CHAIR WITH BACKWARD AND FORWARD PASSIVE TILT CAPABILITIES

摘要

A chair with backward and forward passive tilt capabilities including a seatassembly, a back assembly, a frame assembly, a wheeled base, a pedestal and atilt mechanism. The tilt mechanism includes first, second and third links,first, second, third and fourth pivot pins, brackets and a resilientdeformable block. The first link connects the back assembly with the frameassembly by way of the first pivot pin and the seat assembly by way of thesecond pivot pin. The second link connects to the frame assembly with thethird pivot pin and to the third link with the fourth pivot pin. When a chairoccupant shifts his/her weight rearwardly to tilt the back assembly, the seatassembly lifts and the block is deformed and stressed. When the chair occupantleans forwardly, the seat assembly lowers and the back assembly tiltsforwardly. Again, the block deforms. Once the occupant sits upright or leavesthe chair, the deformed block induces a return force to place the chair in aneutral upright position.