| 摘要 |
PROBLEM TO BE SOLVED: To provide an apparatus capable of performing coin detection of high reliability without being affected by dust or dirt in air even when a coin tray is in such a shape that it is hard to take change out, and also relatively long in distance to a coin which is made of nonmagnetic metal.SOLUTION: A remaining coin detection sensor 12 is arranged below a bottom surface part 14 of a coin tray 10, and an electromagnetic wave of high frequency is normally emitted from an oscillation coil 32 of an LC oscillation circuit toward the tray bottom surface part. A microcomputer measures an oscillation frequency of the LC oscillation circuit successively, and the measured oscillation frequency is compared with a reference frequency stored in a memory so as to determine whether an oscillation frequency increasing when coins C1, C2 are present in a coin tray becomes a programmed value higher than the reference frequency, thereby outputting a coin residue signal when the oscillation frequency becomes the set value higher than the reference frequency.SELECTED DRAWING: Figure 2 |
