Abstract:
A sheet material sling is supported on a horseshoe-shaped device mounted on three casters which forms a vehicle to support a knee of a user. Two such supports are used, unconnected to each other by users who must kneel in their work and must scoot along a support surface. Provisions are made for the supports to be interconnected by a flexible connector or by a rigid table like sheet.

Description:
BACKGROUND OF THE INVENTION 
     Many jobs require a worker to be on his or her hands and knees and after a short time of this type of work, the knees begin to be painful. In the past such workers have equipped themselves with pillows or with knee pads which strap onto the leg or are held in place by elastic bands. These devices ease the pain or postpone the time for pain to begin, but, in general, do not provide long term relief. 
     It is an object of the present invention to provide a sheet material sling or hammock for each knee and to mount the sling or hammock on a wheeled frame so as to provide mobility in the kneeling position. It is another object of this invention to provide such a device with pockets or pouches to hold tools or other small items, such as nails, rivets, etc. that might be used by the worker. Still another object of this invention is to provide a means for joining two knee supports in a fixed or semifixed spacing. Other objects will become apparent from the more detailed description which follows. 
     BRIEF SUMMARY OF THE INVENTION 
     This invention relates to a pair of mobile knee supports comprising two identical wheeled vehicles, each designed to receive and support a human knee; each said support including an outer U-shaped strip and an inner U-shaped strip spaced concentrically apart, three spaced casters located respectively, at the center of said strips and at both ends of said strips; a rigid support for each said caster depending downwardly from at least one of said strips; and a flexible knee support sheet material suspended from said inner strip and adapted to receive said knee and to suspend the knee above the lowest level of said casters. 
     In a specific and preferred embodiment of the invention each caster is supported by, and attached to, a horizontal leg of a short section of an L-beam while the vertical leg of the beam section is rigidly fastened to the inner strip. In another embodiment a pocket or pouch is suspended between adjacent portions of the inner and outer strips for the purpose of holding small tools or other items needed by the worker. In still other embodiments two of the knee supports are temporarily attached to a single plate or board which permits the individual supports to be moved about as a pair which are spaced apart the desired distance for normal use. Similarly, a pair of knee supports of this invention may be tied together with one or more ropes tied to eyebolts on the knee supports. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The novel features believed to be characteristic of this invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and method of operation, together with further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawings in which: 
     FIG. 1 is a top plan view of a knee support of this invention; 
     FIG. 2 is a rear elevational view of a knee support of this invention; 
     FIG. 3 is a side elevational view of a knee support of this invention; 
     FIG. 4 is a top plan view of a plate for attaching two knee supports of this invention; 
     FIG. 5 is a rear elevational view of the plate of FIG. 4; 
     FIG. 6 is a perspective view of two knee supports tied together with a rope; and 
     FIG. 7 is a cross-sectional view taken at 7--7 of FIG. 1. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The invention and its structure are best understood by reference to the accompanying drawings. 
     In FIGS. 1-3 and 7 there are shown the features of the knee support of this invention. The general theme of this invention is to provide a pair of wheeled vehicles for supporting a workers knees when he or she is kneeling. Each knee is supported above the floor on which the device rolls. This makes kneeling much easier on the worker, who need not rise and kneel when moving about, and, furthermore, each knee is supported in a sling which conforms to the contours of each knee and, thus, prevents the formation of any painful locations that occur when a knee is pressed against a hard surface. 
     The main supporting framework of the device comprises two spaced U-shaped, or horseshoe-shaped, strips; namely, inner strip 11 and outer strip 12, which are generally rectangular in cross-section and are positioned with the long axis of the rectangle in the vertical direction so as to provide as much resistance as possible to sagging or bending in the vertical direction. Inner strip 11 carries most of the stresses resulting from supporting approximately half of a worker&#39;s weight, and, accordingly, is larger than outer strip 12. For a normal size worker, inner strip 11 may be about 1/4×11/2 inches in cross-section while outer strip 12 may be about 1/8×3/4 inch in cross-section. These two strips 11 and 12 are spaced apart about 1-2 inches, preferably 11/2 inches, and held in that spacing by tubular spacers 18 and bolts 17 at the front portion 13 of the device. These dimensions are, of course, only illustrative, and other sizes and shapes may be useful in other embodiments. At the rear portion 14 of the device, the spacing is maintained by bending outer strip 12 twice to form a return bend 19 that is bolted to inner strip 11 by one of bolts 23. 
     At each spacer location 18 and 19 there is a short section of L-beam 21 or 22 having a vertical leg 37 which is attached by bolts 23 to inner strip 11 so as to have horizontal legs 38 of all L-beams 21 and 22 lie in a common horizontal plane. Each horizontal leg 38 forms a supporting surface to which is bolted the mounting plate of a caster 15 or 16 by means of bolts 39. Each caster 15 and 16 includes a yoke 25 which is mounted on a ball bearing plate so as to permit 360° rotation of caster yoke 25 and thus permit casters 15 and 16 to roll in any direction. L-beam sections 21 and 22 are positioned so as to have horizontal legs 38 spaced below strips 11 and 12. For normal sizes, the top surface of strips 11 and 12 is about 4-5 inches above floor level, on the surface upon which casters 15 and 16 are supported. 
     The knee supporting means is a flexible sheet material 28 fastened to inner strip 11 by means of clamping strips 26 at the front 13 and 27 at the sides adjacent the rear portion 14 preferably adjacent L-beam sections 22. Clamping strips 26 and 27 are fastened to inner strip 11 by bolts 29. Preferably edges of sheet material 28 are clamped between clamping strips 26 or 27 and inner strip 11. Usually three spaced locations for clamping sheet material 28 to inner strip 11 are sufficient to provide secure attachment. Sheet material 28 may be leather, fabric, plastic sheet, or the like. Proper spacing and sizing of sheet material 28 will permit its lowest elevation, when supporting a knee, to be a minimum distance, e.g., at least 1/8 inch above floor level. 
     An additional optional feature of this invention is the provision of one or more pouches or open-top pockets 30 which are placed in the available spaces between inner and outer strips 11 and 12. Pouches 30 may be made of leather, fabric, plastic sheeting, or the like, and preferably are made with a stop lug 40 that will support the pouch 30 and prevent it from falling downwardly without need for bolting the pouch 30 to strips 11 and/or 12. Flanges 20 may also be employed. Generally, pouches 30 are used to carry any small items frequently needed by the worker, e.g., tools, nails, screws, power drill, drill bits, etc. The knee support of this invention can also be built with permanent pouches 30 that are not easily removable from the knee support frame. 
     In some use applications, it is desirable to connect two knee support devices to each other for ease of handling. In FIGS. 4 and 5 there is shown a plate or sheet 31 which serves to join two knee support devices into a non-adjustable configuration. Plate 31 has two horseshoe shaped openings 32 which closely, if not exactly, conform to the central opening of the knee support device, generally defined by inner strip 11. Openings 32 admit the knees of the worker to the sheet material sling 28 for each knee. Plate 31 is frictionally engaged with two knee support devices by way of tabs 33 which depend downwardly from the lower surface of plate 31 and frictionally contact inner and outer strips 11 and 12 generally in the same spaces where 30 would be positioned. In this embodiment any tool holders, nail cups, or the like will be attached to any available area on the top surface of plate 31. 
     In FIG. 6 there is shown another way to keep two knee support devices from becoming separated. Here, one or two eye bolts 35 are attached to each knee support device at any convenient location, e.g., at one or two of L-beams 21 and 22. Suitable ropes, chains, wires 36 can be attached to respective eye bolts 35 so as to keep two knee support devices together. Any other suitable connecting means can be used for this purpose. 
     FIG. 7 shows how pouch 30 may be disposed between inner and outer strips 11 and 12. Each pouch 30 may have a stop means 40 which keeps pouch 30 from falling downward from strips 11 and 12 when loaded with tools or other items carried in the pouch 30. Flanges 20 may be employed in place of, or in addition to, stop means 40. If desired, pouch 30 may be bolted to or cemented to the strips 11 and 12. 
     While the invention has been described with respect to certain specific embodiments, it will be appreciated that many modifications and changes may be made by those skilled in the art without departing from the spirit of the invention. It is intended, therefore, by the appended claims to cover all such modifications and changes as fall within the true spirit and scope of the invention.