Abstract: A lumbar support operation member comprising a shaft attachment portion that is configured so as to be fixed to a rotation shaft that transmits rotation force to a moving mechanism of a lumbar support provided to a seatback and that is positioned at a side portion of the seatback; and operation portions that are provided at an radial direction outside of the shaft attachment portion, that are separated from each other in a circumferential direction of the shaft attachment portion, and that make the shaft attachment portion rotate.

Abstract: A lumbar support operation member comprising a shaft attachment portion that is configured so as to be fixed to a rotation shaft that transmits rotation force to a moving mechanism of a lumbar support provided to a seatback and that is positioned at a side portion of the seatback; and operation portions that are provided at an radial direction outside of the shaft attachment portion, that are separated from each other in a circumferential direction of the shaft attachment portion, and that make the shaft attachment portion rotate.

Abstract: A seat device comprises a cushion frame mounted on a floor; a support member for supporting a seat pad; and torsion bars for elastically supporting the support member on the cushion frame, including a torque bar section and an arm section, wherein the torsion bars are provided at the front and rear positions of the seat or at the left and right positions thereof by at least one pair, and each arm section of the at least one pair of torsion bars be provided so as to form a parallel link mechanism.

Abstract: A seat device has a cushion frame mounted on a floor; a support member for supporting a seat pad; and a torsion bar including a torque bar section and an arm section, for elastically supporting the support member on cushion frame. An arm supporting bracket of substantially cylindrical shape is provided on the support member. A collar rotatably fitted to at least arm supporting bracket has a circumferential flange in a cylindrical shape with a bottom, and is disposed to be facing to an end surface of the arm supporting bracket on the opening side thereof. A tip portion of the arm section is fittedly supported in the opening of the collar. The arm supporting bracket is attached to the support member through a movement absorbing mechanism which allows relative movement with respect to the support member.

Abstract: A supporting member in a conventional seat device is supported only by torsion bar arm portions positioned at right and left sides of the device. Accordingly, when a large biased load acts on the device, a sufficient roll rigidity is not obtained and both arm portions at the right and left sides rotate simultaneously. Interference with the supporting panel, cushion frame or the like may also occur. Accordingly, a seat pad supporting member supported by a cushion frame provided on a floor is elastically supported on at least one of the front and rear portions thereof to a torsion frame by a torsion bar. The torsion bar is latched, at the torsion bar torque bar portion side, to the cushion frame side. The torsion arm portion side, moreover, is latched to the right and left sides. Finally, the torsion bar arm portion, on both sides, is connected to a connecting member.