Method for Controlling a Belt Pretensioner and Safety Arrangement Comprising a Belt Pretensioner

• US 20080300753A1
• Filed: 07/11/2006
• Published: 12/04/2008
• Est. Priority Date: 07/30/2005
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust)
• Inventors: Rick, Ulrich, Kettern-Kohler, Horst, Bauer, Klaus, Hesse, Simon
• Granted Patent: US 8,335,614 B2
• Time in Patent Office: Days
• US Class Current: 701/45
• CPC Class Codes: B60R 2021/01272 Belt tensioners
• CPC Class Codes: B60R 2021/01313 monitoring the vehicle steering system or the dynamic control system
• CPC Class Codes: B60R 2021/01327 Angular velocity or angular acceleration
• CPC Class Codes: B60R 21/0132 responsive to vehicle motion parameters , e.g. to vehicle longitudinal or transversal deceleration or speed value

Abstract

The present invention relates to a method for controlling a reversible seat belt pretensioner in a motor vehicle, comprising the steps of detecting the speed and the steering angle of the vehicle, calculating an expected turning rate of the vehicle about its vertical axis from the speed and the steering angle and calculating an upper and a lower turning rate limiting value using the expected turning rate, detecting the actual turning rate of the vehicle about its vertical axis and activating the seat belt pretensioner of the vehicle if the actual turning rate of the vehicle is greater than the upper turning rate limiting value or is less than the lower turning rate limiting value. The present invention also relates to a safety arrangement for implementing the method according to the invention.

Claims

1. A method for controlling a reversible seat belt pretensioner in a motor vehicle, comprising the steps:

detecting the speed and the steering angle of the vehicle;

calculating an expected turning rate of the vehicle about its vertical axis from the speed and the steering angle;

calculating an upper and a lower turning rate limiting value using the expected turning rate;

detecting the actual turning rate of the vehicle about its vertical axis; and

activating the seat belt pretensioner of the vehicle if the actual turning rate of the vehicle is greater than the upper turning rate limiting value or is less than the lower turning rate limiting value.

2. The method according to claim 1, wherein the seat belt pretensioner is only activated if the actual turning rate of the vehicle is greater than or less than the upper or lower turning rate limiting value respectively for a predetermined period of time.

3. The method according to claim 2, wherein the predetermined period of time is established as a function of the speed of the vehicle.

4. The method according to claim 3, wherein the higher the vehicle speed, the shorter the predetermined period of time.

5. The method according to claim 1, wherein the seat belt pretensioner is only activated if the speed of the vehicle is higher than a predetermined speed limiting value.

6. The method according to claim 1, wherein the upper or lower turning rate limiting value is calculated by multiplying the expected turning rate by a first or second tolerance factor respectively, the first tolerance factor being greater than about 1 and the second tolerance factor being less than about 1.

7. The method according to claim 1, further comprising the step of deactivating the activated seat belt pretensioner when the actual turning rate of the vehicle is again less than the upper turning rate limiting value and greater than the lower turning rate limiting value.

8. A safety arrangement for a motor vehicle comprising:

a reversible seat belt pretensioner;

a detection device for detecting the speed, the steering angle and the actual turning rate of the vehicle; and

a control device by means of which it is possible to activate and deactivate the seat belt pretensioner, wherein a calculation device is provided by means of which it is possible to calculate an expected turning rate of the vehicle about its vertical axis from the speed and the steering angle and an upper and lower turning rate limiting value using the expected turning rate, wherein the control device cooperates with the seat belt pretensioner such that it is possible to activate the seat belt pretensioner if the actual turning rate of the vehicle is greater than the upper turning rate limiting value or less than the lower turning rate limiting value.

9. The safety arrangement according to claim 8, wherein it is only possible to activate the seat belt pretensioner if the actual turning rate of the vehicle is greater than, or less than, the upper, or lower, turning rate limiting value respectively for a predetermined period of time.

10. The safety arrangement according to claim 9, wherein the predetermined period of time can be varied as a function of the speed of the vehicle.

11. The safety arrangement according to claim 10, wherein the predetermined period of time can be reduced by increasing the speed of the vehicle.

12. The safety arrangement according to claim 8, wherein it is only possible to activate the seat belt pretensioner, when the speed of the vehicle is higher than a predetermined speed limiting value.

13. The safety arrangement according to claim 8, wherein it is possible to calculate the upper, or the lower, turning rate limiting value by multiplying the expected turning rate with a first, or a second, tolerance factor respectively, the first tolerance factor being greater than 1 and the second tolerance factor being less than 1.

14. The safety arrangement according to claim 8, wherein it is possible to deactivate the activated seat belt pretensioner when the actual turning rate of the vehicle is again less than the upper turning rate limiting value and greater than the lower turning rate limiting value.