JPH0351594B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention involves attaching a plate-making base paper to a plate cylinder, allowing the ink seeping out from inside the plate cylinder to pass through the plate-making part of the base paper and appearing on the surface, and thereby connecting the plate cylinder and impression cylinder. This invention relates to a plate cylinder for a so-called single-cylinder rotary copying machine, in which printing paper is fed while rotating in close contact, and ink from a plate-making unit is transferred onto the paper for printing.

The plate cylinder of a conventional single-barrel rotary copying machine has ink injected into a hollow cylindrical body consisting only of an outer cylindrical portion, and is naturally absorbed by the capillary action of the screen and the centrifugal force caused by rotation during printing. Alternatively, an outer cylinder and an inner cylinder having a predetermined radial ink gap between the outer cylinder and the inner circumferential surface are installed, and the ink is differentially rotated, and the ink is applied to the outer circumferential surface of the inner cylinder. The ink inside the cylinder was gradually forced into the gap by centrifugal force through a large number of small holes, and the ink oozed out to the surface of the outer cylinder due to the pressure increase caused by the differential rotation.

In the former case, a small amount of ink is injected into a large-capacity cylindrical body and rotated, so the ink is constantly mixed with air and is easily dried and deteriorated, making it impossible for normal leaching to the surface. There was no means to deal with changes in the physical properties of the ink due to temperature changes, and for example, there was no means to compensate for the clay of the ink rising during cold weather and making it difficult to seep into the outer periphery.

In the latter case, the inner and outer cylinders act against each other, and the ink in the ink gap receives shearing force and the pressure increases, allowing the ink to ooze out to the outer periphery without being affected by changes in the physical properties of the ink. When the ink deteriorates in quality, the small holes drilled on the outer periphery often become clogged.Due to the nature of ink being a viscous substance, once the ink has become clogged, the ink no longer leaches out of the hole and the hole is no longer clogged. Naturally, the amount of water leaking out to the outer circumference becomes uneven depending on the location, or there is no leakage at all, making printing impossible. In such cases, it is difficult to disassemble and repair the plate cylinder filled with ink, and the entire plate cylinder must be replaced, which is a heavy economic burden.

SUMMARY OF THE INVENTION The object of the present invention is to provide a novel plate cylinder for a single-barrel rotary copying machine which overcomes the above-mentioned drawbacks.

An embodiment of the configuration of the present invention shown in the drawings will be described.

In the embodiment shown in FIGS. 1 and 2, 4 is an inner cylinder that is loosely fitted onto the plate cylinder shaft 2 so as to be freely rotatable. 9a, 9
Reference numeral b denotes side cylinders, which are provided on both sides of the inner cylinder 4, and are fixed to the plate cylinder shaft 2 so that they can rotate together. A metal mesh that covers the outer periphery of the side barrels 9a and 9b with a predetermined radial ink gap 3 for ink flow between the inner cylinder 4 and the inner cylinder 4;
Alternatively, a metal plate or synthetic resin film is wrapped around and fixed with a net-like body 1a having many small holes, and a cloth screen 1b made of silk, cotton, synthetic resin, etc. is wrapped around the outer periphery of the net-like body 1a.
wrapped around and covered, both of which form an outer cylinder 1,
The joint portion of the screen is held down by a holding plate 11 provided with a base paper holding pin 10.

Both ends of the plate cylinder shaft 2 are supported through frames 12a and 12b, and a sprocket 13 for rotationally driving the plate cylinder is fixed to one end, and a sprocket (not shown) on the motor shaft side, a chain, etc. It is connected with.

A protruding fixed spur gear 14 is provided on the inner surface of the shaft support of the frame 12a, and planetary gears 15a and 15b pivotally supported by the side shell 9a rotate as one.
15a freely moves around the outer periphery of the fixed spur gear 14.

The planetary gear 15b meshes with a spur gear 16 fixed to the side surface of the inner cylinder 4 and is driven.

The ink pump 17 has an ink tank 1 on the suction side.
8. An ink pipe 19 is connected to the discharge side.

The other end of the ink pipe 19 is connected to one end of the plate cylinder shaft 2 by a joint 20 using leakage prevention means.
Furthermore, it communicates with an introduction passage 21 bored in the plate cylinder shaft, and opens at the center of the inner cylinder 4.

Bearings 22a, 2 are mounted on the shaft of the plate cylinder at both ends of the inner cylinder 4.
2b, and oil seals 23a and 23b are inserted therethrough to support the shaft and prevent leakage of the ink that is pumped into the inner cylinder 4.

The interior of the inner cylinder 4 is mostly hollow, but a portion thereof is occupied by an ink supply passage 8 (described in detail below) that communicates with the ink groove 7. The ink supply path 8 starts from an ink supply path front chamber 8a in which the discharge hole of the ink introduction path 21 is open in the center, passes through narrow dispersion gaps 26a and 26b between the apertures 24a and 24b and the dispersion roller 25, and then passes through the ink supply path. It reaches the rear chamber 8b and communicates with the ink groove 7. An inking roller 6 is supported in the ink groove 7 by an inking roller shaft 27 that is parallel to the plate cylinder axis 2, and the outer circumference of the inking roller 6 is in contact with the inner circumferential surface of the mesh body 1a. During the rotation, the roller gap 5 is maintained substantially the same as the ink gap 3.

The dispersion roller 25 is rotated by a dispersion roller gear 29 that meshes with a drive gear 28 fixed to the plate cylinder shaft 2, and an inking roller gear 31 meshes with the inking roller 6 via an idle gear 30. is rotated. This inking roller has a width approximately equal to the printing width.

An impression cylinder 32 is attached to the outer periphery of the outer cylinder 1 so as to be freely rotatable and pressed against the cylinder 32 as the outer cylinder rotates.

In FIG. 2, reference numeral 34 denotes a paper loading table, and a paper feeding rubber roll 35 is provided at the upper front end thereof, and a paper sliding plate 36 and a paper sliding upper plate 37 are opposed to each other in front of the paper feeding rubber roll 35.

A synchronous roll 38 is supported below the paper sliding plate 36, and a synchronous upper roll 39 is supported above the paper sliding upper plate 37 so as to be opposed to each other.

Reference numeral 40 denotes printing paper placed on the paper tray 34.

Since the present invention is configured as described above, when printing paper 40 is placed on the paper tray 34 and the printing is started, the printing paper 40 is fed one by one by the paper feed rubber roll 35, and the synchronous roll 38 , the perforations of the plate-making base paper adhered to the outer periphery of the outer cylinder 1 when it is pressed between the outer cylinder 1 of the plate cylinder 1 and the impression cylinder 32, and are synchronized so that printing is at a fixed position with the synchronous upper roll 39. The printing process is completed by transferring the ink that has appeared from the printing plate and ejecting the paper in a printed state.The plate cylinder, which is the object of the present invention, will be described below.

A fixed spur gear 14 fixed to the frame 12a, and planetary gears 15a and 15b pivotally supported by the side body 9a.
A gear train consisting of spur gears 16 fixed to the side surface of the inner cylinder 4 forms a so-called planetary gear train and differentially rotates the outer cylinder 1 and the inner cylinder 4.

When an amount of ink suitably set to achieve a proper printing density is pumped from the ink pump 17, the ink is ejected through the ink pipe 19, the joint 20, and the introduction path 21, and fills the center of the ink supply path front chamber 8a.

Furthermore, the ink spreads to the left and right while being resisted by the narrow gaps between the dispersion gaps 26a and 26b, and as the dispersion roller 25 slowly rotates, the ink feed path rear chamber 8
be guided by b. From the ink supply path 8b to the ink groove 7
When the ink appears, it is deposited on the inking roller 6, rotates, and is transferred and applied to the inner circumference of the net-like body 1a.

In Fig. 2, the outer periphery of the inking roller 6 is drawn to approach in the opposite direction to the moving direction of the net-like body 1a and transfer ink, but due to the relationship with the porosity of the net-like body 1a, it moves in the same direction. You may get better results by rotating it.

In any case, in order to prevent an excessive increase in pressure in the outer peripheral direction between the inking roller 6 and the mesh body 1a, a roller gap 5 that is substantially the same as the ink gap 3 is provided, and a roller gap 5 is provided that is substantially the same as the ink gap 3. The amount of leaching is naturally obtained in proportion to the amount of ink consumed, which varies depending on the state.

The ink transferred to the inner peripheral surface of the mesh body 1a by the inking roller 6 is sequentially fed into the ink gap 3 by the differential movement between the inner and outer cylinders, and circulates while being given a slight pressure increase due to the differential movement.

In experiments, good results were obtained when the ink gap 3 and the roller gap 5 were both about 0.5 mm to 1.5 mm. It depends on the characteristics of the ink, but if it exceeds 1.5 mm, it will lead to ink transfer.
Circulation becomes difficult. Note that the ink gap 3 and roller gap 5 are both approximately 0.5 mm to 1.5 mm.
If there is a difference between the two gaps, the gaps 3 and 5 can be considered to be substantially the same even if the exact measurement results are different.

The ink appears on the surface layer of the screen 1b due to the weak pressure in the three ink gaps and the capillary action of the screen 1b, and is printed on the printing paper 40 through the perforations of the plate-making base paper attached thereto.

As explained above, in the plate cylinder, ink always fills and passes through a small closed gap, and in between, the dispersion roller 25, the inking roller 6, and the ink gap 3 in a differential state between the inner and outer cylinders. Because it is subjected to a forced kneading action, there is no problem of drying and sticking due to the ink coming into contact with the air, which was a problem in the past, and even if the ink components were to separate, this kneading action Easily mixed and restored by action. Therefore, problems such as partial clogging of ink, which makes it impossible to print, and uneven printing, can be solved. In addition, even if the physical properties of the ink change due to temperature changes, there is a mechanical property in various parts inside the plate cylinder that is proportional to the changes mentioned above (if the clay rises and the degree of leaching decreases, the internal pressure increases and compensates). Since force is applied, problems such as excessive or insufficient printing density or uneven printing density are eliminated. Furthermore, if an inspection port (not shown) is provided at a location other than the printing area of the outer cylinder 1, the ink grooves 7 of the inner cylinder 4 can be easily exposed, and even if the ink solidifies, the plate It is possible to clean the cylinder while it is attached to the machine, and there is no need to replace the entire plate cylinder, significantly reducing maintenance costs. Also, due to the small ink filling amount and the mechanical force, the ink pump 17
There is also the advantage that the ink replenishment operation is very easy to understand because it reacts immediately when activated and prints become darker.

[Brief explanation of drawings]

Fig. 1 is a vertical sectional view of a plate cylinder according to an embodiment of the present invention;
The figure is an explanatory diagram showing the relationship between the center cross section of FIG. 1 and the paper feeding device. 1: Outer cylinder, 1a: Net-like body, 1b: Screen, 2: Plate cylinder axis, 3: Ink gap, 4: Inner cylinder,
5: Roller gap, 6: Inking roller,
7: Ink groove, 8: Ink supply passage, 8a: Ink supply passage front chamber, 8b: Ink supply passage rear chamber, 14: Fixed spur gear, 15a, 15b: Planetary gear, 16: Spur gear, 17: Ink pump, 18: ink tank, 19: ink pipe, 20: joint, 21: introduction path, 24a, 24b: aperture, 25: dispersion roller, 26a, 26b: dispersion gap, 27: inking roller shaft.

Claims (1)

[Claims] 1. An outer cylinder 1 consisting of a net-like body 1a and a screen 1b wrapped around the outer circumference is fixed to a plate cylinder shaft 2 provided with an ink introduction path 21 leading to the inside of the outer cylinder 1, and An inner cylinder 4 having a predetermined radial ink distance 3 with respect to the inner peripheral surface is supported around the plate cylinder axis 2 so as to be differentially movable with respect to the outer cylinder 1, and a part of the inner cylinder 4 is is the introduction path 21
An inking roller 6 is provided with an ink groove 7 that extends from the inner surface of the outer cylinder 1 to the inner surface of the outer cylinder 1.
is pivotally arranged in the ink groove 7 of the inner cylinder 4, and the ink introduction passage 21 and the inking roller 6 are connected so as to have an ink supply passage 8 communicating from the introduction passage 21) to the ink groove 7. A plate cylinder for a single-cylinder rotary copying machine, characterized in that a dispersion roller 25 is provided between the plate cylinders.