Starting apparatus of passenger protecting apparatus and method thereof

• US 5,555,174 A
• Filed: 04/07/1995
• Issued: 09/10/1996
• Est. Priority Date: 05/29/1992
• Status: Expired due to Term

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation), Mitsubishi Jidosha Kogyo Kabushiki Kaisha
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation), Mitsubishi Jidosha Kogyo Kabushiki Kaisha
• Inventors: Furui, Takashi, Ohmae, Katsuhiko, Okimoto, Yukihiro
• Primary Examiner(s): Teska, Kevin J.
• Assistant Examiner(s): Walker, Tyrone V.
• Application Number:
  US08/418,480
• Time in Patent Office: 522 Days
• Field of Search: 364/424.05, 340/436, 340/669, 307/10.1, 280/734, 280/735, 180/274, 180/282
• US Class Current: 701/46
• CPC Class Codes: B60R 2021/01122 Prevention of malfunction
• CPC Class Codes: B60R 2021/01322 comprising variable thresholds, e.g. depending from other collision parameters
• CPC Class Codes: B60R 21/0132 responsive to vehicle motion parameters , e.g. to vehicle longitudinal or transversal deceleration or speed value
• CPC Class Codes: B60R 21/0133 by integrating the amplitude of the input signal

Abstract

A starting apparatus of a passenger protecting apparatus is actuated by detecting collision of a vehicle. The starting apparatus is provided so as to subtract a predetermined value from an acceleration signal fed from G sensor and integrate the subtracted acceleration signal, and forcedly set an integrated value to zero if the integrated value is less than zero. Further, the starting apparatus is provided so as to provide a starting signal when the integrated value exceeds a preset threshold value. Therefore, it is possible to discriminate collision to start the apparatus from other collision, prevent starting means from being unnecessarily actuated, and avoid malfunction of the starting means.

Claims

1. A starting apparatus of a passenger protecting apparatus comprising:

an acceleration sensor converting an acceleration at a time of collision into an acceleration signal;

subtracting means for subtracting a predetermined offset value from said acceleration signal output from said acceleration sensor;

speed calculating means for integrating output from said subtracting means so as to obtain a speed signal;

limiting means for limiting said speed signal to zero when an integrated value of said output from said subtracting means becomes smaller than zero;

comparing means for comparing an output from said speed calculating means with a threshold value; and

starting means for outputting a starting signal depending upon an output from said comparing means.

7. A starting apparatus of a passenger protecting apparatus according to claim 1, further comprising:

holding means for maintaining said starting signal for a predetermined length of time.

8. A starting apparatus of a passenger protecting apparatus according to claim 1, wherein,

said predetermined offset value is set at a value where the output of said subtracting means is a negative value when a vehicle is running at a low speed and starting of said passenger protecting apparatus is not necessary.

2. A starting apparatus of a passenger protecting apparatus comprising:

an acceleration sensor converting an acceleration at a time of collision into an acceleration signal;

a low speed determining portion having,

first subtracting means for subtracting a first predetermined offset value from said acceleration signal output from said acceleration sensor,

first speed calculating means for integrating an output from said first subtracting means so as to obtain a first speed signal, and

first comparing means for comparing an output from said first speed calculating means with a first threshold value, and

first limiting means for limiting said first speed signal to zero when an integrated value of said output from said first subtracting means becomes smaller than zero;

a high speed determining portion having,

second subtracting means for subtracting a second predetermined offset value from said acceleration signal output from said acceleration sensor,

second speed calculating means for integrating an output from said second subtracting means so as to obtain a second speed signal, and

second comparing means for comparing an output from said second speed calculating means with a second threshold value larger than said first threshold value, and

second limiting means for limiting said second speed signal to zero when an integrated value of said output from said second subtracting means becomes smaller than zero;

an AND circuit obtaining an AND of an output from said low speed determining portion and an output from said high speed determining portion; and

starting means for outputting a starting signal depending upon an output from said AND circuit.

3. A starting apparatus of a passenger protecting apparatus according to claim 2, wherein said first predetermined offset value is smaller than said predetermined offset value.

