JPH0734423Y2 - Exhaust device for vacuum contact printer - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a vacuum contact printer for printing exposure by adhering an original plate and a photosensitive material by a vacuum pressure in a photo reproduction work such as photoengraving. Regarding exhaust system.

[Conventional technology]

FIG. 4 is a schematic diagram showing the configuration of an example of a conventional vacuum contact printer.

A light-transmitting plate (3) such as glass is mounted on the upper surface of a frame (1) provided with a light source (2) for exposure inside, and a peripheral portion of the light-transmitting plate (3) is made of rubber or the like. The packing strips (4) are glued upright.

An airtight sheet (5) is spread on the upper surface of the translucent plate (3), and a vacuum pump (not shown) is used to open an exhaust portion (6) that opens at one corner on the rear edge side (right end in the figure) of the translucent plate (3). ) Via
By removing the air between the transparent plate (3) and the airtight sheet (5) and bringing the airtight sheet (5) into close contact with the transparent plate (3) by atmospheric pressure, the transparent plate (3) The original plate placed on top of it and the photosensitive material are brought into close contact with each other, and the light source (2) is turned on to perform printing exposure.

The front end edge of the airtight sheet (5) is fixed to the front edge portion of the frame (1), and the rear end is wound around the winding roller (7) with a spring. By rolling the take-up roller (7) backward, the airtight sheet (5) is stretched on the transparent plate (3) and is moved backward by the squeegee roller (8) together with the take-up roller (7). , The air between the airtight sheet (5) and the translucent plate (3) is wicked off,
The time required for evacuation is shortened.

When the airtight sheet (5) is wound up, the winding roller (7) and the squeegee roller (8) are provided with a stepped portion formed at the front edge of the frame (1) for the convenience of attaching and detaching the original plate and the photosensitive material. It is submerged and stored in (9).

FIG. 5 is a perspective view showing the structure of the exhaust part (6) in the above-mentioned conventional device, and an exhaust metal fitting (10) having a flange at the upper end in a through hole provided in a key part of the translucent plate (3). Insert the hose (12) and fix it with the nut (11) on the bottom side.
Is connected to a vacuum pump.

[Problems to be solved by the device]

In the conventional device as shown in FIG. 4 and FIG. 5, since the exhaust metal fitting (10) is projected on the upper surface of the translucent plate (3), when the original plate or the photosensitive material is loaded, this part Therefore, the area applicable to the baking exposure (hereinafter referred to as the effective area) becomes smaller than the range that is actually vacuum-bonded, that is, the range surrounded by the packing strips (4).

Further, in the above-mentioned conventional device, since the exhaust part (6) is provided on the trailing edge side of the translucent plate (3), when the airtight sheet (5) is stretched from the leading edge side to the trailing edge side, it is wound up. Evacuation is not performed until the roller (7) reaches the position of the exhaust unit (6), and it takes a long time to reach the required close contact state.

In order to improve this, the accommodating portion (9) of the airtight sheet (5) may be on the trailing edge side, but doing so has a problem in actual work.

That is, at the time of contact printing, a pin-and-bar in which a pair of register pins are erected to fit a punch bar punched in a film that is the original plate and the photosensitive material for positioning the superposition of the original plate and the photosensitive material. When the punch system is applied, to attach and detach the original plate and the photosensitive material,
It is necessary to install the pin bar on the front edge side of the light-transmitting plate (3), and in order to prevent the film from sagging and misaligning when the airtight sheet is expanded, the expansion roller (7) is attached to the pin bar. From the mounted side to the other end,
It has to be rolled, and the accommodating part (9) of the airtight sheet (5) must necessarily be arranged on the front edge side.

On the other hand, installing the exhaust section (6) on the front edge side has another problem. That is, in the illustrated device, the transparent plate (3)
For the convenience of cleaning the lower surface of the, the rear edge of the transparent plate (3) is hinged to the frame (1), and when cleaning, open upward as shown by the chain line in FIG. However, if the exhaust part (6) is located on the front edge side, the rubber hose (12) connected to the exhaust part (6) hangs down from the front edge part of the opened translucent plate (3), which disturbs the work. become. Therefore, it is necessary to remove the rubber hose (12) each time when cleaning, which is troublesome.

