Pressure-Based Crash Detection System Incorporated in Side Rail

• US 20120104777A1
• Filed: 10/28/2010
• Published: 05/03/2012
• Est. Priority Date: 10/28/2010
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Ghannam, Mahmoud Y., Clark, Todd N., Stratten, Eric L., Carremm, Swadad A.
• Granted Patent: US 8,398,133 B2
• Time in Patent Office: Days
• US Class Current: 293/133
• CPC Class Codes: B60R 19/34 destroyed upon impact, e.g. one-shot type
• CPC Class Codes: B60R 19/48 combined with, or convertible into, other devices or objects, e.g. bumpers combined with road brushes, bumpers convertible into beds
• CPC Class Codes: B60R 19/483 with obstacle sensors of electric or electronic type

Abstract

A vehicular crash sensing system is provided wherein a bumper cap contacts a bumper. A chamber is at least partially fit into a side rail attached to the bumper, wherein the chamber is sealed by the bumper cap. The bumper cap and chamber together enclose a space containing a volume of air. A stop element limits movement of the chamber into the side rail. A pressure sensor detects an increased chamber air pressure during crushing of the chamber resulting from movement of the bumper with respect to the stop element.

Claims

1. A crash sensing system for a vehicle having a first frame member with a contoured surface and having a second hollow frame member attached to the first frame member, comprising:

a bumper cap having a first end surface shaped to nest into the contoured surface of the first frame member;

an elongated chamber having an outer wall, at least a portion of which is sized to be received in the second hollow frame member, wherein the outer wall has an end opening at a first end for receiving a second end of the bumper cap, and wherein the bumper cap substantially seals the end opening;

a reaction cap substantially closing a second end of the outer wall of the chamber, wherein the reaction cap or the elongated chamber include a stop surface for abutting a reaction surface that is stationary with respect to the second hollow frame member; and

a fluid sensor for detecting a change in the fluid in the chamber caused by crushing of the outer wall in response to a crash force received by the frame members and transmitted through the bumper cap, wherein the outer wall has a side opening for receiving the pressure sensor.

2. The system of claim 1 wherein the first frame member is comprised of a bumper and the second hollow frame member is comprised of a side rail.

3. The system of claim 1 wherein the first frame member is comprised of a bumper and the second hollow frame member is comprised of a crush can.

4. The system of claim 1 wherein the elongated chamber comprises a plurality of circumferential grooves for reducing resistance of the outer wall to being crushed in the longitudinal direction.

5. The system of claim 4 wherein the circumferential grooves are concentrated toward the first end.

6. The system of claim 1 wherein the outer wall is substantially cylindrically shaped.

7. The system of claim 6 wherein the outer wall further comprises a flattened facet proximate to the second end of the outer wall that has the side opening formed therein.

8. The system of claim 1 wherein the reaction cap is comprised of a plate-like member mounted to an inside surface of the outer wall.

9. The system of claim 1 wherein the reaction cap and the outer wall are integrally formed.

10. The system of claim 1 wherein the reaction surface comprises an intrusion integrally formed in the second hollow frame member.

11. The system of claim 1 further comprising a bracket for forming the reaction surface, wherein the bracket is adapted to cross a hollow interior space of the second hollow frame member.

12. The system of claim 11 wherein the bracket is cup-shaped.

13. A vehicular crash sensing system, comprising:

a bumper cap for contacting a bumper;

a chamber for fitting into a side rail attached to the bumper, the chamber being sealed by the bumper cap;

a stop element limiting movement of the chamber into the side rail; and

a pressure sensor for detecting an increased chamber air pressure during crushing of the chamber resulting from movement of the bumper with respect to the stop element.

14. The system of claim 13 wherein the stop element is comprised of an intrusion integrally formed in the side rail.

15. The system of claim 13 wherein the stop element is comprised of a bracket mounted across a hollow interior space of the side rail.

16. The system of claim 13 wherein the chamber comprises a plurality of circumferential grooves for reducing resistance to being crushed in the longitudinal direction.

17. The system of claim 16 wherein the circumferential grooves are concentrated toward an end of the chamber receiving the bumper cap.

18. The system of claim 13 wherein the chamber is substantially cylindrically shaped.

19. The system of claim 18 wherein the chamber comprises a flattened facet proximate to the stop element and having a side opening formed therein for receiving the pressure sensor.

20. The system of claim 13 wherein the chamber includes a reaction cap for sealing the chamber at an end of the chamber proximate to the stop element.