JPH01120382A - Liquid leak preventive device of stencil printer - Google Patents

Abstract

PURPOSE:To eliminate fouling on the interior of a device or plate discharge error by providing a weir between the peripheral surface of a cylindrical body with an ink supply device inside and paper and thereby preventing ink from leaking from a gap between a screen layer and the paper. CONSTITUTION:Stencil paper 14 with a tip 15 fitted to a paper attaching part 13 positioned at a non-perforated part 5 of a cylindrical body is wound around the peripheral surface of a screen layer 3. A weir 19 is formed at the end of a member 18 provided between the end part 1 and the non-perforated part 5 of the paper 14. Ink 10 supplied from a drum shaft 7 is rubbed into the perforated part 4 of the cylindrical body 2 by means of a roller 8, and further is printed on the surface of paper 20 after passing through the screen layer 3 and the paper 14. As printing further proceeds, the ink 10 arrives at a gap 21 between the screen layer 3 and the paper 14. After this, a press roller 17 rides over a part bulged by the weir 19 of the paper 14, pressing back the remaining ink 10 from the gap 21 to the cylindrical body 2. Thus the ink 10 is prevented from leaking into the exterior.

Description

[Detailed description of the invention] Technical field The present invention relates to a liquid leakage prevention device for a stencil printing device.

BACKGROUND OF THE INVENTION A conventional stencil printing apparatus is provided with a cylindrical body that rotates around an axis and has an apertured portion and a non-perforated portion on the side surface of the cylinder. An ink supply device is provided inside this cylindrical body and constantly supplies ink to the inside. Further, a screen layer is attached to the outer circumferential surface of the cylindrical body, and this screen layer is immersed in ink that is sent out from the opening of the cylindrical body. The outer peripheral surface of the screen layer is a plate whose tip is locked by a clamper provided in the non-opening part of the cylindrical body, and is pasted from the tip to the end by the viscosity of the ink of the screen layer. Completed stencil sheets are provided. Then, the printing paper is sequentially fed between the cylindrical body to which the stencil paper is pasted and a press roller that is rotatable in contact with the cylindrical body, and the ink supply roller provided inside the cylindrical body is fed to the outside. Printing is performed by performing a rubbing operation.

When printing using this method, ink is supplied through the screen layer from the apertures of the cylindrical body on the image surface, which is the perforated part of the stencil paper, and passes through the holes in the stencil paper to form the printing paper. The supplied ink is gradually consumed by the rubbing operation of the ink supply roller onto the printing paper.

However, at the non-perforated end portion of the stencil paper, even if ink is supplied from the apertures of the cylindrical body through the screen layer, the supplied ink is concentrated at the end portion. The ink collected at the end is pushed out by a press roller between the cylindrical side surface and the screen and between the screen and the stencil paper.
Furthermore, a phenomenon called "liquid leakage" occurs that leaks out from the gap between the screen and the end of the stencil paper, resulting in staining the printing paper, staining the inside of the machine, and the end of the stencil paper. It was not possible to prevent plate ejection errors caused by ink adhering to the screen.

Therefore, conventionally, as a method to prevent such a phenomenon of ink "liquid leakage", first, the pressure of the press roller is released when the stencil paper approaches the end of the stencil paper. .

However, in this case, especially if the ink is used in a soft state at high temperatures, excess ink may accumulate between the cylindrical body and the screen and between the screen and the stencil paper6. Some types have a dam installed between the non-perforated portion and the screen layer to prevent excess ink from spilling out. However, in this case, when used at high temperatures as mentioned above,
Although the accumulation of excess ink between the cylinder and the screen layer could be prevented, the accumulation of ink between the screen layer and the stencil paper could still not be prevented.

Purpose The present invention has been made in view of these points, and by providing a weir between the outer circumferential surface of the cylindrical body and the base paper, ink leakage occurring from the gap between the screen layer and the base paper is prevented, and the apparatus is improved. The purpose of the present invention is to obtain a liquid leakage prevention device for a stencil printing device that eliminates internal contamination and plate ejection errors.

Embodiment The present invention has a dam between the outer peripheral surface of the cylindrical body and the base paper to prevent ink from leaking to the outside, so that it is possible to prevent ink from leaking from the gap between the screen layer and the base paper. This makes it possible.

The structure is such that it is possible to eliminate contamination inside the apparatus, and also to prevent the end of the base paper from coming into close contact with the screen layer, thereby eliminating mistakes in plate discharge.

