JP2016083786A - Rotary screen printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary screen printer by which screen printing is normally performed from the first sheet at printing start, whereby generation of a soilage is suppresses, and further, occurrence of a printing failure is suppressed.SOLUTION: A rotary screen printer is provided with: this machine encoder 229 for detecting a phase of an impression cylinder 100; and a controller which controls a screen cylinder attachment/detachment motor 209A and a squeegee attachment/detachment motor 224A so that a screen printing plate 201A contacts the impression cylinder 100 and a squeegee 221 contacts an inner peripheral surface of the screen printing plate 201A conforming with a timing at which the first sheet reaches a contact portion between the impression cylinder 100 and the screen printing plate 201A on the basis of a phase detected by this machine encoder 229, and controls the squeegee attachment/detachment motor 224A so that operation for attachment of the squeegee 221 onto the inner peripheral surface of the screen printing plate 201A is so performed as to be divided into plural stages.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a rotary screen printing machine that performs printing, coating, and the like by supplying a liquid such as ink or varnish from a hole of a plate material such as a screen to a sheet or web with a squeegee.

  Conventionally, as a printing machine capable of rotary screen printing, there are those disclosed in Patent Documents 1 and 2 below.

JP 2014-100819 A Japanese Patent No. 5337358 JP 2008-120064 A

  However, in the conventional rotary screen printing machine as described above, at the start of printing, the attachment / detachment drive for bringing the screen cylinder into contact with or separating from the impression cylinder and the attachment / detachment drive for bringing the squeegee into contact with or separated from the screen cylinder are performed on the screen plate. In order not to put a load on the pattern part of the screen and to prevent the pattern from being printed on the sheet, it is done using the part without the screen pattern (the notch part of the impression cylinder). (For example, refer to Patent Document 3). The screen cylinder and the squeegee are attached and detached using an air cylinder, and it is difficult to control the speed with high accuracy with a fluid actuator such as an air cylinder. Therefore, the screen cylinder and the squeegee interfere with each other. In order to avoid this, it was necessary to shift the operation timing of each. That is, in the conventional rotary screen printing machine, the screen cylinder and the squeegee cannot be operated at the same time at the notch portion of the impression cylinder.

Therefore, when screen printing is performed, the screen cylinder is brought into contact with the impression cylinder so that the phase of the impression cylinder becomes the phase θ _n at which the first sheet reaches the screen cylinder as shown in FIG. Then, after the screen cylinder makes one rotation, the squeegee is brought into contact with the screen plate of the screen cylinder. However, in this case, since the ink is not pushed out from the screen plate by the squeegee in the first few sheets, several sheets have been burnt paper from the start of printing.

  Further, when the squeegee is attached to the screen plate, the ink is scattered in the screen plate due to an impact load, and the ink film thickness on the plate surface is changed by the scattered ink, which may cause printing failure.

  In view of the above, an object of the present invention is to provide a rotary screen printing machine that suppresses occurrence of scraping paper and further suppresses occurrence of defective printing by performing screen printing normally from the first printing start. .

  A rotary screen printing machine according to a first aspect of the present invention for solving the above-described problems is an impression cylinder that holds and conveys a sheet, a screen plate formed in a cylindrical shape, and is held inside the screen plate. A squeegee, a screen cylinder device that rotatably supports the screen plate and holds the screen plate so as to be movable away from the impression cylinder; and the screen plate is attached to the impression cylinder via the screen cylinder device. In a rotary screen printing machine comprising: a screen cylinder attaching / detaching device that moves the screen squeezing and separating; and a squeegee attaching / detaching device that moves the squeegee in contact with and away from the inner peripheral surface of the screen plate. A first sheet on the basis of the phase detected by the detection means and the phase detection means; The screen cylinder attaching / detaching device and the squeegee attaching / detaching device are controlled so that the screen plate comes into contact with the impression cylinder and the squeegee comes into contact with the inner peripheral surface of the screen plate in synchronization with the timing of reaching the contact location of And a control device for controlling the squeegee attaching / detaching device so that the operation of attaching the squeegee to the inner peripheral surface of the screen plate is performed in a plurality of stages.

