Proximity detector using inductive effect on oscillating circuit the charge of which is controlled by a pulse of short duration
US4893076A · kind A · utility
10Cited by
5References
5Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 22, 1988 |
| Grant date | Jan 9, 1990 |
| Priority date | — |
| Expiry date | Apr 22, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/9537
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A proximity detector is provided with an oscillating circuit generating cyclically an unsustained pseudo-oscillation. The detector includes a processing circuit having a comparator which compares the relaxation voltage of the oscillating circuit with a predetermined threshold and a logic circuit which generates control pulses with low duty ratio for a switch in series with the oscillating circuit and also an output signal as a function of the measurement pulses delivered by the comparator. The closure duration of the switch is substantially equal to half the pseudo-oscillation period.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.