SEAT-BELT PRETENSIONER ARRANGEMENT

• US 20080033616A1
• Filed: 10/08/2007
• Published: 02/07/2008
• Est. Priority Date: 04/07/2005
• Status: Active Grant

• Current Assignee: Autoliv Development AB (Autoliv Incorporated)
• Original Assignee: Autoliv Development AB (Autoliv Incorporated)
• Inventors: GILLET, CHRISTOPHE
• Granted Patent: US 7,624,833 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 21/013 including means for detecting collisions, impending collisions or roll-over

Abstract

A seat-belt pretensioner arrangement includes a pretensioner configured to apply at least two tension levels to a seat-belt and a control system to control the pretensioner. A control system is configured to provide at least one vehicle slip function which is derived from at least one sensed parameter relating to the current or expected dynamic situation of the vehicle. The control system is configured to select the tension level to be applied to the seat-belt by the pretensioner in response to the value of the slip function provided by the control system.

Claims

1. A seat belt pretensioner arrangement for a vehicle, the arrangement comprising a pretensioner configured to apply at least two tension levels to a seat-belt and a control system for controlling the pretensioner, wherein the control system is configured to provide at least one slip function which is derived from at least two sensed parameters relating to a slip condition, of the vehicle, the control system further being configured to select a tension level to be applied to the seat-belt by the pretensioner in response to a value of the slip function provided by the control system.

2. The arrangement according to claim 1 wherein the control system includes at least one processor for processing signals from a plurality of at least two sensors to generate the slip function.

3. The arrangement according to claim 2 wherein at least two of the sensors sense parameters related to slip.

4. The arrangement according to claim 3 wherein the sensors sense two or more parameters selected from the group consisting of longitudinal velocity (v_x), lateral acceleration (a_y), angular velocity (yaw) (ω

_z), and steering angle (δ

).

5. The arrangement according to claim 2 wherein the processor generates a function (f_o/u) indicative of slip conditions in the form of over-steer or under-steer of the vehicle.

6. The arrangement according to claim 2 wherein the processor generates a function (f_bs) indicative of body slip of the vehicle.

7. The arrangement according to claim 2 wherein the processor generates a function (f_ern) indicative of evasive maneuvering of the vehicle.

8. The arrangement according to claim 7 wherein the function (f_ern) indicative of evasive maneuvering is a function of axial velocity (v_x), steering angle (δ

) and rate of change of steering angle (δ

).

9. The arrangement according to claim 2 wherein the processor generates a function (f_hsc) indicative of high speed cornering of the vehicle.

10. The arrangement according to claim 1 further comprising wherein a discriminator for selecting one out of a plurality of slip functions.

11. The arrangement according to claim 1 wherein the at least one slip function is selected from a group consisting of over-steer, under-steer, body slip, evasive maneuvering and high speed cornering.

12. The arrangement according to claim 1 wherein the control system includes a comparator configured to compare the at least one slip function with a first threshold and at least one additional successively increasing threshold, the control system being configured to control the pretensioner to further increase the tension in the seat-belt as each successive threshold is passed.

13. The arrangement according to claim 12 wherein there are at least three thresholds.

14. The arrangement according to claim 1 wherein the control system includes a comparator configured to compare the at least one slip function with a first threshold and to provide an output when said first threshold is exceeded, the output then increasing in a predetermined manner in response to a further increase in value of the slip function, the control system being configured to control the pretensioner to increase the tension in the seat-belt in response to said increased output.

15. The arrangement according to claim 14 wherein the output of the comparator increases smoothly, the control system being configured to control the pretensioner to increase the tension in the seat-belt smoothly in response to said smooth output.

16. The arrangement according to claim 12 wherein the control system is configured to maintain a maximum applied tension in the seat-belt until a predetermined period of time has elapsed after the slip function has fallen below at least one of the thresholds.

17. A seat belt pretensioner arrangement for a vehicle, the arrangement comprising a pretensioner configured to apply at least two tension levels to a seat-belt and a control system for controlling the pretensioner, the control system including at least one processor to process signals from two or more sensors which sense parameters related to a slip situation of the vehicle to generate a plurality of slip functions, the control system including a discriminator for selecting one out of the plurality of slip functions where the slip functions are selected from a group consisting of over-steer/under-steer, body slip, evasive maneuvering and high speed cornering, the control system further being configured to select the tension level to be applied to the seat-belt by the pretensioner in response to a value of one the slip functions provided by the control system, the control system including a comparator configured to compare one of the slip functions with a first threshold and at least one additional successively increasing threshold, the control system being configured to control the pretensioner to further increase the tension in the seat-belt as each successive threshold is passed.