US2389499A - Roll for typewriters - Google Patents

Description

INVENTOR Q50/ZA0M, BY

* A7r0/m y R. A. GORDON ROLL FOR TYPEWRITERS Filed Feb. 8, 1943 Nov. 20, 1945.

Patented Nov. 20, 1945 UNITED STATES PATENT OFFICE 4 ROLL FOR. TYPEWRITERS Ronald A. Gordon, New York, N. Y. Application February 8, 1943, Serial No. 475,156

. e 2 Claims.

This application is a continuation-in-part of my patent application, Serial Number 369,792, filed December 12, 1940, for Typewriter platens and means for illuminating same, wherein I disclosed a platen roller formed of translucent plastic material in association with a source of illumination disposed above and slightly to the rear of the platen.

The platen roll of my pending application is satisfactory for the most part. particularly for stenciling operations, but occasionally possesses slight dimensional inaccuracies from process and frequently must be adjusted to extremely fine accuracy relative to other parts of the carriage to prevent slipping between the platen and the paper passing through the machine.

It is the primary object of the present, invention to carry forward my original idea of utilizing Lucite or its equivalent as a material for typewriter platens and. further, to suggest the use of such material for typewriter feed rolls.

Rubber, cork and like materials employed in platens and feed rolls must be replaced a number of times at considerable expense during the life of a typing machine. Moreover, feed rolls of such material require separate internal bearings of harder material to mount them upon their shafts. The material of my invention will easily outlast the machine. It does notwear away or chip, and it is not subject to deterioration by chemical action of inks and cleansing materials.

It has been proposed to substitute glass and metal for conventional platens. Both are too hard, and the glass is frangible. My platen is harder than rubber, but it possesses sufficient resllience to absorb impact of the keys, without damage and with a minimum of noise. In addition, its greater hardness permits many mor legi le carbon copies to be made from each original sheet.

It is another major object of this invention to treat the surfaces of typewriter rolls formed of "Lucite" or equivalent material to impart to them a slight roughness for paper-feeding purposes. This preferably is done while machining them to accurate diameter, platen roll'and the smaller feed rolls.

Another important object of my invention is to eliminate the usual internal bearings with which feed rolls have been equipped in the past. My plastic feed rolls have internal bores within which their supporting shafts are'slidably fitted for direct contact, this being true regardless of whether the rolls rotat with or independently of and it applies to both the the molding tially upon their shafts during operation of the particular typewriter in which they are mounted.

The foregoing and further objects of the present invention will become apparent from a study of the following detailed description when taken in conjunction with the accompanying drawing and the appended claims.

In the drawing:

Figfll represents, partially sectioned and otherwise in front elevation, a typewriter carriage embodying the platen roll and associated feed rolls of the present invention.

Fig. 2 is a cross-sectional view, taken substanthe plane of line 2-2, Fig. 1.

Fig. 3 is a perspective view of one of the feed rollers seen in Figs. 1 and 2.

With continued reference to the drawing,

wherein like characters are employed to designate like parts, the numeral 5 represents a portion of the framework of any conventional type- ,writer carriage, which carriage includes the usual platen shaft 6 having manually operable knobs I attached to its ends.

Upon the shaft 6 is mounted a platen or roll 8 in the form of a solid cylinder having a bore within which the shaft fits rather closely and non-rotatably. This union preferably is made permanent by a pair of end plates 9 which have hubs l0 secured to the shaft by set-screws i2, there being further screws i3 provided to fasten the plates to the ends of the roll. It should be resistance to all inks and cleaning solutions, and

may be cleansed simply by wiping it with a cloth dampened in alcohol. In particular, as compared with the rubber covered rolls of marketed machines, my improved platen is everlasting, it is substantially noiseless when struck by the keys, and it will produce many more and finer legible carbon copies. It has a combined hardness and resilience that obviate puncturing of the paper.

