Patent Publication Number: US-RE39604-E

Title: Seating arrangement

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to the seating art and more particularly to an improved adjustable seating arrangement particularly adapted for providing variable contour back and/or seat portion to accommodate various configurational deformities to the user. 
     2. Description of the Prior Art 
     Many persons, including both adults and children, are unfortunately afflicted with various disorders causing postural configuration abnormalities which vary from the normal configuration of persons not so afflicted. For example, many suffering from cerebral palsy or muscular dystrophy have their upper torso, and/or buttocks, and/or upper legs twisted or otherwise in configurations that can differ considerably from the generally planer array generally associated with those same portions of the anatomy of persons not so afflicted. The distortions from the planar array can vary throughout the length of each of the body portions so that, for example, a chair back or chair seat having a single variation from the planar extending throughout the extent thereof cannot provide the desired support throughout the extent of each body portion. 
     There have heretofore been provided various adjustable seating arrangements which attempt to provide seating arrangements for such unfortunately disabled people. For example, in U.S. Pat. No. 4,367,897 there is shown a seating arrangement having a matrix of hard plastic elements connected to rigid tubular elements within a frame. Tensioning means are provided in the matrix but the tensioning means are not connected to the frame. The tensioning means only apply tension through the ball elements to various of the tube elements. Such an arrangement is comparatively costly and cannot provide the desired seating comfort or convenient contour arrangement often desired. 
     In U.S. Pat. No. 3,088,773 there is shown a frame having spaced apart rigid elements to which the seating and back portions are attached. In this arrangement the transverse strips are elastic and the ties and flexible. Inner members between the frames are rigid metal. There is no provision for adjusting the tension and the ties are not directly connected to the transverse strips and contouring cannot be provided. 
     In U.S. Pat. No. 3,913,978 there is a rigid seat and back unit coupled to a frame. In some embodiments described therein there are buckles for attaching the frame to the seat back unit. However, there is no provision for providing the desired contour to match the various bodily contours for the disabled persons for whom such a seat is desired. 
     In U.S. Pat. No. 4,928,334 there is shown a fabric web which is elastic and utilized as a spring element in an upholstered article of furniture such as a seat or a bed and the elastic fabric web is joined to a rigid frame members. No adjustment of contours is shown. 
     U.S. Pat. No. 3,363,667 shows the structure for attaching a webbing to the frame of a tubular chair such as a lawn chair but does not provide any contour adjustment to either the seat or the back. 
     U.S. Pat. No. 3,188,662 shows a chair for convalescent persons and provides mechanical movement of the back relative to the seat. No adjustments for contour configuration are shown. 
     U.S. Pat. No. 4,077,669 shows a resilient seating arrangement but has no adjustments and no spaced apart frame members. U.S. Pat. No. 3,154,345 shows a chair construction apparently intended to be used near water on, for example, boats and ships, and preferably utilizes rectangular cross-section elements as the frame and has a series of interwoven web members connected to the frame. No contour adjustment is shown or suggested. 
     Other seating arrangements are shown, for example, in U.S. Pat. Nos. 4,544,614, 2,459,843 and 2,485,111. None of these patents shows or suggests the desired contour configuration adjustability. 
     Other prior art seating arrangements for such disabled persons generally consist of costly complex and cumbersome solid seat inserts with many mechanical adjustments or multiple pieces of foam applied to achieve the desired contour for each individual persons. Such units are difficult to transport and tend to lose their adjustment so that the contours do not remain constant for the person. An individual custom molded contour chair covered with a padded cover has also been utilized but such units are very costly and need significant lead time. Further, should the contours of the individual change, as they often do with many diseases, and/or as the size of a person increases such as when a child grows, the molded contour chair cannot accommodate the changes. 
     Accordingly, there has long been a need for a seating arrangement for handicapped persons wherein the seating arrangement can provide adjustable contours throughout the back portion and/or seat portion in one, two or three dimensions to accommodate a wide variety of configurational disabilities of a user and also allow for convenient changing of the contours as the need arises for any individual person. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide an improved seating arrangement for disabled persons requiring configurational variations in the seat and/or back of the seating arrangement. 
     It is another object of the present invention to provide an improved seating arrangement for disabled persons in which adjustments to the contours of the back and/or seat may be quickly and easily made in one, two, or three dimensions. 
     It is yet another object of the present invention to provide a seating arrangement for disabled persons in which variations in the contours of the back and/or seat may be quickly and easily accomplished. 
     It is yet another object of the present invention to provide such a variable contour seating arrangement that is of sturdy construction, comparatively inexpensive to fabricate and adaptable for utilization with a wide variety of contour configurational requirements. 
     SUMMARY OF THE INVENTION 
     According to the principles of the present invention in a preferred embodiment thereof there is provided a frame member having a back portion and a seat portion. The back portion has a pair of spaced apart rigid support elements and each support element has a pair of rigid brace members in spaced apart relationship. The seat portion is also provided with a pair of spaced apart rigid support elements and each rigid support element of the seat portion has a pair of spaced apart rigid brace members. The rigid support elements of the seat portion are coupled to the lower part of the rigid support elements of the back portion. There is also provided a plurality of rigid transverse members extending between the rigid support elements of the back portion and also the seat portion to maintain the desired spacing therebetween. 
