JPH06297688A - Ink supply device in screen printing machine - Google Patents

Abstract

PURPOSE:To provide an ink supply device capable of surely recovering the ink bonded to the respective end surfaces of an ink roller by simple constitution and capable of rapidly recovering the recovered ink to an ink sump without accumulating the same on the inside surface of a side plate. CONSTITUTION:An ink supply device 20 has a pair of the side plates 7 arranged so as to be capable of coming into contact with the respective end surfaces of a doctor roll 6 and an ink roller 5 and a wedge-shaped ink sump 8. Each of the side plates 7 has the slide contact surface 12 coming into contact with each of the end surfaces of the ink roller in a slidable manner and a recessed part 13 not coming into contact with each of the end surfaces and an ink scraping surface 14 inclined in the rotary direction of the ink roller from the center of rotation thereof and inclined toward the boundary of the slide contact surface and the recessed part from the recessed part is formed to the boundary of the slide contact surface and the recessed part and the angle formed by the ink scraping surface 14 and the end surface of the ink roller is set to an obtuse angle.

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, and more particularly to an ink supply device installed inside a plate cylinder of the stencil printing machine.

[0002]

2. Description of the Related Art A plate cylinder composed of a porous support cylinder and a screen layer around which a base paper for stencil printing is wound, and an ink supply means for supplying ink to the inner peripheral surface of the plate cylinder. , Having a pressing means composed of a press roller provided opposite to the plate cylinder, the pressing means against the plate-making base paper wound around the outer peripheral surface of the plate cylinder, continuously press the printing paper, There is known a stencil printing apparatus that prints by allowing ink to seep out from the apertures of the plate cylinder and the perforations of the base paper. The ink supply means of the stencil printing machine includes an ink roller which is arranged so as to be in contact with the inner peripheral surface of the plate cylinder parallel to the axis of the plate cylinder and rotatable in synchronization with the rotation of the plate cylinder, and an outer peripheral surface of the ink roller. A doctor roller disposed with a slight gap therebetween, a pair of side plates slidably contacting each end face of the ink roller and each end face of the doctor roller, and inner side faces of each side plate. And a wedge-shaped ink reservoir formed on the above-mentioned gap so as to surround each end surface region thereof, and ink is supplied to the outer peripheral surface of the ink roller. During printing, the printing roller is pressed against the plate cylinder by a pressing means such as a press roller during printing, and the ink roller comes into close contact with the inner peripheral surface of the plate cylinder, causing the ink supplied to the outer peripheral surface of the ink roller to seep out from the openings of the plate cylinder. However, not all of the ink supplied at this time is consumed through the openings, but it collects on the outer peripheral surface of the ink roller while collecting at the contact area between the ink roller and the inner peripheral surface of the plate cylinder. A part of the ink sticks out from the end of the ink roller, adheres to each end surface of the ink roller, and is collected. The ink that adheres to and collects on the outer peripheral surface of the ink roller is returned to the ink reservoir as it is and is gradually consumed for printing, but there is no problem, but the ink that adheres to each end surface of the ink roller does not If the lower surface of the side plate that is in sliding contact with the end surface is a flat surface, it is scraped off from each end surface of the ink roller and accumulated on the lower surface of the side plate. There is a problem that stains the mechanical part of.

Therefore, in order to solve the above-mentioned problems, for example, as shown in Japanese Patent Publication No. 2-24667, a concave portion in which each end surface of the ink roller does not substantially contact the inner surface of each side plate is formed. While being provided on the side plate, each of the second regions that does not substantially contact the inner surface of each side plate to the boundary along the line that is displaced in the rotation direction of the ink roller as it goes radially outward from the rotation center of the ink roller. A wedge-shaped space is formed between each end surface of the ink roller by inclining toward the first area that is substantially in sliding contact with the inner surface of the side plate along the direction of rotation of the ink roller so as to gradually approach each end surface of the ink roller. A technique has been proposed in which the ink on each end face of the ink roller is collected in this wedge-shaped space by partitioning.

