Occupant sensor

• US 20010045733A1
• Filed: 05/29/2001
• Published: 11/29/2001
• Est. Priority Date: 05/26/2000
• Status: Active Grant

• Current Assignee: Joyson Safety Systems Acquisition, LLC
• Original Assignee: Automotive Systems Laboratory, Incorporated (Ningbo Junsheng Investment Group Co., Ltd.)
• Inventors: Stanley, James Gregory, Campbell, James A., McDonnell, Judson G.
• Granted Patent: US 6,703,845 B2
• Time in Patent Office: Days
• US Class Current: 280/735
• 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 2/28 Seats readily mountable on, and dismountable from, existing seats or other parts of the vehicle
• CPC Class Codes: B60N 2/286 forward facing B60N2/2866 takes precedence
• CPC Class Codes: B60N 2/2863 backward facing
• CPC Class Codes: B60N 2/5685 Resistance
• CPC Class Codes: B60R 21/01532 using electric or capacitive field sensors
• CPC Class Codes: B60R 21/0154 in combination with seat heating
• CPC Class Codes: G01V 3/088 operating with electric fields G01V3/082 takes precedence
• CPC Class Codes: H03K 17/955 using a capacitive detector

Abstract

An oscillatory or pulsed first signal is applied to a seat heating element that is operatively connected to first and second impedances that isolate the first signal from the source and sink of power to the heating element. In another embodiment, third and fourth impedances are connected to the first an second impedances at respective nodes, and a second signal substantially equal to the first signal is operatively coupled to the nodes. In another embodiment, the first signal is applied to an electrode, and the second signal is applied to the heating element, which shields the electrode from influence by the seat. In another embodiment, the first signal is applied to a first electrode that is shielded from the heating element by a second electrode operatively coupled to the second signal. The impedances may, for example, be provided by inductors or electronic switches.

Claims

1. A method of providing for sensing an occupant in a seat, wherein said seat incorporates a conductive heating element, said method comprising:

a) providing for operatively connecting a first impedance between a first node of said heating element and a source of power;

b) providing for operatively connecting a second impedance between a second node of said heating element and a sink of said power, wherein when a current is caused to flow between said first and second nodes by said source of power, said heating element generates heat;

c) placing an electrode at a location either between said heating element and a seating region of said seat, or adjacent to said heating element;

d) providing for operatively coupling a first signal to said electrode; and

e) providing for operatively coupling a second signal to said heating element at a location at or between said first and second nodes, wherein said first signal is an oscillating or pulsed signal, said second signal is substantially equal to said first signal, said first impedance is or is made to be substantially greater responsive to said first signal than responsive to a signal causing said current, and said second impedance is or is made to be substantially greater responsive to said first signal than responsive to said signal causing said current.

2. A method of providing for sensing an occupant in a seat as recited in

claim 1

, wherein at least one of said first and second impedances is provided by at least one of respective first and second inductors.

3. A method of providing for sensing an occupant in a seat as recited in

claim 1

, wherein at least one of said first and second impedances is provided by at least one of respective first and second electronic switches.

4. A method of providing for sensing an occupant in a seat as recited in

claim 3

, further comprising providing for operatively coupling said second signal to at least one location selected from a control input of said first electronic switch and a control input of said second electronic switch.

18. A method of providing for sensing an occupant in a seat as recited in

claim 1

, wherein said operation of operatively coupling said first signal comprises AC coupling.

22. A method of providing for sensing an occupant in a seat as recited in

claim 1

, wherein said operation of operatively coupling said second signal comprises AC coupling.

26. A method of providing for sensing an occupant in a seat as recited in

claim 1

, further comprising providing for sensing the occupant from a response to said first signal.

5. A method of providing for sensing an occupant in a seat, wherein said seat incorporates a conductive heating element, said method comprising:

a) placing a first electrode between said heating element and a seating region of said seat;

b) placing a second electrode between said heating element and said first electrode;

c) providing for operatively coupling a first signal to said first electrode; and

d) providing for operatively coupling a second signal to said second electrode, wherein said first signal is an oscillating or pulsed signal, and said second signal is substantially equal to said first signal.

6. A method of providing for sensing an occupant in a seat as recited in

claim 5

, further comprising:

a) placing an electrode on a side of said heating element away from a seating region of said seat; and

b) providing for operatively coupling a second signal to said electrode, wherein said second signal is substantially equal to said first signal.

