US2155999A - Typewriting machine - Google Patents

Description

Apri125, 1939. RGTHOMPSON 2,155,999

TYPEWRITING MACHINE Filed Sept. 4, 1936 (Eil ATTORN EY Patented Apr. 25, 1939 UNITED STATES PATENT OFFICE TYPEWRITING MACHINE Application September 4, 1936, Serial No. 99,378

3 Claims.

This invention relates to typewriting machines, and especially to devices for supporting and securing such machines in a manner to reduce the noise resulting from their operation.

Much of the noise incident to the use of typewriting machines results from the magnification of the sounds of the operating mechanism by reason of the transmission of such so-unds, in themselves small, through the machine-frame to the desk or working surface on which the machine rests, said surface actingv as a sounding board, with a resulting magnifying effect.

Rubber or other resilient mountings, comprising cushions of various kinds and intended to insulate against such transmission, are well known. The common characteristic of these prior devices, however, is that the resilient material is under compression, resulting in an obviously inefficient structure, because the immediate increase in density increases the sound and vibration transmission qualities of the material. In addition, the constant pounding to which a typewriter is subjected during use has the cumulative effect of so distorting and compacting the resilient material as to render it absolutely valueless as an insulator in a comparatively short time.

These disadvantages are overcome in this invention, in which the resilient material is placed under tension, thus lessening its density and increasing the insulating value, and continued use, up to a reasonable limit, acts actually to improve the insulating qualities.

In viewof the foregoing, a general object of the invention is to provide an improved mount or foot for typewriters and like machines, of simple and inexpensive construction and elfective to substantially prevent the transmission of operating noises from the machine to the desk platform or other structure upon which the machine rests.

Other objects and advantages will hereinafter appear.

In the drawing, Figure 1 is a fragmentary side elevational view of a typewriter mounted on a desk platform, the mount or foot being shown in central section, and

Figure 2 is a perspective view of the typewriter foot.

A typewriter 3 has its frame 4 formed to receive a set of four feet 5, the frame 4 having a series of holes, each threaded to receive a screw 6 for attachment of the typewriter feet thereto. In use the typewriter is usually positioned on the desk platform or table 'I which may be a part of the usual secretarial desk wherein the typewriter carrying platform is swingably mounted to the desk in the well known manner so that by tilting the platform, the typewriter is concealed within the desk when not in use. Y

The screw 6 may have a cylindrical head 8 hav- `5 ing a slot therein to receive a screw driver bit for attaching the foot 5 to the typewriter. The screw head 8 fits snugly but removably in a cylindrical collar 9 having at its upper end an inturned rim I6 overlying the shoulder of the screw and adapt- 10 ed to be clamped between the screw head 8 and the typewriter frame 4. The cylindrical collar 9 constitutes the body portion of an inner member of the typewriter foot and has at its lower end an l outwardly projecting bottom flange II disposed l5 substantially normal to the axis of the screw 6. The typewriter foot also includes an outer member having a cylindrical wall I 2 at the top of which is an inwardly projecting flange I 3l overl lying the ange Il of the inner member, the 2b ange I3 having a central aperture through which the body portion 9 projects so that the typewriter is spaced from the top flange of the outer member. The cylindrical wall I 2 of the outer member extends substantially below the bottom 25 of flange II and is adapted to rest directly upon the platform 1, the wall I2 having an outwardly directed flange I4 providing a broad area for contact with the platform. A

It is to be noted that the respective flanges II, 30 I3 match and are in parallelism with each other, as are also the cylindrical wall I2 and the body portion 9. A resilient rubber ring I6 is interposed between the inner and outer foot members, being secured as by vulcanizing to the confronting faces 35 of the said members. That is, the rubber ring I6 is vulcanized to both the iianges I I and I3, and to the outer surface of the collar 9 and the inner surface of the cylindrical wall I2 of the outer member. o

At the outer margin of the bottom of rubber ring I6 is an integral bead or annular portionl 2| disposed between the periphery of the bottom flange II and the wall I2 to keep these members from actual metal-to-metal contact. A similar 45 bead 22 is provided at the top of the ring IB, being disposed within the inner edge of the top ange II and the body portion 9.