A first embodiment of the present invention will be described based on FIGS. 1 and 2. The cylindrical plate cylinder 1 consists of a support cylinder 2 as a cylinder, and a screen layer 3 attached to the outer peripheral surface of the support cylinder 2.

The support cylindrical body 2 is made of metal and has an aperture 4 and a non-aperture part 5 on its cylindrical side surface. The screen layer 3
is made of mesh-like polyester fibers.

Further, an ink supply device 6 is provided inside the cylindrical plate 1111. This ink supply device 6 includes a hollow drum shaft 7 provided at a central position and the cylindrical plate cylinder 1.
The ink supply roller 8 is in contact with the inner peripheral surface of the ink supply roller 8, and the doctor roller 9 is arranged on the outer peripheral surface of the ink supply roller 8 at a predetermined interval. The supplied ink 10 passes through the inside of the drum shaft 7 and is discharged from a plurality of holes 11 provided on the lower surface of the drum shaft 7, and is stored in the gap between the ink supply roller 8 and the doctor roller 9. form 12.

On the other hand, the support cylinder 2 is provided outside the cylindrical plate cylinder 1.
A base paper attachment part 13 is provided as a locking part, which is located in the non-opening part 5 and consists of a clamper using a rubber magnet. In this attachment of the base paper, the tip end 15 of the stencil paper 14 as the base paper is locked in the part 13, and the other part toward the terminal end 16 is attached to the outer peripheral surface of the screen layer 3 due to the viscosity of the ink 10. It is tightly wrapped. Further, a press roller 17 that is movable in the vertical direction and rotatable is provided in contact with the outer peripheral surface of the cylindrical plate cylinder 1.

Further, the terminal end 16 of the stencil paper 14 and the non-perforated part 5 of the support cylinder 2 are made of an ink-impermeable material to prevent the ink 10 from leaking to the outside. A weir forming member 18 as a tool is provided, and one end of this weir forming member 18 is provided with a terminal end 16 of the stencil paper 14.
A weir 19 is formed at this location.

In such a configuration, when ink 10 is supplied from the drum shaft 7 inside the cylindrical plate cylinder 1, an ink reservoir 12 is formed in the gap between the ink supply roller 8 and the doctor roller 9. This viscous ink reservoir 12 is sent out from the gap between these rollers 8 and 9 whose rotating directions are opposite to each other, adheres to the surface of the ink supply roller 8, and rotates in the direction of the arrow.

The ink 10 is then supplied to the screen layer 3 by being rubbed into the opening 4 of the support cylinder 2 by the ink supply roller 8, and furthermore, the ink 10 that has been rubbed is
0 passes through the gap between the screen layer 3 and is supplied to the back side of the stencil paper 14. After the supplied ink 10 passes through holes (not shown) that form the image surface of the stencil paper 14.

The image is transferred onto the surface of the printing paper 20 pressed by the press roller 17 and printed.

In this way, printing progresses sequentially while rotating.
When reaching the unperforated terminal end 16 of the stencil paper 14, the ink 10 impregnated in the supporting cylinder 2 and the screen layer 3 is sequentially sent toward the rear where the weir 19 is formed, and the ink 10 impregnated in the support cylinder 2 and the screen layer 3 is sequentially sent toward the rear where the weir 19 is formed. It reaches the gap 21 formed between the stencil paper 14 and the stencil paper 14 . Then, as the cylindrical plate cylinder 1 further rotates, the press roller 17, which can move in the vertical direction, rides on the part of the stencil paper 14 raised by the weir 19, and the ink 10 remaining in the gap 21 is moved in the direction of arrow a. Push it back toward the support cylinder 2 side as shown.

By providing the weir 19 in this manner, the ink 1o remaining in the gap 21 between the terminal end 15 of the stencil paper 14 and the screen layer 3 leaks to the outside. The phenomenon of so-called F liquid leakage J can be prevented.

Next, a second embodiment of the present invention will be described based on FIGS. 3 to 5. In this case, one end of the weir forming member 18 is 2
It is also divided into two parts, a first weir 22 on the support cylinder 2 side and a second part 23 on the stencil paper 14 side with the screen layer 3 in between.
Two dams have been formed.

