| 摘要 |
A coin validator for discerning a thickness or a Pattern of a coin in a non-contact manner. When the coin passes through a coin path, a coin sensor senses the passage of the coin to cause a change in a resonant frequency of a resonator and hence to fluctuate a resonant output voltage. The thickness and pattern of the coin are detected in accordance with that fluctuation. The resonator has a variable capacitance diode added thereto as a resonant element. If the resonant frequency of the resonator deviates out of a reference resonant frequency range, a voltage corresponding to the deviation is applied across the variable capacitance diode to provide feedback control such that the resonant frequency returns within the reference resonant frequency range. |
