US 12,189,077 B2
Metal detector
Yutaka Murata, Kitamoto (JP); Nobuyuki Kurosaki, Kitamoto (JP); Yuji Nishimura, Kitamoto (JP); Hisanobu Mizukawa, Kitamoto (JP); and Hiroaki Tsunemi, Kitamoto (JP)
Assigned to A&D Company, Limited, Tokyo (JP)
Appl. No. 17/776,882
Filed by A&D Company, Limited, Tokyo (JP)
PCT Filed Feb. 27, 2020, PCT No. PCT/JP2020/008059
§ 371(c)(1), (2) Date May 13, 2022,
PCT Pub. No. WO2021/100217, PCT Pub. Date May 27, 2021.
Claims priority of application No. 2019-209875 (JP), filed on Nov. 20, 2019.
Prior Publication US 2022/0342107 A1, Oct. 27, 2022
Int. Cl. G01V 3/08 (2006.01); G01V 3/10 (2006.01)
CPC G01V 3/083 (2013.01) [G01V 3/101 (2013.01); G01V 2003/086 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A device for detecting metal in an inspection region comprising
a magnetic field generation unit,
a magnetic field detection unit,
a control unit, and
a monitor,
wherein:
the magnetic field generation unit generates a magnetic field in the inspection region;
the magnetic field detection unit detects a magnetic field fluctuation in the inspection region;
the control unit comprises a transmission signal setting unit, a reception signal processing unit, a noise diagnosis unit, and a capacitor setting unit;
and wherein:
the control unit:
measures a change in the magnetic field in the inspection region while changing a frequency in a frequency range including the inspection frequency without fixing the frequency at the inspection frequency, and
displays a frequency distribution diagram obtained by performing frequency analysis of a measurement result on a monitor as a noise diagnosis result.