Magnetic sensor

• US 6,552,662 B1
• Filed: 08/26/2000
• Issued: 04/22/2003
• Est. Priority Date: 08/26/1999
• Status: Expired due to Fees

• Current Assignee: Automotive Systems Laboratory, Incorporated (Ningbo Junsheng Investment Group Co., Ltd.)
• Original Assignee: Automotive Systems Laboratory, Incorporated (Ningbo Junsheng Investment Group Co., Ltd.)
• Inventors: Bomya, Timothy J., Riggs, Alan J.
• Primary Examiner(s): Hofsass, Jeffery
• Assistant Examiner(s): Previl, Daniel
• Application Number:
  US09/648,528
• Time in Patent Office: 969 Days
• Field of Search: 340/572.1, 340/572.5, 340/572.6, 340/573.1, 340/554, 340/551, 340/438, 280/735
• US Class Current: 340/572.1
• CPC Class Codes: B60R 21/01532 using electric or capacitive field sensors
• CPC Class Codes: B60R 21/01534 using electromagneticwaves, e.g. infrared

Abstract

A magnetic sensor comprises at least one first coil operatively coupled to a first portion of a vehicle seat and at least one magnetic sensing element operatively coupled to an interior portion. At least one first signal is operatively connected to the at least one first coil, wherein the at least one first signal is an oscillating signal. At least one second signal responsive to the at least one first signal is sensed from the at least one magnetic sensing element, and an occupant is discriminated an occupant on the vehicle seat responsive to the second signal.

Claims

1. A magnetic sensor, comprising:

a. at least one first coil operatively coupled to a first portion of a vehicle seat;

b. at least one magnetic sensing element operatively coupled to an interior portion of said vehicle;

c. at least one first signal operatively connected to said at least one first coil, wherein said at least one first signal is an oscillating signal;

d. a means for sensing at least one second signal from said at least one magnetic sensing element, wherein said at least one second signal is responsive to said at least one first signal; and

e. a means for discriminating an occupant on said vehicle seat, wherein said means for discriminating is responsive to said second signal, and said second signal is responsive to an interaction of an occupant on said vehicle seat with a magnetic field generated by said at least one first coil responsive to said at least one first signal, when said occupant is seated on said vehicle seat.

2. A magnetic sensor as recited in claim 1, wherein said interior portion comprises a second portion of said vehicle seat.

3. A magnetic sensor as recited in claim 2, wherein said second portion of said vehicle seat comprises a seat back.

4. A magnetic sensor as recited in claim 2, wherein said second portion of said vehicle seat comprises a seat bottom.

5. A magnetic sensor as recited in claim 1, wherein said means for discriminating is responsive to a Doppler shift of said oscillatory signal.

6. A magnetic sensor as recited in claim 1, wherein said first portion of said vehicle seat comprises a seat bottom.

7. A magnetic sensor as recited in claim 6, wherein said at least one first coil comprises a coil around a substantial portion of said seat bottom.

8. A magnetic sensor as recited in claim 5, wherein said at least one first coil comprises a coil around a substantial portion of said seat bottom.

9. A magnetic sensor as recited in claim 1, wherein said at least one magnetic sensing element is selected from at least one coil and at least one Hall effect sensor.

10. A magnetic sensor as recited in claim 1, wherein said at least one magnetic sensing element comprises a plurality of magnetic sensing elements.

11. A magnetic sensor as recited in claim 10, wherein at least one of said plurality of magnetic sensing elements is proximate to a lower portion of a seat back of said vehicle seat, and at least another of said plurality of magnetic sensing elements is proximate to an upper portion of said seat back.

12. A magnetic sensor as recited in claim 11, wherein at least another of said plurality of magnetic sensing elements is proximate to a safety restraint actuator.

13. A magnetic sensor as recited in claim 10, wherein at least one of said plurality of magnetic sensing elements is proximate to a second portion of said vehicle seat, and at least another of said plurality of magnetic sensing elements is proximate to a safety restraint actuator.

14. A magnetic sensor as recited in claim 1, wherein said interior portion comprises a portion that is proximate to a safety restraint actuator.

15. A magnetic sensor as recited in claim 1, wherein said at least one first coil comprises a plurality of first coils.

16. A magnetic sensor as recited in claim 15, wherein said at least one first signal comprises a plurality of first signals, and at least one of said plurality of first signals is operatively connect to at least one first coil of said plurality of first coils and is phase encoded so as to be distinguished from at least another first signal applied to at least another of said plurality of first coils.

17. A magnetic sensor as recited in claim 15, wherein at least one of said plurality of first coils is proximate to a second portion of said vehicle seat, and at least another of said plurality of first coils is proximate to a safety restraint actuator.

18. A magnetic sensor as recited in claim 15, wherein at least one of said plurality of first coils is proximate to a lower portion of a seat back of said vehicle seat, and at least another of said plurality of first coils is proximate to an upper portion of said seat back.

19. A magnetic sensor as recited in claim 18, wherein at least another of said plurality of first coils is proximate to a safety restraint actuator.

20. A magnetic sensor as recited in claim 1, further comprising a safety restraint actuator operatively connected to said means for discriminating an occupant on said vehicle seat, wherein an actuation of said safety restraint actuator is at least partially controlled by said means for discriminating an occupant on said vehicle seat.

21. A method of sensing an occupant in a vehicle seat of a vehicle, comprising:

a. generating a magnetic flux at at least one first location in an interior of the vehicle so that said magnetic flux extends into a region of space bounded by a seat bottom and a seat back of the vehicle seat, wherein said region of space is at least partially occupied by an occupant on the vehicle seat when said occupant is seated on said vehicle seat;

b. conducting said magnetic flux to at least one second location in said interior of the vehicle;

c. sensing said magnetic flux at said at least one second location;

d. generating at least one signal responsive to said magnetic flux sensed at said at least one second location, wherein said at least one signal is responsive to an interaction of an occupant on said vehicle seat with said magnetic field, when said occupant is seated on said vehicle seat; and

e. discriminating an occupant when said occupant is seated on said vehicle seat wherein said operation of discriminating is responsive to said at least one signal.

22. A method of sensing an occupant in a vehicle seat of a vehicle as recited in claim 21, wherein at least one said at least one first location is within a first portion of said vehicle seat.

23. A method of sensing an occupant in a vehicle seat of a vehicle as recited in claim 22, wherein at least one said at least one second location is within a second portion of said vehicle seat.

24. A method of sensing an occupant in a vehicle seat of a vehicle as recited in claim 21, wherein at least one of said at least one first location and said at least one second location is proximate to a safety restraint actuator.

25. A method of sensing an occupant in a vehicle seat of a vehicle as recited in claim 21, wherein said at least one first location comprises a plurality of first locations.

26. A method of sensing an occupant in a vehicle seat of a vehicle as recited in claim 25, wherein at least one of said plurality of first locations is proximate to an upper portion of a seat back of said vehicle seat and at least another of said plurality of first locations is proximate to a lower portion of said seat back of said vehicle seat.

27. A method of sensing an occupant in a vehicle seat of a vehicle as recited in claim 25, further comprising modulating at least one phase of said magnetic flux, wherein a phase of said magnetic flux generated at at least one location of said plurality of first locations is different from a phase of said magnetic flux generated at at least another location of said plurality of first locations.

28. A method of sensing an occupant in a vehicle seat of a vehicle as recited in claim 21, wherein said least one second location comprises a plurality of second locations.

29. A method of sensing an occupant in a vehicle seat of a vehicle as recited in claim 28, wherein at least one of said plurality of second locations is proximate to an upper portion of a seat back of said vehicle seat and at least another of said plurality of second locations is proximate to a lower portion of said seat back of said vehicle seat.

30. A method of sensing an occupant in a vehicle seat of a vehicle as recited in claim 21, further comprising controlling the actuation of a safety restraint actuator so as to protect said occupant when the vehicle is involved in a crash, wherein the operation of controlling the actuation of a safety restraint actuator is responsive to said operation of discriminating.