Admittance measuring system for monitoring the condition of materials
US4146834A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 22, 1976 |
| Grant date | Mar 27, 1979 |
| Priority date | — |
| Expiry date | Nov 22, 1996 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/028
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A two-wire transmitter includes an admittance sensing probe adapted to sense the conditions and corresponding admittance of materials. The probe is coupled into an admittance responsive network which generates an admittance signal representing the condition of materials. The output current from the transmitter is varied in response to the admittance signal. In one embodiment of the invention, the admittance responsive network comprises a variable frequency oscillator whose frequency varies with the admittance of the materials. In another embodiment, the admittance responsive network comprises a ramp generator with a frequency which varies with the admittance of the materials. In another embodiment, the admittance responsive network comprises a bridge whose balance changes in response to the admittance of the materials.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.