JPH081904A - Gapless blanket cylinder, and gapless offset press employing gapless blanket cylinder - Google Patents

Abstract

PURPOSE:To continuously print images on an ink plate to web paper without allowing color slippage to occur in a large extent. CONSTITUTION:A blanket cylinder main body 24c in a hollow cylindrical shape, having a slit 24b arranged coaxially with the axis of rotation 24a and surrounding the outer peripheral face of the axis of rotation and extending from one end to the other end along the rotational centerline of the axis of rotation and covered at its outer peripheral face with a cylindrical blanket 24e, and a mechanism 24d for changing the diameter of the blanket cylinder main body, that is positioned between the rotational centerline and the blanket cylinder main body for supporting the blanket cylinder main body against the rotational centerline and changes the diameter on the outer peripheral face of the blanket cylinder main body to the rotational centerline of the axis of rotation, are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gapless blanket cylinder having an outer peripheral surface covered with a cylindrical blanket and a gapless offset printing machine using the gapless blanket cylinder.

[0002]

2. Description of the Related Art Gapless offset printing machines intended to continuously print a plate of a plate cylinder on a roll-up printing paper are known.

In a gapless offset printing machine, a plate is wound in a substantially gapless manner, and the dampening water and ink are supplied from the dampening water means and the inking means, and the outer peripheral surface is covered with a cylindrical blanket. And contact the plate cylinder and the ink plate image is transferred from the plate of the plate cylinder, and the take-up printing paper is sandwiched between the blanket cylinder and the blanket cylinder in cooperation with the blanket cylinder to rotate in the opposite direction to the blanket cylinder. Each of which has at least an impression cylinder which transfers the ink plate image from the blanket cylinder to the roll-up printing paper while feeding the roll-up printing paper, and which are arranged in series in the transport direction of the roll-up printing paper. Equipped with a printing unit. Then, the winding printing paper is supplied to the plurality of printing units in a state where the tension along the conveying direction is applied to the winding printing paper by the tension applying means.

Here, each impression cylinder of the plurality of printing units is constituted by another blanket cylinder whose outer peripheral surface is covered with a cylindrical blanket, and each of the plurality of printing units is a plate. Are wound substantially gaplessly and are supplied with dampening water and ink from the dampening water means and the inking means to contact another blanket cylinder to transfer the ink plate image from the plate to the other blanket cylinder. It may be further equipped with one plate cylinder.

[0005]

In the conventional gapless offset printing machine configured as described above, the winding printing paper has a plurality of printing units in spite of the tension load means when actually operating. When it passed, a large color shift occurred and it was not practical.

This is because every time the roll-up printing paper passes through one printing unit, the adhesive force of the ink causes a slight wavy portion and a slack portion in the circumferential direction of the blanket cylinder, which causes tension. In conventional offset printing machines that are not gapless, the above-mentioned wave is eliminated by the rolled printing paper passing through the gap of the blanket cylinder.

The present invention has been made under the above circumstances, and an object of the present invention is to allow an ink plate image to be continuously printed on a roll-up printing paper without causing a large color shift in a gapless offset printing machine. A gapless blanket cylinder and a gapless offset printing machine using the gapless blanket cylinder.

[0008]

In order to achieve the above-mentioned object of the present invention, a gapless blanket cylinder according to the present invention is characterized in that the diameter of the outer peripheral surface around the rotation center axis can be changed. There is.

The gapless blanket cylinder according to the present invention has: a rotation center axis; a hollow cylindrical shape, and is arranged concentrically with respect to the rotation center axis to surround the outer peripheral surface of the rotation center axis, A blanket cylinder body having at least one slit extending from one end to the other end in a direction along the axis of rotation of the shaft, the outer peripheral surface of which is covered with a cylindrical blanket; and a center of rotation axis and the blanket. A blanket cylinder body diameter changing means that is interposed between the cylinder body and supports the blanket cylinder body with respect to the rotation center axis, and that changes the diameter of the outer peripheral surface of the blanket cylinder body with respect to the rotation center line of the rotation center axis. It can also be characterized by having ;.

