JPH08142312A - Gapless offset rotary printing device - Google Patents

Abstract

PURPOSE: To easily adjust peripheral speed of outer peripheral faces of blanket cylinders by changing relative positions of rotary central axes of the blanket cylinders and providing a control means for increasing and decreasing butting pressures against a paper. CONSTITUTION: A control device 30 drives bearing means 20 of second, third, and fourth gapless offset rotary printing devices 12, 14, 16 corresponding to first, second, and third printing paper runout detecting means 32a, 32b, and 32c in response to magnitude of a runout of a printing paper 18 detected by the first, second, and third printing paper runout detecting means 32a, 32b, and 32c by eccentric bearing member rotating means 28 so as to change relative positions of rotary central axes of blanket cylinders 12a, 14a, and 16a for the printing paper 18. It functions as a butting pressure control means for increasing/decreasing butting pressures of the blanket cylinders 12a, 14a, and 16a against the printing paper 18.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gapless offset rotary printing apparatus having a blanket cylinder including a blanket mounted on the outer peripheral surface of a blanket cylinder body.

[0002]

2. Description of the Related Art The gapless offset rotary printing apparatus as described above is conventionally known. Gapless
In the offset rotary printing device, since the blanket forming the outer peripheral surface of the blanket cylinder does not substantially have a seam, a long printing paper rewound from the winding paper is printed on the image in the gapless offset rotary printing device. It is possible to print a large number of images in sequence without forming a substantial gap in the longitudinal direction of a long printing paper when printing the. That is, the number of images that can be printed in the longitudinal direction of one roll of roll paper (one long printing paper) is
The number can be increased as compared with the case of the conventional offset rotary printing device which is not a gapless type. This results in a reduction in the number of webs used and a less frequent supply of new webs, which in turn leads to a reduction in printing costs. A gapless offset rotary printing machine including a plurality of such gapless offset rotary printing apparatuses is also conventionally known.

[0003]

However, it has been found that the conventional gapless offset rotary printing press having a plurality of gapless offset rotary printing devices is not suitable for practical use due to color misregistration.

The reason for this is as follows. In the gapless offset rotary printing apparatus, the blanket forming the outer peripheral surface of the blanket cylinders that are in contact with each other is crushed in the contact area by the pressure of the contact, and as a result, the blanket projects before and after the contact area. ing. Therefore, when the printing paper discharged from one gapless offset rotary printing device is sandwiched between the blanket cylinders of the next gapless offset rotary printing device, the momentary resistance is caused by the forward protrusion of the contact area of the blanket. Therefore, a slight slack is generated here. Multiple gapless after second
The slack that occurs individually in the offset rotary printing device is extremely small, but the slack is added and increased as it goes through several gapless offset rotary printing devices,
Eventually, a large color shift will occur.

In the case of a conventional offset rotary printing apparatus that is not a gapless type, each time the blanket cylinder makes one revolution, a gap of a predetermined width (a part where the blanket is not exposed on the outer peripheral surface of the main body of the blanket cylinder) is a contact area. Since the slack as described above is eliminated, the color shift as described above that occurs in the conventional gapless / offset rotary printing press having a plurality of gapless / offset rotary printing devices does not occur.

In order to prevent the above-mentioned slack in the printing paper, the next gapless offset rotary printing along the moving direction of the printing paper with respect to the peripheral speed of the outer peripheral surface of the blanket cylinder in one gapless offset rotary printing apparatus. To slightly increase the peripheral speed of the outer peripheral surface of the blanket cylinder in the apparatus to generate a slight pulling force on the printing paper between one gapless offset rotary printing apparatus and the next gapless offset rotary printing apparatus. Can be considered.

[0007] And the increase in the peripheral speed is gapless
It is preferable that the offset rotary printing apparatus can be easily adjusted according to the amount of runout of the printing paper immediately before being supplied to the rotary printing apparatus.

The present invention has been made under the above circumstances, and an object of the present invention is to provide a gapless offset rotary printing capable of easily adjusting the peripheral speed of the outer peripheral surface of the blanket cylinder during operation of the gapless offset rotary printing apparatus. It is to provide a device.

