US2152858A - Typewriting machine - Google Patents

Description

April4, 1939. F. BECKER 2,152,858

TYPEWRITING MACHINE Filed April 9, 1937 2 Sheets-Sheet l Attor y.

F. BECKER April 4, 1939;

TYPEWRITING MACHINE Filed April 9, 1937 2 Sheets-Sheet 2 Attor M Patented Apr. 4, i939 b F CE f y a "millionth" sheet, whichiis usually made-of: I thin and flexible zinc or aluminum,or any suitablelithograph material, is placed in the typewriter, and is fed around the platen and past the I v printing point by the .usuahbottom. feed rolls.- Auxiliary margin rolls atthe delivery side ofthe' platen hold the metal sheet againsttheplaten.

at the-Iineofprinting. The auxiliary rolls are suitable to run onlyoll the margin of the metal multilith sheet, .becausethey must, not "run upon I the inked letters that are typedupon the sheet.

.The sheet tendsflto "straighten and therefore:

bellies out from the platen betweenqthe marginal auxlliaryrolls. This happensxbecause said 'prcs- 15 sure rolls hold the sheet oi'ily'byits side marginsi The sheet bellieslforwardlyfrom the points where each other and from the platen so that the guide itsside margins are gripped by the rolls.. An attempt to position an auxiliary roll at the middle of theplaten to run upon the middle portion'of 20 the. sheet to prevent bulging, will result in a pick up ofsome ink "from the typed charactersthat arerolled past this middle auxiliaryirollo Eventually enough .ink may be pickedup in thiswa'sa so that a' smudgemwi'lhappear uponflthe metal sheet, this smudge beingproduc'ed hythe rollers.

after they have become. inked.- A'smooth auxiliary roll, placedytolguide the middleoi the. sheet; would also tend to slip .upon'the "multilith? sheet and.wouldtend'toscratch'its coating that is re-. :m pellent to reproducing ink.fv a The trouble referredto is greater when the metal sheet;is placed in the machin withits longer side running parallel withtheplaten. The I present invention employs one or more specially e designed non-smudging guides to lightly guide the central portion of thes-heet. 'Iheseguides printing line, and are able to hold the sheet back "well enough to cause itto back solidly'against the platen atthe printingline, eventhough it begins r to separate from the platen'above theprinting 50 line and be low therolls. The toothed roll is not It does not drive the sheet.

a work-sheet feeder.

,It is loose and turnable on the rod. The teeth may be perhaps f an inch wide,. and their" points may be slightly dulled without detracting.

55 from their ability to hold the bulging sheet back appears near to the platen. The sheettends to straighten I out,;however, and springs out from the platen and presses slightly against the points of the guidewheel .so that the wheel is driven by the contacting sheet to turn upon its rod. The spring of l the sheet is weak where it. contacts the toothed guide-wheel, and hence there is. little. pressure upon the pointed wheel so that it cannot takeup ink freelyfrom' thetypeimpressions onthe sheet.

' The sheet is rolled safelyand efliciently through the-machine but the teeth will have no perceptible effect of inkingcor blurring the sheet.

The middle guideroll vmayzhave aplurality ofteeth which have curved or smooth transverse.

sheet-contacting edges of a width preferably less thana single letter-space and being spaced from wheel turns as the. work-sheet feeds whereby the wheel turns without. slipping? relatively to the sheets. 'Ihe rounding ,of the-edges of the teeth and their spacing from the platen areadapted to obtain very light traction on the bulging metal sheet so'that the toothed wheel travelsconcur rently withthe multilith'sheet' as the latter is fed, and noindentations areleft in the multilith sheet, nor does the toothed wheel pick up ink from the I work-sheet, nor is the light coating 0! the multi- V lith sheet mutilated or scratched. Other ;features and advantages will hereinafter y so In the accompanying drawings, Figure l is a perspective View showing a master multilith sheet in printing position. Figure 2 is across-section, taken on Figure 1 l atthe right of the printing point; but enlarged.

I Figure -3 is a plan view; along the line 3-4 of are in the form of peripherallyttoothedwheel; g. Figurel j v One or more of these pointed wheels may be posietio ned at or near the middle ofthe platen; They; in may be upon a rodwhich mayfialso-supporhthe- II aforementioned'marginalrolls. Thediameterofq the toothed wheelor wheels is less than the diameter of the marginal rolls that hold-the sides, of the sheet snugly to the platen. These marginal 45 and middle rolls are some distance above thew {Figure 4is aiplanvlew similar to Figure 3 show- .ing themaster multilithsheettededgewise in the. typewriter; and: two of the improved 'feed'rolls. 40

Figuregdis an enlarged sidevviewofthe im- Drovedfeedroll.

The usual: cylindrical typewriter vplaten H) has axles H mounted in the ends I! of, a platen-carriage which may be one of .the standard lengths.

spring-pressed toward the platen ID at each end, Guide rolls 25 are slidably and rotatably mounted on the bail I3, one on each end, and are the usual soft rubber cylinders. A Duplex master aluminum multilith sheet 26 is guided under the platen I by the customary feed rolls 21, 28, and 29, the latter being mounted in the usual metal guides 30. Scale plates 32 are spaced from the platen ID a bit more than usual andso likewise the ribbon guide 33 which vibrates in front of the printing point a special Duplex paper carbon printing ribbon 34 through which type 35 impress characters 36 on the master multilith sheet 26.