7. A method of providing for sensing an occupant in a seat as recited in

claim 5

, wherein said second electrode comprises a sheath at least partially around at least a portion of said heating element.

19. A method of providing for sensing an occupant in a seat as recited in

claim 5

, wherein said operation of operatively coupling said first signal comprises AC coupling.

23. A method of providing for sensing an occupant in a seat as recited in

claim 5

, wherein said operation of operatively coupling said second signal comprises AC coupling.

27. A method of providing for sensing an occupant in a seat as recited in

claim 5

, further comprising providing for sensing the occupant from a response to said first signal.

8. A method of providing for sensing an occupant in a seat, wherein said seat incorporates a conductive heating element, said method comprising:

a) providing for operatively connecting a first impedance between a first node of said heating element and a source of power;

b) providing for operatively connecting a second impedance between a second node of said heating element and a sink of said power, wherein when a current is caused to flow between said first and second nodes by said source of power, said heating element generates heat, and at least one of said first and second impedances is provided by at least one of respective first and second inductors; and

c) providing for operatively coupling a first signal to said heating element at a location at or between said first and second nodes, wherein said first signal is an oscillating or pulsed signal, said first impedance is or is made to be substantially greater responsive to said first signal than responsive to a signal causing said current, and said second impedance is or is made to be substantially greater responsive to said first signal than responsive to said signal causing said current.

9. A method of providing for sensing an occupant in a seat as recited in

claim 8

, further comprising:

a) placing an electrode on a side of said heating element away from a seating region of said seat; and

b) providing for operatively coupling a second signal to said electrode, wherein said second signal is substantially equal to said first signal.

20. A method of providing for sensing an occupant in a seat as recited in

claim 8

, wherein said operation of operatively coupling said first signal comprises AC coupling.

24. A method of providing for sensing an occupant in a seat as recited in

claim 9

, wherein said operation of operatively coupling said second signal comprises AC coupling.

28. A method of providing for sensing an occupant in a seat as recited in

claim 8

, further comprising providing for sensing the occupant from a response to said first signal.

10. A method of providing for sensing an occupant in a seat, wherein said seat incorporates a conductive heating element, said method comprising:

a) providing for operatively connecting a first impedance between a first node of said heating element and a source of power;

b) providing for operatively connecting a second impedance between a second node of said heating element and a sink of said power;

c) providing for operatively connecting a third impedance between said first impedance and said source of power;

d) providing for operatively connecting a fourth impedance between said second impedance and said sink of power, wherein when a current is caused to flow between said first and second nodes by said source of power, said heating element generates heat;

e) providing for operatively coupling a first signal to said heating element at a location at or between said first and second nodes; and

f) providing for operatively coupling a second signal to at least one location selected from a third node between said first and third impedances and a fourth node between said second and fourth impedances, wherein said first signal is an oscillating or pulsed signal, said second signal is substantially equal to said first signal, said first impedance is or is made to be substantially greater responsive to said first signal than responsive to a signal causing said current, said second impedance is or is made to be substantially greater responsive to said first signal than responsive to said signal causing said current, said third impedance is or is made to be substantially greater responsive to said first signal than responsive to a signal causing said current, and said fourth impedance is or is made to be substantially greater responsive to said first signal than responsive to said signal causing said current.

11. A method of providing for sensing an occupant in a seat as recited in

claim 10

, wherein at least one of said first and second impedances is provided by at least one of respective first and second inductors.

12. A method of providing for sensing an occupant in a seat as recited in

claim 11

, wherein at least one of said third and fourth impedances is provided by at least one of respective third and fourth inductors.

13. A method of providing for sensing an occupant in a seat as recited in

claim 11

, wherein at least one of said third and fourth impedances is provided by at least one of respective third and fourth electronic switches.

14. A method of providing for sensing an occupant in a seat as recited in

claim 10

, wherein at least one of said first and second impedances is provided by at least one of respective first and second electronic switches.

15. A method of providing for sensing an occupant in a seat as recited in

claim 14

, further comprising providing for operatively coupling said second signal to at least one location selected from a control input of said first electronic switch and a control input of said second electronic switch.

16. A method of providing for sensing an occupant in a seat as recited in

claim 14

, wherein at least one of said third and fourth impedances is provided by at least one of respective third and fourth inductors.

