JPH0730358Y2 - Lithographic printing plate mounting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Industrial field of application The present invention is a planographic printing machine, in which a flexible substrate having a surface that retains water against dampening water is coated and fixed on the plate cylinder surface of the plate. The present invention relates to a lithographic printing plate mounting apparatus which can be applied to a printing method in which a lithographic printing plate (also simply referred to as a “printing plate”) is fixed on the top of the plate to obtain a printed matter free from ink stains regardless of the size of the printing plate.

(B) Prior art and its problems Lithographic printing is performed by mounting a lithographic printing plate on the surface of a plate cylinder called a master cylinder, and supplying oil-based ink and fountain solution to the mounted plate surface. In this case, the ink is received by the lipophilic print image on the plate surface and the dampening water is received by the water-retaining non-image area, resulting in ink repulsion, and the ink receptivity of the plate surface and ink repulsion are well balanced. This enables lithographic printing.

Printing machines used for such lithographic printing are of various sizes having different printing areas, from large-scale printing machines used for newspaper printing to small desktop printing machines. The size of the plate cylinder of these printing machines is fixed according to the printing model,
The size of the printing plate that can be printed by one type of printing machine is determined for each printing machine. Therefore, when printing with printing plates of various sizes, it is conceivable to prepare printing machines of various sizes, but enormous equipment costs and installation space are required. Prepare and print one large size and one small size. In this case, even if the printed matter has a small size, it is necessary to use a large size printing plate, and there is a problem that the printing plate is wasted.

As a method of solving these problems, the entire printing effective surface of the plate cylinder surface of a large-sized printing press is covered with a flexible substrate having a surface that is water-retentive to the fountain solution that has been grained. By fixing and fixing a printing plate with an area smaller than the total printing effective area of the plate cylinder, which is aligned on this water retentive surface, with an adhesive, it is fixed so that ink stains on the outside of the printing plate. No. 60-38740 proposes a method capable of printing without causing a print.

This method covers and fixes a substrate having a water retentive surface to the plate cylinder surface by both the bite and bite butt clamps of the plate cylinder,
A plurality of positioning pins are held in the bite clamp, and a plurality of pin holes formed at positions corresponding to the positions of the positioning pins at the bite side end of the plate are used for the positioning pins. The position of the printing plate is adjusted by hooking on.

However, in this method, as described in the above publication, the pin holes of the printing plate are usually formed in a circular shape by punching, whereas the positioning pins are formed in a flat plate-like body. Therefore, when the plate is hooked on the pin, the engagement position between the pin and the pin hole is displaced, or when the plate is a paper plate whose base is paper, the pin hole of the plate is broken and the positional accuracy is There is a problem that it becomes worse and causes a defective printed matter. Also, since it is necessary to repeat careful work to prevent these problems, it takes a long time to mount the plate,
There is a problem of reducing workability.

(C) Purpose of the Invention The purpose of the present invention is to provide a lithographic printing plate mounting device which eliminates the above-mentioned drawbacks and has good position accuracy and workability at the time of plate mounting, and which makes it possible to obtain good quality printed matter. is there.

(D) Configuration of the Invention Based on the finding that the object of the present invention is achieved by making the shape of the alignment pin the same shape as the pin hole of the printing plate and in a close engagement relationship, this should be realized. The inventors have devised the following plate mounting device.

That is, according to the present invention, a flexible substrate having a surface that retains water against dampening water is coated and fixed on the plate cylinder surface of a lithographic printing machine by both the bite and bite butt clamps of the plate cylinder. In addition, a pin for aligning the plate is installed on the bite, and a pin hole formed in advance on the bite side end of the plate is hung on the pin to attach the plate to the plate cylinder. A device, comprising: a first pin bar having at least two plate alignment pins serving as the alignment pins and having a mechanism that can be detachably fixed to the bite; A second pin bar having a pin hole that engages with the positioning pin of the first pin bar and a pin that can fix the position of the printing plate when mounted on the plate cylinder; Biting the plate cylinder with the second pin bar engaged with the first pin bar That is configured to secure to the side is a lithographic printing plate of the mounting device according to claim.

(E) Embodiment An embodiment of the present invention will be described below with reference to the drawings.
The present invention is not limited to this.

FIG. 1 is a perspective view showing a first pin bar (positioning pin bar) of the present invention, and FIGS. 1 (A) and 1 (B) show the same thing viewed from both front and back sides. It shows the state.

FIG. 2 is a perspective view showing a second pin bar (pin plate fixing pin bar) of the present invention.

