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FIXTURE FOR INSPECTION OF ROLLING ELEMENT BEARINGS

IP.com Disclosure Number: IPCOM000247371D
Publication Date: 2016-Aug-29
Document File: 6 page(s) / 151K

Publishing Venue

The IP.com Prior Art Database

Abstract

A fixture is provided for methodically inspecting a rolling element of a bearing, such as a bearing ball. The fixture has a mechanism to produce controlled rotation of the ball about two mutually perpendicular axes.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 39% of the total text.

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FIXTURE FOR INSPECTION OF ROLLING ELEMENT BEARINGS

ABSTRACT


[0001] A fixture is provided for methodically inspecting a rolling element of a bearing, such as a bearing ball. The fixture has a mechanism to produce controlled rotation of the ball about two mutually perpendicular axes.

BACKGROUND


[0002] This disclosure relates generally to inspection methods and more particularly to methods for inspecting rolling element bearings.


[0003] Rolling element bearings such as those used in gas turbine engines incorporate rollers or balls. Rolling elements may be made from materials such as metal alloys or ceramics such as silicon nitride (SiN4). In order to meet applicable quality control requirements, the balls must be free of surface defects such as cracks.


[0004] One common method used to inspect bearing balls for surface defects is dye penetrant inspection, more particularly fluorescent dye penetrant inspection. In this process, the bearing ball is cleaned and then treated with a penetrant. The penetrant infiltrates cracks or other small defects and makes them visible under UV illumination. The ball is then visually inspected, for example using a microscope.


[0005] Currently this process is inconsistent, as the ball is placed into a holder and then manually rotated to expose its surface to the field of view of the microscope. The balls have a smooth, highly-polished surface finish and cannot be marked to indicate their orientation. It is thus difficult for inspector to ensure that 100% of the surface has been observed. Furthermore, it often requires excessive manipulation to guarantee 100% surface coverage.


[0006] Described herein is a fixture usable to ensure consistent complete coverage of the

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surface of the bearing ball with a minimal amount of manipulation.

BRIEF DESCRIPTION OF THE DRAWINGS


[0007] The concept may be best understood by reference to the following description taken in conjunction with the accompanying drawing figures, in which:


[0008] FIG. 1 is a schematic top plan view of a bearing inspection fixture;


[0009] FIG. 2 is a partially-sectioned view of the bearing inspection fixture shown in FIG. 1;


[0010] FIG. 3 is a front elevation view of the bearing inspection fixture of FIG. 1;


[0011] FIG. 4 is a schematic view showing a ball mounted for inspection in the fixture of FIG. 1, with the ball oriented in a first position; and


[0012] FIG. 5 is a schematic view showing a ball mounted for inspection in the fixture of FIG. 1, with the ball oriented in a second position.

DETAILED DESCRIPTION OF THE CONCEPT


[0013] Illustrated in FIGS. 1-3 is a schematic representation of a fixture 10 suitable for use for visual inspection of a rolling bearing element such as a bearing ball "B". The fixture 10 includes a housing 12 with an upper surface 14 that defines a nest 16 to receive the ball B and position it with its upper half exposed. The nest 16 may be defined by an insert 18 of a low-friction material such as polyt...