JPS5957755A - Dampening device - Google Patents

Abstract

PURPOSE:To provide the titled device capable of selectively and partially adjusting the amount of water to be supplied depend on the deviation of print density of image area and nonimage area by such an arrangement wherein plural nozzles are laterally arranged at a specified interval along the width of a printing plate and the amount of misty water spouted from each nozzle is caused to independently vary. CONSTITUTION:In the vicinity of a part of the outer circumference of a water fountain roller 4, a nozzle mounting member 6 is provided so as to cover substantially the overall width of the roller 4, and spraying nozzles 10 are installed to holes 9b of the central row. Based on information on the amount of ink for each ink key, a printing plate image area meter determines the amount of water required for each nozzle 10, and it is adjusted by an air pressure adjusting valve 15 and a motor 5 and water is sucked up from a water fountain 11 by an air pump 14 and the spraying nozzle 10 spoutes a specified amount of misty water to the surface of the roller 4.

Description

[Detailed Description of the Invention] This invention relates to a dampening device! [! Offset printing (relating to a dampening device for use).

The plate used for offset printing has a lipophilic image area and a hydrophilic non-image area. This is a device that provides water to prevent ink from adhering to the surface of the printer, and is essential for offset printing machines.

In this case, the amount of water supplied to the printing plate is one of the important conditions 1a that influences the quality of printing. First, if the water supply is too high, it will deteriorate the halftone dot shape and cause insufficient t1 degree of ink and insufficient light selection.On the other hand, if the water supply is too low, it will cause the non-image area. The ink also landed on the printing surface (wasted dirt), making it impossible to obtain proper prints.

Since the 4th century, dampening water devices for offset printing presses have been roughly divided into two types: those in which the water supply is continuously reciprocated by a calling roller, and those in which the water supply is continuous, which is called a continuous water supply system. Two types are predominant.

These conventional dampening water devices generally supply water uniformly over the printing plate surface, but for the reasons explained below, stains occur due to insufficient water supply, and a limit water amount is set. It is being done.

In actual printing plates, the entire surface is uniformly balanced, and there are no printed areas or non-printed areas, and there are quite a few parts that are off-centered by 61 degrees. In this case, setting the water amount during printing 11. J', Ejji i', 'fi part, part of the shadow part, 3jV must be adjusted to the part where a large amount of ink is consumed. This is because areas with a large amount of ink tend to get dirty unless more water is applied than areas with a smaller amount of ink.

The problem here is that when water is added to the shadow part of the image area, there is too much water in the highlight area. In other words, in the highlighted areas, the ink transfer is poor and the shape of the fine dots is distorted, resulting in an overall poor quality mark. However, the reality is that printing is performed in this manner, and this is where printing regulators are having difficulty.

Firstly, the opening degree of each ink key on the printing plate image surface,
Nowadays, technology that can preset the size of ink before printing is becoming commonplace, and setting the optimal amount of water for the amount of ink is becoming more and more important for printing waste paper. It is thought that this will be an important and important field for improvement.

The present invention has been made in view of the above-mentioned circumstances, and provides a dampening water device that can partially adjust the water supply according to the uneven density of image areas and non-image areas on the printing plate. The purpose is to

However, according to the present invention, a predetermined distance l in the direction of the printing plate 11;
Q, a plurality of nozzles arranged in parallel, and a ram for supplying water to the nozzles 4. ．． ), 7, a mechanism for changing the supplied water into a spray, and a plurality of mechanisms for changing the amount of atomized water jetted from each nozzle. ;::
7] Common machine (71.ν characteristic is that it is equipped with 14 pieces of dampening water bag 1 piece).

In general, the ink blade that determines the amount of ink for ink fountain sparrows is rl'''j 01111111+i IJ, C
The amount of ink varies depending on the gap between the openings (the opening I between the ink source roll and the blade), but according to the present invention, the amount of ink increases by 1' in the 11] direction of the printing surface! It becomes possible to set an appropriate amount of water for each amount of ink for the sushi sashimi/coin 6/blade.

The invention will now be explained with reference to the illustrated embodiments -C1iR4.

FIG. 1 shows a schematic diagram of an offset printing press, in which an arbitrary number of ink-bearing rolls 2 are arranged so as to be in contact with a plate cylinder I. In FIG.

This ink coat is provided in front of the roll 2, and a swimsuit for supplying water to the plate surface of the plate cylinder J is provided so that the roll 3 has one side in contact with this plate surface. This swimsuit is roll 3
The water roll 4 is placed in contact with the other surface of the water roll 4. The water roll 4 is driven in the direction of the arrow by, for example, a motor 5, and its rotation is controlled. ing.

Near a part of the circumferential surface of the water base roll 4, a nozzle setting member 6 for supplying dampening water having a curved surface that roughly follows the circular arc is provided over almost the entire length of the water base roll 4. . As shown in Figures 2 and 3, this nozzle setting member 6 is a plate-shaped body curved in an approximately arc shape (・l↓゛), and an IJ wide groove 7 is formed inside the nozzle setting member 6. 3 rows of rl thin ++'j 8a+ 8b + 8 in Z
c are provided at equal intervals.

On the other hand, as clearly shown in FIG.
Three rows of holes 9a+ 9b+ consisting of a series of holes spaced apart by
A groove 9c is provided, which overlaps and communicates with the grooves 8a, Rb, and 8c, respectively.

