Sensorized bearing unit

• US 8,313,240 B2
• Filed: 03/12/2007
• Issued: 11/20/2012
• Est. Priority Date: 03/12/2007
• Status: Expired due to Fees

• Current Assignee: ABet SKF
• Original Assignee: ABet SKF
• Inventors: Giordana, Davide
• Primary Examiner(s): Johnson, Phillip A
• Application Number:
  US12/450,121
• Publication Number:
  US 20100074567A1
• Time in Patent Office: 2,080 Days
• Field of Search: 384/448, 384/462, 384/476, 734/93, 735/143.1, 735/143.9, 324/207.25, 324/173, 324/174
• US Class Current: 384/448
• CPC Class Codes: F16C 19/163 with angular contact
• CPC Class Codes: F16C 19/52 with devices affected by abnormal or undesired conditions
• CPC Class Codes: F16C 2202/30 Electric properties; Magnetic properties
• CPC Class Codes: F16C 33/586 outside the space between the races, e.g. end faces or bore of inner ring
• CPC Class Codes: G01L 5/0009 Force sensors associated with a bearing testing of bearings G01M13/04
• CPC Class Codes: G01P 3/443 mounted in bearings bearings F16C

Abstract

In a bearing unit (10), at least one sensor device (20, 21) is locked in a recess (16, 17) formed in a superficial zone of one of the races (11, 12). The stationary race (11) is partially covered with an electrically insulating material (30). An uncovered surface zone (32) is provided for electrically connecting the stationary race (11) to an electrical supply source located outside the bearing unit.

Claims

1. A bearing unit comprising;

a stationary race forming a raceway and being partially covered with an electrically insulating material,

a rotating race forming a raceway,

a plurality of rolling elements interposed between the races stationary and rotating raceways, and

at least one sensor device secured to one of the stationary race and the rotating race, and

an electrical connection for electrically connecting the stationary race to an electrical supply source located outside the bearing unit, and wherein

the electrical connection is a first electrical connection and the bearing unit further comprises a second electrical connection for electrically connecting the sensor device to one of the stationary race and the rotating race.

2. The bearing unit according to claim 1, wherein the sensor device is disposed in at least one recess formed in a peripheral area of at least one of the stationary race and the rotating race.

3. The bearing unit according to claim 2, wherein the sensor device is disposed in a recess formed in a peripheral area of the stationary outer race.

4. The bearing unit according to claim 2, wherein the sensor device is disposed in a recess formed in a peripheral area of the rotating race, the rotating race is electrically connected to the stationary race by at least one of the rolling elements and an electrically conductive grease contained in an annular gap defined between the stationary race and the rotating race, and the rotating race is partially coated with a layer of electrically insulating material.

5. The bearing unit according to claim 2, wherein the sensor device is embedded in a body made of one of resin material and plastic material, the body being located within the recess.

6. The bearing unit according to claim 1, further comprising a third electrical connection for electrically connecting the sensor device to a body or device outside the bearing unit.

7. The bearing unit according to claim 6, wherein the at least one sensor device includes two sensor devices, one of the two sensor devices being disposed in a recess of the stationary race and the other one of the two sensor devices is disposed in a recess of the rotating race, the stationary race and the rotating race are both partially coated with respective layers of electrically conductive material and each of the two sensor devices is connected to a separate second electrical connection for electrically connecting each sensor device to the one of the stationary and rotating races to which the sensor device is secured, and each of the two sensor devices is further connected to a separate third electrical connection for electrically connecting each sensor device to a body or device outside the bearing unit.

8. The bearing unit according to claim 7, wherein the recesses are formed in each race in peripheral areas distal from the raceways.

9. The bearing unit according to claim 6, wherein the first electrical connection and the third electrical connection are each located on cylindrical surfaces of the bearing unit coaxial with respect to a central axis of rotation of the bearing unit.

10. The bearing unit according to claim 1, wherein the at least one sensor device includes at least one of a temperature sensor, a vibration sensor, a load sensor, a load cell, a pressure transducer, and a magnetic rotation sensor.

11. The bearing unit according to claim 1, wherein the electrical connection includes a peripheral area of the stationary race uncovered by the electrically insulating material.

12. The bearing unit according to claim 11, wherein the uncovered area of the stationary race is a spot.

13. The bearing unit according to claim 11, wherein the uncovered area of the stationary race is shaped as a strip extending circumferentially along the stationary race.