Chair

Abstract

A chair includes a base, a backrest and a back brace supporting the backrest from the base. The base may include a seat assembly made up of a pan and a flexible support membrane over an upward opening cavity defined by the pan. The back brace may provide a flexible support for the generally planar member formed as a serpentine shape defined by a first curved portion opening toward said base and a second curved portion opening away from said base. The backrest may have an outer frame made from an extruded member having a generally tubular member and a fin coextruded with said generally tubular member to provide a fastening substrate for panels. The base may further include a leg assembly made up of a plurality of leg members and a joiner member joining horizontal portions of the leg members.

1 . A chair, comprising:
 a base, a backrest and a back brace supporting said backrest from said base;   said base comprising a leg assembly and a seat assembly supported by said leg assembly;   said seat assembly comprising a pan and a flexible support membrane, said pan having a bottom member and at least one sidewall extending upwardly from said bottom defining an upwardly opening cavity, said flexible support membrane supported by said at least one sidewall over said cavity in a manner sufficient to support a person substantially with said support membrane.   
     
     
         2 . The chair as claimed in  claim 1  wherein said at least one sidewall surrounds substantially the sides and back of said pan and further including a flexible filler member between said support membrane and said bottom. 
     
     
         3 . The chair as claimed in  claim 1  further including at least one pad member supported by said support membrane. 
     
     
         4 . The chair as claimed in  claim 1  wherein said pan is molded as a unitary member. 
     
     
         5 . The chair as claimed in  claim 4  including stiffening ribs formed in said bottom member extending to said sidewall. 
     
     
         6 . The chair as claimed in  claim 4  wherein said bottom member defines a generally planar lower surface and at least one channel in said lower surface, said at least one channel configured to receive a horizontal portion of said leg assembly wherein said generally planar lower surface defines a stacking surface for engaging another chair. 
     
     
         7 . The chair as defined in  claim 6  wherein said leg assembly comprises a plurality of leg members, each of said leg members having a generally vertical portion and a generally horizontal portion, said horizontal portions of said legs defining said horizontal portion of said leg assembly. 
     
     
         8 . The chair as claimed in  claim 7  wherein said horizontal portion of said leg assembly further includes a joiner member, said joiner member joining said horizontal portions of said leg members. 
     
     
         9 . The chair as claimed in  claim 8  wherein end portions of said horizontal portions of said leg members are welded to said joiner member. 
     
     
         10 . A chair, comprising:
 a base, a backrest and a back brace supporting said backrest from said base;   said base comprising a leg assembly and a seat assembly supported by said leg assembly;   said back brace defining a flexible support for said backrest, wherein said backrest is capable of limited motion with respect to said base by flexing of said back brace, wherein said back brace is defined by a generally planar member having one end portion that is configured to attach to said base, an opposite end portion that is configured to attach to said backrest and an intermediate portion, said intermediate portion formed as a serpentine shape defined by a first curved portion opening toward said base and a second curved portion opening away from said base.   
     
     
         11 . The chair as claimed in  claim 10  wherein said second curved portion above said first curved portion is further away from said base than said first curved portion. 
     
     
         12 . The chair as claimed in  claim 10  wherein said first curved portion and said second curved portion have approximately the same radius of curvature. 
     
     
         13 . The chair as claimed in  claim 12  wherein said radius of curvature is approximately 1.5 inches. 
     
     
         14 . The chair as claimed in  claim 10  wherein said generally planar member is tapered from said opposite end portion toward said one end portion. 
     
     
         15 . A chair, comprising:
 a base, a backrest and a back brace supporting said backrest from said base;   said base comprising a leg assembly and a seat assembly supported by said leg assembly;   said backrest comprising an outer frame and at least one panel supported within said frame, said outer frame made from an extruded member having a generally tubular member and a fin coextruded with said generally tubular member, said fin extending inwardly from said tubular member, wherein said at least one panel is fastened to said fin.   
     
     
         16 . The chair as claimed in  claim 15  wherein said fin has a scalloped shape. 
     
     
         17 . A chair, comprising:
 a base, a backrest and a back brace supporting said backrest from said seat;   said base comprising a leg assembly and a seat assembly supported by said leg assembly, wherein said leg assembly comprises a plurality of leg members, each of said leg members having a generally vertical portion and a generally horizontal portion, wherein said leg assembly further includes a joiner member, said joiner member joining said horizontal portions of said leg members.   
     
     
         18 . The chair as claimed in  claim 17  wherein end portions of said horizontal portions of said leg members are welded to said joiner member. 
     
     
         19 . The chair as claimed in  claim 17  wherein said generally vertical portion has a complex shape. 
     
     
         20 . The chair as claimed in  claim 19  wherein said complex shape comprises a swage configuration. 
     
     
         21 . The chair as claimed in  claim 20  wherein said swage configuration comprises a rectilinear cross section that transforms to a curved cross section. 
     
     
         22 . The chair as claimed in  claim 19  wherein said complex shape comprises multiple bends. 
     
     
         23 . The chair as claimed in  claim 22  wherein said multiple bends face in generally opposite directions. 
     
     
         24 . A chair, comprising:
 a base, a backrest and a back brace supporting said backrest from said base;   said base comprising a leg assembly and a seat assembly supported by said leg assembly;   said seat assembly comprising a pan and a flexible support membrane, said pan having a bottom member and at least one sidewall extending upwardly from said bottom defining an upwardly opening cavity, said flexible support membrane supported by said at least one sidewall over said cavity in a manner sufficient to support a person substantially with said support membrane;   said back brace defining a flexible support for said backrest, wherein said backrest is capable of limited motion with respect to said base by flexing of said back brace, wherein said back brace is defined by a generally planar member having one end portion that is configured to attach to said base, an opposite end portion that is configured to attach to said backrest and an intermediate portion, said intermediate portion formed as a serpentine shape defined by a first curved portion opening toward said base and a second curved portion opening away from said base;   said backrest comprising an outer frame and at least one panel supported within said frame, said outer frame made from an extruded member having a generally tubular member and a fin coextruded with said generally tubular member, said fin extending inwardly from said tubular member, wherein said at least one panel is fastened to said fin; and   said base comprising a leg assembly and a seat assembly supported by said leg assembly, wherein said leg assembly comprises a plurality of leg members, each of said leg members having a generally vertical portion and a generally horizontal portion, wherein said horizontal portion of said leg assembly further includes a joiner member, said joiner member joining said horizontal portions of said leg members.