A spray nozzle 10 is inserted into each of the holes 9h in the center row. Each of these spray nozzles JO has 1 mizufune.
One end of the suction via 12 is inserted into the water in the tank, and the other end of the suction via 12 and one end of the air pipe 13 are inserted. The other end of this Air/P Eve 13 is air, ]? An air pressure regulating valve 15 is provided in the middle, which communicates with the air pump and adjusts the amount of spray.

One end of the collection pipe 16 is inserted into the holes in the rows on both sides, 9cK, and the other end is connected to the hole 11 after being combined with each other.
(It is placed on the water boat 11 via the input tube fJ7. A filter J8 is attached to the flk end of this recovery via 6 as necessary, and the collected mist water is filtered into large water droplets. Alternatively, the water may be collected in the water boat 11.

A leveling roll J9 may be disposed so as to be in contact with the surface of the water base roll 4 as shown in the figure, while the surface of the water base roll 4 extends from the nozzle setting member 6 to the swimsuit roll 3. This leveling roll 19 serves to level out the difference in the boundaries of the application area when different amounts of water are sprayed by the six nozzles 0 and applied to the surface of the water base roll 4, To make this more effective, use this leveling roll 1
9 may be added with an action of swinging 1/1.

To explain the operation of this device, for example, a desired amount of water for each spray nozzle 10 is determined based on information about the amount of ink for each ink key on the printing plate picture surface 41'. and regulated by motor 5. Next, in this state, Air i? When the pump 14 is operated, the water in the water boat 11 is sucked up from the suction pipe 12, and a predetermined amount of water is sprayed.
The fat is sprayed from the jet nozzle 10 toward the surface of the water base roll 4.
'do. At this time, the mist water is applied to the surface of the water base roll 4 while spreading somewhat along the grooves 86 in the direction of the lateral force. On the other hand, suction H? The pump 7 is also operated at the same time, and the water source roll 4 is
Excess mist water that was not attached to the surface is in the groove +'la+
e, passes through the recovery Pide 16, and then passes through the filter 18.
At this point, the water is turned into large droplets and collected into the water boat 11.

The surface of the water roll 4 has an attached edge (and the water leveling roll 19
The swimsuit is transferred to the plate cylinder JK via the roll 2 while the boundaries of the water deposited by each spray nozzle 10 are leveled.

J
For example, even if there is a partial imbalance between the I1 part and the non-surface line part of the printing plate, the optimum amount of water b: can be applied to the printing plate using the ink from each ink key - corresponding to the Jul vc pair. As a result, it is possible to perform offset printing with an appropriate η ink density and light spread, and at the same time, it is possible to reduce the amount of 141 printed waste paper.

Furthermore, among the mist water discharged from the spray nozzle 10,
Although a considerable portion remains unattached to the surface of the water base roll 4, as in the second embodiment, the groove fig.
6 and the suction pump 17 to collect the remaining leopard-like water 1゛Now, 1i (-next! 10
(Large) The problem of vomiting water being released into the atmosphere and corroding the main body of the printing press can be famously retaken. 71 years old..., this 9゛ (IJζ For the form of j(';'lh, :(e) for collecting water, you can choose as many as 11 times longer than the ones in the i column. .-Yo 7” 2, ”I Kirisui 1
．． Regarding the adjustment of item 1, in the above embodiment, we have described what is done by adjusting the air pressure regulating valve 15 and the motor 5. Perhaps it would be possible to install a water regulating valve in the middle of the suction pipe.

4I*1 side tar'it+i, r2. +, 1q Fig. 1 shows a dampening water device according to the present invention and 1V=
A diagram schematically showing a series of machine frames y. Fig. 3 is a partially cutaway plan view of the nozzle setting section.

In the figure, 1... plate cylinder, 2... ink stain (1-le, 3
... Swimsuit Keror, 4... Mizumoto Roll 1, 5...
Motor 16...Knoble positioning member, 7...Groove, 8
a.

Rt+ , +'((!-・groove, R n , , 9 k
+, 9 c-hole, 1...Gout 3 nozzle, 11...
・Mizifune, 12... Sucking Baku 0.73... x7 Paide, 14... Air Moromifu 0.1! −・・・Pneumatic pressure;
Circumvalve, 1G...Recovery pipe, 1...Suction bong
7u, F/+...filter, 19...uniform roll.

Claims (1)

[Scope of Claims] (1) A plurality of nozzles arranged in parallel at a predetermined distance of 1 m in the printing plate width direction, an isostructure for supplying water to the nozzles, and a mechanism tfY for converting the supplied water into a spray form. A dampening water bag u0 (2 2. The device according to claim 1, wherein the nozzles are arranged in parallel downstream thereof and include a groove-like nozzle that communicates commonly with a plurality of nozzles. (3) The nozzle comprises a series of parallel spray nozzles and one or more rows of suction nozzles arranged in parallel along the spray nozzles, and the excess floating water of the dripping water discharged from the nozzles is The apparatus according to claim 1, wherein the mist water is collected by activating a suction nozzle. (4) Suction nozzle row is +plt Both 1 of fog nozzle row
1111 has 71-1 and R1 is being placed! Office 5'
``Claim 111, position 11, 311, position 48. (5) Misty water Jun's death, I i!j>Yang 4:''; is equipped with a pneumatic 1i15 regulating valve! An apparatus according to claim 1.