     A plurality of flexible webbing members are adjustably mounted on the rigid support elements of the back portion in a spaced apart array extending from the upper part to the lower part thereof adjacent the coupling to the seat portion. Each of the first plurality of flexible webbing members comprises a first and second flexible webbing portion and each end of the first flexible webbing portion is adjustably connected to the first of the pair of rigid brace members in each rigid support element and the second flexible webbing portion has its ends adjustably connected to the second rigid brace member of each of the first and second rigid support elements. Thus, for each of the first plurality of flexible webbing members there are provided four adjustment means; one at each of the rigid brace elements. 
     A plurality of joining means extend from regions adjacent the upper portion to regions adjacent the lower portion of the back member and the joining means are coupled to each of the adjacent first and second flexible webbing portions intermediate the first and second rigid support elements. 
     The first plurality of flexible webbing members and flexible back joining means are preferably fabricated from fabric such as nylon and are nonelastic. 
     The seat portion may similarly be provided with a second plurality of flexible webbing members in a spaced apart relationship extending from the inner end thereof which is connected to the back portion to the outer end and each of the second plurality of webbing members comprises a first and a second flexible webbing portion and each of said first and said second flexible webbing portions of said second plurality of flexible webbing members is substantially similar to the first and second flexible webbing portions of said first plurality of webbing members and are also provided with adjustment means at each of the third and the fourth rigid brace members of the third and fourth rigid support elements of the seat portion. 
     In preferred embodiments of the present invention the adjustment means for both the back portion and the seat portion are double “D” rings although, it will be appreciated, conventional buckles, hook and loop fasteners or the like may be provided for the adjustment. The adjustment means allows varying the length of each of the first and second webbing portions of the first plurality and second plurality of webbing members. 
     A pair of seat joining means substantially similar to the back joining means couple together the adjacent first and second flexible webbing portions of each of the plurality of the flexible webbing members in the seat portion. 
     Each of the flexible webbing members of the first plurality and second plurality thereof may be individually adjusted in length by suitable adjustment of the adjustment means and because of the four point attachment can provide a variable contour of each of the flexible webbing members thus provided a capability for a three dimensional contour variation throughout the extent of the back portion and the seat portion to accommodate a wide variety of configurational variations. 
     In other embodiments of the present invention, flexible strap means which may be flexible nylon webbing are provided to allow insertion of resilient pads to further provide contour adjustment and comfort to the seating arrangement. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other embodiments of the invention may be more fully understood from the following detailed description taken together with the accompanying drawings wherein similar reference characters refer to similar elements throughout and in which: 
         FIG. 1  is a front view of a seating arrangement according to the principles of the present invention; 
         FIG. 2  is a side elevational view of a frame member useful in the practice of the present invention; 
         FIG. 3  is a view along the lines  3 — 3  of  FIG. 1 ; 
         FIGS. 4 and 5  illustrate some of the configurations, in schematic form, for the flexible webbing members in accordance with the principles of the present invention; 
         FIGS. 6 ,  7  and  8  illustrate another embodiment of the present invention; 
         FIG. 9  illustrates, in schematic form, a webbing arrangement useful in the practice of the embodiment shown in  FIGS. 6 ,  7  and  8 ; 
         FIG. 10  illustrates another embodiment of the present invention; 
         FIG. 11  illustrates another embodiment of the present invention; 
         FIG. 12  illustrates another embodiment of the present invention; 
         FIG. 13  illustrates another embodiment of the present invention; 
         FIG. 14  illustrates another embodiment of the present invention; 
         FIG. 15  illustrates another embodiment of the present invention; 
         FIG. 16  illustrates another embodiment of the present invention; and 
         FIGS. 17 and 18  illustrate another embodiment of the present invention. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the drawings there is illustrated in  FIGS. 1 ,  2  and  3  a preferred embodiment generally designated  10  of the seating arrangement according to the principles of the present invention. The seating arrangement  10  is provided with a frame member generally designated  12  having a back portion generally designated  14  and a seating portion generally designated  16 . The back portion  14  has a first and a second rigid support elements as indicated at  18  and  20  in spaced apart relationship as indicated by the letter “a” in FIG.  1 . Each of the first and second rigid support elements  18  and  20  has a first and a second rigid brace member  22  and  24  in spaced apart, substantially parallel relationship as indicated by the letter “b” on FIG.  2 . The first rigid brace member  22  and second rigid brace member  24  of each of the first and second rigid support elements  18  and  20  define a pair of spaced apart planes and, in preferred embodiments of the present invention, the plane defined by the first rigid support element  18  and second rigid support element  20  are substantially parallel and together define a seating back support. 
     The seat portion  16  of the frame member  12  generally comprises a third rigid support element  26  and a fourth rigid support element  28  and each of said third rigid support element  26  and fourth rigid support element  28  are in spaced apart relationship and preferably are spaced apart substantially the distance “a” indicated in FIG.  1 . Each of the third rigid support element  26  and fourth rigid support element  28  comprise a third rigid brace member  30  and fourth rigid brace member  42  in spaced apart relationship indicated by the letter c on FIG.  2 . The spacing c may be the same as the spacing b or it may be greater than the spacing b or less than the spacing b. The third rigid brace members  30  and fourth rigid brace members  32  of each of the third rigid support element  26  and fourth rigid support element  28  define a pair of planes and the planes defined thereby are substantially parallel. 
