Activation control apparatus for passive vehicle occupant restraint and method of controlling activation of passive vehicle occupant restraint

• US 6,170,864 B1
• Filed: 10/31/1997
• Issued: 01/09/2001
• Est. Priority Date: 11/20/1996
• Status: Expired due to Term

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Iyoda, Motomi, Sugiyama, Koichi, Fujita, Koichi, Fujishima, Hiromichi, Sakaguchi, Tomokazu, Akatsuka, Takao
• Primary Examiner(s): Dickson, Paul N.
• Assistant Examiner(s): Dunn, David R.
• Application Number:
  US08/962,386
• Time in Patent Office: 1,166 Days
• Field of Search: 280/735, 280/734, 180/282, 701/45-47, 340/436, 307/10.1
• US Class Current: 280/735
• CPC Class Codes: B60R 2021/01006 Mounting of electrical components in vehicles
• CPC Class Codes: B60R 2021/0104 Communication circuits for data transmission
• CPC Class Codes: B60R 2021/01068 between different sensors and airbag control unit
• CPC Class Codes: B60R 2021/01075 between the airbag control unit and pyrotechnic fuses or equivalent actuators
• CPC Class Codes: B60R 2021/01322 comprising variable thresholds, e.g. depending from other collision parameters
• CPC Class Codes: B60R 21/013 including means for detecting collisions, impending collisions or roll-over
• CPC Class Codes: B60R 21/0133 by integrating the amplitude of the input signal
• CPC Class Codes: B60R 21/01558 monitoring crash strength

Abstract

A floor sensor 32 measures a deceleration G applied to the length of a vehicle and outputs the deceleration as the measurement G. An arithmetic unit 58 carries out a predetermined arithmetic operation on the measurement G output from the floor sensor 32, so as to determine a function f(G). A conditional activation unit 60 has a variation pattern of a threshold value T that varies with a variation in velocity v of a non-stationary object. The conditional activation unit 60 reads a threshold value T corresponding to an input velocity v from the variation pattern and compares the threshold value T with the value of the function f(G). In case that the value of the function f(G) exceeds the threshold value T, an activation signal A is input to a driving circuit 34. A satellite sensor 30 outputs an ON signal when a deceleration of not less than a predetermined reference value is applied to the vehicle. A threshold variation pattern changing unit 42 changes the variation pattern of the threshold value T against the velocity v used in the conditional activation unit 60 to another variation pattern, in response to the ON signal output from the satellite sensor 30. This structure of the present invention enables a passive vehicle occupant restraint to be activated at the earliest possible timing, irrespective of a type of a collision, in which the vehicle crashes.

Claims

1. An activation control apparatus for controlling activation of a passive vehicle occupant restraint mounted on a vehicle, said activation control apparatus comprising:

an impact measurement sensor disposed at a predetermined position in said vehicle which measures an impact applied to said vehicle;

an activation controller which compares a value calculated from the measurement of the impact by said impact measurement sensor with a threshold value that varies according to a specified threshold variation pattern, and controls activation of said passive vehicle occupant restraint based on the result of comparison;

an impact detector disposed at a position ahead of said impact measurement sensor in said vehicle which determines whether or not the impact applied to said vehicle is not less than a specified reference value; and

a threshold variation pattern changer which changes said specified threshold variation pattern to another threshold variation pattern when said impact detector determines that the impact applied to said vehicle is not less than said specified reference value.

2. An activation control apparatus in accordance with claim 1, wherein said impact detector comprises a plurality of detectors, each said detector having a different value as said specified reference value and determining whether or not the impact applied to said vehicle is not less than its reference value,

said threshold variation pattern changer selecting one reference value that satisfies a specified condition among a plurality of said reference values, and changing said specified threshold variation pattern to another threshold variation pattern when at least one of said detectors determines that the impact applied to said vehicle is not less than said selected reference value.

3. An activation control apparatus in accordance with claim 1, wherein said specified reference value is set to be greater than a value of impact detected at the position of said impact detector in the case of a specific type of collision that applies an impact to said vehicle of such a degree that activation of said passive vehicle occupant restraint is not required.

4. An activation control apparatus in accordance with claim 1, wherein the result of detection by said impact detector is transmitted from said impact detector to said activation threshold variation pattern changer via a transmission path which is partly divided into a plurality of paths.

