Inductive coin sensor with position correction
US6739444B2 · kind B2 · utility
Inventors
Key dates
| Filing date | Feb 14, 2002 |
| Grant date | May 25, 2004 |
| Priority date | — |
| Expiry date | Jun 3, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07D5/08
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A coin sensor utilizes time-multiplexing of LC oscillators having natural frequencies F1A, F1B, F2, and F3 to produce magnetic fields in three sets of windings. As a coin passes through the coin sensor, the LC oscillators are separately enabled in a sequence to produce a frequency profile for each set of windings. A first winding produces a frequency profile for the facial area of a coin, a second winding produces a frequency profile for a cross-sectional area of a the coin, and a third winding produces a frequency profile for further distinguishing the relative size of a coin. A microcontroller identifies signature points from the frequency profiles and compares the signature points with stored signatures for a multitude of coins and/or tokens.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.