JPH082083A - Plate cylinder for screen printing - Google Patents

Abstract

PURPOSE:To provide a plate cylinder improved so as not only to effectively reduce the collision sound of a press roller but also to generate no large noise even at the time of high speed printing by the addition of simple constitution. CONSTITUTION:In the plate cylinder for screen printing having screen printing stencil paper wound around its outer peripheral surface and receiving the pressing force of a press roller on its outer peripheral surface in a printing operation angle-of-rotation region, a shock absorbing member 17 is provided to a region where the press roller 3 lands on the outer peripheral surface of the plate cylinder to collide with it on the start end side of the printing operation angle-of- rotation region. Since the press roller 3 lands on the shock absorbing member 17 on its outer peripheral surface of the plate cylinder 1 to collide with it, its collision energy is absorbed by the buffering action of the shock absorbing member 17 and the shock acting on the plate cylinder 1 is reduced. By this constitution, a collision sound is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stencil printing plate cylinder, and more particularly to a stencil printing plate cylinder used in a stencil printing apparatus for performing stencil printing in a pressing manner by a press roller.

[0002]

2. Description of the Related Art A stencil printing machine for performing stencil printing by pressing with a press roller has a cylindrical plate cylinder having an ink permeable structure in which a stencil sheet is wound around an outer peripheral surface and is supplied with printing ink from the inside. In the printing operation rotation angle region, the press roller is pressed against the outer peripheral surface of the plate cylinder in the feeding state, and the print paper is sandwiched between the stencil base paper and the press roller on the outer peripheral surface of the plate cylinder, so that the print paper is pressed against the stencil base paper. Then, stencil printing is performed by pressing.

In this stencil printing machine, since the base paper clamp mechanism for clamping the front end of the stencil base paper is provided on the outer peripheral surface of the plate cylinder, the press roller is arranged as a base paper clamp mechanism in the area where the base paper clamp mechanism is arranged. Is separated from the outer peripheral surface of the plate cylinder in order to avoid the interference, and is pressed against the outer peripheral surface of the plate cylinder only in the printing operation rotation angle region while avoiding this region. As specific examples of the retracting drive of the press roller, there are known ones that are performed by cams that are integrally provided at both ends of the plate cylinder and one that is performed by using an actuator such as a solenoid device.

[0004]

In any case, since the press roller always makes a landing collision with the outer peripheral surface of the plate cylinder at the start end side of the printing operation rotation angle region once for each rotation of the plate cylinder,
A collision noise is generated during this landing collision. This collision sound becomes louder during high-speed printing when the plate cylinder is rotated at a higher speed, and becomes an unpleasant noise that does not suit the office environment.

Further, when the press roller makes a landing collision with the outer peripheral surface of the plate cylinder, the plate cylinder is repeatedly fatigued by the impact acting on the plate cylinder, which causes the life of the plate cylinder to be shortened.

The present invention has been made by paying attention to the problems as described above. By adding a simple structure, the collision noise of the press roller can be effectively reduced, and a large noise is generated even at the time of high speed printing. It is an object of the present invention to provide a stencil printing cylinder that has been improved so as not to interfere with durability.

[0007]

In order to achieve the above-mentioned object, a stencil printing cylinder according to the present invention has a stencil sheet wrapped around an outer peripheral surface thereof, and a press roller is mounted on the outer peripheral surface in a printing operation rotation angle region. In the stencil plate cylinder to be pressed against, a shock absorbing member is provided at a position where the press roller makes a landing collision with the outer peripheral surface of the plate cylinder at the start end side of the printing operation rotation angle region.

[0008]

According to the above-mentioned structure, since the press roller makes a landing collision with the shock absorbing member on the outer peripheral surface of the plate cylinder, the collision energy is absorbed by the shock absorbing function of the shock absorbing member, and the shock acting on the plate cylinder is not affected. Reduce. This reduces the collision noise.

When the shock absorbing member projects from the outer peripheral surface of the plate cylinder with a predetermined thickness, the step surface on the printing operation rotation angle region side of the shock absorbing member smoothes the outer peripheral surface of the plate cylinder and the upper surface of the shock absorbing member. Since it is the inclined surface connected to the plate cylinder, no gap is generated between the stencil sheet M mounted on the plate cylinder outer peripheral surface and the plate cylinder outer peripheral surface.

[0010]

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

1A to 1C show an embodiment of a stencil printing machine including a stencil printing cylinder according to the present invention.
In these drawings, reference numeral 1 is a stencil printing cylinder (hereinafter,
Reference numeral 3 indicates a press roller, respectively.