  The rotary screen printing machine according to the second invention for solving the above-mentioned problems is the first invention, wherein the control device is configured such that the operation of attaching the squeegee to the inner peripheral surface of the screen plate is performed as described above. A first stage operation in which a squeegee moves from a squeegee disengagement position separated from the screen plate to a squeegee stand-by position close to the screen plate, and the squeegee moves from the squeegee stand-by position to a squeegee wearing position in contact with the screen plate. The squeegee attachment / detachment device is performed separately from the second stage operation, and the movement speed of the squeegee in the second stage operation is lower than the movement speed of the squeegee in the first stage operation. It is characterized by controlling.

  According to a third aspect of the rotary screen printer for solving the above-mentioned problems, in the first or second aspect, the control device divides the operation of attaching the screen plate to the impression cylinder in a plurality of stages. The screen cylinder attaching / detaching device is controlled as described above.

  According to the rotary screen printing machine according to the present invention, it is possible to perform screen printing normally from the first sheet to be supplied, and to suppress the scattering of ink when the squeegee contacts the screen plate. Occurrence can be prevented.

It is explanatory drawing which shows the rotary screen printing machine which concerns on Example 1 of this invention. FIG. 2 is a plan development view showing a part of FIG. FIG. 3A is an explanatory diagram showing the relationship between the frame and the sub-frame, and FIG. 3B is an explanatory diagram showing the relationship between the frame, the sub-frame, and the screen cylinder attaching / detaching motor. It is a block diagram which shows the control structure of the rotary screen printing machine which concerns on Example 1 of this invention. FIGS. 5A and 5B are schematic views showing the positional relationship between the screen cylinder and the squeegee in Embodiment 1 of the present invention, FIG. 5A is the position before the phase (θ _n −180 °) of the impression cylinder, and FIG. position in the phase (θ _n -180 °) in FIG. 5 (c) shows the position in the subsequent phase theta _n of the impression cylinder. It is explanatory drawing which shows the example of a control of the screen cylinder and squeegee of the rotary screen printing machine which concerns on Example 1 of this invention in time series. It is explanatory drawing which shows the example of a control of the screen cylinder and squeegee of the rotary screen printer concerning Example 2 of this invention in time series. It is explanatory drawing which shows the example of a control of the screen cylinder and squeegee of the conventional rotary screen printer in time series.

  Hereinafter, a rotary screen printer according to the present invention will be described with reference to the drawings. The rotary screen printing machine according to the present invention is not limited to the following examples, and it goes without saying that various changes can be made without departing from the spirit of the present invention.

  Details of the rotary screen printing machine according to the first embodiment of the present invention will be described below with reference to FIGS.

  As shown in FIGS. 1 and 2, in the present embodiment, an impression cylinder 100 that holds and conveys a sheet (substrate) is rotatably supported between the left and right machine frames 101 and 101. A screen cylinder 201 is disposed opposite to the impression cylinder 100.

  A notch 100a is formed on the outer peripheral surface of the impression cylinder 100 at a position facing the shaft center, and the holding device configured to hold and release the sheet in the notch 100a. 102 is disposed. In this embodiment, it is assumed that the impression cylinder 100 has a cylinder diameter twice that of the screen cylinder 201.

  The screen cylinder 201 is fixed to the screen plate 201A in which a thin plate material obtained by etching a small hole corresponding to a pattern is formed into a cylindrical shape, and to both ends (left and right in FIG. 2) of the screen plate 201A to reinforce the screen plate 201A. And two end rings 201B and 201B. The screen body 201 is supported by the frames 101 and 101 via support members 202 and 202, screen brackets 203 and 203, and a subframe 204.

  Each of the support members 202 supports the end ring 201B in a detachable manner, and is rotatably supported by the screen bracket 203.

  Each of the screen brackets 203 includes a screen support portion 203a that rotatably supports the support member 202, and a rotary shaft support portion 203b that is disposed radially outside the screen cylinder 201 with respect to the screen support portion 203a. It is configured.