A gapless offset printing machine using a gapless blanket cylinder according to the invention is also:
The gapless blanket cylinder is characterized in that the diameter of the outer peripheral surface around the rotation center axis can be changed.

A gapless offset printing machine using a gapless blanket cylinder according to the invention further comprises: a plate in which the plate is wound substantially gapless and the fountain solution and the ink are supplied from the fountain solution means and the inking means. Winding between the cylinder, a blanket cylinder that covers the outer peripheral surface with a cylindrical blanket and contacts the plate cylinder to transfer the ink plate image from the plate of the plate cylinder, and the blanket cylinder in cooperation with the blanket cylinder. Each of them has at least an impression cylinder that holds the printing paper and rotates in the opposite direction of the blanket cylinder to feed the take-up printing paper to transfer the ink plate image from the blanket cylinder to the take-up printing paper. A plurality of printing units arranged in series in the paper conveying direction; for take-up printing with a tension applied to the take-up printing paper along the conveying direction Each of the blanket cylinders of the printing units arranged in at least the second or more of the plurality of printing units in the transport direction of the roll-up printing paper, comprising: A rotation center axis; having a hollow cylindrical shape, arranged concentrically with respect to the rotation center axis to surround the outer peripheral surface of the rotation center axis, and one end to the other end in the direction along the rotation center line of the rotation center axis A blanket cylinder body having at least one slit extending to the outer peripheral surface of which a cylindrical blanket is covered; and, with respect to the rotation center axis, interposed between the rotation center axis and the blanket cylinder body. Blanket cylinder body diameter changing means for changing the diameter of the outer peripheral surface of the blanket cylinder body with respect to the rotation center line of the rotation center axis. And the diameter of the outer peripheral surface of the blanket cylinder body of each of the blanket cylinders of the printing units arranged at least at the second and subsequent positions is one upstream in the transport direction of the roll-up printing paper. It can be characterized in that it is set to be larger than the diameter of the outer peripheral surface of the blanket cylinder body of the blanket cylinder.

In each of the gapless blanket cylinder and the gapless offset printing machine using the gapless blanket cylinder, the blanket cylinder body diameter changing means is arranged at a plurality of positions separated from each other in the circumferential direction of the rotation center axis. From the rotation center axis in the radial direction, a blanket cylinder body support member that radially extends toward the cylinder body, supports the blanket cylinder body at the extension end, and is freely retractable in the radial direction of the rotation center axis with respect to the rotation center axis. And a protrusion distance adjusting means for adjusting the protrusion distance of the blanket cylinder body supporting member.

Further, in the gapless offset printing machine using the gapless blanket cylinder according to the present invention, each impression cylinder of the plurality of printing units is another blanket cylinder whose outer peripheral surface is covered with a cylindrical blanket. In each of the plurality of printing units, the plate is wound substantially in a gapless manner, and the dampening water and the ink are supplied from the dampening water means and the inking means to contact another blanket cylinder. One more from the edition
It can further comprise another plate cylinder that transfers the ink plate image to one blanket cylinder.

[0014]

In the gapless blanket cylinder according to the present invention and the gapless offset printing machine using this gapless blanket cylinder, which is characterized as described above, in the gapless blanket cylinder, the outer peripheral surface about the center axis of rotation is used. By changing the diameter of the blanket, it is possible to change the angular velocity of the outer peripheral surface of the blanket, and thus the transport speed of the roll of print paper that is transported in contact with the outer peripheral face of the blanket (ie, the load of the roll print paper is applied. Tensile force) can be changed.

Accordingly, in a gapless offset printing machine for multi-color printing using a plurality of gapless blanket cylinders, at least the second and subsequent blanket cylinders in the plurality of gapless blanket cylinders are arranged in the transport direction of the rolled printing paper. The diameter of the outer peripheral surface of the blanket cylinder is set to be larger than the diameter of the outer peripheral surface of the blanket cylinder that is positioned upstream in the transport direction of the roll-up printing paper, and the angular velocity of the outer peripheral surface of the blanket cylinder that is positioned upstream in the above direction. A large angular velocity is generated on the outer peripheral surface of the blanket cylinder that follows the blanket cylinder located on the upstream side by one,
As a result, the transfer speed of the roll-printing paper (that is, the tensile force applied to the roll-printing paper) conveyed by contacting the outer peripheral surface of the blanket cylinder following the blanket cylinder located on the upstream side is brought to the above-mentioned one. It can be made higher than the above-mentioned transport speed in the blanket cylinder located on the upstream side (that is, the tensile force applied to the rolled printing paper).

