The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 18, 1996
Filed:
Jun. 15, 1995
John Dullighan, Yardley, PA (US);
Ilia Kirshner, Glendale, NY (US);
Gerald Smith, Clayton, NJ (US);
John Wick, Parkesburg, PA (US);
Greenwald Industries Inc., Brooklyn, NY (US);
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.