Planar coil apparatus for providing a frequency output vs. position
US4658153A · kind A · utility
Inventors
Key dates
| Filing date | May 12, 1986 |
| Grant date | Apr 14, 1987 |
| Priority date | — |
| Expiry date | May 12, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B7/023
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The position sensor constitutes a fixed planar board having disposed on the surface serpentine coil structures of relatively low resistance and inductance. The coils are driven in a resonance mode which provides a frequency output according to the position of a moving planar member. The second movable planar board has disposed on the surface thereof planar loop coil structures. The second board is moved in proximity to the first board to vary the resonance characteristics of the first coil according to the position of the second board with respect to the fixed board. In this manner the frequency output of the system is a function of the position of the boards with respect to one another. Other embodiments depict means for compensating the thermal drifts of the frequency with respect to temperature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.