Control system for occupant protection apparatus

• US 6,363,307 B1
• Filed: 09/08/2000
• Issued: 03/26/2002
• Est. Priority Date: 09/14/1999
• Status: Expired due to Fees

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Ikegami, Kenji
• Primary Examiner(s): NGUYEN, TAN QUANG
• Application Number:
  US09/657,526
• Time in Patent Office: 564 Days
• Field of Search: 701/45, 701/46, 701/47, 280/735, 280/736, 280/728.1, 280/734, 280/742
• US Class Current: 701/45
• CPC Class Codes: B60R 21/0133 by integrating the amplitude of the input signal
• CPC Class Codes: B60R 21/0156 by deceleration
• CPC Class Codes: B60R 21/017 including arrangements for providing electric power to safety arrangements or their actuating means, e.g. to pyrotechnic fuses or electro-mechanic valves

Abstract

A control system is provided for an occupant protection apparatus including one or more air bags. The control system is capable of avoiding an increase in manufacturing costs by minimizing the number of components and by utilizing a common circuit portion in a pair of activation circuits, while maintaining a rated current substantially equal to that of completely separate activation circuits. If a collision of a vehicle occurs, first and second activation circuits are activated based on an integrated value ΔV of a deceleration measured with the G-sensor. If an activation time period of the second activation circuit happens to overlap with an activation time period of the first activation circuit, a control unit activates the second activation circuit upon completion of the activation of the first activation circuit. Therefore, the number of components of the control system can be reduced. Also, since the first and second activation circuits are not activated at the same time, a portion of the activation circuits that is common to both of the first and second activation circuits can be inside of a circuit that has the same capacity as conventional circuits.

Claims

1. A control system for an occupant protection apparatus of a vehicle comprising:

first and second activating devices adapted to activate the occupant protecting apparatus;

a control unit operatively coupled to said first and second activating devices, said control unit including a collision diagnostic portion that determines a level of a collision of the vehicle based on deceleration of the vehicle during the collision;

a deceleration sensor operatively coupled to said control unit to provide information on the deceleration of the vehicle during the collision;

a first activation circuit operatively coupling said control unit to said first activating device; and

a second activation circuit operatively coupling said control unit to said second activating device, said first and second activation circuits share a commonly connected portion;

said control unit selectively energizing at least one of said first and second activation circuits to selectively activate at least one of first and second activating devices for first and second predetermined activation time periods, respectively, based on said level of the collision determined with said collision diagnostic portion,

said control unit being configured to receive a first activation requirement signal from said collision diagnostic portion to activate said first activating device and a second activation requirement signal from said collision diagnostic portion to activate said second activating device when said level of the collision determined by said collision diagnostic portion requires activation of both said first and second activation circuits, said control unit selectively activates said second activation circuit after completion of said first predetermined activation time period of said first activation circuit, when said second activation requirement signal overlaps with said first activation requirement signal.

2. A control system for an occupant protection apparatus according to claim 1, wherein

said commonly connected portion of said first and second activation circuits is located on an upstream side of said first and second activating devices.

3. A control system for an occupant protection apparatus according to claim 1, wherein

said commonly connected portion of said first and second activation circuits is located on an downstream side of said first and second activating devices.

4. A control system for an occupant protection apparatus according to claim 1, wherein

said control unit includes a microprocessor operatively coupled to said deceleration sensor and said first and second activation circuits.

5. A control system for an occupant protection apparatus according to claim 4, wherein

said microprocessor calculates an integrated value of deceleration measured by said deceleration sensor.

6. A control system for an occupant protection apparatus according to claim 5, wherein

said microprocessor compares said integrated value with a first threshold value and energizes said first activation circuit for said first predetermined activation time period to activate said first activating device if said integrated value is equal to or greater than said first threshold value.

7. A control system for an occupant protection apparatus according to claim 6, wherein

said microprocessor compares said integrated value with a second threshold value if said integrated value is equal to or greater than said first threshold value, and energizes said second activation circuit for said second predetermined activation time period to activate said second activating device if said integrated value is equal to or greater than said second threshold value and immediately after said first predetermined activation time period has lapsed.

