Phase sensitive coin discrimination method and apparatus
Coin checking device for a vending machine
Coin detection device
Valid coin acceptor for coin actuated apparatus
ApplicationNo. 804441 filed on 12/10/1991
US Classes:194/317, Having electric circuit influenced by check324/234Electrically energized nonforce type sensor
ExaminersPrimary: Bartuska, F. J.
Attorney, Agent or Firm
Foreign Patent References
International ClassG07D 005/08
AbstractApparatus for more accurately distinguishing between metal objects including coins based on the affect of the object or coin on the electrical characteristics of a pair of tank circuits when the tank circuits are subjected to a charging pulse which ends at a time when the object or coin is in the field thereof. The tank circuits can be connected into different configurations with the fields of their respective coils positioned to be subjected to the object or coin to be distinguished. The tank circuits can have similar or different characteristics and the coils of the tank circuits can be arranged in an aiding or in an opposing relationship. The present apparatus may also include apparatus to provide automatic tuning and self adjustment using a comparison between a portion of a signal produced by ringing one or more tank circuits and a fixed reference voltage level.