Gas detection apparatus
US8293179B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 14, 2006 |
| Grant date | Oct 23, 2012 |
| Priority date | — |
| Expiry date | Feb 15, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/16
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A gas detection apparatus A comprises a signal processing circuit 20, a Wheatstone bridge circuit 21, integrating circuits 22 and 23, a differential amplification circuit 24, a direct current power supply circuit 25, a heater voltage application circuit 26. The Wheatstone bridge circuit 21 is configured of parallel combination of series circuits: one composed of a catalytic combustion type gas sensor 1 and a load resistor R1, and the other composed of a resistor R2, a variable resistor VR1 and a resistor R3. The heater voltage application circuit 26 is configured to generate a pulsed heater voltage by switching a direct current voltage of the direct current power supply circuit 25 through a transistor TR1 for applying the pulsed heater voltage to the Wheatstone bridge circuit 21. The integrating circuit 22 integrates a voltage at a connection point between the gas sensor 1 and the load resistor R1. The integrating circuit 23 integrates a voltage at a connection point between the variable resistor VR1 and the resistor R3. The differential amplification circuit 24 is configured to amplify a differential voltage between the output voltages of the integrating circuits 22 and 23. The si…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.