17. A method of providing for sensing an occupant in a seat as recited in

claim 14

, wherein at least one of said third and fourth impedances is provided by at least one of respective third and fourth electronic switches.

21. A method of providing for sensing an occupant in a seat as recited in

claim 10

, wherein said operation of operatively coupling said first signal comprises AC coupling.

25. A method of providing for sensing an occupant in a seat as recited in

claim 10

, wherein said operation of operatively coupling said second signal comprises AC coupling.

29. A method of providing for sensing an occupant in a seat as recited in

claim 10

, further comprising providing for sensing the occupant from a response to said first signal.

30. A method of sensing an occupant in a seat, wherein said seat incorporates a conductive heating element, said method comprising:

a) operatively connecting a first impedance between a first node of said heating element and a source of power;

b) operatively connecting a second impedance between a second node of said heating element and a sink of said power, wherein when a current is caused to flow between said first and second nodes by said source of power, said heating element generates heat;

c) placing an electrode at a location either between said heating element and a seating region of said seat, or adjacent to said heating element;

d) operatively coupling a first signal to said electrode;

e) operatively coupling a second signal to said heating element at a location at or between said first and second nodes, wherein said first signal is an oscillating or pulsed signal, said second signal is substantially equal to said first signal, said first impedance is or is made to be substantially greater responsive to said first signal than responsive to a signal causing said current, and said second impedance is or is made to be substantially greater responsive to said first signal than responsive to said signal causing said current; and

f) sensing a response to said first signal.

31. A method of sensing an occupant in a seat as recited in

claim 30

, wherein at least one of said first and second impedances is provided by at least one of respective first and second inductors.

32. A method of sensing an occupant in a seat as recited in

claim 30

, wherein at least one of said first and second impedances is provided by at least one of respective first and second electronic switches.

33. A method of sensing an occupant in a seat as recited in

claim 32

, further comprising operatively coupling said second signal to at least one location selected from a control input of said first electronic switch and a control input of said second electronic switch.

47. A method of sensing an occupant in a seat as recited in

claim 30

, wherein said operation of operatively coupling said first signal comprises AC coupling.

51. A method of sensing an occupant in a seat as recited in

claim 30

, wherein said operation of operatively coupling said second signal comprises AC coupling.

55. A method of sensing an occupant in a seat as recited in

claim 30

, further comprising controlling the actuation of a safety restraint system responsive to said response to said first signal.

34. A method of sensing an occupant in a seat, wherein said seat incorporates a conductive heating element, said method comprising:

a) placing a first electrode between said heating element and a seating region of said seat;

b) placing a second electrode between said heating element and said first electrode;

c) operatively coupling a first signal to said first electrode;

d) operatively coupling a second signal to said second electrode, wherein said first signal is an oscillating or pulsed signal, and said second signal is substantially equal to said first signal; and

e) sensing a response to said first signal.

35. A method of sensing an occupant in a seat as recited in

claim 34

, further comprising:

f) placing an electrode on a side of said heating element away from a seating region of said seat; and

g) operatively coupling a second signal to said electrode, wherein said second signal is substantially equal to said first signal.

36. A method of sensing an occupant in a seat as recited in

claim 34

, wherein said second electrode comprises a sheath at least partially around at least a portion of said heating element.

48. A method of sensing an occupant in a seat as recited in

claim 34

, wherein said operation of operatively coupling said first signal comprises AC coupling.

52. A method of sensing an occupant in a seat as recited in

claim 34

, wherein said operation of operatively coupling said second signal comprises AC coupling.

56. A method of sensing an occupant in a seat as recited in

claim 34

, further comprising controlling the actuation of a safety restraint system responsive to said response to said first signal.

37. A method of sensing an occupant in a seat, wherein said seat incorporates a conductive heating element, said method comprising:

a) operatively connecting a first impedance between a first node of said heating element and a source of power;

b) operatively connecting a second impedance between a second node of said heating element and a sink of said power, wherein when a current is caused to flow between said first and second nodes by said source of power, said heating element generates heat, and at least one of said first and second impedances is provided by at least one of respective first and second inductors;

c) operatively coupling a first signal to said heating element at a location at or between said first and second nodes, wherein said first signal is an oscillating or pulsed signal, said first impedance is or is made to be substantially greater responsive to said first signal than responsive to a signal causing said current, and said second impedance is or is made to be substantially greater responsive to said first signal than responsive to said signal causing said current; and

d) sensing a response to said first signal.

