公开(公告)号：US11762118B2

公开(公告)日：2023-09-19

申请号：US17597058

申请日：2020-05-19

Applicant: ANRITSU CORPORATION

Inventor： Eiji Taniguchi ,  Chie Nishimura ,  Yuki Hayakawa

IPC: G01V3/10 ,  G01R33/10 ,  G01V3/08 ,  G01V3/38 ,  G01N27/72

CPC classification number: G01V3/10 ,  G01N27/72 ,  G01R33/10 ,  G01V3/081 ,  G01V3/38

Abstract: A metal detection apparatus that can accurately and automatically determine whether a metal passing through the inspection area is a magnetic or non-magnetic metal comprises a detection unit quadrature-detecting a differential detection signal of magnetic field fluctuation in the inspection area due to the passage of a workpiece, and a determination unit that determines the presence or absence of a mixed metal based on both fluctuation components after the detection. The determination unit compares sample signal phase data obtained beforehand from the detection signal of the magnetic field fluctuation in the inspection area due to the passage of various metal samples, with the signal phase data obtained from the detection signal of the magnetic field fluctuation in the inspection area due to the passage of the workpiece mixed with metal, and determines the type of metal passing through the inspection area based on the phase determination result.