JPH0576768U - Gum liquid coating device for photosensitive lithographic printing plate - Google Patents

Abstract

(57) [Abstract] [Purpose] To prevent backflow of gum liquid from the coating roller pair to the conveying roller pair side while maintaining the inclination angle of the coating roller pair substantially the same as the inclination angle of the conveying roller pair. . [Configuration] A gum liquid coating device is a device for coating the photosensitive lithographic printing plate with the gum liquid, and includes a conveying roller pair 3;
A coating roller pair 4, a gum solution homogenizing roller 5 and a gum solution supplying roller 6 are provided. The conveying roller pair 3 is composed of a pair of upper and lower rollers 3a and 3b having a first contact surface C inclined so as to send the printing plate obliquely downward. The coating roller pair 4 is disposed substantially parallel to the first contact surface C and above the first contact surface C so as to send the printing plate sent from the transport roller pair 3 obliquely downward. It is composed of a pair of upper and lower rollers 4a and 4b having two contact surfaces D. The gum solution homogenizing roller 5 and the gum solution supplying roller 6 supply the gum solution to the coating roller pair 4.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a coating device, and more particularly to a gum liquid coating device for coating a photosensitive lithographic printing plate after development with a gum liquid.

[0002]

[Prior art and its problems]

 The image-printed photosensitive lithographic printing plate is continuously processed while being conveyed along a conveying line in an automatic developing device. That is, the photosensitive lithographic printing plate is developed with a developing solution in the developing section, washed with a washing solution in the washing section, and then rinsed with a rinse solution in the rinse section.

Subsequently, the photosensitive lithographic printing plate is supplied to a gum solution coating device and subjected to a gum solution coating treatment. A conveying roller pair, a coating roller pair, and a gum solution supplying means are arranged in the gum solution applying device. The conveying roller pair and the coating roller pair are composed of a pair of upper and lower rollers inclined so as to send the printing plate obliquely downward. Here, the photosensitive lithographic printing plate is sent from the pair of conveying rollers to the pair of coating rollers, and when passing through the pair of coating rollers, the gum solution is coated and desensitized.

Since the printing plate sent from the conveying roller pair to the applying roller pair is sent obliquely downward, a gum solution pool is formed between the printing plate and the upper roller of the applying roller pair. Due to this gum liquid pool, the gum liquid treatment is uniformly applied to the surface of the printing plate. However, in the above-mentioned conventional example, when the trailing edge of the printing plate is sent out from the pair of transport rollers, the weight of the gum liquid pool formed on the printing plate causes the trailing edge of the printing plate to hang down. Sometimes. Then, the gum solution overflows from the printing plate, and the gum solution flows backward and adheres to the side opposite the transport roller.

Therefore, in the gum solution coating device disclosed in Japanese Patent Application Laid-Open No. 2-112430, the inclination angle of the coating roller pair is made larger than the inclination angle of the conveying roller pair. For this reason, when the trailing edge is sent out from the transport roller, the printing plate is further conveyed at a steeper angle and is conveyed downward. Is prevented from flowing backward to the pair of conveying rollers.

However, if the inclination angle of the coating roller pair is increased, the following problems occur. That is, it becomes difficult to return the printing plate after applying the gum solution to the horizontal position when the printing plate is sent to the drying section. Further, there is known a means for separating each roller pair in order to prevent the sticking of the rollers by the gum solution at the end of the work. The means for doing so, that is, the mechanism for lifting up the upper rollers of the plurality of roller pairs becomes complicated.

An object of the present invention is to prevent backflow of gum liquid from the coating roller pair to the conveying roller pair side while maintaining the inclination angle of the coating roller pair substantially the same as the inclination angle of the conveying roller pair. Especially.

[0008]

[Means for Solving the Problems]

 A gum liquid coating device for a photosensitive lithographic printing plate according to the present invention is a gum liquid coating device for coating a photosensitive lithographic printing plate with a gum liquid, and includes a conveying roller pair, a coating roller pair, and a gum liquid supplying device. And means. The transport roller pair is composed of a pair of upper and lower rollers having a first contact surface inclined so as to send the printing plate obliquely downward. The coating roller pair is a second contact surface which is arranged substantially parallel to the first contact surface and above the first contact surface so that the printing plate sent from the transport roller pair is sent obliquely downward. Is composed of a pair of upper and lower rollers. The gum solution supplying means is means for supplying a gum solution to the printing plate passing through the coating roller pair.

[0009]

[Action]

 In the gum solution coating device for the photosensitive lithographic printing plate according to the present invention, the printing plate fed obliquely downward from the conveying roller pair at a predetermined angle is fed to the coating roller pair. Then, when passing through the coating roller pair, a gum liquid reservoir is formed between the upper surface of the printing plate and the coating roller pair, and the gum liquid is applied to the surface of the printing plate.