The first pin bar 1 is provided with two cylindrical printing plate positioning pins 3 on a base body 2, and fixing screws 4 and 5 to the plate cylinder are provided.
2 and 6 are provided for each. Two screws 4 are used for fixing in the width direction, and two screws 5 are used for adjusting the height. The two screws 6 are used for fixing in the front-rear direction together with the four springs 10 (see FIGS. 3 and 6) which are fitted into the four spring insertion holes 7. Magnets 9 are fitted in the five magnet fitting holes 8, and the positions of these holes coincide with the positions of the five plate fixing pins 13 of the second pin bar 11 when the plate is mounted. (See FIG. 8).

The second pin bar 11 has a base 12 provided with five cylindrical plate fixing pins 13 and two circular pin holes 14. The positions of the five pins 13 and the two pin holes 14 should correspond to the five fitting holes 8 and the magnet 9 of the pin bar 1 and the two positioning pins 3 when the plate is mounted. It is set (see FIG. 8).

Next, a specific usage mode of the mounting device of the present invention will be described with reference to the drawings.

A pair of stainless steel pin bars shown in FIGS. 1 and 2 were manufactured. The main specifications are as follows.

First pin bar 1; base 2 thickness 8 mm, front and rear width 8 mm, widthwise length 650 mm, pin 3 diameter 6 mm, height 4 mm Second pin bar 11; base 12 thickness 2.5 mm, front and rear width 8 mm, Width length 650 mm, pin 13 diameter 6 mm, height 1 mm, pin hole 14
First, the first pin bar 1 is fixed between the clamp 22 of the plate cylinder 21 and the plate cylinder surface 23 as shown in FIGS. 3 and 6. FIG. 3 is a plan view showing a state in which the first pin bar of the present invention is fixed to the plate body bite, and FIG. 6 is a side sectional view (partial side view) of the plate body bite and bite butt. is there. 2 fixing screws 4
Then, it is fixed to the inner wall surfaces of the left and right bearers 24, and is fixed to the inner wall surface of the plate cylinder surface 23 and the inner wall surface of the clamp 22 with two fixing screws 6 and four springs 10. The height is adjusted in advance by the two screws 5 as shown in FIG. 6 before fixing the pin bar 1.

Next, as shown in FIGS. 4 and 6, a flexible aluminum plate 30 having a water-retentive surface 31 having a grained surface is wound around the entire surface of the plate cylinder surface 23. Clamp end 22 and clamp end 25
To hold and tighten to cover and fix. At this time, the end of the aluminum plate 30 on the bite side avoids the pin 3 of the pin bar 1, so that it coincides with the position of the pin 3 as shown in FIG.
A cutout 32 is provided at the location. The notch 32 may be a punched pin hole. FIG. 4 is a perspective view of the plate cylinder biting side, and FIG. 6 is a partial side sectional view (partial side view) of the plate cylinder showing the usage state of the present invention.

FIG. 5 is a perspective view showing a state in which the plate is attached to the plate fixing pin bar of the present invention, FIG. 5 (A) is the back side of the plate, and FIG. 5 (B) is the plate surface (printing). It is a perspective view of the (image surface) side. Multiple (7 in the figure) circular pin holes 43 on the bite side end
With the surface 42 of the punched plate 40 and the pin bar 11 facing each other, as shown in FIG.
The individual pins 13 and the pin holes 43 of the printing plate are engaged with each other to fix the printing plate 40 to the pin bar 11, and the front and back of the plate 40 are reversed as shown in FIG. 5 (B). The two pins 3 in the state and the two pin holes 43 of the printing plate 40 are engaged with the two pin holes 14 of the pin bar 11 which overlap with each other to form the pin holes, and the printing plate
The entire surface of the back surface 41 of 40 is adhered to the surface 31 of the grained aluminum plate 30 via an adhesive, and the printing plate 40 is fixed so as not to move so that printing can be performed. .

In this case, the printing plate 40 is fixed to the surface 31 of the aluminum plate 30 which is covered and fixed to the plate body surface 23 with an adhesive.
Since it is not necessary for the clamp 25 to grip the bite end of the plate, printing can be performed even with a printing plate smaller than the plate cylinder surface as shown in FIG. FIG. 7 is a side sectional view showing the usage state of the device of the present invention.

