High output capacitative gas/liquid detector
US6212956A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 23, 1998 |
| Grant date | Apr 10, 2001 |
| Priority date | — |
| Expiry date | Dec 23, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/221
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A gas or liquid detector that includes a capacitative sensor and a capacitance detector. The capacitative sensor includes a first electrode and a second electrode separated from one another, and additionally includes Debye elements extant in the liquid adjacent such portions of the electrodes that are in contact with the liquid. The Debye elements each include a Debye capacitor with an associated shunt conductor. The shunt conductor has an exponentially-increasing conductance versus voltage characteristic. The Debye element adjacent the first electrode and the Debye element adjacent the second electrode are connected in series by conduction through the liquid. The Debye element adjacent at least the first electrode has a substantially greater capacitance than the capacitance between the electrodes absent the Debye elements. The capacitance detector is connected to the capacitative sensor and measures the capacitance of the capacitative sensor by applying an alternating voltage between the electrodes. The alternating voltage has a voltage amplitude less than the voltage amplitude at which the Debye element extant adjacent at least the first electrode ceases to be predominantly capac…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.