Patent attributes
A seat for a vehicle includes a seat back frame, a first elastic member, and a second elastic member. The seat back frame includes a main frame and a sub-frame. The first elastic member and the second elastic member are configured to support the sub-frame such that the sub-frame is rotatable in a width direction of the seat and are mounted between the main frame and upper end portions of the sub-frame on both sides in the width direction of the seat. Each of the first elastic member and the second elastic member has a limit of elongation and has a characteristic in which a load that is applied to the sub-frame in a rear direction of the seat acts as tension to generate a reaction force due to the limit of elongation and does not generate the reaction force in the width direction of the seat.
