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Publication numberUS2733804 A
Publication typeGrant
Publication dateFeb 7, 1956
Filing dateAug 19, 1952
Publication numberUS 2733804 A, US 2733804A, US-A-2733804, US2733804 A, US2733804A
InventorsPaul P. Wesson
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Rubber keys fob business and office
US 2733804 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)


United States RUBBER KEYS FOR BUSINESS AND @FFICE MACHINES SUCH AS TYPEWRITERS Paul P. Wesson, East Grange, N. .1. Application August 19, 1952, Serial No. 3053M 9 Claims. (Cl. 197-103) deadening the operation of the machine.

I am Well aware that heretofore it has been proposed to use protecting caps for the keys of typewriters and the like. For the most part they are either constructed of metallic parts, including tempered spring steel springs, or the rubber element is held in place by means of metal collars, etc. The latter soon loosen in their grip upon the keys and permit the cap portions to loosen to the point where they become loose or detached from the keys. Also, it has been proposed to use characters upon such caps, but for the most part they are exposed and subject to frictionand wear with the result that sometimes they become indistinguishable. These disadvantages result in loss of operator efficiency in performing the required work with the machine, until necessary repairs or replacements have been made. To obviate these defects 1 propose to provide aflexible and resilient cap for the keys of typewriters and the like, which is free of metallic parts, and in which the character is protected to the extent that the fingers of the operator do not come in contact therewith. Furthermore, the improved protecting cap has an extremely resilient padarrangement for increasing the shock absorbing characteristics thereof.

A further object of" this invention is the provision of an improved shock absorbing and protecting cap for typewriter keys and the like.

A further objectof this invention is the provision of an improved protector cap fortypewriter keys and the like which is relatively economical to construct; requires practically no maintenance, and one which eifectively maintains its proper position upon the typewriter key under hard usage.

Other objects and advantages of this invention will be apparent during the course of the following detailed description.

In the accompanying drawing, forming a part of this specification, and wherein similar reference characters designate corresponding parts throughout the several views:

Fig. 1 is a vertical sectional view taken thru the irnproved protecting cap, showing the same applied to a typewriter key.

Fig. 2 is a cross sectional view taken thru the piece casing portion of the improved cap.

Figs. 3 and 4 are transverse cross sectional Views taken substantially on the respective lines 3-3 and 44 shown in Fig. 1 of the drawing.

Fig. 5 is a side elevation of the sponge rubber cushion used as a part of the key cap construction.

atent Figs. 6 and 7 are plan views of difierent shapes the protector capmay assume in order to suit different shaped keys of machines.

In the drawing, wherein for the purpose of illustration is shown a preferred embodiment of the invention, the letter A may generally designate the improved cap construction. It is adapted for use upon a key B as shown as well as keys of other shapes. The assemblage A preferably includes a one-piece casing over the key B; a character bearing disc D, and a shock absorbing pad E.

The casing structure C is preferably integrally formed of one piece of material. It may be of rubber, natural or synthetic, or any of the plastics which can be formed as flexible, resilient, and durable. It includes a top wall structure Ill, an annular or cylindrical shaped side wall 11 and a lower gripping sleeve portion 12. The chamber formed by the Walls 10, 11 and 12 is sub-divided into an upper compartment 13 and a lower compartment 14 by means of a wedging and retaining flange 15. The'latter annularly extends into the chamber. It normally has a lower horizontal surface 16, paralleling the lower portion of the gripping sleeve, when in its state of repose and not applied to the key. The upper surface 17 of the flange 15 flares convergently downward to an opening 20. The flange 15 has an edge adapted to lie in closeflush contact With the top surface of the head 10 of the key when applied thereto. The sleeve portion 12,has a reduced central opening 25 therein. It is preferably slightly thicker at its gripping portion than the walls 10 and 11, because it must be considerably distended when applied to the key head 10*. Its inner surface is roughened at 26 for effectively gripping the under or side Walls of the key head. The annular side wall 11 of the casing structure C is provided with minute air vents 30 therethrough, between the flange 15 and the wall 10, to permit the casing and porous sponge rubber pad E to have a breather action under operation.

The disc or wafer D conforms to the shape of the typewriter key. It is preferably of flexible resilient rubber or plastic material and has the character 35 designated upon the top surface thereof; preferably in colored contrast, sufiiciently distinct to be instantly visible. This disc D may be convexly rounded 31 118 101) edge, as shown in Fig. 1, to conform to the convex juncture 36 of the walls 119 and 11 of the casing C. The shock absorbing pad E preferably consists of a cylindrical disc of sponge rubber, or some other equally resilient and flexible shock absorbing and sound deadening material. Its shape is generally that shown in the side elevation of Fig. 5; being of uniform thickness throughout and under slight compression when applied in the compartment 13 of the casing C.

Application of the device A upon the typewriter he will be apparent from the drawing. The character bearing disc is first slipped through the openings 25 and 21 into the compartment 13 beneath the wall 151, and there after the sponge rubber cushion E is likewise slipped through said openings and wedged into the compartment 13 above the flange 15. The sleeve portion 12 is then distended and slipped over the head 10 of the typewriter key B; the roughened surfaces 26 gripping the under or side surfaces of the key head 10 and the top surfacing of the key resting immediately beneath and in Contact With the lower surfacing 16 of the retaining flange 15 and the undersurfacing of the cushion E.

It is within the scope of this invention to provide protecting pads and caps shaped other than circular, for instance, the shape designated at A in Fig. 6 or the rectangular shape designated at A in Fig. 7. The casing wall lil is clearly transparent, in order that the character 35 will beclearly visible therethrough. In fact, the entire'casing structure C may be transparent, but if desired 3 the wall itself may only be transparent and the other structure of the casing translucent or opaque. It should be clearly understood that the casing structure C is flexible and resilient, as is also the character bearing disc D.

