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. 26, 1990
Filed:
Oct. 11, 1988
Paul K Griner, St. Louis, MO (US);
UniDynamics Corporation, New York, NY (US);
Abstract
Apparatus and method for evaluating a conductive coin to verify its authenticity and to determine its denomination. A first oscillator circuit generates a first oscillating signal for energizing a first coil producing a first magnetic field. The first oscillating signal has a first parameter which is a function of disturbances in the first magnetic field when the coin to be evaluated is located within the first magnetic field. A second oscillator circuit generates a second oscillating signal for energizing a second coil producing a second magnetic field. The second oscillating signal has a second parameter which is a function of disturbances in the second magnetic field when the coin to be evaluated is located within the second magnetic field. The parameters are converted to digital signals and provided to a computer which indicates the acceptability and denomination of the coin when a ratio or other arithmetic relationship of the first and second parameters is within an acceptable range.