JPH07304149A - Plate-making device of stencil printing device - Google Patents

Abstract

PURPOSE:To obtain an inexpensive stencil printing device which performs neither idle turn of a master nor a change of a size of an image, by a method wherein a frictional member is constituted so that the more it comes to the lowest part of a master supporting part, the greater frictional force between the frictional member and the outer circumferential surface of a master roll becomes gradually. CONSTITUTION:A master 1 is wound around a roll core is made of paper or synthetic resin in the direction of an arrow X and a master roll 1a is formed. The master 1 is supported by a master supporting device 10 so that the master 1 is drawn out in the direction opposite to a winding direction of the master 1. The quality of the material of the frictional member 6 is decided so that the more it comes to the lowest part of the master supporting device 10 from its upper part, the greater frictional force to be acted upon between the frictional member 6 and the outer circumferential surface of the master roll 1a becomes gradually. The frictional member 6 is formed of an elastic member such as urethane rubber or silicone rubber and a matter having rubber hardness within a range of 30 deg.-90 deg. is used for the frictional member 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stencil printing machine for punching a master for stencil printing wound in a roll shape.

[0002]

2. Description of the Related Art A digital heat-sensitive stencil printing apparatus is well known as a simple printing method. In the plate making apparatus of this stencil printer, a thermal head having a plurality of resistance heating elements arranged in a line in the main scanning direction is brought into contact with a master for heat-sensitive stencil, and the master is stepped by a pulse motor while energizing the resistance heating elements in a pulsed manner. The punched image was written in the master by moving it in the sub-scanning direction by the platen roller driven by. Next, the stencil printing apparatus automatically conveys the master in which the punched image is written in this way and automatically winds it around the outer peripheral surface of the cylindrical plate cylinder, and presses the master with a pressing means such as a press roller. Prints by continuously pressing the printing paper, causing the ink to seep out from the openings provided in the plate cylinder and the perforated parts of the master and transfer the ink to the printing paper.

As described in Japanese Utility Model Publication No. 3-10055, the above-mentioned master is made of a very thin thermoplastic resin film such as polyester, and synthetic fibers, Japanese paper, or a porous flexible support, or It has a laminated structure in which Washi paper and a mixture of synthetic fibers are laminated together,
A paper tube or a resin tube is used as a core material and wound in a roll shape. Such a roll-shaped master is rotatably supported by the holder of the plate making apparatus and is fed by the rotation of the platen roller.

[0004]

The above-mentioned stencil printing machine has a problem that the master resonates due to the vibration of the stepping motor to generate noise. In addition, the master is transported in the air, or the winding of the master loosens naturally,
There is a problem that the master meanders or the extension force of the master changes, the feed amount of the master by the platen roller changes, and the size of the image changes.

Therefore, in Japanese Utility Model Publication No. 4-20608, a side plate is provided on a core member, a braking spring piece is brought into sliding contact with the side plate, and a master fed from a roll-shaped master is pulled by a platen roller. , A method of applying an appropriate tension to the master has been introduced. In addition, JP-A-56-1
Japanese Patent No. 61767 discloses a method in which a brake mechanism is provided in a holder of a roll-shaped master and a back tension is directly applied to the master fed from the roll-shaped master.

However, in the system in which the braking spring pieces are slidably contacted with the side plate, the side plate has to be provided on the core member around which the master is wound, which increases the number of parts and the number of assembling steps, resulting in an increase in cost. There is a problem of becoming. Further, since a constant braking force is constantly applied to the side plates, a change in the braking force of 2 to 3 times occurs due to a change in the diameter of the roll-shaped master. Therefore, in this method, when the master is consumed and the diameter of the roll-shaped master is reduced, the braking force is increased, the load at the time of transporting the master by the platen roller is increased, and the transport amount of the master is reduced. There is a problem that the size of the changes.

In the method of applying back tension to the master, if the diameter of the roll-shaped master is large and the master has a certain weight, it is possible to apply an appropriate back tension to the master, but the master is consumed and roll-shaped. As the diameter of the master decreases and its weight decreases, the master rotates with a little force, and the above-mentioned problem occurs.

