Patent · US Expired

Coin detection device

US4805754A · kind A · utility

7Cited by
3References
12Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 30, 1986
Grant dateFeb 21, 1989
Priority date
Expiry dateDec 30, 2006

Classification

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

Abstract

A coin detecting device suitable for use in conjunction with a coin acceptor of a type employed in a gaming or vending machine comprises an inclined channel-shaped track which is formed from an insulating material and along which a coin may roll. Three flat metal plates are located on one side wall of the track, the plates being spaced apart in the direction of movement of the coin down the track and being separated from the coin by the (insulating material) wall of the track. The plates are spaced apart by a distance such that the coin will initially overlap first and second ones of the plates to form a first pair of series capacitors and, thereafter, will overlap the second and third plates to form a second pair of series capacitors. Voltage pulses are applied to the second (intermediate) plate and a detector circuit is connected in circuit with the first and third plates. The detector circuit is arranged to provide an output signal which is indicative of a predetermined increase in the capacitance of the circuits which incorporate the first and second pairs of capacitors responsive to movement of the coin past the pairs of plates.

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