     The seat portion  16  is connected to the back portion  14  at a lower part generally designated  34  of the back portion. In preferred embodiments of the present invention the frame member  14  is generally comprised of tubular metal and the joining of the seat portion  16  to the back portion  14  as indicated at  40 ,  42  and  44  may be, for example, by welding. Alternatively, bonding by way of appropriate adhesive may also be utilized if desired. Similarly, other types of fastening such as nuts and bolts, threading engagement or the like may be provided in particular applications. 
     A plurality of rigid transverse members are utilized to maintain the frame  12  in the spaced relationship shown in  FIGS. 1 and 2 . Such rigid transverse members are indicated at  FIG. 1  at  46  and in  FIG. 2  at  48  and  50 . The transverse members  46 ,  48  and  50  may be coupled to the rigid support elements  18  and  20  for the back portion  14  and  26  and  28  for the seat portion  16 . The plurality of transverse members may be, for example, metallic tubing coupled to the frame  12  thereby maintaining the spacing as indicated by the letter “a.” 
     In order to provide the desired variable contour of the seating arrangement  10  there is provided a first plurality of flexible webbing members generally designated  52  extending between the first rigid support element  18  and second rigid support element  20  for providing the variable contour to the back portion  14  of the seating arrangement  10 , the first plurality of flexible webbing members  52  are in a spaced apart relationship from an upper part  53  of the back portion  14  to the lower part  34  of the back portion  14 . The spacing between each of the flexible webbing members  52  may be selected as desired for particular applications as may the width of each of the flexible webbing members  52 . 
       FIG. 3  is a view along the line  3 — 3  of FIG.  1  and illustrates the details of the first plurality of flexible webbing members  52  and in particular the first flexible webbing member  52 ′ shown on FIG.  1 . It will be appreciated, however, that many details of the interconnections of the flexible webbing member  52 ′ and the other of the first plurality of flexible webbing members  52  are omitted from  FIG. 1  for clarity. 
     As shown on  FIG. 3  the flexible webbing member  52 ′ has a first flexible webbing portion  54  and a second flexible webbing portion  56 .  FIG. 3  illustrates the connection of the flexible webbing member  52 ′ to the first rigid support element  18  and the adjustable interconnection to the first rigid brace  22  and second rigid brace  24  of the first rigid support element  18 . The curved top most portion  14 ′ shown of  FIG. 2  of the back portion  14  has been cut away in  FIG. 3  for clarity so that the tubular nature of the first and second rigid brace members  22  and  24 , respectively, may be seen. The adjustable connections shown on  FIG. 3  are provided at each of the interconnections of one of the first flexible webbing members  52  to the first and second rigid support elements  18  and  20 . The first flexible webbing portion  54  has a first end section generally designated  58  adjustably connected to the first brace member  22  of the first rigid support element  18 . The adjustable connection is provided by the double “D” ring as indicated at  60 . It will be appreciated, however, that other adjustable connections such as buckles, hook and loop fasteners or the like may be utilized to provide the desired adjustability of the present invention. The second end  62  of the first flexible webbing portion  54  is similarly connected through D rings to the first rigid brace  22  of the second rigid support member  20  by similar double “D” ring adjustability interconnections. 
     The second flexible webbing portion  56  has a first end  64  adjustably connected to the second rigid brace member  24  of the first rigid support element  18  by double “D” rings indicated at  60  ′ which may be identical to the double “D” rings  60  described above. The second end  66  of the second flexible webbing portion  56  is similarly adjustably connected to the second rigid brace member  24  of the second rigid support element  20  by the indicated double “D” ring adjustment means. 
     Back joining means generally designated  68  are provided for joining together the adjacent first and second flexible webbing portions of each of the flexible webbing members  52 . In the embodiment  10  illustrated in  FIGS. 1 ,  2  and  3  there are a pair of back joining members  70  and  72 . The back joining members  70  and  72  are coupled to the first and second flexible support portions  54  and  56 . 
     In preferred embodiments of the present invention the flexible webbing members  52  and back joining members  70  and  72  are fabric and preferably a nylon webbing. For fabric and/or the nylon webbing structure, the first webbing portion  54 , second webbing portion  56  and each of the back joining means  70  and  72  may be coupled together by sewing as indicated at  74 . Similarly, the first and second webbing portions  54  and  56  may be coupled together in other locations such as indicated at  76  by sewing or the like. For the first flexible webbing members  52  and the back joining means  68  fabricated from materials which cannot be sewn, other connecting arrangements may be utilized such as bonding, heat sealing, stapling or similar structural arrangements well known in the art. 
     The seating portion  16  is provided with a second plurality of flexible webbing members generally designated  80  as shown on FIG.  1 . The flexible webbing members  80  may be substantially similar to each of the first plurality of flexible webbing member  52  utilized in the back portion  14 . In  FIG. 1  the adjustment means for connecting the second plurality of flexible webbing members  80  to the third and fourth rigid support elements  26  and  28  are omitted for clarity. The second plurality of flexible webbing members are provided on the seat portion  16  in a spaced apart relationship between an outer portion  16 ′ and an inner portion  16 ″ of the seating portion  16  and the adjustment means for connecting the second plurality of flexible webbing members  80  to the seating portion  16  may be substantially the same as described above in connection with FIG.  3 . As such, they may comprise double “D” rings, hook and loop, buckles or other adjustment means. 
