Abstract: A striker is supported by and coupled to a seat body and is held in a rotated position where the striker is lowered to a position along the shape of the seat body. When the seat body is moved and stowed, the striker is raised to and held at a rotated and raised position where the striker can be engaged and locked to a locking device. Elasticity of an opening spring and a rubber body, which are arranged between the striker and a coupling section, allows a forced rotational displacement of the striker in both forward and reverse directions from a state in which the striker is held at the rotated and raised position.

Abstract: A striker is supported by and coupled to a seat body and is held in a rotated position where the striker is lowered to a position along the shape of the seat body. When the seat body is moved and stowed, the striker is raised to and held at a rotated and raised position where the striker can be engaged and locked to a locking device. Elasticity of an opening spring and a rubber body, which are arranged between the striker and a coupling section, allows a forced rotational displacement of the striker in both forward and reverse directions from a state in which the striker is held at the rotated and raised position.

Abstract: The upper frame 3 and a pair of the side frames 5 in the frame body 2 are simultaneously formed by bending the first frame plate 20 which is obtained from a raw flat plate by pressing treatment. And the upper frame 3 is formed into a pipe form having a slit 6 with edge portions and the slit 6 is welded at four positions corresponding to the bending portions 3B and the concave portions 9 in the horizontal portion 3C, thereby the slit connecting portions 10 are formed. Accordingly, based on that main members for constructing the seat back frame 1 are formed from the first flat frame plate 20, number of the members for constructing the seat back frame 1 and process number for assembling thereof can be easily reduced.