Occupant restraint apparatus and method of controlling occupant restraint apparatus

• US 6,213,510 B1
• Filed: 11/22/1999
• Issued: 04/10/2001
• Est. Priority Date: 11/27/1998
• Status: Expired due to Fees

• Current Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Original Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Inventors: Suyama, Kouichi
• Primary Examiner(s): ENGLISH, PETER C
• Application Number:
  US09/444,452
• Time in Patent Office: 505 Days
• Field of Search: 280/805, 280/806, 180/268, 701/45
• US Class Current: 280/805
• CPC Class Codes: B60R 2022/288 with means to adjust or regulate the amount of energy to be absorbed
• CPC Class Codes: B60R 21/01512 Passenger detection systems
• CPC Class Codes: B60R 21/01526 using piezoelectric elements
• CPC Class Codes: B60R 21/01542 detecting passenger motion
• CPC Class Codes: B60R 21/01548 sensing the amount of belt winded on retractor
• CPC Class Codes: B60R 21/01558 monitoring crash strength
• CPC Class Codes: B60R 21/16 Inflatable occupant restraints or confinements designed to inflate upon impact or impending impact, e.g. air bags protective garments with automatically inflatable shock-absorbing means A41D13/018; connection of valves to inflatable elastic bodies B60C29/00
• CPC Class Codes: B60R 22/341 comprising energy-absorbing means
• CPC Class Codes: B60R 22/42 having means for acting directly upon the belt, e.g. by clamping or friction not combined with the retractor B60R22/185

Abstract

When an impact energy absorbing mechanism on a vehicle is in operation, a paid-out length of a seat belt is detected by a displacement sensor, and a paid-out speed of the seat belt is calculated by a paid-out speed calculating unit. Based on speed information from a speed sensor, a vehicle speed detecting unit calculates a speed of the vehicle with respect to a ground surface on which the vehicle runs. Then, an occupant acceleration calculating unit calculates an acceleration of an occupant with respect to the ground surface from the calculated paid-out speed and the calculated speed of the vehicle. Impact forces applied to the occupant can be reduced simply and highly accurately irrespectively of the weight of the occupant and whether an air bag is installed in the vehicle or not.

Claims

1. An occupant restraint apparatus for use on a vehicle, comprising:

an impact energy absorbing mechanism for preventing a seat belt from being paid out to restrain an occupant in an emergency and allowing the seat belt to be paid out when a load in excess of a preset load is applied to said seat belt;

length detecting means for detecting a paid-out length of said seat belt when said impact energy absorbing mechanism is operated;

paid-out speed calculating means for calculating a paid-out speed of said seat belt from the paid-out length detected by said length detecting means;

vehicle speed detecting means for detecting a speed of the vehicle with respect to a ground surface on which said vehicle runs; and

occupant acceleration calculating means for calculating an acceleration of said occupant with respect to said ground surface based on the calculated paid-out speed and the detected speed of the vehicle.

2. An occupant restraint apparatus according to claim 1, further comprising:

angle detecting means for detecting a paid-out angle of said seat belt;

said paid-out speed calculating means comprising means for calculating the paid-out speed of said seat belt in view of the paid-out angle of said seat belt detected by said angle detecting means.

3. An occupant restraint apparatus according to claim 1, wherein said impact energy absorbing mechanism comprises:

clamp means for clamping said seat belt in an emergency; and

variable load applying means for varying the load imposed on the paying-out of said seat belt by said clamp means based on the acceleration of said occupant calculated by said occupant acceleration calculating means.

4. An occupant restraint apparatus according to claim 3, wherein said occupant acceleration calculating means comprises means for calculating a differential with respect to time of the acceleration of the occupant with respect to the ground surface.

5. An occupant restraint apparatus according to claim 3, further comprising:

air bag operation detecting means for detecting operation of an air bag in the vehicle;

said variable load applying means comprising means for varying the load imposed on the paying-out of said seat belt by said clamp means based on the acceleration of said occupant calculated by said occupant acceleration calculating means and the operation of the air bag detected by said air bag operation detecting means.