4. A starting apparatus of a passenger protecting apparatus according to claim 2, wherein said first threshold value is smaller than said second threshold value.

5. A starting apparatus of a passenger protecting apparatus comprising:

an acceleration sensor converting an acceleration at a time of collision into an acceleration signal;

a filter allowing only particular frequencies in acceleration signals output from said acceleration sensor to pass;

subtracting means for subtracting a predetermined offset value from an output from said filter;

speed calculating means for integrating an output from said subtracting means so as to obtain a speed signal;

limiting means for limiting said speed signal to zero when an integrated value of said output from said subtracting means becomes smaller than zero;

comparing means for comparing an output from said speed calculating means with a threshold value; and

starting means for outputting a starting signal depending upon an output from said comparing means.

6. A starting apparatus of a passenger protecting apparatus according to claim 5, wherein:

said filter cuts frequencies peculiar to a collision against a rear end of a truck.

22. A starting apparatus of a passenger protecting apparatus according to claim 5, wherein:

said predetermined offset value is set at a value where said output of said subtracting means is a negative value when a vehicle is running at a low speed and starting of said passenger protecting apparatus is not necessary.

9. A starting apparatus of a passenger protecting apparatus, comprising:

an acceleration sensor converting an acceleration at a time of collision into an acceleration signal;

a subtractor subtracting a predetermined offset value from the acceleration signal output from said acceleration sensor;

an integrator integrating output from said subtractor to obtain a speed signal;

a limiter limiting said speed signal to zero when an integrated value of said output from said subtractor becomes smaller than zero;

a comparator comparing an output from either one of said integrator or said limiter with a threshold value; and

a starter outputting a starting signal based on an output from said comparator.

10. A starting apparatus of a passenger protecting apparatus according to claim 9, further comprising:

a timer maintaining said starting signal for a predetermined length of time.

11. A starting apparatus of a passenger protecting apparatus according to claim 9, wherein,

said predetermined offset value is set at a value where said output of said subtractor is a negative value when a vehicle is running at a low speed and starting of said passenger protecting apparatus is not necessary.

12. A method for starting a passenger protecting apparatus, comprising the steps of:

(a) detecting an amount of acceleration applied to a vehicle;

(b) subtracting a predetermined offset value from said amount of acceleration detected in said step (a) to obtain a subtracted value;

(c) integrating said subtracted value calculated in said step (b) to obtain a speed signal;

(d) limiting said speed signal to zero when an integrated value of said subtracted value becomes smaller than zero;

(e) comparing said speed signal with a threshold value; and

(f) generating a starting signal for starting said passenger protecting apparatus according to the comparison result in said step (e).

13. The method for starting a passenger protecting apparatus according to claim 12, further comprising the step of:

(g) maintaining said start signal for a predetermined period of time.

14. The method for starting a passenger protecting apparatus according to claim 12, wherein,

said predetermined offset value is set at a value such that said subtracted value is a negative value when a vehicle is running at a low speed and starting of said passenger protecting apparatus is not necessary.

15. A starting apparatus of a passenger protecting apparatus comprising:

an acceleration sensor converting an acceleration at a time of collision into an acceleration signal;

a first subtractor subtracting a first predetermined offset value from said acceleration signal output from said acceleration sensor;

a first integrator integrating output from said first subtractor to obtain a first speed signal;

a first limiter limiting said first speed signal to zero when an integrated value of said output from said first subtractor becomes smaller than zero;

a first comparator comparing an output from either one of said first integrator or said first limiter with a first threshold value;

a first starter outputting a first starting signal based on an output from said first comparator;

a second subtractor subtracting a second predetermined offset value from said acceleration signal output from said acceleration sensor;

a second integrator integrating output from said second subtractor to obtain a second speed signal;

a second limiter limiting said second speed signal to zero when an integrated value of said output from said second subtractor becomes smaller than zero;

a second comparator comparing an output from either one of said second integrator or said second limiter with a second threshold value;

a second starter outputting a second signal based on an output from said second comparator; and

a third starter outputting a third starting signal to start said passenger protecting apparatus when said first starting signal and said second starting signal are both outputted.

