Abstract: An office chair is provided having a back assembly which is configured to provide supplemental support to the back of a chair occupant in addition to the support provided by the primary support surface of the chair back. The chair back includes a lumbar support unit having a lumbar support pad that includes a plurality of support rings disposed one inside of the other.

Abstract: An office chair is provided having a back assembly which is configured to provide supplemental support to the back of a chair occupant in addition to the support provided by the primary support surface of the chair back. The chair back includes a lumbar support unit having a lumbar support pad that includes a plurality of support rings disposed one inside of the other.

Abstract: An office chair is provided having a back assembly which is configured to provide supplemental support to the back of a chair occupant in addition to the support provided by the primary support surface of the chair back. The chair back includes a lumbar support unit having a lumbar support pad wherein asymmetric support is provided to the left and right halves of the lumbar pad. As such, the asymmetric support loads are independently adjustable to more comfortably support a chair occupant. The chair back also includes a pelvic support pad which is disposed vertically adjacent to the lumbar support.

Abstract: An office chair is provided having a back assembly which is configured to provide supplemental support to the back of a chair occupant in addition to the support provided by the primary support surface of the chair back. The chair back includes a lumbar support unit having a lumbar support pad wherein asymmetric support is provided to the left and right halves of the lumbar pad. As such, the asymmetric support loads are independently adjustable to more comfortably support a chair occupant. The chair back also includes a pelvic support pad which is disposed vertically adjacent to the lumbar support.

Abstract: An office chair is provided having a back assembly which is configured to provide supplemental support to the back of a chair occupant in addition to the support provided by the primary support surface of the chair back. The chair back includes a lumbar support unit having a lumbar support pad wherein asymmetric support is provided to the left and right halves of the lumbar pad. As such, the asymmetric support loads are independently adjustable to more comfortably support a chair occupant. The chair back also includes a pelvic support pad which is disposed vertically adjacent to the lumbar support.

Abstract: An armrest for a chair is provided which has an improved anti-rotation and mechanical connection between an armrest body and a frame tube of the chair. The end of the frame tube is mechanically deformed or is shaped so as to have a non-circular profile with a central opening defined by inwardly projecting arcuate surfaces of the frame tube. The armrest includes a cooperating, non-circular socket which fits onto the frame tube wherein a suitable fastener is threaded downwardly into direct, self-threading engagement with an upper opening formed in the end of the frame tube.

Abstract: An armrest for a chair is provided which has an improved anti-rotation and mechanical connection between an armrest body and a frame tube of the chair. The end of the frame tube is mechanically deformed or is shaped so as to have a non-circular profile with a central opening defined by inwardly projecting arcuate surfaces of the frame tube. The armrest includes a cooperating, non-circular socket which fits onto the frame tube wherein a suitable fastener is threaded downwardly into direct, self-threading engagement with an upper opening formed in the end of the frame tube.

Abstract: An office chair (10) is provided-having a contoured back assembly (24) comprising a back frame (23) and a suspension fabric (26). The fabric is attached to the back frame through a spline (58) wherein the back frame has a three-dimensional contoured shape formed by overlapped frame rings with the fabric being joined thereto by a spline. The back frame has a split upright section to increase the ability of the left and right halves of the frame to articulate relative to each other. Further, a bayonet connection is provided between the back frame and a support upright which bayonet connection holds together the upper ends of two separate uprights of a tilt control mechanism.

Abstract: An office chair is provided having a back assembly which is configured to provide supplemental support to the back of a chair occupant in addition to the support provided by the primary support surface of the chair back. The chair back includes a lumbar support unit having a lumbar support pad wherein asymmetric support is provided to the left and right halves of the lumbar pad. As such, the asymmetric support loads are independently adjustable to more comfortably support a chair occupant. The chair back also includes a pelvic support pad which is disposed vertically adjacent to the lumbar support.

Abstract: An office chair is provided having a back assembly which is configured to provide supplemental support to the back of a chair occupant in addition to the support provided by the primary support surface of the chair back. The chair back includes a lumbar support unit having a lumbar support pad wherein asymmetric support is provided to the left and right halves of the lumbar pad. As such, the asymmetric support loads are independently adjustable to more comfortably support a chair occupant. The chair back also includes a pelvic support pad which is disposed vertically adjacent to the lumbar support.

Abstract: An office chair is provided having a back assembly which is configured to provide supplemental support to the back of a chair occupant in addition to the support provided by the primary support surface of the chair back. The chair back includes a lumbar support unit having a lumbar support pad wherein asymmetric support is provided to the left and right halves of the lumbar pad. As such, the asymmetric support loads are independently adjustable to more comfortably support a chair occupant. The chair back also includes a pelvic support pad which is disposed vertically adjacent to the lumbar support.

Abstract: An office chair is provided having a back assembly which is configured to provide supplemental support to the back of a chair occupant in addition to the support provided by the primary support surface of the chair back. The chair back includes a lumbar support unit having a lumbar support pad wherein asymmetric support is provided to the left and right halves of the lumbar pad. As such, the asymmetric support loads are independently adjustable to more comfortably support a chair occupant. The chair back also includes a pelvic support pad which is disposed vertically adjacent to the lumbar support.

Abstract: An office chair is provided having a back assembly which is configured to provide supplemental support to the back of a chair occupant in addition to the support provided by the primary support surface of the chair back. The chair back includes a lumbar support unit having a lumbar support pad wherein asymmetric support is provided to the left and right halves of the lumbar pad. As such, the asymmetric support loads are independently adjustable to more comfortably support a chair occupant. A testing apparatus and method are used to optimize the support pressure characteristics of the lumbar pad.

Abstract: An office chair is provided having a back assembly which is configured to provide supplemental support to the back of a chair occupant in addition to the support provided by the primary support surface of the chair back. The chair back includes a lumbar support unit having a lumbar support pad wherein asymmetric support is provided to the left and right halves of the lumbar pad. As such, the asymmetric support loads are independently adjustable to more comfortably support a chair occupant. A testing apparatus and method are used to optimize the support pressure characteristics of the lumbar pad.

Abstract: An office chair is provided having a back assembly which is configured to provide supplemental support to the back of a chair occupant in addition to the support provided by the primary support surface of the chair back. The chair back includes a lumbar support unit having a lumbar support pad wherein asymmetric support is provided to the left and right halves of the lumbar pad. As such, the asymmetric support loads are independently adjustable to more comfortably support a chair occupant. The chair back also includes a pelvic support pad which is disposed vertically adjacent to the lumbar support.

Abstract: A support arm for a chair includes a base component and a support body interconnected therewith wherein opposite ends of the support body are movable longitudinally and laterally. The opposite ends may be displaced simultaneously in opposite lateral directions to permit angular displacement of the support body. The connector arrangement which interconnects the support body to the base component includes two sets of locking formations wherein the first set include longitudinally elongate parallel slots and the second set include an array of lateral rows and longitudinal columns of openings. The holes define the lateral and longitudinal position of one end of the support body while the slots define the lateral position of the opposite end of the support body.

Abstract: A support arm for a chair includes a base component and a support body interconnected therewith wherein opposite ends of the support body are movable longitudinally and laterally. The opposite ends may be displaced simultaneously in opposite lateral directions to permit angular displacement of the support body. The connector arrangement which interconnects the support body to the base component includes two sets of locking formations wherein the first set include longitudinally elongate parallel slots and the second set include an array of lateral rows and longitudinal columns of openings. The holes define the lateral and longitudinal position of one end of the support body while the slots define the lateral position of the opposite end of the support body.