6. An occupant restraint apparatus according to claim 3, further comprising:

occupant position detecting means for detecting the position of the occupant as seated in a longitudinal direction of the vehicle;

said variable load applying means comprising means for varying the load imposed on the paying-out of said seat belt by said impact energy absorbing mechanism based on the acceleration of said occupant calculated by said occupant acceleration calculating means, the paid-out length of said seat belt detected by said length detecting means, and the position of the occupant in the longitudinal direction of the vehicle detected by said occupant position detecting means.

7. An occupant restraint apparatus according to claim 3, further comprising:

longitudinal and lateral acceleration detecting means for detecting accelerations of the vehicle in longitudinal and lateral directions thereof;

movement direction determining means for determining a direction in which said occupant moves from the accelerations and directions in which the accelerations act, detected by said longitudinal and lateral acceleration detecting means;

said variable load applying means comprising means for varying the load imposed on the paying-out of said seat belt by said impact energy absorbing mechanism further in view of the direction determined by said movement direction determining means.

8. An occupant restraint apparatus for use on a vehicle, comprising:

an impact energy absorbing mechanism for preventing a seat belt from being paid out to restrain an occupant in an emergency and allowing the seat belt to be paid out when a load in excess of a preset load is applied to said seat belt;

length detecting means for detecting a paid-out length of said seat belt when said impact energy absorbing mechanism is operated;

paid-out acceleration calculating means for calculating a paid-out acceleration of said seat belt from the paid-out length detected by said length detecting means;

vehicle acceleration calculating means for detecting a speed of the vehicle with respect to a ground surface on which said vehicle runs and calculating an acceleration of the vehicle with respect to the ground surface, or vehicle acceleration detecting means for detecting an acceleration of the vehicle with respect to the ground surface; and

occupant acceleration calculating means for calculating an acceleration of said occupant with respect to said ground surface based on the calculated paid-out acceleration and the calculated or detected acceleration of the vehicle.

9. An occupant restraint apparatus according to claim 8, further comprising:

angle detecting means for detecting a paid-out angle of said seat belt;

said paid-out acceleration calculating means comprising means for calculating the paid-out acceleration of said seat belt in view of the paid-out angle of said seat belt detected by said angle detecting means.

10. An occupant restraint apparatus according to claim 8, wherein said impact energy absorbing mechanism comprises:

clamp means for clamping said seat belt in an emergency; and

variable load applying means for varying the load imposed on the paying-out of said seat belt by said impact energy absorbing mechanism based on the acceleration of said occupant calculated by said occupant acceleration calculating means.

11. An occupant restraint apparatus according to claim 10, wherein said occupant acceleration calculating means comprises means for calculating a differential with respect to time of the acceleration of the occupant with respect to the ground surface.

12. An occupant restraint apparatus according to claim 10, further comprising:

air bag operation detecting means for detecting operation of an air bag in the vehicle;

said variable load applying means comprising means for varying the load imposed on the paying-out of said seat belt by said impact energy absorbing mechanism based on the acceleration of said occupant calculated by said occupant acceleration calculating means and the operation of the air bag detected by said air bag operation detecting means.

13. An occupant restraint apparatus according to claim 10, further comprising:

occupant position detecting means for detecting the position of the occupant as seated in a longitudinal direction of the vehicle;

said variable load applying means comprising means for varying the load imposed on the paying-out of said seat belt by said impact energy absorbing mechanism based on the acceleration of said occupant calculated by said occupant acceleration calculating means, the paid-out length of said seat belt detected by said length detecting means, and the position of the occupant in the longitudinal direction of the vehicle detected by said occupant position detecting means.

14. An occupant restraint apparatus according to claim 10, further comprising:

longitudinal and lateral acceleration detecting means for detecting accelerations of the vehicle in longitudinal and lateral directions thereof;

movement direction determining means for determining a direction in which said occupant moves from the accelerations and directions in which the accelerations act, detected by said longitudinal and lateral acceleration detecting means;

said variable load applying means comprising means for varying the load imposed on the paying-out of said seat belt by said impact energy absorbing mechanism further in view of the direction determined by said movement direction determining means.

