JPH0688402B2 - Automatic printing pressure adjusting device between plate cylinder and blanket cylinder of printing machine - Google Patents

Description

The present invention relates to an automatic printing pressure adjusting device used for adjusting printing pressure between a plate cylinder and a blanket cylinder of a printing machine.

[Prior Art] In FIGS. 3 and 4, in order to correctly transfer the printing image formed by ink on the plate on the surface of the plate cylinder 02 to the surface of the blanket cylinder 03, the space between the plate cylinder and the blanket cylinder is required. It is necessary to always keep the distance between the bodies constant. The printing image that is correctly transferred to the blanket cylinder is the paper that is conveyed by holding the surface of the impression cylinder 04 with the nail device 18.
It is transferred onto the surface of 19 by the pressure between the blanket cylinder and impression cylinder (called pressure or rubber impression pressure).

There are various thicknesses of paper used for printing, and it is important to obtain a good printed matter by always compressing the same amount of rubber 20 (called blanket) when printing any thickness of paper. .

That is, it is necessary to change the distance between the blanket cylinder 03 and the impression cylinder 04 by the amount corresponding to the paper thickness when printing on thin paper and when printing on thick paper. The general method of changing this distance is to fix the position of the impression cylinder 04 and then move the blanket cylinder 03 to the impression cylinder.
It is a structure that moves closer to or farther from 04. (This is not shown in the figure.) With this method, the rubber cylinder 03 should be moved closer to the impression cylinder 04 by the general method of moving the rubber cylinder 03 closer to the impression cylinder 04 (using an eccentric mechanism for the rubber cylinder bearing). The distance between the cylinders 02 increases. On the contrary, keep the blanket cylinder 03 away from the impression cylinder 04.
The torso distance between 02 becomes shorter.

Here, in the conventional method, when the distance between the impression cylinder 04 and the blanket cylinder 03 is changed, the plate cylinder 02 and the blanket cylinder 03 caused by it are changed.
The change in the distance between the torso between them was adjusted by using the device 011 constituted by the turnback. The point C is the center of the plate cylinder 02, and 05 is an eccentric bearing, the outer periphery 21 of which is slidably incorporated in the hole of the frame 01. The inner circumference 22 is connected to the shaft of the plate cylinder via a bearing 23. Eccentric bearing 05
Is partially connected to the turn bag 011 at the point D. The other end E of the turn bag 11 is connected to the frame 01. When the turn bag is turned, the eccentric bearing turns around the point A and moves the plate cylinder in a circular arc with the radius of the eccentricity A. Due to this position movement, the plate cylinder approaches the blanket cylinder or moves away from the blanket cylinder.

[Problems to be solved by the invention]

In the conventional apparatus as described above, it is necessary to adjust the positional relationship between the plate cylinder and the blanket cylinder with the turnback bag every time the thickness of the paper to be used for printing changes, which causes a large loss to the operating rate of the printing press.

[Means for solving problems]

The eccentric bearing of the blanket cylinder and the eccentric bearing of the plate cylinder are connected by a link mechanism or a gear mechanism so that the plate cylinder can follow the position movement of the blanket cylinder.

[Action]

When the distance between the impression cylinder and the blanket cylinder is adjusted as the thickness of the printing paper attached to the impression cylinder is changed, the distance between the blanket cylinder and the plate cylinder is automatically adjusted.

〔Example〕

1 and 2, 1 is a frame, 2 is a plate cylinder, 3
Is a blanket cylinder, and 4 is an impression cylinder.

Reference numeral 5 denotes a plate cylinder eccentric bearing, which is rotatably incorporated between the frame 1 and the bearing, rotates about the point G, and moves the position of the plate cylinder 2 by an eccentric amount c.

Reference numeral 6 denotes a blanket cylinder eccentric bearing, which is rotatably incorporated between the frame 1 and the bearing, rotates about a point H, and moves the position of the blanket cylinder 3 by an eccentric amount d.

Reference numeral 7 is a shaft, which is common between the frames 1 and has a pinion 8. By rotating the shaft 7, the distance between the blanket cylinder 3 and the impression cylinder 4 changes.

A pinion 8 is fixed to the shaft 7 by a key and meshes with the sector gear 9. When the pinion 8 is rotated, the sector gear 9 rotates.

