Patent ID: 6119522
Filing Date: 2000-09-19
Classification: G01N

Abstract:
An electromagnetic acoustic transducer, comprising:a housing having a circular opening surrounding an exterior circumferential wall of a cylindrical object inserted into the housing;a plurality of magnets mounted in the housing and arranged around the circular opening at evenly spaced intervals, each magnet having an end adjacent the circular opening, the ends of adjacent magnets having opposite polarities;at least one electrically conductive wire coil mounted in the housing adjacent the ends of the plurality of magnets, wherein the at least one wire coil forms a cylindrical shape surrounding the circular opening;a signal generator connected to the at least one wire coil and supplying an electrical excitation signal to the at least one wire coil to induce vibrations in the cylindrical object; anda signal detector connected to the at least one wire coil and detecting an electrical response signal induced in the at least one wire coil by vibrations in the cylindrical object.