However, the shock absorbing pad is much more flexible, pliable and resilient, .the comparison being that of ordinary resilient rubber and sponge rubber as it is known in the art. 7

It will readily be apparent that the operators fingers will not come in contact with any metal or projecting parts. Even. the edging at the top of the cap is rounded. The breather action of the cap enables the sponge rubber pad to respond readily, and thus reduce l finger shock and fatigue. The cap will .not permit a clickingaction to take place between the same and the fingernails of the operator.

Various changes in the shape, size and arrangement of parts may be made to the forin of invention herein shown and described, without departingfrom the spirit of the invention or scope of the claims.

I claim:

1. As an article of manufacture a fatigue resisting, shock absorbing and sound deadening cap for keys of typewriters and the like comprising a flexible casing structure having a chamber therein and a flexible transparent top wall, a yieldable character bearing disc disposed in the chamber immediately beneath the transparent top wall and with the character immediately facing and visible through said top wall, a shock absorbing pad in the chamber beneathsaid disc, and means to connect the casing structure upon the key of a typewriter so that the pad contacts the top of the key.

2. A typewriter key cap as described in claim 1 wherein the casing is provided with vent openings to the chamber thereof to give the same a breather action under impact by the operators fingers.

3. A key cap of the class described comprising a flexible and resilient casing structure having a chamber therein and including a flexible top wall, side walls, and a lower flexible and resilient gripping sleeve, said casing structure above the gripping sleeve havinga flange extending into the chamber spaced from the top wall, and yieldable pad means in said chamber between the top wall and flange, the latter having a tapered slope which the pad engages in order to. compress the outer portion of the pad between the flange and the top wall when the pad is located in said chamber.

4. A cap as defined in claim 3 wherein the casing side walls above said flange are provided with vent openings to give a breather action to the cap under impact by the operators fingers. t

5. As an article of manufacture a completely flexible casing structure for the keys of typewriters comprising a one piece flexible resilient casing having a flexible top wall, flexible side walls, and a lowerflexible clamping sleevehaving a plurality of saw tooth like serrations upon its inner surfacing for the purpose of gripping a typewriter diately adjacent to said pad havingtransverse vent openings therethrough to permit ofa breather action in the chamber of said casing and within the porous sponge rubber pad.

7. In a fatigue resisting and sound deadening protective cap for the keys era typewriter the combination of a flexible and resilient casing structure including a flexible top wall, flexible side walls arranged normal to the plane of the flexible top wall, and a key attaching bottom wall having an opening thereiiffor receiving therethrough the key of a typewriter, said casing structure having a chamber therein adapted t'ofr eceive in the lower part thereof the key of atypewr er', the'u'pper portion-of said chamber above the typewriter keyrece iving portion having transverse dimensions equally as great as the top dimensions of the key portion received in thecasing, and a resilient shock absorbing pad in the upper portion of said chamber below said'flexible top wall of a size to completely cover the top of the key structure received in the lower part of said chamber.

8. i A device as described iii-claim 7 wherein the flexible top wall of said casingstruture is transparent, and a resilient rubber character bea in disc fills said chamber between said shock absorbin'g pad and said top wall.

9. As an article of manufacture a completely flexible casing structure for the keys of ty ewriters comprising a one piece flexible resilient easinghavin'g a flexible top wall, flexible side walls, and a lower flexible clamping sleeve having a plurality of sawtooth like serrations upon its inner surfacing for the purpose of gripping a typewriter key to prevent relative movement of the sleeve upon said key, a retaining flange provided internally of the casing above 'said sleeve and spaced from the top wall, and a compressed shock absorbing pad held between said top wall and said flange. 7

References Cited'in the file of this patent UNITED "STATES PATENTS 552,311 Wolhaupter et a1. Dec. 31, 1895 641,635 Boynton Jan. 16, 1900 971,221 Shepard Sept; 27, 1910 1,087,650 Fox Feb. 17, 1914 1,160,560 Anderson Nov. 16, 1915 2,181,955 Ward Dec. 5, 1939 FOREIGN PATENTS I 345,109 GreatBritain' "Mar.- 19, 1931 369,303 'Great Britaiu 'Mar. 24, ,1932

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US552311 *Sep 14, 1893Dec 31, 1895 W itnesses
US641635 *Apr 21, 1899Jan 16, 1900Frank C BoyntonKey for type-writers.
US971221 *May 28, 1910Sep 27, 1910Harry H ShepardCushion-cap for the keys of writing-machines.
US1087650 *Dec 9, 1911Feb 17, 1914William R FoxKey cap or button for type-writing machines.
US1160560 *Mar 5, 1910Nov 16, 1915Noiseless Typewriter CoKey for type-writing machines.
US2181955 *Mar 7, 1938Dec 5, 1939James P WardFinger key for typewriting and other machines
GB345109A * Title not available
GB369303A * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US5290115 *Sep 17, 1990Mar 1, 1994Little Karen KCushioning means for keyboard keys
US5899616 *Oct 21, 1997May 4, 1999Caplan; Leslie S.Impact absorbing keyboard, contoured to the natural shape of the hand and method of using
US6183149Jan 13, 1999Feb 6, 2001Prosper Street Technologies, L.L.C.Impact absorbing keyboard, contoured to the natural shape of the hand
US7182533May 3, 2000Feb 27, 2007Prosper Street Technologies, LlcKeyboard contoured to the natural shape of the hand
U.S. Classification400/491.1
International ClassificationB41J5/00, B41J5/12
Cooperative ClassificationB41J5/12
European ClassificationB41J5/12