| 摘要 |
<p>A coin validator for discerning the thickness or pattern of a coin (1) in a non-contact manner. When the coin passes through a coin path, coin sensors (2, 3) sense the passage of the coin to cause a change in a resonant frequency of a resonator (7) and hence to fluctuate a resonant output voltage. The thickness and pattern of the coin (1) are detected in accordance with that fluctuation. The resonator (7) has a variable capacitance diode (13) added thereto as a resonant element. If the resonant frequency of the resonator (7) deviates out of a reference resonant frequency range, a voltage corresponding to the deviation is applied across the variable capacitance diode (13) to provide feedback control such that the resonant frequency returns within the reference resonant frequency range.</p> |
