US3596595A

US3596595A - Screen printing machine with magnetic work support

Info

Publication number: US3596595A
Application number: US755543A
Authority: US
Inventors: Peter Zimmer; Willibald Ruckl
Original assignee: Individual
Current assignee: Individual
Priority date: 1967-08-28
Filing date: 1968-08-27
Publication date: 1971-08-03
Anticipated expiration: 1988-08-03
Also published as: GB1238871A; DE1786113A1; CS161081B2

Abstract

A device for the treatment, particularly for the printing, of flat-shaped material which is moved between two working elements exerting a pressure upon each other. One of the working elements, particularly the printing support of a printing form body, contains a magnet body consisting of a plurality of electromagnets whose magnet cores are arranged in one or more lines having preferably axes perpendicular to the flat shaped material to be treated. The magnet cores project into a stable support body directed to the flat-shaped material to be treated, covered, if the case may be, by a thin casing wherein the stable support body is provided with a recess or perforation passing through the line of magnet cores in whose zone the pole faces of the magnet cores end at a distance from the surface of the support body directed to the material to be treated.

Description

United States Patent Inventor Appl. No.

Filed Patented Assignee Priority SCREEN PRINTING MACHINE WITH MAGNETIC WORK SUPPORT 1 Claim, 4 Drawing Figs.

U.S. Cl.

Int. Cl B41! 15/08,

Field o1Search..

120, l24, 123; 1 181B & S; 107/114, 407

References Cited UNITED STATES PATENTS 7/1898 Rouse .4

Peter Zimmer 6330 Engelhardstrasse, Kul'stein Willibald Ruckl, Tirol, both of, Austria 755.543

Aug. 27, 1968 Aug. 3, 1971 said Peter Zimmer, Kufstein, Austria, by said Willibald Ruck] Aug. 28, 1967, Sept. 4, 1967 Austria A7874/67 and A8065/67 B41fl5/18 101/119,

Primary Examiner- Robert E. Pulfrey Assistant Examiner-J. Reed Fisher Anomey-Wenderoth, Lind & Ponack ABSTRACT: A device for the treatment, particularly for the printing, of flat-shaped material which is moved between two working elements exerting a pressure upon each other. One of the working elements, particularly the printing support of a printing form body, contains a magnet body consisting of a plurality of electromagnets whose magnet cores are arranged in one or more lines having preferably axes perpendicular to the flat shaped material to be treated. The magnet cores project into a stable support body directed to the flat-shaped material to be treated, covered, if the case may be, by a thin casing wherein the stable support body is provided with a recess or perforation passing through the line of magnet cores in whose zone the pole faces of the magnet cores end at a distance from the surface of the support body directed to the material to be treated.

PATENTED AUG 3197! mvmoas PETER ZIMME WILLIBALD RUCKL ATTORNEYS SCREEN PRINTING MACHINE WITH MAGNETIC WORK SUPPORT This invention relates to a device for the treatment, especiallv for the printing, of flat-shaped material which is moved between two working elements exerting a pressure upon each other. one of said working elements, especially the printing support of a printing form body containing a magnet body, said magnet body consisting of a plurality of electromagnets whose magnet cores are arranged in one or more lines and have preferably axes perpendicular to the flat-shaped material to be treated. said magnet cores projecting into a stable support body directed to the flat-shaped material to be treated, and, if the case may be, being covered by a thin casing.

Such a device is known e.g. in rotary screen printing machines, the roller or doctor blade provided inside each cylinder screen consisting of magnetizable material and being attracted by the magnet body arranged in the printing support.

The heat development unavoidable during the operation of the different electromagnets of the magnet body results in a certain length extension of the magnet cores, thus causing the pole faces to show up from the stable support body of the printing support. Thus the originally smooth surface of the printing support is disturbed, and this even, if a thin casing, e.g a sliding sheet, is provided over the stable supporting face and the magnet cores. The thin casing is buckled out by the length extension of the magnet cores. A further result of the magnet cores projecting over the surface of the stable support body or of the bucklings of the casing are striplike irregularities in printing, the material to be printed absorbing more color between the magnet cores than in the strongly pressed zones over the magnet cores.

This shortcoming is avoided according to the invention in that the stable support body is provided with a recess or perforation passing over the line of magnet cores in whose zone the pole faces of the magnet cores end in a distance from the surface of the support body directed to the material to be reated Thus the pole faces of the magnet cores are given a distance from the printing zone of the material to be printed. In this zone alterations of length of the magnet cores can take place which do not show disadvantageous effects. The zones of the support body lying in the direction of passage of the material to be printed in front of and behind the recess or perforation of the support body, provide for the necessary firm support of the material to be printed in the printing zone Emb--diments of the invention are hereinafter described more in detail without being limited to them:

FIG I shows a diagram of a screen station of a rotary screen printing machine.

