A vehicle seat hinge assembly including a base plate, a seat support assembly, and an off-center hinge. The base plate is configured to mount to a vehicle and the seat support assembly is configured to mount to the seat. The off-center hinge of the vehicle seat hinge assembly is positioned at one corner of the base plate and pivotally couples at least part of the seat support assembly to the base plate. The base plate has a base plate centerline and the off-center hinge has a hinge axis that is arranged at an oblique angle relative to the base plate centerline.

A vehicle seat structure includes: a first side frame (11a) extending in a front-rear direction along one side portion of a seat cushion (4); a second side frame (11b) extending in the front-rear direction along the other side portion of the seat cushion (4); posture changing mechanisms (6, 7) mounted on the first side frame (11a) and capable of changing the posture of the seat cushion (4), and reinforcement members (R1, R2) provided at a portion of the second side frame (11b) where the reinforcement members (R1, R2) overlap the posture changing mechanisms (6, 7) in a side view.

A vehicle seat structure includes: a first side frame (11a) extending in a front-rear direction along one side portion of a seat cushion (4); a second side frame (11b) extending in the front-rear direction along the other side portion of the seat cushion (4); posture changing mechanisms (6, 7) mounted on the first side frame (11a) and capable of changing the posture of the seat cushion (4), and reinforcement members (R1, R2) provided at a portion of the second side frame (11b) where the reinforcement members (R1, R2) overlap the posture changing mechanisms (6, 7) in a side view.

Provided is a vehicle seat that facilitates setting of a starting load of a movable member. The vehicle seat includes a movable mechanism including: first and second springs coupled to a frame; a movable member displaceable relative to the frame; a first passive member and a second passive member coupled with the respective first and second springs; and a restriction member configured to restrict displacement of the first and second passive members. The movable member displaces the first passive member in a first direction when the movable member is displaced in the first direction, and displaces the second passive member in a second direction when the movable member is displaced in the second direction. The restriction member restricts displacement of the first passive member from a first-passive-member initial position in the second direction and displacement of the second passive member from a second-passive-member initial position in the first direction.

A headrest is supported by an upper lateral member and a lower lateral member of a seat frame. A headrest stay is inserted through each of guide slots, both of which are formed in both the upper lateral member and the lower lateral member, and an extension wire is hooked on a lower end of the headrest stay. In a rear-collision, a seat back is retreated by a force received from a seated passenger, and a tension of the tension wire is accordingly loosened, which causes the headrest to be tilted forward by an urging force of tilt springs.

In the vehicle seat, rear suspension members are provided at two positions spaced away from each other in a lateral direction on an edge of a seat cushion near a seatback, and support the seat cushion while the seat cushion is suspended from a seat cushion support frame so that the seat cushion is movable in the lateral direction. A front suspension member is provided at one position or two positions spaced away from each other in the lateral direction on ahead of the rear suspension members, and supports the seat cushion while the seat cushion is suspended from the seat cushion support frame so that the seat cushion is movable in the lateral direction.

Provided is a seating-system kit for a vehicle that comprises floor beams, a primary pair of seat tracks, attached to the floor beams, and a first seat assembly, comprising a first seat support and a first plurality of seats, attached to the first seat support. The first seat support is attached to the primary pair of seat tracks and the floor beams support floor panels that define a floor surface. The vehicle has a virtual longitudinal plane, perpendicular to the floor surface, and a virtual longitudinal axis, parallel to the floor surface and lying in the virtual longitudinal plane. The seating-system kit comprises a secondary pair of seat tracks and a second seat assembly, comprising a second seat support and a second plurality of seats, attached to the second seat support, and wherein the second seat support is configured to be attached to the secondary pair of seat tracks.

A seat cushion is swingable about an axis A with respect to a seat cushion support frame that is a part of a main frame. A cushion return spring that is a flat spring is disposed between the seat cushion and the seat cushion support frame so that an elastic force of the cushion return spring returns the seat cushion to a neutral position. A pair of clamp rollers that clamps the cushion return spring is disposed. The clamp rollers are movable along a longitudinal axis of the cushion return spring. Changing of a clamping position by moving the clamp rollers changes an effective length of the cushion return spring. In this way, a swingable range of the seat cushion and a force to return the seat cushion to the neutral position are changed.

A vehicle seat includes a lock-to-neutral-position mechanism that locks a seat cushion at a neutral position, and an immediate lock mechanism that locks the seat cushion immediately at a current position when locking is required. A steering sensor senses a steering angle and a steering angular velocity. The immediate lock mechanism performs the locking when the steering angle is large, whereas the lock-to-neutral-position mechanism performs the locking when the steering velocity is high. When the steering wheel is at the neutral position, the locking by the immediate lock mechanism is released and the locking is switched over to the lock-to-neutral-position mechanism that is in a lock ready state.

A locking block is fixed with respect to a seat cushion. A locking pin which can advance and retract relative to the locking block is provided on a main frame side. A V groove shape receptacle is formed on the locking block. When the locking pin is advanced into the receptacle portion, the locking pin is guided by a receiving inclined surface of the receptacle portion forming the V-shape groove, and advances to a bottom of the receptacle portion. With this process, the locking block moves in a rotational direction B, and when the locking pin engages the bottom, the seat cushion is fixed.