38. A method of sensing an occupant in a seat as recited in

claim 37

, further comprising:

a) placing an electrode on a side of said heating element away from a seating region of said seat; and

b) operatively coupling a second signal to said electrode, wherein said second signal is substantially equal to said first signal.

49. A method of sensing an occupant in a seat as recited in

claim 37

, wherein said operation of operatively coupling said first signal comprises AC coupling.

53. A method of sensing an occupant in a seat as recited in

claim 38

, wherein said operation of operatively coupling said second signal comprises AC coupling.

57. A method of sensing an occupant in a seat as recited in

claim 37

, further comprising controlling the actuation of a safety restraint system responsive to said response to said first signal.

39. A method of sensing an occupant in a seat, wherein said seat incorporates a conductive heating element, said method comprising:

a) operatively connecting a first impedance between a first node of said heating element and a source of power;

b) operatively connecting a second impedance between a second node of said heating element and a sink of said power;

c) operatively connecting a third impedance between said first impedance and said source of power;

d) operatively connecting a fourth impedance between said second impedance and said sink of power, wherein when a current is caused to flow between said first and second nodes by said source of power, said heating element generates heat;

e) operatively coupling a first signal to said heating element at a location at or between said first and second nodes;

f) operatively coupling a second signal to at least one location selected from a third node between said first and third impedances and a fourth node between said second and fourth impedances, wherein said first signal is an oscillating or pulsed signal, said second signal is substantially equal to said first signal, said first impedance is or is made to be substantially greater responsive to said first signal than responsive to a signal causing said current, said second impedance is or is made to be substantially greater responsive to said first signal than responsive to said signal causing said current, said third impedance is or is made to be substantially greater responsive to said first signal than responsive to a signal causing said current, and said fourth impedance is or is made to be substantially greater responsive to said first signal than responsive to said signal causing said current; and

g) sensing a response to said first signal.

40. A method of sensing an occupant in a seat as recited in

claim 39

, wherein at least one of said first and second impedances is provided by at least one of respective first and second inductors.

41. A method of sensing an occupant in a seat as recited in

claim 40

, wherein at least one of said third and fourth impedances is provided by at least one of respective third and fourth inductors.

42. A method of sensing an occupant in a seat as recited in

claim 40

, wherein at least one of said third and fourth impedances is provided by at least one of respective third and fourth electronic switches.

43. A method of sensing an occupant in a seat as recited in

claim 39

, wherein at least one of said first and second impedances is provided by at least one of respective first and second electronic switches.

44. A method of sensing an occupant in a seat as recited in

claim 43

, further comprising operatively coupling said second signal to at least one location selected from a control input of said first electronic switch and a control input of said second electronic switch.

45. A method of sensing an occupant in a seat as recited in

claim 43

, wherein at least one of said third and fourth impedances is provided by at least one of respective third and fourth inductors.

46. A method of sensing-an occupant in a seat as recited in

claim 43

, wherein at least one of said third and fourth impedances is provided by at least one of respective third and fourth electronic switches.

50. A method of sensing an occupant in a seat as recited in

claim 39

, wherein said operation of operatively coupling said first signal comprises AC coupling.

54. A method of sensing an occupant in a seat as recited in

claim 39

, wherein said operation of operatively coupling said second signal comprises AC coupling.

58. A method of sensing an occupant in a seat as recited in

claim 39

, further comprising controlling the actuation of a safety restraint system responsive to said response to said first signal.

59. An occupant sensor for sensing an occupant in a seat, wherein said seat incorporates a conductive heating element, said occupant sensor comprising:

a) a first impedance operatively connecting a first node of said heating element to a source of power;

b) a second impedance operatively connecting a second node of said heating element to a sink of said power, wherein when a current is caused to flow between said first and second nodes by said source of power, said heating element generates heat;

c) an electrode located either between said heating element and a seating region of said seat, or adjacent to said heating element;

d) a first signal operatively coupled to said electrode; and

e) a second signal operatively coupled to said heating element at a location at or between said first and second nodes, wherein said first signal is an oscillating or pulsed signal, said second signal is substantially equal to said first signal, said first impedance is or is made to be substantially greater responsive to said first signal than responsive to a signal causing said current, and said second impedance is or is made to be substantially greater responsive to said first signal than responsive to said signal causing said current.

