Natural balance active chair

Abstract

A dynamic joint, to serve as part of a chair, where the dynamic joint is disposed between, and fixedly attached to, the seat and the base of the chair. The joint is operative to enable a person sitting on the chair to tilt the seat in any direction, over a substantial angle, by appropriate force from the person's pelvis and to similarly tilt the seat from any tilted position further in any direction. The Joint comprises a pair of attachment members and an elastomer body, structurally linked with them. The elastomer body is formed so as to include the tilting axes, close to the seat, and so as to control the dynamic tilting characteristics. Also provided is a chair, comprising said joint, and an ergonomic seat for the chair, enabling the person to sit safely and comfortably while tilting the seat. Configuration of the chair as an exercise device is described.

1 . A dynamic joint serving as part of a chair, the chair including a seat and a base, the joint being attachable to the seat and to the base and comprising:
 a rigid upper member, directly or indirectly attachable to the seat;   a rigid lower member, directly or indirectly attachable to the base; and   a single flexible member, solely disposed between said upper and lower members and fixedly attached thereto,   
       wherein said upper member is tiltable with respect to said lower member over a substantial tilt angle about a horizontal pivot axis locatable below the upper member and above the lower member. 
     
     
         2 . The joint as in  claim 1 , wherein said tilting is variable in at least one direction, said pivot axis definable by two orthogonal horizontal axes. 
     
     
         3 . The joint as in  claim 2 , wherein the direction of said tilting is dynamically varied. 
     
     
         4 . (canceled) 
     
     
         5 . The joint as in  claim 3 , wherein said flexible member is made of at least one elastomer and contacts said upper and lower members. 
     
     
         6 . The joint as in  claim 3 , wherein any of said rigid members is formed to interlock with said flexible member. 
     
     
         7 . The joint as in  claim 3 , wherein the structure of said flexible member is configured to affect, with respect to any tilting direction, one or more of—
 a force required to tilt said upper member, 
 a progressive variation of said force with the tilting angle and 
 a vertical location of said pivot axis. 
 
     
     
         8 . The joint as in  claim 3 , wherein said flexible member has a single circumferential surface, defining a waist, which has a diameter, in at least one vertical cross-section, and said surface further formed to have said waist positionable in a plurality of vertical cross-sections of a plurality of azimuthal directions. 
     
     
         9 . (canceled) 
     
     
         10 . The joint as in  claim 8 , wherein said diameter is generally variable with the azimuthal direction and said waist has a vertical location in a vertical cross-sectional plane, said vertical location defining a vertical position of the pivot axis when said joint is tiltable in the respective vertical cross-sectional plane, and said waist configurable in any vertical cross-sectional plane to affect a force required to tilt said upper member as a function of said tilt angle. 
     
     
         11 . (canceled) 
     
     
         12 . (canceled) 
     
     
         13 . The joint as in  claim 3 , wherein at least one of said rigid members is further formed so that a part thereof serves as an anchor within said flexible member. 
     
     
         14 . The joint as in  claim 13 , wherein said part that is formable as at least one plate having at least one face contacting corresponding portions of said flexible member. 
     
     
         15 . The joint as in  claim 14 , wherein at least one of said plates includes at least one hole therein, the at least one hole fillable with an elastomer forming an integral part of said flexible member. 
     
     
         16 . (canceled) 
     
     
         17 . (canceled) 
     
     
         18 . (canceled) 
     
     
         19 . (canceled) 
     
     
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         22 . (canceled) 
     
     
         23 . (canceled) 
     
     
         24 . (canceled) 
     
     
         25 . (canceled) 
     
     
         26 . An ergonomic seat, adapted to serve as part of a chair, wherein the seat is tiltable in at least one direction by a substantial tilt angle, the seat formable to arrest a person sitting thereon from sliding thereoff when the seat is tilted and to distribute the weight of the person substantially evenly when the seat is tilted and when not tilted. 
     
     
         27 . (canceled) 
     
     
         28 . (canceled) 
     
     
         29 . (canceled) 
     
     
         30 . (canceled) 
     
     
         31 . (canceled) 
     
     
         32 . (canceled) 
     
     
         33 . (canceled) 
     
     
         34 . (canceled)