Title:
METAL-DETECTION DEVICE
Document Type and Number:
WIPO Patent Application WO/2015/049766
Kind Code:
A1
Abstract:
[Problem] To provide a metal-detection device that can detect test materials including metallic foreign bodies with high precision using Lissajous waveforms. [Solution] In the present invention, a test material is moved to between a transmission coil and two reception coils, a coil signal is obtained that is the comparison value of the electrical power induced in the two reception coils, this coil signal is detected using two alternating-current signals with different phases, and a first detection signal and a second detection signal are obtained. When a normal test material (W) is moved, a reference Lissajous waveform (41) is obtained using the first detection signal and the second detection signal. A plurality of determination lines (51a, 51b, 51c, 51d) are set in regions that do not intersect or come into contact with the reference Lissajous waveform, and if a Lissajous waveform obtained during measurement intersects or comes into contact with any of the determination lines, the test material being measured is determined to be abnormal.
Inventors:
EDAMOTO MASAHIKO (JP)
Application Number:
PCT/JP2013/076985
Publication Date:
April 09, 2015
Filing Date:
October 03, 2013
Export Citation:
Assignee:
SYSTEM SQUARE INC (JP)
International Classes:
G01V3/10
Domestic Patent References:
| WO2004086095A1 | 2004-10-07 |
Foreign References:
| JP2007085873A | 2007-04-05 | |||
| JP2008058223A | 2008-03-13 |
Attorney, Agent or Firm:
NOZAKI, Teruo (JP)
Teruo Nozaki (JP)
Teruo Nozaki (JP)
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