       FIGS. 4 and 5  illustrate, in schematic form, some of the various contour configurations of the flexible webbing members  52  and/or  80  which may be achieved by varying the lengths of the first and second webbing portions thereof through the use of the adjustment means such as the double “D” rings  60 . In  FIG. 4 ,  FIGS. 4A ,  4 B and  4 C show symmetrical adjustment arrangements between the first and second rigid support elements and  FIG. 4D  shows a non-symmetrical arrangement. In  FIG. 5  there is illustrated in  FIGS. 5A and 5B  configurations having one or more curved portions of the flexible webbing member  52  as illustrated at  52 a and  52 b such curved portions are achieved by leaving slack in the first and/or second webbing portions such that when a person occupies the seating arrangement  10  it is pulled taut and curved to fit the contour of the particular body portion pressed thereagainst. Thus, the adjustment means  60  and  60 ′ in both the back portion  14  and seat portion  16  allows the plurality of flexible webbing members to be positioned in various configurations to conform to the desired contour for each individual. Such adjustment may be easily made by the use of the double “D” ring or other adjustment means and therefore the seating arrangement  10  can not only accommodate a large variety of different handicapped configurations of various bodily parts but also can be utilized for a large variety of different persons. 
     It will be appreciated that seat joining means similar to the back joining means  68  may be provided to couple together the first and second webbing portions of the second plurality of flexible webbing members  80  in a manner similar to that shown for the back joining means  68 . 
     Referring now to  FIGS. 6 ,  7 ,  8  and  9  there is shown another embodiment, generally designated  100  of a seating arrangement  102  according to the principles of the present invention. The seating arrangement  102  is comprised of a frame member  104  having a back portion  106  and a seat portion  108 . The back portion  106  is generally similar to the back portion  14  of embodiment  10  described above and is comprised of a first rigid support element  110  and a second rigid support element  112  in, preferably, a parallel, spaced apart relationship. Each of the first rigid support element  110  and second rigid support element  112  has a first rigid brace member  114  and second rigid brace member  116  which, in preferred embodiments, are substantially parallel and coplanar and thus similar to the corresponding first and second rigid brace members described above in connection with embodiment  10 . 
     The seat portion  108  is generally similar to the seat portion  16  described above and is comprised of a third rigid support element  115  and fourth rigid support element  116 , which are generally similar to the third rigid support element  26  and fourth rigid support element  28  described above. The third rigid support element  115  has a first rigid brace member  188  and second rigid brace member  120  and the fourth rigid support element  116  has a first rigid brace  112  and a second rigid brace  124 . In preferred embodiments the third rigid support element  115  and fourth rigid support element  116  are in spaced apart parallel relationship. The first rigid brace member  118  and second rigid brace member  120  are in spaced apart relationship and preferably in parallel coplanar relationship. Similarly, the first rigid brace  122  and second rigid brace  124  are in spaced apart relationship and preferably in parallel, coplanar relationship. 
     Transverse members  126  and  128  are provided to maintain the first rigid support element  110  and second rigid support element  112  of the back portion  106  in said spaced apart relationship and for other purposes as described below. Transverse member  130  is also provided to maintain the third rigid support element  114  and fourth rigid support element  116  in spaced apart relationship. 
     The back portion  106  has an upper part  131  and a lower part  132 . The seat portion  108  is coupled to the back portion  106  in regions adjoining the lower part  132  and extends outwardly therefrom in the first direction indicated by arrow  134 . 
     In preferred embodiments of the present invention, the frame  102  is metallic and the interconnections of the various portions thereof is by welding. It will be appreciated, however, that other structures for coupling the various components together may be utilized such as threading, bonding, unitary molding or the like. 
     In the embodiment  100  there is provided a fifth rigid support element  136  comprising a fifth rigid brace  138  and sixth rigid brace  140 . The fifth rigid brace  138  and sixth rigid brace  140  are preferably parallel to each other and coplanar in a plane perpendicular to the planes defined by the first rigid support element  110  and the second rigid support element  112 . The fifth rigid support element  130  is spaced from the first rigid support element  110  and second rigid support element  112  in a second direction indicated by the arrow  140  opposite the first direction  134  and is coupled to the transverse members  126  and  128 . 
     A plurality of first flexible strap means  142  are provided in the back portion  106  of embodiment  100  and in a spaced array from regions adjacent the upper part  131  to regions adjacent the lower part  132  and extend between the first rigid support element  110  and second rigid support element  112 . 
     The structure for providing the plurality of first flexible strap means is shown, generally schematically, in  FIG. 9  for strap means  142 ′ and such structure may be utilized for some or all of the strap means  142 . 
     As shown in  FIG. 9 , there is provided a first plurality of flexible webbing connecting members generally designated  150  comprised of a plurality of pairs of first tab means  152  each having a first end  154  and second end  156 . Each of the first tab means  152  are coupled as indicated at  158  to the adjacent first brace member  114  of each of first rigid support element  110  and second rigid support element  112 . Rivets, bolts and nuts, bonding or other known fastening means may be utilized to connect the first tab means  152  to the rigid braces. As shown on  FIG. 9 , each of the first tab means  152  is connected at  158  to the first brace member intermediate the first end  154  and second end  156  of each of the tab means  152 . The flexible webbing connecting members  150  also comprises a plurality of pairs of second tab means  160 . Each of the second tab means  60  has a first end  162  and a second end  164 . Each of the second tab means  160  are connected at their second end  164  to the rigid brace member  114  as indicated at  158 . 
