DE1283248B - Wiping device for single and multi-colored steel engraving - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. CL:

B41f

German class: 15 d-21/11

Number:
File number:
Registration date:
Display day:

P 12 83 248.3-27 (S 95227)

January 28, 1965

November 21, 1968

The invention relates to a wiping device for single and multi-colored steel engraving.

Devices of this type are used in particular for exact prints, for example for printing of banknotes and securities.

A cleaning device for the blanket cylinder of offset printing machines is known two closely spaced and directly in contact with the blanket cylinder Brush rollers that rotate in opposite directions in such a way that the bristles are at the point of contact with the cylinder move towards each other.

This cleaning device is connected downstream of the pressure point. With her the at the respective Point of contact with the cylinder, dirt and detergent particles picked up by the brushes thrown towards the adjacent brush roller. Although scrapers are assigned to the brush rollers are, some of the dirt particles are always brought back to the cylinder roller, which ao leads to undesired color mixing.

Next is a regeneration device for Printing suitable metal plates with motorized brushes is known.

The known devices are devices connected downstream of the printing point for regeneration and cleaning of the printing plates.

In contrast, the subject matter of the invention is a device in which the Printing plate is prepared for printing immediately prior to printing; d. h., at which removes the excess ink from the printing plates before printing.

To date, three means have been used to remove excess ink from the printing plates remove:

a) a strip of cloth or paper that rubs against the printing plate;

b) a cylinder that rolls on the master cylinder without friction;

c) a steel scraper.

However, these three means all have the same disadvantage, namely that they push the paint in front of them in front of their point of contact with the main cylinder. This makes mixing of the different colors inevitable. This mixing is more or less significant, depending on how many colors there are and how close the individual colors are are adjacent. The type of color also plays a role, as does the overlapping of different colors Color ranges. This problem is particularly difficult when printing banknotes that do not have any Wiping device for single and multi-colored steel engraving

Applicant:

Societe des Procedes Serge Beaune,

Creteil, Seine (France)

Representative:

Dipl.-Ing. F. Weickmann,

Dipl.-Ing. H. Weickmann

and Dipl.-Phys. Dr. K. Fincke, patent attorneys,

8000 Munich

Named as inventor:
Request not to be named

Claimed priority:

France of January 31, 1964 (962355) -

May have misprints. Therefore, the printing plates have to be completely scratch-free, because no matter what minor scratches would become visible during printing.

The object of the present invention is to create a wiping device with which mixing of colors is avoided.

To solve this problem, the wiper device of the type mentioned is characterized in that that the wiping device has a plurality of frictionlessly rolling against one another, connected one after the other Cylinders, which are arranged from the plate cylinder at a distance, as well as a wiping cylinder, which between the successive cylinders and the plate cylinder is turned on and with elastic over the Resilient radial doctor blades that brush the surface of the printing plates against at least the dye hurls one of the cylinders connected in series.

However, it is not sufficient to wipe off the excess ink from the plate cylinder without mixing; the color must also be passed on without mixing, d. i.e., remove from the radial doctor blades so that the ink is not reapplied to the plate cylinder by the radial squeegee, resulting in impermissible Mixing of colors would lead.

According to the invention, the cylinder with the radial doctor blades therefore runs at a higher rate for this purpose Rotation speed around so that the paint is thrown off by centrifugal force. The color will

809 638/1159

thereby thrown off tangentially by the doctor blades. So that the thrown off color does not appear any collecting element dries, it is through the plurality of cylinders connected in series directed up to a squeegee.

An exemplary embodiment of the invention is illustrated in the following description with reference to the drawing explained.

The figure shows an engraved plate 3, which is known in Way is mounted on emem plate cylinder 9, which rotates about its axis 10.

The wiping device consists essentially of a cylinder 1, which rotates at high speed and has radial blades on its surface.

len 2 made of elastic material, such as plastic, carries, ■:> - ,. _: . ^, - .... - .; _: ---; ■

When the engraved plate 3 loaded with printing material passes the cylinder Γ, the lamellas 2 brush over the plate 3 and loll the dye away from the surface of the plate 3. In view of the high speed of the cylinder 1, the “lamellas 2 hurl the paint that they have doctored against the cylinders 4, 5, 6, 7, which rotate and thereby guide the paint they have picked up to the squeegee 8. -_ ■ -----. . "

The device according to the invention has, inter alia, the following. Advantages:

1. The color can - something especially for monochrome prints matters - again-

- -be obtained without scratching the engraved plates, such as; about by a metallic squeegee.

2. Polychrome printing plates can be pre-cleaned, which gives the polychrome printing a better quality. ~. . ..-, 3. It can οηηξ further several circumferential cylinders provided with elastic squeegees.

Claims (3)

-. '""' Claims: 1. Wiping device for single and multi-colored steel engraving, characterized in that .that the wiping device has a large number of frictionless rolling against each other, successive cylinders (4,5,6,7), which are from the plate cylinder in one Are arranged at a distance, as well as a wiping ___ cylinder (1), which is switched on between the successively connected cylinders (4, 5, 6, 7) and the plate cylinder (9) and with • elastic over the surface of the pressure plates (3) coating, resilient radial doctor blades (2) deü ■ dye against at least one (4) of the. - cylinder switched in unison is spinning. ■ _ ■ _:, -, 2. Wiper device according to claim 1, characterized in that the of the wiping element (1) paint thrown onto the first cylinder (4) over the successively _; Teten cylinder (5, 6,7) to the last. (7) ■ this cylinder is conveyed and lifted there by a collecting doctor blade (8). 3. Wiper device according to claim 1, characterized in that the radial doctor blades (2) supporting wiper cylinder (1) rotates at high speed. ■ ■ ■ "" " Considered publications:
German Auslegeschrift No. 1124 974;
Austrian patent specification No. 152 863. 1 sheet of drawings 809 638/1159 11.68 © Bundesdruckerei Berlin