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

• US 7,147,261 B2
• Filed: 07/18/2002
• Issued: 12/12/2006
• Est. Priority Date: 07/18/2001
• Status: Expired due to Fees

• Current Assignee: Intier Automotive, Incorporated (Magna International Incorporated)
• Original Assignee: Intier Automotive, Incorporated (Magna International Incorporated)
• Inventors: Ventura, Kevin J., Tokarz, Stephen P.
• Primary Examiner(s): Dayoan, D. Glenn
• Assistant Examiner(s): CHENEVERT, PAUL A
• Application Number:
  US10/484,365
• Publication Number:
  US 20040239086A1
• Time in Patent Office: 1,608 Days
• Field of Search: 296/65.01, 296/68.1, 296/65.13, 296/65.14, 428/429, 428/224, 428/550, 248/429, 248/550
• US Class Current: 296/65.13
• 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 longitudinally along a portion of said length of said movable rail, said elongated body comprising a metallic strip having a portion thereof completely encased in a thermoplastic material along the longitudinal length of the metallic strip thereby defining a ferromagnetic surface adjacent a non-ferromagnetic surface; and

a magnetic sensor fixedly secured to said stationary rail and disposed adjacent said shunt to determine a magnetic field strength and responsively produce a position signal indicating a position of said sensor relative to said shunt whereby said sensor sand 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 non-ferromagnetic surface is disposed adjacent to and co-planar with said ferromagnetic surface.

7. A seat track assembly as set forth in claim 6 wherein said shunt defines an interface between said ferromagnetic surface and said non-ferromagnetic surface.

8. A seat track assembly as set forth in claim 7 wherein said sensor is fixedly secured to said lower cross member.

9. A seat track assembly as set forth in claim 8 wherein said sensor includes a sensor bracket for fixedly securing said sensor to said stationary rail.

10. A seat track assembly as set forth in claim 9 wherein said movable rail includes outer sides and an upper cross member.

11. A seat track assembly as set forth in claim 10 wherein said shunt is positioned between said outer sides.

12. A seat track assembly as set forth in claim 11 wherein said shunt is fixedly secured to said upper cross member.

13. A seat track assembly as set forth in claim 12 wherein said shunt includes a flange for fixedly securing said shunt to said movable rail.

14. A seat track assembly as set forth in claim 13 wherein said movable rail includes a stop extending therethrough.

15. A seat track assembly as set forth in claim 1 wherein said shunt has a ratio of ferromagnetic surface to non-ferromagnetic surface of about 40 to 60.

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 longitudinally along a portion of said length of said stationary rail, said elongated body comprising a metallic strip having a portion thereof completely encased in a thermoplastic material along the longitudinal length of the metallic strip thereby defining a ferromagnetic surface adjacent a non-ferromagnetic surface;

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

a magnetic sensor disposed adjacent said shunt to determine a magnetic field strength and responsively 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 defines an interface between said ferromagnetic surface and said non-ferromagnetic surface.

18. A seat track assembly as set forth in claim 17 wherein said movable rail includes outer sides and an upper cross member.

19. A seat track assembly as set forth in claim 18 wherein said sensor is fixedly secured to said movable rail.

20. A seat track assembly as set forth in claim 19 wherein said sensor is positioned between said outer sides.

21. A seat track assembly as set forth in claim 20 wherein said sensor includes a sensor cross member and sensor sides extending perpendicularly therefrom.

22. A seat track assembly as set forth in claim 21 wherein said sensor sides extend down on either side of said shunt.