The present invention has been made in view of the above-mentioned problems, and an inexpensive stencil printing apparatus in which the roll-shaped master does not idle and the master can be reliably extended and the image size does not change. It is an object to provide a plate making device.

[0009]

The invention according to claim 1 is
Master supporting means for supporting a master roll obtained by winding a master for stencil printing in a roll shape, plate making means for heating and punching according to image information while pulling out the master from the master roll, and cutting means for cutting the master In the plate making apparatus of the stencil printing apparatus, the master supporting means is formed so as to hold the master roll by a substantially V-shaped contact surface that gradually expands upward, and the master support means is provided on the contact surface. The friction member has a shape or shape such that the friction force acting between the friction member and the outer peripheral surface of the master roll increases continuously or stepwise as it goes to the lowermost portion of the master support means. It is characterized in that the material is specified.

According to a second aspect of the present invention, the master support means changes the direction of the master in the opposite direction to the direction in which the master is wound and sends the master to correct the winding of the master wound in a roll shape. It is characterized in that it has a straightening correction portion at the end portion on the feeding side of the master.

[0011]

According to the first aspect of the present invention, as it goes toward the lowermost part of the contact surface of the substantially V-shaped master supporting means which gradually expands upward, it acts between the outer peripheral surface of the master roll. A roll-shaped master held by a master supporting means having a friction member whose shape or material is determined so that the frictional force increases continuously or stepwise is pulled out by a predetermined stretching force by the plate making means. It is perforated by heating according to the image information and cut by the cutting means.

According to the second aspect of the present invention, the master held by the master supporting means is sent by being turned in the direction opposite to the winding direction, and is corrected by the winding correction unit. .

[0013]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 20 is a plate making apparatus, reference numeral 30 is a plate cylinder, and reference numeral 40 is a plate discharge apparatus.

The plate making apparatus 20 supports the master roll 1a in which the master 1 for stencil printing is wound in a roll shape, and the master 1 is pulled out from the master roll 1a and heat-punched according to image information. Thermal head 3
And platen roller 2 mainly, plate making means, transport rollers 4a and 4b arranged downstream of the platen roller 2 for conveying the master 1, and arranged downstream of the conveyance rollers 4a and 4b to convey the master 1. Movable blade 5 that cuts to a specified length
Guillotine-type cutting means 21 including a and a fixed blade 5b
It is mainly composed of and.

Hereinafter, the master 1, the master supporting means 10, the platen roller 2, the thermal head 3, the conveying roller 4a,
4b, the configuration of the cutting means 21 will be sequentially described.

As shown in FIG. 1, the master 1 is wound around a roll core 1s made of paper or synthetic resin in the direction of arrow X,
The master roll 1a is formed. The master 1 is supported by the master supporting means 10 so as to be extended in a direction opposite to the winding direction of the master 1.

As shown in FIG. 2, the master supporting means 10 has substantially V-shaped abutting surfaces 11a and 11b which gradually expand upward, and affixes to the abutting surfaces 11a and 11b, respectively. It is mainly composed of the strip-shaped friction members 6, 6.
The master supporting means 10 includes the master roll 1a between the friction members 6 attached to the contact surfaces 11a and 11b.
Hold in.

The friction member 6 moves from the upper part of the master supporting means 10 to the lowermost part 10a thereof, and the master roll 1a
The material is determined so that the frictional force acting between the outer peripheral surface and the outer peripheral surface increases stepwise. The friction member 6 is formed of an elastic member such as urethane rubber or silicon rubber, and has a rubber hardness within the range of 30 ° to 90 °. In this embodiment, the friction member 6 having a high rubber hardness (90 °) is on the upper part of the master supporting means 10, and the low friction member (30 °) is the lowermost part 10a.
It is set so that the rubber hardness changes stepwise as affixed to. Further, as the friction member 6, members having different friction coefficients may be used in stages regardless of the difference in rubber hardness.

At the end of the master supporting means 10 on the paying-out side of the master 1, the roll-wound master 1 is bent in the direction opposite to the winding direction of the master 1 to correct the curl. Are integrally formed with the contact surface 11b.