     As shown in  FIG. 9  the first end  154  of tab  152  and first end  162  of tab  160  extend from the coupling  158  towards the first brace member  116 . The first tab means  152  and second tab means  160  may be fabricated from nylon webbing or any other desired material suitable for the purpose. 
     Each of the first flexible strap means  142  has a first end  170  adjustably connected by a pair of “D” rings  172  to one of the first end  154  of a pair of the first tab means  152  and a second end  174  adjustably connected to the first end  154  of the other of the pair of first tab means  152  by double “D” rings  172 . The first flexible strap means  142  which may also be fabricated of nylon webbing or other suitable material, extends around each of the second rigid brace members  116  in the first direction  134  therefrom. 
     A second plurality of flexible strap means  180  are also provided. In preferred embodiments of the present invention there is one flexible strap means  180  for each flexible strap means  142 . The flexible strap means  180  is shown on  FIG. 9  in a “slack” condition in order to illustrate the principles of the present invention. The flexible strap means  180  overlies the adjacent flexible strap means  142  and each have a first end  182  adjustably connected to the first end  162  of one of the pair of second tab means  160  by double “D” rings  172 , and a second end  184  adjustably connected to the first end  162  of the other of said pair second tab means  160  by double “D” rings  172 . 
     If desired, resilient pads  184  may be placed between first flexible strap means  142  and second flexible strap means  180  in regions indicated at  186  and  188  to provide additional contouring and comfort. In the central portion  190  on  FIG. 9  the flexible strap  180  is shown closely adjacent the flexible strap  142 . However, the adjustable connecting provided by the double “D” rings allows enough “slack” so that flexible strap  180  may be spaced from flexible strap  142  in the central portion  190  as indicated by the dotted line  180 ′. In such a condition, a resilient pad may be placed in the space  192 . 
     Control means, generally designated  200 , are also provided in embodiment  100  for increasing the number of contour configurations which may be achieved by the present invention. As shown on  FIG. 9 , the control means  200  comprises a third flexible strap means  202  which may be fabricated of nylon webbing or other suitable material having a first end  204  adjustably connected by the double “D” rings  172  to the second end  156  of one of the pairs of first tab means  152  and a second end  204  adjustably connected by double “D” rings  172  to the second end  156  of the other of the pair of tab means  152 . The third flexible strap means  202  extends between the first rigid brace members  114  of the first rigid support element  110  and second rigid support element  112 . The third flexible strap means  202  is preferably provided aligned with and adjacent to each of the first and second flexible strap means  142  and  180 , respectively, and is positioned in the direction  140  therefrom. 
     The control means  200  further comprises slide fastener means  206  comprised of slide fastener elements  208  and  210  slidably mounted on first flexible strap means  142 , second flexible strap means  180  and third flexible strap means  202 . 
     The control means  200  also further comprises a fourth plurality of adjustably length flexible strap means  212  comprised, in the embodiment  100 , of a pair of adjustable length flexible strap members  214  and  216 . The adjustment in the lengths of the flexible strap members  214  and  216  is provided by the double “D” rings  172  connecting the ends thereof together. Each of the flexible strap member  216  and  214  extend around one of the fifth and sixth rigid brace members  136  and  140 , respectively, and to the slide fasteners  210  and  208 , respectively. Adjustment of the lengths of the fifth and sixth flexible strap members moves the slide fasteners  208  and  210  in the directions indicated by the arrows  134  and  140  to provide additional contouring capability and sliding the slide fasteners  210  and  208  in the direction indicated by the arrow  220  on  FIG. 9  further increasing the number of three dimensional configurations available in the practice of the present invention. 
     In the embodiment of the seating arrangement  10  described above the frame  12  is illustrated by including the back portion  14  with the two spaced apart rigid support elements  18  and  20 . Similarly the seat position  16  is illustrated by including the spaced apart rigid support elements  26  and  28 . It has been found, however, that in some applications, rather than providing the two spaced apart rigid support elements  14  and  20 , each having rigid brace members  22  and  24  in spaced apart relationship, it may be advantageous to have the back portion comprised of two rigid, spaced apart plate-like members. 
       FIG. 10  illustrates an embodiment  248  having a frame generally designated  250  which may be utilized in the practice of the various embodiments of the present invention. The frame  250  has two rigid spaced apart support elements  252  and  254  which may be considered rigid side members of frame  250  and each of which has a back portion  256  and a seat portion  258 . The rigid support element or side members  252  and  254  may be fabricated of wood, metal, plastic or other materials suitable for the purpose and have a thickness, indicated by the letter “t” sufficient to provide the desired strength and rigidity for the anticipated uses. The side members  252  and  254  may be substantially identical to each other and are provided with walls  260  defining spaced apart rows of a plurality of apertures  262  and  264  in the back portion  256  and the seat portion  258 . 
     A plurality of flexible webbing members  266  which may be substantially similar to the flexible webbing members  52  described above and provided with appropriate double “D” rings (omitted for clarity) for length and contour adjustment. The flexible webbing members  266  may be inserted through corresponding apertures  260  in each of the side members  252  and  254  in the manner described above for flexible webbing members  52 . 
     A plurality of rigid, transverse brace members  268  which may be fabricated from any suitable material such as wood, plastic, metal or the like, interconnect the two side members  252  and  254  to maintain the desired spacing “a” therebetween. The side members  252  and  254  provide the same function and purpose as the two rigid spaced apart support elements  18  and  20  of the embodiment  10 . 