60. An occupant sensor for sensing an occupant in a seat as recited in

claim 59

, wherein at least one of said first and second impedances is provided by at least one of respective first and second inductors.

61. An occupant sensor for sensing an occupant in a seat as recited in

claim 59

, wherein at least one of said first and second impedances is provided by at least one of respective first and second electronic switches.

62. An occupant sensor for sensing an occupant in a seat as recited in

claim 61

, wherein said second signal is operatively coupled to at least one location selected from a control input of said first electronic switch and a control input of said second electronic switch.

78. An occupant sensor for sensing an occupant in a seat as recited in

claim 59

, further comprising at least one first capacitor by which said first signal is operatively coupled.

82. An occupant sensor for sensing an occupant in a seat as recited in

claim 59

, further comprising at least one second capacitor by which said second signal is operatively coupled.

86. An occupant sensor for sensing an occupant in a seat as recited in

claim 59

, further comprising a means for sensing the occupant from a response to said first signal.

90. An occupant sensor for sensing an occupant in a seat as recited in

claim 59

, further comprising a means for controlling the actuation of a safety restraint system responsive to said first signal.

63. An occupant sensor for sensing an occupant in a seat, wherein said seat incorporates a conductive heating element, said occupant sensor comprising:

a) a first electrode located between said heating element and a seating region of said seat;

b) a second electrode located between said heating element and said first electrode;

c) a first signal operatively coupled to said first electrode; and

d) a second signal operatively coupled to said second electrode, wherein said first signal is an oscillating or pulsed signal, and said second signal is substantially equal to said first signal.

64. An occupant sensor for sensing an occupant in a seat as recited in

claim 63

, further comprising:

e) an electrode located on a side of said heating element away from a seating region of said seat; and

f) a second signal operatively coupled to said electrode, wherein said second signal is substantially equal to said first signal.

65. An occupant sensor for sensing an occupant in a seat as recited in

claim 63

, wherein said second electrode comprises a sheath at least partially around at least a portion of said heating element.

79. An occupant sensor for sensing an occupant in a seat as recited in

claim 63

, further comprising at least one first capacitor by which said first signal is operatively coupled.

83. An occupant sensor for sensing an occupant in a seat as recited in

claim 63

, further comprising at least one second capacitor by which said second signal is operatively coupled.

87. An occupant sensor for sensing an occupant in a seat as recited in

claim 63

, further comprising a means for sensing the occupant from a response to said first signal.

91. An occupant sensor for sensing an occupant in a seat as recited in

claim 63

, further comprising a means for controlling the actuation of a safety restraint system responsive to said first signal.

66. An occupant sensor for sensing an occupant in a seat, wherein said seat incorporates a conductive heating element, said occupant sensor comprising:

a) a first impedance operatively connecting a first node of said heating element to a source of power;

b) a second impedance operatively connecting a second node of said heating element to a sink of said power, wherein when a current is caused to flow between said first and second nodes by said source of power, said heating element generates heat; and

c) a first signal operatively coupled to said heating element at a location at or between said first and second nodes, wherein said first signal is an oscillating or pulsed signal, said first impedance is or is made to be substantially greater responsive to said first signal than responsive to a signal causing said current, said second impedance is or is made to be substantially greater responsive to said first signal than responsive to said signal causing said current, said heating element is arranged so as to at least partially bound a region on a vehicle seat located proximate to a portion of an occupant selected from an infant or child that is closest to said seat when the infant or child is seated in an infant seat, a child seat, or a booster seat, and the infant seat, the child seat or the booster seat is placed on said vehicle seat, and said region is devoid of said heating element.

67. An occupant sensor for sensing an occupant in a seat, wherein said seat incorporates a conductive heating element, said occupant sensor comprising:

a) a first impedance operatively connecting a first node of said heating element to a source of power;

b) a second impedance operatively connecting a second node of said heating element to a sink of said power, wherein when a current is caused to flow between said first and second nodes by said source of power, said heating element generates heat, and at least one of said first and second impedances is provided by at least one of respective first and second inductors; and

c) a first signal operatively coupled to said heating element at a location at or between said first and second nodes, wherein said first signal is an oscillating or pulsed signal, said first impedance is or is made to be substantially greater responsive to said first signal than responsive to a signal causing said current, and said second impedance is or is made to be substantially greater responsive to said first signal than responsive to said signal causing said current.

