Chair having tilting seat and back

Abstract

An ergonomic chair includes a support body having a seat support portion and a back support portion. A forward sloping seat track is positioned on the seat support portion. A first seat portion engages the seat track on the seat support portion for forward and rearward movement along the seat track between a forward position and a rearward position. A second seat portion is provided having an upwardly extending back rest. The second seat portion is pivotally connected to the first seat portion. Movement of the first seat portion forward along the seat track toward the forward position draws the second seat portion forward with forward movement of the second seat portion causing movement of the back rest downwardly. This allows for subtle movement forward and backward movement that energizes major leg muscles.

What is claimed is: 
     
         1 . A chair, comprising:
 a support body having a seat support portion and a back support portion;   a seat track on the seat support portion;   a first seat portion engaging the seat track on the seat support portion for forward and rearward movement along the seat track between a forward position and a rearward position;   a second seat portion engaging the seat track on the seat support portion for forward and rearward movement along the seat track, the second seat portion having an angularly fixed upwardly extending back rest;   at least one back rest track on one of the back support portion or a remote end of the back rest, and at least one track follower on another of the back support portion or the remote end of the back rest;   the second seat portion being pivotally connected to the first seat portion, such that movement of the first seat portion forward along the seat track toward the forward position draws the second seat portion forward with forward movement of the second seat portion causing movement of the back rest downwardly with such movement accommodated by cooperation of the at least one back rest track and the at least one track follower.   
     
     
         2 . The chair of  claim 1 , wherein the first seat portion is biased into the rearward position. 
     
     
         3 . The chair of  claim 1 , wherein the back rest track is linear. 
     
     
         4 . The chair of  claim 1 , wherein the seat track is arcuate. 
     
     
         5 . The chair of  claim 1 , wherein the first seat portion and the second seat portion share an overlying fabric covering. 
     
     
         6 . The chair of  claim 5 , wherein a portion of the overlying fabric covering the second seat portion having a friction inducing and pressure relieving profile. 
     
     
         7 . A chair, comprising:
 a support body having a seat support portion and a back support portion;   a forward sloping arcuate seat track on the seat support portion;   a first seat portion engaging the arcuate seat track on the seat support portion for forward and rearward movement along the arcuate seat track between a forward position and a rearward position;   a second seat portion engaging the arcuate seat track on the seat support portion for forward and rearward movement along the arcuate seat track, the second seat portion having an angularly fixed upwardly extending back rest;   the first seat portion and the second seat portion share an overlying fabric covering, a portion of the overlying fabric covering the second seat portion having a friction inducing and pressure relieving profile;   two linear back rest tracks on one of the back support portion or a remote upper end of the back rest, and a pair of track followers on another of the back support portion or the remote upper end of the back rest;   the second seat portion being pivotally connected to the first seat portion, such that when pressure is exerted to move first seat portion forward along the arcuate seat track toward the forward position the second seat portion is drawn forward with forward movement of the second seat portion causing movement of the back rest downwardly along the back rest track; and   the first seat portion being biased to the rearward position, such that the first seat portion returns to the rearward position when pressure is removed.