5. An activation control apparatus in accordance with claim 1, wherein a plurality of said impact detectors are disposed at a plurality of different positions.

6. An activation control apparatus in accordance with claim 1, wherein a plurality of said impact detectors are disposed off to a right front and a left front of said impact measurement sensor in said vehicle, the result of detection by said each impact detector is transmitted from said each impact detector to said threshold variation pattern changer via a transmission path which is partly divided into left and right transmission paths, said left and right transmission paths respectively going through a left side and a right side in said vehicle.

7. An activation control apparatus in accordance with claim 1, wherein said threshold variation pattern represents a variation of said threshold value against a velocity of a non-stationary object in said vehicle.

28. An activation control apparatus in accordance with claim 1, wherein

said impact measurement sensor measures deceleration as an impact applied to said vehicle, and

said activation controller uses a value obtained by integrating said measured deceleration once with respect to time as said value calculated from the measurement of the impact by said impact measurement sensor.

29. An activation control apparatus in accordance with claim 1, wherein said specified reference value is set to be greater than a value of an impact detected at the position of said impact detector, in the case of a head-on collision that applies an impact to said vehicle of such a degree that activation of said passive vehicle occupant restraint is not required.

30. An activation control apparatus in accordance with claim 1, wherein said specified reference value is set to be greater than a value of an impact to said vehicle detected at the position of said impact detector while said vehicle is driving on a rough road.

31. An activation control apparatus in accordance with claim 1, wherein

said threshold variation pattern used before said impact detector determines that the impact applied to said vehicle is not less than said specified reference value comprises a specific line whose value is greater than those of one or more first curves and/or one or more second curves,

said one or more first curves representing the variation of a value with respect to a predetermined physical value based on said value measured by said impact measurement sensor in the case of a head-on collision that applies an impact of such a degree that activation of said passive vehicle occupant restraint is not required, and

said one or more second curves representing the variation of a value with said predetermined physical value based on said value measured by said impact measurement sensor while said vehicle is driving on a rough road.

32. An activation control apparatus in accordance with claim 31, wherein said specific line envelopes said one or more first curves and/or said one or more second curves.

33. An activation control apparatus in accordance with claim 31, wherein said predetermined physical value represents the speed of an object assumed not to be fixed in said vehicle.

34. An activation control apparatus in accordance with claim 31, wherein said predetermined physical value represents time.

35. An activation control apparatus in accordance with claim 1, wherein said threshold variation pattern used after said impact detection means determines that the impact applied to said vehicle is not less than said specified reference value comprises a specified line whose value is greater than that of one or more curves representing the variation of a value with a predetermined physical value based on said value that would be measured by said impact measurement sensor in the case of a specific type of a collision other than a head-on collision that applies an impact to said vehicle of such a degree that activation of said passive vehicle occupant restraint is not required.

36. An activation control apparatus in accordance with claim 35, wherein said specific line envelopes said one or more curves.

37. An activation control apparatus in accordance with claim 35, wherein said predetermined physical value represents the speed of an object assumed not to be fixed in said vehicle.

38. An activation control apparatus in accordance with claim 35, wherein said predetermined physical value represents time.

39. An activation control apparatus in accordance with claim 1, wherein said impact detector comprises:

a signal output terminal for outputting detection results;

a diode whose one end is connected with said signal output terminal;

a first resistor whose one end is connected with the other end of said diode;

an integral switch whose one end is connected with said other end of said diode, and which is arranged in parallel with said first resistor and is turned on in the case of an impact of not less than said specified reference value; and

a second resistor whose one end is connected with the other end of said first resistor and the other end of said internal switch, and the other end of said second resistor is connected with an earth.

40. An activation control apparatus in accordance with claim 39, wherein said impact detector means comprises:

two or more of said signal output terminals and said diodes respectively, wherein

each of said signal output terminals is connected with one end of each of said diodes, and

a transmission path which transmits the detection results detected by said impact detector from said impact detector to said threshold variation pattern changer comprises two or more signal lines that are connected with said signal output terminals respectively.

41. An activation control apparatus in accordance with claim 39, wherein said impact detector comprises:

two or more of said signal output terminals and said diodes respectively, each of said signal output terminals being connected with one end of each of said diodes; and

one or more earth output terminals, wherein

a transmission path which transmits the detection results detected by said impact detector from said impact detector to said threshold variation pattern changer comprises two or more signal lines that are connected with said signal output terminals respectively, and one or more earth lines that are connected with said one or more earth output terminals.

