Abstract: In a front part inside a seat cushion are arranged a catching member extending in a widthwise direction of the seat cushion and movable up and down, and inertial force transmission means for moving the catching member upward by the inertial force that acts on an inertial mass at the time of rapid deceleration. When a passenger sits on the seat cushion, the catching member moves down so as not to deteriorate the seat comfort, and at the time of rapid deceleration, the catching member moves up and stops the passenger's hips from moving forward. Thus it is reliably prevented that the passenger moves forward, without deteriorating the seat comfort, and the design is simple, lightweight, and low-cost.

Abstract: In a front part inside a seat cushion are arranged a catching member extending in a widthwise direction of the seat cushion and movable up and down, and inertial force transmission means for moving the catching member upward by the inertial force that acts on an inertial mass at the time of rapid deceleration. When a passenger sits on the seat cushion, the catching member moves down so as not to deteriorate the seat comfort, and at the time of rapid deceleration, the catching member moves up and stops the passenger's hips from moving forward. Thus it is reliably prevented that the passenger moves forward, without deteriorating the seat comfort, and the design is simple, lightweight, and low-cost.

Abstract: A catch member (14) extending in the width direction of a seat cushion (1) is arranged inside a front portion of the seat cushion (1) and is supported so as to be vertically movable. There are also provided a torsion spring (16) for urging the catch member (14) to move upward and a pendulum member (18) for operating with an inertial force upon an abrupt deceleration to inhibit vertical movement of the catch part. When a passenger sits on the seat cushion (1), the catch member (14) moves downward to preclude deterioration in seating comfort. When the passenger's rear end (22) starts to move forward upon an abrupt deceleration, the catch member (14) is locked and the rear end (22) is caught by the catch member (14). This makes it possible to suppressed the forward movement of the passenger with reliability, and allow lightweight and low-cost configuration with simple configuration.

Abstract: A catch member (14) extending in the width direction of a seat cushion (1) is arranged inside a front portion of the seat cushion (1) and is supported so as to be vertically movable. There are also provided a torsion spring (16) for urging the catch member (14) to move upward and a pendulum member (18) for operating with an inertial force upon an abrupt deceleration to inhibit vertical movement of the catch part. When a passenger sits on the seat cushion (1), the catch member (14) moves downward to preclude deterioration in seating comfort. When the passenger's rear end (22) starts to move forward upon an abrupt deceleration, the catch member (14) is locked and the rear end (22) is caught by the catch member (14). This makes it possible to suppressed the forward movement of the passenger with reliability, and allow lightweight and low-cost configuration with simple configuration.