SEAT BELT RETRACTOR SYSTEM

• US 20060226648A1
• Filed: 04/07/2005
• Published: 10/12/2006
• Est. Priority Date: 04/07/2005
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Kalina, Curtis, Rao, Manoharprasad K., Cuddihy, Mark
• Granted Patent: US 7,343,999 B2
• Time in Patent Office: Days
• US Class Current: 280/806
• CPC Class Codes: B60R 2022/4666 characterised by electric actuators
• CPC Class Codes: B60R 2022/4685 with means to adjust or regulate the tensioning force in relation to external 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 21/01544 detecting seat belt parameters, e.g. length, tension or height-adjustment
• CPC Class Codes: B60R 22/195 with means to tension the belt in an emergency, e.g. means of the through-anchor or splitted reel typeelectrical circuits for triggering safety arrangements B60R21/01

Abstract

A seat belt retractor system and a method of controlling the seat belt retractor system. The seat belt is retracted at a faster rate when a threat is detected using a high-voltage generated by a local power source.

Claims

1. A seat belt retractor system for a vehicle having a vehicle safety system adapted to provide a signal indicative of potential injury to a vehicle occupant, the seat belt retractor system comprising:

a seat belt;

a retractor mechanism disposed proximate the vehicle and having a motor adapted to retract the seat belt; and

a control circuit for controlling operation of the motor, the control circuit being connected to first and second voltage sources, the second voltage source configured to provide a higher voltage level than the first voltage source;

wherein the motor is driven by the second voltage source to retract the seat belt when the signal is indicative of potential injury to the vehicle occupant, and the second voltage source is charged by the first voltage source when the signal is not indicative of potential injury to the vehicle occupant.

2. The system of claim 1 wherein the second voltage source is a capacitor.

3. The system of claim 1 further comprising a charge pump connected to the first voltage source, the charge pump being configured to step up voltage provided by the first voltage source to charge the second voltage source.

4. The system of claim 3 wherein the first voltage source is associated with a vehicle electrical system and the charge pump acts a current limiter to inhibit drawing an increased level of current from the vehicle electrical system when the motor is driven by the second voltage source.

5. The system of claim 1 further comprising first and second vehicle safety systems adapted to provide first and second signals, respectively, wherein the control circuit provides voltage at a first elevated voltage level to drive the motor when the first signal is indicative of potential injury to the vehicle occupant and provides voltage at a second elevated voltage level to drive the motor when the second signal is indicative of potential injury to the vehicle occupant.

6. A method of controlling a seat belt retractor system for a motor vehicle having a vehicle safety system, the seat belt retractor system having a seat belt, a motor adapted to retract the seat belt, and first and second voltage sources adapted to power the motor, the method comprising:

generating a first signal indicative of a state of charge of the second voltage source;

generating a second signal indicative of a status of the vehicle safety system; and

determining whether to provide power to the motor with the first voltage source or the second voltage source to retract the seat belt based on the first and second signals.

7. The method of claim 6 wherein power is provided to the motor with the first voltage source when the state of charge of the second voltage source is less than a predetermined voltage level or the second signal is not indicative of potential injury to a vehicle occupant.

8. The method of claim 6 further comprising providing power to the motor with the second voltage source when the state of charge of the second voltage source is greater than a predetermined voltage level and the second signal is indicative of potential injury to a vehicle occupant.

9. The method of claim 8 wherein power is provided to the motor by the second voltage source for a predetermined period of time.

10. The method of claim 8 wherein power is provided to the motor by the second voltage source for a predetermined period of time or until stalling of the motor is detected.

11. The method of claim 6 wherein the second voltage source is charged with the first voltage source when the second signal is not indicative of potential injury to a vehicle occupant.

12. The method of claim 6 wherein the vehicle safety system is an impact detection system.

13. The method of claim 6 wherein the vehicle safety system is a collision warning system.

14. The method of claim 6 wherein the vehicle safety system is a vehicle dynamics system adapted to detect instability of the vehicle.

15. The method of claim 6 wherein the vehicle safety system is a vehicle brake system and the second signal is based on actuation of a brake pedal.

16. A method of controlling a seat belt retractor system for a motor vehicle having first and second vehicle safety systems, the seat belt retractor system having a seat belt, a motor adapted to retract the seat belt, and a control circuit adapted to control voltage provided to the motor, the method comprising:

generating first and second signals indicative of a status of the first and second vehicle safety systems, respectively;

driving the motor at a first elevated voltage level to retract the seat belt at a first elevated rate when the first signal is indicative of potential injury to a vehicle occupant; and

driving the motor at a second elevated voltage level to retract the seat belt at a second elevated rate when the second signal is indicative of a potential injury to a vehicle occupant.

17. The method of claim 16 wherein the first elevated rate is less than the second elevated rate.

18. The method of claim 16 wherein the motor is driven at the first or second elevated voltage levels for a predetermined period of time or until stalling of the motor is detected.

19. The method of claim 16 wherein the seat belt retractor system further comprises a capacitor and the step of driving the motor at the second elevated voltage level further comprises determining a state of charge of the capacitor and driving the motor at the second elevated voltage level when the state of charge exceeds a predetermined voltage level.

20. The method of claim 16 wherein the seat belt retractor system further comprises a voltage source and the capacitor is charged by the voltage source when the first and second signals are not indicative of potential injury to a vehicle occupant.