PURPOSE: To increase variation in output voltage with a flow rate by providing the 1st control part which has a temperature detecting element and a heater for temperature control at the upstream side in a flow passage and also arranging the 2nd control part which has a temperature detecting element, heater for temperature control, and heater for preheating at the downstream side.
CONSTITUTION: For example, when the intake air flow of an engine is measured, the output voltage variation with the flow rate is increased to obtain excellent responsiveness. For the purpose, a sensor part 11 installed in the intake air pipe of the engine is provided with the 1st control part 31 provided with a diode 41 as the temperature detecting element and the heater 42 for temperature control and the 2nd control part 32 provided with a diode 44 as the temperature detecting element, heater 43 for temperature control, and heater 45 for preheating so that the 1st and the 2nd control parts are at different height. The heater 45 for preheating is controlled by a constant power consumption circuit to obtain such excellent responsiveness that the voltage of the heater 43 for temperature control of the 2nd control part 32 varies greatly with the intake air flow.
HATSUTORI TADASHI
IWASAKI YUKIO
KOHAMA TOKIO
KANEHARA KENJI