Further, since each end face region of the ink fountain is in contact with the inner side face of each side plate, the viscous resistance of the contact portion is increased and the collected ink is stuck to the inner side face, that is, the collected ink. The rotational flow of ink becomes unstable,
Therefore, the recovery of the ink in the ink reservoir becomes unstable, and the recovered ink easily accumulates on the inner surface of the side plate, and if the device is used for a long time, the accumulated ink may not reach the ink recovery state. Therefore, in order to solve this problem, for example, as disclosed in Japanese Utility Model Laid-Open No. 62-189129, a bar-shaped member is provided in the ink reservoir and the bar-shaped member is forcibly driven to rotate by a compulsory driving device. Techniques have been proposed.

[0005]

However, in the former case, the ink usually used is a water-in-oil type ink in which water is surrounded by oil, and the oil component thereof generally enters a narrow portion. Since lubricating oil such as machine oil, which has an easy property, is used, the ink in the ink pool surrounded by the inner surface of each side plate and the wedge-shaped space cannot be blocked reliably, and the end surface of each ink roller is gradually blocked. Since the angle formed by the end surface of the ink roller and the surface inclined in the direction of approaching the ink roller is an acute angle, the ink adhered to each end surface of the ink roller is not actively scraped by the inclined surface, and It gets in between the end surface and the inner surface of each side plate. When the ink enters in this way, the side plate is spread outward, and the ink in the ink pool adheres to each end surface of the ink roller and drops, depending on the rotation of the ink roller, or adheres to the end surface of each side plate on the lower side of the doctor roller. There is a problem that the inside of the plate cylinder is contaminated by falling and scattering as a lump. Further, the scattered ink is not used for printing and is wasted, and if it is collected on an inclined surface adjacent to the wedge-shaped space provided on the side plate, it cannot be recovered, and the same problem as described above occurs. Therefore, it is desirable that the ink quickly moves from the ink collecting section to the ink pool section.

Further, in the latter, there is a problem that the mechanism becomes complicated and the cost increases.

Therefore, according to the present invention, in order to solve such a problem, the ink adhering to each end surface of the ink roller can be reliably collected by a simple device, and the collected ink is accumulated on the inner surface of the side plate. It is an object of the present invention to provide an ink supply device in a stencil printing device that can be quickly collected in an ink reservoir without doing so.

[0008]

In order to achieve the above-mentioned object, according to the invention of claim 1, a rotatable porous cylindrical plate cylinder provided with a passage structure for the ink supplied to the inner peripheral surface. An ink roller disposed inside the plate cylinder and rotatable in synchronism with the rotation of the plate cylinder; a doctor roller arranged with a slight gap from the outer peripheral surface of the ink roller; In a stencil printing machine having a pair of side plates disposed so as to be in contact with the respective end faces of the ink roller, and a wedge-shaped ink reservoir formed on the gap so as to surround the respective end face regions on the inner side surface of the respective side plates. In the ink supply device, each of the side plates has a slide contact surface that is in sliding contact with each end surface of the ink roller, and a recess that does not slide in contact with each end surface, and at the boundary between the slide contact surface and the recess. , Rotation of the ink roller when viewed in the direction of rotation An ink scraping surface inclined toward the boundary from the recess with inclined sincerely in the rotational direction is formed, and set an angle between the ink scraping surface and the end face of the ink roller at an obtuse angle.

According to a second aspect of the invention, in the ink supply device of the stencil printing apparatus according to the first aspect, an ink returning surface is provided continuously to the ink scraping surface, and the ink returning surface is provided in each of the end face regions. Placed in close proximity or polymerized.