Due to this increase in the tensile force, every time the roll-up printing paper passes through one blanket cylinder, the adhesive force of the ink slightly pulls it in the circumferential direction of the blanket cylinder to form a wavy portion and a slack portion. Is effectively suppressed, which effectively prevents the tension balance from being disturbed.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Various embodiments of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1A is a side view schematically showing an example of a gapless offset printing machine using a gapless blanket cylinder according to an embodiment of the present invention, and FIG. FIG. 6 is a side view schematically showing another embodiment of a gapless offset printing press using a gapless blanket cylinder according to an embodiment of the present invention.

The gapless offset printing machine shown in FIG. 1A has four printing units 10, 12, 14 for printing four colors of black, cyan, magenta and yellow on one surface of a long paper roll. 16 is provided. Each of the four printing units 10, 12, 14 and 16 has a plate wound substantially gaplessly and is supplied with dampening water and ink from a known dampening solution means 18 and a known inking means 20. The plate cylinder 22, a blanket cylinder 24 which is covered with a cylindrical blanket on the outer peripheral surface and contacts the plate cylinder 22 to transfer the ink plate image from the plate of the plate cylinder 22, and the blanket cylinder 24 in cooperation with the blanket cylinder 24. Take-up printing paper 26 with 24
And an impression cylinder 28 which transfers the ink plate image from the blanket cylinder 24 to the roll-up printing paper 26 while feeding the roll-up printing paper 26 by rotating the blanket cylinder 24 in a direction opposite to that of the blanket cylinder 24.
And at least four printing units 10, 1
2, 14, 16 are arranged in series in the transport direction of the roll-up printing paper 26. Then, these four printing units 10, 12, 1 are arranged along the transportation path of the roll-up printing paper 26.
Before and after 4, 16, the winding printing paper 2 is applied with tension applied to the winding printing paper 26 along the conveying direction.
Known tension load means 29a, 29b for supplying 6 to the four printing units 10, 12, 14, 16 are arranged.

The overall construction of the gapless offset printing machine shown in FIG. 1A is well known, and the construction of each of the four printing units 10, 12, 14, 16 is also a three-cylinder type offset printing unit. Since it is well known, the detailed structure shown above will not be described.

The gapless offset printing machine shown in FIG. 1B has four printing units 30, 32 and 34 for printing four colors of black, cyan, magenta and yellow on both sides of a long paper roll. , 36. In the gapless offset printing machine of FIG. 1B, each of the four printing units 30, 32, 34 and 36 is four printing units 10, 12 and 14 of the gapless offset printing machine of FIG. , 16 instead of the respective impression cylinders 28, another blanket cylinder 24 'having a cylindrical blanket on its outer peripheral surface is used, and the plate is wound in a substantially gapless manner. Damping water and ink are supplied from 18 'and inking means 20'.
It further comprises another plate cylinder 22 'which contacts one blanket cylinder 24' and transfers the ink plate image from the plate to the other blanket cylinder 24 '. The other configuration is the same as the configuration of the gapless offset printing machine of FIG. 1A, the same constituent members are denoted by the same reference numerals, and detailed description thereof will be omitted.

The overall construction of the gapless offset printing machine shown in FIG. 1B is well known, and each of the four printing units 30, 32, 34 and 36 is also a BB type offset printing unit. Since it is well known, the detailed structure shown above will not be described.

The roll-up printing paper 26 in each of the gapless offset printing machines shown in FIGS. 1A and 1B.
The transport direction of the paper is from left to right as indicated by the arrow on the roll-up printing paper 26.