The platen roller 2 has its shaft 2s rotatably supported by a side plate (not shown) of the stencil printing machine.
It is rotationally driven by a stepping motor (not shown) fixed to the same side plate.

The thermal head 3 is provided so as to extend in parallel with the shaft 2s of the platen roller 2, and can be brought into and out of contact with the platen roller 2 via the master 1 by a contacting / separating mechanism (not shown). . The thermal head 3 is a well-known type which selectively heats and melts and punches the master 1 based on a digital image signal which is processed and sent by an A / D conversion unit and a plate making control unit (both not shown) of a document reading unit (not shown). Has the function of.

Conveying rollers 4a and 4b are arranged downstream of the platen roller 2. Transport rollers 4a, 4b
Is a motor (not shown), which is rotationally driven at a speed slightly higher than the feeding speed of the platen roller 2 described above.

The movable blade 5a is located above the transport path of the master 1 near the downstream side of the transport rollers 4a and 4b, and above it.
Fixed blades 5b are provided below the blades 5b so as to extend parallel to the axis 2s of the platen roller 2.

The movable blade 5a is rotatably supported by a rack (not shown) on which the movable blade 5a is fixed, a side plate of the stencil printing apparatus, and a pinion that meshes with the rack, and a side plate of the stencil printing apparatus. A well-known lifting mechanism, which is provided and has a lifting motor connected to one end of the pinion via a rotation transmission member, can be lifted and lowered with respect to the fixed blade 5b.

A guide plate 9 for guiding the master 1 conveyed by the conveying rollers 4a and 4b toward the clamping means of the plate cylinder 30 which will be described later is provided on the downstream side of the conveying path of the cutting means 21.
Are arranged.

In FIG. 1, on the lower left side of the plate making apparatus 20, a porous cylindrical support cylinder 30a forming an inner peripheral surface thereof, and a metal or metal wound around the outer peripheral surface of the support cylindrical body 30a. A plate cylinder 30 having a two-layer structure with a resin mesh screen layer (not shown) is provided. The plate cylinder 30 is rotatably supported around a rotation center shaft 14 that also serves as an ink pipe 14, which will be described later. The plate cylinder 30 is driven to rotate clockwise and counterclockwise by a motor M (not shown).

On a part of the outer peripheral surface of the plate cylinder 30, a stage 15 made of a magnetic material is provided extending in parallel with the ink pipe 14, and the stage 15 is rotatably provided at one end thereof. Clamping means including a shaft 16s and a clamper 16 attached to the shaft 16s and having a rubber magnet that can be opened and closed with respect to the plane portion of the stage 15 is provided. The plate cylinder 30 is arranged so that the clamper 16 is stopped at a position substantially right above the plate, that is, a plate feeding position, and the clamper 16 is opened and closed by an opening / closing means (not shown).

Inside the plate cylinder 30, a side plate (not shown) is rotatably supported, and is rotated counterclockwise in synchronism with the plate cylinder 30 to come into contact with the inner peripheral surface of the plate cylinder 30 to transfer ink. The ink roller 13 to be supplied, the doctor roller 17 that is arranged in parallel with the ink roller 13 with a slight gap therebetween, and forms the ink reservoir 12 having a wedge-shaped cross section between the ink roller 13 and the ink roller 13, and the ink is supplied to the ink reservoir 12. Ink pipes 14 and 14 are arranged respectively. The ink roller 13, the doctor roller 17, and the ink pipe 14 form an ink supply device. A printing paper (not shown) is provided near the lower side of the outer peripheral surface of the plate cylinder 30 facing the ink roller 13.
A press roller 18 that is freely movable in contact with and separated from the plate cylinder 30 is arranged in synchronism with the sheet feeding.

In FIG. 1, below the plate making device 20,
A plate discharge device 40 is arranged. The plate discharging device 40 accommodates the plate discharging rollers 22 and 23 for separating and transferring the used master from the outer peripheral surface of the plate cylinder 30 and the separated master.
Plate ejection box 24 detachable from the stencil printing machine body
Consists of. The plate discharge roller 23 is moved toward and away from the outer peripheral surface of the plate cylinder 30 by an appropriate means.

