DRIVESHAFT ASSEMBLY WITH TORQUE SENSOR

• US 20100200325A1
• Filed: 02/12/2009
• Published: 08/12/2010
• Est. Priority Date: 02/12/2009
• Status: Active Grant

• Current Assignee: American AXLE & Manufacturing Incorporated (American AXLE & Manufacturing Holdings Incorporated)
• Original Assignee: American AXLE & Manufacturing Incorporated (American AXLE & Manufacturing Holdings Incorporated)
• Inventors: Steyer, Glen C., Marsh, Gregory A.
• Granted Patent: US 7,886,863 B2
• Time in Patent Office: Days
• US Class Current: 180/383
• CPC Class Codes: G01L 3/102 involving magnetostrictive means magnetostrictive sensors H10N35/101
• CPC Class Codes: G01L 3/103 Details about the magnetic material used

Abstract

A driveshaft assembly that includes a first shaft member, a second shaft member, a bearing assembly and a sensor. The first shaft member has a magnetically encoded zone with a magnetic field that varies as a function of the torque that is transmitted through the first shaft member. The second shaft member is coupled for rotation with the first shaft member. The bearing assembly comprises a bearing support, which is configured to be coupled to a vehicle structure, and a bearing that is housed in the bearing support. The bearing journally supports the first shaft member for rotation about a first axis. The sensor is coupled to the bearing assembly. The sensor is arranged to sense the magnetic field of the magnetically encoded zone and responsively produce an electrical signal.

Claims

1. A driveshaft assembly comprising:

a first shaft member having a magnetically encoded zone having a magnetic field that varies as a function of the torque that is transmitted through the first shaft member;

a second shaft member coupled for rotation with the first shaft member;

a bearing assembly that comprises a bearing support, which is adapted to be coupled to a vehicle structure, and a bearing that is housed in the bearing support and journally supports the first shaft member for rotation about a first axis; and

a sensor coupled to the bearing assembly and arranged to sense the magnetic field of the magnetically encoded zone and responsively produce an electrical signal.

2. The driveshaft assembly of claim 1, wherein the bearing assembly comprises a resilient mount that is disposed between the bearing support and the bearing.

3. The driveshaft assembly of claim 1, further comprising a processor and a display, the processor receiving the electrical signal and being configured to cause the display to display a value that is indicative of a magnitude of a torque that is transmitted through the first shaft member.

4. The driveshaft assembly of claim 1, further comprising a slip yoke coupled to the first shaft member.

5. The driveshaft assembly of claim 4, wherein the magnetically encoded zone is disposed between the bearing assembly and the slip yoke.

6. The driveshaft assembly of claim 5, wherein one of the first shaft member and the slip yoke includes a male splined end and the other one of the first shaft member and the slip yoke includes a female splined end that is engaged to the male splined end.

7. The driveshaft assembly of claim 1, wherein the magnetically encoded zone is formed of a material that consists of 2 percent by weight to 6 percent by weight nickel.

8. A vehicle comprising:

a powertrain having a powertrain output;

an axle assembly having an input pinion;

a body to which the powertrain and axle assembly are coupled;

a driveshaft assembly coupling the powertrain output and the input pinion to transmit rotary power to the input pinion, the driveshaft assembly comprising a first shaft member, a second shaft member, a bearing assembly and a sensor, the first shaft member having a magnetically encoded zone with a magnetic field that varies as a function of the torque that is transmitted through the first shaft member, the second shaft member being coupled for rotation with the first shaft member, the bearing assembly having a bearing support, which is coupled to the body, and a bearing that is housed in the bearing support and journally supports the first shaft member for rotation about a first axis, the sensor being coupled to the bearing assembly and arranged to sense the magnetic field of the magnetically encoded zone and responsively produce an electrical signal.

9. The driveshaft assembly of claim 8, wherein the bearing assembly comprises a resilient mount that is disposed between the bearing support and the bearing.

10. The driveshaft assembly of claim 8, further comprising a processor and a display, the processor receiving the electrical signal and being configured to cause the display to display a value that is indicative of a magnitude of a torque that is transmitted through the first shaft member.

11. The driveshaft assembly of claim 8, further comprising a slip yoke coupled to the first shaft member.

12. The driveshaft assembly of claim 11, wherein the magnetically encoded zone is disposed between the bearing assembly and the slip yoke.

13. The driveshaft assembly of claim 12, wherein one of the first shaft member and the slip yoke includes a male splined end and the other one of the first shaft member and the slip yoke includes a female splined end that is engaged to the male splined end.

14. The driveshaft assembly of claim 8, wherein the magnetically encoded zone is formed of a material that consists of 2 percent by weight to 6 percent by weight nickel.

15. The driveshaft assembly of claim 8, wherein multiple sensors are coupled to the bearing assembly.

16. The driveshaft assembly of claim 15, wherein the multiple sensors are angled at various degrees around the driveshaft to sense a portion of the magnetic field of the magnetically encoded zone and responsively produce an electrical signal for the portion of the magnetic field.

17. An axle shaft assembly comprising:

a first shaft member having a magnetically encoded zone having a magnetic field that varies as a function of the torque that is transmitted through the first shaft member;

a second shaft member coaxially aligned with the first shaft member; and

a sensor coupled to the second shaft member and arranged to sense the magnetic field of the magnetically encoded zone and responsively produce an electrical signal.

18. The axle shaft assembly of claim 17, further comprising a processor and a display, the processor receiving the electrical signal and being configured to display a value that is indicative of a magnitude of the torque that is transmitted through the first shaft member.

19. The axle shaft assembly of claim 17, wherein the magnetically encoded zone is formed of a material that consists of 2 percent by weight to 6 percent by weight nickel.

20. The axle shaft assembly of claim 17, wherein the sensor senses the magnetic field of the magnetically encoded zone through the second shaft member.