Gas sensor

Patent · Tue Mar 31 04:00:00 EST 1981

OSTI ID:6292483

Ohta, M; Segawa, Y; Yasuda, E

A gas sensor is described that includes a gas sensing element whose electrical resistance varies in accordance with the gas composition in the exhaust gas, especially the oxygen content in the exhaust gas, and a reference resistor connected in series with the gas sensing element. A predetermined voltage is applied across the series circuit of the gas sensing element and the reference resistor to detect the gas composition in the exhaust gas by a voltage at the junction point of the gas sensing element and the reference resistor. The gas sensor further comprises a circuit for monitoring the voltage at the junction point and another circuit responsive to the monitoring circuit to change the resistance of the reference resistor so that when the voltage at the junction point exceeds the predetermined range, the resistance of the reference resistor is changed such that the voltage at the junction point may change within the predetermined range in the state after the reference resistor is changed to ensure that the voltage at the junction point properly indicates the gas composition even if the resistance of the gas sensing element changes with the operating temperature of the gas sensing element or with time.

• Assignee: Nippon Soken Inc (Japan)
• Patent Number(s): US 4258563
• OSTI ID: 6292483
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330100* -- Internal Combustion Engines
330700 -- Advanced Propulsion Systems-- Emission Control
CONTROL SYSTEMS
DESIGN
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELEMENTS
ENGINES
EXHAUST GASES
FLUIDS
FUEL-AIR RATIO
GAS ANALYSIS
GASEOUS WASTES
GASES
HEAT ENGINES
INTERNAL COMBUSTION ENGINES
MEASURING INSTRUMENTS
METERS
NONMETALS
OXYGEN
OXYGEN METERS
PHYSICAL PROPERTIES
VOLTAGE DROP
WASTES