The present invention reasonably solves these problems.

[Means for Solving the Problems]

According to the present invention, the above problem is solved as follows.

(1) On a top surface of a frame having a built-in light source for exposure, a light-transmitting plate having a packing strip standing on the peripheral edge is hinged so that it can be opened and closed.
In a vacuum contact printer in which an airtight sheet is spread on the upper surface of the translucent plate and the space between the translucent plate and the airtight sheet is evacuated and brought into close contact, the hinge part for the frame of the translucent plate is attached to the rear part of the frame. The front end of the airtight sheet is fastened to the front part of the frame, and the rear end of the airtight sheet is wound around the take-up roller. The air intake pipe is provided through the hole, has an opening end facing upward in the frame located directly below the through hole, and an intake pipe is installed at this opening end at a required distance from the lower surface of the light transmitting plate. A cushion cylinder made of an elastic material is fitted to the open end of the transparent material so that the upper end of the transparent material comes into contact with the periphery of the through hole of the transparent plate and is airtightly pressed when the upper surface of the frame is closed.

(2) In the preceding paragraph, a plurality of the through holes are provided in the light transmitting plate, and the intake pipes fitted with the cushion cylinders are arranged directly below the respective through holes.

(3) In any one of the preceding 2 paragraphs, the longitudinal cross-sectional shape of the packing strip that is erected on the peripheral portion of the light-transmitting plate is such that the upper edge portion against which the airtight sheet abuts is inwardly extended, and The through hole for exhaust is arranged below the portion.

[Action]

According to the first aspect of the present invention, in a state in which the upper surface of the frame is covered with the translucent plate, the upper end of the cushion tubular body fitted to the intake pipe is in contact with the periphery of the transmissive hole on the lower surface of the translucent plate to provide an airtight seal. Since it is pressure-bonded to, it is possible to reliably exhaust air through the through hole of the light transmitting plate.

Further, since the cushion tubular body is only pressure-bonded to the transparent plate, it can be separated, and only the transparent plate can be opened upward at the time of cleaning or the like.

According to the second aspect of the present invention, the amount of exhaust gas is increased by increasing the number of through holes provided in the translucent plate and the number of exhaust pipes provided with the cushion tubular body until the required close contact state is reached. The time can be shortened.

In the invention of claim 3, the longitudinal section of the packing strip is
By forming the shape in which the upper edge portion bulges inward, when the packing strip is pressed and deformed by the airtight sheet during vacuum evacuation, an air passage is formed under the bulging portion, and By arranging the through hole below the projecting portion, exhaust is performed from the entire circumference of the translucent plate, local air bubbles are prevented from remaining locally, and the exhaust can be efficiently performed.

〔Example〕

FIG. 1 is a cutaway perspective view showing a front edge portion of a vacuum contact printer according to an embodiment of the present invention.

The structure and arrangement of the entire frame, the airtight sheet and the winding roller thereof are the same as those of the conventional apparatus shown in FIG. Therefore, their illustration and description are omitted.

A transparent plate (21) made of glass or the like is attached to the upper surface of a rectangular support frame (22) formed of a rod having a U-shaped vertical section through a mounting member (23). The rear edge of the support frame (22) is hinged to the upper rear edge of the frame (26) so that it can be opened upward for cleaning or the like.

A packing strip (24) made of an elastic material such as rubber and having an upper edge protruding inward and having an inverted L-shaped vertical section is fixed to the peripheral edge of the upper surface of the translucent plate (21).

An exhaust hole (25) for exhaust is provided immediately below the overhanging portion (24a) of the packing strip (24) at the front edge of the transparent plate (21).

A supporting plate (27) that projects inward is provided on the upper portion of the front edge of the frame (26), and a through hole (2) is formed on the upper surface of the supporting plate (27).
An intake pipe (28) is attached at a position aligned with the position just below (5).

The upper part of the intake pipe (28) has a small diameter through a step,
Moreover, the lower part is inserted into the support plate (27) and fixed by a nut (29), and is connected to a vacuum pump through an appropriate pipe (30).

