JPS6316522Y2 - - Google Patents

Description

[Detailed explanation of the invention] This invention was designed to minimize the ink supply path of an offset printing machine, but in exchange for this, dampening water travels through the ink supply path and flows back into the ink pan, diluting the ink and making printing impossible. The present invention relates to a device for stably supplying anhydrous ink by overcoming such inconveniences.

Conventionally known offset printing machines have a group of over 10 inking rollers, are large in size and heavy, are expensive to produce, and are troublesome to adjust the amount of ink.

Therefore, the inking roller group was reduced to 1/3 of the conventional one.
If it were possible to reduce the number of inking rollers to 1/4, it would be possible to achieve the long-awaited reduction in size, weight, and cost, but on the other hand, as the inking roll train was simplified and shortened, dampening water would be transmitted through the very small number of inking rollers. There is a concern that the ink will flow into the ink pan.

Water mixed into the ink increases as printing time passes, reducing print density.Furthermore, if water enters the recesses of the mesh roll, the mesh roll, which is originally an ink-friendly material, no longer receives ink. occurs, and eventually printing becomes impossible.

In this way, the benefits of simplifying the ink supply route for offset printing to the utmost are immeasurable, but at the cost of doing so,
This is accompanied by a fatal inconvenience that leads to the inability to print.
Without solving the latter, it is impossible to provide the former to the world.

The purpose of this invention is to solve the problem of water flowing into the ink pan, and to achieve all of the following at once: reduction in size, weight, and cost, the inability to adjust the amount of ink, and a clear print finish. An object of the present invention is to provide an anhydrous ink supply device for use in simplified offset printing.

The structure of the present invention is that by providing a simple ink supply path in which a mesh roll with a doctor blade is installed in the main part, as a compensation, the dampening water is transmitted from the dampening water supply path through the ink supply path and mixed into the ink in the ink pan. Since the water backflow path is opened, the ink regeneration path, that is, the water-containing ink in the ink pan is guided to the dehydration filter to separate and discharge water from the water-containing ink, while the water-free ink from which water has been removed is transferred to the ink pan. The present invention is characterized in that an ink regeneration path for supplying the ink is provided so that anhydrous ink can be constantly and stably supplied to the ink supply path.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure and operation of the present invention will be explained in detail below using specific embodiments and drawings.

In FIG. 3, 4 is a plate cylinder, 5 is a blanket cylinder, 6 is an impression cylinder, 7 is a running paper, 8, 9, 10 and 1
1 is a dampening water system, which is no different from a conventional offset printing unit.

In the present invention, first, as an ink supply system, a mesh roll 16 is interposed between a metal fountain roll 13 that takes out ink from an ink pan 12 and foam rolls 14 and 15 that are in contact with the plate cylinder 4.

Mesh rolls are originally similar to anilox rolls or screened rolls commonly used in flexo printing, and their peripheral surfaces are made of special steel with extremely fine mesh-like concave engravings, such as 250 mesh, carved on the surface. is coated with chrome plating to improve wear resistance, and its circumferential speed rotates counterclockwise in the figure at the same speed as plate cylinder 4, and rotates at approximately 1/20 of the circumferential speed of plate cylinder 4. Ink is supplied from the fountain roll 13.

However, the ink on the mesh roll 16 is removed by the doctor blade 17, which contacts the mesh roll 16 at a position immediately after it contacts the fountain roll 13 at a reverse angle, that is, in an attitude that runs counter to the rotation of the roll 16. All ink except for the ink is scraped off and returned to the ink pan 12, and only the ink in the recesses that has escaped scraping is supplied to the plate cylinder 4 via the foam rolls 14 and 15. Through such cooperative work between the mesh roll 16 and the blade 17, the plate cylinder 4
The ink that reaches the top is spread to a uniform and uniform thickness, and the optimum amount is always supplied, so there is no longer a need for a large number of ink mixing rolls and ink spreading rolls as in the conventional type. Therefore, the number of inking rolls is only 1/3 to 1/4 of the conventional type.

However, with the simplification of the inking roll train, the dampening water system 8,
The water supplied to the plate cylinder 4 from 9, 10 and 11 is
Foam rolls 14 and 15, mesh roll 1
6 and fountain roll 13 into the ink pan 12, thereby diluting the concentration of ink in the ink pan and making a normal and sharp print finish impossible.

Therefore, a gutter 18 provided on one side of the ink pan 12
Water-containing ink drain pipes 19 and 20 are installed downward from the bottom surface of the container, and are passed through a dehydration filter 21.

The dehydration filter has the function of separating water from water-containing ink, and the ink and water separation means include pressure separation means using a pair of gold rolls in contact with each other, water evaporation separation means using heating, etc. The water separated by such a dewatering filter 21 is discharged into a water reservoir 23 through a drain pipe 22.

On the other hand, the pure ink liquid from which water has been removed by the dehydration filter 21, that is, the anhydrous ink, is stored in the ink tank 25 through the other ink storage pipe 24, and the suction pumps 26 and 27
The ink is returned to the ink pan 12 via ink supply pipes 28 and 29 marked with .

In the present invention, as mentioned above, the mesh roll 16 is used in the ink supply path, and the number of rolls can be reduced to 1/3 to 1/4 of the conventional type. After identifying the problem that causes printing to become impossible due to dilution of the ink concentration, dampening water is introduced into the ink pan 12 from the dampening water supply paths 8, 9, 10, 11, 4 through the ink supply paths 13, 16, 14, 15, 4. Surplus water enters and produces water-containing ink. The water-containing ink is guided to a dehydration filter 21 to remove water, and the water-free ink from which water has been removed is re-supplied into the ink pan 12 24, 2.
5, 26, 27, 28, 29, although some untreated surplus water that does not reach the ink pan 12 remains, the backflow surplus water that gradually increases as printing progresses will not enter the ink pan. minutes are now excluded. Therefore, the clarity of the printing is maintained until the end, and printing is guaranteed to be completed within the desired time without reaching the point where printing is impossible, so that the practical operation of simplified offset printing using the mesh roll 16 is facilitated. Commercial operation has become a reality.

The ink concentration is low for offset use, but higher than that for convex wheels, so a plurality of water-containing ink drain pipes 19 and 20 and ink supply pipes 28 and 29 are provided respectively for circulation. It is desirable to keep it in good condition.

[Brief explanation of the drawing]

The drawings illustrate one specific embodiment of the invention.
Fig. 1 is a vertical side view taken along line 1-1 in Fig. 2, Fig. 2 is an explanatory diagram of the proposed device, and Fig. 3 is an explanatory diagram showing a basic arrangement example of an offset printing unit equipped with the proposed device. be. 4...Plate cylinder, 12...Ink pan, 13...Fountain roll, 16...Mesh roll, 1
7...Reverse angle doctor blade, 18
... Gutter, 19 and 20 ... Water-containing ink drain pipe, 21 ... Dehydration filter, 22 ... Drain pipe, 24 ... Ink storage pipe, 25 ... Ink tank, 26 and 27 ... Pump, 28 and 29
...Ink supply pipe.

Claims (1)

[Scope of Claim for Utility Model Registration] An ink supply path in which a mesh roll with a doctor blade is interposed between a fountain roll that takes out ink from an ink pan and a foam roll in contact with a plate cylinder; A backflow path for water that travels through the supply path and mixes with the ink in the ink pan, and a water-containing ink in the ink pan that guides the water-containing ink to a dehydration filter to separate and discharge water from the water-containing ink, and anhydrous ink from which water has been removed. an ink regeneration path for supplying ink to the ink pan; and an anhydrous ink supply device used for simplified offset printing.