Seat track assembly for a motor vehicle having an integrated position sensor

• US 20040239086A1
• Filed: 07/09/2004
• Published: 12/02/2004
• Est. Priority Date: 07/18/2001
• Status: Active Grant

• Current Assignee: Intier Automotive, Incorporated (Magna International Incorporated)
• Original Assignee: Intier Automotive, Incorporated (Magna International Incorporated)
• Inventors: Ventura, Kevin J., Tokarz, Stephen P
• Granted Patent: US 7,147,261 B2
• Time in Patent Office: Days
• US Class Current: 280/735
• CPC Class Codes: B60N 2/002 Seats provided with an occupancy detection means mounted therein or thereon detection means responsive to presence or absence of children B60N2/266
• CPC Class Codes: B60N 2/0244 with logic circuits
• CPC Class Codes: B60N 2/0705 omega-shaped
• CPC Class Codes: B60N 2/0715 C or U-shaped
• CPC Class Codes: B60N 2210/14 Inductive; Magnetic field
• CPC Class Codes: B60R 21/01554 Seat position sensors

Abstract

A seat track assembly for a seat of a motor vehicle having a floor and an airbag. The seat track assembly includes a stationary rail fixedly secured to the floor. The seat track assembly also includes a movable rail fixedly secured to the seat and slidably engaged with the stationary rail to move the seat therealong. The movable rail extends along a length between a forward position and a rearward position. A shunt defining an elongated body extends along a portion of the length of the movable rail. A sensor is fixedly secured to the stationary rail and disposed adjacent the shunt to produce a position signal indicating a position of the sensor relative to the shunt. The sensor and the shunt are disposed within the stationary and movable rails to be protected thereby.

Claims

1. A seat track assembly for a seat of a motor vehicle having a floor and an airbag, said seat track assembly comprising:

a stationary rail fixedly secured to the floor;

a movable rail fixedly secured to the seat and slidably engaged with said stationary rail to move the seat therealong, said movable rail extending along a length between a forward position and a rearward position;

a shunt defining an elongated body extending along a portion of said length of said movable rail; and

a sensor fixedly secured to said stationary rail and disposed adjacent said shunt to produce a position signal indicating a position of said sensor relative to said shunt whereby said sensor and said shunt are disposed within said stationary and movable rails to be protected thereby.

2. A seat track assembly as set forth in claim 1 wherein said stationary rail includes inner sides and a lower cross member extending between said inner sides.

3. A seat track assembly as set forth in claim 2 wherein said sensor is secured to said stationary rail between said inner sides.

4. A seat track assembly as set forth in claim 3 wherein said sensor includes a sensor cross member and sensor sides extending perpendicularly therefrom.

5. A seat track assembly as set forth in claim 4 wherein said sensor sides extend up on either side of said shunt.

6. A seat track assembly as set forth in claim 5 wherein said shunt includes a ferromagnetic surface.

7. A seat track assembly as set forth in claim 6 wherein said shunt includes a non-ferromagnetic surface disposed adjacent to and co-planar with said ferromagnetic surface.

8. A seat track assembly as set forth in claim 7 wherein said shunt defines an interface between said ferromagnetic surface and said non-ferromagnetic surface.

9. A seat track assembly as set forth in claim 8 wherein said sensor is fixedly secured to said lower cross member.

10. A seat track assembly as set forth in claim 9 wherein said sensor includes a sensor bracket for fixedly securing said sensor to said stationary rail.

11. A seat track assembly as set forth in claim 10 wherein said movable rail includes outer sides and an upper cross member.

12. A seat track assembly as set forth in claim 11 wherein said shunt is positioned between said outer sides.

13. A seat track assembly as set forth in claim 12 wherein said shunt is fixedly secured to said upper cross member.

14. A seat track assembly as set forth in claim 13 wherein said shunt includes a flange for fixedly securing said shunt to said movable rail.

15. A seat track assembly as set forth in claim 14 wherein said movable rail includes a stop extending therethrough.

16. A seat track assembly for a seat of a motor vehicle having a floor and an airbag, said seat track assembly comprising:

a stationary rail fixedly secured to the floor and extending along a length between a front end and a back end;

a shunt fixedly secured to said stationary rail, said shunt defining an elongated body extending along a portion of said length of said stationary rail;

a movable rail fixedly secured to the seat and slidably engaged with said stationary rail to move the seat therealong; and

a sensor disposed adjacent said shunt to produce a position signal indicating a position of said sensor relative to said shunt whereby said sensor and said shunt are disposed within said stationary and movable rails to be protected thereby.

17. A seat track assembly as set forth in claim 16 wherein said shunt includes a ferromagnetic surface.

18. A seat track assembly as set forth in claim 17 wherein said shunt includes a non-ferromagnetic surface.

19. A seat track assembly as set forth in claim 18 wherein said shunt defines an interface between said ferromagnetic surface and said non-ferromagnetic surface.

20. A seat track assembly as set forth in claim 19 wherein said movable rail includes outer sides and an upper cross member.

21. A seat track assembly as set forth in claim 20 wherein said sensor is fixedly secured to said movable rail.

22. A seat track assembly as set forth in claim 21 wherein said sensor is positioned between said outer sides.

23. A seat track assembly as set forth in claim 22 wherein said sensor includes a sensor cross member and sensor sides extending perpendicularly therefrom.

24. A seat track assembly as set forth in claim 23 wherein said sensor sides extend down on either side of said shunt.

25. A method for controlling a deployment rate of an airbag of a motor vehicle having a seat and a seat track assembly including a stationary rail, a sensor disposed within the stationary rail, a movable rail, and a shunt disposed within the movable rail, the method comprising the steps of:

sensing a magnetic field using the sensor and the shunt;

producing a position signal indicating the position of the seat based on the magnetic field sensed by the sensor; and

varying the deployment rate of the airbag based upon the position signal.

26. A method as set forth in claim 25 including the step of sending the position signal to a controller during the step of varying the deployment rate of the airbag based upon the position signal.

27. A method as set forth in claim 26 including the step of sending a control signal from the controller to an airbag controller during the step of varying the deployment rate of the airbag based upon the position signal.

28. A method as set forth in claim 27 including the step of sliding the shunt along the sensor during the step of sensing the position of the sensor relative to the shunt.