Title:
COIN DETECTOR
Document Type and Number:
WIPO Patent Application WO/2001/029785
Kind Code:
A1
Abstract:
High-frequency electromagnetic fields are applied to a coin (10) using eddy-current coils (2), and the changes in impedance of the eddy-current coils due to the influence of eddy currents induced in the coin by the high-frequency fields is measured to obtain information about raised marks on coin faces. Low-frequency electromagnetic fields are applied to a coin (10) using eddy-current coils, and the changes in impedance of the eddy-current coils due to the influence of eddy currents induced in the coin by the low-frequency fields is measured to obtain information about the materials of the coin. Such information (impedance of eddy-current coils) is utilized to accurately determine the kind of coin and check for forgery.
Inventors:
HOUSE LARRY J
DAVIS RICHARD J
DAVIS RICHARD J
Application Number:
PCT/JP2000/002109
Publication Date:
April 26, 2001
Filing Date:
March 31, 2000
Export Citation:
Assignee:
JAPAN TOBACCO INC (JP)
International Classes:
G07D5/00; G07D5/08; G07D5/02; (IPC1-7): G07D5/08
Foreign References:
| JPH11250305A | 1999-09-17 | |||
| JPH11175793A | 1999-07-02 | |||
| JPH10162189A | 1998-06-19 |
Attorney, Agent or Firm:
Nagato, Kanji (Shinbashi 5-chome Minato-ku, Tokyo, JP)
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