JP5286705B2 - Automatic plate changer for offset printing machine - Google Patents

Description

  The present invention relates to an automatic plate changer for mounting a plate on a plate cylinder of an offset printing machine.

  In the color printing operation of an offset printing machine, multiple colors are printed on the same paper, etc. In order to obtain printed matter with excellent quality, the position of the pattern printed by each color printing unit is completely It is important to match. Therefore, a reference hole is formed in advance in each color plate, and the pattern position of each color is output in accordance with this reference hole to make the plate. In order to mount the plate on the plate cylinder, the plate is mounted while aligning the reference hole of the plate and the reference pin of the plate cylinder. However, this work has a problem that high accuracy is required, it is difficult and time consuming, and experience and skill are required.

Therefore, as described in Patent Documents 1 and 2, an apparatus for automatically performing this plate exchange has been proposed and put into practical use.
Japanese Patent Laid-Open No. 6-8403 JP 2000-62146 A

  However, in the conventional automatic plate change work, every time it is installed, there is a problem of misregistration in printing and adjustment is performed, and although the load of plate change work is reduced, there is a problem that printing efficiency does not increase easily. there were.

  The present invention is obtained as a result of diligent examination of the cause of misregistration along the automatic plate change operation of the offset printing press, and solves the conventional problems. It is an object of the present invention to provide an automatic plate changer for an offset printing machine that does not cause misregistration of printing. A further object of the present invention is to provide an automatic plate changer capable of efficiently exchanging plates in an offset printing machine and realizing registering at once.

According to a first aspect of the present invention, there is provided an automatic plate changer for an offset printing machine, wherein the plate changer is guided by a support attached to the printing unit and is inclined up and down toward the vice-side vise of the plate cylinder; A printing plate base which is guided by the plate changer base and which is moved up and down and provided with a printing plate reference pin for a plate to be mounted on the plate cylinder, and the printing plate base is paired with a side facing the plate cylinder. A plate cylinder abutting reference block is provided, and the plate lateral positioning reference block of the plate cylinder abutting reference block is a V-shaped groove , and a plate cylinder abutting pin is abutted against the V-shaped groove from the vertical direction. Thus, the automatic plate changer of the offset printing machine is characterized in that the lateral gap between the pin and the V-shaped groove is filled, and the lateral position of the plate with respect to the plate cylinder can be fixed .

  According to the present invention, in the automatic plate changer for an offset printing press according to claim 1, the plate changer frame has a frame abutment block, and the frame abutment block is engaged with the frame of the plate cylinder. This is an automatic plate changer for an offset printing machine.

According to the present invention, in the automatic plate changer for an offset printing machine according to claim 1, a timer is applied to the lower end lower limit confirmation limit of the plate changer base and the lower end lower limit confirmation limit of the plate base, so that the lower end is lowered. The automatic plate changer for an offset printing machine is characterized in that the ramping time is prevented and the convergence time is reduced by extending the positioning time when the plate cylinder rotates to the insertion position.

  According to the present invention, the registration accuracy in the automatic plate changing work is improved, the registration can be realized in one time without adjustment, the setup time for changing the pattern can be shortened, the adjustment paper can be reduced, and the printing work efficiency is improved. .

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1, 2, and 3 which are partially enlarged schematic views and FIGS. 4, 5, 6 and 7 which are partially schematic views.

  As shown in FIGS. 4 to 7, the automatic plate changing operation of the offset printing machine of the present invention is generally performed as follows. (1) First, a plate changer frame (hereinafter, referred to as a plate exchanging device) that is guided by a support base (not shown) attached to the printing unit and tilts up and down (or advances and retreats) toward the heel side vise 10 of the plate cylinder 12. A plate (new plate) 3 is mounted on a plate base 2 on the plate 1 (which is abbreviated as a frame) that moves up and down (or advances and retreats) itself (FIG. 4A). (2) Next, the gantry 1 is automatically lowered to contact with the plate cylinder frame 6 of the printing unit. The gantry 1 and the plate cylinder frame 6 are brought into contact with each other at the abutment block 5 (FIG. 4B). (3) Next, the contact between the abutting block 5 and the plate cylinder frame 6 is confirmed by a sensor or the like, and the plate cylinder 12 is rotated to the plate holding position (FIG. 5A). (4) Next, the plate holding position is confirmed by a sensor or the like, and the plate base 2 is lowered and the plate is picked up. At this time, the plate is positioned by aligning the plate cylinder abutting pin 8 with the plate longitudinal positioning reference block 7a and the plate lateral positioning reference groove 7b of the plate cylinder abutting reference block 7 (FIG. 5B). (5) When plate preparation starts, the lowered printing plate base rises to the base (FIG. 6A). (6) Next, after positioning, the plate cylinder rotates and winding is completed (FIG. 6B). (7) Next, the cradle is raised and the plate replacement work is completed (FIG. 7).

  The automatic plate replacement work of the offset printing machine includes a work of storing the old version removed from the plate cylinder before the above-mentioned plate (new version) is mounted. Usually, the automatic plate changer is equipped with an old plate holding stand (not shown) for temporarily storing the old plate in a cassette shape, and is controlled so that it can be moved relatively at a predetermined timing with respect to the elevation of the plate plate stand. ing.