When the printing plate passes the conveying roller pair, it tries to pass the first contact surface, and when it passes the coating roller pair, it tries to pass the second contact surface arranged above it. Therefore, before the trailing edge of the printing plate comes off the conveying roller pair, the printing plate is bent upward from the first contact surface to the second contact surface. When the trailing edge of the printing plate comes off the conveying roller pair, it jumps up from the first contact surface to the second contact surface. This bouncing action can prevent backflow of the gum solution in the gum solution pool.

Further, here, the respective contact surfaces of the conveying roller pair and the applying roller pair are substantially parallel to each other. That is, the inclination angles of both roller pairs are substantially the same, and there is no problem when the inclination angle of the coating roller pair is made larger than that of the conveying roller pair.

[0012]

【Example】

 FIG. 1 shows a gum solution coating apparatus as an embodiment of the present invention. The gum solution applying device is mainly composed of a gum solution applying section 1 and a drying section 2 arranged at a subsequent stage of the gum solution applying section 1. A table 19 is arranged in front of the gum solution application unit 1. A slit 1a extending in the lateral direction for guiding the printing plate from the table 19 to the gum solution applying section 1 is formed on the front plate of the gum solution applying section 1.

Next, the gum solution applying section 1 will be described. In the vicinity of the slit 1a, a conveying roller pair 3 including a pair of upper and lower rollers 3a and 3b is arranged. A coating roller pair 4 composed of a pair of upper and lower rollers 4a and 4b is arranged behind the transport roller pair 3, that is, on the drying section 2 side. A gum solution homogenizing roller 5 is disposed diagonally above the upper roller 4a of the coating roller pair 4. A gum solution supply pipe 6 is arranged above the upper roller 4a and the gum solution homogenizing roller 5. The gum solution supply pipe 6 is supplied with gum solution from a gum solution tank (not shown) via a pump, and the gum solution is dropped onto the upper roller 4a and the gum solution uniformizing roller 5 through a plurality of holes provided in the lower portion. It is for doing. Each of the above rollers is supported by both side plates (not shown) of the gum solution application section 1 and is connected to a drive source (not shown).

As shown in FIG. 2, the upper roller 3 a and the lower roller 3 b of the transport roller pair 3 are rotatably supported by shaft bearings at their shaft cores. The shaft rollers of the upper roller 4a and the lower roller 4b of the coating roller pair 4 are rotatably supported by bearings 17. In addition, the side plate of the gum solution application unit 1 has a cam formed of a cam hole 18a and a cam pin 18b arranged in the cam hole 18a at a portion corresponding to the lower portions of the upper rollers 3a and 4a of the bearings 16 and 17. The mechanism is in place. The cam pin 18b is connected to a lever mechanism (not shown), and by operating the lever mechanism, it is possible to move inside the cam hole 18a and push up the shaft cores of the upper rollers 3a and 4a.

The upper portions of the bearings 16 and 17 are inclined rearward in the conveying direction (leftward in FIG. 2), and as a result, the conveying roller pair 3 and the application roller pair 4 are also inclined. Here, as shown in FIG. 3, the inclination angles θ of the conveying roller pair 3 and the coating roller pair 4 with respect to the vertical line A are the same. Therefore, the first contact surface C between the upper roller 3a and the lower roller 3b of the conveying roller pair 3 and the second contact surface D between the upper roller 4a and the lower roller 4b of the coating roller pair 4 are formed. And are parallel to. The second contact surface D is arranged at a position higher than the first contact surface C by L.

In the drying unit 2, the flower-shaped rollers 7 and 8, the flower-shaped roller pair 9 including the pair of flower-shaped rollers 9 a and 9 b, and the pair of rollers from the side of the communication port with the gum solution application unit 1. A discharge roller pair 10 including 10a and 10b is arranged in order. Air slits 11 and 12 are vertically arranged between the flower-shaped roller 8 and the flower-shaped roller pair 9. Air slits 13 and 14 are arranged vertically between the flower roller pair 9 and the discharge roller pair 10. Hot air is supplied from the air slits 11 to 14 to dry the photosensitive lithographic printing plate after the gum solution is applied.

Next, the operation will be described. The photosensitive lithographic printing plate, which has been developed, washed with water and rinsed by an automatic developing device, is placed on the table 19 and inserted into the gum solution application section 1 through the slit 1a. The printing plate inserted between the pair of transport rollers 3 is sent out to the coating roller pair 4 side on the first contact surface C which is inclined obliquely downward as shown in FIG. The printing plate inserted between the coating roller pair 4 is sent out obliquely downward along the second contact surface D.