Next, the operation of this stencil printing machine will be described. First, a document (not shown) is set in a document reading unit (not shown), a plate making start key is pressed, a start signal is sent from a controller (not shown), and a used master (not shown) is placed on the outer periphery of the plate cylinder 30. Peel off the surface.
At this time, the plate cylinder 30 is rotated in the clockwise direction and stopped at a position where the plate discharge roller 23 contacts the rear end of the used master,
At the same time, the plate discharge rollers 22 and 23 start to rotate in the directions of the arrows, respectively, and the plate discharge roller 23 is swung to the position shown by the phantom line in FIG. 1 and pressed against the used master rear end portion of the outer peripheral surface of the plate cylinder 30. To start peeling. At this time, the plate cylinder 30 resumes rotation in the clockwise direction. The used master separated from the outer peripheral surface of the plate cylinder 30 is discarded into the plate discharge box 24. After that, the plate cylinder 30 is stopped at a predetermined position, and the clamper 16 is opened by the opening / closing means of the clamper 16 (not shown) to enter the plate feed standby state.

By driving a stepping motor (not shown), the platen roller 2 starts to rotate and the master 1 is conveyed while being pulled out from the master roll 1a.

At this time, the diameter of the master roll 1a held by the master supporting means 10 becomes smaller as the master 1 is consumed, and the weight thereof becomes lighter, so that the position shown by the phantom line in FIG. , And further moves toward the lowermost portion 10a. In order to make the extension force of the master 1 by the platen roller 2 constant, the material of the friction member 6 is determined so that the frictional force acting between the platen roller 2 and the outer peripheral surface of the master roll 1a gradually increases. From the start of winding of 1a to the end of winding, it is pulled out with a substantially constant extension force.

Further, the master 1 wound in a roll is
When passing through the curl correction unit 7, the curl is bent in a direction opposite to the winding direction, the curl is corrected, and the curl is fed out.

The conveying force of the master 1 by the platen roller 2, the friction member 6 of the master supporting means 10 and the master roll 1a.
Although it varies depending on the magnitude of the frictional force acting between the master roll 1a and the outer peripheral surface of the master roll 1a, as described above, the master roll 1a has a substantially constant correction from the beginning to the end of the winding of the master roll 1a. Since it is pulled out by the extension force of, it becomes stable.

Further, the resistance heating element (not shown) of the thermal head 3 is selectively heated by the digital image signal processed and sent by the A / D converter and the plate making controller (both not shown), The master 1 is selectively heated and melted in accordance with image information and starts to be perforated.

Next, the master 1 moves to the platen roller 2,
The master 1 is transported by the rotation of the transport rollers 4a and 4b.
The tip of the clamper 16 has expanded in the standby state for plate feeding.
Sent to. When the number of steps of the stepping motor reaches a certain set value, it is determined that the front end of the master 1 that has been plate-formed has reached between the clamper 16 and the stage 15, and the clamper 16 is closed by an opening / closing means (not shown).

Simultaneously with this clamping operation, the plate cylinder 30 is rotated counterclockwise at the same peripheral speed as the conveying rollers 4a, 4b, and the master 1 is wound around the outer peripheral surface of the plate cylinder 30.

When the master 1 is wound on the outer peripheral surface of the plate cylinder 30 for a predetermined length, the plate cylinder 30, the conveying rollers 4a and 4b, and the platen roller 2 stop rotating. At the same time as this stop operation,
The movable blade 5a is lowered by an elevating mechanism (not shown), and the master 1 is cut between the fixed blade 5b and the master 1. And plate cylinder 3
0 is again rotated in the counterclockwise direction, the rear end (not shown) of the cut master 1 is extracted from the plate making device 20, and the master 1 that has already been made is completely wound around the outer peripheral surface of the plate cylinder 30. Taken.