16. A starting apparatus of a passenger protecting apparatus according to claim 15, wherein:

said third starting signal is outputted when both said first starting signal and said second starting signal are outputted within a predetermined period of time.

17. A starting apparatus of a passenger protecting apparatus according to claim 15, wherein:

said first starting signal is indicative of a low speed collision, and said second starting signal is indicative of a high speed collision.

18. A starting apparatus of a passenger protecting apparatus according to claim 15, wherein said third starter comprises:

an AND circuit for receiving said first starting signal and said second starting signal and outputting said third starting signal.

19. A method for starting a passenger protecting apparatus, comprising the steps of:

(a) detecting an amount of acceleration applied to a vehicle;

(b) subtracting a first predetermined offset value from said amount of acceleration detected in said step (a) to obtain a first subtracted value;

(c) integrating said first subtracted value calculated in said step (b) to obtain a first speed signal;

(d) limiting said first speed signal to zero when an integrated value of said first subtracted value becomes smaller than zero;

(e) comparing said first speed signal with a first threshold value; and

(f) generating a first starting signal according to the comparison result in said step (e);

(g) subtracting a second predetermined offset value from said amount of acceleration detected in said step (a) to obtain a second subtracted value;

(h) integrating said second subtracted value calculated in said step (g) to obtain a second speed signal;

(i) limiting said second speed signal to zero when an integrated value of said second subtracted value becomes smaller than zero;

(j) comparing said second speed signal with a second threshold value; and

(k) generating a second starting signal according to the comparison result in said step (j);

(l) generating a third starting signal for starting said passenger protecting apparatus when both said first starting signal and said second starting signal are generated.

20. The method for starting a passenger protecting apparatus according to claim 19, wherein:

said third starting signal is generated when both said first starting signal and said second starting signal are generated within a predetermined period of time.

21. The method for starting a passenger protecting apparatus according to claim 19, wherein:

said first starting signal is indicative of a low speed collision, and said second starting signal is indicative of a high speed collision.

23. A starting apparatus of a passenger protecting apparatus, comprising:

an acceleration sensor converting an acceleration at a time of collision into an acceleration signal;

a filter allowing only particular frequencies in said acceleration signals output from said acceleration sensor;

a subtractor subtracting a predetermined offset value from said acceleration signal output from said acceleration sensor;

an integrator integrating output from said subtractor to obtain a speed signal;

a limiter limiting said speed signal to zero when an integrated value of said output subtractor becomes smaller than zero;

a comparator comparing an output from either one of said integrator or said limiter with a threshold value; and

a starter outputting a starting signal based on an output from said comparator.

24. A starting apparatus of a passenger protecting apparatus according to claim 23, wherein:

said predetermined offset value is set at a value where an output of said subtractor is a negative value when a vehicle is running at a low speed and starting of said passenger protecting apparatus is not necessary.

25. A starting apparatus of a passenger protecting apparatus according to claim 23, wherein:

said filter cuts frequencies peculiar to a collision against a rear end of a truck.

26. A method for starting a passenger protecting apparatus, comprising the steps of:

(a) detecting an amount of acceleration applied to a vehicle;

(b) filtering said amount of acceleration detected by said step (a) to pass only particular frequencies;

(c) subtracting a predetermined offset value from said amount of acceleration detected in said step (a) and filtered in said step (b) to obtain a subtracted value;

(d) integrating said subtracted value calculated in said step (c) to obtain a speed signal;

(e) limiting said speed signal to zero when an integrated value of said subtracted value becomes smaller than zero;

(f) comparing said speed signal with a threshold value; and

(g) generating a starting signal for starting said passenger protecting apparatus according to the comparison result in said step (f).

27. The method for starting a passenger protecting apparatus according to claim 26, wherein,

said predetermined offset value is set at a value such that said subtracted value is a negative value when a vehicle is running at a low speed and starting of said passenger protecting apparatus is not necessary.

28. The method for starting a passenger protecting apparatus according to claim 26, wherein,

frequencies peculiar to a collision against a rear end of a truck are cut in said step (b).