     The flexible webbing members  266  may extend in the back portion  256  from regions near the top  256 ′ to regions near the bottom  256 ″. Similarly, the flexible webbing members  266  may extend from regions adjacent the front  258 ′ of the seat portion  258  to regions adjacent the rear  258 ″ thereof. The flexible webbing members  266  may be adjusted to provide the desired contours and configurations for various applications. 
     In some applications of the present invention it may be desirable to provide the structure with the capability of being folded so that the seat structure may be conveniently stored and/or carried when not in use. It has been found that such foldable capability may be achieved, for example, by providing lockable hinges in the rigid transverse members. 
       FIGS. 11 and 12  illustrate a foldable embodiment generally designated  280  of the present invention. The flexible webbing has been omitted for clarity in illustrating the structure of the frame  282  of embodiment  80 . In  FIG. 11 , which is a partially exploded view, the frame  282  is generally similar to frame  12  of the embodiment  10  described above. The frame  282  has the two rigid support elements  283  and  285 , which are generally similar to rigid support elements  18  and  20 , in the back portion  287  thereof in spaced apart relationship indicated by the letter “a”. The frame  282  is also provided with a seat portion  291  and has rigid support elements  293  and  295  which are generally similar to the rigid support elements  26  and  28  of the embodiment  10  described above. To provide the folding, the rigid transverse members illustrated at  284  and  286  are provided with toggle lock hinges  288 . The toggle lock hinges  288  may be of conventional design providing a rigid brace in the position illustrated in  FIGS. 11 and 12  but allowing pivoting of the rigid transverse brace portions  284 ′ and  284 ″ as well as  286 ′ and  286 ″ in the directions indicated by the arrows  289  and  290  as there is pivotal motion about the pivots indicated at  292  and  294  (FIG.  12 ). 
     The pivotal motion about the pivots  292  and  294  in the directions indicated by the arrows  289  and  290  provide the close juxtapositions of rigid support elements  283  to rigid support element  285  of the back portion  287  and close juxtaposition of rigid support element  293  to rigid support element  295  of seat portion  291 . 
     In the foldable embodiments of the present invention, each of the rigid transverse members are provided with the toggle lock hinges  288 . The positioning of the transverse members is selected so that there is no interference therebetween during the folding. 
     The folding capability of the present invention may also be achieved in the embodiment  248  described above in connection with FIG.  10 . In such an embodiment  268  the rigid transverse members thereof are provided with toggle lock hinges such as toggle lock hinges  288  of  FIG. 11  so that the rigid support elements or side members  252  and  254  may be moved into close juxtaposition. 
     Similarly, folding capability may be provided in the other embodiments of the invention as desired for particular applications. 
     The principles of the present invention may be achieved by various configurations of webbing extending between the rigid side members in a back portion and a seat portion of a chair to provide the three-dimensional contour variations. The various frame members of the embodiments described may be utilized in combination with various webbing configurations. 
       FIG. 13  illustrates, partially in schematic form, an embodiment, generally designated  300 , of the present invention. In embodiment  300  there is a frame generally designated  301 . The frame member  302  is generally similar to frame member  12  of embodiment  10  described above. In  FIG. 13 , only one half of the structure is shown. The other half of the structure may be identical to the structure shown. The frame  302  has a first rigid support element  304  has a first rigid brace member  306  and second rigid brace member  308  which are similar to first and second rigid brace members  22  and  24  described above. 
     A plurality of flexible webbing members, generally designated  310  are provided on frame member  302  in a spaced array as described above for the webbing members  52  in embodiment  10 . 
     Each flexible webbing member  310  has a first flexible webbing portion  312  having a first end  314  attached to a pair of “D” rings  317 . Each flexible webbing member  310  also is provided with a second flexible webbing portion  316  having a first end  318  connected to “D” rings  320 . The first flexible webbing portion  312  extends from the first end  314  thereof around second rigid brace member  308  and through a slide fastener  322  which may be similar to slide fasteners  208  and  210  described above, and is movable in the directions indicated by the arrow  324 . The second flexible webbing portion  316  extends from the first end  318  thereof through the slide fastener  322 . 
     A flexible tension strap  326  is connected to first rigid brace member  306  by, for example, screw  328 . Rivets, bolts and nuts of any other desired fasteners may be substituted for the screw  328  to secure tension strap  326  to the first rigid brace member  306 . The tension strap  326  has a first end  328  connected to the “D” rings  316  and a second end  330  connected to the “D” rings at  320 . 
     In embodiment  300 , there is also provided joining means  332  which may be similar to the joining means  68  described above as shown in embodiment  10 . The joining means  332  limits the movement of slide fastener  322  in the direction indicated by  324 a. 
     By movement of the slide fastener  322  and, if desired, lengthening or shortening either or both first flexible webbing portion  312  and second flexible webbing portion  316  at “D” rings  317  and  320 , respectively, the contour of the webbing member  310  may be changed to provide various configurations thereof. 
       FIG. 14  illustrates another embodiment, generally designated  350  of a webbing arrangement useful in the practice of the present invention. In embodiment  350  a frame  352 , which may be similar to the frame member  104  of embodiment  100 , but the fifth and sixth rigid brace members may be omitted, if desired. That is, the transverse member  354  is not coplanar with first rigid brace member  356  of first rigid support element  358  and first rigid brace member  360  of second rigid support element  362 . The frame  352  also is provided with second rigid brace members  364  and  366  of first rigid support element  358  and second rigid support element  362 , respectively. 
     A plurality of flexible webbing members  368  are provided on the frame  352  in spaced apart relationship as described above. The flexible webbing members  308  are comprised of a first flexible webbing portion  370  having a first end  372  connected to “D” rings  374 . The first flexible webbing portion  370  extends from the “D” rings  374 , around second rigid brace member  364 , around second rigid brace member  366  to second end  376  to “D” rings  378 . 
     A second flexible webbing portion  380  is provided and extends from a first end  382  thereof through “D” rings  384 , around first rigid brace member  356  and  360  to second end  386  connected to “D” rings  388 . 
     A flexible tension strap means  390 , which may be similar to tension strap  326  described above in embodiment  310 , is provided and has tension strap member  392  on one side and tension strap member  394  at the other side of the frame  352 . Tension strap member  392  connects the first end  372  of first flexible webbing portion  370  of “D” rings  374  and the first end  382  of second webbing portion  380  at “D” rings  384 . Similarly, tension strap member  394  connects the second end  376  of first webbing portion  370  at “D” rings  378  and second end  386  of second flexible webbing portion  380  at “D” rings  388 . 
     The tension strap means  396  may be connected, for example, by sewing, though other connecting means such as rivets, bolts or the like may be used at the places indicated generally at  396 . 
     If desired, joining means  398 , which may be similar to joining means  68  described above, may be provided for connecting the plurality of flexible webbing members  368 . 
     The remote ends of the tension strap members  392  and  394  may be connected, for example, by sewing, adjacent the connections to the various “D” rings, as indicated at  400 . 
     By adjusting the lengths of first and second flexible webbing portions  370  and  380  at the “D” ring connections, variations in the contour may be achieved. 
     The configurations of the various flexible webbing members illustrated in the various embodiments of the present invention may be utilized in various combinations on the seat portion and the back portion of each embodiment. Similarly, if desired, various flexible webbing members may be incorporated, if desired, in any back portion or seat portion to allow particular configurations to be achieved for specific application. For example, the flexible webbing member  348  of embodiment  350  may be interspersed with flexible strap means  142  of embodiment  100  in any desired variety of combinations to achieve a particular contour configuration. 
     The various frame structures illustrated in the various embodiments of the present invention may be utilized with various webbing configurations to provide a seating arrangement as desired for particular applications. 
       FIG. 15  illustrates another embodiment generally designated  410  which combines various webbing configurations of the embodiments described above to achieve the variable configurations desired. As shown on  FIG. 15  there is a frame generally designated  412  and a plurality of flexible webbing members  414  which may be the same as the frame  352  and flexible webbing members  368  described above in connection with embodiment  350  shown on FIG.  14 . In embodiment  410  there is also provided tension strap means  416  which may be similar to tension strap means  390  described above. 
     In embodiment  410 , there is provided a plurality of flexible strap means  418  which is similar to the plurality of flexible strap means  180  shown in embodiment  200  on FIG.  9 . As shown on  FIG. 15 , the flexible strap means  418  is shown in a slack condition and has a first end coupled to auxiliary tension strap means  420  at “D” rings  422  and  424 . The provision of flexible strap means  418  allows incorporation of pads, generally indicated at  426 ,  428  and  430  to provide additional contour configurations. Slide fasteners  422  and  434  may also be provided for further contour variations as desired. The flexible strap means  418  and flexible webbing members  414  extend through the slide fasteners  432  and  434 . Each of the flexible strap means  418 , flexible webbing members  424 , tension straps  420  and auxiliary tension strap means  420  are connected together as indicated at  436 . Similarly, tension strap means  420  have there remote ends connected at the “D” rings  438 ,  440 ,  442  and  444  which provides the connections to the flexible webbing members  414  as indicated at  446 . Similarly, the remote ends of auxiliary tension strap means  420  are connected together as indicated at  450 . The connections at  436 ,  446  and  450  may be by sewing, rivets, bolts or the like. The position of the connections shown at  436  relative to the frame  412  provides the limited to lateral movement of slide fasteners  432  and  434  in the directions indicated by the arrow  452 . 
       FIG. 16  illustrates another embodiment, generally designated  500  according to the principles of the present invention which incorporates various structural elements of the various embodiments described above. 
     Embodiment  500  is provided with a frame  502  which may be similar to the frame member  104  described above in connection with embodiment  100  descried above in connection with  FIGS. 6 ,  7 ,  8  and  9  and also incorporates control means  504  which may be generally similar to control means  200  in embodiment  100  and comprises slide fasteners  506  and  508  and adjustable length strap means  510  and  512  connected to double “D” rings  514  and  516  and to the slide fasteners  506  and  508 , respectively. The adjustable length strap means  510  and  512  engage a rigid support element  518  comprising rigid brace  520  and  522 , respectively. 
     The embodiment  500  is provided with a plurality of flexible webbing members  524  which may be similar to the flexible webbing member  368  of embodiment  350  described above and tension strap means  526  which may be similar to tension strap means  390  of embodiment  350 . 
     Adjustment of the length of the various portions of flexible webbing member  524  and the strap means  510  and  512  as well as the position of slide fasteners  506  and  508  provides the variations in contour according to the principles of the present invention. 
