US2223028A - Typewriting machine - Google Patents

Description

NOV. 26,1940. W A DOBSON 2,223,028

TYPEWRITING MACHINE Filed Nov. 18, -1938 INVENToR WML /AM A ZJOSON BY Patented Nov. 26, 1940 AUNITED STATES PATENT OFFICE TYPEWRITIN G MACHINE Application November 18, 1938, Serial No. 241,226

2 Claims.

This invention relates to noise reducing devices for a typewriter or like machine and more particularly to devices of this character for holding a typewriter on its supporting structure.

A general object of the invention is to provide an improved sound dampening foot for the support of a typewriter on a desk or platform to substantially prevent transmission of sound. vibrations via the foot, and thereby appreciably reduce operating noises of the machine.

Another object is to provide an improved typewriter foot for cooperation with means for releasably holding the typewriter in position on a carrying case base member, the foot and the l5 holding means coacting to hold the machine in place ,within the carrying case duringl transit, or while operating the machine on the case member; in the latter use, preventingv the transmission of operating noises to the case member, and

also affording instant detachment of the machine from the case when desired.

A further object is to provide an improved footl on the fore-and-aft plane through the typewriterl and carrying case base, illustrating the front and rear supporting devices in central section.

Figure 3 is an exploded perspective view of the front foot broken away in section, and the foot holding element of the typewriter.

Figure 4 is a perspective view of the rear typewriter holding device illustrating the rear foot in position on the retaining member of the carrying case.

Figure 5 is an exploded perspective view of therear foot and adjacent portion of the typewriter,

and

Figure 6 is a perspective of the rear foot retaining member of the carrying case.

The numeral 'l indicates a typewriter having at its forward portion a pair of front feet 8, and adjacent its rear portion a pair of rear feet 9 restable on a base or carrying case member I0,

the latter having hingedly mounted thereon a cover II, partly shown.

Each of the typewriter feet 8, 9 comprises an upper or body portion I2 which is of a relatively rm, but preferably resilient material. such as vulcanized solid rubber compound, adapted for attachment to the typewriter. The body portion I2 is preferably of rectangular outline in plan and has its bottom recessed at I3, defining a limited marginal area I4 at the bottom of the body portion. A relatively thin layer of sponge rublo ber I5 conforming in outline to the bottom area I4 of the body portion is securely attached theree to as by cementing or by joining the body and layer by vulcanization.

In the embodiment illustrated, the typewriter u includes a mainframe I8, partly shown, which has at its forward portion a pair of horizontal, apertured lugs |9 for support of the pair of front feet 9. Each front foot has formed at the top of its body portion I2 anupstanding shank 29 terminating in a resilient collar 2|, the shank 20 being of a size to i'lt snugly inV the aperture of lug I9, the foot 8 being retained thereon by the collar 2| overlying the lug |9as shown in Figure 2. The shank 29 and collar 2| of the front foot are preferably integral with the body portion I2 and may be formed thereon 'in the process of molding or vulcanizing the foot. The substantially thick section of the body portion I2 renders same relatively rigid and rm, although constructed of rubber, while the thin section of the collar 2| renders same easily flexed to facilitate assemblage. It will thus be seen that the collar 2|, by being flexed or gathered upwardly, may be u constricted to a diameter approximating that of the shank 20 and may thus be inserted through the aperture of the lug I9. After being so installed, the resilience of the collar 2| causes same to assume its normal shape and thus retains the u foot 8 in place on the machine frame.