According to a third aspect of the invention, a rotatable porous cylindrical plate cylinder provided with a passage structure for the ink supplied to the inner peripheral surface thereof, and the plate cylinder disposed inside the plate cylinder are provided. An ink roller rotatable in synchronism with the rotation, a doctor roller arranged with a slight gap from the outer peripheral surface of the ink roller, and a pair of contact rollers arranged so as to be in contact with each end surface of the ink roller. A side plate, a wedge-shaped ink reservoir formed on the gap so as to surround each end face region on the inner side surface of each side plate, and an ink collecting means for collecting ink from each end face of the ink roller to the ink reservoir. In an ink supply device in a stencil printing machine having, on each of the inner side surfaces where each end face region of the ink reservoir comes into contact, when the ink is a water-in-oil type ink, hydrophilicity, when the ink is an oil-in-water type ink Water repellent in some cases A coating layer made of a material having each were substantially formed. Here, “substantially forming a coating layer” means that the material is formed by a film forming method such as vapor deposition, sputtering, ion plating, plating, or coating, or a coating made of the material is adhered to the inner surface. It means that a layer is formed.

According to a fourth aspect of the invention, a rotatable cylindrical cylinder plate cylinder having a structure for passing ink supplied to the inner peripheral surface thereof, and a plate cylinder arranged inside the plate cylinder are provided. An ink roller rotatable in synchronism with the rotation, a doctor roller arranged with a slight gap from the outer peripheral surface of the ink roller, and a pair of contact rollers arranged so as to be in contact with each end surface of the ink roller. A side plate, a wedge-shaped ink reservoir formed on the gap so as to surround each end face region on the inner side surface of each side plate, and an ink collecting means for collecting ink from each end face of the ink roller to the ink reservoir. In the ink supply device of the stencil printing machine having the above, a synthetic resin layer having a property of repelling both water and oil is substantially formed on each of the inner side surfaces with which each end surface region of the ink reservoir comes into contact. Here, substantially forming the synthetic resin layer means forming the synthetic resin layer by a film forming method such as coating the synthetic resin or by adhering a coating film made of the material to the inner surface. .

[0012]

According to the first aspect of the present invention, in each side plate, the boundary between the sliding contact surface and the concave portion is inclined in the rotational direction from the center of rotation of the ink roller when viewed in the rotational direction of the ink roller, and is inclined from the concave portion toward the boundary. Since the ink scraping surface is formed and the angle between the ink scraping surface and the end surface of the ink roller is set to an obtuse angle, the ink adhering to each end surface of the ink roller is scooped by the obtuse ink scraping surface. Be sure to be scraped off as if it were.

According to the second aspect of the present invention, the ink returning surface is provided continuously to the ink scraping surface, and the ink returning surface is arranged close to or superposed on each end face region of the ink fountain. The ink adhering to each end surface is reliably scraped off and collected by the obtuse-shaped ink scraping surface, and the collected ink moves on the ink scraping surface and the continuous ink returning surface Thus, the recovered ink is returned to the ink reservoir and recovered.

According to the third aspect of the invention, the inner surface of the side plate with which the end surface regions of the ink reservoir contact each other has hydrophilicity when the ink is a water-in-oil type ink, and the ink is an oil-in-water type ink. In this case, since the coating layers each having water repellent property are substantially formed, the contact viscosity resistance between the recovered ink recovered by the ink recovery means and each inner surface of the side plate becomes small, and the recovered ink is recovered by each side plate. It is not collected on the inner surface, but is quickly collected in the ink reservoir.

According to the fourth aspect of the invention, since the synthetic resin layer having the property of repelling both water and oil is substantially formed on each inner surface of the side plate with which each end surface region of the ink reservoir contacts, the ink is formed. The contact viscous resistance between the recovered ink recovered by the recovery means and each inner surface of the side plate is reduced, and the recovered ink is not collected on each inner surface of the side plate and is promptly recovered in the ink reservoir.