Under load of the typewriter, the inner member is pressed downwardly and tends to further 50 separate the flanges II and I3 thus causing a stretching or tensioning of the rubber ring I6. The arrangement of the flanges II, I3 with their confronting faces substantially matching each other, and being secured to the rubber ring I6 55 entirely over these matching faces, assures that the entire ring I6 be subjected to the tensioning stress imparted by the load of the typewriter. The ring I6, being under tension, vhas a greater vibration absorbing effect than were same put under a shearing or compression stress. The inner member of the typewriter foot is thus suspended, by the rubber ring I6, on the outer member and may move downwardly under the load of the typewriter or to absorb any vibrations occurring therein, to prevent transmission of these vibrations to the platform 1. The rubber beads- 2|, 22, although permitting any necessary downward movement of the inner member, prevent same from moving excessively in a lateral direction, thereby providing a relatively flrm but yieldable support for the typewriter.

The outer ange I4 of each typewriter foot may, in coaction with other devices secured to the platform 'I, serve to maintain the position of theltypewriter on the platform. As shown herein, `ametal plate I'I may be of ample size as to underlie substantially the entire area of the typewriter and is secured to the platform 1 by screws I8. A felt mat I9 is interposed between the plate I'I and the platform 'I and is effective in dampening sound vibrations emanating from the typewriter. The plate I'I has peripheral portions 2U overlapping a part of the flange I4 of the typewriter foot and coacts therewith to hold the typewriter in place on the platform during operation or, when the typewriter is tilted into the desk.

Variations may be resorted to within the scope of the invention, and portions of the improvements may be used without others.

Having thus described my invention, I claim:

1. A resilient foot for support of a typewriter on a platform., comprising in combination, an inner member having a cylindrical body portion adapted for attachment to the typewriter and a flange projecting outwardly from the bottom thereof substantially at right angle to the axis of said body portion, an outer member having a cylindrical wall embracing said inner member and having an inwardly projecting top ange overlying and matching the flange of said inner member in parallelism therewith, and a resilient ring interposed between said inner member and said outer member and vulcanized to the confronting faces of said inner and outer members,

- the body portion of said inner member reaching above said top flange and the cylindrical wall of said outer member reaching below the flange of said inner member and being restable on a platform, to permit said resilient ring to tension freely under load of the typewriter.

2. A resilient foot for support of a typewriter on a platform, comprising in combination, an inner member having a hollow cylindrical body portion adapted to removably receive a shouldered screw therein for attachment of the foot to a typewriter, said body portion having an inturned rim for clamping between the screw shoulder and the typewriter, said inner member having a flange projecting outwardly from the bottom thereof, an outer member having a, cylindrical wall embracing said inner member and having an inwardly projecting top flange overlying and matching the bottom flange of said inner member in parallelism therewith, and a resilient rubber Aring interposed between said inner and outer members vulcanized to substantially the entire confronting faces of said inner and outer members, the body portion of said inner member reaching above said top flange and the cylindrical wall of said outer member reaching below the flange of said inner member and being restable on a platform, to permit said resilient ring to tension freely under load of the typewriter.

3. A resilient foot for support of a typewriter on a platform, comprising in combination, an inner member having a cylindrical body portion adapted for attachment to a typewriter and a flange projecting outwardly from the bottom thereof substantially at right angle to the axis of said body portion, an outer member having a cylindrical wall embracing said inner member and having an inwardly projecting top flange overlying and matching the bottom flange of said inner member in parallelism therewith, and a resilient rubber ring vulcanized to the confronting faces of said inner and outer members, said resilient ring having an upper annular portion between the body of said inner member and the edge' of the top ange and having a bottom annular portion between the edge of the flange of said inner member and the wall of said outer member, the body portion of said inner member reaching above said top flange and the cylindrical wall of said outerI member reaching below the ilange of said inner member and being restable on a platform, to permit said resilient ring to tenl sion freely under load of the typewriter.

RUSSELL G. THOMPSON.

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