[0009]

In order to achieve the object of the present invention as described above, a gapless structure according to the present invention is provided.
The offset rotary printing apparatus includes: a bearing means that rotatably supports the rotation center axis of the blanket cylinder and is capable of changing the relative position of the rotation center axis with respect to the printing paper contacting the blanket cylinder; A printing paper shake detecting means for detecting a shake of the printing paper from the moving path of the printing paper; and a bearing means corresponding to the size of the shake of the printing paper detected by the printing paper shake detecting means, and And a contact pressure control means for changing the relative position to increase or decrease the contact pressure of the blanket cylinder with respect to the printing paper.

[0010]

In the gapless offset rotary printing apparatus according to the present invention, which is configured as described above, when the printing paper shake detected by the printing paper shake detecting means becomes large, the contact is made. By the pressure control means, the bearing means is moved so that the relative position of the rotation center axis of the blanket cylinder with respect to the printing paper becomes closer to increase the contact pressure of the blanket cylinder with respect to the printing paper.

Here, when the relative position of the rotation center axis of the blanket cylinder with respect to the printing paper is brought closer by the contact pressure control means, the blanket forming the outer peripheral surface of the blanket cylinder hits the printing paper with the blanket cylinder. The rotation center axis and the rotation center axis of the other blanket cylinder are compressed by the increase of the contact pressure (that is, the increase of the pressing force against the other blanket cylinder holding the printing paper in correspondence with the blanket cylinder). The diameter of the outer peripheral surface of the blanket cylinder decreases and the peripheral velocity of the outer peripheral surface of the blanket cylinder decreases on the straight line connecting with. However, the blanket compressed on the straight line projects before and after the straight line, and the amount of the blanket projected before and after the straight line depends on the rotation of the blanket cylinder behind the straight line (that is, the blanket). It becomes larger on the downstream side than on the upstream side in the direction of rotation of the body. For this reason, when considering the blanket overhanging portion before and after the straight line, the peripheral speed of the outer peripheral surface of the blanket cylinder is larger in the blanket overhanging portion behind the straight line than in the blanket overhanging portion in front of the straight line. Become. Therefore, a slight pulling force is generated on the printing paper between one gapless offset rotary printing device and the next gapless offset rotary printing device, and the slack of the printing paper is eliminated during the above period. As a result, the above-described color shift that occurs in the conventional gapless offset rotary printing machine including a plurality of gapless offset rotary printing devices is not caused.

[0012]

1 (A) is a schematic side view of a gapless offset rotary printing press provided with a plurality of gapless offset rotary printing devices according to an embodiment of the present invention; FIG. FIG. 1B is an enlarged view of a combination of the bearing means and the main part of the contact pressure control means used in the gapless offset rotary printing apparatus according to the embodiment of the present invention shown in FIG. FIG. 1 (C) is a side view; FIG. 1 (C) is a front view of the main part of the contact pressure control means of FIG. 1 (B); FIG. 3 is a side view schematically showing elastic deformation of the blanket of the blanket cylinder in the gapless offset rotary printing device according to the embodiment of the invention.

As shown in FIG. 1A, a gapless offset rotary printing press according to an embodiment of the present invention has four units.
It is provided with first to fourth gapless offset rotary printing devices 10, 12, 14, 16 of a table. First to fourth gapless offset rotary printing apparatuses 10, 1
2, 2 and 16 are supplied with a long printing paper 18 drawn from a roll paper by a paper feeding device (not shown),
The printing paper 18 is moved in the direction indicated by the arrow A by the first to fourth gapless offset rotary printing devices 10, 12, 14, and 16. During this time, the first
To fourth gapless offset rotary printing apparatus 1
The respective predetermined images are printed from 0, 12, 14, 16 respectively.

In this embodiment, the first to fourth gapless offset rotary printing apparatuses 10, 12, 14, 1 are used.
Reference numeral 6 is used for printing images of different colors on the printing paper 18, and the first to fourth gapless offset rotary printing devices 10, 12, 14, which are sequentially arranged in the moving direction of the printing paper 18. 16 prints black, cyan, magenta, and yellow images on the printing paper 18 in this order.

Further, in this embodiment, the first to fourth gapless offset rotary printing apparatuses 10, 12, 14,
Each of the sixteen prints on both sides of the printing paper 18, and therefore has a substantially symmetrical structure above and below the printing paper 18. Further, the basic structures of the first to fourth gapless offset rotary printing apparatuses 10, 12, 14, 16 are the same as each other.