8. An activation control apparatus for controlling activation of a passive vehicle occupant restraint mounted on a vehicle, said activation control apparatus comprising:

an impact measurement sensor disposed at a predetermined position in said vehicle which measures an impact applied to said vehicle;

an activation controller which compares a value calculated from the measurement of the impact by said impact measurement sensor with a specified threshold value, and controls activation of said passive vehicle occupant restraint based on the result of comparison;

an impact detector disposed at a position ahead of said impact measurement sensor in said vehicle which determines whether or not the impact applied to said vehicle is not less than a specified reference value; and

a threshold value changer which changes said specified threshold value to another threshold value when said impact detector determines that the impact applied to said vehicle is not less than said specified reference value.

9. An activation control apparatus in accordance with claim 8, wherein said impact detector comprises a plurality of detectors, each said detector having a different value as said specified reference value and determining whether or not the impact applied to said vehicle is not less than its reference value,

said threshold value changer selecting one reference value that satisfies a specified condition among a plurality of said reference values, and changing said specified threshold value to another threshold value when at least one of said detectors determines that the impact applied to said vehicle is not less than said selected reference value.

10. An activation control apparatus in accordance with claim 8, wherein said specified reference value is set to be greater than a value of impact detected at the position of said impact detector in the case of a specific type of collision that applies an impact to said vehicle of such a degree that activation of said passive vehicle occupant restraint is not required.

11. An activation control apparatus in accordance with claim 8, wherein the result of detection by said impact detector is transmitted from said impact detector to said threshold value changer via a transmission path which is partly divided into a plurality of paths.

12. An activation control apparatus in accordance with claim 8, wherein a plurality of said impact detectors are disposed at a plurality of different positions.

13. An activation control apparatus in accordance with claim 8, wherein a plurality of said impact detectors are disposed off to a right front and a left front of said impact measurement sensor in said vehicle, the result of detection by said each impact detector is transmitted from said each impact detector to said threshold value changer via a transmission path which is partly divided into left and right transmission paths, said left a nd right transmission paths respectively going through a left side and a right side in said vehicle.

42. An activation control apparatus in accordance with claim 8, wherein

said impact measurement sensor measures deceleration as an impact applied to said vehicle,

said activation controller uses a value obtained by integrating said measured deceleration once with respect to time, as a value obtainable based on the measurement by said impact measurement means.

43. An activation control apparatus in accordance with claim 8, wherein said specified reference value is set to be greater than a value of an impact that would be detected at the position of said impact detector, in the case of a head-on collision that applies an impact to said vehicle of such a degree that activation of said passive vehicle occupant restraint is not required.

44. An activation control apparatus in accordance with claim 8, wherein said specified reference value is set to be greater than a value of an impact to said vehicle detected at the position of said impact detector while said vehicle is driving on a rough road.

45. An activation control apparatus in accordance with claim 8, wherein said threshold value used before said impact detector determines that the impact applied to said vehicle is not less than said specified reference value is greater than a first value and/or a second value,

said first value being based on said value measured by said impact measurement sensor at a certain point of time in the case of a head-on collision that applies an impact to said vehicle of such a degree that activation of said passive vehicle occupant restraint is not required, and

said second value being based on said value measured by said impact measurement sensor at a certain point of time said vehicle is driving on a rough road.

46. An activation control apparatus in accordance with claim 45, wherein said threshold value is greater than said first value and/or said second value by a certain value.

47. An activation control apparatus in accordance with claim 8, wherein

said threshold value used after said impact detector determines that the impact applied to said vehicle is not less than said specified reference value is greater than a specific value, said specific value being based on said value measured by said impact measurement sensor at a certain point of time in the case of a specific type of a collision other than a head-on collision that applies an impact of such a degree that activation of said passive vehicle occupant restraint is not required.

48. An activation control apparatus in accordance with claim 47, wherein said threshold value is greater than said specific value by a certain value.

49. An activation control apparatus in accordance with claim 8, wherein

said impact detector comprises:

a signal output terminal for outputting detection results;

a diode whose one end is connected with said signal output terminal;

a first resistor whose one end is connected with the other end of said diode;

an internal switch whose one end is connected with said other end of said diode, and which is arranged in parallel with said first resistor and is turned on in the case of an impact applied to said vehicle of not less than said specified reference value; and

a second resistor whose one end is connected with the other end of said first resistor and said internal switch, and the other end is connected with an earth.

