US1884384A - Typewrting machine - Google Patents

Description

Oct. 25, 1932. G, THOMPSON I 1,884,384

TYPEWRITING MACHINE Filed March 5. 1951 Patented Oct. 25, 1932 UNITED STATES PATENT OFFICE RUSSELL G. THOMPSON, OF ROCHESTER, NEW YORK, ASSIGNOR '10 ELECTROMATIC TYPEWRITERS, INQ, OF ROCHESTER, NEW YORK, A CORPORATION OF NEW YORK TYPEWRITING MACHINE Application filed March 5, 1931. Serial No. 520,222.

This invention relates to improvements in typewriting machines, and particularly to keys for such machines. It is the common practice in mounting the keys on the key levers to form the keys with tapered openings and pressing them into frictional engagement with a projection on the key lever. This practice causes the key to expand more or less and results in breaking the walls of a large number, rendering them useless, since they will not firmly engage the key. It is the object of this invention to provide a key With means for reinforcing its side walls so that it can be pressed'on the key lever without danger of breaking or splitting its side walls.

More specifically, it is the object of this invention to provide a key for t pewriting machines havinga ring embedde in its side so walls for protecting said walls against breakage.

To these and other ends, the invention consists in the construction and arrangement of parts that will appear from the following description when read in conjunction with the accompanying drawing, the novel features being pointed out in the claims following the specification. 1

In the drawing: 7 Fig. lis a side elevation of a typewriter key lever showing a key in vertical section mounted thereon and illustrating one embodiment of the invention;

Fig. 2 is an enlarged vertical section of the 5, key, and

Fig. 3 is an inverted plan View of the same. Referring particularly to the drawing, 1 is a key lever of usual or well known constructionhaving an upwardly projecting arm 2 at D or adjacent its front end, terminating in a lug 3. The front and rear edges 4' and 5 of the lug 3 are inclined upwardly and meet a horizontal edge 6 at their upper ends. At their lower ends, the edges 4 and 5 terminate i in horizontal shoulders.

The key comprising a body portion 7 is cast or molded of suitable material, such as bakelite, of circular form, as shown in Fig. 3, and

enlarged at its top to form a finger piece.

From the circumferehce of the top it tapers the combination of a key lever,

inwardly and downwardly, having a plane surface 8 at its lpwer side. It is formed with an upwardly extending slot 9 from said lower side, said slot being of a breadth substantially equal to the thickness of the material of which the lug 3 is formed. The front and rear walls of the slot are inclined or tapered toward each other so that the opening 9 in the key conforms generally to the shape of the lug 3, although its front and rear walls are somewhat nearer together so that when the key is pressed on the lug, it is permanently secured thereto by its frictional engagement therewith. a

The frictional engagement of the key with the lug, when the key is pressed on the lug, has a tendency to expand the key and often results in breaking or cracking its thinner walls surrounding the opening 9. It is therefore desirable to reinforce the walls of the key, particularly at and adjacent the lower end of the opening 9 where they are weakest and there is greatest liability of breaking. To this end, a ring 10 of suitable material, such as iron or brass, is cast or otherwise secured in the wall of the key and arranged to entirely surround the opening 9 therein. By this arrangement, the ring is substantially concentric with the key so that it serves,

to reinforce the wall of the key around the opening or slot 9.

A key thus constructed may be made at but little extra expense and efliclently reinforces the walls of the key, eliminating possibility of breakage when the key is pressed on the key lever.

Although only one embodiment of the invention is shownand described herein, it will be understood that this application is intended to cover such changes or modifications as come within the spirit of the invention or scope of the following claims.

I claim:

1. In a typewriting machine or the like, a projecting lug on said key lever, a key constructed of frangible material and having an opening therein whereby it is frictionally engaged with said lug when pressed thereon, and a ring embedded in the wall of said key and surroundin said opening for reinforcing the wall 0 said key. 7

2. In a typewritin machine or the like, the combination of a ey lever, a In having tapered sides-0n said key lever, a ey constructed of frangible material and having an opening therein provided with inclined ,walls corresponding to the tapered sides of the lug w ereby it is frictionally engaged with the lug when pressed into engagement therewith, and a ring arranged in said key around said opening for reinforcing its walls.

3. A key for ty writers or the like con strueted of frangi 1e material and comprising a body having a finger'piece at its top and an opening in its bottom, and a reinforc-V ing ring embedded in the material of said body and surrounding the lower end of said opening 4. A key for ty ewriters or the like constructed of frangible material and compris ing a body enlarged at its top to form a finger piece and an opening in its bottom, said opening havin inclined walls, and a reinforcing ring em edded in the material of said body and surroundin said opening.

In witness whereof, I have ereunto signed my name.

RUSSELL G. THOMPSON.

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