The first gapless offset rotary printing apparatus 10 is provided with a pair of blanket cylinders 10a and 10'a above and below a printing paper 18, and the pair of blanket cylinders 10a and 10'a holds the printing paper 18. It is sandwiched. A pair of plate cylinders 10b and 10'b is in contact with each of the pair of blanket cylinders 10a and 10'a. A pair of plate cylinders 10
b and 10'b have a pair of inking devices 10c and 10 '
c and the pair of dampening water devices 10d and 10'd are in contact with each other.

The second gapless offset rotary printing device 12 is also provided with a pair of blanket cylinders 12a and 12'a above and below the printing paper 18, and the pair of blanket cylinders 12a and 12'a holds the printing paper 18. It is sandwiched. The pair of blanket cylinders 12a and 12'a are in contact with the pair of plate cylinders 12b and 12'b, respectively, and the pair of plate cylinders 12b and 12'b include a pair of inkings (not shown). The device and a pair of dampening devices are in contact.

The third gapless offset rotary printing device 14 is also provided with a pair of blanket cylinders 14a and 14'a above and below the printing paper 18, and the pair of blanket cylinders 14a and 14'a holds the printing paper 18. It is sandwiched. The pair of blanket cylinders 14a and 14'a are in contact with the pair of plate cylinders 14b and 14'b, respectively, and the pair of plate cylinders 14b and 14'b have a pair of inkings (not shown). The device and a pair of dampening devices are in contact.

The fourth gapless offset rotary printing device 16 is also provided with a pair of blanket cylinders 16a and 16'a above and below the printing paper 18, and the pair of blanket cylinders 16a and 16'a holds the printing paper 18. It is sandwiched. The pair of blanket cylinders 16a and 16'a are in contact with the pair of plate cylinders 16b and 16'b, respectively, and the pair of plate cylinders 16b and 16'b include a pair of inkings (not shown). The device and a pair of dampening devices are in contact.

In this embodiment, the center axes of rotation of the blanket cylinders 12a, 14a, 16a located above the printing paper 18 in the second to fourth gapless offset rotary printing devices 12, 14, 16 respectively. The bearing means 20 that rotatably supports is configured so that the relative position of the rotation center axis with respect to the printing paper 18 can be changed.

FIG. 1B shows the bearing means 20 in an enlarged manner. The bearing means 20 corresponds to the second to fourth gapless offset rotary printing devices 12,
The blanket cylinders 12a, 14 are rotatably supported by 14 or 16 main frames 22 and are eccentric from the rotation center A with respect to the main frames 22.
a or 16a, the eccentric bearing member 26 that rotatably supports the rotation center shaft 24, and the eccentric bearing member 26 connected to the main frame 22 at a position eccentric from the rotation center A of the eccentric bearing member 26 with respect to the main frame 22. Eccentric bearing member rotating means 28 for rotating the eccentric bearing member 26
And

The eccentric bearing member rotating means 28 includes a link member 28a, one end of which is drivably connected to the eccentric bearing member 26 at a position eccentric from the rotation center A of the eccentric bearing member 26 with respect to the main frame 22. One end of the feed screw member 28b is drivably coupled to the link member 28a, and the feed screw crest 28c at the other end of the feed screw member 28b is connected to the main part as shown in FIG. A feed screw member feed drive means 28d that is drivably connected to the frame 22 is screwed. The feed screw member feed drive means 28d is provided with a female screw member (not shown) which is rotationally driven by an electric motor (not shown), and the feed screw member 28b is rotated by rotating the female screw member (not shown) in one direction or the other direction by an electric motor (not shown). Is advanced or retracted along its length.

As is apparent from FIG. 1B, when the feed screw member 28b of the eccentric bearing member rotating means 28 is moved forward or backward, the eccentric bearing member rotating means 28 moves the eccentric bearing member 26 through the link member 28a. Rotate in the clockwise or counterclockwise direction, which results in corresponding blanket cylinders 12a, 14 for the printing paper 18
a or 16a by changing the relative position of the rotation center axis 24 of the corresponding blanket cylinder 1 to the printing paper 18.
The contact pressure of 2a, 14a, or 16a is increased or decreased.

