JPH0789206A - Screen printing machine - Google Patents

Abstract

PURPOSE:To provide a screen printing machine in which the evaporation or drying of ink or the contamination within the machine and the plate cylinder thereof due to flow of ink are prevented even when soft ink good in fluidity is used. CONSTITUTION:A screen printing machine is equipped with a rotatable porous plate cylinder 1, the ink roller 8 rotatably supported within the plate cylinder 1 by side plates 6, 7, the doctor roller arranged in close vicinity to the outer peripheral surface of the ink roller 8 and rotatably supported a by the side plates 6, 7 and an ink supply means 10 for supplying ink to the ink sump 11 of the wedge-shaped space formed by the outer peripheral surfaces of both of the ink roller 8 and the doctor roller 9 and further equipped with the shield plate 12 operably supported by the side plates 6, 7 and hermetically closing the ink sump 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plate cylinder in a stencil printing machine.

[0002]

2. Description of the Related Art A porous support cylinder and a mesh screen layer which is a mesh of resin or metal fiber, and a thermoplastic resin film (hereinafter referred to as "film") are provided on the outer peripheral surface of the mesh screen layer. A cylindrical plate cylinder, which is composed of an ink-permeable support, around which a stencil printing master (hereinafter referred to as "master") that has been perforated by a plate-making means is wound, and an inner peripheral surface of the plate cylinder. It has an ink supply member that comes into contact with and supplies ink to the master wound on the outer peripheral surface of the plate cylinder, and presses the outer peripheral surface of the plate cylinder with a pressing member such as a press roller through the printing paper. Thus, stencil printing is widely known, in which ink is exuded from the plate cylinder opening and the master perforation and transferred to printing paper to perform printing.

Generally, in the stencil printing, a relatively hard emulsion type (water-in-oil type) ink is used, and the ink transferred to the printing paper at the time of printing permeates into the printing paper and the finger or the like. No dirt will occur when rubbed with
It took a certain amount of time (several tens of seconds) to reach the so-called set state. Then, when the next printing paper is stacked before the setting is completed, the so-called show-through occurs, in which the ink of the image portion of the previous printing paper is transferred to the back surface of the next printing paper. There was a problem that it would end up.

Therefore, in order to shorten the time required for the ink to reach the set state, gradually soft ink has come to be used.

[0005]

In the conventional stencil printing machine, as disclosed in Japanese Patent Laid-Open No. 63-265679, the plate cylinder is detachably attached to the main body of the stencil printing machine. When using the above-mentioned soft ink in such a stencil printing machine, when the printing paper is jammed in the printing machine, when the plate cylinder is removed from the stencil printing machine body and the processing is performed, There is a problem that the ink drops from the ink reservoir or scatters to stain the inside of the plate cylinder and the inside of the apparatus. Also, in the case where a plurality of plate cylinders of each color are prepared and printing is carried out by detaching and exchanging them for printing, as in the case of multicolor printing, the ink is scattered and the inside of the plate cylinder and the inside of the apparatus are contaminated in the same manner as described above. There is a problem. Further, since the plate cylinder is detachable, the plate cylinder removed from the printing device is not always stored in a horizontal state, and when it is stored at an angle, the ink flows to the lower side due to its own weight,
There is a problem that the inside of the plate cylinder gets dirty.

The present invention provides a stencil printing machine which prevents the inside of the plate cylinder and the inside of the device from being contaminated without the ink flowing out when the plate cylinder is replaced or stored even when a soft ink is used. It is provided.

[0007]

The invention according to claim 1 is
A porous cylinder, a rotatable plate cylinder, and an ink roller arranged to abut the outer peripheral surface on the inner peripheral surface of the plate cylinder and rotatably supported on a side plate in the plate cylinder, A doctor roller that is supported by the side plate and that is arranged with the outer peripheral surface of the ink roller close to the outer peripheral surface of the ink roller, a wedge shape formed by the outer peripheral surface of the ink roller and the outer peripheral surface of the doctor roller. In a stencil printing machine having an ink supply means for supplying ink to an ink reservoir in a space, a stencil printing plate supported by the side plate and capable of opening and closing to seal the ink reservoir is provided.

