JP4536343B2 - Variable printing machine and plate exchange method for variable printing machine - Google Patents

Description

  The present invention relates to a variable printing machine having a plurality of printing units, and more particularly to a variable printing machine capable of performing plate exchange of each printing unit without stopping the machine and a plate exchange method thereof. is there.

  The variable printing machine includes a printing unit in which a plurality of sets of printing units that are rotationally driven at a constant rotational speed are arranged on a paper travel line, and a sheet with respect to the printing unit on the upstream side and the downstream side of the printing unit. It consists of the intermittent feeding apparatus arrange | positioned so that it may send intermittently (for example, refer patent document 1). In the conventional variable printing press of this type, when changing the printing plate of the printing cylinder, the entire machine is stopped and the paper is removed from the apparatus.

JP 2003-39630 A

  In the conventional variable printing machine, since the machine must be stopped every time the plate is replaced, it takes time to prepare for printing accompanied by plate replacement, and the production efficiency is poor. In addition, by stopping the machine, adjustment printing is required until printing and registration become stable again, which increases the amount of paper loss and further increases the usage of general consumables such as ink. there were.

  The present invention has been made in view of the above, and a variable printing machine and a plate of this variable printing machine that can solve the above-described conventional problems by allowing a plate to be replaced for the next printing during printing. The purpose is to provide an exchange method.

To achieve the above object, a variable printing machine according to claim 1 of the present invention comprises a printing cylinder and an impression cylinder that are in rolling contact with each other, and a peripheral surface of the impression cylinder has a nip surface with respect to a printing plate surface of the printing cylinder. A plurality of sets of printing units provided with a large-diameter portion and a small-diameter portion serving as a nip opening portion with respect to the plate surface of the printing cylinder, and an intermittent feeding device for intermittently running paper between the printing cylinder and the impression cylinder of each printing unit A drive motor that can be individually controlled for rotation is connected to the printing cylinder of each printing unit, and each printing cylinder and impression cylinder are connected via a clutch.

According to a second aspect of the present invention , there is provided a variable printing press plate changing method according to the first aspect of the present invention, in the variable printing press plate changing method using the variable printing press according to the first aspect, in which the printing unit needs to be changed during printing. The impression cylinder clutch is turned off and the impression cylinder is stopped in a state where the small diameter portion faces the paper . Then, the printing cylinder is rotated by the driving motor to change the plate , and then the printing cylinder is rotated by the driving motor. The clutch is turned on again in a state in which the rotation speed is in phase with the other printing units after the printing preparation process for matching the phase with the other printing units is performed.

  According to the present invention, plate replacement of any printing unit of a plurality of sets of printing units can be performed during the printing operation of another printing unit, so that the time required for printing preparation involving plate replacement can be shortened. This can increase production efficiency. Then, the plate can be changed for the next printing without stopping the machine, and the subsequent printing cylinder is driven again in accordance with the phase of the other printing cylinder until the printing and registration are stabilized. The time is shortened and the amount of waste paper is reduced, and the wasteful use of general consumables such as ink can be reduced.

  FIG. 1 shows a main part of a variable printing machine according to the present invention. In the figure, reference numerals 1a, 1b, 1c denote variable printing units arranged in a plurality of sets on a printing unit on a running line of paper 2, Each of the printing units 1a, 1b, and 1c is an offset type, and includes a plate cylinder 3, a blanket cylinder 4 and an impression cylinder 5 which are in contact with each other and rotate in opposite directions. Has been contacted.

  Large diameter portions 3a, 4a, 5a and small diameter portions 3b, 4b, 5b having the same circumference are provided on the peripheral surfaces of the plate cylinder 3, the blanket cylinder 4, and the impression cylinder 5, respectively. The nip portion is formed by rotating around each other, and each small diameter portion is a nip opening portion. The printing plate is mounted on the large diameter portion 3 a of the plate cylinder 3, and the blanket is mounted on the peripheral surface of the large diameter portion of the blanket cylinder 4. In addition, it is good also as a large diameter part by attaching a printing plate and a blanket to a plate cylinder with a circular cross-sectional shape, and a blanket cylinder, and making another part into a small diameter part.

  The sheet 2 passing between the blanket cylinder 4 and the impression cylinder 5 of each printing unit 1a, 1b, 1c is provided on the upstream side and the downstream side thereof, and is synchronously driven by independent drive motors 7a, 7b, respectively. The intermittent feeding devices 6a and 6b are adapted to intermittently travel.

  The printing cylinder 3, the blanket cylinder 4, and the impression cylinder 5 of each printing unit 1 a, 1 b, 1 c are gear-coupled to each other so that each cylinder rotates at a constant speed. Each of the printing units 1a, 1b, 1c is driven by a single drive motor 7c, 7d, 7e. The drive motors 7c to 7e for driving the printing units 1a, 1b, and 1c can be individually controlled for rotation by a control device (not shown).

