JPS5944226B2 - Printer - Google Patents

Description

[Detailed description of the invention] This invention relates to a printing press.

In recent years, attempts have been made to put plate-making techniques using lasers into practical use.

This type of laser plate making machine generally includes a reading laser head for plate-making originals and a writing laser head for printing plate masters whose surfaces are coated with oil-sensitive resin, and the reading laser head scans the original to read the contents. The writing laser head, which scans the printing plate in synchronization with the reading laser head, writes this onto the printing plate and makes the plate, and the plate thus created is removed from the plate-making machine and attached to the printing machine for printing. . However, with these types of plates, the plates must be removed from the printing press each time not only when reassembling the entire printing plate or when remaking plates, but also when only a part of the printing plates are being reassembled, and therefore the reassembly work takes a long time. It has various drawbacks, such as being time consuming and extremely inconvenient because even a small portion of the recombination cannot be performed in an emergency. The present invention eliminates the drawbacks of the above-mentioned conventional devices and provides a printing press that incorporates a laser plate-making device so that the contents of the printing plates can be quickly rearranged while the printing plates are mounted on the printing press. This is the purpose.

The present invention will be described with reference to embodiments shown in the drawings.

The printing machine shown in Fig. 1 includes a plate cylinder 2 for mounting a printing plate 1, an impression cylinder 3,
, a printing unit including an ink forming roller 4 and an ink cylinder 5, as well as an erasing device 6 and a laser plate making device 7.
It is equipped with

The printing plate 1 has a so-called saddle shape that is curved in an arc by approximately half the circumference of the printing cylinder 2, and the outer surface of the base material such as aluminum is coated with a suitable oil-sensitive resin. It was formed as follows.

The plate cylinder 2 is equipped with an appropriate member that fixes the two printing plates 1, 1 with a constant tension at positions displaced by 180 degrees from each other, and a member that pivotally supports the plate cylinder 2 is movably attached to the machine frame. Because it is attached, the impression cylinder 3 can be moved while the printing plate 1 is attached during plate making.
It is designed to be displaced to a position away from the The two ink forming rollers 4, 4 move along the circumference of the ink cylinder 5 during plate making and are sufficiently separated from the plate cylinder 2 because their shaft supporting members are movably attached to the machine frame. It's becoming like that.

As shown in FIG. 2, the plate erasing device 6 is equipped with a slide 9 that is slidably mounted along a slide bar 8 provided on the machine frame, and the slide 9VC has a rocking platform 10 parallel to the axis of the plate cylinder 2. At least one of the slide 9 and the swing table 10 extends along the axial direction of the plate cylinder 2 and along its length. is preferred. Each rocking table 10 has a nozzle 12 at its tip.
A saucer 14 with a large number of pipes 13 arranged in parallel at predetermined intervals in the axial direction of the plate cylinder 2, a drying member 15 consisting of a hot wire heater or a hot air outlet, etc., and a drying member 15 made of soft rubber or foam. It is made of rubber, Molton, etc., and swings between a position where it contacts the plate cylinder 2 and absorbs the liquid from the printing plate 1 and a position where it is separated from the plate cylinder 2 and removes the liquid that has been sucked out by an appropriate means. A squeeze roller 16 is attached. A liquid feed hose 17 is attached to the base end of each pipe 13, and the other ends of these liquid feed hoses 17 are connected to various types of erasing liquid sources via connectors, respectively.
By switching these tips, the appropriate liquid can be sprayed from the nozzle 12 to the appropriate location on the printing plate 1, and a liquid return hose 18 for discharging the used liquid is attached to the saucer 14. It is being In this plate erasing device 6, by the function of an appropriate drive member, during printing, the slide 9 is located at the rear position on the left side as shown in FIG. 1, so that it does not interfere with the operation of the inking roller 4, etc. At times, the slide 9 advances to the right and the swing table 10 swings counterclockwise, so that the tray 14 enters the gap between the plate cylinder 2 and the ink cylinder 5, and the nozzle 12 is brought into a predetermined operating position close to the plate cylinder 2.