[0016]

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

First, with reference to FIG. 5, description will be given of a main configuration of a stencil printing apparatus to which the present invention is applied. In the figure, reference numeral 1 indicates a porous cylinder plate cylinder. The plate cylinder 1 has a predetermined width in the axial direction of the center of rotation, and a support cylinder 1A having an ink passage portion 1b having a large number of openings 1a and an ink non-passage portion 1c, and It is mainly composed of an ink-permeable mesh screen 1B that covers the outer peripheral surface of the support cylinder 1A. The region where the ink passage portion 1b and the mesh screen 1B are superposed constitutes a passage structure for the ink supplied to the inner peripheral surface of the plate cylinder 1. Plate cylinder 1
The ink pipe 4 that also serves as the central axis of rotation is driven to rotate in a clockwise direction indicated by an arrow by a motor driving device (not shown). A clamper 2 is provided on the outer peripheral surface of the support cylinder 1 of the ink impermeable portion 1c of the plate cylinder 1 to lock a pre-processed base paper 3 for stencil printing. The base paper 3 is sandwiched and held on the outer peripheral surface thereof by the viscosity of the ink supplied.

Inside the plate cylinder 1, an ink pipe 4, an ink roller 5, a doctor roller 6, a side plate 7 and an ink reservoir 8 are provided.
An ink supply device 20 is provided. The ink roller 5 is rotatably supported by a supporting side plate (not shown), has a length substantially the same as the width of the ink passing portion 1b of the supporting cylinder 1A, and has a slight clearance from the inner peripheral surface of the supporting cylinder 1A. It is provided with. The ink roller 5 is rotationally driven in the same direction as the rotation direction of the plate cylinder 1 by a drive device (not shown) in synchronization with the rotation of the plate cylinder 1. Doctor roller 6
Is rotatably supported by a supporting side plate (not shown) with a slight gap from the outer peripheral surface of the ink roller 5, and meshes with a gear (not shown) provided at one end of the rotating shaft 5s of the ink roller 5 (not shown). The rotation transmission member formed of a gear is rotationally driven in the direction opposite to the ink roller 5, that is, in the arrow direction (counterclockwise direction). Doctor roller 6
It is arranged parallel to the rotating shaft 5s of the ink roller 5,
An ink pipe 4 having an opening 4h facing downward is arranged above the ink roller 5, and ink is supplied from the opening 4h to the doctor roller 6 and the ink roller 5.
An ink reservoir 8 having a wedge-shaped cross section is formed on the gap formed on the outer peripheral surface of the ink. The ink used in this example is a water-in-oil type ink in which water is surrounded by oil.

As shown in FIGS. 1 and 4, the ink reservoir 8
The ink is strongly affected by the inertial flow of the rotational force of the ink roller 5, and is rotationally moved in the counterclockwise direction indicated by the arrow opposite to the rotational direction of the ink roller 5. The ink in the ink reservoir 8 passes through a minute gap between the ink roller 5 and the doctor roller 6, so that a uniform ink film is formed on the outer peripheral surface of the ink roller 5.

A pair of side plates 7 are arranged between each end face of the ink roller 5 and a supporting side plate (not shown), and each inner side surface 7a of each side plate 7 and each end face of the ink roller 5 are connected to each other. It is provided so as to be elastically slidable while maintaining a contact pressure that does not hinder the rotation of 5. The vicinity of each end of the doctor roller 6 is rotatably supported by a supporting side plate (not shown) while penetrating each side plate 7 while maintaining a contact pressure that does not hinder the rotation of the doctor roller 6. Each side plate 7 is fixed to a supporting side plate (not shown) at the predetermined position inside the plate cylinder 1. The wedge-shaped ink fountain 8 is formed such that each end surface region thereof is surrounded by each inner side surface 7 a of each side plate 7. Regarding the configuration of each side plate 7 of the ink supply device described below, only one side shown in the figure will be described unless otherwise specified.