  The connecting mechanisms of the plate cylinder 3, blanket cylinder 4 and impression cylinder 5 of the printing units 1a, 1b and 1c are as shown in FIG. 2, and the shafts of the cylinders are connected via bearings 8a, 8b and 8c. It is supported by the frame 9. Gears 10 and 11 that mesh with each other are fixed to the shafts of the plate cylinder 3 and the blanket cylinder 4, and a gear 12 that meshes with the gear 11 on the blanket cylinder 4 side is rotatably supported on the shaft of the impression cylinder 5. ing. The gear 12 is detachably coupled to the shaft of the impression cylinder 5 via an electromagnetic clutch 13 supported on the frame 9 side. When the electromagnetic clutch 13 is turned off, the impression cylinder 5 is in a free state and the printing unit is in a resting state. The gears 10 of the plate cylinders 3 of the printing units 1a, 1b, and 1c are meshed with output gears 14 fixed to the output shafts of the drive motors 7a, 7b, and 7c that can be independently controlled.

  In FIG. 1, among the three sets of printing units 1a, 1b, and 1c, for example, the first and second printing units 1a and 1b are in a printing operation, and the third printing unit 1c has its electromagnetic clutch 13 installed. A state is shown in which the cylinder is stopped with the small diameter portion of the impression cylinder 5 facing the blanket cylinder 4 while being turned OFF.

  In this state, the first and second printing units 1a and 1b are synchronously driven by the drive motors 7c and 7d, and the paper 2 is intermittently fed by the intermittent feeding devices 6a and 6b in synchronization therewith. Variable printing is performed on the sheet 2.

  That is, the intermittent feeding devices 6a and 6b are intermittently operated in synchronism with the operation of the printing units 1a and 1b, and the sheet 2 is oriented in the vertical direction of the image printed on the large diameter portion of the blanket cylinder 4 of the printing units 1a and 1b. The paper travels in the forward direction over the length and stops in a state facing the small-diameter portion of the blanket cylinder 4 or travels in the reverse direction, and the paper 2 is intermittently fed. Variable printing is performed by repeatedly printing without generating in the vertical direction.

  At this time, it is possible to replace the plate of the plate cylinder 3 of the printing unit 1c that is not in operation, even though the printing operation is in progress. That is, the small diameter portion 5b of the impression cylinder 5 of the third printing unit 1c is opposed to the blanket cylinder 4 so that the nip is opened with respect to the paper 2, and the electromagnetic clutch is turned off. In this state, the drive motor 7e is slowly driven to replace the plate of the plate cylinder 3. At this time, the sheet 2 is intermittently fed by printing by the other printing units 1a and 1b. However, in the third printing unit 1c, the nip is opened at the small diameter portion 5b of the impression cylinder 5, so this third The plate replacement work of the printing unit 1c does not interfere with the printing operation by the other printing units 1a and 1b.

  After the plate replacement of the third printing unit 1c as described above, the rotational phase of the blanket cylinder 4 is returned to the position where the rotational direction phase with the impression cylinder 5 matches, and the electromagnetic clutch 13 is turned on to turn on the first. The third printing unit 1c is driven in synchronization with the other printing units 1a and 1b.

  At this time, in order to start printing in the third printing unit 1c after the plate replacement, first, another printing is performed by the drive motor 7e with the nip between the impression cylinder 5 and the blanket cylinder 4 opened. A printing preparation process for matching the rotation speed and phase with the units 1a and 1b is performed.

  In the above embodiment, an example of an offset type variable printing machine in which the impression cylinder 5 is in rolling contact with the blanket cylinder 4 that is in rolling contact with the plate cylinder 3 is shown. Needless to say, the present invention can also be applied to a variable printing machine that is not in an offset type, which is in contact with each other.

1 is a schematic configuration explanatory view showing a variable printing machine according to the present invention. FIG. 3 is an explanatory diagram illustrating a structure for connecting a pressure drum in a printing unit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a, 1b, 1c ... Printing unit 2 ... Paper 3 ... Plate cylinder 4 ... Blanket cylinder 5 ... Impression cylinder 6a, 6b ... Intermittent feeding device 7a, 7b, 7c, 7d, 7e ... Drive motor 8a, 8b, 8c ... Bearing 9 ... Frame 10, 11, 12, 14 ... Gear 13 ... Electromagnetic clutch.

Claims (2)

A printing cylinder and an impression cylinder that are in rolling contact with each other, and a large-diameter portion that becomes a nip surface with respect to the printing cylinder plate surface and a small-diameter portion that becomes a nip opening portion with respect to the printing cylinder plate surface are provided on the peripheral surface of the impression cylinder. A plurality of sets of printing units, and an intermittent feeding device that intermittently runs the paper between the printing cylinder and the impression cylinder of each printing unit,
A variable printing machine characterized in that a drive motor individually controlled to rotate is connected to a printing cylinder of each printing unit, and each printing cylinder and an impression cylinder are connected via a clutch. In the method for exchanging plates of a variable printing machine using the variable printing machine according to claim 1,
Turn off the impression cylinder clutch of the printing unit that needs to be replaced during printing, stop the impression cylinder with the small diameter part facing the paper, and then rotate the printing cylinder with the drive motor to change the plate. After that, after performing a printing preparation process in which the rotational speed of the printing cylinder is phase-matched with another printing unit by a drive motor, the clutch is turned on again in a state in phase with the other printing unit. How to change the plate of variable printing machine.

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