  When the plate cylinder rotates and aligns the plate cylinder abutting pin with the plate cylinder abutting reference block, conventionally, the plate lateral positioning reference groove has a semicircular U-shaped cross section, and its diameter is always relative to the diameter of the plate cylinder abutting pin. Because it was set to plus, there was a misregistration due to the mounting condition. In the present invention, the registration accuracy is improved by making the plate lateral positioning reference block 7b a block structure having a V-shaped groove as shown in FIG. In addition, it is preferable to quench or carburize the contact portion of the block lateral positioning reference block 7b having a V-shaped block structure according to the present invention with the plate cylinder abutting pin 8.

  As a result, the first registration is performed to determine the position of the plate cylinder, which is used as the reference immobile origin, and the plate cylinder adjustment is not performed for the second and subsequent times, and is also returned to the virtual origin on the servo motor during plate replacement. By avoiding it, the registration at one time is reproduced. At this time, if the registration is misaligned, it is necessary not to adjust the plate cylinder, but to correct the plate itself to improve the registration accuracy of the plate and eliminate the misregistration.

Next, the conventional method for confirming the contact between the gantry 1 and the plate cylinder frame 6 has only a problem of reproducibility because the abutment block 5 is merely aligned with the positioning groove on the plate cylinder frame plane. In this way, the positioning accuracy can be improved in addition to the effect of the block cylinder abutting reference block having a V-shaped block structure executed after this operation. That is, the reference of the gantry 1 and the plate cylinder frame 6 is surely taken, and the mesh structure is made to be engaged, the timer for confirming the descent is used, and the timer can be moved to the next operation by setting the timer at the descending end. Move down to be able to get the plate.

  Next, as shown in FIG. 3, when the plate is mounted on the plate base, there is a difference in diameter between the plate punch hole and the plate reference pin, and a misalignment of about ± 0.06 mm occurs at the maximum. Can be mentioned. While the current CTP plate punch hole is 8 mm ± 0.03, the printing plate reference pin diameter is 8 mm + 0−0.03, and the maximum diameter difference is ± 0.06 mm. This is because there is no positioning jig or the like for setting the printing plate standard pin 4 in the middle of the plate punch hole 11. As a method for solving this, in the present invention, the plate standard pin 4 is made to abut against the left or the right of the plate punch hole 11 when the plate is mounted. This greatly improves the accuracy of registration. This is also carried out when mounting on a CTP machine in the printing plate process.

    As described above, in the present invention, the registration accuracy can be improved by changing the structure of the automatic plate changer. However, in order to make the effect more reliable, the present invention further includes a sensor or the like for positioning. As a countermeasure against unstable positioning due to chattering at the end points or servo motor convergence pulses, check the lower end and the lower end confirmation limit switch to prevent chattering. . Furthermore, as a countermeasure against the ramping of the convergence pulse, it is possible to stabilize the rotation to the plate insertion position of the plate cylinder by lengthening the positioning time of the rotation confirmation servo motor.

FIG. 5 is a partially enlarged cross-sectional view illustrating the shape of a plate lateral positioning reference block of a plate cylinder abutting reference block according to an embodiment of the present invention. It is a partial expansion schematic diagram explaining the meshing structure of a mount frame and a frame in one embodiment of the present invention. In one Example of this invention, it is the partial expansion schematic diagram explaining the abutment unification to the right and left at the time of plate mounting | wearing. It is a partial schematic diagram explaining the automatic plate change work process of this invention. It is a partial schematic diagram explaining the continuation of the automatic plate change work process shown in FIG. It is a partial schematic diagram explaining the continuation of the automatic plate change work process shown in FIG. FIG. 7 is a partial schematic diagram illustrating the continuation of the automatic plate change work process shown in FIG. 6.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Plate change device stand, stand 2 ... Printing plate stand 3 ... Plate, new plate, plate 4 ... Plate reference pin 5 ... Abutting block 6 ... Plate cylinder frame 7 ... Plate cylinder abutting reference block 7a ... Plate longitudinal direction positioning reference block 7b ... Plate lateral direction positioning reference block 8 ... Plate cylinder abutting pin 9 ... Manual plate mounting pin 10 ... Vise Mechanism 11: Plate punch hole 12: Plate cylinder (plate cylinder unit)

Claims (3)

In an automatic plate changer for an offset printing machine,
A plate changer base that is guided by a support base attached to the printing unit and tilts up and down toward the vice-side vise of the plate cylinder, and a plate that is guided by the plate changer base and moves up and down and is attached to the plate cylinder. A printing plate base provided with a printing plate reference pin, wherein the printing plate base is provided with a pair of plate cylinder abutting reference blocks on a side facing the plate cylinder, and the plate cylinder abutting reference block is positioned in the lateral direction of the plate. The reference block is a V-shaped groove , and a plate cylinder abutting pin is abutted against the V-shaped groove from the vertical direction, thereby filling a lateral gap between the pin and the V-shaped groove, An automatic plate changer for an offset printing machine, characterized in that the lateral position relative to the plate cylinder can be fixed . 2. The automatic plate change of an offset printing press according to claim 1, wherein the plate changer frame has a frame abutment block, and the frame abutment block engages with a frame of the plate cylinder. 3. apparatus. A timer is applied to the lower end lower limit confirmation limit of the plate changer base and the lower end lower limit confirmation limit of the printing plate base to prevent rampage at the lower end, and to determine the positioning time when the plate cylinder rotates to the insertion position. 2. The automatic plate changer for an offset printing press according to claim 1, wherein the convergence pulse is reduced by increasing the length.

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