Non-contact proximity switch
US4771359A · kind A · utility
Inventor
Key dates
| Filing date | Dec 24, 1986 |
| Grant date | Sep 13, 1988 |
| Priority date | — |
| Expiry date | Dec 24, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/9537
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A non-contact proximity switch with an oscillation circuit (L 1, C 1) which is activated in a step-like manner, has a reference voltage source (6) which produces at least one reference voltage level (U.sub.ref) and has at least one comparator (5) which compares the amplitude of the transient response with the associated reference voltage level (U.sub.ref) in order to be able to detect at least one value that is distinctive for the time curve of the decaying oscillation from at least one transient response of the oscillation circuit (L 1, C 1) after such an activation. At least one counter (7, 10) counts, at least within a portion of the decay period of the transient response, the number (DA) of the half-waves of the transient response, the peak of which deviated from the associated reference voltage level (U.sub.ref) in one of the two directions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.