At the upper part of the intake pipe (28), the cushion cylinder (3
1) is fitted. The cushion tubular body (31) is made of an elastic material such as rubber, has a bellows shape with a bent portion in the middle, and has an upper end as shown in the cross section of FIG. 2 (A).
It has a suction cup shape that expands outward.

The height of the cushion tubular body (31) is an appropriate compression amount (ΔL) from the natural state shown in FIG. 2 (B) when the upper surface of the frame (26) is closed by the translucent plate (21). The distance between the translucent plate (21) and the support plate (27), the intake pipe (28) so as to be compressed.
It is determined in consideration of the dimensions of. The amount of compression (ΔL) is determined so that a pressure force sufficient to prevent outside air from leaking between the cushion tube body (31) and the translucent plate (21) during vacuum evacuation can be obtained. is there.

Thus, when the upper surface of the frame (26) is closed by the translucent plate (21), the height of the cushion tubular body (31) is (ΔL).
Is compressed, and the cushion cylinder (3
The upper end of 1) is pressure-bonded to the lower surface of the transparent plate (21) to ensure airtightness. Therefore, the air between the translucent plate (21) and the airtight sheet stretched on the upper surface of the translucent plate can be exhausted in the same manner as when the conventional exhaust metal fitting is fixed to the translucent plate.

Particularly, in the present invention, the airtight sheet (5) is stretched rearward, and the exhaust part is attached to the transparent plate (2).
Since it is installed on the front edge side of 1), the air-tight sheet (5) has an evacuation action from the initial stage of expansion, and the time required to obtain the required adhesion state is greatly shortened. According to the experiment, it was confirmed that the time required to reach the required vacuum degree was shortened by about 35 to 40% as compared with the conventional apparatus shown in FIG.

Furthermore, in this case, as the degree of vacuum increases,
Since the airtight sheet (5) adheres to the outer surface of the packing strip (24), if the cross section of the packing strip (4) is, for example, "kamaboko", it simply protrudes above the upper surface of the translucent plate (3). In such a case, the air passage is gradually narrowed, the exhaust efficiency is lowered, and it takes a long time to reach the required degree of adhesion.

However, since the packing strip (24) of the present embodiment has an inverted L-shaped cross-sectional shape with the upper end protruding inward, even when the protruding portion (24a) is pressed downward, Even when a space is formed and an air passage is secured over the entire circumference and the degree of close contact is increased, the air is exhausted from the entire peripheral edge, so that the exhaust efficiency is extremely good.

Further, in the exhaust device of the present invention, there is no member projecting on the upper surface of the translucent plate (21), and the through hole (25) for exhaust is provided in the lower portion of the overhanging portion (24a) of the packing strip (24). Since it is provided, the entire inner surface of the packing strip (24) can be used as an effective exposure area, and higher usage efficiency can be obtained as compared with the conventional vacuum contact printer.

Further, for cleaning the transparent plate (21), etc., the holding frame (22)
To open the above parts from to, the cushion cylinder (31)
The following parts are separated from the translucent plate (21) and remain at the installation location on the frame (26) side, so even if the exhaust part is provided on the front edge side of the translucent plate (21), it is opened. An exhaust hose or the like does not hang down on the lower surface of the translucent plate (21), which does not hinder the cleaning work.

The exhaust device is not limited to one set, and a plurality of sets of devices may be installed in parallel with the front edge of the vacuum contact printer.

FIG. 3 is a schematic view showing a state in which two sets of exhaust devices are installed, and a pair of exhaust holes (25) (25) (25) (25) (25) (25 ), And a pair of intake pipes (28) and (28) are attached to the supporting plate (27) on the frame side at positions aligned with the corresponding through holes (25). As in the above-mentioned embodiment, the cushion tube body (31) is fitted to the upper end of each intake pipe (28) and each intake pipe (28).
The pipe (30) connected to is connected to a vacuum pump by a common pipe line (32).

In the apparatus shown in FIG. 3, since the air is sucked from the two through holes (25) at the time of vacuum evacuation, it is possible to further reduce the time until the required adhesion is increased by increasing the exhaust amount.

Although FIG. 3 shows an example in which two sets of exhaust devices are provided together, it goes without saying that it is also possible to provide three or more sets of exhaust devices together. Absent.

