Headrest apparatus, method of adjusting headrest position, vehicle seat

1. A headrest apparatus comprising:

a headrest main body provided at a top edge portion of a seatback against which the back of an occupant seated in a seat rests, with the headrest main body provided so as to be capable of moving in a vehicle front-rear direction;

a detection section provided at a vehicle front side of the headrest main body to detect contact between the head of an occupant seated in the seat and the headrest main body;

a moving section that moves the headrest main body in the vehicle front-rear direction; and

a controller that controls the moving section such that the headrest main body is moved forward until contact between the head of an occupant and the headrest main body is detected by the detection section, and, when contact between the head of an occupant and the headrest main body has been detected by the detection section, controls the moving section to move the headrest main body to a target position, wherein a movement amount of the headrest main body from an initial position thereof to the target position is given by subtracting a predetermined back-set setting value from a movement amount of the headrest main body from the initial position to a position where the headrest main body has contacted the head of the occupant.

2. The headrest apparatus of claim 1 , wherein:

the headrest main body is also movable in a height direction; and

the controller only moves the headrest main body to the target position when the height direction position of the headrest main body is in a predetermined range of appropriate positions.

3. The headrest apparatus of claim 1 , wherein:

the headrest main body is also movable in a height direction;

the moving section also moves the headrest main body in the height direction;

the detection section is provided spanning the height direction of the headrest main body and detects the height direction contact position between the head of an occupant and the headrest main body; and

the controller controls the moving section to move the headrest main body to the target position, and moves the headrest main body upwards or downwards by an amount at misalignment between the height direction contact position detected by the detection section and a predetermined height direction specific position for the headrest main body.

4. The headrest apparatus of claim 1 , wherein:

the controller controls the moving section such that the headrest main body is moved so that contact between the head of an occupant and the headrest main body is detected by the detection section a plurality of times, and controls the moving section so as to move the headrest main body to the target position after movement amounts of the headrest main body from the control start position to points of contact have converged.

5. The headrest apparatus of claim 3 , wherein:

the controller controls the moving section such that the headrest main body is moved so that contact between the head of an occupant and the headrest main body is detected by the detection section a plurality of times, and controls the moving section so as to move the headrest main body to the target position after the detected height direction contact positions have converged.

6. The headrest apparatus of claim 1 , wherein:

the detection section detects a strength of contact between the head of an occupant and the headrest main body; and

the controller moves the headrest main body to the target position when the strength of contact detected by the detection section is a predetermined specific strength or less.

7. The headrest apparatus of claim 1 , wherein:

the headrest main body is provided with a headrest rear section supported at the top edge portion of the seatback and a headrest front section that is configured so as to be capable of approaching towards and separating from the headrest rear section, and to be capable of moving in the vehicle front-rear direction between a fully closed position where the headrest front section is closest to the headrest rear section and a fully open position where the headrest front section is furthest away from the headrest rear section;

the detection section is provided at the vehicle front side of the headrest front section; and

the moving section moves the headrest main body in the vehicle front-rear direction such that the headrest front section moves between the fully open position and the fully closed position.

8. A method of adjusting headrest position, the method comprising:

moving a headrest main body forward with a moving section, the headrest main body being provided at a top edge portion of a seatback against which the back of an occupant seated in a seat rests and being provided so as to be capable of moving in a vehicle front-rear direction;

detecting contact between the head of an occupant seated in the seat and the headrest main body with a detection section provided at the vehicle front side of the headrest main body; and

moving the headrest main body with a moving section to a target position, wherein a movement amount of the headrest main body from an initial position thereof to the target position is given by subtracting a predetermined back-set setting value from a movement amount of the headrest main body from the initial position to a position where the headrest main body has contacted the head of the occupant.

9. A vehicle seat provided with the headrest apparatus of claim 1 .

10. A headrest apparatus comprising:

a headrest main body provided at a top edge portion of a seatback which is configured to accommodate the back of an occupant seated in a seat;

a contact detection unit provided at a vehicle front side of the headrest main body configured to detect a contact between the head of the occupant seated in the seat and the headrest main body;

a driving mechanism configured to move the headrest main body to-and-fro in substantially vehicle front-rear directions; and

a headrest control unit configured to control movement of the headrest main body,

wherein the headrest control unit is configured to move the headrest main body toward the front in the vehicle front-rear direction until a contact between the head of the occupant and the headrest main body is detected by the contact detection unit and to move the headrest main body toward the rear in the vehicle front rear direction to a target position, wherein a movement amount of the headrest main body from an initial position thereof to the target position is given by subtracting a predetermined back-set setting value from a movement amount of the headrest main body from the initial position to a position where the headrest main body has contacted the head of the occupant.

11. The headrest apparatus of claim 1 , wherein:

the headrest main body is further configured to move in a height direction; and

the headrest control unit is further configured to move the headrest main body only when the height direction position of the headrest main body is in a predetermined range of positions.

12. The headrest apparatus of claim 1 , wherein:

the headrest apparatus further comprises a vertical drive mechanism to move the headrest main body to-and-fro substantially in vertical direction when said seatback is substantially in up-right position;

the contact detection unit is further configured to detect the height direction contact position between the head of the occupant and the headrest main body; and

the headrest control unit is further configured to move the headrest main body upwards or downwards to compensate misalignment between the height direction contact position detected by the detection section and a predetermined height direction specific position for the headrest main body.

13. The headrest apparatus of claim 1 , wherein the headrest control unit is configured to move the headrest main body from an initial position toward the front in the vehicle front-rear direction until a contact between the head of the occupant and the headrest main body is detected by the contact detection unit a plurality of times, and

to move the headrest main body toward the rear in the vehicle front rear direction the specific amount from the contact position when a variance among each movement amount of the headrest main body is within a specific value.

14. The headrest apparatus of claim 3 , wherein the headrest control unit is configured to move the headrest main body from an initial position toward the front in the vehicle front-rear direction until a contact between the head of the occupant and the headrest main body is detected by the contact detection unit a plurality of times, and

to move the headrest main body toward the rear in the vehicle front rear direction a specific amount from the contact position when a variance among each movement amount of the headrest main body is within a specific value.

15. The headrest apparatus of claim 1 , wherein the contact detection unit is configured to detects a strength of contact between the head of the occupant and the headrest main body; and

the headrest control unit is configured to move the headrest main body when the strength of contact detected by the contact detection unit is a predetermined specific strength or less.

16. The headrest apparatus of claim 1 , wherein:

the headrest main body comprises a rear section and a front section,

the contact detection unit is provided at the vehicle front side of the headrest front section, and

the driving mechanism is configured to move the front section to-and-fro so that the front section moves between a fully closed position where the headrest front section is closest to the headrest rear section and a fully open position where the headrest front section is furthest away from the headrest rear section.