Abstract: To promote bloodstream and reduce fatigue, a seat structure makes a slight sitting posture change by adding a minute body motion with no necessity of moving a cushion frame or a seat frame although it realizes a supporting pressure change at a wide area, not locally, in a seat cushion or a seat back. The seat structure includes a cushioning member for a seat cushion stretched across the cushion frame, and a cushioning member for a seat back stretched across the back frame. The seat structure includes: a lower cloth spring of a seat cushion or a cloth spring of a seat back stretched across the cushion frame or the back frame via a torsion bar; and a cloth spring adjusting member to change a supporting pressure by both cushioning members by adjusting tension of the lower cloth spring or the cloth spring.

Abstract: A mechanism for mounting a seat belt of a center seating space of a vehicle seat which exhibits sufficient strength and reduces weight and production costs to the greatest degree is provided. Such a mechanism is provided by separating a seat into a right seating section and a left seating section at the center thereof such that each of the separated seating sections is independently slidable back and forth by means of a seat sliding rail formed of a pair of lower rails fixed to a floor side and a pair of upper rails fixed to the bottom of a seat. A base member bent at an intermediate bent portion defined by a belt mount plate portion and a rail mount connector portion is attached to a side surface of the inner upper rail at the rail connector plate portion such that the belt mount plate portion extends outward. An anchor for the seat belt of the center seating space of the seat is fixed to the top end of the belt mount plate portion of the base member.