FIG. 2 shows the printing support of the screen station (without sliding sheet).

F IGv 3 is a section through the screen station (along A-B of FIGv 2).

FIG. 4 shows an analogous section of an embodiment according to FIGS. 1 to 3.

In the embodiment according to FIGS. I to 3, a roller 2 of magnetizable material, eg of steel, is arranged inside the screen cylinder 1 of a rotary screen printing machine, said roller pressing the screen cylinder 1 onto the material to be printed 3 and applying the color through the screen openings of the screen cylinder 1 onto the material to be printed while rolling off the screen inwall. The flat-shaped material to be printed 3, e.g. textile material, is transported by the blanket 4.

Under the blanket 4, opposite the screen cylinder 1, a magnet bar is arranged as printing support by which the roller 2 is attracted and which consists of a plurality of electromagnets 5 whose cylindrical magnet cores 6 project into a stable support body 7. The support body 7 is covered by a thin sliding sheet 8. It supports the material 3 with the blanket 4.

Along the line of magnet cores 6 of the electromagnets 5 the support body 7 is provided with a groove 9. The pole faces 10 of the magnet cores 6 end in the basis of the groove 9. Therefore the latter have a distance from the surface of the support body 7 which allows a harmless clearance of motion of the magnet cores 6 owing to the heating during the current passage through the windings of the electromagnets 5. Even if the pole faces 10 show up from the basis of the groove 9, the sliding sheet 8 and the blanket 4 moved over the sliding sheet 8 remains smooth. The pressure given to the material 3 by the magnetic attraction of the roller 2, is regular over the whole width so that a disadvantageous strip formation during the printing operation is avoided. Besides, the sliding sheet 8 can bend through like a spring in the free space formed by the groove 9; thus, despite of the rigid hard roller 2, an elastic pressure is obtained instead of the usually hard pressure, which has a favorable effect on the printing quality.

The function as described remains the same if the sliding sheet 8 is lacking. In this case, the blanket 4 directly springs into the space formed by the groove 9. Said space can be filled up by a material of a solid state, but of compressible and --up to a certain degree elastic behavior (e.g. felt, elastomere, foam material). This material may also serve as protection against corrosion of the magnet cores consisting of soft iron and very sensitive to corrosion. A covering can also be applied to the pole faces as protection against corrosion.

FIG. 4 also illustrates a screen station of a rotary screen printing machine. Inside the screen cylinder 1, the roller 2 of magnetizable material is contained, said roller pressing the screen cylinder I onto the material to be printed 3 and applying the color through the screen openings of the screen cylinder 1 onto the material to be printed 3 during rolling off the screen inwall. The material to be printed 3 is transported by the blanket 4.

According to FIG 4 the printing support has the form of a roller whose casing 8' rotates around a stationary carrier This carrier, like the magnet bar according to FIGS. 1 to 3, is provided with a plurality of electromagnets 5 having magnet cores 6. The magnet cores also project into a stable support body 7' whose surface IS cylindrical. Like in FIGS. 1 to 3, the support body 7 is provided with a groove in whose basis the pole faces 10 of the magnet cores 6 end. As to the function of this groove. we refer to the explanations of the description of FIGS. 1 to 3.

The embodiments as shown and described refer to the application of the measure according to the invention to screen printing machines provided with rotary screens. However. the invention is not limited to this application. The measure according to the invention can also be applied to magnet bars or magnet rollers for flat screen printing machines.

We claim:

1. A device for the printing of flat-shaped material comprising two working elements exerting a pressure upon one another between which said material is passed, one of said working elements forming a printing support containing a magnet body having a plurality of electromagnets having magnet cores, said magnet cores being arranged in series with their axes perpendicular to said flat-shaped material, a stable support body turned toward said flat-shaped material into which said magnet cores project, the other of said working elements forming a squeegee arranged in and engaging in a printing screen said printing screen contacting said material opposite said support body, said printing screen contacting said material opposite said support body, said stable support body having a recess extending over said series of magnet cores so that the pole faces of said magnet cores terminate at a distance from the surface of said support body turned toward said material to be printed, and said surface of the stable support body turned toward the material to be printed being provided with a thin sheet cover capable of being deflected into said recess of said stable support body.