Patent · US Expired

Coin validating apparatus and method

US5526918A · kind A · utility

7Cited by
9References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 15, 1995
Grant dateJun 18, 1996
Priority date
Expiry dateJun 15, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG07D2205/001
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A coin validating system typically used in a coin operated machine electrically couples a stationary coin to the tuning coils of an oscillator circuit. While the coin is in a stationary position and the oscillator is tuned to a first rest frequency, the output frequency and output amplitude of the oscillator is measured. The metal coin will increase the signal frequency from its rest frequency and will decrease the signal amplitude from its rest amplitude. While the coin is stationary, frequency and amplitude are measured and compared with expected parameters of a valid coin. If a match is made, the rest frequency of the oscillator circuit is changed. At the second test frequency, signal frequency and amplitude are measured and compared with expected frequency and amplitude parameters for a valid coin. Only if a match is made at both the high frequency and the low frequency is an accept gate actuated.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.