JPH068403A - Press plate positioning apparatus - Google Patents

Abstract

PURPOSE:To improve accuracy in mounting and enable repeated use of a press plate by providing a form plate guiding table held in an inclined manner and adapted to move in an inclined direction and table positioning pins provided on a gripping vise on a plate cylinder and adapted to engage with a lower end of a guiding table. CONSTITUTION:A form plate guiding table 25 is mounted in an inclined manner on a top of a printing unit and is supported by four rollers 24 which roll on guide rails 23 secured to a movable frame. An air cylinder 27 is mounted to a bracket 26 secured to moving rails so as to make the form plate guiding table 25 tiltable in its inclined plane. Two form plate positioning pins 28 are provided on the form plate guiding table 25, and two positioning guides 29 and 30 are provided on a front end 25a of the form plate guiding table 25. After a press plate 9 is positioned and placed on the form plate guiding table 25 by means of U-shaped grooves 9a and the form plate positioning pins 28, it is moved toward a plate cylinder 2 by the air cylinder 27, and the positioning guides 29 and 30 of the form plate guiding table 25 are positioned by pins 31 and 32 which are provided on the plate cylinder. In this position, an upper jaw of a gripping vise 12 is closed to fix the press plate 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plate positioning device for a plate cylinder in an automatic plate changing device of a sheet-fed printing press.

[0002]

2. Description of the Related Art FIG. 3 shows a plate mounting apparatus provided in the automatic plate mounting apparatus described in Japanese Patent Application No. 61-064890. A plate positioning pin 15 is tiltably attached to the lower end portion 1a of the plate guide table 1 held in a tilted manner, and a U-shape that engages with the plate positioning pin 15 at the lower end edge 9a of the printing plate 9 placed on the plate guide table 1. A groove 9b is provided, and a plate positioning pin 16 that engages with the U-shaped groove 9b of the printing plate is planted in the vise side vise 12 of the plate cylinder 2.

The guide table 1 is moved by a proximity device (not shown), and the plate positioning pin 15 is tilted at a position close to the vise side vise 12 of the plate cylinder 2 (area A surrounded by a chain line). As shown in FIG. 4, the printing plate 9 is slid down on the plate guide table 1 by its own weight, and the U-shaped groove 9b of the printing plate is engaged with the plate positioning pin 16 of the gripping side vise 12 to make the printing plate. 9
Is positioned on the plate cylinder 2. After this positioning, the lower edge 9a of the printing plate is closed and grasped by the vise side vise 12.

[0004]

The above-mentioned prior art has the following problems. In FIG. 4, the U-shaped groove 9b of the printing plate 9 is made to slide down by its own weight from a position close to the vise side vise 12 and directly applied to the plate positioning pin 16 of the plate cylinder 2.
The R portion of the mold groove 9b is deformed.

Due to this deformation, an error in mounting the printing plate 9 on the plate cylinder 2 occurs, causing misregistration and deteriorating the printing quality. Further, the printing plate 9 in which the R portion of the U-shaped groove 9b is deformed cannot be reused. In addition, when printing with the plate attached, the left and right registration (movement in the axial direction of the plate cylinder) is adjusted in relation to the printing accuracy, and when the next plate is attached, the left and right registration is set as the original (original It is necessary to return to the state) (because the position of the table 1 and the plate cylinder 2 is not aligned).

SUMMARY OF THE INVENTION It is an object of the present invention to provide a printing plate positioning apparatus for a printing drum which does not have a fear of deforming the U-shaped groove of the printing plate and which does not require a return-to-origin for moving the printing drum in the axial direction. It is what

[0007]

[Means for Solving the Problems]

(1) The positioning guides provided on both side end surfaces of the plate guide table are applied to the reference pins of the plate cylinder, one of the surfaces where the positioning guides contact the reference pins is provided with an inverted V-shaped R groove, and the other positioning guide tip surface is It is on the same line as the bottom of the R groove and parallel to the tangent of the double-end plate positioning pin. (2) The plate guide table is allowed to move freely in a plane where the table is inclined.