At the rear portion of the typewriter main frame I8, there is provided a pair of inwardly extending lugs 23 to receive a pair of feet 9, each lug 23 having a threaded hole 24 into which a 45 shoulder screw 25 is engaged, the shank 26 of the screw passing through an aperture 2l inthe body portion I2 of the rear foot, with the head of the screw disposed within the recess I3 thereof. Each lug 23 of the frame I8 has an edge 50 formed to provide downwardly extending ears 29 which partly overlie and engage a side wall of each foot 9 and thus secure the foot against rotation on the screw 25. The body portion I2 of each rear foot 9 has adjacent its rear edge 55 4an upstanding ridge 30 extending above the top In position lon thebase member I of the car-` rying case, the typewriter 1 has its rear feet 9' each resting upon a plate 3| shown more clearly in Figure 6, the plate 3| having at a side edge an upstanding flange 32, and at a rear edge an upstanding tongue 33 terminating in a forwardly projecting hook 34,'the free end of which is inclined upwardly. The front feet 8 of the typewriter rest on a plate 36 suitably secured as by rivets to the base member I0 of the carrying case, the plate 36 having centrally secured thereto an upstanding stud 31 slidably positioned in an aperture 38 formed in the body portion I2 of each front foot. The lower portion of each stud 8 is enlarged as shown at 38 to provide a broad base for the stud engaging the plate 36, the enlarged stud portion being disposed within the recess I3 of the front foot.

When placing the typewriter into the carrying case, same is held in rearwardly inclined position so that the rear feet 9 partly rest on the forward portions of the plates 3|, and the typewriter is urged rearwardly, itbeing noted that the rear feet 9 are guided in the rearward direction by sliding along the respective anges 32. The typewriter is pushed rearward in its inclined posi-v tion until the apertures 38 of the front feetl 8 are in registry with the studs 31, whence the front of the typewriter is lowered to its normal position. VDuring this rearward movement of the typewriter, the rear feet 9 slide under the hooks 34, the ridge 30 of each foot engaging the under surface of each hook 34. It vmay be here noted that this engagement of the ridge 30 against the hook prevents any actual metal-to- Vmetal contact between the typewriter 1 and base I0, in that the ridge 30 extends amply above the top surface of the lug 23 to assure that hook 34 be out of contact with the lug.

Portable typewriters are occasionally used without actual removal from the carrying case, the base I0 of the carrying case being placed on a desk or table and the cover II*v being raised therefrom. In such use, the improvements herelin set forth substantially prevent the transmission of operating noises from the typewriter to the base member I0 of the carrying case,'by absorbing sound vibrations of the typewriter at its points of support. The body portion I2 of each typewriter foot 4serves to dampen any sound vibrations of greater intensity carried to the feet, and the layer of sponge rubber I4 of each foot augments the sound dampening eilect of the body portion by preventing the transmission of any vibrations to the base, which may have been carried through the body portion I2, this eiect being had because of the greater resilience of the sponge rubber layers I4 than that of the body portion I2. It is also to be noted that the resilient contact of the ridge 30 on hook 34 further sound vibrations of lesser intensity. A further and salient advantage of my improved typewriter .feet is had because of the greater frictional contact made bythe sponge rubber foot portions on the smooth surfaced supporting member, to thus prevent the typewriter from shifting out of place during operation as a result of the vibrations induced therein.

The improved vibration absorbing typewriter foot herein set forth, comprising the combination of a relatively rm, yet resilient body portion formed of vulcanized rubber, and a layer of highly resilient material, such as sponge rubber, has a further important advantage in providing a substantially iirm foundation for the typewriter during operation, in that the typewriter foot, although preventing transmission of sound vibrations, is practically non-yielding and thus obviates the annoyance resulting from any movement of the typewriter bodily during typing, as would be had by use of a foot constructed entirely of a highly resilient material.

What is claimed is:

1. In a sound dampening support for a typewriter on a base, the ytypewriter having a frame including a horizontally disposed foot-receiving member, av foot of vibration absorbing material attachable to the frame member and adapted to cooperate with typewriter holding means on the base presenting a hook extending over said fra-me member, said foot comprising a rubber body portion having an upstanding ridge alongside the frame member and reaching above the top surface thereof for resilient engagement with the typewriter holding hook.

2. In a sound dampening support for a typewriter on a base, the typewriter having a frame including laterally extending horizontal foot-re-v ceiving members, in combination, a generally rectangular foot of vibration absorbing material detachably secured to the frame member, said frame member having downwardly directed ears overlying said foot and preventing rotation thereof, said foot being adapted to cooperate with tyewriter holding means on the base presenting a hook extending forwardly over said frame member, said foot having an upstanding ridge along the back edge of said frame member and reaching above the topy surface thereof for resilient engagement with the typewriter holding hook.

WILLIAM A. DOBSON.

Images