According to a second aspect of the present invention, a porous cylindrical cylinder is provided which is rotatable and is arranged so that the outer peripheral surface of the plate cylinder abuts on the inner peripheral surface of the plate cylinder. An ink roller rotatably supported by the side plate, a doctor roller supported by the side plate, the outer peripheral surface of the doctor roller being arranged close to the outer peripheral surface of the ink roller, and the outer peripheral surface of the ink roller, In a stencil printing machine comprising an ink supply means for supplying ink to an ink reservoir in a wedge-shaped space formed with the outer peripheral surface of a doctor roller, the ink roller outer peripheral surface and the ink roller outer peripheral surface are supported in the wedge-shaped space. Selectively moveable to a first position in contact with the outer peripheral surface of the doctor roller and a second position separated from the outer peripheral surface of the ink roller and the outer peripheral surface of the doctor roller. And a porous member that absorbs ink in the ink reservoir when it occupies the first position and the side plate, and the porous member moves from the first position to the second position. In this case, the diaphragm member is provided at a position where the porous member is brought into pressure contact with the porous member.

[0009]

According to the first aspect of the invention, the openable and closable shield plate seals the ink reservoir.

According to the second aspect of the invention, when the porous member occupies the first position where it contacts the outer peripheral surface of the ink roller and the outer peripheral surface of the doctor roller respectively, the ink in the ink reservoir is absorbed.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1 showing the first embodiment of the present invention,
Cylindrical plate cylinder 1 with a porous structure having a large number of holes on its outer peripheral surface
Is rotatably supported by a frame of a printing device (not shown),
The ink supply pipe 2 that also serves as the rotation axis of the plate cylinder 1 is fixed to the frame body. On the outer peripheral surface of the plate cylinder 1, there are provided a clamper 3 rotatable about an axis 3a and a stage section 4 which is a flat surface portion along one generatrix of the plate cylinder 1. Has a magnet not shown attached,
Holds the tip of the plate-made master 5.

Inside the plate cylinder 1, a pair of side plates 6 and 7 fixed to the ink supply pipe 2 are arranged, and an ink roller 8 is rotatably supported on the side plates 6 and 7. There is. The ink roller 8 is arranged so that its outer peripheral surface abuts on the inner peripheral surface of the plate cylinder 1, and is rotationally driven in the arrow direction shown in FIG. A doctor roller 9 is provided in the vicinity of the ink roller 8, and the doctor roller 9 is arranged so as to have an extremely small gap between the outer peripheral surface thereof and the outer peripheral surface of the ink roller 8. A supply nozzle 10 as an ink supply means is attached to the ink supply pipe 2, and the ink passes from the ink supply pipe 2 through the supply nozzle 10 to the outer peripheral surface of the ink roller 8 and the doctor roller 9.
It is supplied to the ink reservoir 11 in a wedge-shaped space formed in the vicinity of the outer peripheral surface of the. The doctor roller 9 may be a non-rotating body, or may be configured to rotate in the direction opposite to the ink roller 8 toward the ink reservoir 11 so as to return the ink adhering to the outer surface thereof to the ink reservoir 11. Good.

A shield plate 12 is provided above the ink reservoir 11.
Is provided. The shielding plate 12 is a plate having a length substantially the same as the lengths of the ink roller 8 and the doctor roller 9, and as shown in FIG. 2, at the end portion on the side opposite to the base portion 12a, the protrusion 12b facing downward. Are formed. At the lower part of the base portion 12a, there is a protrusion 12c protruding downward.
Are formed along the base portion 12a. The base 12a includes an operating piece 12d directed upward in a direction orthogonal to the shield plate 12.
Are erected integrally. Each ridge 12b, 12c is
The gap between the two is larger than the width of the ink reservoir 11. The shield plate 12 is rotatably supported between the side plates 6 and 7 by shafts 13 at both ends of the base portion 12a, and both side ends thereof are in sliding contact with the side plates 6 and 7.

A solenoid 14 is provided on the upper left side of the shield plate 12.
Is provided. The solenoid 14 has a bearing portion 14b at the end opposite to the plunger 14a, and in this bearing portion 14b, a pin 15 planted in the side plate 6 is provided.
It is swingably supported by. A free end portion of the actuating piece 12d is swingably locked by a locking pin 16 at the tip of the plunger 14a. The operating piece 12d is the plunger 14.
A compression spring 17 is provided between the portion locked to a and the solenoid 14 main body.
Urges the normal and actuating pieces 12d in the direction of pushing out (rightward in FIG. 1).

The operation of the present invention will be described based on the above configuration. When the plate cylinder 1 is mounted on the main body of the stencil printing machine and the solenoid 14 is electrically connected by connecting a connector or the like, the plunger 14a is attracted and the shield plate 12 is attached to the shaft 13
It rotates in the counterclockwise direction about and moves to the position shown by the solid line in FIG. At this time, the protrusions 12b and 12c are respectively attached to the outer peripheral surface of the ink roller 8 and the doctor roller 9.
Is separated from the outer peripheral surface of.

Printing is then performed, but if a trouble such as a paper feed jam or a paper discharge jam occurs during printing, a control device (not shown) displays an alarm on the operation panel of the stencil printing machine and the solenoid 14 is turned on. Turn off the power.
Then, the plunger 14a is urged by the compression spring 17 and pulled out, and the shield plate 12 rotates clockwise and moves to the position shown by the chain double-dashed line in FIG. And each ridge 12
b and 12c come into contact with the outer peripheral surface of the ink roller 8 and the outer peripheral surface of the doctor roller 9, respectively, and the ink reservoir 1
Seal 1 Also, when the plate cylinder 1 is removed from the stencil printing machine main body during printing, when the solenoid 14 is electrically disconnected, the plunger 14a is pulled out in the same manner as described above, and the shield plate 12 is rotated clockwise. , Each ridge 12
b and 12c seal the ink reservoir 11.

As a modification of the first embodiment, the shield plate 12 shown in FIG. 3 may be used instead of the shield plate 12. The shield plate 18 is composed of a base portion 18a and a shield portion 18b. Similar to the base 12a, the base 18a is rotatably supported by the shaft 13 between the side plates 6 and 7.
An operation piece (not shown) is vertically provided integrally on the 8a. The free end of this operating piece is the plunger 14a.
Is rotatably engaged with the tip of the. Also, the base portion 18a
One or a plurality of support arms 18c extending in the horizontal direction are integrally provided in the. The shielding portion 18b is a plate curved so that its central portion projects upward, and its length is substantially the same as the generatrix length of the ink roller 8 and the doctor roller 9. On the upper surface of the central portion of the shielding portion 18b, the connecting portion 18 is provided at a position corresponding to the supporting arm 18c.
One or more d are provided. The base portion 18a and the shield portion 18b are engaged with each other at the support arm 18c and the connection portion 18d, and the shield portion 18b is swingably supported by the base portion 18a. When the shielding plate 18 configured as described above is used, both end portions 18e and 18f of the shielding portion 18b surely contact the outer peripheral surface of the ink roller 8 and the outer peripheral surface of the doctor roller 9, respectively, and the above-described first embodiment is different. Similarly, the ink reservoir 11 can be reliably sealed. The shield plate 12 and the shield part 18b of the shield plate 18 are preferably formed of an elastic body such as rubber. With this structure, the protrusions 12b and 12c or both ends 18e and 18f are formed.
Reliably contacts the outer peripheral surface of the ink roller 8 and the outer peripheral surface of the doctor roller 9, and can reliably seal the ink reservoir 11.