68. An occupant sensor for sensing an occupant in a seat as recited in

claim 67

, further comprising:

a) an electrode located on a side of said heating element away from a seating region of said seat; and

b) a second signal operatively coupled to said electrode, wherein said second signal is substantially equal to said first signal.

80. An occupant sensor for sensing an occupant in a seat as recited in

claim 67

, further comprising at least one first capacitor by which said first signal is operatively coupled.

84. An occupant sensor for sensing an occupant in a seat as recited in

claim 67

, further comprising at least one second capacitor by which said second signal is operatively coupled.

88. An occupant sensor for sensing an occupant in a seat as recited in

claim 67

, further comprising a means for sensing the occupant from a response to said first signal.

92. An occupant sensor for sensing an occupant in a seat as recited in

claim 67

, further comprising a means for controlling the actuation of a safety restraint system responsive to said first signal.

69. An occupant sensor for sensing an occupant in a seat, wherein said seat incorporates a conductive heating element, said occupant sensor comprising:

a) a first impedance operatively connecting a first node of said heating element and a source of power;

b) a second impedance operatively connecting a second node of said heating element and a sink of said power;

c) a third impedance operatively connecting said first impedance and said source of power;

d) a fourth impedance operatively connecting said second impedance and said sink of power, wherein when a current is caused to flow between said first and second nodes by said source of power, said heating element generates heat;

e) a first signal operatively coupled to said heating element at a location at or between said first and second nodes;

f) a second signal operatively coupled to at least one location selected from a third node between said first and third impedances and a fourth node between said second and fourth impedances, wherein said first signal is an oscillating or pulsed signal, said second signal is substantially equal to said first signal, said first impedance is or is made to be substantially greater responsive to said first signal than responsive to a signal causing said current, said second impedance is or is made to be substantially greater responsive to said first signal than responsive to said signal causing said current, said third impedance is or is made to be substantially greater responsive to said first signal than responsive to a signal causing said current, and said fourth impedance is or is made to be substantially greater responsive to said first signal than responsive to said signal causing said current.

70. An occupant sensor for sensing an occupant in a seat as recited in

claim 69

, wherein said heating element is arranged so as to at least partially bound a region on a vehicle seat located proximate to a portion of an occupant selected from an infant or child that is closest to said seat when the infant or child is seated in an infant seat, a child seat, or a booster seat, and the infant seat, the child seat or the booster seat is placed on said vehicle seat, and said region is devoid of said heating element.

71. An occupant sensor for sensing an occupant in a seat as recited in

claim 70

, wherein at least one of said first and second impedances is provided by at least one of respective first and second inductors.

72. An occupant sensor for sensing an occupant in a seat as recited in

claim 71

, wherein at least one of said third and fourth impedances is provided by at least one of respective third and fourth inductors.

73. An occupant sensor for sensing an occupant in a seat as recited in

claim 71

, wherein at least one of said third and fourth impedances is provided by at least one of respective third and fourth electronic switches.

74. An occupant sensor for sensing an occupant in a seat as recited in

claim 70

, wherein at least one of said first and second impedances is provided by at least one of respective first and second electronic switches.

75. An occupant sensor for sensing an occupant in a seat as recited in

claim 74

, wherein said second signal is operatively coupled to at least one location selected from a control input of said first electronic switch and a control input of said second electronic switch.

76. An occupant sensor for sensing an occupant in a seat as recited in

claim 74

, wherein at least one of said third and fourth impedances is provided by at least one of respective third and fourth inductors.

77. An occupant sensor for sensing an occupant in a seat as recited in

claim 74

, wherein at least one of said third and fourth impedances is provided by at least one of respective third and fourth electronic switches.

81. An occupant sensor for sensing an occupant in a seat as recited in

claim 69

, further comprising at least one first capacitor by which said first signal is operatively coupled.

85. An occupant sensor for sensing an occupant in a seat as recited in

claim 69

, further comprising at least one second capacitor by which said second signal is operatively coupled.

89. An occupant sensor for sensing an occupant in a seat as recited in

claim 69

, further comprising a means for sensing the occupant from a response to said first signal.

93. An occupant sensor for sensing an occupant in a seat as recited in

claim 69

, further comprising a means for controlling the actuation of a safety restraint system responsive to said first signal.