[0008]

[Action]

(1) Since the positioning guide with the groove provided on the end face of the plate guide table hits the reference pin of the plate cylinder for positioning, the U-shaped groove of the plate is used only for positioning the plate and the plate guide table, and the U-shaped groove is used. No groove deformation occurs. (2) Since the plate guide table is a guide surface that can freely tilt within an inclined plane, the inverted V-shaped R of one grooved positioning guide is used.
When the V surface of the groove hits one of the plate cylinder reference pins, the plate guide table is guided in the reverse V shape and moves in the axial direction of the plate cylinder, and the plane of the other guide is used as the reference for the other plate cylinder. Since the plate guide table is applied to the pin, the plate guide table is smoothly positioned along the reference pin of the plate cylinder regardless of the axial displacement of the plate cylinder. (3) Therefore, by positioning the plate guide table on the plate cylinder, the printing plate can be positioned on the plate cylinder. In other words, the plate is not positioned directly on the plate cylinder, but the plate is positioned relative to the plate guide table, which is positioned relative to the plate cylinder.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a plate positioning device for a plate cylinder according to the present invention will be described with reference to FIGS. The plate positioning device 21 for the plate cylinder (hereinafter referred to as the plate positioning device) is attached to the upper portion of the printing unit in a tilted manner, and is part of a plate replacement device 13 '(hereinafter referred to as a replacement cassette) that moves in the tilting direction. And the moving frame 22 of the exchange cassette 13 '.
Four rollers 2 rolling on a guide rail 23 fixed to the
4, the plate guide table 25 supported by 4 and the moving rail 2
An air cylinder 27 is attached to a bracket 26 fixed to the plate 2 so that a plate guide table 25 can be freely tilted within its inclined surface, two plate positioning pins 28 provided on the plate guide table 25, and a plate. Front end 25 of the guide table 25
It is composed of two positioning guides 29 and 30 provided on a.

The two plate positioning pins 28 are U-shaped of the printing plate 9.
The plate 9 is positioned with respect to the plate guide table 25 by engaging with the character-shaped groove 9a. Reverse V for the grooved positioning guide 29
An R-shaped groove 29a is provided, the guide 30 is provided with a surface 30a parallel to the tangent line 28a of the double-end plate positioning pin 28, and the line 30b is parallel to the line 28a. On the other hand, plate cylinder 2
Table positioning pins 31 and 32, on which the positioning guides 29 and 30 come into contact, project from the bite side of the table.

In order to position the printing plate 9 on the plate cylinder 2,
After the printing plate 9 is placed on the plate guide table 25 with the U-shaped groove 9a and the plate positioning pin 28 positioned, and moved in the direction of the plate cylinder 2 (arrow Y) by the air cylinder 27, the table is moved. While being guided by the inverted V-shaped R groove 29a, the circular arc surface contacts the pin 31, and the other positioning guide surface 3
0a moves until it contacts the pin 32. Then, the plate guide table 25 is positioned by the pins 31 and 32 provided on the plate cylinder. While being held at this positioning position,
The upper teeth of the bite-side vise 12 are closed, and the printing plate 9 is fixed.
The upper teeth of the vise 12 are notched so as not to hit the guides 29 and 30.

[0012]

The plate positioning device according to the present invention is, in an automatic plate changing device of a printing press, a plate guide table that is held in an inclined position and moves in the inclining direction, and the plate is provided so as to protrude from the gripping side vise of the plate cylinder. By providing the table positioning pin which engages with the lower end of the guide table, the following effects are produced. (1) The U-shaped groove of the printing plate is used to position the plate with the plate positioning pin of the plate guide table.

Next, the plate guide table is positioned with respect to the plate cylinder. That is, since the plate is positioned via the plate guide table, no load is applied to the U-shaped groove of the plate. Therefore, the U-shaped groove is not deformed, and the mounting accuracy on the plate cylinder is improved. (2) Since the U-shaped groove is not deformed as described above,
The printing plate can be used repeatedly. (3) A table having a reverse V-shaped R groove on the one side and a guide having a plane parallel to the tangent line of the plate positioning pin on the other side is provided on the table movable in the front / rear / left / right and diagonal directions, and the reference pin facing the guide is provided on the plate cylinder. Since it can be attached to the plate cylinder, even if the plate cylinder moves in the circumferential direction, axial direction and twist direction for register adjustment, it is possible to mount the plate on the basis of the plate cylinder without returning the plate cylinder to the original position. Become.

[Brief description of drawings]

FIG. 1 is a side view of an embodiment of the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is a side view of a conventional device described in Japanese Patent Application No. 61-64890.

FIG. 4 is a diagram showing a state in which the apparatus of FIG. 3 is positioned by sliding down due to its own weight.

[Explanation of symbols]

 2 Plate cylinder 12 Vise on the gripper 25 Plate guide table 31 Table positioning pin 32 Table positioning pin

Claims (1)

[Claims] 1. An automatic plate changer for a printing press, comprising a plate guide table which is held in an inclined position and moves in the inclined direction, and a table which is provided in a vise on the gripping side of a plate cylinder so as to project from the lower end of the plate guide table. A plate positioning device comprising a positioning pin.