Coin detection means including a current ramp generator
US4809838A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 15, 1987 |
| Grant date | Mar 7, 1989 |
| Priority date | — |
| Expiry date | Jun 15, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07D5/02
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A coin detection system and method of operation thereof, comprising a sensing circuit portion including a sensor coil, which need be only a single sensor coil, positioned adjacent to the coin path and connected in circuit with a current ramp generator, preferably operable under control of a system control circuit portion, and a detector circuit portion connected to the sensing circuit portion to monitor and detect circuit performance characteristics and changes thereof that are effected by the presence of a coin within the field of the sensor coil at the time a current ramp is applied to the sensor coil by the ramp generator, from which circuit performance characteristics a coin characteristic value, preferably a time constant characteristic, representative of the particular coin present within the field of the sensor coil can be derived and thereafter utilized for coin detection, denomination discrimination, and coin sizing purposes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.