Non-contacting inductively coupled displacement sensor system for detecting levels of conductive, non-magnetic liquids, and method of detecting levels of such liquids
US4912407A · kind A · utility
16Cited by
12References
6Claims
0Family size
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Key dates
| Filing date | Nov 23, 1988 |
| Grant date | Mar 27, 1990 |
| Priority date | — |
| Expiry date | Nov 23, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S73/05
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An inductance coil serves as a displacement sensor arranged in connection with a tuned circuit of an oscillator. Liquid level displacement in an LEC crystal growth environment is sensed as a frequency change in the oscillator circuit as compared to a set point value. The sensor is protected from the environment by an outer protective sheath of non-conductive, non-contaminating material such as boron nitride.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.