Bearing test apparatus for testing behavior of the bearing

Patent metadata

Field	Value
Publication number	US-10247638-B2
Application number	US-201715399073-A
Country	US
Kind code	B2
Filing date	Jan 5, 2017
Priority date	Nov 11, 2016
Publication date	Apr 2, 2019
Grant date	Apr 2, 2019

Abstract

A bearing test apparatus for testing a test bearing, including a chamber, a bearing cap disposed in the chamber and coupled to an outer wheel of the test bearing, a driving shaft connected to an inner wheel of the test bearing to rotate the inner wheel, an extension arm extending in a radial direction of the bearing cap from the bearing cap to expose one end thereof out of the chamber, and a measurement arm configured to make a contact with one end of the extension arm and configured to be rotatable by the extension arm. When a rotation force is applied to the bearing cap by the outer wheel, the extension arm is used to measure a force applied to the measurement arm, which is used to obtain an exclusive torque of the test bearing.

First claim

What is claimed is:

1. An apparatus for testing a test bearing, the apparatus comprising:
a chamber;
a bearing cap disposed in the chamber, and configured to be coupled to an outer wheel of the test bearing;
a driving shaft configured to be connected to an inner wheel of the test bearing;
an extension arm radially extending from the bearing cap, and protruding from the chamber;
a measurement arm contacting an end of the extension arm, and rotatable about an axis of the measurement arm; and
a force sensor coupled to the measurement arm.

2. The apparatus according to claim 1 , wherein the force sensor includes a load cell.

3. The apparatus according to claim 2 , further comprising:
a pre-load member configured to apply a force to the measurement arm at a location opposite to the load cell.

4. The apparatus according to claim 1 , wherein the driving shaft is further configured to rotate about an axis of the driving shaft that is parallel to the axis of the measurement arm.

5. The apparatus according to claim 1 , further comprising:
a radial rod configured to rotatably support the measurement arm, and push the extension arm to apply a radial load to the bearing cap.

6. The apparatus according to claim 1 , wherein either one of an end of the extension arm and an end of the measurement arm includes a spherical face.

7. The apparatus according to claim 1 , further comprising an optical displacement sensor, wherein
the test bearing includes a plurality of balls disposed between the outer wheel and the inner wheel, and a cage configured to fix locations of the plurality of balls,
the cage includes a reflecting surface protruding in an axial direction of the driving shaft,
the optical displacement sensor is configured to irradiate light toward the reflecting surface, and measure a distance from the cage to the reflecting surface.

8. The apparatus according to claim 1 , further comprising:
two optical displacement sensors disposed at an angle of 90 degrees with respect to each other, and inserted into the bearing cap.

9. The apparatus according to claim 1 , further comprising:
a cooling fluid tube formed through the bearing cap, configured to introduce a cooling fluid into a first inner space of the bearing cap, passing through a center of an upper end of the bearing cap, and configured to guide the cooling fluid to a center of an upper end of the test bearing.

10. The apparatus according to claim 9 , further comprising:
a flexible gasket surrounding the cooling fluid tube, and fixed to the bearing cap,
wherein the gasket is configured to be bent due to a difference between a pressure inside of the first inner space and a pressure outside of the first inner space, to seal a gap between the bearing cap and the cooling fluid tube.

11. The apparatus according to claim 10 , wherein
the cooling fluid tube includes an inner extension surrounded by the gasket, and an outer extension that is shorter than the inner extension and that extends toward an upper surface of the gasket, and
when the gasket is bent, the gasket makes a contact with an end of the outer extension.

12. The apparatus according to claim 11 ,
wherein the outer extension has a sharp end, and
wherein when the gasket is bent, the gasket makes a linear contact with the end of the outer extension.

13. The apparatus according to claim 12 , wherein the outer extension and the inner extension are spaced apart from each other to have a gap formed therebetween.

14. The apparatus according to claim 9 ,
wherein the cooling fluid tube is formed as an axial rod which presses against an upper end of the bearing cap to apply an axial load to the upper end of the bearing cap.

15. The apparatus according to claim 14 , wherein
the cooling fluid tube includes a large diameter portion pressing the upper end of the bearing cap, and a small diameter portion extending from the large diameter portion to pass through the bearing cap, and
the large diameter portion is connected to the bearing cap by connection bearing, and the small diameter portion and the bearing cap are spaced apart from each other so that the cooling fluid tube does not disturb rotation of the bearing cap.

16. The apparatus according to claim 9 ,
wherein a second inner space accommodating the bearing cap is formed at the chamber, and
wherein the cooling fluid flows from the first inner space to the second inner space via the test bearing.

17. The apparatus of claim 1 , wherein a torque of the test bearing is obtained by measuring a force applied by the extension arm to the measurement arm when a rotation force is applied by the outer wheel to the bearing cap.

18. The apparatus of claim 1 , further comprising a cooling fluid tube formed as an axial rod configured to apply a load to an end of the bearing cap.

19. The apparatus of claim 1 , further comprising a cooling fluid tube passing through a center of an upper end of the bearing cap.

20. The apparatus of claim 19 , wherein the cooling fluid tube is configured to introduce a cooling fluid into an inner space of the bearing cap.

21. The apparatus of claim 20 , wherein the cooling fluid tube is further configured to guide the cooling fluid to a center of an upper end of the test bearing.

22. The apparatus of claim 1 , where the axis is located between opposite ends of the measurement arm.

23. The apparatus of claim 1 , wherein the measurement arm comprises a bearing at the axis to enable the rotation.

24. A apparatus for testing a test bearing, which is a target for a test, the apparatus comprising:
a chamber;
a bearing cap disposed in the chamber, and coupled to an outer wheel of the test bearing;
a driving shaft connected to an inner wheel of the test bearing to rotate the inner wheel;
an extension arm extending in a radial direction of the bearing cap from the bearing cap to expose one end thereof out of the chamber; and
a measurement arm configured to make contact with one end of the extension arm, and configured to be rotatable by the extension arm,
wherein an exclusive torque of the test bearing is obtained by measuring a force applied to the measurement arm by the extension arm when a rotation force is applied to the bearing cap by the outer wheel,
wherein the bearing cap forms an inner space,
wherein the apparatus includes a cooling fluid tube formed through the bearing cap to introduce a cooling fluid into the inner space, and
wherein the cooling fluid tube extends to pass through a center of an upper end of the bearing cap, thereby guiding the cooling fluid to a center of an upper end of the test bearing.

Assignees

• Korea Inst Sci & Tech

Inventors

• Lee Yong Bok
• Choe Bok Seong
• Kwak Wonil
• Lee Jeon Kook
• Seo Ou Seok

Classifications

• F16C19/04

  for radial load mainly · CPC title

• G01D5/28

  with deflection of beams of light, e.g. for direct optical indication (G01D5/40 takes precedence; {mechanical adjustment G01D5/264}) · CPC title

• F16C2300/52

  low temperature, e.g. cryogenic temperature · CPC title

• G01M13/04 Primary

  Bearings · CPC title