Patent ID: 8899681

Claim:
A seat guiding apparatus for a chair, comprising: a base having two guiding portions at two opposite sides thereof, each of the guiding portions extending curvedly from a rear end of the base toward a front end of the base and being provided with a curved guiding groove; an elastic assembly having a shaft fastened to the front end of the base, a moveable plate pivotally connected with the shaft, and a torsion spring mounted on the shaft and provided with two distal ends stopped against a bottom of the moveable plate; a seat assembly having a seat and a bracket connected with a bottom of the seat, the bracket having a front end connected with the moveable plate, and a rear end provided with two opposite lug portions respectively connected with the guiding portions of the base through a pin inserted into each of the curved guiding grooves, such that the seat assembly is pivotable around the shaft and movable along the curved guiding grooves relative to the base; and an elasticity adjusting assembly including a swivel member pivotally mounted in the base and provided with an abutting portion abutted against a U-shaped portion of the torsion spring, a screw rod rotatably inserted into the base through an elongated slot of the swivel member, a knob mounted with one end of the screw rod for driving the screw rod to rotate, and a press block screwed onto the screw rod and located on the swivel member so as to be driven by the screw rod to press the swivel member.