50. An activation control apparatus in accordance with claim 49, wherein said impact detector comprises:

two or more of said signal output terminals and said diodes respectively, wherein

each of said signal output terminals is connected with one end of each of said diodes, and

a transmission path which transmits the detection results detected by said impact detector from said impact detector to said threshold value changer comprises two or more signal lines that are connected with said signal output terminals respectively.

51. An activation control apparatus in accordance with claim 49, wherein said impact detector comprises:

two or more of said signal output terminals and said diodes respectively, each of said signal output terminals being connected with one end of each of said diodes; and

one or more earth output terminals, wherein

a transmission path which transmits the detection results detected by said impact detector from said impact detector to said threshold value changer comprises two or more signal lines that are connected with said signal output terminals respectively, and one or more earth lines that are connected with said one or more earth output terminals, respectively.

14. An activation control apparatus for controlling activation of a passive vehicle occupant restraint mounted on a vehicle, said activation control apparatus comprising:

an impact measurement sensor disposed at a predetermined position in said vehicle which measures an impact applied to said vehicle;

an activation controller which compares a value calculated from the measurement of the impact by said impact measurement sensor with a threshold value that varies according to a specified threshold variation pattern, and controls activation of said passive vehicle occupant restraint based on the result of comparison;

an impact direction detector for specifying a direct ion of the impact applied to said vehicle; and

a threshold variation pattern changer which changes said specified threshold variation pattern to another threshold variation pattern when the direction of the impact specified by said impact direction detector coincides with a preset direction.

15. An activation control apparatus in accordance with claim 14, wherein said impact direction detector specifies the direction of the impact, based on a measurement of the impact applied to a length of said vehicle and a measurement of the impact applied to a width of said vehicle by said impact measurement sensor.

16. An activation control apparatus in accordance with claim 14, wherein said threshold variation pattern represents a variation of said threshold value against a velocity of a non-stationary object in said vehicle.

17. An activation control apparatus for controlling activation of a passive vehicle occupant restraint mounted on a vehicle, said activation control apparatus comprising:

an impact measurement sensor disposed at a predetermined position in said vehicle which measures an impact applied to said vehicle;

an activation controller which compares comparing a value calculated from the measurement of the impact by said impact measurement sensor with a specified threshold value, and controls activation of said passive vehicle occupant restraint based on the result of comparison;

an impact direction detector which specifies a direction of the impact applied to said vehicle; and

a threshold value changer which changes said specified threshold value to another threshold value when the direction of the impact specified by said impact direction detection means coincides with a preset direction.

18. An activation control apparatus in accordance with claim 17, wherein said impact direction detector specifies the direction of the impact, based on a measurement of the impact applied to a length of said vehicle and a measurement of the impact applied to a width of said vehicle by said impact measurement sensor.

19. An activation control apparatus for controlling activation of a passive vehicle occupant restraint mounted on a vehicle, said activation control apparatus comprising:

an impact measurement sensor disposed at a predetermined position in said vehicle which measures an impact applied to said vehicle;

an activation controller which compares a value calculated from the measurement of the impact by said impact measurement sensor with a threshold value that varies according to a specified threshold variation pattern, and controls activation of said passive vehicle occupant restraint based on the result of comparison;

a collision type specifying sensor which specifies a type of a collision in which said vehicle crashes;

a seating state detector which detects a seating state of a vehicle occupant in said vehicle; and

a threshold variation pattern changer which changes said specified threshold variation pattern to another threshold variation pattern when the type of the collision specified by said collision type specifying sensor coincides with a specified type of a collision and when the seating state detected by said seating state detector coincides with a specified seating state.

20. An activation control apparatus in accordance with claim 19, wherein said threshold variation pattern represents a variation of said threshold value against a velocity of a non-stationary object in said vehicle.