     A further modification of the embodiment  500  may be provided by the addition of flexible strap means  530  which may be the same as flexible strap means  418  of embodiment  410  described above to allow positioning, for example, pads  532  in a manner similar to the pads  426 ,  428  and  430  described above. Auxiliary tension strap means  534  may also be provided and is the same as auxiliary strap means  420  of embodiment  410  and is connected to flexible strap means  530  by “D” rings (not shown). 
     Each of the embodiments of the present invention may include various coverings over all or part, as desired, of the back portions and seat portions. Such covering, indicated generally at  600  on  FIG. 2  may be cloth, padded cloth, plastic, or any other material suitable for the purpose. 
     The toggle lock hinge  288  shown in embodiment  280  on  FIGS. 11 and 12  provide one arrangement for allowing structure according to the principles of the invention to be arranged into a compact configuration. Such toggle lock hinges provide lateral compactness of the structure. In other applications of the present invention it may be desirable to provide vertical compactness of the back portion and horizontal compactness of the seat portion. Such compactness may be provided by the use of well-known telescoping tubes in the rigid support elements of the back portion and seat portion. Such telescoping tubes may, if desired, also be used in the transverse members in place of or in addition to the toggle locking hinges  288  to provide lateral compactness. 
     The use of the telescoping tubes in the rigid support elements of the back portion and seat portion of the present invention is readily adapted in those embodiments wherein there is no fixed connection of any portion of the webbing or straps to the frame. Such connection is shown, for example, in the embodiment  300  at the screw  328 . 
       FIGS. 17 and 18  illustrate one embodiment, generally designated  650 , of the present invention, incorporating telescoping tubes. As shown on  FIGS. 17 and 18 , a frame  652  in provided which may be substantially the same as frame  352  of embodiment  350  shown on FIG.  14 . However, the rigid brace members  654 ,  656 ,  658  and  660  are telescoping tubes utilizing well-known telescoping tube structures. Such telescoping tube structures as utilized in rigid brace members  654 ,  656 ,  568  and  660  comprise an outer housing tube  664  and an inner telescoping tube  666 . The inner tube  666  is slidably mounted in the housing tube  664  for reciprocal sliding movement therein into and out of the plane of the paper. Well-known spring loaded detent structures (not shown) may be utilized to retain the relative position of the inner tube  666  at various locations in housing tube  664 . 
     Adjustable contours of the back portion and/or seat portion of the frame  652  may be provided in embodiment  650  by the use of a plurality of flexible webbing members  668  and  670 . Flexible webbing member  668  has a first end  672  around rigid brace member  656  and connected to “D” rings  674 . The second end  676  of flexible webbing member  668  is around rigid brace member  660  and is connected to “D” rings  678 . 
     Similarly, flexible webbing member  670  has a first end  680  around rigid brace member  654  and connected to “D” rings  682 . Flexible webbing member  670  has a second end  684  around rigid brace member  658  and connected to “D” rings  686 . 
     A flexible strap means  688  which may be similar to flexible strap means  180  of embodiment  200  shown on  FIG. 9  may be utilized to allow positioning of resilient pad means  690 ,  691  and  694 . 
     Proper length adjustment and tensioning of the flexible webbing members  668  and  670  and flexible strap means  688  are illustrated in the enlarged view shown on FIG.  18 . As shown thereon, a control means generally designated  700  is provided for tensioning the flexible webbing members  668  and  670  as well as flexible strap  688 . 
     The control means  700  has an anchor strap  702  encircling rigid brace members  654  and  656  and is, in preferred embodiments of the present invention, detachably secured together by, for example, hook and loop type connection as indicated at  704  for the loop and  706  for the hook. Buckles or other similar connecting means may be used as desired in place of the hook and loop fasteners. 
     A tension strap  710  has a first end  712  connected to “D” rings  682  for tensioning at the first end  680  of flexible webbing  670 . The tension strap  710  has a second end  714  connected to “D” rings  674  for tensioning at the first end  672  of flexible webbing  668 . The tension strap  710  is connected, for example, by sewing, as indicated at  716 , to anchor strap  702 . 
     The first end  712  and second end  714  of tension strap  710  are connected into a loop at the “D” ring connections, for example, by sewing, as indicated at  718  and  720 . 
     A secondary tension strap  722  may be provided to apply tension to a first end  724  of flexible strap  688  in these embodiments utilizing the flexible strap  688 . The secondary tension strap  722  as shown on  FIGS. 17 and 18 , is connected to “D” rings  726 . The second end  724  of flexible strap  688  is also connected to “D” rings  726 . The secondary tension strap  722  may be an extension of the first end  712  of tension strap  710  as shown on  FIGS. 17 and 18  or, if desired, may be a separate strap connected to anchor strap  702 . 
     The detachable connection of the anchor strap  702  as shown by the hook  706  and loop  704  fastening permits the anchor strap  701  to be loosened when telescoping action of the rigid brace members  654 ,  656 ,  658  and  660  is desired. After such telescoping action, the anchor strap may be reconnected to the desired tension to provide the predetermined tensioning of the flexible webbing  668  and  670  and flexible strap  668 . 
     Slide fastener means  728  and  730  may be provided for additional contour adjustment. The flexible webbing  668  and  670  and flexible strap  688  are connected to the slide fasteners  728  and  730  as described above for the slide fasteners  208  and  210  of embodiment  100  shown on FIG.  9 . 
     This concludes the description of the preferred embodiments of the present invention. Those skilled in the art may find many variations and adaptations of the present invention and the following claims are intended to cover all such variations and adaptations falling within the true scope and spirit thereof.