JP3434274B2 - Operating method of sheet-fed offset printing press - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for operating a sheet-fed offset printing press. More specifically, the present invention relates to an operation method of a sheet-fed offset printing press in which a swing roller performs a horizontal swing operation. 2. Description of the Related Art Conventionally, in order to level ink on rollers, some ink rollers of an offset printing machine have been driven to swing in the axial direction of the rollers. 2. Description of the Related Art In a multicolor printing sheet-fed offset printing press in which an ink roller is oscillated, printing is generally performed for each color on printing paper supplied from a paper feeding device at each printing station. Each printing station includes an ink supply device, a dampening device for supplying dampening water, and a number of rollers. Some of these rollers are oscillating rollers, and function to level ink in the width direction of the rollers. Many of such swing rollers always swing a fixed amount. However, if the oscillating roller continues to oscillate while the printing is temporarily suspended for some reason, the balance between the ink supply and the ink established on the paper during printing and the ink on each roller will be balanced. It will collapse. In other words, during steady printing, the amount of ink supplied to the printing paper is such that the ink supply is large in the printing part where the ink is transferred to the paper, and the ink supply is small in the part where the ink transferred to the paper is small. And the ink distribution in the axial direction on the roller is not uniform. However,
If the printing press is stopped for any reason, such as an error in sheet position setting, and the swinging roller continues to be driven, the ink distribution on the roller becomes uniform due to the smoothing effect. . Then, when printing is restarted, many waste sheets with printing unevenness appear until the equilibrium state before the printing was stopped is established again. [0004] Recently, in order to reduce such waste paper at the start of printing, there is a printer which starts and stops swinging according to the timing of printing press operation. An example of such an apparatus is the apparatus described in JP-A-11-240139. This device gradually increases the swing of the swing roller, which is initially zero or the minimum amplitude, at the start of printing, and the amplitude of the swing roller becomes the maximum when the inking roller is inserted. become. In addition, Japanese Patent Publication No. 7-102698 discloses a printing machine in which the swinging is started or stopped at the same time when the ink forming roller is removed and loaded. [0005] However, in these prior arts, the timing of starting or stopping the swing is simply synchronized with the insertion of the ink forming roller or the start and stop of printing. Things. According to the study of the present inventors, it has been found that the start and stop timings of driving of the swing roller described in the prior art are not always optimal. That is, an object of the present invention is to provide a method for optimizing the driving of the oscillating roller and minimizing a waste sheet caused by a short stoppage during the operation of the printing press. SUMMARY OF THE INVENTION The present invention relates to a method of operating a sheet-fed offset printing press in which a swinging roller performs a horizontal swinging operation. There is provided a method of operating a sheet-fed offset printing press, comprising the steps of: stopping a traversing operation; and thereafter, after a time interval of 2 to 7 rotations of the plate cylinder, removing the ink forming roller from the plate. . The present invention is also a method of operating a sheet-fed offset printing press in which a swinging roller performs a traversing operation, wherein a step of receiving a print start command is provided, and an ink forming roller is placed on a plate cylinder. A method of operating a sheet-fed offset printing press, comprising the steps of: contacting a plate; and thereafter, after a time interval of 2 to 7 rotations of the plate cylinder, starting a swinging operation of the swing roller. . The present invention also provides a sheet-fed offset printing press on which these operating methods are implemented. The sheet-fed offset printing press to which the method of the present invention is applied includes various types as long as it has a swinging roller capable of turning on and off the swinging motion or changing the amplitude of the swinging motion, and is particularly limited. Not done. Further, in the method of the present invention, the driving method of the swing roller is not particularly limited. For example, as described in Japanese Patent Application Laid-Open
No. 240139 and Japanese Patent Publication No. 7-102698 and Japanese Patent Application No. 2000-041023.
The mechanism described in the above item can be used to perform the swinging operation of the swing roller. FIG. 1 shows an example of a printing station of a sheet-fed offset printing press to which the driving method of a swing roller according to the present invention can be applied. By arranging a plurality of such printing stations 1, a multi-color printing sheet-fed offset printing press as shown in FIG. 2 can be configured. In FIG. 1, each printing station 1
As shown in the figure, a plate cylinder 3, a rubber blanket cylinder 4, and a counter pressure cylinder 5 are provided. Further, each printing station 1
Includes an ink supply system 6 and a dampening system 7.
Such an offset printing press 1 is controlled by an electronic control unit (not shown) including a microprocessor.
