HEADREST HEIGHT ADJUSTING APPARATUS

Abstract

A headrest height adjusting apparatus includes: a basal member attached to a seatback and supporting a driving member; a movable member linked to a headrest and lifted up and down relative to the basal member; a transmitting member transmitting a driving force of the driving member to the movable member and lifting up and down the headrest linked to the movable member. The transmitting member having a frangible portion that leads a collapse of the transmitting member against an impact applied in a vertical direction between the driving member and the movable member and absorbs energy of the impact.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and additional features and characteristics of the present invention will become more apparent from the following detailed description considered with reference to the accompanying drawings, wherein:

FIG. 1 is a perspective view illustrating a seat for a vehicle to which an embodiment of the present invention is applied;

FIG. 2 is a front view illustrating the seat having a headrest height adjusting apparatus;

FIG. 3 is a front view illustrating the headrest height adjusting apparatus;

FIG. 4 is a sectional view taken along line IV-IV in FIG. 3;

FIG. 5 is an exploded perspective view illustrating the headrest height adjusting apparatus; and

FIG. 6A is a front view illustrating an operation of a bush of the headrest height adjusting apparatus; and

FIG. 6B is another front view illustrating the operation of the bush.

Claims

1. A headrest height adjusting apparatus comprising: a basal member attached to a seatback and supporting a driving member;a movable member linked to a headrest and lifted up and down relative to the basal member; anda transmitting member transmitting a driving force of the driving member to the movable member and lifting up and down the headrest linked to the movable member, the transmitting member having a frangible portion that leads a collapse of the transmitting member in response to an impact applied in a vertical direction between the driving member and the movable member and absorbs energy of the impact.

2. A headrest height adjusting apparatus according to claim 1, wherein the transmitting member further includes: a body part, which is engaged with an input member of the movable member and transmits driving force of the driving member to the input member; and a metal-made core, which is inserted into the body part and faces the input member in the vertical direction.

3. A headrest height adjusting apparatus according to claim 2, the body part is made of resin having elasticity.

4. A headrest height adjusting apparatus according to claim 2, wherein the body part includes an insert hole, into which the core is inserted, and an outer peripheral portion that is engaged with the input member, and the frangible portion is an extension that extends in a radial direction and connects the insert hole and the outer peripheral portion.

5. A headrest height adjusting apparatus according to claim 3, wherein the body part includes an insert hole, into which the core is inserted, and an outer peripheral portion that is engaged with the input member, and the frangible portion is an extension that extends in a radial direction and connects the insert hole and the outer peripheral portion.

6. A headrest height adjusting apparatus according to claim 1, wherein the driving member includes a driving source and a rotational member, which is rotatably supported by the basal member and is rotatably operated by the driving source, and the transmitting member is a sliding member, which is connected to the rotational member and is arranged at a long hole formed at the movable member, the sliding member converts a rotational movement of the rotational member to a linear movement while sliding on the long hole so that the headrest linked to the movable member is lifted up and down.

7. A headrest height adjusting apparatus according to claim 2, wherein the driving member includes a driving source and a rotational member, which is rotatably supported by the basal member and is rotatably operated by the driving source, and the transmitting member is a sliding member, which is connected to the rotational member and is arranged at a long hole formed at the movable member, the sliding member converts a rotational movement of the rotational member to a linear movement while sliding on the long hole so that the headrest linked to the movable member is lifted up and down.

8. A headrest height adjusting apparatus according to claim 3, wherein the driving member includes a driving source and a rotational member, which is rotatably supported by the basal member and is rotatably operated by the driving source, and the transmitting member is a sliding member, which is connected to the rotational member and is arranged at a long hole formed at the movable member, the sliding member converts a rotational movement of the rotational member to a linear movement while sliding on the long hole so that the headrest linked to the movable member is lifted up and down.

9. A headrest height adjusting apparatus according to claim 4, wherein the driving member includes a driving source and a rotational member, which is rotatably supported by the basal member and is rotatably operated by the driving source, and the transmitting member is a sliding member, which is connected to the rotational member and is arranged at a long hole formed at the movable member, the sliding member converts a rotational movement of the rotational member to a linear movement while sliding on the long hole so that the headrest linked to the movable member is lifted up and down.

10. A headrest height adjusting apparatus according to claim 5, wherein the driving member includes a driving source and a rotational member, which is rotatably supported by the basal member and is rotatably operated by the driving source, and the transmitting member is a sliding member, which is connected to the rotational member and is arranged at a long hole formed at the movable member, the sliding member converts a rotational movement of the rotational member to a linear movement while sliding on the long hole so that the headrest linked to the movable member is lifted up and down.

11. A headrest height adjusting apparatus according to claim 1, further comprising: a supporting member supporting the movable member when the transmitting member collapses.