Arms 31 are pivoted on pins 38 mounted on the inner walls of sides l2 of the platen-carriage.

Springs 39 tied to the arms 31 below the pins 38 tend to hold notches 40, formed in the front walls of arms 31, over the bail I3, and so lock the guide rolls 25 firmly down over the edges of the master multilith sheet 26. The printing side of the sheet 26 may be'covered with an ink-repelling coating 42; the sheet 26 may be coated on both sides;

Care must be taken to keep theguide rolls 25 off the printed-characters 36 because the special Duplex paper-carbon ribbon 34 is impregnated with This bulge tends to engage the bail I3 and to cause scratches on the plate 26, mutilating the special ink-repelling coating 42, and so causing spots or blotches on the printed reproductions. This bulge also tends to move the plate '26 at the center away from the platen Hi to leave a space therebetween so that type 35 fail to meet a firm printing surface, a condition fatal to clear and proper impressions on the sheet 26, because the type 35 must emboss the sheet slightly and precisely under definitely set pressure of the type 35. To overcome the above-recited defects a special cen trally apertured guide roll 44, one or more, is rotatably mounted on the bail l3 to engage the printed characters 36, and is held against motion along the bail l3 by a pair of collars 45, each fastened on the bail l3 by a screw 46.- The roll 44 may be made of metal, preferably steel, having a minimum or negligible traction of adhesion for the special Duplex carbon ink, and may have radially disposed a plurality of points", 41, eleven as shown in Figure 5, equidistant from one another and having smooth rounded contacting surfaces, which cause the roll 44to turn concurrently with the sheet 26 as the latter is fed, but

which tend to roll and press down the special carbon ink, but not to pick it up. The circumferential distance between the centers of adjacent "points 4'! may be different from'the distance between the centers of adjacent lines of typecharacters 36. The points 41 may extend par- It will be obvious that in other forms of the invention this difference in diameter may be more, as, for example, in Figure 2. It is also obvious from said Figure 2, that the toothed guide wheel 44 exerts a leverage upon the sheet 26 to bend it to conform with the curvature of the platen at the printing point and that said wheel 44 reacts with less pressure upon the work-sheet than the marginal" guide roll..

- As shown in Figure 4 the master multilith sheet 26 may be fed edgewise over the platen l0 in a wide-carriage machine so that the lines of printing will run up and down. On such carriages two special guide rolls 44 may be used intermediate of the marginal guide rolls 25. See Figure 4.

' Referring to Figure 3 one of the rolls 25 is seetioned to show an interior sleeve 48 centrally grooved to hold a resilient metal collar 49 normally squeezing the rod l3.

Variations may be resorted to within the scope of the invention, and portions of the improvements may be used without others.

Having thus described my invention, I claim:

1. In a typewriter, the combination with a platen, of means to guide a flexible work-sheet past a printing point to be typed thereupon, including, sheet-deflecting means adapted to bear upon marginal portions of the work-sheet at the delivery'side of the platen, and a deflector in the form of a peripherally toothed wheel intermediate the marginal sheet-deflecting means, and cooperative with the marginal sheet-deflecting means to hold said flexible sheet against the platen at the printing line, said marginal and intermediate deflectors being so arranged relatively to eachother and the platen,'that the said intermediate toothed deflector-wheel reacts with less pressure upon the sheet than the marginal sheetdeflecting means.

2'. In a typewriter having a revoluble platen and types movable to a printing point thereagainst, means for guiding a work-sheet at the delivery side'ofthe plate and for holding said sheet against theplaten at the printing line, said means comprising a rod movable 'into and out of operative position, rollers on said rod for urging the work-sheet margins against the platen beyond the printing line, and a toothed wheel on said rod intermediate said rollers and of less diameter than said rollers to contact by its teeth the intermediate portion of the work-sheet and cause it to bear against the platen at the printagainst, meansfor guiding a work-sheet at the delivery side of the platen and for holding said sheet against the'platen at the printing line, a rod extending lengthwise of said platen, sheet-deflecting means supported on said rod and adapted to urge the work-sheet margins against the platen beyond the printing line, and a toothed wheel on said rod intermediate said marginal sheet-deflecting means to contact by its teeth the intermediate portion of the work-sheet, said toothed wheel being of such a diameter as to react with less pressure upon the sheet than the marginal sheetdeflecting means.

FRED BECKER.

CERTIFICATE OF CORRECTION.

Patent No. 2,152,858 I April 1939.

FRED, BECKER It is herenfi certified that error appears inthe printed specification of the above numbered patent requiring correctionas follows: Page 2, second column, line 15, claim 2, for the word "plate" read pla and that the said Letters Patent ehonld be read. with this correction therein that the sane may conformto the record of the case in the Patent Office.

Signed and sealed this 23raaa of may, A; D. 1959.

o Henry Van Arsdale (Seal) Acting Commissioner of Patents.

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