The operator can control the printing press via the electronic control device. The electronic control unit controls the printing station 1. Specifically, the electronic control unit controls on / off operations of the plate cylinder 3, the rubber blanket cylinder 4, and the counter pressure cylinder 5, and also controls the ink supply system 6 and the dampening system. 7 is controlled. In FIG. 1, printing ink is stored in an ink container 12 comprising an ink tray 10 and an ink tray roller 11. Ink tray roller 1
A metering device 13 which is arranged in close contact with 1 and has a plurality of adjusting members having a certain width arranged side by side, so that the ink supply amount can be adjusted for each width of the adjusting members. It has become. The oscillating transfer roller 14 transfers the printing ink from the ink tray roller 11 to the first oscillating roller 15 with a different layer thickness in the transverse direction to the printing direction for each width of the individual adjustment member. The ink supply system further includes second, third, and fourth swing rollers 16, 17, 18
And a first inking roller 19 for applying ink to a plate 23 attached to the surface of the plate cylinder 3, and other inking rollers 20, 21, and 22. The dampening system 7 includes a dampening solution container 24 on a tray,
The dampening roller 25 partially touches the water therein. The metering roller 26 is in contact with the dampening solution container 24. The dampening roller 25 and the metering roller 26 can be driven at different speeds, so that the feed amount of dampening water can be changed according to, for example, the rotation speed of the roller group. The above-mentioned electronic control unit controls the entire printing machine during operation of the printing machine including at the time of starting and stopping, and keeps the amount of dampening water at an appropriate level. The ink supply system 6 and the plate 23 are humidified. The electronic control unit controls the roller position, in particular, the contact and retreat of the oscillating rollers 15, 16, 17, and 18, and the distribution of dampening water in each step. When printing is stopped, all rollers 19, 20, 21, 22 and 27 for applying ink and dampening solution are retracted from the plate 23. At the time of restart, the damping roller 27 is brought into contact with the plate 23 by this control device, whereby moisture is supplied to the plate 23 and the ink supply system 6 via the intermediate roller 29. After this preliminary humidification, the swing roller 15,
16, 17, and 18 are brought into contact with the ink plate 23 to perform inking. In the operation of the humidification and the ink supply, the oscillating rollers 15, 16, 17, and 18 make a reciprocating linear movement in the axial direction, so that the profile of the ink supplied from the ink supply device 12 is appropriately leveled. This enables printing without unevenness. The method of the present invention comprises:
The drive of the swing rollers 15, 16, 17, 18 is optimally controlled. While printing is being performed by the offset printing machine, it is necessary to temporarily stop printing for some reason, such as the position of a sheet being shifted. After receiving an instruction to stop printing, the control device starts the cylinder removal and the ink forming roller 1.
An instruction to save 9, 20, 21, and 27 from the plate 23 is issued. According to the present invention, at this time, first, the control device stops the reciprocating linear motion (lateral swing motion) in the axial direction of the oscillating rollers 15, 16, 17, 18 or reduces the amplitude thereof. Then, after waiting for the plate cylinder 3 (plate 23) to make several rotations, preferably 2 to 7 rotations, more preferably 3 to 5 rotations, the cylinder is actually removed, that is, the ink forming roller 19,
20, 20, and 27 (the ink setting roller 27 also functions as a dampening roller) are retracted from the plate 23. This is because the traversing operation is stopped prior to the actual stoppage of printing on paper, so that it is not leveled in the axial direction of the rollers.
This is because the ink is supplied from the ink supply device 12 to the roller group. Therefore, according to the distance on the roller from the ink supply device 12 to the plate 23, how much before the swinging operation of the oscillating rollers 15, 16, 17, and 18 is performed before the punching out and the retracting of the inch setting roller is determined. Preferably, it is determined. Therefore, when the printing is stopped, the surface of the rollers of the roller group, particularly the surfaces of the ink applying rollers 19, 20, 21, and 27, has a profile of the ink film thickness which is not so uniform, so that the printing is restarted. It is possible to reduce the amount of waste paper caused by printing unevenness at the point of time. Further, when printing is started, a worker inserts a cylinder or forms ink rollers 19, 2 by an operator.