Further, as a modification of the first embodiment, instead of the shield plate 12, a shield plate 19 shown in FIG. 4 may be used. The shield plate 19 is formed of an elastic body such as rubber, and is integrally composed of a base portion 19a and a shield portion 19b. An operating piece (not shown) is vertically erected integrally with the base portion 19a, and a free end portion of the operating piece is rotatably engaged with a tip portion of the plunger 14a. Base 1
Similarly to the base portion 12a, the shaft 9a is rotatably supported by the shaft 13 between the side plates 6 and 7. The plate-shaped shield portion 19b extending from the base portion 19a to the ink roller side is folded back inward from a substantially central portion thereof. When this shield plate 19 is used, the bent portion 19c and the free end portion 19d of the shield plate 19 are respectively caused by the elastic deformation of the shield portion 19b.
The outer peripheral surface of the doctor roller 9 and the outer peripheral surface of the doctor roller 9 are surely brought into contact with each other, and the ink reservoir 11 is surely contacted as in the first embodiment.
Can be sealed.

FIG. 5 is a schematic side view showing a main part inside the plate cylinder showing a second embodiment of the present invention. In this embodiment, the same parts as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. A rotary solenoid 20 is provided above the doctor roller 9 on the left side. The rotary solenoid 20 is attached to the outside of the side plate 6 on the back side, the output shaft 20a thereof penetrates through the side plate 6, and the tip thereof is rotatably supported by the side plate 7.

An ink absorbing member 21 is attached to the output shaft 20a. As shown in FIG. 7, the ink absorbing member 21 is composed of an arm member 22 and a porous member 23. The arm member 22 is a plate member, and a base portion 22a is formed at one end portion thereof, and a bent portion 22b is formed by bending the free end portion in a hook shape. The base 22a is the output shaft 2
0a and is rotatably supported. An operating piece 22c extending in the vertical direction is integrally erected on the upper surface of the base portion 22a near the side plate 6. One end of a tension spring 24 is engaged with the free end of the operating piece 22c, and the other end of the tension spring 24 is fixed to the side plate 6. Bending part 2
2b has a circular arc shape bent downward, and the circular arc is formed such that the center position is the center of the output shaft 20a. A flexible porous member 23 is bonded to the outer surface of the bent portion 22b. The porous member 23 is made of sponge, sponge, felt, or the like, and has an arc shape concentric with the bent portion 22b. Lower end 23 of porous member 23
The a is formed to have the same shape as the ink reservoir 11, that is, to be in close contact with the outer peripheral surfaces of the ink roller 8 and the doctor roller 9.

A diaphragm member 25 is disposed to the right of the ink absorbing member 21. The diaphragm member 25 is a roller, and is rotatably supported by a support shaft 25a provided between the side plates 6 and 7. The arrangement position of the diaphragm member 25 is such that the ink absorbing member 21 and the lower end portion 23a of the porous member 23 are located at the ink roller 8 and the doctor roller 9 as shown in FIG.
Of the rotary solenoid 20 from the first position, which is in close contact with the outer peripheral surface of the rotary roller 20, to the second position, in which the lower end portion 23a of the porous member 23 is separated from the outer peripheral surfaces of the ink roller 8 and the doctor roller 9 as shown in FIG. It is arranged at a position where it comes into pressure contact with the porous member 23 when it is rotated by rotation.

The operation of the second embodiment based on the above configuration will be described below. When the plate cylinder 1 is mounted on the stencil printer main body and the rotary solenoid 20 is electrically connected by connecting a connector or the like, the rotary solenoid 20
Rotates counterclockwise, and the arm member 22 and the porous member 23 move to the second position shown in FIG. At this time, the ink absorbed by the porous member 23 is squeezed out by the pressing of the squeezing member 25 and falls, forming the ink reservoir 11.

After that, printing is performed, but if a trouble such as a paper jam or a paper discharge jam occurs during printing, a control device (not shown) displays an alarm on the operation panel of the stencil printing machine and causes the rotary solenoid 20 to operate. Turn off the power supply. Then, the arm member 22 is rotated clockwise by the urging force of the tension spring 24, and the porous member 23 moves to the first position shown in FIG. Then, the lower end portion 23a of the porous member 23 contacts the outer peripheral surface of the ink roller 8 and the outer peripheral surface of the doctor roller 9, respectively, and absorbs the ink in the ink reservoir 11. Also, when the plate cylinder 1 is removed from the stencil printing apparatus main body during printing, when the rotary solenoid 20 is electrically disconnected, the arm member 22 is rotated clockwise in the same manner as described above, and the porous member 23 is rotated. The lower end portion 23a absorbs the ink in the ink reservoir 11.

