Surface defect detecting apparatus for use with rotating circularly shaped metallic material
US4258319A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 5, 1978 |
| Grant date | Mar 24, 1981 |
| Priority date | — |
| Expiry date | Sep 5, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/9013
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The surface defect detecting apparatus for rotating cylindrical metal pieces which move in a lengthwise direction relative to a sensor block, has a plurality of eddy-current flaw detecting coils facing the test piece. The sensor block rotates about a horizontal axis extending vertically with respect to the axis of the test piece to follow up deflections of the test piece in the direction of the axis of rotation. Front and rear ends of the sensor block, have a pair of guide wheels that engage the piece; also present are color marking nozzles for marking defective areas in response to detector signals. Relative movement in the longitudinal direction of the test piece is carried out by means of a carriage carrying the sensor block. Each guide wheel is spaced from another in a plane transverse to the longitudinal direction of the test piece. A number of coils with designated impedances are connected to a generator and are disposed in longitudinal direction of the test piece in a single sensor holder within the sensor block. The holder has turning wheels at front and rear ends thereof in a longitudinal direction of the test piece, and are each positioned between the guide wheels in a di…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.