An instruction for abutting 0, 21, 27 on plate 23 is issued. In response to this, contact of the ink forming roller is performed according to an instruction from the control device. At this time, after the abutment of the ink forming roller, the oscillating rollers 15, 16, 17, 18 are caused to oscillate by rotating the plate cylinder 3 several times, preferably 2 to 7 times, more preferably 3 to 5 times. Wait for it to spin before starting. Thus, by delaying the start of the oscillating motion of the oscillating rollers 15, 16, 17, and 18 from the cylinder insertion, the profile of the ink film thickness on the rollers smoothed by the transfer between the rollers during the stoppage of printing is oscillated. Unnecessary homogenization due to the oscillating motion of the moving rollers 15, 16, 17, 18 can be prevented, and an appropriate ink film thickness profile can be more quickly established. FIGS. 3 and 4 show an example of the flow of the control procedure of the printing machine according to the method of the present invention. In FIG. 3, when a print start command is input (101), the dampening roller 27 (which also functions as an "inking roller") is turned on at a certain timing according to an instruction from the control device (102). ). Thereafter, with a slight delay, preferably with a delay of about one to two rotations of the plate cylinder 3, the operation of contacting the plate cylinder 3 with the ink forming rollers 19, 20, 21, 27 is performed (103). Thereafter, the oscillating rollers 15, 16, 17 and 18 are turned on at intervals of several rotations of the plate cylinder 3 (104). The swing operation at this time may be increased to the normal operation amplitude at a stretch, or may be gradually increased to the normal amplitude. Further, the amplitude of the horizontal swing operation can be increased from a completely stopped state or an operation state where the amplitude is small to a normal amplitude. Thereafter, the operation of contacting the rubber blanket cylinder 4 with the plate cylinder 3 and the operation of contacting the rubber blanket cylinder 4 with the counter pressure cylinder 5 are performed almost simultaneously at intervals of 1 to 3 rotations of the plate cylinder 3 (105). . Sheet feeding is subsequently started and printing is actually started (10
6). Thereafter, steady operation is performed (107). As shown in FIG. 4, when a print stop command is input (201), the traversing motion of the oscillating rollers 15, 16, 17, 18 is first stopped by an instruction from the control device. Or reduced (20
2). Thereafter, at intervals of several rotations of the plate cylinder 3, preferably at intervals of 3 to 5 rotations, each of the inking rollers 19, 20, 21, 27, the rubber blanket cylinder 4, and the counter pressure cylinder 5 are respectively provided. Is moved to the evacuation position to release the contact (203). At this time, the dampening roller 25 can be stopped at the same time, or the dampening roller 25 can be stopped with a delay of 1 to 3 rotations of the plate cylinder 3. The supply of the sheet is also stopped at the same time (204). According to those who been described above in the methods and apparatus of the present invention, it is possible to appropriately control the swing low La <br/> other lateral swing motion in the sheet-fed offset printing machine . Therefore, when printing is resumed after the interruption, an appropriate ink film thickness profile can be more quickly established, and the amount of waste paper caused by printing unevenness can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view showing the structure of a printing station of a sheet-fed offset printing press to which the method of the present invention can be applied. FIG. 2 is a schematic view showing the structure of a sheet-fed offset printing press to which the method of the present invention can be applied. FIG. 3 is a flowchart showing an operation stop procedure of one embodiment of the method of the present invention. FIG. 4 is a flowchart showing an operation start procedure of an embodiment of the method of the present invention. [Description of Signs] 1 Printing station 2 Multicolor offset printing press 3 Plate cylinder 4 Rubber blanket cylinder 5 Back pressure cylinder 6 Ink supply system 7 Dampening system 10 Ink tray 11 Ink tray roller 12 Ink supply device 13 Metering device 14 Delivery Rollers 15, 16, 17, 18 Swinging rollers 19, 20, 21, 27 Ink setting roller 23 Plate 24 Dampening solution container 25 Dampening roller 26 Metering roller 29 Intermediate roller

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B41F 31/14 B41F 13/00 B41F 33/10

Claims (1)

(57) Patent Claims 1. A dancer roller is a sheet-fed offset press operating method of performing lateral swing operation, the plate cylinder and the step of accepting an instruction to start printing, the inking roller Contact the plate placed on top
After the step, and after a time interval of 2 to 7 rotations of the plate cylinder,
Starting the oscillating operation of the moving roller, performing a printing operation , receiving a command to stop printing, stopping the oscillating operation of the oscillating roller, and thereafter, the plate cylinder rotates 2 to 7 times. Sheet-fed offset printing machines operating method comprising the steps of separating the by whether et Lee <br/> Nki form rollers at time intervals from the plate to.