Head rest device

• US 20060006709A1
• Filed: 06/09/2005
• Published: 01/12/2006
• Est. Priority Date: 07/02/2004
• Status: Active Grant

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Sano, Koji, Uno, Koji, Terauchi, Tatsuya
• Granted Patent: US 7,641,280 B2
• Time in Patent Office: Days
• US Class Current: 297/216.120
• CPC Class Codes: B60N 2/4228 due to impact coming from the rear
• CPC Class Codes: B60N 2/809 vertically slidable
• CPC Class Codes: B60N 2/888 with arrangements for protecting against abnormal g-forces, e.g. by displacement of the head-rest

Abstract

When a pressure receiving plate provided at a seat back moves to a rear side of a vehicle body when a vehicle is collided from behind, a Bowden cable transmits movement of the pressure receiving plate to a headrest ascending mechanism as a tensile load, thereby quickly ascending a headrest to reliably hold a head of an occupant. The Bowden cable transmits only the tensile load, and hence the Bowden cable is not buckled. Reduction in weight is made possible as compared with the case using a rod for transmitting a compression load. Since the Bowden cable is light, it is not required to unreasonably place the pressure receiving plate at a position near the headrest ascending mechanism for reduction in weight, and hence the pressure receiving plate can be placed at the optimal position where a sufficient driving force is obtained at the time of collision. Thus, a headrest is ascended with favorable responsiveness upon a rear-end collision of a vehicle while using a thin transmission member with low rigidity.

Claims

1. A headrest device comprising:

a headrest ascending mechanism which ascendably supports a headrest at an upper end of a seat back;

a pressure receiving plate which is provided at the seat back to face a back of an occupant and which moves to a rear side of a vehicle body by an inertia force upon a rear-end collision of a vehicle; and

transmission means which connects the pressure receiving plate to the headrest ascending mechanism and which operates the headrest ascending mechanism to ascend the headrest when the pressure receiving plate moves to the rear side of the vehicle body,

wherein the transmission means is a long member and transmits rearward movement of the pressure receiving plate to the headrest ascending mechanism as a tensile load.

2. The headrest device according to claim 1, wherein the transmission means is a Bowden cable.

3. The headrest device according to claim 2, wherein the Bowden cable extends from the pressure receiving plate to run upward in the seat back, and is then bent downward to be connected to the headrest ascending mechanism.

4. A seat back assembly comprising:

a seat back;

a headrest ascending mechanism secured to the seat back, said headrest ascending mechanism ascendably supporting a headrest at an upper end of a seat back;

a pressure receiving plate secured to the seat back and facing toward a back of an occupant, said pressure receiving plate moving to a rear side of a vehicle body by an inertia force upon a rear-end collision of a vehicle; and

transmission means connecting the pressure receiving plate to the headrest ascending mechanism, said transmission means being operable to cause the headrest ascending mechanism to ascend the headrest when the pressure receiving plate moves to the rear side of the vehicle body,

wherein the transmission means is a long member and transmits rearward movement of the pressure receiving plate to the headrest ascending mechanism as a tensile load.

5. The seat back assembly according to claim 4, wherein the transmission means is a Bowden cable.

6. The seat back assembly according to claim 5, wherein the Bowden cable extends from the pressure receiving plate to run upward in the seat back, and is then bent downward to be connected to the headrest ascending mechanism.

7. A method for raising a headrest upon a rear-end collision of a vehicle, comprising the steps of:

providing a seat back assembly comprising;

a seat back, said seat back including a pressure receiving plate, a headrest ascending mechanism, a force transmitting device, and a headrest, said pressure receiving plate facing toward a back of an occupant and being adapted to move rearwardly upon by an inertia force during the rear-end collision of the vehicle, said headrest ascending mechanism ascendably supporting the headrest at an upper end of a seat back, said force transmitting device operably connecting the pressure receiving plate to the headrest ascending mechanism and being operable to cause the headrest ascending mechanism to raise the headrest when the pressure receiving plate moves to the rear side of the vehicle body;

upon experiencing a rear-end collision, moving the pressure receiving plate rearwardly;

transmitting said movement of the pressure receiving plate via the force transmitting device, to the headrest ascending mechanism as a tensile load;

raising the headrest.

8. The method of claim 7, wherein the force transmitting device is a Bowden cable, and wherein the Bowden cable extends upwardly from the pressure receiving plate through the seat back, and is then bent downward to be connected to the headrest ascending mechanism.