Abstract: A speed reduction mechanism comprises a drive member rotated by a rotary drive force of a drive source; a fixed member opposing to the drive member; a rotor disposed between the drive member and the fixed member and contacting the drive member and the fixed member and rotated around itself by the rotation of the drive member and revoluted around a rotary central portion of the drive member; and a speed reduction rotary member for rotatably supporting the rotor and rotated around the rotary central portion of the drive member by the revolution of the rotor.

Abstract: To turn a seat to a reverse position within a narrow space, a rotary seat is composed of a turntable, a thigh support frame, a hip support cushion disposed on the turntable, and a thigh support cushion disposed on the thigh support frame. Simultaneously when the thigh support frame is pivoted upwardly from an original position together with the thigh support cushion, a latch mechanism is released via a latch releasing mechanism, and the turntable and the thigh support frame become rotatable with the thigh support cushion remaining pivoted upwardly. The turntable is then latched into a reversed position when the thigh support frame is pivoted back down to the original position.

Abstract: A seat for motor vehicle includes a seat cushion whose rear or front section or both are coupled via a link mechanism with a base frame in a manner that can be lifted and lowered, whereby through joining of the link mechanism to a control shaft for height adjustment that can be rotated without any limitation, coupling of one of the rocking ends of a bell crank which repeats a rocking motion, interlocked with the rotation of the control shaft, to the seat cushion, and joining of the other rocking end to the control shaft via a crank, it is possible to adjust the height of the rear section, front section, or both, of the cushion seat between the lowest position and the highest position, for every rocking operation of the bell crank.