Patent ID: 7322653

Claim:
A chair suitable for use with a videogaming and computer workstation, comprising: a vertically adjustable undercarriage; a tiltable seat attached to the undercarriage; and a tiltable backrest attached to the undercarriage and movable independently of the seat; whereby the seat is adapted to be raised and lowered by a user seated in the chair, and whereby the undercarriage is adapted to cause the seat to be tilted backward and forward in association with the backrest as the backrest is tilted backward and forward; the undercarriage further including a tilting mechanism for tilting a chair frame and the seat, whereby when the backrest is tilted backward, the seat is moved forward, a back end of the seat is tilted downward over a first distance and a front end of the seat is tilted downward over a second distance, and when the backrest is tilted forward, the seat is moved backward, the back end of the seat is tilted upward over the first distance and the front end of the seat is tilted upward over the second distance; and in which the tilting mechanism comprises: a shaft fixedly attached to the undercarriage; the chair frame pivotally attached to the shaft, the chair frame adapted to mount the backrest; a bracket fixedly attached to the shaft, the bracket supporting first and second pivot points; biasing means attached between the first pivot point of the bracket and the chair frame; a first see-saw link pivotally attached to the shaft and having first and second pivot points at opposite ends thereof; a second see-saw link pivotally attached to the second pivot point of the bracket and having first and second pivot points at opposite ends thereof, the first pivot point being pivotally attached to the first pivot point of the first see-saw link; an upright link having first and second pivot points at opposite ends thereof, the first pivot point of the upright link being pivotally attached to the chair frame and slidably attached to the second pivot point of the second see-saw link; and a seat support having front and back pivot points, the back pivot point pivotally attached to the second pivot point of the upright link, and the front pivot point being pivotally attached to the second pivot point of the first see-saw link.