A height adjustment mechanism for a headrest includes: a locking member configured to be locked with a height adjustment gear, the locking member having a first locking position and a first unlocking position, and the locking member being capable of switching between the first locking position and the first unlocking position; an operating member having an initial position, a first operating position and a second operating position; a safety lock structure configured to lock the locking member in the first locking position, the safety lock structure being movably connected on the operating member; and a driving member, one side of the driving member being slidably connected to the operating member, the other side of the driving member abutting against the locking member.

A height adjustment mechanism for a headrest includes: a locking member configured to be locked with a height adjustment gear, the locking member having a first locking position and a first unlocking position, and the locking member being capable of switching between the first locking position and the first unlocking position; an operating member having an initial position, a first operating position and a second operating position; a safety lock structure configured to lock the locking member in the first locking position, the safety lock structure being movably connected on the operating member; and a driving member, one side of the driving member being slidably connected to the operating member, the other side of the driving member abutting against the locking member.

A vehicle seat headrest has a first sub-piece facing a seat occupant head, a second sub-piece and an energy storage device with a trigger actuator arranged between the first sub-piece and the second sub-piece. The first sub-piece is moveable relative to the second sub-piece out of a use position into a safety position along a movement direction towards the a seat occupant head as a result of an accident under the effect of a discharge of the energy storage device, which is actuated by the trigger actuator. The headrest is configured such that the volume of an expansion area is increased while the first sub-piece is moved relative to the second sub-piece as a result of an accident and by the effect of the discharge of the energy storage device. The headrest has a sealing device between the first sub-piece and the second sub-piece to delimit the expansion area.

A vehicle seat headrest has a first sub-piece facing a seat occupant head, a second sub-piece and an energy storage device with a trigger actuator arranged between the first sub-piece and the second sub-piece. The first sub-piece is moveable relative to the second sub-piece out of a use position into a safety position along a movement direction towards the a seat occupant head as a result of an accident under the effect of a discharge of the energy storage device, which is actuated by the trigger actuator. The headrest is configured such that the volume of an expansion area is increased while the first sub-piece is moved relative to the second sub-piece as a result of an accident and by the effect of the discharge of the energy storage device. The headrest has a sealing device between the first sub-piece and the second sub-piece to delimit the expansion area.

A vehicle occupant protection device includes a vehicle seat, a steering wheel, a steering moving mechanism, and a control unit. The vehicle seat includes a seat back and a headrest, the vehicle seat being configured to turn between a position where the vehicle seat is directed toward a vehicle front side and a position where the vehicle seat is directed toward a vehicle rear side. The steering wheel is provided ahead of the vehicle seat in a vehicle front-rear direction. The steering moving mechanism is configured to change a position of the steering wheel. The control unit is configured to move the steering wheel to a support position where the seat back and the headrest are supported by the steering wheel from the vehicle front side, by the steering moving mechanism, when the vehicle seat is directed toward the vehicle rear side.

A vehicle occupant protection device includes a vehicle seat, a steering wheel, a steering moving mechanism, and a control unit. The vehicle seat includes a seat back and a headrest, the vehicle seat being configured to turn between a position where the vehicle seat is directed toward a vehicle front side and a position where the vehicle seat is directed toward a vehicle rear side. The steering wheel is provided ahead of the vehicle seat in a vehicle front-rear direction. The steering moving mechanism is configured to change a position of the steering wheel. The control unit is configured to move the steering wheel to a support position where the seat back and the headrest are supported by the steering wheel from the vehicle front side, by the steering moving mechanism, when the vehicle seat is directed toward the vehicle rear side.

A headrest may be fixed relative to a seat or a bank of seats in a vehicle and can provide multiple stages of deformation in response to a collision event. The headrest can include a resilient member that deforms in response to a first force caused by the collision event. The headrest can also include a frame that deforms in a first manner in response to a second force greater than the first force and in a second manner in response to a third force greater than the second force. Such a headrest can provide improved impact mitigation for occupants, regardless of height and/or weight such that occupants ranging from the 5.sup.th to 95.sup.th percentile in height and/or weight are afforded similar impact mitigation despite a fixed headrest structure. In some examples, multiple such headrests may be conjoined.

A headrest may be fixed relative to a seat or a bank of seats in a vehicle and can provide multiple stages of deformation in response to a collision event. The headrest can include a resilient member that deforms in response to a first force caused by the collision event. The headrest can also include a frame that deforms in a first manner in response to a second force greater than the first force and in a second manner in response to a third force greater than the second force. Such a headrest can provide improved impact mitigation for occupants, regardless of height and/or weight such that occupants ranging from the 5.sup.th to 95.sup.th percentile in height and/or weight are afforded similar impact mitigation despite a fixed headrest structure. In some examples, multiple such headrests may be conjoined.

A vehicle seat attachable to a vehicle body, the vehicle seat including: a seat back; and a headrest configured to support a head of a seated occupant, the headrest including: a base portion fixed to the seat back; a slide portion slidable in a left-right direction in a state where the head is supported to the base portion; and an electric mechanism configured to slide the slide portion in the left-right direction, and in which the slide portion is configured to be moved by the electric mechanism in a moving direction in which the head moves in the left-right direction due to acceleration in the left-right direction applied when a vehicle moves, the electric mechanism being operated by a control device disposed in the vehicle body in response to a signal from a sensor disposed in the vehicle body, the sensor being configured to detect the moving direction.

A vehicle seat attachable to a vehicle body, the vehicle seat including: a seat back; and a headrest configured to support a head of a seated occupant, the headrest including: a base portion fixed to the seat back; a slide portion slidable in a left-right direction in a state where the head is supported to the base portion; and an electric mechanism configured to slide the slide portion in the left-right direction, and in which the slide portion is configured to be moved by the electric mechanism in a moving direction in which the head moves in the left-right direction due to acceleration in the left-right direction applied when a vehicle moves, the electric mechanism being operated by a control device disposed in the vehicle body in response to a signal from a sensor disposed in the vehicle body, the sensor being configured to detect the moving direction.