As shown in FIGS. 3 and 4, the laser plate making device 7 includes a pinion 2 that is supported by a rail 19 provided on the machine frame and extends in the axial direction of the plate cylinder 2, and that is temporarily connected to a rack 20 provided on the rail 19.
It is equipped with a cross beam 23 that can be moved along the rail 19 by driving a shaft 22 having a shaft 22 with a geared motor 1, thereby making it possible to move between a plurality of plate cylinders 2, 2, . . . By engaging the positioning member 24 provided at the end of the cross beam 23 and the tightening member 25 provided at a predetermined position on the rail 19, each plate cylinder 2 is accurately stopped and tightened at a predetermined position. It is becoming more and more like this.

A laser generator 26 is attached to the cross beam 23, and a laser head 28 and its guide 29 are connected to the laser generator 26 via a glass fiber 27 that totally reflects the laser beam along the inner wall and guides it from one end to the other end. is installed.

The laser head 28 is moved at a predetermined speed along the axial direction of the plate cylinder 2 by the action of a driving member provided on a guide 29, and the guide 29 moves the laser head 28
a plate-making position in which the laser head 28 is brought close to the printing plate 1 on the plate cylinder 2; and a retreat position in which the laser head 28 is sufficiently separated from the plate cylinder 2 so that the laser head 28 does not collide with the impression cylinder 3 when moving to another plate cylinder 2. The plate cylinder 2 can be moved to one or several positions in the axial direction of the plate cylinder 2 and fixed at each position. The laser head 2 is attached to the guide 29.
A pulse generator 30 is provided which generates one pulse every time 8 moves 0.017 m. Also attached to the cross beam 23 are a motor 31 capable of switching between high and low speeds and a pulse generator 32 that generates one pulse every time the plate cylinder 2 rotates by 0.01 degree.
2 is also moved to a position where it does not interfere with the movement of another plate cylinder 2. The motor 31 is connected to the plate cylinder 2
When the gear slide member 33 provided at the shaft end of the plate cylinder 2 is in the plate-making position shown in FIG. 4, it is connected to the shaft of the plate cylinder 2 by gear engagement, and the plate cylinder 2 is rotated at 1000 r.m. when irradiated with laser light. p. m
As mentioned above, when applying the developer, etc., 10r. p. When the gear slide member 33 reaches the left printing position, the shaft of the plate cylinder 2 is disconnected from the motor 31 and engaged with the shaft of the impression cylinder 3 by the gear. Further, during printing, a connecting clutch 35 provided between the impression cylinder 3 and the main motor 34 that rotationally drives the impression cylinder 3 and the plate cylinder 2 via the main motor 34 rotates the impression cylinder 3 when the gear slide member 33 is in the plate-making position. This is to ensure that the printing unit except cylinder 2 is separated from the drive source. Next, the operation of the above embodiment will be described.

When interrupting the printing operation and starting the plate-making operation, the connecting clutch 35 is first disengaged, the gear slide member 33 is switched, and the erasing device 6 is brought to the position shown in FIG. 2, and the erasing process is carried out as follows. I do.

The plate cylinder 2 is rotated at a low speed by the motor 31, and erasing liquid is sprayed from the nozzle 12 onto all or a predetermined part of the printing plate 1. After drying this with the drying member 15, excess liquid is removed. is absorbed by the squeezing roller 16. In this way, the surface of the oil-sensitive resin layer of the printing plate 1 is chemically treated and the plate is erased. Subsequently, the laser head 28 of the laser plate-making device 7 is brought to a position close to the plate cylinder 2, and plate-making processing is performed in the following manner.

