Passenger headrest height adjustment system
A vehicle headrest height adjustment system includes a vehicle seat having a seat back, a seat base and a headrest. A sensing device generates a signal when the vehicle seat is unoccupied by an occupant. A headrest displacement mechanism is connected to the headrest and reversibly displaces the headrest between a headrest extended position and a headrest retracted position. The headrest displacement mechanism lowers the headrest to the headrest retracted position when the signal is received from the sensing device that the vehicle seat is unoccupied by the occupant defined when the occupant is not present.
1 . A vehicle headrest height adjustment system, comprising:
a vehicle seat having a seat back, a seat base and a headrest;
a sensing device generating a signal when the vehicle seat is unoccupied by an occupant; and
a headrest displacement mechanism connected to the headrest and reversibly displacing the headrest between a headrest extended position and a headrest retracted position, the headrest displacement mechanism lowering the headrest to the headrest retracted position when the signal is received from the sensing device that the vehicle seat is unoccupied by the occupant,
wherein the headrest displacement mechanism includes a motor positioned within a housing located within the seat back, and at least one telescoping rod supports the headrest to the seat back and is connected to the motor thereby permitting telescoping motion of the headrest by operation of the motor, and
wherein the headrest displacement mechanism includes:
a threaded portion of the at least one telescoping rod;
a shaft sleeve extending from the motor into the at least one telescoping rod; and
a drive gear connected to the shaft sleeve engaging the threaded portion wherein operation of the motor rotates the drive gear and thereby the threaded portion initiates telescoping motion of the headrest.
2 . The vehicle headrest height adjustment system of claim 1 , wherein the sensing device defines a weight sensor supported by the seat base.
3 . The vehicle headrest height adjustment system of claim 1 , wherein the sensing device defines a camera.
4 . The vehicle headrest height adjustment system of claim 1 , wherein the sensing device defines a seatbelt latched sensor indicating the occupant is not present due to an un-latched condition of a passenger seatbelt.
5 . The vehicle headrest height adjustment system of claim 1 , further including a manual adjustment switch positioned proximate to the occupant and configured to be manually actuated by the occupant to change a position of the headrest.
6 . The vehicle headrest height adjustment system of claim 1 , wherein the headrest includes a concave portion which mimics and is oppositely facing with respect to a portion of the seat back having a convex-shape.
7 . A headrest height adjustment system, comprising:
a vehicle seat having a seat base, a seat back rotatably connected to the seat back and a headrest telescoping from the seat back;
a sensing device generating a signal if the vehicle seat is unoccupied by an occupant;
a first telescoping rod and a second telescoping rod connected to the headrest allowing the headrest to slidably move between a headrest extended position and a headrest retracted position;
a headrest displacement mechanism connected to the headrest and one of the first telescoping rod and the second telescoping rod, the headrest displacement mechanism automatically lowering the headrest to the headrest retracted position when the signal is received from the sensing device that the vehicle seat is unoccupied by the occupant defined when the occupant is not present, wherein the headrest displacement mechanism includes a motor, the motor being positioned in a housing which is fixed within the seat back;
a shaft connected to and axially rotated by operation of the motor, the shaft extending into a tubular cavity of one of the first telescoping rod and the second telescoping rod;
an inner wall of the one of the first telescoping rod and the second telescoping rod including a threaded portion facing into the tubular cavity; and
a drive gear fixed on the shaft and threadingly engaging the threaded portion.
8 . The headrest height adjustment system of claim 7 , including a shaft sleeve mounted to a surface of the seat back, the shaft passing through the shaft sleeve to retain a position and an orientation of the shaft while supporting axial rotation of the shaft.
9 . The headrest height adjustment system of claim 7 , wherein operation of the motor in a first operation rotates the shaft and thereby the drive gear which engages with the threaded portion to drive the one of the first telescoping rod and the second telescoping rod in an upward direction to displace the headrest to the headrest extended position.
10 . The headrest height adjustment system of claim 7 , wherein the drive gear defines one of a worm gear and a helical gear.
11 . The headrest height adjustment system of claim 7 , wherein the one of the first telescoping rod and the second telescoping rod includes a rod diameter which is smaller than an inner diameter of the housing, wherein the one of the first telescoping rod and the second telescoping rod slides into and out of the housing during operation of the motor.