Patent · US Expired

Edge detection and seam tracking with EMATs

US6155117A · kind A · utility

218Cited by
4References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 18, 1999
Grant dateDec 5, 2000
Priority date
Expiry dateMar 18, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N2291/102
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method for detecting the location of an edge, interface, seam or other structure of a workpiece uses one or two electromagnetic acoustic transducers (EMATs) to transmit an ultrasonic wave along the workpiece toward the edge and to receive a reflected wave. The velocity of the wave in the material is used in conjunction with the round trip time-of-flight (TOF) of the transmitted and reflected wave, to calculate the location of the edge. This is done by placing the transducer or transducers at known locations on the workpiece. A surface wave or 90 degree shear wave can be utilized and no contact is needed between the transducer and the surface of the workpiece. Rough and/or dirty surfaces and hostile environments can be accommodated while practicing the invention.

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