The plate cylinder 1 is composed of a cylindrical body having an ink permeation structure, has a base paper clamp mechanism 5 on the outer peripheral surface thereof, and is mounted by winding a stencil base paper (not shown) whose front end is clamped by the base paper clamp mechanism 5. It is rotationally driven in the counterclockwise direction in the figure by a plate cylinder drive mechanism (not shown).

The base paper clamp mechanism 5 is rotatable about 180 degrees between the clamp base member 7 fixedly mounted on the outer peripheral surface of the plate cylinder 1 and the plate cylinder 1 between a clamp position and an unclamp position by a pivot shaft 9. The clamp plate 11 is provided.

The plate cylinder 1 has an ink permeable structure except for the arrangement portion of the base paper clamp mechanism 5, and the printing ink is metered and supplied to the inner peripheral surface by an ink supply mechanism (not shown) arranged in the cylinder. It If a more detailed description of the structure of the plate cylinder 1 is required, Japanese Patent Laid-Open No. 165295/1985 is recommended.
See JP-A-61-228982.

The ink permeation structure region is a stencil printable rotation angle region. Here, as shown in FIG. 1 (a), the stencil printable region is a region indicated by reference numeral A, and the base paper clamp is used. The non-printing rotation angle region, which is another rotation angle region including the arrangement region of the mechanism 5, is a region indicated by reference numeral B.

Plate cams 13 are fixedly attached to both ends of the plate cylinder 1, respectively. The plate cam 13 forms a small diameter cam surface 13a in a rotation angle area corresponding to the printing operation rotation angle area A, and a large diameter cam surface 1a in a rotation angle area corresponding to the non-printing rotation angle area B.
A cam follower 15 which is formed in cooperation with the press roller 3 is in contact with these cam surfaces by a spring force of a spring device (not shown).

With this cam mechanism, the press roller 3 is
In the printing operation rotation angle region A of the plate cylinder 1, as shown in FIG.
As shown in FIG. 1, in the non-printing rotation angle region B of the plate cylinder 1 which is pressed against the outer peripheral surface of the plate cylinder 1,
As shown in (b), it is separated from the outer peripheral surface of the plate cylinder 1 to avoid interference with the base paper clamp mechanism 5.

A shock absorbing member 17 is attached to the outer peripheral surface of the plate cylinder 1 at the start end side of the printing operation rotation angle region A and at a position where the press roller 3 makes a landing collision with the outer peripheral surface of the plate cylinder.

The shock absorbing member 17 may be in the form of a strip and extend over the entire area of the outer peripheral surface of the plate cylinder in the axial direction, or may be partially provided in the outer peripheral surface of the plate cylinder. .

Suitable materials for the shock absorbing member 17 include rubber-like elastic members, foams, felts, and non-woven fabric laminates, which have appropriate elasticity and printing ink resistance for shock absorption. All you have to do is prepare.

Suitable rubber-like elastic members for the shock absorbing member 17 include isoprene rubber, butadiene rubber, chloroprene rubber, butyl rubber, acrylic rubber, silicone rubber, fluororubber, urethane rubber, nitrile isoprene rubber, polysulfide rubber, epichlorohydrin rubber. Among them, silicone rubber, fluororubber, chloroprene rubber, and urethane rubber are more preferable than the printing ink resistance.

FIG. 1A shows a printing operation rotation phase state in which the plate cylinder 1 corresponds to the press roller 3 in the printing operation rotation angle area A. Under this state, the cam follower 15 has a small diameter of the plate cam 13. The press roller 3 is pressed against the outer peripheral surface of the plate cylinder 1 by corresponding to the cam surface 13a,
The printing paper P fed between the plate cylinder 1 and the plate cylinder 1 is pressed against a stencil sheet (not shown) wound around the outer peripheral surface of the plate cylinder 1 with a predetermined press pressure. As a result, stencil printing is carried out by pressing with a predetermined press pressure.

When the rotation of the plate cylinder 1 progresses from the above state and the plate cylinder 1 reaches the printing operation rotation phase corresponding to the press roller 3 in the non-printing rotation angle region B, it is shown in FIG. 1 (b). As described above, the cam follower 15 is the small-diameter cam surface 1 of the plate cam 13.
3a, and the large diameter cam surface 13b is lifted away from the corresponding relationship, and the press roller 3 is moved away from the outer peripheral surface of the plate cylinder 3 so as to avoid interference with the base paper clamp mechanism 5 by this lift.

From this, the rotation of the plate cylinder 1 progresses further, and as shown in FIG.
As shown in (c), when the plate cylinder 1 shifts to the printing operation rotation phase state corresponding to the press roller 3 in the printing operation rotation angle area A, the cam follower 15 causes the large diameter cam surface 13 b of the plate cam 11. Away from the engagement with the cam surface toward the small-diameter cam surface 13a, and the press roller 3
But approach the outer peripheral surface of the plate cylinder 1 and land on the outer peripheral surface of the plate cylinder 1.