Lead screw member feed driving means of eccentric bearing member rotating means 28 of the bearing means 20 of each of the blanket cylinders 12a, 14a, 16a above the second to fourth gapless offset rotary printing devices 12, 14, 16. Two
The electric motor 8d (not shown) is electrically connected to the control device 30 as shown in FIG.

In this embodiment, the printing paper 1 is provided on the upstream side in the moving direction of the printing paper 18 with respect to the second to fourth gapless offset rotary printing devices 12, 14, 16.
Print paper 1 in the up-down direction from the normal movement route of 8
Well-known first to third printing paper shake detecting means 32a, 32b, 32c for detecting the amount of shake of 8 are arranged, and first to third printing paper shake detecting means 32a, 32 are provided.
b and 32c are electrically connected to the control device 30.

First to third printing paper shake detecting means 32
Each of a, 32b, and 32c may be a contact type, or may be a non-contact type such as an optical type.
Then, the control device 30 controls the printing paper 18 detected by the first to third printing paper shake detecting means 32a, 32b, 32c.
Second to fourth corresponding to the first to third print sheet shake detecting means 32a, 32b, 32c corresponding to the magnitude of the shake of
Gapless offset rotary printing device 12, 14,
The sixteen bearing means 20 are driven by the eccentric bearing member rotating means 28 so that the blanket cylinders 12a, 14a, 16a for the printing paper 18 (that is, for the corresponding outer peripheral surfaces of the blanket cylinders 12'a, 14'a, 16'a). And the relative position of the rotation center axis is changed to function as contact pressure control means for increasing or decreasing the contact pressure of the blanket cylinders 12a, 14a, 16a with respect to the printing paper 18.

In the above-described embodiment, the controller 30 as the contact pressure control means corresponds to the magnitude of the shake of the printing paper 18 detected by the first to third printing paper shake detecting means 32a, 32b, 32c. Are second to fourth corresponding to the first to third printing paper shake detecting means 32a, 32b, 32c.
Gapless offset rotary printing device 12, 14,
The sixteen bearing means 20 are driven by the eccentric bearing member rotating means 28 so that the blanket cylinders 12a, 14a, 16a for the printing paper 18 (that is, for the corresponding outer peripheral surfaces of the blanket cylinders 12'a, 14'a, 16'a). The relative positions of the central axes of rotation are made close to each other to increase the contact pressure of the blanket cylinders 12a, 14a, 16a with respect to the printing paper 18.

Then, as shown in FIG. 1D, the blanket 34 constituting the outer peripheral surface of the blanket cylinders 12a, 14a, 16a increases the contact pressure of the blanket cylinders 12a, 14a, 16a against the printing paper 18. (That is,
Another blanket cylinder 12 that holds the printing paper 18 in correspondence with the blanket cylinders 12a, 14a, 16a.
‘A, 14 ′ a, 16 ′ a pressure increase), a straight line connecting the rotation center axis and the other rotation center axes of the blanket cylinders 12 ′ a, 14 ′ a, 16 ′ a On B, blanket cylinders 12a, 14a, 16a
The diameter of the outer peripheral surface of the blanket cylinders 12a, 14 is reduced.
The peripheral speed of the outer peripheral surfaces of a and 16a decreases. However, the blanket 34 compressed on the straight line projects before and after the straight line, and the amounts of the front projecting portion 34a and the rear projecting portion 34b of the blanket 34 before and after the straight line are different from each other.
Due to the influence of the rotation of a, 14a, 16a, the rear protruding portion 34b of the straight line B is more rearward than the front protruding portion 34a.
(That is, the blanket cylinders 12a, 14a, 16a are larger on the downstream side than on the upstream side in the rotation direction).
Therefore, the blanket 34 before and after the straight line B is
Front protruding portion 34a and rear protruding portion 34b
Considering the blanket cylinders 12a, 14a, 1
The peripheral velocity of the outer peripheral surface of 6a is 34 in front of the straight line B.
The rear protruding portion 34b of the blanket 34 behind the straight line B is larger than the front protruding portion 34a. Therefore, a slight pulling force is exerted on the printing paper 18 between one gapless offset rotary printing device 10, 12, or 14 and the next gapless offset rotary printing device 12, 14, or 16, between the above. The occurrence of slack in the printing paper 18 is eliminated. As a result, the above-described color shift that occurs in the conventional gapless offset rotary printing machine including a plurality of gapless offset rotary printing devices is not caused.

