Patent · US Expired

Method of and apparatus for assessing coins

US4436196A · kind A · utility

16Cited by
8References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 18, 1981
Grant dateMar 13, 1984
Priority date
Expiry dateJun 18, 2001

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG07D5/08
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

The invention relates to a coin validator for use in a micro-processor controlled call coin box telephone instrument. The validator comprises first and second coil sets driven by square wave interrogation pulses. The arrangement of the coils is such that when a coin is in the coin-runway of the call coin box, one coil pair is used to interrogate the coin in the runway while the other coil pair provides environmental conditions apertaining to the runway. The information generated by both coil sets is combined thereby compensating for environmental changes and drift. Information pertaining to the relative response times of the secondary coils is then used to determine coin validity.

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