JPH02121840A - Multicolor printer - Google Patents

Abstract

PURPOSE:To facilitate the operation of a plate at the time of replacement and to reduce loss sheet at the time of color matching by providing a clutch in an impression cylinder transmission system, and providing a cam to be so engaged or disengaged as to connect the clutch during the contact of the plate of the cylinder with a matter to be printed. CONSTITUTION:A disc 30 is rotated in a direction (c) through a transmission gear 23 to be engaged with a drive gear 3 and a transmission shaft 15, and the cam roller 33 of a ratchet claw 28 rolls on a cam 34. While the zone of the cylinder 8 on which a plate 12 is not mounted is opposed to a matter 5 to be printed, the claw 28 is disengaged from a ratchet gear 27, and a clutch 25 is disengaged. When the start end of the plate 12 is brought into contact with the matter to be printed, the roller 33 is disengaged from a large-diameter part 36 of the cam 34, and the claw 28 is engaged with the gear 27 to engage the clutch 25. Thus, an impression cylinder 4 is rotated to feed the matter to be printed, the plate 12 is brought into contact with the matter to be printed and printed. When it is brought to the end of the plate 12, the claw 28 is disengaged from the gear 27, and the clutch 25 is disengaged. When the plate 12 is replaced, the cylinder 8 is used as it is, the plate 12 is aligned with a reference position to be mounted.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a rotary multicolor printing press used for printing labels and the like.

(Prior art) In a rotary multicolor printing machine such as a label printing machine, an impression cylinder and a drive gear are provided on a drive shaft, and the impression cylinder and drive gear are interlocked with the drive gear via a plate cylinder gear and have the same circumferential speed as the impression cylinder. There is a system in which a plurality of rotating plate cylinders are arranged at equal intervals in the circumferential direction, and a plate attached to each plate cylinder is used to print on the printing material that is wound around the impression cylinder and sent.

Conventionally, in this type of printing machine, a plate is attached to the entire outer periphery of each plate cylinder, and during printing, the impression cylinder and plate cylinder are continuously rotated, and printing is performed while continuously feeding the printing material. be.

(Problems to be Solved by the Invention) Conventionally, since the printing plate is attached to the entire circumference of the printing cylinder, it is necessary to prepare a printing cylinder with a diameter corresponding to each size of the printing plate. Furthermore, if the diameter of the plate cylinder changes, the peripheral speed must be the same as that of the impression cylinder, so it is necessary to replace the plate cylinder gear as well as the plate cylinder gear, and adjust the position of its shaft. Therefore, in label printing and the like where printing of a wide variety of types and small quantities is required, there is a drawback that preparations before starting printing are extremely troublesome.

In addition, in the case of multi-color printing, color matching is adjusted for each plate while the machine is running, but since the printing material is constantly being fed, a considerable amount of printing material is needed to complete the color matching. This had the drawback of producing a large amount of wasted paper.

SUMMARY OF THE INVENTION In view of these conventional problems, an object of the present invention is to provide a multicolor printing press that allows plates to be easily replaced and that produces less paper waste.

(Means for Solving the Problem) As a means for solving the problem, the present invention provides a plate cylinder 8 equipped with a plate cylinder gear 9 that engages with the drive gear 3 on the outer periphery of the drive gear 3 that is linked to a drive source in the circumferential direction. In a multi-color printing machine in which a plurality of plates are arranged at equal intervals on a plate 1, and a printing material 5, which is wound around an impression cylinder 4 and sent, is printed by a plate 12 attached to each plate cylinder 8, each plate cylinder 8 is An impression cylinder transmission system that drives the impression cylinder 4 at the same circumferential speed as each printing cylinder 8, with the same diameter and a printing plate 12 mounted on a part of the outer periphery of each printing cylinder 8 within a certain range from the reference position A. A clutch 25 is provided in the plate 26, and a cam 34 is provided for operating the clutch 25 on and off so that the clutch 25 is connected while the plate 12 of each plate cylinder 8 is in contact with the printing medium 5.

(Function) When the drive shaft 2 is rotated in the direction of the arrow a by the drive source, each plate cylinder 8 is rotated through the plate cylinder gear 9 that meshes with the drive gear 3.
Continuous rotation in the direction of the arrow. On the other hand, the disc 30 rotates in the direction of arrow C via the transmission gear 23 meshing with the drive gear 3 and the transmission shaft 15, and the cam roller 33 of the ratchet pawl 28 moves on the cam 34. Then, while the section C of each plate cylinder 8 where the plate 12 is not attached corresponds to the printing medium 5, the cam roller 33 moves on the large diameter portion 35 of the cam 34, so that the ratchet pawl 28 is moved from the ratchet gear 27. Missing,
Clutch 25 is in a disengaged state. Therefore, the plate cylinder 8
rotates, and the impression cylinder 4 and printing medium 5 remain stationary.

When the starting edge of the plate 12 comes into contact with the printing substrate 5,
The cam roller 33 is disengaged from the large diameter portion 35 of the cam 34, the ratchet pawl 2 engages with the ratchet gear 27, and the clutch 25 is connected. 4 rotates in the direction of the arrow a and feeds the printing material 5. Therefore, the printing plate 12 is wound around the impression cylinder 4 and comes into contact with the printing material 5 that is being fed, and printing 39 is carried out. Then, when the plate 12 reaches the end, the cam roller 33 moves to the cam 34.
The clutch 25 is disengaged and the ratchet pawl 28 is disengaged from the ratchet gear 27.
The impression cylinder 4 and the printing material 5 stop.

Thereafter, by similarly intermittently operating the impression cylinder 4 and the printing material 5, it is possible to intermittently print 39 on the printing material 5 as shown in FIG.

When replacing the plate 12, the plate cylinder 8 can be used as is, and the plate 12 can be mounted in alignment with the reference position A, and there is no need to replace the plate cylinder 8, the plate cylinder gear 9, or any accompanying adjustments. .

Further, even when color matching is performed between the plates, there is a time when the impression cylinder 4 is stopped and the feeding of the printing material 5 is stopped, so that the occurrence of paper waste can be reduced.

(Example) Hereinafter, the present invention will be described in detail with reference to the illustrated example.
In the drawings and FIG. 2, reference numeral 1 denotes a pair of left and right frames, and a drive shaft 2 that rotates in conjunction with a drive source (not shown), such as an electric motor, is mounted in the center of the frame 1. A large-diameter drive gear 3 is fixedly installed on the drive shaft 2, and
An impression cylinder 4 having the same diameter as this is rotatably fitted onto the sleeve. The impression cylinder 4 guides a printing material 5 for labels or the like wound around the impression cylinder 4, and is configured to nip and feed the printing material 5 between a nip roll 6 supported on the frame 1. An impression cylinder gear 7, which is the same as the drive gear 3, is concentrically fixed to one end of the impression cylinder 4.

8 is a plate cylinder, and four plate cylinders 8 having the same diameter are arranged at equal intervals in the circumferential direction on the outer periphery of the drive gear 3 and the impression cylinder 4. Each plate cylinder 8 is fixed to a rotating shaft 10 together with a plate cylinder gear 9, and the rotating shaft 10 is detachably attached to a bearing 11 of the frame 1.The plate cylinder gear 9 is always engaged with the drive gear 3. . As shown in FIGS. 3 and 4, a synthetic resin plate 12 is detachably attached to each plate cylinder 8 using screws 13 or the like so as to extend over a certain range from a reference position A.

The plate 12 may be mounted within a portion of the plate cylinder 8, for example, up to approximately 160° in the circumferential direction from the reference position A. Therefore, within this range, plates 12 of various ignition strengths can be mounted on the plate cylinder 8 in alignment with the reference position A. Reference numeral 14 denotes an inking device, which is provided on the frame 1 in correspondence with each plate cylinder 8 so as to apply ink to each plate 12.

Reference numeral 15 denotes a power transmission shaft installed on the upper part of the frame 1, as shown in FIG.
0, respectively, and the cylindrical shaft 20 is rotatably supported by a bearing 21.
, is rotatably supported by the frame 1 via a bearing case 22. A transmission gear 23 that meshes with the drive gear 3 is disposed on one end of the transmission shaft 15, and an impression cylinder gear 7 is disposed on the cylindrical shaft 20.
Transmission gears 24 that mesh with the transmission shafts 15 and 20 are provided, and a ratchet type clutch 25 is interposed between the transmission shaft 15 and the cylindrical shaft 20.

The transmission gears 23 and 24 are the same as the plate cylinder gear 9, so that the impression cylinder 4 and the plate cylinder 8 can rotate at the same circumferential speed if the clutch 25 is connected. Note that the impression cylinder transmission system 2 is formed by the transmission shaft 15, transmission gears 23, 24, cylinder shaft 20, etc.
6 are configured.

As shown in FIGS. 5 and 6, the clutch 25 includes a ratchet gear 27 fixed to one end of the cylinder shaft 20, and a ratchet pawl 28 that can be freely engaged with and disengaged from the ratchet gear 27. The ratchet pawl 28 is pivotally connected to a disk 30 by a support shaft 29, and is biased toward the ratchet gear 27 by a spring 32 stretched between a spring hook 31 of the disk 30. The disc 30 is fixed to the transmission shaft 15.

The clutch 25 is configured to perform cutting by operating a cam roller 33 provided in the middle of the ratchet pawl 27 with a cam 34. That is, when the cam roller 33 is removed from the large diameter portion 35 of the cam 34, the ratchet pawl 28 engages the ratchet gear 27 and the clutch 25 is connected. This is the section B where the plate 12 of the plate cylinder 8 comes into contact with the substrate 5 to be printed.

The cam 34 consists of a fixed cam 36 fixed to the bearing case 22 and a movable cam 37 whose angle is freely adjustable.
The cutting positions are set respectively. Note that the connection position coincides with the reference position A, and the cutting position changes depending on the size of the plate 12 in the circumferential direction. While the clutch 25 is disengaged, the impression cylinder 4 stops and the printing material 5 is not fed.

The position of each plate cylinder 8 is such that, where the number of plate cylinder gears is nz, the number of driving gears between each plate cylinder gear 9 is %anz (a is a constant).

In the above embodiment, a single-cylinder type with one impression cylinder 4 was exemplified, but as shown in FIG.
This can also be done in the same way with a double-barrel type.

Furthermore, the clutch 25 is not limited to a ratchet type. It is best to use helical tooth gears for each gear.

(Effects of the Invention) According to the present invention, each plate cylinder 8 has the same diameter, and the plate 12 is mounted on a part of the outer periphery of each plate cylinder 8 within a certain range from the reference position i'ZA. A clutch 25 is provided in the impression cylinder transmission system 26 that drives the cylinder 4 at the same circumferential speed as each plate cylinder 8, and is connected so that the clutch 25 is connected while the plate 12 of each plate cylinder 8 is in contact with the printing material 5. Since a cam 34 is provided to operate the clutch 25 on and off, it is very easy to handle when changing plates.
In addition, the occurrence of wasted paper during color matching can be reduced. Furthermore, since the clutch 25 is operated by the cam 34, the structure is simple.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; FIG. 1 is a side view, FIG. 2 is a plan view, FIG. 3 is a perspective view of the plate cylinder, FIG. 4 is an enlarged view of the main part, and FIG. 5 is the impression cylinder. FIG. 6 is a sectional view of the transmission system, FIG. 6 is a sectional view of the clutch, FIG. 7 is a plan view of the printing material, and FIG. 8 is a schematic diagram of the entire system. 3-driving gear, 4-impression cylinder, 5-printing material, 8 plate cylinder,
12-version, 25-clutch, 26... impression cylinder transmission system,
34-Cam, A-Reference position. Sanki Kikai Co., Ltd. Figure 3 @ Figure 2 Figure 6 Figure 1g5 Figure

Claims (6)

[Claims] (1) A plurality of plate cylinders (8) equipped with plate cylinder gears (9) that mesh with the drive gear (3) are arranged at equal intervals in the circumferential direction on the outer periphery of the drive gear (3) that is linked to the drive source. Each plate cylinder (
In a multicolor printing machine that prints using a plate (12) mounted on a plate (8), each plate cylinder (8) has the same diameter, and a reference position is set on a part of the outer periphery of each plate cylinder (8). Mount the plate (12) within a certain range from (A), and move the impression cylinder (4) to each plate cylinder (
A clutch (25) is provided in the impression cylinder transmission system (26) which is driven at the same circumferential speed as the plate cylinder (8), and the clutch (25) ) to connect the clutch (25).
A multicolor printing machine characterized by being equipped with. (2) An impression cylinder (4) is freely rotatably fitted onto the drive shaft (2) to which the drive gear (3) is fixed. 2. The multicolor printing press according to claim 1, wherein the impression cylinder gear (7) of the cylinder transmission system (26) is fixed. (3) The impression cylinder (4) is single, and the plate cylinders (8) are arranged at equal intervals in the circumferential direction around the outer periphery of this impression cylinder (4). multicolor printing machine. (4) The impression cylinder transmission system (26) has a transmission gear (23) that engages with the drive gear (3) at one end of the transmission shaft (15), and an idler that engages with the impression cylinder gear (7) at the other end. Transmission gear (2
4) respectively, a transmission gear (24) and a transmission shaft (15).
3. The multicolor printing press according to claim 2, wherein the printing press is connected and connected by a clutch (25). (5) The multicolor according to claim 1, characterized in that the cam (34) has a fixed cam (36) and a movable cam (37) provided so as to be rotatable in the circumferential direction with respect to the fixed cam (36). Printer. (6) The clutch (25) includes a disc (30) fixed to the transmission shaft (15), a ratchet gear (27) fixed to the transmission gear (24), and a mechanism for engaging and disengaging the ratchet gear (27). A ratchet pawl (2) pivoted on a disc (30)
8) The multicolor printing press according to claim 1, 2, 3, or 4, characterized by comprising: