Patent Publication Number: US-8113581-B2

Title: Supportive back overlay for wheelchair back

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of application Ser. No. 12/669,686, filed Jan. 19, 2010, which is a U.S. national stage application under 35 U.S.C. §371 of PCT/US/2008/067500, filed Jun. 19, 2008, which claims priority to provisional application Ser. No. 60/961,912, filed Jul. 25, 2007, all of which are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     The invention relates generally to seating and more specifically an attachment to the original equipment back of a chair, for example a wheelchair, to enhance support characteristics of the back, and more specifically to a supportive back overlay that can be attached to the original sling or soft back of a wheel chair or other chair to provide added support. 
     Wheelchairs generally are constructed from a metal frame having the overall configuration of a chair. The frame includes wheels on the bottom so that the wheelchair can be moved about to increase mobility of the seated user. The wheelchair frame supports a seat extending between two sides of the frame and usually includes arm rests on each side of the seat for comfort and stability. The frame includes vertically extending back support posts with a back support structure extending between the posts to support the seated user&#39;s back. In many styles of wheelchairs, the seat and the back support or both are constructed from a flexible material, such as canvas cloth, vinyl or the like. Since these materials are flexible, they generally bow or assume a concave configuration when the user is seated and resting against the back support. These types of back supports are sometimes referred to as sling backs. 
     Many users find these flexible back supports to be uncomfortable and desire firmer support and less bowing behind their backs. Replacement back supports constructed from substantially rigid materials are known, but usually require removal of the original back support, modification of the frame and mounting of the replacement back support to the frame with hardware using tools. Hence, the replacement back is not simple to attach and once the replacement back is attached, it is cumbersome and time consuming to remove. This can be particularly problematic for an injured or disabled individual who requires the use of a wheelchair and may have no help in modifying his or her wheelchair. It would be advantageous, therefore, to have a substantially firm back support that can be easily and conveniently attached to or removed from the back of a wheelchair, or any other chair, without the use of hardware or tools. 
     SUMMARY OF THE INVENTION 
     A supportive back overlay that can be used on the back of a chair, for example a wheelchair, which can be attached to the original back by a suspension element. One aspect of the supportive back overlay comprises a supportive cushion with a suspension element that slips over the original equipment chair back to hold the cushion in position behind a seated user&#39;s back. The suspension element can be associated with the supportive cushion in any acceptable manner. Representative or illustrative aspects of association include, but are not limited to, securing the in the cushion cover, by molding it into the cushion itself, or by attaching it to anchors that are affixed to the cushion. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a rear perspective view of a supportive back overlay; 
         FIG. 2  a perspective view of one embodiment of a supportive back overlay suspension element; 
         FIG. 3  is an exploded rear perspective view of the suspension element; 
         FIG. 4  a rear plan view of a supportive back overlay; 
         FIG. 5  is rear a perspective view of a wheelchair employing the supportive back overlay; 
         FIG. 6  is an exploded front perspective view of a wheelchair and supportive back overlay; 
         FIG. 7  is a rear perspective view of another aspect of a supportive back overlay; 
         FIG. 8  is another rear perspective view of an aspect of a supportive back overlay of  FIG. 7 ; 
         FIG. 9  is another rear perspective exploded view of an aspect of a supportive back overlay with a portion of the clip molded into the foam cushion shown in phantom; 
         FIG. 10  is a top plan view of the supportive back overlay of  FIG. 9 ; 
         FIG. 11  is front perspective view of another aspect of a support back overlay suspension element partially enclosed in a cover, with a cover shown in phantom; and 
         FIG. 12  is front perspective view of another aspect of a support back overlay suspension element partially enclosed in a cover, with the cover shown in phantom. 
     
    
    
     DETAILED DESCRIPTION 
     One aspect of a supportive back overlay is indicated generally by reference number  10  in the figures. In general, the supportive back overlay  10  includes a suspension element  12 , which also may be referred to as a clip, and a support element  14 . The support element includes a cushion  16  and a cover  18 . Suspension element  12 , also referred to as a clip, comprises a frame  20  having opposed, spaced apart mirror image sections  22  and  24 , respectively, which are connected at the top by bails  26  and  28 . The bails  26 ,  28  are designed to extend over or hang on the upper edge of a back of a chair, for example, over sling back B of wheelchair W as seen in  FIG. 5 . It will be appreciated that supportive back  10  can be easily placed or hung on the sling back and does not require any mounting hardware or tools to install. 
     Wheelchair W, as illustrated, is conventional in design having a rigid frame F. Of particular interest is that wheelchair W includes a conventional original equipment sling back B and a seat S. In general the wheelchair sling back B is constructed from a substantially flexible material, such as a canvas, fabric or even vinyl and is attached between two upright back elements U of the wheelchair frame. In any event, the sling back B generally is not rigid and can bow, and hence offers less support and comfort when a user is positioned on seat S and leans back against sling back B. Although supportive back  10  is illustrated in use on a wheelchair, it will be understood that the scope of the present invention is intended to cover any use of the supportive back on any type of seating structure that employs its own original equipment back. The bails are placed over sling back B and the support element  14  is held suspended against the front side of the sling back B, where it can support the back of a user seated in the wheelchair. The suspension element  12  can be formed from a heavy gauge wire, such as stainless steel wire. The illustrated configuration has a lobed design, which is aesthetically pleasing. The ornamental design is not critical, however, and in one aspect of the invention, suspension element  12  has sufficient width to extend across a substantial area of the sling back B. This adds to the stability and support characteristics of supportive back  10 . 
     The back section  24  of the suspension element is visible on the back surface of the sling back B and includes an optional inlay  30  made of Plexiglas in the illustrated embodiment. Inlay  30 , as shown, primarily is decorative and can bear indicia  32 , such as the company name or logo. There can be any form of ornamentation of structures in the area occupied by inlay  30 , without departing from the scope of the invention. As seen in  FIG. 6 , inlay  30  has attachment holes  31  is secured to bosses  31  which are integral with the frame by fasteners  32  through holes  33  in the bosses. The front section  22  of frame  20  is secured in the cover  18 , as will be described below. It will be appreciated that, although suspension element  12 , as illustrated, comprises a wire frame, any type of suspension element that allows easy attachment of the supportive back over the sling back B is acceptable and intended to be within the scope of the invention and claims. It could simply be a U-shaped element with substantially flat solid sections or any other design that accomplishes the intended purpose. 
     Cushion  16 , as shown, can be a constructed of foam such as a medium density foam. However, soft or high density foam also may be used as long as the foam can be properly formed or molded. Alternatively, cushion  16  can be an air cell cushion, similar to those disclosed in U.S. Pat. No. 4,541,136, which is incorporated herein by reference. Cushion  16  provides a comfortable, yet supportive surface on which the user can rest his or her back. The cushion  16  generally has some flexibility or “give” when pressure is applied, but does not yield or bow as much as the original seat back and provides good support and stability and prevents the seated user from sinking or tilting back too far. 
     Cover  18  can be constructed from a durable, washable fabric, such as nylon or the like. Cover  18  has a back wall  34  with an external surface  36  that contacts the front surface of the sling back and hence preferably is constructed from a material having a higher coefficient of friction or tackiness, such as a rubberized fabric, that keeps the supportive back from sliding or moving when attached to the sling back. As seen in  FIG. 7 , cover  18  has a top opening  38  covered by a closable flap  40  that opens into a main inside compartment  42  that is sized and configured to snugly hold cushion  16 . Flap  40  can be closed by hook and loop fastener or other appropriate means. Inside compartment includes pocket  44  defined by back wall  34  and an inner wall  45  for the insertion of front section  22  of suspension element  12 . In the illustrated embodiment, there is a pair of opposed snaps  46  between the back wall  32  and wall  45 . When front section  22  of the suspension element is positioned in the pocket, the snaps  46  are engaged so that the back wall and pocket are fastened together with the front section  22  of the suspension element secured in-between, keeping front section  22  from sliding around in the pocket. 
     When assembled, cushion  16  and the front section  22  of the suspension element  12  are secured inside cover  18 . Bails  26  and  28  and rear section  24  of the suspension element are exposed. Bails  26  and  28  are dimensioned so that there is a space  48  between rear section  24  of the suspension element and back wall  34  if the cover. The user can slide the suspension element over the upper edge of the sling back and suspend or hang the supportive back  10  on the original back. The front and rear sections  22  and  24  of suspension element  12  provide support and stability. The suspension element  12  and cushion  16  are sufficiently wide to extend substantially across the sling back to provide a firmer, more comfortable seat back by supplementing the original equipment sling back B. Cushion  16  flattens and firms up the sling back. The supportive back overlay  10  can be provided in an array of sizes. It can be attached to just about any chair back and is easily removed. It requires no modification of the wheelchair frame, any specialized equipment, clamps or tools to attach or remove. 
     In the illustrated embodiment, suspension element  12  is shown removably secured in pocket  44  of the cover. This facilitates disassembly of the supportive back so the cover may be washed or the cushion replaced and so forth. However, the suspension element, whatever configuration used, can be more permanently attached to the cover, or may be removably attached by some other arrangement. The support element  14  could include hook-like means on the upper edge, either short or longer, for example designed like staffs with the vertical body of the staff extending the vertical length of the support element to provide addition stability and so forth. 
     Another representative embodiment of a supportive back overlay, indicated by reference number  50  in the drawings, is shown in  FIGS. 7 and 8 . Supportive back overlay  50  includes a contoured, molded foam cushion  52  and a suspension element  54 . Suspension element  54  includes a first or outer section or side  56  and a second, spaced apart section or side  58 . As shown, second side  58  is molded into foam cushion  52 . Pairs of bails  60  and  62  extend up and out of the cushion. First side  56  is spaced apart from the back of cushion  52  so that the pairs of bails  60  and  62  can be placed over the upper edge of a chair sling back, allowing the cushion to be suspended in front of the sling back to support the back of a seated user. The configuration of the two sides ( 56 ,  58 ) of suspension element  52  can be of any desired configuration. The two sides do not necessarily have to be mirror images. However, second side  58  that is molded inside cushion  52  should be of a substantial area and configuration so as to me molded securely within the cushion. As show, the configuration of the first side  56  is lobed, similar to suspension element  12 . Second side  58  is substantially rectangular, having spaced apart vertical members  64  and  66  comprised of spaced apart vertical members  64 A,  64 B and  66 A and  66 B. Each pair of vertical members can be connected by cross braces  70 . It will be appreciated that the curved sections of these vertical members that protrude out of the foam cushion form the pairs of bails  60 ,  62 . In any event, vertical members  64 A and  66 A can be connected by horizontal members  72  to add rigidity. As stated above, any configuration of the suspension element is intended to be within the scope of the invention. 
       FIGS. 9 and 10  illustrate and other representative embodiment of the supportive back overlay of the present invention, indicated generally by reference number  80 . Supportive back overlay  80  includes a cushion  82  and a suspension element  84 . Suspension element  82  is configured similarly to suspension element  54  described above. However, supportive back overlay  80  includes four spaced apart anchors  86  molded into cushion  82 . Anchors  86  protrude from adjacent the four corners of the flat back wall  88  of cushion  82 . As shown, anchors  86  have a substantially circular body  90  with a concentric, spindle-like protrusion  92 . Protrusion  92  defines a central, threaded bore  94 . Circular body  90  has a pattern of perforations or holes  96 . Circular body  90  is molded within the cushion during the molding process and the holes  96  fill with foam material during the molding process to better secure the anchors in the cushion. 
     Suspension element  84  includes four cross braces  70 , of the type described above in reference to suspension element  54 . Cross braces  70  define centrally placed holes  72 A. Screws  98  extend through holes  72 A of the four cross braces and threadedly engage threaded bore  94  to secure suspension element  84  to the back of cushion  82 . Supportive back overly  80  is suspended on a sling back B in manner similar to that described above. 
       FIGS. 11 and 12  illustrate alternative ways to attach a suspension element  100  in an inner pocket  102  of a cover  104 . Cover  104  includes a back wall  106 . In  FIG. 11 , there are a pair of spaced apart, opposed tabs  108  secured to the inside face of back wall  106 . Tabs  108  include a snap  110 . A second side  112  of suspension element  100  is positioned within pocket  102 . The tabs  108  are secured around a narrow area of side  112  and snapped, thereby securing second side  112  inside the cover. A cushion then can be inserted in pocket  102 . The snaps  108  can be unsnapped to remove the suspension element from the cover. Similarly, in  FIG. 12  a single, longer securing strip  114  can be placed across a narrow area of the second side  112  of a suspension element and secured to the back wall  106  with a series of snap  116  to releasably hold the second side of the suspension element within pocket  102  of cover  104 . 
     It will be appreciated that the foregoing written description and accompanying drawings are illustrative only, demonstrating the best mode of working the invention presently known to the inventor, and should not be used to construe the scope of the invention or claims in a limiting sense.