The motor 31 rotates the plate cylinder 2 at high speed, and moves the laser head 28 in the axial direction of the plate cylinder 2 at a predetermined speed in conjunction with the rotation of the plate cylinder 2, thereby changing the rotation angle of the plate cylinder 2 and the movement of the laser head 28. The distance is indicated by pulses from pulse generators 32 and 30, respectively. On the other hand, the printing plate original is read by a laser reading device or the like and stored in a computer or the like in advance. This memorized content is transferred to the laser generator 26.
is inputted in synchronization with the pulse, and thereby the laser head 28 scans the printing plate 1 and irradiates the printing plate 1 with appropriate laser light, thereby making a plate exactly as the original on the surface of the oil-sensitive resin layer of the printing plate 1. After making the plate in this manner, the plate erasing device 6 and the laser plate making device 7 are returned to their standby positions, the connecting clutch 35 is connected, the gear sliding member 33 is switched, and the printing operation is resumed. The subsequent plate-making work is also performed in the same manner as described above. By the above-mentioned erasing process, printing plate 1
The oil-sensitive resin layer gradually becomes thinner than the initial state when it is applied, and it has a layer of 100
It is possible to reuse the plate by repeating the erasing and plate-making process nearly several times, and by using the laser plate-making process as described above, it is possible to make an extremely fine plate containing about 300 dots per 6.45 cd. The one that does not use 6.45C7
Compared to the fact that the number of dots per 71 is only about 60 to 100, an extremely excellent printed image can be obtained.

It goes without saying that the present invention is not limited to the above-mentioned embodiments, and that various changes and modifications can be made. Since this invention is constructed as described above, it is possible not only to rearrange only a part of the printing plate, but also to rearrange and re-make the entire printing plate while the printing plate is still attached to the printing machine.Moreover, since it is a laser plate-making method, The printing plate rearranging process itself is easy and accurate, and as a result, the time required to rearrange the printing plates can be greatly reduced and rearranged appropriately in an extremely short period of time. It is extremely convenient when applied to printing presses where the content changes from moment to moment, as hot news can be successively inserted into a part of the paper surface during the printing process, and when applied to textile printing presses, for example, it is possible to insert hot news into a part of the paper surface one after another during the printing process. It is possible to easily change all or part of the printing presses, thereby increasing the variety of products and increasing commercial profits. This has excellent effects such as improving printing efficiency since there is no need to pause the process.

[Brief explanation of drawings]

Fig. 1 is a front view showing an embodiment of the printing press of the present invention;
The figure is a front view showing the operating state of the plate erasing device, and FIGS. 3 and 4 are a side view and a plan view showing the operating state of the laser plate making device. 1... Printing plate, 2... Evil limit 6...
・Eliminating device, 7...Luther plate making device, 8...
...Sliding stick, 9...Slide, 10...
Rocking table, 12... Nozzle, 14... Receiver, 15... Drying member, 16... Squeezing roller, 19... Rule, 23... Cross beam, 24... Positioning member, 25... Tightening member, 26... Loser generator, 28...
Rutherhead, 29... Guide, 30, 32...
...Pulse generator, 31...Motor.

Claims (1)

[Claims] 1. In a printing machine equipped with a plate cylinder for mounting a printing plate, the plate surface of the printing plate is formed of an oil-sensitive resin layer, and the machine frame is provided with:
a plate erasing device for chemically treating the oil-sensitive resin layer of the printing plate mounted on the plate cylinder to erase at least a part of the plate prior to plate making; A printing machine characterized by being equipped with a laser plate-making device that irradiates a printing plate with a laser to make a plate. 2. Claim 1, wherein the laser head of the laser plate making device is adapted to move along the axial direction of the plate cylinder.
Printing machines as described in Section. 3. A plurality of plate cylinders are provided, one plate erasing device is provided for each plate cylinder, and the laser plate making device is movable between each plate cylinder along a machine frame, and 3. The printing press according to claim 1, wherein the printing press is configured to stop at a predetermined position for each printing press.