Device for coin checking
US4742903A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 19, 1986 |
| Grant date | May 10, 1988 |
| Priority date | — |
| Expiry date | Jun 19, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07D5/08
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
The coin to be checked for several characteristics influences, partially in succession and partially simultaneously, the coils (7-12) of several oscillator tank circuits (1-6). The oscillator tank circuits (1-6) are correspondingly connected to an amplifier (14) for the formation of an oscillator, individually in succession, those circuits with simultaneously influenced coils being connected periodically in alternation to this amplifier. Thereby, successive and simultaneous, high-frequency test signals are produced which are nested in one another in accordance with the time-division multiplex principle, these test signals corresponding to the influences exerted by the coin on the oscillator tank circuit coils (7-12). These test signals, after demodulation (19) and analog-to-digital conversion (20), are compared in an evaluating unit (22) individually with criteria stored in a memory (23) for each type of coin to be accepted.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.