1 and 5, the side plate 7 is formed with a sliding contact surface 12 that is in sliding contact with the end surface of the ink roller 5, and a recess 13 that is not in sliding contact with the end surface of the ink roller 5. The boundary between the sliding contact surface 12 and the concave portion 13 is inclined in the rotational direction from the rotation center of the ink roller 5 when viewed in the rotational direction (clockwise direction) indicated by the arrow, and the concave portion 13 is formed.
The ink scraping surface 14 is formed so as to incline toward the boundary. As shown in FIG. 2, the angle A formed between the ink scraping surface 14 and the end surface of the ink roller 5 is 1
It is set to about 10 ° to 150 °. An ink returning surface 15 is provided continuously from the upper part of the recess 13 to the ink scraping surface 14 and not slidably contacting the end face of the ink roller 5 and inclined from the recess 13 toward the inner side surface 7a. The ink return surface 15 is arranged close to the end face region of the ink fountain 8.

Here, the angle A formed between the ink scraping surface 14 and the end surface of the ink roller 5 is preferably about 110 ° to 150 °, but is not limited to this and may be at least an obtuse angle.

As described in the prior art, for example, referring to FIG. 4, in each end face region of the ink reservoir 8, the viscous resistance of the contact portion in contact with the inner side face 7a of each side plate 7 is large. Therefore, the ink supply device 2 of the above embodiment
The collected ink collected by No. 0 is attached to the inner surface 7a, that is, the ink reservoir 8 and the inner surface 7 shown in FIG.
Contrary to the ink edge area 8a with respect to a, a wedge shape is formed in which the inner side surface 7a side is wider than the wedge shape of the ink reservoir 8 near the center, and the rotational flow of the ink reservoir edge is unstable. Therefore, the recovery of the ink in the end face region of the ink fountain 8 becomes unstable, and the recovered ink is collected by the side plate 7.
The ink easily deposits on the inner side surface 7a of the ink, and if the device is used for a long time, the ink accumulates and the ink cannot be recovered.

Therefore, in order to eliminate the above-mentioned problems, FIG.
In addition to the structure of the ink supply device 20, the inner surface 7a of the ink reservoir 8 in contact with each end surface region corresponds to the ink used, that is, water-in-oil type ink, such as chromium. A coating layer 16 (shown by hatching in the figure) made of a metal hydrophilic material is coated. In FIG. 4, in order to clarify the operation, so-called ink collecting means such as the concave surface 13, the ink scraping surface 14, the ink returning surface 15 and the like are omitted.

In FIG. 5, a press roller 9 is arranged near the lower side of the outer peripheral surface of the plate cylinder 1 facing the ink roller 5, and the press roller 9 is swingably provided by a support shaft (not shown). Arm (not shown)
It is rotatably supported by and selectively occupies a printing position in which it is pressed against the outer peripheral surface of the plate cylinder 1 via a printing sheet (not shown) and a non-printing position separated from the outer peripheral surface of the plate cylinder 1. The press roller 9 is held at a non-printing position separated from the outer peripheral surface of the plate cylinder 1 except when the paper is passed. On the right side of the press roller 9 in the figure, a pair of upper and lower registration rollers 10a and 10b for delivering printing paper (not shown) at a predetermined timing are arranged between the plate cylinder 1 and the press roller 9.

On the left side of the press roller 9 in the drawing, printed paper (not shown) is attached from the outer peripheral surface of the plate cylinder 1 attached to a shaft 11s rotatably supported by a stationary member of a stencil printing machine (not shown). ) Is peeled off, the peeling claw 11 is provided substantially integrally. The peeling claw 11 interlocks with the contact / separation operation of the press roller with respect to the plate cylinder 1, and separates a printed sheet (not shown) from the outer peripheral surface of the plate cylinder 1 (shown by phantom lines in the figure) and a clamper. It is swingably disposed between a non-separation position (indicated by a solid line in the figure) for avoiding interference with 2.

