US1684324A - Register sheet for printing presses and the like - Google Patents

Description

Se pt. 11, 1928. 1,684,324

c. LINGNER REGISTERQSHBET FOR PRINTING PRESSES AND THE LIKE Filed May 16. 1927 N l/EN TOE and Patented Sept. 11, 1928.

UNITED ST'A-lIiES PATENT OF 1 1,684,324 FICE.

oARLLiNennaor DESSAU IN ANHALT, GERMANY, ASSIGNOR To nornuonnanoxnam VON 0.. DUNNHAUET G. M. B. 11,, OF DESSAU, GERMANY.

nnersrrnn snnn'r ron PRINTING rnnssns AND THE LIKE.

Application filed may 1c, 1927, Serial 1101191539, and in Germany November 24, 1925.

Hitherto in printing wor the forms have always been made ready by the-thick places in the register-sheetbeing out out and scraped and by sticking tissue or other paper on the thin places, which frequently entails days of work, where extensive alterations have to be made. Vork of this kind depends upon the skill of the worker.

With the methods and apparatus according to the present invention the forms can be made ready in less time and more accurately, without any particular skill being required on the part of the worker.

The present invention consists in a method,

' the characteristic feature of: which is that the impression made on a printing press or the like as sharply as possible and withmuch sha'ding is stretched with its front side on a plate, all the. raised places on the back ground off and finally the weak places treated by spraying on a self-hardening adhesive.

The adhesive may be sprayed on by means of an atomizer andbe dusted with a powder which hardens rapidly on the heated plate, on which the sheet is stretched, or a self harden ing adhesive liquid may be used.

The register-sheet may also be made of paper to which a magnetizable substance, such as iron, nickel or other suitable material, is added, in finely granular or powdery form, so that the register-sheet will be attracted by a magnet, the plate, on which the register-sheet is laid, acting as the magnet.

In the accompanying drawing a constructional example of the invention in shown. It represents a machine for carrying out the'new method,

Figure 1 being a side elevation, and

Figure 2 a plan View.

The bed plate a which is preferably electrically heated and on which the register-sheet is laid face down and stretched, is guided by planed ribs 6 between similarly planed guides 0 which are fixed to the transverse members cl of the frame e of the machine. The plate a,

cal heatin device, to which current is sup plied thro gh the cable 71. The plate a is provided with two small handles 70 and a. large handle Z, by means of which it is placed inthe machine and can be pushed to and fro.

In the center of the machine a roller m is journalled in pedestals n so as to be capable of being raised and lowered, the cylindrical surface of the roller being provided with an abradant covering.

The roller m is rotated at a high speed by an electric motor '0. If the roller m be lowered to such an extent that it comes in contact with the impression stretched on the plate a and previously treated by the method above described and if the plate a be pushed to and fro under the roller by means of the handle Z, the raised places of the same will be'ground off, an even surface being thus produced.

A brush 79 parallel to the roller m can be placed against the latter for removing the paper dust from it. The brush p is preferably enclosed in a sheet metal casing 9 connected to an exhaust fan, for catching the dust and removing it by suction. The brush 3)- can be put into and out of operation from where the-operator stands by means of a lever r, the bar 8 and thehandlet. The brush might also be in the form of a revolving brush rotatedat a high speed by the-electric motor.

When the register-sheet has been dealt with on the machine just described, so that all the raised places in the sheet have been ground off, anadl-Iesive'liquid, for instance a. gum solution, is sprayedas required on to the weak places of the register-sheet by means of an atomizer, a powder, for instance borax, dextrine or rosin, being strewed on to it, whereupon the sheet is removed from the hot plate after the powder has become hard. l/Vhenthe second-register-sheet is taken, the method described is repeated if required.

As the grinding or milling off of the raised places on the register-sheet does not take as long as the subsequent spraying and heating of the weak places of the register-sheet, if this should be'nece'ssary, the method may be carried' out in separate operations, such that one machine is used for grinding and milling and another or several other machines for the spraying and heating operation.

The method is still simpler, if a selfhardening adhesive be used in place of the adhesive sprayed on by an atomizer, for instance a mixture of dext-rine, gum arabic and alcohol. The important requirement, thatv the sheet should be held firmly over its entire' surface on the supporting plate so that it rests evenly on the same without being at all wavy, is provided for by a further modification of the method, the register-sheet used IUD 7 being made of paper, having an admixture of laid on the de-magnetized supporting plate.

Afterthe sheet has been adjusted carefully by its edges the electric current is switched on so that the plate which has become a mag-- net holds the register-sheet firmly over its entire surface without the possibility of any undulations being formed. The types which project too far on the upper surface of the register-sheet can thereupon be round or milled off. For removing the register-sheet from the plate the electric current is switched off. No mechanical means are required for holding the register-sheet in position.

The electric current can be switched on and off by hand or automatically.

Having now described my invention what I claim as new and desire to secure by Letters Patent is i 1. A method of preparing register-sheets; for printing presses and the like, consisting in making an impression in the press, which is as sharp as possible and has much shading, stretching it face down on a flat plate, grinding oil the raisedplaces on the back of the sheet and thereupon treating the weak places byspraying on an adhesive and hardening the same, as and for the purpose set forth.

2. A method of preparing register-sheets for printing presses and the like. consisting in making an impression in the press, which is as sharp as possible and has much shading, stretching it face down on a heated plate, grinding off the raised places on the back of the sheet and thereupon spraying on a rap-- idly hardening adhesive as required on the weak places by means of an atomizer, as and for the purpose set forth. 7

3. A method of preparing register-sheets for printing presses andthe like, consisting in making an impression in the press, which is as sharp as possible and has much shading, stretching it face down on a heated plate,

grinding off the raised places on the back of the sheet, thereupon spraying on a rapidly hardening adhesive as required on the weak places by means of an atomizer, and dusting the sprayed-on adhesive over with a powder, as and for the purpose set forth.

4. The method as claimed in claim 1, and consisting in taking a second register-sheet, treatingany very weakly printing places from the front of the same, that is from the other side, by the spraying on and hardening of an adhesive, the sheet being laid only loosely on the plate, as and for the purpose set forth.

5. A method of preparing register-sheets for printing presses andthe like, consisting in making an impression in the press, which is as sharp as possible and has much shading, on a sheet of paper containing a magnetizable substance, such as iron or nickel dust,stretching the sheet face' down on a magnetic flat plate, grinding off the raised places on the back of the sheet by means of a rotatin roller, and thereupon treating the wee places by spraying on an adhesive and hardening the same, as and for the purpose set forth.

In testimony whereof Iaifix my signature.

, CARL LINGNER.

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