Both ends of a rotating shaft 205 extending parallel to the axial direction of the screen cylinder 201 are rotatably supported by the rotating shaft support portion 203b.
Gears 205 a are provided at both ends of the rotating shaft 205, and the gears 205 a mesh with a gear 202 a formed on the outer peripheral surface of the support member 202 via an intermediate gear 206. Further, the gear 205a on one end side (the right end side in FIG. 2) of the rotating shaft 205 meshes with the gear 207a of the screen cylinder drive motor 207 (see FIG. 1).

  Therefore, when the screen cylinder drive motor 207 is driven, the gear 207a of the screen cylinder drive motor 207, the gear 205a on one end side of the rotating shaft 205, the intermediate gear 206 on one side (right side in FIG. 2), and the support on one side (right side in FIG. 2). The driving force of the screen cylinder driving motor 207 is transmitted to one end side (right end side in FIG. 2) of the screen cylinder 201 via the gear 202a of the member 202 and one support member 202, and the gear 207a of the screen cylinder driving motor 207 is rotated. Gear 205a on one end side of shaft 205, rotation shaft 205, gear 205a on the other end side (left end side in FIG. 2), intermediate gear 206 on the other side (left side in FIG. 2), and other side (left side in FIG. 2) The other end side (the left end side in FIG. 2) of the screen cylinder 201 is also connected via the gear 202a of the support member 202 and the other support member 202. Driving force of the lean cylinder drive motor 207 is transmitted, both ends of the screen cylinder 201 is rotated by the screen cylinder drive motor 207.

  The sub frame 204 is disposed along the axial direction of the screen cylinder 201 and supports the rotating shaft support portion 203 b of the screen brackets 203 and 203.

  Further, as shown in FIG. 3A, the sub-frame 204 swings to the machine frame 101 via pins 208 fixed to the machine frame 101 by first connecting brackets 204a formed on both sides in the axial direction. It is supported freely.

Further, as shown in FIG. 3B, the second connecting bracket 204b formed on both axial sides of the subframe 204 has a screw shaft 209B connected to the motor shaft of the screen cylinder attaching / detaching motor 209A. It is swingably connected. More specifically, the screw shaft 209B is swingably connected to the second connecting bracket 204b via a pin 210 provided on a nut member 209C screwed to the screw shaft 209B. The nut member 209C advances and retreats in the axial direction of the screw shaft 209B by the feed screw mechanism when the screw shaft 209B rotates by the rotation of the screen cylinder attaching / detaching motor 209A.
The screen cylinder attaching / detaching motor 209A is provided to bring the screen cylinder 201 (more specifically, the screen plate 201A) into contact with or away from the impression cylinder 100, and the main body of the screen cylinder attaching / detaching motor 209A. Each part is fixed to the left and right machine frames 101 via a screen barrel attachment / detachment motor support member 211 so as to be swingable.

  Further, as shown in FIGS. 1 and 2, the ink 1 (see FIG. 5) inside the screen plate 201 </ b> A is supplied from the small hole of the screen plate 201 </ b> A to the impression cylinder 100 side in the screen cylinder 201 described above. A squeegee 221 including a blade (squeegee main body) 221A and a squeegee bar 221B as a support for supporting the blade 221A is held.

  Both ends of the squeegee 221 are swingably supported by the subframe 204 via squeegee support members 222 and 222 and support plates 223 and 223, respectively.

The squeegee support member 222 is a member that swingably supports the squeegee bar 221B.
The support plate 223 is a plate, and holds the squeegee support member 222 at one corner. A screw shaft 224B connected to the motor shaft of the squeegee attaching / detaching motor 224A is swingably connected to the other corner of the support plate 223, and the other corner is pivotally supported by the pin 226. A contact surface 223 a that contacts the pin 227 is provided. The screw shaft 224B is swingably connected to the support plate 223 via a pin 225 provided on a nut member 224C screwed to the screw shaft 224B. When the screw shaft 224B is rotated by the rotation of the squeegee attaching / detaching motor 224A, the nut member 224C advances and retreats in the axial direction of the screw shaft 224B by the feed screw mechanism.