15. A method of controlling an occupant restraint apparatus for use on a vehicle which has an impact energy absorbing mechanism for preventing a seat belt from being paid out to restrain an occupant in an emergency and allowing the seat belt to be paid out when a load in excess of a preset load is applied to said seat belt, comprising the steps of:

detecting a paid-out length of said seat belt when said impact energy absorbing mechanism is operated;

calculating a paid-out speed of said seat belt from the detected paid-out length;

detecting a speed of the vehicle with respect to a ground surface on which said vehicle runs; and

calculating an acceleration of said occupant with respect to said ground surface based on the calculated paid-out speed and the detected speed of the vehicle.

16. A method according to claim 15, further comprising the step of:

calculating the paid-out speed of said seat belt in view of a paid-out angle of said seat belt.

17. A method according to claim 15, further comprising the step of:

calculating a differential with respect to time of the acceleration of the occupant with respect to the ground surface.

18. A method according to claim 15, further comprising the steps of:

detecting operation of an air bag in the vehicle; and

varying the load imposed on the paying-out of said seat belt by said impact energy absorbing mechanism with variable load applying means based on the calculated acceleration of said occupant and the detected operation of the air bag.

19. A method according to claim 15, further comprising the steps of:

detecting the position of the occupant as seated in a longitudinal direction of the vehicle;

varying the load imposed on the paying-out of said seat belt by said impact energy absorbing mechanism with variable load applying means based on the calculated acceleration of said occupant, the detected paid-out length of said seat belt, and the detected position of the occupant in the longitudinal direction of the vehicle.

20. A method according to claim 15, further comprising the steps of:

detecting accelerations of the vehicle in longitudinal and lateral directions thereof;

determining a direction in which said occupant moves from the detected accelerations and directions in which the accelerations act;

varying the load imposed on the paying-out of said seat belt by said impact energy absorbing mechanism with variable load applying means further in view of the determined direction.

21. A method of controlling an occupant restraint apparatus for use on a vehicle which has an impact energy absorbing mechanism for preventing a seat belt from being paid out to restrain an occupant in an emergency and allowing the seat belt to be paid out when a load in excess of a preset load is applied to said seat belt, comprising the steps of:

detecting a paid-out length of said seat belt when said impact energy absorbing mechanism is operated;

calculating a paid-out acceleration of said seat belt from the detected paid-out length;

detecting a speed of the vehicle with respect to a ground surface on which said vehicle runs and calculating an acceleration of the vehicle with respect to the ground surface, or detecting an acceleration of the vehicle with respect to the ground surface; and

calculating an acceleration of said occupant with respect to said ground surface based on the calculated paid-out acceleration and the calculated or detected acceleration of the vehicle.

22. A method according to claim 21, further comprising the step of:

calculating the paid-out acceleration of said seat belt in view of a paid-out angle of said seat belt.

23. A method according to claim 21, further comprising the step of:

calculating a differential with respect to time of the acceleration of the occupant with respect to the ground surface.

24. A method according to claim 21, further comprising the steps of:

detecting operation of an air bag in the vehicle; and

varying the load imposed on the paying-out of said seat belt by said impact energy absorbing mechanism with variable load applying means based on the calculated acceleration of said occupant and the detected operation of the air bag.

25. A method according to claim 21, further comprising the steps of:

detecting the position of the occupant as seated in a longitudinal direction of the vehicle;

varying the load imposed on the paying-out of said seat belt by said impact energy absorbing mechanism with variable load applying means based on the calculated acceleration of said occupant, the detected paid-out length of said seat belt, and the detected position of the occupant in the longitudinal direction of the vehicle.

26. A method according to claim 21, further comprising the steps of:

detecting accelerations of the vehicle in longitudinal and lateral directions thereof;

determining a direction in which said occupant moves from the detected accelerations and directions in which the accelerations act;

varying the load imposed on the paying-out of said seat belt by said impact energy absorbing mechanism with variable load applying means further in view of the determined direction.