Next, the operation of the stencil printing machine to which this embodiment is applied will be described. In FIG. 5, the preprinted base paper 3
After the sheet is wound around the outer peripheral surface of the plate cylinder 1, the printing process is started. A print sheet (not shown) is fed to the registration roller pair 10a, 10b from the upstream side of a sheet feeding device (not shown), and the registration roller pair 10a, 10b takes a predetermined timing synchronized with the rotation of the plate cylinder 1. A printing paper (not shown) is inserted between the plate cylinder 1 and the press roller 9. Then, the detection device (not shown) that restricts the contact / separation operation of the press roller 9 is released, whereby the arm (not shown) swings upward, and the press roller 9 moves upward as shown by the phantom line. The base paper 3 wound around the outer peripheral surface of the plate cylinder 1 rotating in the arrow direction (clockwise direction) is pressed via a printing paper (not shown). Thus, the ink supplied by the ink roller 5 arranged so as to be able to contact the inner peripheral surface of the plate cylinder 1 passes through the openings 1a of the supporting cylinder 1A and the mesh screen 1B to the base paper 3 to be exuded and printed. Printing is performed on a sheet (not shown). Then, the printed printing paper (not shown) is peeled off from the outer peripheral surface of the plate cylinder 1 by the peeling claw 11 occupying the separation position shown by the phantom line, and is discharged to a discharge tray (not shown). When the plate cylinder 1 is further rotated, the clamper 2 approaches the vicinity of the press roller 9, and the cam mechanism (not shown) causes the arm (not shown) to swing downward as shown by the solid line, so that the press roller 9 is rotated.
Occupies the non-printing position apart from the outer peripheral surface of the plate cylinder 1. When the plate cylinder 1 is further rotated, the clamper 2 peels off the nail 11.
The peeling claw 11 occupies the non-separated position indicated by the solid line in the vicinity of the position.

When the press roller 9 occupies the printing position in the above-described operation, the press roller 9 presses the outer peripheral surface of the plate cylinder 1 via the printing paper (not shown), so that the ink roller 5 and the plate cylinder are pressed. The ink supplied from the outer peripheral surface of the ink roller 5 accumulates on the upstream side of the contact portion between the ink roller 5 and the inner peripheral surface of the plate cylinder 1. A part of the accumulated ink protrudes from each end surface portion of the ink roller 5 and adheres to the end surface of the ink roller 5.

In FIG. 1 or FIG. 2, the ink adhering to the end surface of the ink roller 5 is scraped off by the ink scraping surface 14 while being scraped off by the rotational force of the ink roller 5 and the outer circumference of the ink roller 5. Surface side, that is, rises along the ink scraping surface 14, and slightly past the outer peripheral surface of the ink roller 5, that is, to the ink returning surface 15 arranged continuously with the ink scraping surface 14. The ink is guided and moved, and the ink is collected from the ink returning surface 15 to the end surface area of the ink reservoir 8. The recovered ink is repelled by the chromium metal coating layer coated on the end surface region of the ink reservoir 8 on the inner surface 7a, the contact viscosity resistance of the ink is reduced, and the ink does not stick to the inner surface 7a around it. The ink is promptly collected in the ink reservoir 8. Then, as shown in FIG. 4, the rotational flow of the ink fountain 8 in the direction of the arrow is smoothly performed, and the wedge shape of the end face region of the ink fountain 8 is small, that is, the ink end region 8a having a tapered wedge shape is formed. To be done. The ink thus collected in the ink reservoir 8 is kneaded with the ink in the ink reservoir 8 and gradually consumed during printing.

FIG. 3 shows an ink supply device 20A as a modification of the above embodiment. In this figure, this ink supply device 20A is
By raising the boundary between the ink scraping surface 14A and the sliding contact surface 12 by Δa and pressing the end surface of the ink roller 5,
The only difference is that the contact pressure of the boundary area with the end surface of the ink roller 5 is increased. In this way, the boundary between the ink scraping surface 14A and the sliding contact surface 12 is Δa, for example,
By bulging 0.05 to 0.1 mm, the effect of scraping the ink adhering to the end surface of the ink roller 5 can be further improved.