FIG. 8 is a vertical cross-sectional view (however, the fixing mechanism is omitted) in the width direction of the device of the present invention in use. The plate 40 laminated on the surface of the aluminum plate 30 has two pin holes 43 fixed together with the pin holes 14 of the second pin bar 11 by the two pins 3 of the first pin bar 1. And the remaining five pin holes 43 of the printing plate 40 are aligned with the second pin bar 11.
It is fixed by 5 pins 13 of. Moreover, since the magnets 9 are embedded in the first pin bar 1 at the positions of the five pins 13 of the second pin bar 11, the two pin bars are attracted by the magnetic force, and the second pin bar is attracted. 11 does not come off during printing. The strength of this magnet is strong, for example, the residual magnetic flux density (Br) is about 1500 Gaus.
Those having a strength of s or more are preferable. As a method of preventing the second pin bar 11 from coming off during printing, for example, a method of sandwiching the two pin bars 1 and 11 from the top and bottom at both ends in the width direction with “U” shaped metal fittings can be considered. It is preferable to use a magnet because the work of pinching is troublesome and may be dropped during the work, or may come off during printing.

In the use of the device of the present invention, in order to improve the adhesion between the water-retaining substrate 30 and the first pin bar 1 and between the printing plate 40 and the second pin bar 11, the respective contact surfaces are detachably attached with an adhesive. Good. Adhesion of these improves not only the adherence of the printing plate to the plate cylinder during printing but also the printing accuracy.

There are various flexible substrates having a surface that retains water against dampening water used in the present invention.
It can be obtained as a support of a lithographic printing plate called a so-called PS plate, or can be obtained by etching the commercially available PS plate with a developing solution to remove the photosensitive layer on the support. An adhesive for removably attaching and fixing a printing plate on the water-retaining surface can be obtained, for example, under the trade name Design Bond manufactured by US 3M Company.

(F) Effect of the Invention According to the present invention, the alignment pin having the same shape as the pin hole of the punched printing plate can be fixedly installed on the bite of the plate cylinder, and the engagement between the pin and the pin hole during printing can be achieved. The alignment position does not shift, and the pin hole does not break even with a paper plate, so that the positional accuracy is improved and a high-quality printed matter can be produced.

Further, in the device of the present invention, if the plate is attached to the second pin bar in advance, it is very easy to attach the plate to the alignment pin of the first pin bar, and the careful work as in the past is not necessary. It becomes unnecessary and the workability is improved. Therefore, if a plurality of second pin bars are prepared, the second plate of the next printing plate being printed is printed.
Since it can be attached to the pin bar, the time required for plate mounting is greatly reduced when a large number of printing plates are continuously printed.

[Brief description of drawings]

1 (A), (B) and FIG. 2 are perspective views showing an example of the constitutional body of the device of the present invention, and FIGS. 3, 4 and 5 (A), (B) are the present invention. FIG. 6 is a plan view and a perspective view showing an application procedure of the apparatus of FIG. 1 to a plate cylinder, and FIGS. 6 and 7 are partial sectional views and whole sectional views showing a state in which a plate is mounted on the plate cylinder by the apparatus of the present invention. FIG. 8 is a longitudinal sectional view in the width direction showing a state in which the printing plate is mounted on the plate cylinder by the device of the present invention. 1 ... Alignment pin bar (first pin bar) 3 ... Alignment pin 4,5 and 6 ... Pin bar fixing screw 7 ... Spring fitting hole 8 ... Magnet fitting hole 9 ... Magnet 10 ... Spring 11 ... Plate fixing Pin bar (second pin bar) 13 ... Plate fixing pin 14 ... Pin hole 21 ... Plate cylinder 22 and 25 ... Clamp 23 ... Plate cylinder surface 24 ... Bearer 30 ... Flexible substrate having water retentive surface 40 ... Plate 43 ... Pin hole

Claims (2)

[Scope of utility model registration request] 1. A flexible substrate having a surface that retains water against dampening water is fixed to the plate cylinder surface of a lithographic printing machine by both clamps of the bite and bite tail of the plate cylinder. A device for mounting a plate alignment pin on the bite, mounting a pin hole previously formed on the bite side end of the plate on the pin, and mounting the plate on the plate cylinder. And a first pin bar having at least two plate alignment pins that serve as the alignment pins and having a mechanism that can be detachably fixed to the bite, and the plate of the plate A second pin bar having a pin hole that engages with the positioning pin of the first pin bar and a pin that can fix the position of the printing plate when mounted on the cylinder; Biting the plate cylinder with the second pin bar engaged with the second pin bar The lithographic printing plate mounting apparatus characterized by being configured to secure the. 2. The lithographic printing plate mounting apparatus according to claim 1, wherein the fixing means is a magnet.