The squeegee attaching / detaching motor 224A is provided to bring the squeegee 221 (more specifically, the blade 221A) into contact with or away from the inner peripheral surface of the screen plate 201A. A third connecting bracket 204c formed at both ends is supported through a pin 228 so as to be swingable.
Further, the pin 226 is fixed to a fourth connecting bracket 204d formed at both ends in the axial direction of the subframe 204, and the pin 227 is fixed to a fifth connecting bracket 204e formed at both ends in the axial direction of the subframe 204. Has been.

  Next, the control device of the rotary screen printing machine according to the present embodiment will be described. As shown in FIG. 4, the control device 300 of the rotary screen printing machine according to the present embodiment includes a signal output from the machine encoder 229 provided in the impression cylinder 100, a screen cylinder attachment / detachment provided in the screen cylinder drive motor 207. A signal output from the motor / encoder 230 and a signal output from the squeegee attaching / detaching motor / encoder 231 provided in the squeegee attaching / detaching motor 224A are input, and the screen cylinder driving motor 207, the screen cylinder attaching / detaching motor 209A, and the squeegee attaching / detaching motor 224A are input. Drive control is performed.

Hereinafter, control of the screen cylinder 201 and the squeegee 221 by the control device 300 according to the present embodiment will be described with reference to FIGS. 5 and 6. In FIG. 6, one rotation of the impression cylinder 100 (for example, θ _n−1 to θ _n and θ _n to θ _{n + 1} ) is shown as 360 °, and one rotation of the screen cylinder 201 is shown as 180 °. The same applies to FIGS.

First, as shown in FIG. 5A, before the printing operation is started, the screen cylinder 201 is positioned at the screen cylinder removal position separated from the impression cylinder 100, and the squeegee 221 has the tip of the blade 221A at the inner periphery of the screen plate 201A. The squeegee is positioned away from the surface. The screen cylinder at predetermined timing such screen cylinder 201 has ink 1 is prevailing on the inner peripheral surface of the screen plate 201A at the time of starting the printing of first sheet (point of theta _n shown in FIG. 6) It is assumed that the drive motor 207 rotates the drive.

When the printing operation is started in the rotary screen printing machine of the present embodiment, the control device 300 determines that the phase angle of the impression cylinder 100 is one based on the signal input from the machine encoder 229 as shown in FIG. Printing start phase of the first sheet (phase in which the notch portion 100a of the impression cylinder 100 faces the screen cylinder 201. In other words, the first sheet reaches the contact position between the impression cylinder 100 and the screen plate 201A. The phase of the screen cylinder 201 one rotation before the phase) θ _n (in this embodiment, the cylinder diameter of the impression cylinder 100 is twice the cylinder diameter of the screen cylinder 201. notch 100a and phase gap portion 100a of the opposite side of the axis is opposed to the screen cylinder 201. that is, when it becomes a theta _n -180 °), the impression cylinder 10 screen cylinder 201 The screen cylinder 201A is positioned close to the screen cylinder standby position, and the squeegee 221 is positioned at the squeegee standby position where the tip of the blade 221A is close to the inner peripheral surface of the screen plate 201A. The screw shaft 209B is rotated by the attachment / detachment motor 209A to move the nut member 209C, and the screw shaft 224B is rotated by the squeegee attachment / detachment motor 224A to move the nut member 224C. As shown in FIG. 5B, the squeegee standby position is a position where the tip of the blade 221A does not contact the ink 1 supplied into the screen plate 201A.

  As a result, the entire sub-frame 204 swings around the pin 208 in the direction in which the screen cylinder 201 approaches the impression cylinder 100 (counterclockwise in FIG. 1), and the support plate 223 moves the squeegee 221 around the pin 226. It swings in the direction of approaching the inner peripheral surface of the screen plate 201A (counterclockwise in FIG. 1).

