Arm Rest

The present invention relates to an arm rest which is removably securable to a desk top.

More and more medical problems are being encountered by people who work at desk top computers, typewriters, etc. These medical problems include bursitis as well as neck and upper back strain. Surprisingly enough, the reason for the problems is the positioning of ones wrist and elbow on a hard desk top surface which is the typical arm positioning required to operate a mouse for a computer or even the keyboard for the computer. However, at the same time it is not practical to build a desk top with a fully cushioned surface or to in some other way, permanently alter the desk top to more comfortably position ones wrist and/or elbow.

The present invention provides an arm rest which removably attaches to a desk top. The arm rest is used to comfortably support the forearm of a person using the arm rest and alleviates the strain on ones wrist and elbow which would otherwise be positioned on the desk top.

The arm rest of the present invention comprises a rigid support frame, a cushion member atop the frame and a cantilever attached from beneath and extending to a position forwardly of the frame. The frame has a forward overhand region spaced above the cantilever member to define a desk top fitting gap between the frame and the cantilever. Through the use of the cantilever, the arm rest does not require anything in the way of permanent attachments to affix it to the desk top but rather is simply slipped over the desk top without the use of tools whatsoever.

As a result of the removable or releasable fitting of the arm rest to the desk top, it is not dedicated to a particular location and as such can be moved from desk to desk as desired.

The above as well as other advantages and features of the present invention will be described in greater detail according to the preferred embodiments of the present invention in which;

FIG. 1 is a perspective view of a desk top arm rest according to a preferred embodiment of the present invention;

FIG. 2 is an exploded perspective view of the arm rest of FIG. 1;

FIG. 3 is a side view of the arm rest of FIG. 2 when fitted to a desk top;

FIG. 4 shows the arm rest of FIG. 3 used for operating a computer mouse;

FIG. 5 shows the arm rest of FIG. 3 used for operating a computer keyboard;

FIG. 6 shows pair of arm rests modified slightly from the arm rest of FIG. 1 in accordance with a further preferred embodiment of the present invention.

FIG. 1 shows a portable arm rest generally indicated at 1. This arm rest is removably fittable with substantially any desk top where the desk top has some type of an overhang. See for example, FIGS. 3, 4 and 5.

The arm rest itself has a cantilever generally indicated at 3 which comprises a pair of curved bars 5, interconnected at their rearward ends through an L shaped bracket 7 and at their forward ends within a rubber desk grip 9. Note that the desk grip 9 has a hollowed center 11 resulting in a peripheral gripping edge 12 on the grip member 9.

As can be seen in the drawings, the cantilever bars or rods 5 diverge rearwardly from one another along the length of the cantilever. This enhances the balance of the cantilever where it connects to the rest of the arm rest. On the other hand, the converging of the cantilever bars at the forward end of the cantilever maximizes or concentrates its gripping ability beneath the desk top as will be described later in detail.

The cantilever bracket 7 secures to a rigid frame generally indicated at 29. This frame is formed by a U-shaped outer frame portion 31 with a pair of cross-bars 33 and 35 secured by welding or the like across the U-shaped frame. Flat metallic plate 23 sits down within the outer frame portion 31 directly atop cross-bars 33 and 35 and is secured again by welding or the like to the rigid support frame 29.

An upper cushioned support generally indicated at 13 includes a lower rigid base 19 which in the preferred embodiment is made of plywood. A high density foam layer 18 seats directly atop the rigid base 19 and an outer cover 15 is provided over the foam. In the preferred embodiment, the foam is about 1/2" in thickness and cover 15 is preferably made from an upholstery fabric or the like.

Again, in the preferred embodiment a pair of T-nuts 21 are fitted directly into the base 19 of pad 13. The pad is secured to plate 23 by means of threaded screws as shown which fit up through a pair of openings 25 in the plate and thread into the T-nuts in the base of the pad.

For storage and shipping purposes, the cantilever 3 with its mounting bracket 7 is formed separately of the frame 29. The forward cross-bar of the frame is fitted with downwardly extending bolts 37 secured as for example, by welding, against rotation in the cross-bar. Bracket 7 of the cantilever has a pair of bolt receiving openings in its horizontal leg to allow the bracket to be fitted to the cross-bar by the bolts 37 and a pair of threaded nuts are provided to secure the cantilever bracket on the cross-bar bolts.

When the cantilever is secured to the frame as shown for example in FIG. 1, a gap 8 is defined between the cantilever and the forward region of the frame which overhangs the cantilever.

In order to fit the arm rest to a desk top, the cantilever is positioned beneath the desk top, the forward part of the frame is located over the desk top and the arm rest is then simply pushed onto the desk top where it fits in the gap 8 between the cantilever and the forward overhang region of the frame. Note that the outer frame portion 31 is covered at its front end with a soft preferably rubber or rubber-like wrapper 39. This wrapper has a two fold function. Firstly, it protects the desk top against marring and scratching by eliminating direct contact of the rigid material of the frame with the desk top. Secondly, the high co-efficient of friction in the wrapper provides a very effective grip which resists sliding on the desk top and provides a very positive location for the arm rest.

The cap 9 on the forward end of the cantilever also has a soft preferably rubber or rubber-like construction. It, like the wrapper 39, again provides a very positive grip to the underside of the desk top The grip of the cap is further enhanced through the provision of depression 11 where the peripheral edge 12 of the cap produces a very highly concentrated and positive contact with the underside of the desk top.

As best seen in FIG. 3 of the drawings, the vertical leg of the L-shaped bracket 7 provides a very effective stop and determines maximum forward positioning of the arm rest on the desk top DT. The frame wrapper 39 and cap 9 resist any rearward movement of the arm rest particularly when it is weighted down by the arm of a user as shown in FIGS. 4 and 5 of the drawings. It is to be noted in FIG. 3 that even when cantilever bracket 7 is pushed fully up against the front edge of the desk top, a substantial amount of the arm rest hangs in open space outwardly beyond the desk top.

FIG. 4 shows a computer operator with his or her forearm seated on the arm rest for hand manipulation of a mouse M of a computer screen S. The forearm muscle of the computer operator sits directly atop the elevated cushioned surface 13 of the arm rest and raises the operators arm slightly above desk top level so there is little, if any weight taken by the hand and wrist of the operator. This also substantially frees up the operator's hand and positions it properly for easy movement of the mouse.

The same forearm support is provided by the arm rest when working the keyboard of FIG. 5, where once again, the hand is somewhat elevated from the desk top for a very effective positioning of the hand relative to the keyboard panel.

From a manufacturing standpoint, the arm rest is made from inexpensive easy to assemble components. For example, the cantilever bars 5 like the outer frame portion 31 are preferably made from 1/4" bar stock. The remaining construction is also made from relatively inexpensive off the shelf components.

Although the cantilever arms are made from a rigid material, the cantilever itself because of its configuration is resiliently bendable or deflectable along its length. This adapts the arm rest to fit to different desk top thicknesses because once a load is placed on the arm rest, the cantilever deflects to grip the desk top from beneath as earlier described. Furthermore, the resilient nature of the cantilever allows some up and down movement at the free end of the arm rest which hangs outwardly away from the desk top. This produces a comfortable shock absorber effect over the length of the arm rest.

As best seen in FIG. 3 of the drawings, for comfort purposes, the upper pad portion 13 of the arm rest includes a rounded forward end 27 which hangs outwardly beyond the rigid frame portion 31 of the arm rest. This ensures that the operators arm as shown in FIG. 4 of the drawings does not come into contact with any rigid surfaces on the arm rest. Furthermore, the rounding of the edge 27 reduces interference with the operators arm as it moves on the arm rest.

In all of the embodiments described above, the cushion is fitted extending along the length of the arm rest. This set up is used for a desk top which is strictly transverse to the body positioning of the operator. FIG. 6 of the drawings on the other hand shows an arm rest generally indicated at la having a cantilever 3a, a rigid frame 29a and an upper pad 13a. In this particular case, the upper pad 13a rather than running along the length of the frame is turned at right angles to the frame. This design is applicable for desk tops having work surfaces at right angles to one another and where the arm rest can be secured to one of the work surfaces with the mouse or computer terminal on the other work surface.

In terms of attachment and use of arm rest 1a, it is identical to arm rest 1 as earlier described.

As will be appreciated from the description above, a particularly advantageous feature of the arm rest of the present invention is that it can quickly and easily be moved from one desk top another and does not require either any permanent attachments nor any tools to locate the arm rest in its working position.

Although various preferred embodiments of the present invention have been described herein in detail, it will be appreciated by those skilled in the art, that variations may be made thereto without departing from the spirit of the invention or the scope of the appended claims.