Gas detector and its adjusting method
US6055849A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 1, 1998 |
| Grant date | May 2, 2000 |
| Priority date | — |
| Expiry date | Sep 1, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/122
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A metal oxide semiconductor gas sensor S is connected to a ladder resistance R, and the output voltage is subjected to logarithmic transformation at plural points on a waveform of temperature change by EQU LnR=2-4 V R1/Vc+LnR1 (1) where R indicating the resistance of the metal oxide semiconductor, V R1 the output voltage to the ladder resistance, Vc the detecting voltage, R1 the resistance of the ladder resistance, and Ln natural logarithm, respectively. Standard signals comprising logarithms of resistance values of the metal oxide semiconductor in plural concentrations and at plural points on the waveform are stored in the EEPROM, and these standard signals and logarithms obtained are compared with each other to detect the gas.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.