21. An activation control apparatus for controlling activation of a passive vehicle occupant restraint mounted on a vehicle, said activation control apparatus comprising:

an impact measurement sensor disposed at a predetermined position in said vehicle which measures an impact applied to said vehicle;

an activation controller which compares a value calculated from the measurement of the impact by said impact measurement sensor with a specified threshold value, and controlling activation of said passive vehicle occupant restraint based on the result of comparison;

a collision type specifying sensor which specifies a type of a collision in which said vehicle crashes;

a seating state detector which detects a seating state of a vehicle occupant in said vehicle; and

a threshold value changer which changes said specified threshold value to another threshold value when the type of the collision specified by said collision type specifying sensor coincides with a specified type of a collision and when the seating state detected by said seating state detector coincides with a specified seating state.

22. A method of controlling activation of a passive vehicle occupant restraint mounted on a vehicle, said method comprising the steps of:

(a) measuring a value of impact at a first position in said vehicle when an impact is applied to said vehicle;

(b) comparing a value calculated from the measurement of the impact in said step (a) with a threshold value that varies according to a specified threshold variation pattern, and controlling activation of said passive vehicle occupant restraint based on the result of comparison;

(c) determining whether or not a value of impact detected at a second position, which is ahead of said first position in said vehicle, is not less than a specified reference value when the impact is applied to said vehicle; and

(d) when the value of impact detected at said second position is determined to be not less than said specified reference value in said step (c), changing said threshold variation pattern to another threshold variation pattern.

23. A method of controlling activation of a passive vehicle occupant restraint mounted on a vehicle, said method comprising the steps of:

(a) measuring a value of impact at a first position in said vehicle when an impact is applied to said vehicle;

(b) comparing a value calculated from the measurement of the impact in said step (a) with a specified threshold value, and controlling activation of said passive vehicle occupant restraint based on the result of comparison;

(c) determining whether or not a value of impact detected at a second position, which is ahead of said first position in said vehicle, is not less than a specified reference value when the impact is applied to said vehicle; and

(d) when the value of impact detected at said second position is determined to be not less than said specified reference value in said step (c), changing said threshold value to another threshold value.

24. A method of controlling activation of a passive vehicle occupant restraint mounted on a vehicle, said method comprising the steps of:

(a) measuring a value of impact at a predetermined position in said vehicle when an impact is applied to said vehicle;

(b) comparing a value calculated from the measurement of the impact in said step (a) with a threshold value that varies according to a specified threshold variation pattern, and controlling activation of said passive vehicle occupant restraint based on the result of comparison;

(c) specifying a direction of the impact applied to said vehicle; and

(d) when the direction of the impact specified in said step (c) coincides with a preset direction, changing said specified threshold variation pattern to another threshold variation pattern.

25. A method of controlling activation of a passive vehicle occupant restraint mounted on a vehicle, said method comprising the steps of:

(a) measuring a value of impact at a predetermined position in said vehicle when an impact is applied to said vehicle;

(b) comparing a value calculated from the measurement of the impact in said step (a) with a specified threshold value, and controlling activation of said passive vehicle occupant restraint based on the result of comparison;

(c) specifying a direction of the impact applied to said vehicle; and

(d) when the direction of the impact specified in said step (c) coincides with a preset direction, changing said specified threshold value to another threshold value.

26. A method of controlling activation of a passive vehicle occupant restraint mounted on a vehicle, said method comprising the steps of:

(a) measuring a value of impact at a predetermined position in said vehicle when an impact is applied to said vehicle;

(b) comparing a value calculated from the measurement of the impact in said step (a) with a threshold value that varies according to a specified threshold variation pattern, and controlling activation of said passive vehicle occupant restraint based on the result of comparison;

(c) specifying a type of a collision in which said vehicle crashes;

(d) detecting a seating state of a vehicle occupant in said vehicle; and

(e) when the type of the collision specified in said step (c) coincides with a specified type of a collision and when the seating state detected in said step (d) coincides with a specified seating state, changing said specified threshold variation pattern to another threshold variation pattern.

27. A method of controlling activation of a passive vehicle occupant restraint mounted on a vehicle, said method comprising the steps of:

(a) measuring a value of impact at a predetermined position in said vehicle when an impact is applied to said vehicle;

(b) comparing a value calculated from the measurement of the impact in said step (a) with a specified threshold value, and controlling activation of said passive vehicle occupant restraint based on the result of comparison;

(c) specifying a type of a collision in which said vehicle crashes;

(d) detecting a seating state of a vehicle occupant in said vehicle; and

(e) when the type of the collision specified in said step (c) coincides with a specified type of a collision and when the seating state detected in said step (d) coincides with a specified seating state, changing said specified threshold value to another threshold value.