  Based on signals input from the squeegee attaching / detaching motor / encoder 231 and the screen cylinder attaching / detaching motor / encoder 230, the control device 300 detects that the squeegee 221 is positioned at the squeegee standby position, as shown in FIG. Then, the squeegee attaching / detaching motor 224A is stopped. When it is detected that the screen cylinder 201 is positioned at the screen cylinder standby position, the screen cylinder attaching / detaching motor 209A is stopped. The operation in which the squeegee 221 is positioned from the squeegee disengaged position to the squeegee standby position is referred to as a first stage operation.

Thereafter, when the phase angle of the impression cylinder 100 reaches the printing start phase θ _n of the first sheet based on the signal input from the encoder 229, the control device 300 moves the screen cylinder 201 to the impression cylinder 100. The screen cylinder 201A is positioned at the screen wearing position where the screen plate 201A is brought into contact with the screen cylinder 201A. The screw shaft 209B is rotated by the motor 209A to move the nut member 209C, and the screw shaft 224B is rotated by the squeegee attaching / detaching motor 224A to move the nut member 224C.

  As a result, the entire sub-frame 204 swings around the pin 208 in a direction to bring the screen cylinder 201 close to the impression cylinder 100, and the support plate 223 moves the squeegee 221 around the pin 226 to the inner peripheral surface of the screen plate 201A. Swings in the direction of approaching.

  Based on the signals input from the screen cylinder attaching / detaching motor / encoder 230 and the squeegee attaching / detaching motor / encoder 231, the control device 300 confirms that the screen cylinder 201 is positioned at the screen wearing position as shown in FIG. If detected, the screen cylinder attaching / detaching motor 209A is stopped, and if it is detected that the squeegee 221 is positioned at the squeegee wearing position, the squeegee attaching / detaching motor 224A is stopped. The operation in which the squeegee 221 is positioned from the squeegee standby position to the squeegee wearing position is referred to as a second stage operation.

That is, the screen cylinder 201 and the squeegee 221 wait for approximately one rotation of the screen cylinder 201 in a state in which the screen cylinder 201 and the squeegee 221 are moved from the disengaged position to the standby position before reaching the print start phase θ _n of the first sheet, When the printing start phase θ _n of the first sheet is reached, each moves from the standby position to the arrival position, and at this timing, the first sheet reaches the contact point between the impression cylinder 100 and the screen plate 201A. Then, the ink 1 conveyed between the impression cylinder 100 and the screen plate 201A and extruded by the squeegee 221 from the through-hole formed in the plate surface of the screen plate 201A is transferred to the sheet.

  More specifically, the controller 300 avoids the blade 221A from coming into contact with the screen plate 201A when the screen plate 201A is not in contact with the impression cylinder 100. Simultaneously with the screen cylinder 201 and the squeegee 221 such that the tip of the blade 221A contacts the screen plate 201A immediately after the screen plate 201A contacts the impression cylinder 100. It is assumed that the moving speed, the moving time, and the like are controlled. The same applies to the following embodiments.

  As described above, in this embodiment, the controller 300 performs the operation of attaching the screen cylinder 201 to the impression cylinder 100 and the operation of attaching the squeegee 221 to the screen plate 201A step by step. According to the printing start phase, the screen plate 201A comes into contact with the impression cylinder 100 from a position closer to the impression cylinder 100 than before, and the tip of the blade 221A comes from the position closer to the inner peripheral surface of the screen plate 201A than before. Control is performed so as to contact the inner peripheral surface of the screen plate 201A.

  Thereafter, when printing of the last sheet is completed, the control device 300 rotates the screw shaft 209B by the squeegee attaching / detaching motor 224A to move the nut member 209C, and rotates the screw shaft 224B by the screen cylinder attaching / detaching motor 209A. The member 224C is moved. As a result, the support plate 223 swings around the pin 226 in the direction separating the squeegee 221 from the inner peripheral surface of the screen plate 201A (clockwise in FIG. 1), and the entire subframe 204 is screened around the pin 208. The cylinder 201 is swung in a direction in which the cylinder 201 is separated from the impression cylinder 100 (clockwise in FIG. 1).

