum that is wound around a stencil sheet that has been stenciled and rotates while supplying ink to the stencil sheet;
Pressure contact means for printing on the printing paper by pressing the printing paper to the stencil paper wound around the outer peripheral surface of the printing drum and supplying ink from the printing drum to the stencil paper; and
Idle rotation means for idly rotating the printing drum a set number of idle rotations;
A printing pressure control means for controlling a printing pressure, which is a pressure by which the pressure contact means presses the printing paper against the stencil paper according to the number of idling times;
A printing apparatus comprising:
(Appendix 2)
The printing pressure control means further controls the printing pressure according to a rotation speed set for the printing drum.
The printing apparatus according to Supplementary Note 1, wherein
(Appendix 3)
The printing pressure control means includes
A printing pressure value storage table for storing an optimum printing pressure value for each combination of a plurality of values of the number of idling revolutions and a plurality of values of the rotation speed of the printing drum;
A printing pressure value corresponding to a combination of the value of the number of idling rotations set by the idling rotation unit and the value of the rotation speed set for the printing drum is read from the printing pressure value storage table, and the pressing unit Controlling the printing pressure to correspond to the read printing pressure value,
The printing apparatus according to Supplementary Note 1, wherein
(Appendix 4)
Printing is performed on the printing paper by supplying printing ink to the stencil paper from the printing drum by pressing the printing paper on the stencil paper stencil wound around the outer peripheral surface of the rotating printing drum,
When the number of idling rotations is set, the printing drum is idly rotated by the number of idling rotations,
According to the number of idling rotations, the pressure contact means controls a printing pressure which is a pressure for pressing the printing paper against the stencil sheet,
A printing pressure control method.

DESCRIPTION OF SYMBOLS 1 Printing apparatus 10 Reading part 20 Plate making part 30 Printing part 40 Paper feeding part 50 Paper discharge part 60 Paper discharge part 31 Printing drum 32 Squeegee roller 33 Doctor roller 34 Ink supply apparatus 35 Ink supply pump 36 Press roller 124 Electric motor for printing pressure adjustment 301 Control unit 302 Printer engine 310 Printing pressure control means 311 Drum idling number setting means 312 Printing speed setting means 313 Skip printing selection means

Claims (4)

A printing drum that is wound around a stencil sheet that has been stenciled and rotates while supplying ink to the stencil sheet;
Pressure contact means for printing on the printing paper by pressing the printing paper to the stencil paper wound around the outer peripheral surface of the printing drum and supplying ink from the printing drum to the stencil paper; and
Idle rotation means for idly rotating the printing drum a set number of idle rotations;
A printing pressure control means for controlling a printing pressure, which is a pressure at which the pressure contact means presses the printing paper against the stencil paper, according to the number of idling rotations set by the idle rotation means;
A printing apparatus comprising: The printing pressure control means further controls the printing pressure according to a rotation speed set for the printing drum.
The printing apparatus according to claim 1. The printing pressure control means includes
A printing pressure value storage table for storing an optimum printing pressure value for each combination of a plurality of values of the number of idling revolutions and a plurality of values of the rotation speed of the printing drum;
A printing pressure value corresponding to a combination of the value of the number of idling rotations set by the idling rotation unit and the value of the rotation speed set for the printing drum is read from the printing pressure value storage table, and the pressing unit Controlling the printing pressure to correspond to the read printing pressure value,
The printing apparatus according to claim 1. Printing is performed on the printing paper by supplying printing ink to the stencil paper from the printing drum by pressing the printing paper on the stencil paper stencil wound around the outer peripheral surface of the rotating printing drum,
When the number of idling rotations is set, the printing drum is idly rotated by the number of idling rotations,
According to the number of idling rotations, the pressure contact means controls a printing pressure which is a pressure for pressing the printing paper against the stencil sheet,
A printing pressure control method.