There are some equivalents or near equivalents in the field of chemo-plastics which may be regarded as falling within the scope of the present invention as substitutes for "Lucite," but none of them is quite as satisfactory.

The above described plastic roll is molded substantially to the cross-sectional shape desired in the form of an elongated solid cylinder, which thereafter is cut into suitable lengths. Each direction of the cylinder. This machining operation is very, very important as it imparts a slight roughness or frostiness to the cylindrical surface to just the extent necessary to make the roll grip"- and prevent slipping of'the papers that pass through the typewriter. If examined closely or under magnification, these machining marks appear as a series of very closely spaced spiraling circumferential lines somewhat fragmented, but to the naked eye at a distance, they have the appearance of a continuous frosted surface. Without them the roll would have a smooth or polished surface and be impractical for use as a platen in a conventional typewriting machine.

Below the platen of the machine the carriage supports, fixedly, a conventional rod If that has mounted thereon a pair or more of hubs l5, each having integral therewith some V-shaped'devices I 6 in the form of supporting cradles for a pair of axles ll, one of which carries a plurality of feed rolls l8 and the other of which carries a plurality of similar rolls l9. These rolls may or may not differ in size, depending upon the machine set-up to which they are adapted, but both sets preferably are formed of Lucite. Regardless of size, each roll comprises a cylindrical element that has been molded, bored and then surface-machined to impart to it a paper-gripping function.

The feed rolls l8 and iii are pressed towards the platen roll 8 by two or more coil springs 20 which surround the rod I4 and each, of which has a V-shaped pair of legs 22 that engage the outer sides of the axles I! in such manner as to urge the latter towards the platen roll 8. Except for the feed rolls, per se, all of this is conventional. Both sets of rolls may be otherwise mounted, of the same diameter and actuated by different types of spring mechanisms. However, it should be noted that heretofore the rolls have been made of rubber or cork, and equipped with internal bearings of metal or its equivalent and therefore expensive in construction and subject to costly replacement. The Lucite feed rolls of this invention have the axles Il directly journaled therein, and the material is such as to out-last the machine frictionally engage the upon which it is moimted. As previously stated, their outer cylindrical surfaces are machined in such manner that they per ectly accomplish their paper-feeding function.

There is nothing novel in the sets of spacing collars 23- and 24, utilized to maintain the feed rolls in position axially of their supporting axles. Th numeral is applied in Fig.- 2 to designate a sheet of paper being fed .through my combination of novel rolls, comprising a platen and two sets of feeders, all formed of Lucite or its equivalent.

It may be added here that the Lucite material of the platen roll may be substantially transparent or colored, but that it preferably is translucent so that it can be used for stenciling, in combination with a lamp disposed just above and behind the platen. In such an arrangement, the light rays enter the platen material and are diffused to make the platen g1ow" so that the operator of the machine can readily detect any errors as the typing operation proceeds. This is a distinct and obvious advantage over prior machines.

The machining of the platen and feed rolls, as previously stated, is highly important. However, such rolls are quite adaptable for use as idling ink-transmitting rolls in press-inking operations, and they serve nicely as impression rolls for mimeograph machines, even without the final machining operation.

Numerous obvious changes may be made within the spirit of my invention to cause a departure from the specific disclosure, and therefore, I wish to be limited, as is customary, only by a proper interpretation of the scope of the appended claims.

What is claimed is:

1. The method of producing a roll designed to paper passing through a typewriter, comprising the steps of molding a chemo-plastic substance such as methyl methacrylate to substantially accurate diameter in the form of a cylinder, and subsequently forming the outer surface of said cylinder to exact diameter and roughening its said'outer surface by machining it with circumscribed circumvolutions so closely spaced as to producea fragmented and frosty appearance. I

2. The method of producing a typewriter platen, comprising the steps of forming a relatively hard cylinder from translucent synthetic plastic material, and then imparting to it a. frosty surface appearance by machining it circumferentially from end to end with spiraling circumvolutions so closely spaced as to appear fragmented.

- RONALD A. GORDON.

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