In such a configuration, in order to effectively prevent "liquid leakage", it is necessary for the tip of the first weir 22 to be in contact with the opening 4 of the support cylinder 2.
and the non-opening part 5 side from the boundary position O of the non-opening part 5,
On the other hand, if the tip of the second section 23 is located closer to the opening 4 than the boundary position O, "liquid leakage" can be further prevented. This is because the ink 10 remaining in the gap 24 between the screen layer 3 formed by the second term 23 and the stencil paper 14 is absorbed by the gap 24 between the support cylinder 2 and the screen layer 3 formed by the second weir 22. This is because it has a two-stage structure in which the ink 10 moves toward the gap 25 and then pushes the ink 10 remaining in the gap 25 toward the supporting cylindrical body 2 side.

According to experimental results, the thickness of the first weir 22 and the second term 23 should normally be 0.3 m to 1 mm. Also,
Distance 111 from the tip of the second weir 22 to the tip of the second term 23
1d may be about 5 mm, and the range e in which the press roller 17 continues to press the stencil paper 14 may be 10 m+w or more.

Further, as shown in FIG. 4, if projections 26 are formed on both sides of the tip of the first weir 22, the prevention of "liquid leakage" of the ink 10 can be further improved. In this case, according to the experimental results, the width g of the concave portion of the first weir 22 is set by IIl~4ffi than the lif of the support cylinder 2.
■It is necessary to take a certain amount of space.

Next, a third embodiment of the present invention will be described based on FIG. 6. In this case, one of the weirs of the present invention is made by subjecting the terminal end portion 27 of the screen layer 3 to easy processing. The end portion 27 of the screen layer 3 has a thickness of 0.
, 3 ff A first weir 29 and a second term 30 formed on the weir forming member 28 made of an ink-impermeable material of 1 m to 1 mm.
and the contact portions are bonded together with an adhesive 25. Thereby, it is possible to obtain the same "liquid leakage" prevention effect as in the second embodiment.

Next, a fourth embodiment of the present invention will be described based on FIG. 7. In this case as well, the weir according to the present invention is made by easily processing the terminal end 27 of the screen layer 3, as in the third embodiment. That is, the first weir 31 and the second section 32 made of an ink-impermeable material such as filament tape are laminated and pasted on the upper and lower surfaces of the screen layer 3 in several stages. By making this easy attachment by work, it is possible to obtain the same "liquid leakage" prevention effect as in the third embodiment.

Effect Since the present invention forms a dam between the outer peripheral surface of the cylindrical body and the base paper to prevent ink from leaking to the outside, it is possible to prevent "liquid leakage" of ink that occurs from the gap between the screen layer and the base paper. This makes it possible.

It is possible to eliminate contamination inside the device, and since the end of the base paper does not come into close contact with the screen layer, it is possible to eliminate mistakes in plate discharge.

[Brief explanation of the drawing]

FIG. 1 is a vertical side view of a stencil printing device showing the overall configuration of the first embodiment of the present invention, FIG. 2 is a vertical side view showing an enlarged portion of the liquid leakage prevention structure, and FIG. A vertical sectional side view showing the second embodiment of the invention, FIG. 4 is a perspective view of that part,
FIG. 5 is a perspective view of the supporting cylindrical body, FIG. 6 is a longitudinal sectional side view showing a third embodiment of the invention, and FIG. 7 is a longitudinal sectional side view showing a fourth embodiment of the invention. 2... Support cylindrical body (cylindrical body), 3... Screen layer, 4... Opening part, 5... Non-opening part, 6... Ink supply device. 10...Ink, 13...Base paper installation section (relevant section)
, 14... stencil paper (base paper), 17... press roller, 19.22, 23, 29, 30, 31, 32...
Weir (liquid leak prevention device),! F3 Kunbei map 15

Claims (1)

[Claims] A cylindrical body that has an aperture and a non-aperture on its side surface and rotates around its axis; an ink supply device that is provided inside the cylindrical body and supplies ink to the inner circumferential surface of the cylindrical body; ,
a screen layer attached to the outer peripheral surface of the cylindrical body; a base paper whose tip end is locked by a locking part provided in the non-opening part of the cylindrical body and wound around the outer peripheral surface of the screen layer; In a stencil printing device comprising a press roller that presses the base paper wrapped around the outer peripheral surface of the cylindrical body, a dam is formed between the outer peripheral surface of the cylindrical body and the base paper to prevent ink from leaking to the outside. A liquid leakage prevention device for a stencil printing device, characterized by: