JPS6243797Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a water supply device for supplying dampening water in a water tank to a plate surface on a plate cylinder in a lithographic printing press.

A lithographic printing machine is equipped with an inking device that supplies printing ink to the image area of the plate mounted on the plate cylinder, and a damping device to prevent ink from adhering to the non-image area of the plate. A water supply device is provided to supply water to the printing plate.

FIG. 1 is a side view for explaining the outline of this type of water supply device, and to explain this based on the figure, a plate cylinder 1 which is rotatably supported by frames on both sides.
A swimsuit roller 3 is supported by a leveling roller 2 that reciprocates in the axial direction and is in contact with the surface of the printing plate mounted on the circumferential surface of the printing plate. On the other hand, there is a gap between the water base roller 6, which rotates while immersed in the dampening water 5 stored in the water boat 4, and the leveling roller 2.
A transfer roller 7 is provided with both ends supported by a roller arm 9 which is biased with a rotational force in the clockwise direction in the figure by a compression coil spring 8. A cam lever 11 is mounted coaxially with the roller arm 9 and is biased with a rotational force clockwise in the figure by a compression coil spring 10, and a cam follower 12 attached to the free end of the cam lever 11 is It is in contact with a cam surface of a cam 13 that rotates synchronously with the cylinder 1. Then, when the printing operation is started, the dampening water 5 that is rotated by the rotation of the water source roller 6 and adheres to its peripheral surface is transferred to the cam 13.
As the roller arm 9 swings, the image is transferred to the leveling roller 2 by a transfer roller that reciprocates between the rollers 2 and 6, and is supplied to the printing plate via the swimsuit roller 3.

In the water supply device configured in this way, since the dampening water 5 in the water bucket 4 is consumed by supplying the dampening water 5 to the printing plate, this is automatically replenished and the dampening water 5 is also supplied to the printing plate. A forced circulation device for dampening water is often attached to the water boat to serve the purpose of keeping the dampening water warm and purifying it. However, in this type of water boat, the water flows quickly from the water supply port to the drain port in the water boat, and the water level changes or the water surface ripples during this time, causing the water to reach the water head roller 6. The adhesion force became uneven and the quality of printed matter was significantly degraded.

Therefore, in order to eliminate this drawback, a device as shown in FIG. 2 has been proposed. To explain this based on the figure, a water supply pipe 16 is horizontally supported by brackets 15 provided at both ends of the water boat 14, and a supply port 17 is provided at one end of the water boat. A discharge port 18 is attached to the bottom plate of the water boat 14 at an end opposite to the supply port 17 . Further, in one corner of the water boat 14 where the supply port 17 is located, a small chamber surrounding the supply port 17 is separated by an L-shaped partition plate 19, and a water passage hole is provided at the lower end of the partition plate 19. 2
0 is open in two directions. The dampening water supplied by a circulation pump (not shown) passes through the water supply pipe 16 and is discharged from the supply port 17 into the small chamber of the water boat 14, and then enters the water boat 14 from the water passage hole 20 of the partition plate 19. and is discharged from the discharge port 18. The discharged dampening water is purified by a strainer and then returned to the circulation pump for circulation. Note that the water head roller 21 is rotating in the direction shown by arrow A in the figure.

However, in the conventional device configured in this way, the supply port 17 and the discharge port 18 are provided on opposite sides, and by providing a small chamber surrounded by a partition plate 19, the water surface is prevented from undulating on the water supply side. However, this alone cannot be expected to have a satisfactory effect; in particular, it is necessary to prevent the water surface from becoming rippled due to the rapid flow of water in the vicinity of the outlet 18. I couldn't do it. and,
These waves on the water surface directly rush onto the raking part of the water base roller 21, so the amount of water raised by the water base roller 21 varies greatly in the axial direction, as shown by reference numeral 22 in the figure, and this directly affects the surface of the printing plate. As a result, shading occurred in the printed matter, and no improvement in quality could be expected.

The present invention was developed in view of the above points, and includes a partition plate formed in a U-shape and having a lower edge facing the bottom of the water boat on the rising side of the water head roller rotating in the water boat. The water supplied from the water supply port into the small chamber surrounding the water supply port is discharged into the water boat from the water supply port that opens in two directions, and is diffused in each direction to the side where the water source roller starts rotating. By configuring it so that it is guided and discharged from the drain port at the other end of the water boat, the water surface at the raking part of the water base roller is stabilized, the amount of water supplied to the printing plate is uniform, and garbage inside the water boat is removed. The present invention provides a water supply device for a printing press that promotes the discharge of water and improves the quality of printed matter.

Hereinafter, its configuration and the like will be explained in detail with reference to embodiments shown in the drawings.

3 to 5 show the water supply device according to the present invention, FIG. 3 is a perspective view of the water boat and the water head roller, FIG. 4 is a plan view, and FIG. 5 is the same as that of FIG.
It is a BB sectional view. In these figures, inside a water bucket 31 formed in a long rectangular box shape, a water base roller 32 rotating in the direction shown by arrow C in the figure is immersed in dampening water 33 in the water bucket 31 at its lower part. It is mounted on an axis. On the rising side of the rotation of the water head roller 32, there is a surface 34a parallel to the peripheral surface of the water head roller 32 with a sufficient gap therebetween, and a surface 34a parallel to the peripheral surface of the water head roller 32.
A partition plate 34, which is formed into a U-shape in plan view with surfaces 34b and 34c substantially in contact with both end surfaces thereof, is disposed with its lower edge substantially in contact with the bottom surface of the water boat 31. The partition plate 34 is supported by extending the U-shaped portions of a plurality of supports 35 integrally formed on the surface 34a over the water boat 31 and screwing in bolts 36. It is provided to be detachably attached to the water boat 31. Further, a plurality of water holes 37 are provided in the lower part of the partition plate 34 so as to communicate between the inside and outside of the partition plate 34 . That is, a closed water channel 38 is formed between the water base roller 32 and the partition plate 34 and communicates with the outside below the water base roller 32 and through the water passage hole 37 . The water boat 3 is located on the opposite side of the water head roller 32 with respect to the partition plate 34.
A water supply port 41 is opened downward from a water supply pipe 40 supported by a bracket 39 on a water cannon 31 at one of both ends of the water supply pipe 1 . Also,
At the other side end, there is an L-shaped drain port 4.
2 is disposed with its flange fixed to the bottom plate of the water boat 31, and is opened upward at a position higher than the bottom plate. Then, the water supply pipe 40 and the drain port 42
and a circulation pump (not shown) are each connected by a hose. Furthermore, an L-shaped partition plate 43 is provided at one corner of the water boat 31 where the water supply port 41 is located.
A small chamber surrounding the water supply port 41 is separated by the water supply port 41, and a water flow port 44 is opened in two directions at the lower end of the partition plate 43.

The water boat 31 and the water head roller 32 configured as described above are arranged at positions indicated by reference numerals 4 and 6 in FIG. 1, with the water supply pipe 40 and the drain port 42 connected to a circulation pump. Then, when printing work is started and the circulation pump is started, the dampening water 33 is supplied to the water supply pipe 4.
The water is supplied from the water supply port 41 to the small chamber of the water boat 31 through the water supply port 41, and is discharged from the water port of the partition plate 43 to the outside of the small chamber. The discharged dampening water 33 is applied to the surface 3 of the partition plate 34.
Waterway 45 along surface 4a and waterway 4 along surface 34b
It flows into 6 parts and spreads throughout Mizubune 31. Then, the dampening water 33 flowing into the water channels 46 and 47 on the end surface side of the water source roller 32 flows as shown by arrow D in the figure.
After passing over the surfaces 34b and 34c of the partition plate 34, the water flows from below the water head roller 32 into the closed channel 38, that is, the scraping portion of the water head roller 32. On the other hand, a part of the dampening water 33 that has flowed toward the water channel 45 also flows into the closed water channel 38 from the water passage hole 37 . The dampening water 33 thus spread within the water cannon 31 is discharged from the drain port 42 and returned to the circulation pump, after which it is circulated through the aforementioned path. The dampening water 33 in the closed water channel 38 is transferred to the water fountain roller 3 rotating in the direction of arrow C.
2 and adheres to the peripheral surface, and is intermittently scraped up by the leveling roller 2 by the reciprocating transfer roller 7.
After being transferred to the printing cylinder 1 via the swimsuit roller 3
It is supplied to the upper plate.

In the water supply operation performed as described above, a partition plate 34 is placed on the rotation rising side of the water source roller 32.
By providing the water supply port 41 to the drain port 42
Even if waves are generated in the dampening water 33 heading toward the drain or a vortex is generated in the vicinity of the drain port 42 and the water surface is disturbed, the waves and disturbances do not rush toward the raking part of the water source roller 32. In addition, since the dampening water 33 goes around to the back side of the water source roller 32 and flows from below into the raking section, the water surface of the closed channel 38, which is the raking section, is not disturbed and is extremely stable. At the same time, the water level in the axial direction of the water base roller 32 is kept constant.

Furthermore, since the back of the water base roller 32 is open, the water is returned from the water base roller 32 to the water boat 31 from the printing plate through the roller group, and the water is transported to the water base roller 32.
Dust, paper powder, etc. floating on the water surface behind the plate are discharged from the discharge port 42 as the water flows out without going around below the water source roller 32, and are not returned to the printing plate again.

In addition, in this embodiment, an example is shown in which the water passage 37 is provided at the lower part of the partition plate 34, but this is provided to enhance the cooling effect of the dampening water 33. In some cases, it may not be necessary to provide this depending on the water quality, and if the water quality has a particularly slow cooling rate, there may be a slight gap between the end surface of the water source roller 32 and the surfaces 34b and 34c of the partition plate 34. A trowel with a gap is preferable.

As is clear from the above explanation, in the water supply device of a printing press, there is a partition formed in a U-shape and whose lower edge is in contact with the bottom surface of the water bottle on the rising side of the water head roller that rotates in the water bottle. A board is provided, and the water supplied from the water inlet into a small chamber around it is discharged into the water boat from the water inlet that opens in two directions, and is diffused in each direction, to the side where the water source roller starts rotating. By configuring the water boat so that it is guided and discharged from the drain port at the other end of the water boat, even if the water surface is rippled due to the water flow inside the water boat or the vortices near the drain port, this will not reach the raking part of the water head roller. Since it is possible to ensure an extremely stable water surface and water level, the amount of dampening water adhering to the printing plate is averaged to each part, promoting the discharge of dirt, etc. from inside the water tank, and improving the quality of printed matter. can be significantly improved.

[Brief explanation of the drawing]

Fig. 1 is a side view for explaining the outline of the water supply device, Fig. 2 is a perspective view of a conventional water boat and water head roller, and Figs. 3 to 5 show the water supply device of a printing press according to the present invention. 3 is a perspective view showing the water boat and the water head roller, and FIG. 4 is a plan view,
FIG. 5 is a BB sectional view of FIG. 4. 31... Mizifune, 32... Laura Mizumoto, 34...
Partition plate, 34a, 34b, 34c... surface, 41...
... Water supply port, 42 ... Drain port, 43 ... Partition plate, 4
4...Water port.

Claims (1)

[Scope of utility model registration request] A surface 34a parallel to the peripheral surface of the water head roller 32 with a sufficient gap between the rotating start side of the water head roller 32 mounted in the water boat 31, and both end faces of the water head roller 32. A partition plate 34, which is formed into a U-shape in plan view with surfaces 34b and 34c that are substantially attached, is provided with its lower edge substantially attached to the bottom surface of the water boat 31, and the partition plate 34 is provided at both side ends of the water boat 31. There is a water supply port 4 on one side of the
1, a drain port 42 is provided on the other side, and around the water supply port 41, a partition plate having a water inlet 44 facing both the end surface side and the circumferential surface side of the water source roller 32. A water supply device for a printing press characterized by having a small chamber surrounded by 43.