The material of the coating layer 16 is not limited to the above-mentioned embodiment, and when the ink used in the ink supply device is an oil-in-water type of a type in which oil is surrounded by water, it repels water, For example, a coating film made of a material having water repellency such as acetal resin may be formed.

The material of the coating layer 16 is not limited to the above-mentioned embodiment, and is coated with a synthetic resin layer having a property of repelling both water and oil, such as tetrafluoroethylene polymer (trade name: Teflon). May be.

Further, the formation of the coating layer 16 is not limited to the application to the ink supply device 20 described above, and the ink supply device 20A or any other known method for collecting the ink from each end surface of the ink roller to the ink reservoir. It may be an ink supply device having an ink collecting means using a technique, for example, Japanese Patent Publication No. 2-24667 or Japanese Patent Application No. 4-287762 already filed by the same applicant.

The ink return surface 15 is not limited to be arranged close to each end face region of the ink fountain 8 shown in FIGS. 1 and 5, but may be superposed on the end face region of the ink fountain 8. .

[0035]

As described above, according to the first aspect of the invention, in each side plate, the boundary between the sliding contact surface and the concave portion is inclined in the rotation direction from the rotation center of the ink roller when viewed in the rotation direction. At the same time, by forming an ink scraping surface that inclines from the recess toward the boundary, and by setting the angle between the ink scraping surface and the end surface of the ink roller to be an obtuse angle,
Even if the ink is oil-in-water type or oil-based ink, or even the type of ink that easily enters the gap such as lubricating oil, the ink adhering to each end surface of the ink roller is reliably scraped off by the obtuse-angled ink scraping surface. It is possible to prevent the ink from being collected and not deposited in the vicinity of each end surface of the ink roller without being collected, and to prevent the mechanical portion inside the plate cylinder from being soiled and the ink from being wasted by a simple device.

According to the second aspect of the present invention, the ink returning surface is provided continuously to the ink scraping surface, and the ink returning surface is arranged close to or superposed on each end face region of the ink fountain. The ink adhering to each end surface of the is scraped off by the obtuse-angled ink scraping surface, and collected, and the collected ink moves on the ink scraping surface and is continuously returned to this. Since the collected ink is smoothly returned to the ink reservoir by the surface and is collected, in addition to the effect of the invention described in claim 1, ink is not accumulated on the ink scraping surface, and the inside of the plate cylinder It is possible to prevent stains on the mechanism part and waste of ink by a simple device.

According to the third aspect of the present invention, the inner surface of the side plate with which each end surface region of the ink reservoir comes into contact has hydrophilicity when the ink is a water-in-oil ink, and the ink is an oil-in-water ink. In this case, by substantially forming the coating layer made of a material having water repellent property, the contact viscosity resistance between the recovered ink recovered by the ink recovery means and each inner surface of the side plate becomes small, and the recovered ink is recovered. Is not accumulated on each inner surface of the side plate and is quickly collected in the ink fountain,
Ink can be prevented from accumulating in the ink collecting portion of the ink collecting means, and the mechanical portion inside the plate cylinder can be prevented from becoming dirty and the ink can be prevented from being wasted with a simple device at low cost.

According to the fourth aspect of the present invention, the synthetic resin layer having the property of repelling both water and oil is substantially formed on each inner side surface of the side plate with which each end surface region of the ink reservoir contacts. The contact viscous resistance between the recovered ink recovered by the ink recovery means and each inner surface of the side plate becomes small, and the recovered ink is not collected on each inner surface of the side plate and is quickly recovered in the ink reservoir. The ink does not accumulate in the ink collecting portion of the ink collecting means even when used, and it is possible to inexpensively prevent the mechanism inside the plate cylinder from becoming dirty and the ink from being wasted by a simple device.

[Brief description of drawings]

FIG. 1 is a perspective view of a main part of an ink supply device showing an embodiment of the present invention.

FIG. 2 is a plan sectional view of a main part of FIG.

FIG. 3 is a plan sectional view of a main part of an ink supply device showing a modified example of FIGS. 1 and 2.

FIG. 4 is a perspective view supplementing the configuration and operation of FIG.

5 is a side view of a main portion of a stencil printing apparatus to which the embodiment of FIG. 1 is applied.

[Explanation of symbols]

A Angle formed between the ink scraping surface and the end surface of the ink roller 1 Plate cylinder 4 Ink pipe 5 Ink roller 6 Doctor roller 7 Side plate 7a Inner side surface 8 Ink reservoir 8a Ink end area 12 Sliding contact surface 13 Concave surface 14 and 14A Ink scraping Surface 15 Ink return surface 16 Coating layer 20, 20A Ink supply device

Claims (4)

[Claims] 1. A rotatable cylindrical cylinder plate cylinder having a structure for passing ink supplied to an inner peripheral surface thereof, and a plate cylinder disposed inside the plate cylinder and rotating in synchronization with the rotation of the plate cylinder. Possible ink rollers, a doctor roller arranged with a slight gap from the outer peripheral surface of the ink roller, a pair of side plates disposed so as to be in contact with the respective end faces of the ink roller, and the side plates. In an ink supply device in a stencil printing machine having inner end surfaces surrounded by the respective end surface regions and having a wedge-shaped ink reservoir formed on the gap, each side plate is in sliding contact with each end surface of the ink roller. A surface and a concave portion that does not come into sliding contact with each of the end faces, and at the boundary between the sliding contact surface and the concave portion, inclined from the rotation center of the ink roller in the rotation direction when viewed in the rotation direction, and A sloped from the recess toward the boundary An ink supply device in a stencil printing machine, characterized in that an ink scraping surface is formed, and an angle formed between the ink scraping surface and the end surface of the ink roller is set to an obtuse angle. 2. The ink supply device for a stencil printing apparatus according to claim 1, wherein an ink returning surface is provided continuously to the ink scraping surface, and the ink returning surface is arranged close to or overlaps with each end face region. An ink supply device in a stencil printing machine, characterized in that 3. A rotatable porous cylindrical plate cylinder having a structure for passing ink supplied to the inner peripheral surface thereof, and a plate cylinder arranged inside the plate cylinder and rotating in synchronization with the rotation of the plate cylinder. Possible ink rollers, a doctor roller arranged with a slight gap from the outer peripheral surface of the ink roller, a pair of side plates disposed so as to be in contact with the respective end faces of the ink roller, and the side plates. In a stencil printing apparatus having a wedge-shaped ink reservoir formed on the gap so as to surround each end face region on the inner side surface of the ink and ink collecting means for collecting ink from each end face of the ink roller to the ink reservoir. In the supply device, on each of the inner side surfaces where each end surface area of the ink reservoir comes into contact, when the ink is a water-in-oil type ink, hydrophilicity,
When the above-mentioned ink is an oil-in-water ink, an ink supply device in a stencil printing machine is characterized in that a coating layer made of a material having water repellent property is substantially formed. 4. A rotatable porous cylindrical plate cylinder provided with a structure for passing ink supplied to the inner peripheral surface, and arranged inside the plate cylinder and rotating in synchronization with the rotation of the plate cylinder. Possible ink rollers, a doctor roller arranged with a slight gap from the outer peripheral surface of the ink roller, a pair of side plates disposed so as to be in contact with the respective end faces of the ink roller, and the side plates. In a stencil printing apparatus having a wedge-shaped ink reservoir formed on the gap so as to surround each end face region on the inner side surface of the ink and ink collecting means for collecting ink from each end face of the ink roller to the ink reservoir. In the supply device, a synthetic resin layer having a property of repelling both water and oil is substantially formed on each of the inner side surfaces with which each end face region of the ink reservoir comes into contact, and the ink supply device in a stencil printing apparatus. .