  Based on the signals input from the screen cylinder attaching / detaching motor / encoder 230 and the squeegee attaching / detaching motor / encoder 231, the control device 300 determines that the screen cylinder 201 is positioned at the screen cylinder detaching position as shown in FIG. Is detected, the screen cylinder attaching / detaching motor 209A is stopped, and when it is detected that the squeegee 221 is positioned at the squeegee releasing position, the squeegee attaching / detaching motor 224A is stopped.

  In this embodiment, the support member 202, the screen bracket 203, and the subframe 204 constitute a screen cylinder apparatus, the screen cylinder attachment / detachment motor 209A constitutes a screen cylinder attachment / detachment apparatus, and the squeegee attachment / detachment motor 224A constitutes a squeegee attachment / detachment apparatus. This machine encoder 229 constitutes a phase detection means.

  According to the rotary screen printing machine according to the present embodiment described above, after the screen cylinder 201 is brought into contact with the impression cylinder 100 as in the prior art, the squeegee 221 is attached to the screen plate after waiting for the screen cylinder 201 to make one rotation. The screen cylinder 201 and the squeegee 221 are attached and detached with high accuracy by the screen cylinder attachment / detachment motor 209A and the squeegee attachment / detachment motor 224A, respectively. At the same time as or immediately after the screen cylinder 201 is brought into contact with the impression cylinder 100, the squeegee 221 is brought into contact with the inner peripheral surface of the screen plate 201A, so that screen printing is normally performed from the first sheet. It is possible to suppress occurrence of scraping paper.

  In addition, the wearing operation for moving the squeegee 221 from the squeegee removed position to the squeegee wearing position is divided into a plurality of stages, and the squeegee 221 is brought closer to the inner peripheral surface of the screen plate 201A stepwise before the first sheet is printed. As shown in FIG. 6, the squeegee 221 is brought into contact with the inner peripheral surface of the screen plate 201A from the squeegee standby position close to the inner peripheral surface of the screen plate 201A when the first sheet is printed. The moving speed of the squeegee 221 in the notch range a where the notch portion 100a of the impression cylinder 100 faces the screen cylinder 201 is lower than the conventional moving speed shown in FIG. 8, and the squeegee 221 is determined per unit time. , The squeegee 221 contacts the inner peripheral surface of the screen plate 201A. The impact load at the time is reduced, the scattering of the ink 1 when the squeegee 221 contacts the inner peripheral surface of the screen plate 201A can be suppressed, and the occurrence of printing defects can be prevented, and the load applied to the screen plate 201A can be reduced. This can reduce the life of the screen plate 201A.

In this embodiment, the screen cylinder 201 and the squeegee 221 are controlled to be positioned at the screen cylinder standby position and the squeegee standby position, respectively, when the phase angle of the impression cylinder 100 reaches θ _n −180 °. However, the timing of positioning the screen cylinder 201 and the squeegee 221 at the screen cylinder standby position and the squeegee standby position is not limited to the above-described embodiment, and may be performed at an appropriate timing.
In the present embodiment, the screen cylinder 201 and the squeegee 221 are once brought into a standby state in the state of being close to the impression cylinder 100 and the screen plate 201A, respectively, and then brought into contact with the impression cylinder 100 and the screen plate 201A, respectively. The screen cylinder 201 and the squeegee 221 may be divided into a plurality of times and brought close to the impression cylinder 100 and the screen plate 201A in stages, and then brought into contact with the impression cylinder 100 and the screen plate 201A, respectively.
In the present embodiment, an example is shown in which the squeegee 221 is supported via the support plate 223 that is swingably supported by the sub-frame 204 that supports the screen cylinder 201. The structure may be independently supported by the frame 101.
The same applies to the following embodiments.

The details of the rotary screen printing machine according to the second embodiment of the present invention will be described below with reference to FIGS. The rotary screen printing machine according to this embodiment is different from the rotary screen printing machine according to the first embodiment described above in the attachment / detachment operation of the screen cylinder 201 and the squeegee 221. The apparatus configuration is the same as that shown in FIGS. 1 to 4 and described in the first embodiment, and redundant description is omitted.
As shown in FIG. 7, in this embodiment, the control device 300 controls the squeegee attaching / detaching motor 224 </ b> A in the first embodiment shown in FIG. When positioning, control is performed so that the moving speed of the squeegee 221 gradually decreases.
In particular, when positioning the squeegee 221 in the wearing position, the squeegee attaching / detaching motor is required before the blade 221A contacts the inner peripheral surface of the screen plate 201A so that the tip of the blade 221A slowly contacts the inner peripheral surface of the screen plate 201A. Control is performed so that the rotational speed of 224A gradually decreases, in other words, gradually decreases. Alternatively, control is performed so that the moving speed of the squeegee 221 gradually decreases (decreases monotonically) as time elapses.

  As a result, the entire sub-frame 204 swings around the pin 208 in a direction to bring the screen cylinder 201 close to the impression cylinder 100, and the support plate 223 moves the squeegee 221 around the pin 226 to the inner peripheral surface of the screen plate 201A. It swings while reducing the moving speed in the direction to be close to.

As described above, in this embodiment, in addition to the controller 300 performing the operation of attaching the screen cylinder 201 to the impression cylinder 100 and the operation of attaching the squeegee 221 to the screen plate 201A in stages, the squeegee 221 is also performed. The screen plate 201A is controlled so that the moving speed gradually decreases to the screen plate 201A, and the screen plate 201A is closer to the impression cylinder 100 than the conventional one in accordance with the printing start phase of the first sheet. Control is performed so that the tip of the blade 221A comes into contact with the impression cylinder 100 and comes into contact with the inner peripheral surface of the screen plate 201A at a lower speed than the conventional one from a position closer to the inner peripheral surface of the screen plate 201A than the conventional one.
Other controls are substantially the same as those in the first embodiment described above, and detailed description thereof is omitted.

  In the present embodiment, the support member 202, the screen bracket 203, and the subframe 204 constitute a screen cylinder apparatus, the screen cylinder attachment / detachment motor 209A constitutes a screen cylinder attachment / detachment apparatus, and the squeegee attachment / detachment motor 224A constitutes a squeegee attachment / detachment apparatus. The machine encoder 229 constitutes phase detection means.

  According to the rotary screen printing machine according to the present embodiment described above, after the screen cylinder 201 is brought into contact with the impression cylinder 100 as in the prior art, the squeegee 221 is attached to the screen plate after waiting for the screen cylinder 201 to make one rotation. The screen cylinder 201 and the squeegee 221 are attached and detached with high accuracy by the screen cylinder attachment / detachment motor 209A and the squeegee attachment / detachment motor 224A, respectively. At the same time as or immediately after the screen cylinder 201 is brought into contact with the impression cylinder 100, it is possible to perform screen printing from the first sheet by bringing the squeegee 221 into contact with the inner peripheral surface of the screen plate 201A. Thus, occurrence of scraping paper can be suppressed.

  Also, before printing the first sheet, the squeegee 221 is brought close to the inner peripheral surface of the screen plate 201A in a stepwise manner, and close to the inner peripheral surface of the screen plate 201A when printing the first sheet. Since the squeegee 221 is brought into contact with the inner circumferential surface of the screen plate 201A from the standby position, the blade 221A is brought into contact with the inner circumferential surface of the screen plate 201A at a low speed. The impact load at the time of contact with the surface is reduced, the scattering of the ink 1 when the squeegee 221 contacts the inner peripheral surface of the screen plate 201A can be suppressed, and the occurrence of printing defects can be prevented. It is possible to extend the life of the screen plate 201A by reducing the load applied to the screen plate 201A.