Further, four printing units 10, 12, 14, 16 and four printing units 30, respectively, in the gapless offset printing machine shown in FIGS. 1A and 1B,
Each of 32, 34, and 36 can also be used to transfer an ink plate image of a color other than those described above onto one surface or both surfaces of the roll-up printing paper 26, and the gapless structure shown in FIGS. If each offset printing machine has a plurality of printing units (that is, two or more printing units), it is possible to increase or decrease according to the color of the ink plate image transferred to one surface or both surfaces of the roll-up printing paper 26. Needless to say.

The gapless offset printing machine shown in FIGS. 1A and 1B is different from the conventional gapless offset printing machine having such a construction in that the second and subsequent ones in the conveying direction of the roll-up printing paper 26. Printing units 12, 14, 16 or 12 ', 14', 1 arranged in
The blanket cylinders 24, 24 'of the printing unit in which the diameter of the outer peripheral surface of each of the blanket cylinders 24, 24' of 6'is located one upstream side in the transport direction of the roll-up printing paper 26.
It is set to be larger than the diameter of the outer peripheral surface of. However, the difference in the diameter of these outer peripheral surfaces is very slight, and the purpose is the respective printing units 12, 1.
By newly applying a pulling force to the roll-up printing paper 26 between 4, 16 or 12 ′, 14 ′, 16 ′, the blanket is generated by the adhesive force of the ink each time the roll-up printing paper 26 passes through one printing unit. This is to prevent the body 24 or 24 'from being slightly stretched in the circumferential direction to undulate, so that the color shift does not occur to the extent that a normal person can immediately see it.

2 (A) and 2 (B), in order to show a structure for changing the diameter of the outer peripheral surface of the blanket cylinder, a cross section and a part of the front surface of the blanket cylinder 24 are enlarged and shown. ing. The structure of the other blanket cylinder 24 ′ is the same as that of the blanket cylinder 24.

The blanket cylinder 24 has a hollow cylindrical shape and a rotation center shaft 24a whose both ends in the longitudinal direction are supported by a known rotation supporting means (not shown) by inputting a rotation driving force from a known rotation driving source (not shown). Having a rotation center axis 24a
A blanket having at least one slit 24b which is concentrically arranged with respect to and surrounds the outer peripheral surface of the rotation center shaft 24a and extends from one end to the other end in the direction along the rotation center line of the rotation center shaft 24a. Body 24c
And the outer peripheral surface of the blanket cylinder body 24c with respect to the rotation center line of the rotation center shaft 24a by supporting the blanket cylinder body 24c with respect to the rotation center shaft 24a by being interposed between the rotation center shaft 24a and the blanket cylinder body 24c. Blanket cylinder body diameter changing means 24d for changing the diameter of the
The outer peripheral surface of the blanket body 24c is covered with a tubular rubber blanket 24e.

The blanket cylinder main body 24c is made of a material such as metal that is hard but has elasticity, and the rubber blanket 24e is one in which the blanket cylinder main body 24c has its outer peripheral surface diameter changed by the blanket cylinder main body diameter changing means 24d. However, due to its own elasticity, it adapts to the change in the diameter and does not fall off the outer peripheral surface, and it does not cause wrinkles.

In this embodiment, the blanket cylinder body diameter changing means 24d extends radially toward the blanket cylinder body 24c from each of a plurality of positions spaced from each other in the circumferential direction of the rotation center axis 24a, and the blanket cylinder at the extending end. A plurality of blanket cylinder body support members 40 that support the main body 24c and are freely retractable in the radial direction of the rotation center axis 24a with respect to the rotation center axis 24a, and a blanket cylinder body support member 4 from the rotation center axis 24a in the radial direction.
And a protrusion distance adjusting means 42 for adjusting the protrusion distance of 0.

In this embodiment, the rotation center shaft 24a is formed in a hollow cylindrical shape, and the protrusion distance adjusting means 42 is formed on the peripheral surface of each of the plurality of blanket cylinder main body support members 40. A thread groove screwed onto the outer peripheral wall,
And a motor M which is connected to the inner end of each of the plurality of blanket cylinder body supporting members 40 in the center hole of the rotation center shaft 24a and rotates the blanket cylinder body supporting member 40. The outer ends of the respective 40 are rotatably connected to the inner peripheral surface of the blanket body 24c so as not to move in the radial direction of the rotation center shaft 24a. The plurality of motors M are controlled by a controller (not shown) to rotate the corresponding blanket cylinder body supporting members 40 in the same direction and by the same distance.

