Trimode gas detection instrument
US4664886A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 13, 1983 |
| Grant date | May 12, 1987 |
| Priority date | — |
| Expiry date | Dec 13, 2003 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T436/207497
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A trimode gas detection instrument having three operating modes, one which monitors the level of combustible gases, a second which monitors oxygen, and a third which monitors the displacement of air by an unknown gas. Only two sensors are used, a combustible gas sensor and an oxygen sensor. A switch selects the input to a readout so that the user can quickly observe the concentration readings in any of the three modes. In the depletion mode the readout is calibrated in relation to the inverse of the normal concentration of oxygen in air--i.e., zero depletion corresponds to an oxygen concentration of 21%. In the event that an unknown gas displaces air in a sample atmosphere, concentration of the unknown gas appears on the readout, such that zero oxygen corresponds to a concentration of 100% unknown gas.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.