US1668194A - Typewriter platen - Google Patents

Description

May 1, 1928. u 1,668,194 c. T. DlcKEY TYPEWRITER PLATEN "Filed June 25l 1923 INVENTR Cl/La .ui/ay ATTORNEY Patented May 1, 19.28.

UNITED STATES CHARLES T. DICKEY, OF ELIZABETH, NEW JERSEY.

TYPEWRITER PLATEN.

Application filed June 25,

The present invention relates to typewriter platens. It is more particularly directed toward theprovision of an improved typewriter pla-ten which will materially reduce the noise produced in the operation of the typewriter and yet be serviceable for a long time.

Much of the noise which is produced by operating a typewriter is brought about by lo the striking of the keys upon the paper held next to the platen, and the source of considerable of this noise is in the platen itself. Various attempts have been made to provide what is termed a noiseless platen, but heretofore these platens have been more or less unsatisfactory in thaty it was impossible to turn out as good copies in manifolding, as on the regular platen. Furthermore, these platens did not stand up as Well in use as the regular platen, and on account of their more rapid deterioration, replacements Were more fre uent.

T e present invention contemplates the provision of a platen which will permit the making of a much better grade of carbon copies than is possible on the fnoiseless platens heretofore in use, and at the same time this invention contemplates the provision of a platen in which'there is a greater degree of deadening the noise than heretofore. The invention also contemplates the provision of a platen of the noiseless type which has a much longer useful life than those heretofore available. I

In the accompanying drawings several embodiments of invention are shown for purposes of illustration, it being understood that the drawings are illustrative of the invention instead of limiting the same.

In these drawings: f y

Fig. 1 is a side view with parts broken away, showing one embodiment of the present invention;

Fig. 2 is a section taken on' the line 2-2 of Fig. 1;

Fig. 3 is a side view, with parts broken away, of another form of the invention;

Fig. 4 is a section taken' on the line 4-4 of Fig. 3'; and

Fig. 5, 6 and 7 are side views illustrating still further modifications of the invention. According to the form of the invention illustrated in Figs. 1 and 2, the laten 10,

which is of the usual exterior con guration,

is made out of two concentric layers of ma- 1923. Serial No. 847,437.

backing for the outside layer is made of such material that it materially deadens the noises which would be produced in its absence. The backing material 12 shown in Figs. 1 and 2 may be composed of ground felt having a small quantity of rubber sufficient to permit vulcanizing.

In making this type of platen, the backing may first be made up in the form of sheet material which is cut to the proper width, then brought around the pole or mandrel and neatly spliced, or this backing material may first be run onto the tubular form. 'lhere is next applied one ply of sheeting or cloth 13 to the outside of the backing 12. This sheeting or cloth is preferably frictioned or impregnated with a coating of rubber so that the parts may be properly united. 0n the outside of this sheeting there is applied a strip of unvulcanized rubber of the proper consistency and constitution, which, when vulcanized, will produce a good writing surface.. 'lhe platen is then vulcanized in the usual manner, the mandrel removed, the platen cut to size and ground to provide a smooth surface and the platen is then in condition to be delivered to the typewriter manufacturer.

The platen shown in Figs. 3 and 4 is similar to the one shown in Figs. 1 and 2, exce t that, instead of using backing having fe t for the purpose of deadening the sound there is used a layer 14 of ground or comminuted cork mixed with a softer rubber. This platen also has the outer surfacing material 11 as before and the intermediate layer of cloth or sheeting. It may be made in substantially the same manner as that described or the platen with the felt backing.

Fig. 5 illustrates a modified form of laten in which a layer of cloth sheeting 15 lias been applied next the mandrel before the backing material 16 is placed thereon. lAccording to this form of the present invention, the surface material 11 is applied directly to the backing materialwithout any intermediate layer of cloth as previously described.

Fig. 6 illustrates a modification accordin to which there is provided two layers o cloth, one layer 17 which is next the man- 11 drel and a layer 18 which is placed like the cloth 13 between the surface material 11 and the backing 19.

1n` Fig. 7 the platen is shown as being made out of the surfacing material 11 and the backing material 2O without an intermediate layer of cloth and without any inside cloth.

For best results, the backing material should be about twice as thick as the facing material, although good results may be obtained by varying to a considerable extent :from these portions. It has been found that platens made up of the backing material either using the ground felt or the ground cork are a considerable improvement. These platens have been found to operate with much less noise and to rovide much better carbon co ies than p atens of the noiseless type eretofore available. In addition to the use of ground cork or ound felt it is also possible to use as a er in the backing material, textile fibres and similar materials, preferably in a ground condition.

These platens can be made to some extent out of materials which might otherwise go to waste. It has been found that ground cork, ground felt, and other ml.- y

terials may be utilized.

What is claimed is: 1. A typewriter comprising, in combination, an inner layer of sound absorbent parouter layer o rubber, the two layers being 4.6

held together by an intermediate rubbercoated fabric layer, said three layers being united into one integral-.mass by vulcanization and said inner layer being of softer rubber than the outer, andl sald outer layer l0 being of a hardness suitable to deliver a proper impression upon being struc-k by type. CHARLES T. DICKEY.

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