Force-sensing bearing

• US 7,316,168 B2
• Filed: 11/19/2003
• Issued: 01/08/2008
• Est. Priority Date: 11/23/2002
• Status: Expired due to Fees

• Current Assignee: INA-Schaeffler KG (INA-Holding Schaeffler GmbH & Co. KG)
• Original Assignee: FAG Kugelfischer AG (INA-Holding Schaeffler GmbH & Co. KG)
• Inventors: Hauser, Karin, van der Knokke, Henri, Wunderlich, Rainer, Hollweck, Roman
• Primary Examiner(s): Cygan; Michael
• Assistant Examiner(s): DUNLAP, JONATHAN M
• Application Number:
  US10/535,718
• Publication Number:
  US 20060070460A1
• Time in Patent Office: 1,511 Days
• Field of Search: 738/623.22, 738/623.81, 738/624.9, 738/625.41, 738/626.8, 738/626.2, 738/626.3
• US Class Current: 73/862.49
• CPC Class Codes: F16C 19/522 related to load on the bearing, e.g. bearings with load sensors or means to protect the bearing against overload
• 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 5/0019 by using strain gages, piezoelectric, piezo-resistive or other ohmic-resistance based sensors
• CPC Class Codes: G01M 13/04 Bearings

Abstract

The invention relates to a roller bearing comprising curved running paths, in addition to roller bodies and strain gauge sensors which are arranged between said running paths, said sensors being located in a groove on the outer diameter of the outer ring and/or on the inner diameter of the inner ring. The length of two adjacent strip conductor sections of the strain gauge sensor varies in such a way as to measure the angular position of the roller bodies between the strip conductors.

Claims

1. A rolling bearing comprising:

inner and outer rings having opposing, cooperating curved raceways and each ring having an inner and an outer diameter;

a plurality of rolling bodies arranged between the raceways for rolling along the raceways in a circumferential direction of the bearing rings and the rolling bodies also being movable in an axial direction of the bearing rings upon application of a force to the rings;

a plurality of strain gauge sensors arranged on at least one of the outer diameter of the outer ring and the inner diameter of the inner ring, wherein each of the strain gauge sensors comprises a plurality of circumferentially extending, conductor track sections arranged in a row of the sections in the axial direction of the bearing rings, and the lengths in the circumferential direction of two adjacent ones of the conductor track sections of the strain gauge sensor differ such that positions of the rolling bodies in the axial direction are detectable by the sensors.

2. The rolling bearing as claimed in claim 1, wherein the row of adjacent conductor track sections are so arranged with respect to each other and are of such lengths that together the sections define trapezoid in each of the plurality of sensors.

5. The rolling bearing as claimed in claim 1, further comprising a groove in the at least one of the outer diameter of the inner outer ring and the inner diameter of the inner ring and wherein the sensors are arranged in the groove.

3. A rolling bearing comprising:

inner and outer rings having curved raceways and each ring having an inner and an outer diameter;

a plurality of rolling bodies arranged between the raceways for rolling along the raceways in a circumferential direction of the bearing rings and the rolling bodies also being movable in an axial direction of the bearing rings upon application of a force to the rings;

a plurality of sensors arranged on at least one of the outer diameter of the outer ring and the inner diameter of the inner ring, wherein a distance in the circumferential direction between two circumferentially adjacent ones of the sensors on one of the rings varies in the axial direction such that positions of the rolling bodies in the axial direction are detectable by the sensors.

4. The rolling bearing as claimed in claim 3, further comprising a groove in the at least one of the outer diameter of the inner outer ring and the inner diameter of the inner ring and the sensors are arranged in the groove.

6. The rolling bearing as claimed in claim 3, wherein the sensors comprise conductor track sections extending in the circumferential direction, the track sections being arrayed in rows in the axial direction, and the distance between two circumferentially adjacent sections varies in axially adjacent rows of the track sections.

7. The rolling bearing as claimed in claim 3, wherein the sensors comprise conductor track sections having a length and being oriented to extend in both the axial and the circumferential directions and the conductor track sections also being oriented such that two of the conductor track sections are spaced apart a varying distance at selected different axial locations on the bearing.