On the other hand, the gum solution dropped from the gum solution supply roller 6 forms a pool between the upper roller 4 a of the coating roller pair 4 and the gum solution uniformizing roller 5 as shown in FIG. .. Then, the gum liquid uniformizing roller 5 is rotated to uniformly supply the gum liquid to the surface of the upper roller 4a. Then, the gum liquid forms a gum liquid reservoir on the upper side of the printing plate (X in FIG. 4) passing between the coating roller pair 4. As a result, the gum solution is uniformly applied over the entire upper surface of the printing plate. Further, the portion of the printing plate X where the gum liquid pool is formed is inclined along the second contact surface D, and the inclination prevents the gum liquid from flowing back to the conveying roller pair 3 side. Further, at this time, since the trailing edge of the printing plate X passes between the conveying roller pair 3, it is along the first contact surface C 1.

When the rear end of the printing plate X is disengaged from the pair of transport rollers 3 from the state shown in FIG. 4, the rear end jumps up to the position of the second contact surface D as shown in FIG. This prevents the gum solution from flowing back due to the trailing edge of the printing plate hanging down. The printing plate after the gum solution is applied is sent from the applying roller pair 4 to the drying unit 2. The printing plate, which is sent out obliquely downward along the second contact surface D, passes through the passage opening between the gum solution application section 1 and the drying section 2 and is conveyed onto the flower-shaped roller 7. At the flower-shaped roller 7, the printing plate is returned horizontally and conveyed. At this time, since the inclination angle of the printing plate sent from the coating roller pair 4 is not large, the printing plate is more easily leveled by the flower-shaped roller 7, and the flower-shaped roller 7 leaves a trace on the printing plate. Unlikely to occur. In the drying section 2, the printing plate is horizontally conveyed by the flower type rollers 7 and 8 and the upper and lower flower type rollers 9. Then, hot air is supplied from the air slits 11, 12, 13 and 14 to perform a drying process. The printing plate after the completion of the drying process is carried out to the outside by the discharge roller pair 10.

After the predetermined gum solution treatment is completed, a lift-up mechanism (not shown) is operated. Then, from the state of FIG. 2, the cam pin 18b moves in the cam hole 18a to the left side of the figure. As a result, the cam 18b pushes up the respective shaft cores of the upper rollers 3a and 4a. As a result, the upper rollers 3a and 4a move upward and separate from the lower rollers 3b and 4b. By the above lift-up operation, it is possible to prevent the upper roller and the lower roller from being fixed by the gum solution. In this embodiment, since the conveying roller pair 3 and the coating roller pair 4 have the same inclination angle, the structure for lifting the two in cooperation with each other is simple.

[Other Embodiments] In the above embodiments, the present invention is applied to the gum solution coating device independent of the automatic developing device. However, the present invention may be applied to the gum liquid coating device integrated into the automatic developing device. Good.

[0022]

[Effect of the device]

 In the gum solution coating device for the photosensitive lithographic printing plate according to the present invention, the second contact surface of the coating roller pair is disposed substantially parallel to and above the first contact surface of the transport roller pair. Therefore, it is possible to prevent the gum solution from flowing back to the conveying roller pair side while maintaining the inclination angle of the coating roller pair substantially the same as the inclination angle of the conveying roller pair.

[Brief description of drawings]

FIG. 1 is a schematic vertical cross-sectional view of a gum solution coating device as one embodiment of the present invention.

FIG. 2 is an enlarged partial view of FIG.

FIG. 3 is a schematic vertical cross-sectional view showing an inclined state of a conveyance roller pair and a coating roller pair.

FIG. 4 is a view corresponding to FIG. 3 showing a printing plate passing state.

FIG. 5 is a view corresponding to FIG. 3 showing another passing state.

[Explanation of symbols]

 1 Gum Liquid Coating Section 3 Conveying Roller Pair 4 Coating Roller Pair 5 Gum Liquid Uniformizing Roller 6 Gum Liquid Supply Pipe C 1st Contact Surface D 2nd Contact Surface

Claims (1)

[Scope of utility model registration request] 1. A gum solution applying device for applying a gum solution to a photosensitive lithographic printing plate, comprising a pair of upper and lower rollers having a first contact surface inclined so as to send the printing plate obliquely downward. And a pair of transport rollers that are arranged substantially parallel to the first contact surface and above the first contact surface so that the printing plate sent from the transport roller pair is sent obliquely downward. A photosensitive lithographic printing plate comprising: a coating roller pair including a pair of upper and lower rollers having a second contact surface; and a gum liquid supply means for supplying a gum liquid to the printing plate passing through the coating roller pair. Gum liquid application device.