DEVICE FOR ADJUSTING POSITION OF HEADREST AND METHOD FOR ADJUSTING POSITION OF HEADREST

• US 20120041648A1
• Filed: 03/10/2010
• Published: 02/16/2012
• Est. Priority Date: 03/10/2009
• Status: Abandoned Application

• Current Assignee: Fujikura Limited
• Original Assignee: Fujikura Limited
• Inventors: Yamaguchi, Yuichiro, Noguchi, Yuki, Osaki, Takuya, Sakurai, Ryohei
• Application Number:
  US13/255,394
• Publication Number:
  US 20120041648A1
• Time in Patent Office: Days
• US Class Current: 701/49
• CPC Class Codes: B60N 2/002 Seats provided with an occupancy detection means mounted therein or thereon detection means responsive to presence or absence of children B60N2/266
• CPC Class Codes: B60N 2/0268 using sensors or detectors for adapting the seat or seat part, e.g. to the position of an occupant
• CPC Class Codes: B60N 2/853 characterised by their adjusting mechanisms, e.g. electric motors
• CPC Class Codes: B60N 2/888 with arrangements for protecting against abnormal g-forces, e.g. by displacement of the head-rest

Abstract

To automatically adjust a position of a headrest accurately by preventing an unnecessary movement of the headrest, a headrest position adjusting device includes a sensing electrode 1 and a detecting circuit 2 embedded in a headrest 13 provided on a seat 10, an arithmetic circuit 5, a headrest driving motor 3, and a motor control circuit 4. The arithmetic circuit 5 calculates the distance between the head 22 of an occupant 21 and the headrest 13 and an amount of change of a capacitance based on a capacitance value from the detecting circuit 2. The motor control circuit 4 controls the headrest driving motor 3 in accordance with the calculation results to adjust the position of the headrest 13. When a vehicle signal from a vehicle signal output unit 6 is a specific signal or when the amount of change of the capacitance per a predetermined time is larger than a certain threshold, the arithmetic circuit 5 outputs to the motor control circuit 4 a calculation result for suspending the position adjusting operation for the headrest 13.

Claims

1. A headrest position adjusting device, comprising:

at least one sensing electrode provided in a headrest provided on a seat of a vehicle for sensing a capacitance between a head of a human body sitting on the seat and the headrest;

a detecting circuit which detects a capacitance value based on the capacitance from the sensing electrode;

vehicle signal output means which outputs a vehicle signal regarding at least one of an operation to the vehicle and a state of the seat; and

position adjusting means which receives the vehicle signal output by the vehicle signal output means, calculates a distance between the head and the headrest and an amount of change of the capacitance based on the capacitance value detected by the detecting circuit, and in accordance with calculation results, adjusts a position of the headrest by moving the headrest to an appropriate position based on the distance and a position of the head,

wherein the position adjusting means suspends a position adjusting operation for the headrest for a predetermined time, when one of the following cases occurs;

a case when the vehicle signal output by the vehicle signal output means is a specific signal indicating a specific state; and

a case when the vehicle signal indicates that the amount of change, per a predetermined time, of the capacitance from the detecting circuit is larger than a certain threshold.

2. The headrest position adjusting device according to claim 1,

wherein when one of the cases for suspending the position adjusting operation for the headrest for the predetermined time occurs, after the predetermined time has passed, the position adjusting means resumes the position adjusting operation for the headrest in accordance with the calculation results.

3. The headrest position adjusting device according to claim 1,

wherein the specific signal is any one of an instruction operation signal regarding a left or right turn of the vehicle, an operation signal to an instrument panel of the vehicle, an operation signal to a vehicle-mounted device mounted on the vehicle, an instruction operation signal regarding a brake of the vehicle, a reversing instruction operation signal to a shift lever of the vehicle, a parking instruction operation signal to the shift lever of the vehicle, an operation signal regarding opening/closing of a door of the vehicle, an operation signal regarding opening/closing of a window of the vehicle, an operation signal to a console box of the vehicle, an operation signal to a glove compartment of the vehicle, and a signal regarding presence or absence of sitting of a human body on the seat.

4. A headrest position adjusting method for adjusting a position of a headrest provided on a seat of a vehicle by moving the headrest to an appropriate position in accordance with a distance between a head and the headrest and a position of the head based on a capacitance value which is based on a capacitance from at least one sensing electrode provided in the headrest and a vehicle signal regarding at least one of an operation to the vehicle and a state of the seat, the method comprising:

a calculating step of calculating based on the capacitance value, a distance between a head of a human body sitting on the seat and the headrest and an amount of change of the capacitance;

a judging step of judging based on the vehicle signal whether or not the vehicle signal is a specific signal indicating a specific state;

a controlling step of controlling moving of the headrest in accordance with calculation results of the calculating step and a judgment result of the judging step,

wherein the controlling step executes a control of suspending a position adjusting operation for the headrest for a predetermined time, when one of the following cases occurs;

a case when the judgment result of the judging step indicates that the vehicle signal is a specific signal; and

a case when the calculation result of the calculating step indicates that the amount of change, per a predetermined time, of the capacitance from a detecting circuit is larger than a certain threshold.

