| 摘要 |
A coin presence sensing apparatus comprises one or more ringing electronic oscillator circuits at least some of which include an inductor having a dumbbell shaped core adjacent a coin passageway. A pulse generating circuit is provided to selectively pulse each oscillator circuit. After the oscillator is pulsed, it begins to oscillate. Coin proximity during the time the oscillating circuit oscillates is determined by comparing the output of the oscillating circuit with the output of an oscillating circuit having a reference inductor isolated from coins. |