8. A control system for an occupant protection apparatus according to claim 6, wherein

said microprocessor compares said integrated value with a second threshold value if said integrated value is equal to or greater than said first threshold value, and energizes said second activation circuit for said second predetermined activation time period to activate said second activating device if said integrated value is equal to or greater than said second threshold value and a third predetermined period of time has lapsed after said first predetermined activation time period has lapsed.

9. A control system for an occupant protection apparatus according to claim 6, wherein

said microprocessor energizes said second activation circuit for said second predetermined activation time period to activate said second activating device immediately after said first predetermined activation time period has lapsed.

10. A control system for an occupant protection apparatus according to claim 6, wherein

said microprocessor energizes said second activation circuit for said second predetermined activation time period to activate said second activating device after said first predetermined activation time period has lapsed and after an additional predetermined period of time has lapsed.

11. A control system for an occupant protection apparatus according to claim 1, further comprising

an air bag operatively coupled to said first and second activating devices.

12. A control system for an occupant protection apparatus according to claim 1, further comprising

a first air bag operatively coupled to said first activating device;

and a second airbag operatively coupled to said second activating device.

13. A control system for an occupant protection apparatus of a vehicle comprising:

occupant protecting means having at least first and second activating means; and

control means for controlling said occupant protection apparatus, which protects a vehicle occupant with said occupant protecting means, said control means including

deceleration sensor means for measuring a deceleration of a vehicle;

collision diagnostic means for determining a level of vehicle collision impact based on said deceleration measured with said deceleration sensor means;

a first activation circuit for activating said first activating means; and

a second activation circuit for activating said second activating means, said first and second activation circuits sharing a commonly connected portion;

said control means selectively energizing at least one of said first and second activation circuits to selectively activate at least one of first and second activating devices for first and second predetermined activation time periods, respectively, based on said level of vehicle collision impact determined with said collision diagnostic means,

said control means being configured to receive a first activation requirement signal from said collision diagnostic means to activate said first activating device and a second activation requirement signal from said collision diagnostic means to activate said second activating device when said level of the collision determined by said collision diagnostic means requires activation of both said first and second activation circuits, said control means selectively activates said second activation circuit upon completion of said first predetermined activation time period of said first activation circuit, when said second activation requirement signal overlaps with said first activation requirement signal.

14. A control system for an occupant protection apparatus according to claim 13, wherein

said control means includes calculating means for calculating an integrated value of deceleration measured by said deceleration sensor means.

15. A control system for an occupant protection apparatus according to claim 14, wherein

said calculating means compares said integrated value with a first threshold value and said control means energizes said first activation circuit for said first predetermined activation time period to activate said first activating means if said integrated value is equal to or greater than said first threshold value.

16. A control system for an occupant protection apparatus according to claim 15, wherein

said calculating means compares said integrated value with a second threshold value if said integrated value is equal to or greater than said first threshold value, and said control means energizes said second activation circuit for said second predetermined activation time period to activate said second activating means if said integrated value is equal to or greater than said second threshold value and immediately after said first predetermined activation time period has lapsed.

17. A control system for an occupant protection apparatus according to claim 15, wherein

said calculating means compares said integrated value with a second threshold value if said integrated value is equal to or greater than said first threshold value, and said control means energizes said second activation circuit for said second predetermined activation time period to activate said second activating means if said integrated value is equal to or greater than said second threshold value and a third predetermined period of time has lapsed after said first predetermined activation time period has lapsed.

18. A control system for an occupant protection apparatus according to claim 15, wherein

said control means energizes said second activation circuit said second predetermined activation time period to activate said second activating means immediately after said first predetermined activation time period has lapsed.

19. A control system for an occupant protection apparatus according to claim 15, wherein

said control means energizes said second activation circuit for said second predetermined activation time period to activate said second activating means after said first predetermined activation time period has lapsed and after an additional predetermined period of time has lapsed.