The first to fourth gapless offset rotary printing devices 10, 12, 14, 16 do not print on both sides of the printing paper 18 as described above, but only on one side. It goes without saying that it is also good. In this case, one of the first to fourth gapless offset rotary printing devices 10, 12, 14, 16 is used.
Pair of blanket cylinders 10a, 10'a or 12a, 1
2'a or 14a, 14'a or 16a, 16'a
Of the blanket cylinders 10a, 10'a or 12a, 12'a or 14a, 14'a or 16a, instead of the plate cylinder, the inking device and the dampening device corresponding to either one of An impression cylinder is used that clamps the printing paper 18 in cooperation with the other one of 16'a.

In this case, the first to fourth gapless
When the four impression cylinders (not shown) used in the offset rotary printing devices 10, 12, 14, 16 have the same diameter, the corresponding pair of blanket cylinders 10a, 10 '.
Each of the rotational speeds is set to rotate at the same angular speed as the angular speed of the other one of a or 12a, 12'a or 14a, 14'a or 16a, 16'a.

[0031]

As described in detail above, in the gapless offset rotary printing apparatus according to the present invention, the peripheral speed of the outer peripheral surface of the blanket cylinder can be easily adjusted during operation of the gapless offset rotary printing apparatus. .

[Brief description of drawings]

FIG. 1A is a schematic side view of a gapless offset rotary printing press including a plurality of gapless offset rotary printing devices according to an embodiment of the present invention;
(B) is an enlarged side view showing the combination of the bearing means and the main part of the contact pressure control means used in the gapless offset rotary printing apparatus according to the embodiment of the present invention (A). FIG. 3C is a front view of the main part of the contact pressure control means of FIG. 3B; FIG. 3D is a gapless offset rotary printing apparatus according to one embodiment of the present invention of FIG. FIG. 6 is a side view schematically showing elastic deformation of the blanket of the blanket cylinder in FIG.

[Explanation of symbols]

10 ... The first gapless offset rotary printing device,
10a, 10'a ... Blanket cylinder, 10b, 10'b
... plate cylinder, 10c, 10'c ... inking device, 10d,
10'd ... Damping water device, 12 ... 2nd gapless offset rotary printing device, 12a, 12'a ... Blanket cylinder, 12b, 12'b ... Plate cylinder, 14 ... 3rd gapless offset rotary printing device , 14a, 14'a ... Blanket cylinder, 14b, 14'b ... Plate cylinder, 16 ... Fourth gapless offset rotary printing device, 16a, 16
'A ... blanket cylinder, 16b, 16'b ... plate cylinder, 18
... Printing paper, 20 ... Bearing means, 22 ... Main frame, A
Rotation center, 24 ... Rotation center shaft, 26 ... Eccentric bearing member, 28 ... Eccentric bearing member rotating means, 28a ... Link member, 28b ... Feed screw member, 28c ... Feed screw thread, 28
d ... Feed screw member feed driving means, 30 ... Control device (contact pressure control means), 32a ... First printing paper shake detecting means, 32b ... Second printing paper shake detecting means, 32c ... Third printing paper Shake detection means, 34 ... Blanket, 34
a: front protruding portion, 34b: rear protruding portion, B
… Straight line.

Claims (2)

[Claims] 1. A bearing means for rotatably supporting a central axis of rotation of the blanket cylinder and capable of changing the relative position of the central axis of rotation to the printing paper contacting the blanket cylinder; A printing paper shake detecting means for detecting a shake of the printing paper from the moving path; and a bearing means for the rotation center axis of the blanket cylinder with respect to the printing paper in response to the size of the printing paper shake detected by the printing paper shake detecting means. Change the relative position,
A gapless offset rotary printing apparatus, comprising: contact pressure control means for controlling the contact pressure of the blanket cylinder with respect to the printing paper. 2. The bearing means is rotatably supported by the main frame of the gapless offset rotary printing apparatus, and rotatably supports the rotation center axis of the blanket cylinder at a position eccentric from the rotation center of the main frame. An eccentric bearing member, and eccentric bearing member rotating means for connecting the eccentric bearing member at a position eccentric from the rotation center of the eccentric bearing member with respect to the main frame and rotating the eccentric bearing member with respect to the main frame. The gapless offset rotary printing apparatus according to claim 1.