Since the impact absorbing member 17 is provided at a portion where the press roller 3 lands and collides with the outer peripheral surface of the plate cylinder 1, the press roller 3 lands and impacts the impact absorbing member 17.

As a result, the shock generated when the press roller 3 makes a landing collision with the outer peripheral surface of the plate cylinder 1 is buffered and absorbed by the shock absorbing member 17, and a large collision noise is avoided at the time of this landing collision.

The shock absorbing member 17 may be made of a rubber-like adhesive material. In this case, the plate cylinder 1
The stencil sheet to be wound around the outer peripheral surface of the sheet is releasably attached to the shock absorbing member 17, and the deviation of the stencil sheet during printing is suppressed. Further, it is possible to prevent the stencil sheet from being flipped up after the clamp is released when the stencil sheet is removed from the plate cylinder 1 and discharged.

As shown in FIG. 2, when the shock absorbing member 17 is attached to the outer peripheral surface of the plate cylinder 1 in a sticking manner, a step is formed on the outer peripheral surface of the plate cylinder by the thickness of the shock absorbing member 17. Occurs,
On the side of the printing operation rotation angle region A, a gap S is formed between the stencil sheet M wound and mounted so as to cover it and the outer peripheral surface of the plate cylinder. The printing ink collects in the gap S, and the printing ink leaks to the outside from both sides of the gap S opened, so that the impact absorbing member 17 performs the printing operation as shown in FIG. It is preferable that the side of the rotation angle region A has an inclined surface 17a in order to avoid the occurrence of the gap S.

Further, as shown in FIG. 4, the shock absorbing member 17 may be fitted and mounted in a mounting recess 19 formed in the plate cylinder 1. In this case, a large step does not occur on the outer peripheral surface of the plate cylinder, and the above-described gap S does not occur.

Further, as shown in FIG. 5, the outer peripheral surface of the press roller 3 may be composed of a relatively thin buffer layer 21.

[0031]

As can be understood from the above description, according to the stencil printing plate cylinder of the present invention, the collision of the press rollers can be achieved only by adding a simple structure in which an impact absorbing member is arranged on the outer peripheral surface of the plate cylinder. Sound is effectively reduced, large noise is avoided even during high-speed printing, quietness during printing operation is improved, and the office environment is not deteriorated by unpleasant noise when used in general offices. .

Further, due to the shock absorbing function of the shock absorbing member,
Since the impact of the press roller on the plate cylinder at the time of landing collision is reduced, the life of the plate cylinder can be extended.

When the shock absorbing member projects from the outer peripheral surface of the plate cylinder with a predetermined thickness, the step surface on the printing operation rotation angle region side of the shock absorbing member smoothes the outer peripheral surface of the plate cylinder and the upper surface of the shock absorbing member. Since the inclined surface is connected to the plate cylinder, there is no gap between the stencil sheet M attached to the outer surface of the plate cylinder and the outer surface of the plate cylinder. Occurrence is avoided.

[Brief description of drawings]

1A to 1C are schematic configuration diagrams showing an embodiment of a stencil printing apparatus including a stencil printing cylinder according to the present invention.

FIG. 2 is an enlarged side view showing an essential part of a stencil printing cylinder according to the present invention.

FIG. 3 is a side view showing an enlarged main part of an improved embodiment of the stencil printing cylinder according to the present invention.

FIG. 4 is a side view showing an enlarged main part of another embodiment of the stencil printing cylinder according to the present invention.

FIG. 5 is a side view showing an enlarged main part of another embodiment of the stencil printing cylinder according to the present invention.

[Explanation of symbols]

 1 Stencil plate for stencil printing 3 Press roller 5 Base paper clamping mechanism 13 Plate cam 15 Cam follower 17 Impact absorbing member

Claims (2)

[Claims] 1. A stencil sheet is wound around and attached to an outer peripheral surface,
In a stencil printing cylinder in which a press roller is pressed against the outer peripheral surface in the printing operation rotation angle region, shock absorption is performed at a portion where the press roller makes a landing collision with the outer peripheral surface of the plate cylinder at the start end side of the printing operation rotation angle region. A stencil printing cylinder comprising a member. 2. The impact absorbing member projects from the outer peripheral surface of the plate cylinder with a predetermined thickness, and the step surface on the printing operation rotation angle region side of the impact absorbing member smoothes the outer peripheral surface of the plate cylinder and the upper surface of the impact absorbing member. The plate cylinder for stencil printing according to claim 1, wherein the plate cylinder is an inclined surface connected to the.