In the conventional vacuum contact printer in which the metal fitting for exhaust is projected on the surface of the translucent plate, if the number of sets of the exhaust device is increased, the effective exposure area is reduced according to the number of sets, and the use efficiency is lowered. Although there was a problem, in the apparatus of the present invention, since the effective exposure area is not reduced by the exhaust device as described above, it is possible to provide a large number of sets of exhaust devices without increasing the size of the apparatus. become.

[Effect of device]

(1) In the invention of claim 1, when the light transmissive plate is opened upward with the rear portion of the frame as a fulcrum, the intake hose is separated from the light transmissive plate, so that the cleaning operation is facilitated.

Further, when the upper surface of the frame is closed by the light-transmitting plate, the upper end of the cushion tube body fitted in the intake pipe abuts the periphery of the through-hole on the lower surface of the light-transmitting plate and is pressure-tightly bonded. Exhaust can be reliably performed through the through holes of the light plate.

Furthermore, since there is no member projecting on the upper surface of the transparent plate, and the entire inner side of the packing strip at the peripheral edge of the transparent plate can be applied as the effective area for printing exposure, the use efficiency of the printer is improved.

(2) In the invention of claim 2, since the exhaust portion is provided on the opening side of the translucent plate, that is, the expansion start side of the airtight sheet, the exhaust can be quickly performed, and the work efficiency is significantly improved.

(3) In the invention of claim 3, a plurality of sets of exhaust devices can be provided side by side without inviting an increase in the size of the device, and the exhaust time can be further shortened to speed up the work.

[Brief description of drawings]

FIG. 1 is a cutaway perspective view showing an essential part of an embodiment of the present invention, FIG. 2 (A) is a sectional view of an exhaust device, and FIG. 2 (B) is a cushion cylinder in a natural state. FIG. 3 is an external view, FIG. 3 is a schematic diagram showing an embodiment to which two sets of exhaust devices are applied, FIG. 4 is a schematic configuration diagram of a conventional vacuum contact printer, and FIG. It is a perspective view. (1) …… Frame (2) …… Light source (3) …… Transparent plate (4) …… Packing strip (5) …… Airtight sheet (6) …… Exhaust section (7) …… Winding roller ( 8) Squeegee roller (10) Exhaust fitting (11) Nut (12) Hose (21) Translucent plate (22) Support frame (24) Packing strip (25) …… Through hole (26) …… Frame (27) …… Overhanging part (28) …… Intake pipe (29) …… Nut (30) (32) …… Exhaust pipe (31) …… Cushion cylinder

Claims (3)

[Scope of utility model registration request] 1. An upper surface of a frame containing a light source for exposure,
A translucent plate with a packing strip standing upright on the periphery is hinged so that it can be opened and closed, and an airtight sheet is spread on the upper surface of the translucent plate so that the space between the translucent plate and the airtight sheet can be exhausted and brought into close contact. In the vacuum contact printer, the hinge part of the translucent plate to the frame is the rear part of the frame, the front end of the airtight sheet is attached to the front part of the frame, and the rear end of the airtight sheet is wound around the take-up roller. The front side of the frame, which is the opening side of the translucent plate, is provided with a through hole for exhaust passing therethrough, and the frame has an opening end facing upward and is located directly below the through hole. An air intake pipe is attached to the open end with a required distance from the lower surface, and the upper end of the air intake plate contacts the periphery of the transparent hole of the light transmissive plate when the upper surface of the frame is closed at the open end of the intake pipe. Cushion cylinder made of elastic material that is airtightly attached An exhaust device for a vacuum contact printer, which is characterized in that 2. The vacuum contact printer according to claim 1, wherein a plurality of through holes are provided in the light transmitting plate, and an intake pipe fitted with a cushion tubular body is arranged immediately below each of the through holes. Exhaust system in. 3. A vertical cross-sectional shape of a packing strip that is erected on the peripheral portion of the light-transmitting plate is such that an upper edge portion against which the airtight sheet abuts extends inward, and below the overhang portion, The exhaust device in a vacuum contact printer according to claim 1, wherein a through hole for exhaust is arranged.