Blanket cylinder 2 constructed as described above
In 4, the diameter of the outer peripheral surface of the blanket cylinder main body 24c having the slits 24b is controlled by controlling a plurality of motors M by a controller (not shown) to rotate the blanket cylinder main body support member 40 in the same direction by the same distance. Can be expanded or contracted to obtain a desired diameter.

In the above-described embodiment, the blanket cylinder 24 configured as described above has four printing units 10, 12 in each of the gapless offset printing machines shown in FIGS. 1A and 1B. 14, 16 and 4
When installed in each of the printing units 30, 32, 34, 36 of the table, the slits 24b are aligned with the stepless seam of the plate (not shown) on the outer peripheral surface of the corresponding plate cylinder 22. In FIG. 1A and FIG. 1B, the matching state is shown by the alignment marks of the blanket cylinder 24 and the corresponding plate cylinder 22.

The protrusion distance adjusting means 42 is not limited to the above-described embodiment, and for example, one motor is arranged at the center of the rotation center shaft 24a, and the rotation of this one motor is controlled by a gear train, a cam, a link or the like. It is also possible to drive the plurality of blanket cylinder body supporting members 40 by transmitting to the plurality of blanket cylinder body supporting members 40 via a known rotational force transmitting means, or to employ hydraulic pressure as a drive source to thereby realize a plurality of blanket cylinder body supporting bodies. The support member 40 can also be configured as a piston / cylinder assembly.

It is also possible to manually drive the plurality of blanket cylinder body supporting members 40 without using a motor or hydraulic pressure as a drive source.

The arrangement of the plurality of blanket cylinder body supporting members 40 on the rotation center shaft 24a is not limited to that shown in FIG. 2, and in short, the entire outer peripheral surface of the blanket cylinder body 24c is made substantially uniform in diameter. It is sufficient if it can be expanded or contracted.

Further, four printing units 10, 12, 14, 16 and four printing units 30, 32, 34, in each of the gapless offset printing machines shown in FIGS. 1A and 1B, are shown. Expanding or contracting the diameter of the outer peripheral surface of the blanket cylinder 24 or 24 'in 36, respectively, can be performed with or without the gapless offset printing machine in operation.

If the diameter of the outer peripheral surface of the blanket cylinder 24 or 24 'is expanded or contracted during the operation of the gapless offset printing machine, the state of color misregistration will be observed during actual printing. Can be adjusted more precisely.

[0037]

As described in detail above, in the gapless blanket cylinder according to the present invention and the gapless offset printing machine using the gapless blanket cylinder, the ink plate image is continuously printed on the roll-up printing paper without causing a large color shift. Can be printed.

[Brief description of drawings]

FIG. 1A is a side view schematically showing an embodiment of a gapless offset printing machine using a gapless blanket cylinder according to an embodiment of the present invention,
(B) is a side view schematically showing another embodiment of a gapless offset printing machine using a gapless blanket cylinder according to an embodiment of the present invention.

FIG. 2A is a schematic cross-sectional view of the blanket cylinder showing a structure for changing the diameter of the outer peripheral surface of the blanket cylinder, and FIG. 2B is a front view of the blanket cylinder of FIG. It is a front view which expands and shows a part.

[Explanation of symbols]

10, 12, 14, 16 ... Printing unit, 18, 18 '
... fountain solution means, 20, 20 '... inking means, 22,
22 '... plate cylinder, 24, 24' ... blanket cylinder, 26 ...
Winding printing paper, 28 ... impression cylinder, 29a, 29b ... tension loading means, 30, 32, 34, 36 ... printing unit, 24
a ... central axis of rotation, 24b ... slit, 24c ... blanket cylinder main body, 24d ... blanket cylinder main body diameter changing means, 24e ... blanket, 40 ... blanket cylinder main body supporting member, 42 ... projection distance adjusting means, M ... motor.

