Displacement Information Derivation Device, Occupant Restraint System, Vehicle, and Displacement Infromation Derivation Method

• US 20070023224A1
• Filed: 07/27/2006
• Published: 02/01/2007
• Est. Priority Date: 07/27/2005
• Status: Active Grant

• Current Assignee: Joyson Safety Systems Japan K.K.
• Original Assignee: Takata Corporation (Ningbo Junsheng Investment Group Co., Ltd.)
• Inventors: Aoki, Hiroshi, Ooi, Kazuya
• Granted Patent: US 7,614,652 B2
• Time in Patent Office: Days
• US Class Current: 180/274
• CPC Class Codes: B60R 21/0134 responsive to imminent contact with an obstacle , e.g. using radar systems
• CPC Class Codes: B60R 21/0136 responsive to actual contact with an obstacle , e.g. to vehicle deformation, bumper displacement or bumper velocity relative to the vehicle monitoring crash strength in combination with passenger seat detection B60R21/01558
• CPC Class Codes: G01D 5/2046 by a movable ferromagnetic element, e.g. a core

Abstract

A collision detection device is provided which is effective for improving the detection quality for detection of displacement of a vehicle component during a vehicle collision. In one form, the collision detection device to be installed in a vehicle comprises a coil sensor. The coil sensor includes a first coil which is arranged to face a door outer panel and a second coil which is arranged near the first coil and inside the outer diameter of the first coil and centered about a line perpendicular to the coil plane of the first coil. The coil sensor detects information about induced voltage due to magnetovariation via the second coil when the door outer panel is located in a distant region and detects information about variation in impedance via the first coil when the door outer panel is located in an adjacent region.

Claims

1. A collision detection device for a vehicle, the collision detection device comprising:

an electrical power source;

an electronic sensor for detecting displacement of a metallic vehicle component;

a first portion of the sensor driven by the electrical power source to generate a magnetic field in the metallic vehicle component; and

a second portion of the sensor separate and spaced from the first portion, the second portion having a predetermined electrical characteristic that is variable responsive to the displacement of the metallic vehicle component.

2. The collision detection device of claim 1 wherein the electronic sensor comprises a coil sensor.

3. The collision detection device of claim 1 wherein the first and second portions comprise first and second coils, respectively, with the first coil extending about the second coil.

4. The collision detection device of claim 1 wherein the first portion has a predetermined electrical characteristic that is variable responsive to the displacement of the metallic vehicle component, with the first and second portions being arranged and configured so that the second portion is operable to have an optimized response to displacement of the metallic vehicle component at distances further from the electronic sensor than at which the first portion has an optimized response to displacement of the metallic vehicle component.

5. The collision detection device of claim 4 wherein the first portion predetermined electrical characteristic comprises impedance, and the second portion predetermined electrical characteristic comprises induced voltage.

6. The collision detection device of claim 1 wherein the first and second portions comprise first and second coils, respectively, with the second coil having a predetermined impedance that is greater than a predetermined impedance of the first coil.

7. The collision detection device of claim 1 including a control unit that receives information from at least the second portion of the sensor relating to changes in the predetermined electrical characteristic thereof for deriving information relating to the displacement of the metallic vehicle component.

8. The collision detection device of claim 7 in combination with an occupant restraint device for restraining a vehicle occupant during vehicle emergency conditions, with the control unit controlling operation of the occupant restraint device based on the derived information.

9. A displacement detection device, the displacement detection device comprising:

a first electronic sensor portion extending in a generally annular configuration;

a second electronic sensor portion arranged inside of the annularly configured first sensor and cooperating with the first sensor portion such that both the first sensor portion and the second sensor portion detect information regarding displacement of a vehicle component.

10. The displacement detection device of claim 9 wherein the second electronic sensor portion has increased sensitivity to displacement of the vehicle component at greater distances from the first and second electronic sensors than that the first electronic sensor.

11. The displacement detection device of claim 9 wherein the first electronic sensor portion includes a first annularly arranged coil assembly and the second electronic sensor portion includes a second annularly arranged coil assembly and said first coil assembly and said second coil assembly are arranged such that coil centers thereof correspond with each other.

12. The displacement detection device of claim 9 wherein the first and second electronic sensor portions detect information regarding displacement of the vehicle component without deformation thereof.

13. The displacement detection device of claim 9 wherein the displacement information comprises at least one of displacement distance, displacement speed, and displacement acceleration.

14. The displacement detection device of claim 9 in combination with a vehicle having a vehicle door wherein the first and second electronic sensor portions both have an annular configuration being oriented so that axes extending through centers of the annularly configured electronic sensor portions extend transversely to the door.

15. A method of detecting information relating to displacement of a vehicle component, the method comprising:

energizing a first portion of an electronic sensor;

generating a magnetic field in a predetermined metallic vehicle component;

arranging a second portion of the electronic sensor in a predetermined spaced position relative to the first portion;

detecting variation in a predetermined electrical characteristic of the second portion responsive to displacement of the predetermined metallic vehicle component; and

deriving information regarding displacement of the predetermined metallic vehicle component based on the detected variation.

16. The method of claim 15 wherein the magnetic field in the predetermined metallic vehicle component is generated by the energized first portion of the electronic sensor.

17. The method of claim 15 including:

detecting variation in a predetermined electrical characteristic of the first portion responsive to displacement of the predetermined metallic vehicle component; and

optimizing responsiveness of the variation in the predetermined electrical characteristic of the second sensor portion at distances of the vehicle component from the sensor that are greater than distances at which the responsiveness to the variation in the predetermined electrical characteristic of the first portion is optimized.

18. The method of claim 17 wherein the responsiveness of the variation in the predetermined electrical characteristic of the second sensor portion is optimized by configuring the second sensor portion to have a higher impedance than the first sensor portion.

19. The method of claim 15 including arranging the first portion of the sensor to extend about the second portion of the sensor.

20. The method of claim 15 including arranging the first portion to extend in a generally annular configuration, and the second portion is arranged to extend in a generally annular configuration within the annular configuration of the first portion.

21. The method of claim 20 wherein the first and second portions are arranged concentric relative to each other.