9 is a sector gear, which is fixed to the eccentric bearing 6 with bolts,
It meshes with the pinion 8. When the sector gear 9 is rotated, the eccentric bearing 6 rotates. The rotation center of the sector gear 9 is the point H.

Reference numeral 10 denotes a pin, which pivotally mounts the turn bag 11 on the side surface of the eccentric bearing 5.

Numeral 11 is a turn bag, which is an eccentric bearing 5 via pins 10 and 12.
And the eccentric shaft 13 are connected. When the turn bag 11 is operated, the eccentric bearing 5 rotates with the eccentric shaft 13 as a reference, and the cylinder-to-cylinder distance between the plate cylinder and the blanket cylinder changes. The turn bag 11 is used only when setting the reference cylinder distance between the plate cylinder and the blanket cylinder.

A pin 12 pivotally attaches the turnback 11 to the eccentric shaft 13.

Reference numeral 13 denotes an eccentric shaft, which is rotatably incorporated in the frame 1, one end of which is connected to the turn bag 11 via a pin 12, and the other end of which is key-fixed to an arm 14. Eccentric shaft
When 13 rotates about the point J with an eccentric amount, the eccentric bearing 5 rotates via the turn bag 11.

14 is an arm, which is key-fixed to the eccentric shaft 13,
A link 16 is rotatably attached to the tip of 14 via a pin 15. The arm 14 eccentrically shifts the movement of the link 16
Tell 13.

Reference numeral 16 is a link, one end of which is connected to the arm 14 via a pin 15 and the other end of which is connected to the eccentric bearing 6 via a pin 17. The link 16 transmits the movement of the blanket barrel eccentric bearing 6 to the arm 14.

In such a device, when the shaft 7 is rotated, the pinion 8 and the sector gear 9 move, and the blanket cylinder eccentric bearing 6 rotates. Therefore, the link 16 moves as the distance between the blanket cylinder 3 and the impression cylinder 4 changes. The arm 14 and the eccentric shaft 13 are rotated by being pushed or pulled by the link 16 to move the turn bag. Due to this movement, the plate cylinder eccentric bearing 5 rotates, so that the distance change between the plate cylinder 2 and the blanket cylinder 3 caused by the change in the distance between the impression cylinder 4 and the blanket cylinder 3 is canceled, or the change is slightly suppressed. Act on.

〔The invention's effect〕

(1) The adjustment work of the turn backpack, which is required every time the paper thickness changes, is completely unnecessary, and the operating rate of the printing press is improved.

(2) There is no generation of defective printed matter that occurs when printing is performed while forgetting to adjust the turn bag.

(3) Damage to the machine due to abnormal pressure between the plate and rubber due to forgetting to adjust the turn bag is prevented.

[Brief description of drawings]

FIG. 1 is a side view of an essential part of an embodiment of an automatic printing pressure adjusting device between a plate cylinder and a blanket cylinder of a printing machine of the present invention, FIG. 2 is a plan view of FIG. 1, and FIG. 3 is a side view of a conventional structure. FIG. 4 is a plan view of an essential part of FIG. 2 ... plate cylinder, 3 ... blanket cylinder 4, impression cylinder, 5 ... plate cylinder eccentric bearing 6 ... blanket cylinder eccentric bearing, 11 ... turn backpack 13 ... eccentric shaft, 14 ... arm 16 ... link

Claims (1)

[Claims] Claim: What is claimed is: 1. In an offset printing machine of the type wherein the axial center position of the impression cylinder is fixed and the axial center position of the blanket cylinder is changed to adjust the printing pressure between the impression cylinder and the blanket cylinder. The eccentric bearing that changes the axial center position and the eccentric bearing that changes the axial center position of the plate cylinder are connected by a link mechanism, etc., and the axial center position of the plate cylinder is changed in conjunction with the change of the axial center position of the blanket cylinder. An automatic printing pressure between the plate cylinder and the blanket cylinder of the printing press, which is characterized in that the change in the distance between the plate cylinder and the blanket cylinder caused when the dimension between the impression cylinder and the blanket cylinder is changed by changing the thickness is prevented. Adjustment device.