After the master 1 that has been prepressed is wound around the outer peripheral surface of the plate cylinder 30, the plate cylinder 30 is rotated counterclockwise and the printing paper is fed, and the press roller 18 presses the plate cylinder 30. Is pressed to start printing and printing.

FIG. 3 shows another embodiment of the present invention. The friction member 8 shown in this embodiment differs from that shown in the above-described embodiments only in the shape. Friction member 8
The contact area with the outer peripheral surface of the master roll 1a is increased and the frictional force acting between the outer peripheral surface of the master roll 1a and the master roller 1a is continuously increased from the upper part of the master supporting means 10 toward the lowermost part 10a. It is formed like a triangle.

According to this embodiment, the master supporting means 10
The triangular friction member 8 is provided on the master supporting means 10 so that the frictional force acting between the outer peripheral surface of the master roll 1a and the outer peripheral surface of the master roll 1a continuously increases toward the lowermost part 10a of the master roll 1a. It is possible to reliably pull out the master roll 1a with a predetermined extension force from the beginning to the end of the winding to prevent the master roll 1a from idling.

Modifications of the friction member 8 shown in FIG. 3 are shown in FIGS. The friction member 28 shown in this modified example is inserted into the triangular holes 29 formed in the contact surfaces 11a and 11b of the master supporting means 10, respectively, and the contact surfaces 11a and 11b.
It is supported so as to be flush with. Friction member 28
As a high friction member, for example, its rubber hardness is 30 ° to
50 ° urethane rubber is used, while the contact surface 11
Low friction members such as urethane rubber having a rubber hardness of 60 ° to 90 ° are used as a and 11b. Alternatively, both may be formed by combining urethane rubber and silicon rubber.

[0043]

As described above, according to the invention described in claim 1, the master roll of the master roll is moved toward the lowermost part of the contact surface of the substantially V-shaped master supporting means which is gradually expanded upward. The frictional force acting between the outer peripheral surface is continuous or
The master support means is provided with a friction member whose shape or material is determined so as to gradually increase, so that the master roll can be reliably pulled out by the plate-making means with a predetermined extension force, and the master roll can rotate freely. It is possible to provide an inexpensive plate making apparatus for a stencil printing apparatus in which the image size does not change.

According to the second aspect of the invention, since the curl correction portion is provided at the end of the master of the master support means on the feeding side of the master, the curl of the roll-shaped master can be corrected. Further, since the master is pulled out from the master roll by the plate making means with a predetermined stretching force, it is possible to perform a stable curl correction from the beginning to the end of the winding of the master roll.

[Brief description of drawings]

FIG. 1 is a side view of a plate making apparatus of a stencil printing apparatus showing an embodiment of the present invention.

FIG. 2 is a perspective view showing a master supporting means of the plate making apparatus shown in FIG.

FIG. 3 is a perspective view showing another embodiment of the present invention.

FIG. 4 is a perspective view showing a modified example of the friction member shown in FIG.

5 is an enlarged cross-sectional view of VV of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 master 1a master roll 2 platen roller 3 thermal head 4a, 4b conveyance rollers 6, 8, 28 friction member 10 master support means 11a, 11b contact surface 20 plate making device 21 cutting means 30 plate cylinder 40 plate discharge device

Claims (2)

[Claims] 1. A master supporting means for supporting a master roll in which a master for stencil printing is wound in a roll shape, a plate making means for heating and punching the master according to image information while pulling out the master from the master roll, and the master. In the plate making apparatus of the stencil printing apparatus, the master supporting means is formed to hold the master roll by a substantially V-shaped contact surface that gradually widens upward. A friction member is provided on the contact surface, and the friction member continuously or gradually increases the frictional force acting on the outer peripheral surface of the master roll as it goes to the lowermost part of the master support means. A plate making apparatus of a stencil printing apparatus, characterized in that the shape or the material is determined so that 2. The master supporting means changes the direction of the master in the opposite direction to the winding direction and sends out the master.
2. The plate making apparatus for a stencil printing apparatus according to claim 1, further comprising a curl correction unit for correcting the curl of the master wound in a roll shape, at the end of the master on the feeding side.