Coin discriminating apparatus

Abstract

A coin discriminating apparatus in which, to permit easy and reliable determination of the denomination and authenticity of a coin, information on surface displacement irregularities of a stamp pattern on a coin surface is detected, and features of the stamp pattern represented by the surface displacement irregularities information are plotted in the form of a histogram indicative of distribution of the surface displacement irregularities over the entire surface of the coin. The histogram is compared with a histogram of surface displacement irregularities distribution obtained beforehand with respect to a true coin to identify the denomination of the coin, thereby eliminating the need for a complicated process such as rotation of the stamp pattern (image information) on the coin surface. Preferably, eddy current induction coils are used to apply high-frequency electromagnetic field to a coin to induce eddy current therein, and impedances of the coils, that vary depending on the eddy current induced in the coin, are detected as the surface displacement irregularities information. Then, distribution of the detected impedances over the entire surface of the coin is obtained in the form of a histogram showing impedance along the abscissa and the numbers of eddy current induction coils with outputs in specified ranges along the ordinate. Also, based on the detected impedances, the material, diameter and thickness of the coin are determined for the coin discrimination.

Dependencies are inferred from the claim text.