Patent · US Expired

Electronically scanned eddy current flaw inspection

US4785243A · kind A · utility

21Cited by
15References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 29, 1987
Grant dateNov 15, 1988
Priority date
Expiry dateJan 29, 2007

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N27/9013
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Method and apparatus for performing eddy current flaw inspection on workpiece material such as steel bar stock. A drive mechanism propels a workpiece longitudinally along a workpiece path. An array of electromagnetic transmitter coils is disposed about the workpiece path. An electromagnetic source energizes the transmitter coils under control of multiplexing circuitry. The multiplexing circuitry and source actuate respective transmitter coils in a predetermined iterative sequence. The sequential actuation induces eddy currents in the workpiece at a succession of locations extending iteratively about the workpiece circumference. Circuitry coupled to multiple, differentially wound sensing coils detects variations in eddy current produced in the workpiece and utilizes these detected variations to produce flaw indicating signals.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.