Gas monitoring apparatus
US5198774A · kind A · utility
Inventors
Key dates
| Filing date | Mar 19, 1990 |
| Grant date | Mar 30, 1993 |
| Priority date | — |
| Expiry date | Mar 19, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/70
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
There is disclosed apparatus for monitoring the concentration levels of halogen gas in a gaseous atmosphere as confined in an enclosure over a relatively extended period of time. Such monitoring apparatus includes a sensor including first and second electrodes disposed to define a space therebetween through which the gaseous atmosphere flows and a voltage source for applying a voltage between the first and second electrodes whereby an ionization current flows to the first electrode. A control mechanism illustratively in the form of a programmed microcontroller monitors the ionization current collected by the first electrode as the output signal of the sensor, to determine an increase therein as would be indicative of a halogen leak. Upon determining an increase of the sensor output signal above a predetermined difference, the control mechanism removes the energization from the halogen sensor whereby the ionization current is terminated and the life of the sensor extended. The control mechanism further causes an initial reading of the sensor signal to be taken and to be stored, whereby subsequent sensor readings may be compensated by subtracting the stored value therefrom to provide…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.