5. The headrest position adjusting method according to claim 4,

wherein when one of the cases for suspending the position adjusting operation for the headrest for the predetermined time occurs, after the predetermined time has passed, the controlling step executes a control of resuming the position adjusting operation for the headrest in accordance with the calculation results.

6. The headrest position adjusting method according to claim 4,

wherein the specific signal is any one of an instruction operation signal regarding a left or right turn of the vehicle, an operation signal to an instrument panel of the vehicle, an operation signal to a vehicle-mounted device mounted on the vehicle, an instruction operation signal regarding a brake of the vehicle, a reversing instruction operation signal to a shift lever of the vehicle, a parking instruction operation signal to the shift lever of the vehicle, an operation signal regarding opening/closing of a door of the vehicle, an operation signal regarding opening/closing of a window of the vehicle, an operation signal to a console box of the vehicle, an operation signal to a glove compartment of the vehicle, and a signal regarding presence or absence of sitting of a human body on the seat.

7. A headrest position adjusting device, comprising:

at least one sensing electrode provided in a headrest provided on a seat of a vehicle for sensing a capacitance between a head of a human body sitting on the seat and the headrest;

a detecting circuit which detects a capacitance value based on the capacitance from the sensing electrode;

vehicle signal output means which outputs at least a vehicle speed signal regarding a speed of the vehicle as a vehicle signal; and

position adjusting means which receives the vehicle signal output by the vehicle signal output means, calculates a distance between the head and the headrest and an amount of change of the capacitance based on the capacitance value detected by the detecting circuit, and in accordance with calculation results, adjusts a position of the headrest by moving the headrest to an appropriate position based on the distance and a position of the head,

wherein the position adjusting means starts a position adjusting operation by moving the headrest, when the vehicle signal output by the vehicle signal output means indicates at least that the vehicle has come to move forward at a certain speed or higher.

8. The headrest position adjusting device according to claim 7,

wherein the vehicle signal output means outputs a signal indicating presence or absence of sitting on the seat as the vehicle signal, and

when the seat is other than a driver seat of the vehicle, the position adjusting means starts a position adjusting operation for the headrest on that seat when the vehicle signal additionally indicates that sitting on the seat is present.

9. The headrest position adjusting device according to claim 7,

wherein the vehicle signal output means outputs a signal regarding an ignition switch of the vehicle and a signal indicating fastening/unfastening of a seatbelt sent from a seatbelt buckle of the seat as the vehicle signal, and

the position adjusting means starts a position adjusting operation for the headrest when the vehicle signal additionally indicates that the ignition switch is ON and that the seatbelt is fastened.

10. The headrest position adjusting device according to claim 7,

wherein when the amount of change, per a predetermined time, of the capacitance from the detecting circuit is larger than a certain threshold, the position adjusting means does not start a position adjusting operation for the headrest.

11. A headrest position adjusting method for adjusting a position of a headrest provided on a seat of a vehicle by moving the headrest to an appropriate position in accordance with a distance between a head and the headrest and a position of the head based on a capacitance value which is based on a capacitance from at least one sensing electrode provided in the headrest and at least a vehicle speed signal as a vehicle signal regarding a speed of the vehicle, the method comprising:

a calculating step of calculating a distance between a head of a human body sitting on the seat and the headrest and an amount of change of the capacitance;

a vehicle signal receiving step of receiving the vehicle signal; and

a controlling step of controlling moving of the headrest based on calculation results of the calculating step and the vehicle signal received by the vehicle signal receiving step,

wherein the controlling step executes a control of starting a position adjusting operation by moving the headrest, when the vehicle signal received by the vehicle signal receiving step indicates at least that the vehicle has come to move forward at a certain speed or higher.

12. The headrest position adjusting method according to claim 11,

wherein the vehicle signal receiving step receives a signal indicating presence or absence of sitting on the seat as the vehicle signal, and

when the seat is other than a driver seat of the vehicle, the controlling step executes a control of starting a position adjusting operation for the headrest on that seat when the vehicle signal additionally indicates that sitting on the seat is present.

13. The headrest position adjusting method according to claim 11,

wherein the vehicle signal receiving step receives a signal regarding an ignition switch of the vehicle and a signal indicating fastening/unfastening of a seatbelt sent from a seatbelt buckle of the seat as the vehicle signal, and

the controlling step executes a control of starting a position adjusting operation for the headrest when the vehicle signal additionally indicates that the ignition switch is ON and that the seatbelt is fastened.

14. The headrest position adjusting method according to claim 11,

wherein the controlling step executes a control of refraining from starting a position adjusting operation for the headrest when the calculation result indicates that the amount of change, per a predetermined time, of the capacitance from a detecting circuit is larger than a certain threshold.