  In this embodiment, the squeegee attaching / detaching motor 224A is used as the squeegee attaching / detaching device. However, for example, the basic movement is performed by a fluid (pneumatic or hydraulic) cylinder, and the squeegee 221 is close to the screen body 201. A stopper is provided to stop the movement of the squeegee 221 at the position, and after the movement of the squeegee 221 is stopped by the stopper, the stopper is operated at a slow speed by a speed reducer such as a damper, thereby moving the squeegee 221 from the close position to the squeegee wearing position. When moving, the tip of the blade 221A may slowly come into contact with the inner peripheral surface of the screen plate 201A.

  Further, the stopper is the pin 227 in FIG. 1, and the pin 227 is provided with an eccentric rotation shaft. After the squeegee 221 comes into contact with the pin 227 and stops at a close position, the rotation shaft of the pin 227 is rotated by a motor. Thus, when the squeegee 221 is controlled so that the moving speed gradually decreases, and the squeegee 221 is moved from the close position to the squeegee wearing position, the tip of the blade 221A is in contact with the inner peripheral surface of the screen plate 201A. You may make it contact slowly.

  The present invention is suitable for application to a rotary screen printer.

DESCRIPTION OF SYMBOLS 100 Impression cylinder 100a Notch part 101 Machine frame 102 Holding device 201 Screen cylinder 201A Screen plate 201B End ring 202 Support member 202a Gear of support member 203 Screen bracket 203a Screen support part 203b Rotating shaft support part 204 Subframe 204a First Connecting bracket 204b Second connecting bracket 204c Third connecting bracket 204d Fourth connecting bracket 204e Fifth connecting bracket 205 Rotating shaft 205a Rotating shaft gear 206 Intermediate gear 207 Screen cylinder drive motor 207a For driving Motor gear 208 pin 209A Screen cylinder attaching / detaching motor 209B Screw shaft 209C Nut member 210 pin 211 Screen cylinder attaching / detaching motor support member 221 Squeegee 21A Blade 221B Squeegee bar 222 Squeegee support member 223 Support plate 223a Abutting surface 224A Squeegee attaching / detaching motor 224B Screw shaft 224C Nut member 225, 226, 227, 228 Pin 229 Main unit encoder 230 Screen body attaching / detaching motor / encoder 231 Squeegee attaching / detaching motor / encoder 300 Control device

Claims (3)

An impression cylinder that holds and conveys the sheet;
A screen plate formed in a cylindrical shape;
A squeegee held inside the screen plate;
A screen cylinder device that rotatably supports the screen plate and holds the screen plate so as to be movable away from the impression cylinder;
A screen cylinder attachment / detachment device for moving the screen plate in contact with and away from the impression cylinder via the screen cylinder apparatus;
In a rotary screen printing machine comprising a squeegee attaching / detaching device for moving the squeegee in contact with and away from the inner peripheral surface of the screen plate,
Phase detection means for detecting the phase of the impression cylinder;
Based on the phase detected by the phase detection means, the screen plate comes into contact with the impression cylinder at the timing when the first sheet reaches the contact location between the impression cylinder and the screen plate. The screen body attaching / detaching device and the squeegee attaching / detaching device are controlled so as to be in contact with the inner peripheral surface of the screen plate, and the operation of attaching the squeegee to the inner peripheral surface of the screen plate is performed in a plurality of stages. And a control device for controlling the squeegee attaching / detaching device. In the control device, the operation of attaching the squeegee to the inner peripheral surface of the screen plate is a first stage operation in which the squeegee moves from a squeegee disengagement position separated from the screen plate to a squeegee standby position adjacent to the screen plate. And the second stage operation in which the squeegee moves from the squeegee standby position to the squeegee wearing position that contacts the screen plate, and compared with the movement speed of the squeegee in the first stage operation, The rotary screen printing machine according to claim 1, wherein the squeegee attaching / detaching device is controlled so that the moving speed of the squeegee in the second stage operation is low. 3. The rotary screen printing machine according to claim 1, wherein the control device controls the screen cylinder attaching / detaching device so that the operation of attaching the screen plate to the impression cylinder is performed in a plurality of stages.

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