[0024]

According to the first aspect of the present invention, since the openable and closable shield plate seals the ink reservoir, when the plate cylinder is removed from the stencil printing machine, a soft ink with good fluidity is used. However, it is possible to prevent the inside of the plate cylinder or the inside of the printing device from being contaminated due to the scattering and dropping of the ink. Further, when the printing apparatus is not used, the ink can be prevented from evaporating by sealing the ink reservoir with the shielding plate, and the ink which is easy to dry can be used without trouble. Furthermore, when removing the plate cylinder for storage,
Even if the plate cylinder is placed in an inclined state, it is possible to prevent stains inside the plate cylinder.

According to the second aspect of the invention, when the porous member occupies the first position where it contacts the outer peripheral surface of the ink roller and the outer peripheral surface of the doctor roller respectively, the ink in the ink reservoir is absorbed. When the plate cylinder is detached from the stencil printing machine, even if a soft ink having good fluidity is used, it is possible to prevent the ink from being scattered and the inside of the plate cylinder or the printing machine from being contaminated due to dripping. Further, when the plate cylinder is removed and stored, the inside of the plate cylinder can be prevented from being soiled even if the plate cylinder is placed in an inclined state.

[Brief description of drawings]

FIG. 1 is a schematic side view showing a main part of a plate cylinder of a stencil printing apparatus adopting a first embodiment of the present invention.

FIG. 2 is a partial perspective view illustrating the first embodiment of the present invention.

FIG. 3 is a partial perspective view of a shield plate showing another embodiment of the first embodiment of the present invention.

FIG. 4 is a partial perspective view of a shield plate showing another embodiment of the first embodiment of the present invention.

FIG. 5 is a schematic side view showing a main part of a plate cylinder of a stencil printing machine adopting a second embodiment of the present invention.

FIG. 6 is a schematic side view of a main part of a plate cylinder for explaining a second embodiment of the present invention.

FIG. 7 is a partial perspective view illustrating a second embodiment of the present invention.

[Explanation of symbols]

 1 plate cylinder 6,7 side plate 8 ink roller 9 doctor roller 10 ink supply means (supply nozzle) 11 ink reservoir 12,18,19 shielding plate 23 porous member 25 squeezing member

Claims (2)

[Claims] 1. A porous cylindrical cylinder which is rotatable and is arranged so that an outer peripheral surface abuts on an inner peripheral surface of the plate cylinder, and is rotatably supported by a side plate inside the plate cylinder. An ink roller, a doctor roller supported by the side plate, the outer peripheral surface of the doctor roller being arranged close to the outer peripheral surface of the ink roller, the outer peripheral surface of the ink roller, and the outer peripheral surface of the doctor roller. In the stencil printing machine having an ink supply means for supplying ink to the ink reservoir of the wedge-shaped space formed by the above, a stencil plate supported by the side plate and capable of closing the ink reservoir is provided. Stencil printer. 2. A porous cylinder-shaped rotatable plate cylinder, which is arranged so as to contact an outer peripheral surface with an inner peripheral surface of the plate cylinder, and is rotatably supported by a side plate in the plate cylinder. An ink roller, a doctor roller supported by the side plate, the outer peripheral surface of the doctor roller being arranged close to the outer peripheral surface of the ink roller, the outer peripheral surface of the ink roller, and the outer peripheral surface of the doctor roller. In the stencil printing machine comprising an ink supply means for supplying ink to the ink reservoir of the wedge-shaped space formed by the above, in the wedge-shaped space, the ink roller outer peripheral surface and the doctor roller outer peripheral surface are supported by the side plate. The first position is in contact with each other, and the second position is separated from the outer peripheral surface of the ink roller and the outer peripheral surface of the doctor roller. A porous member that absorbs ink in the ink reservoir when it occupies a position; and a porous member that is supported by the side plate and moves when the porous member moves from the first position to the second position. A stencil printing apparatus, comprising: a diaphragm member provided at a position where the stencil is pressed against the stencil.