Claims (7)

[Claims] 1. A gapless blanket cylinder, wherein a diameter of an outer peripheral surface around a rotation center axis can be changed. 2. A central axis of rotation; having a hollow cylindrical shape,
It has at least one slit that is arranged concentrically with respect to the rotation center axis and surrounds the outer peripheral surface of the rotation center axis, and extends from one end to the other end in the direction along the rotation center line of the rotation center axis. A blanket cylinder body having a cylindrical blanket on its outer peripheral surface; and a blanket cylinder body supported between the rotation center axis and the rotation center axis interposed between the rotation center axis and the blanket cylinder body;
And a blanket cylinder body diameter changing means for changing a diameter of an outer peripheral surface of the blanket cylinder body with respect to a rotation center line of a rotation center axis. 3. The blanket cylinder body diameter changing means radially extends toward the blanket cylinder body from each of a plurality of positions spaced apart from each other in the circumferential direction of the central axis of rotation, and supports the blanket cylinder body at the extending end. A blanket cylinder main body supporting member that can freely project and retract in the radial direction of the rotation central axis with respect to the rotation central axis; and a projection distance adjusting means that adjusts a projection distance of the blanket cylinder main body supporting member from the rotation central axis in the radial direction. The gapless blanket cylinder according to claim 2, further comprising: 4. A gapless offset printing machine having a gapless blanket cylinder whose diameter of an outer peripheral surface around a rotation center axis can be changed. 5. A plate cylinder in which a plate is wound substantially gaplessly and to which dampening water and ink are supplied from a dampening water means and an inking means, and a cylindrical blanket is put on an outer peripheral surface of the plate cylinder. Winding paper is sandwiched between the blanket cylinder, which contacts and transfers the ink plate image from the plate on the plate cylinder, and the blanket cylinder in cooperation with the blanket cylinder, and rotates in the opposite direction to the blanket cylinder for winding. A plurality of printing units each having at least an impression cylinder for transferring the ink plate image from the blanket cylinder to the winding printing paper while feeding the printing paper and arranged in series in the transport direction of the winding printing paper; Tensioning means for supplying the winding print sheet to the plurality of printing units in a state in which tension is applied to the winding print sheet in the conveying direction; Each of the blanket cylinders of the printing units arranged at least at the second and subsequent positions in the conveying direction of the printing paper has: a rotation center axis; a hollow cylindrical shape, and is arranged concentrically with respect to the rotation center axis to rotate. A blanket cylinder that surrounds the outer peripheral surface of the center shaft and has at least one slit extending from one end to the other end in the direction along the rotation center line of the rotation center shaft, and the outer peripheral surface of which is covered with a cylindrical blanket. The main body; and interposed between the rotation center axis and the blanket cylinder body to support the blanket cylinder body with respect to the rotation center axis,
Blanket cylinder body diameter changing means for changing the diameter of the outer peripheral surface of the blanket cylinder body with respect to the rotation center line of the rotation center axis; and the blanket of each blanket cylinder of the printing units arranged at least after the second. The diameter of the outer peripheral surface of the cylinder main body is set to be larger than the diameter of the outer peripheral surface of the blanket cylinder main body of the blanket cylinder of the printing unit located one upstream side in the transport direction of the rolled printing paper. Gapless offset printing machine using a gapless blanket cylinder. 6. The impression cylinder of each of the plurality of printing units is composed of another blanket cylinder whose outer peripheral surface is covered with a cylindrical blanket, and each of the plurality of printing units includes a plate substantially. And a fountain solution and an ink are supplied from the fountain solution means and the inking means to contact the other blanket cylinder to transfer the ink plate image from the plate to the other blanket cylinder.
The gapless offset printing press using the gapless blanket cylinder according to claim 5, further comprising one plate cylinder. 7. The blanket cylinder body diameter changing means radially extends toward the blanket cylinder body from each of a plurality of positions spaced apart from each other in the circumferential direction of the rotation center axis, and supports the blanket cylinder body at the extending end. A blanket cylinder main body supporting member that can freely project and retract in the radial direction of the rotation central axis with respect to the rotation central axis; and a projection distance adjusting means that adjusts a projection distance of the blanket cylinder main body supporting member from the rotation central axis in the radial direction. A gapless offset printing press using the gapless blanket cylinder according to claim 5 or 6, which is provided.