THERMAL AIR METER

摘要

A thermal airflow meter excellent in flow-rate measurement accuracy is provided. The airflow meter has a flow-rate measuring element comprising a heat resistor and a temperature-compensating resistor which are formed on the a first base member. A second base member of the airflow meter, provided with a drive circuit and a signal processor, is housed in a casing holding the flow-rate measuring element. The flow-rate measuring element is disposed in an air passage. Of two temperature sensors for measuring temperature at each of two points in the thermal airflow meter, respectively, a first temperature sensor is provided on the fist substrate of the flow-rate measuring element, and a second temperature sensor is provided inside the casing. The signal processor has a function of computing an airflow rate, an air temperature, and an air passage wall face temperature on the basis of an output signal of the flow-rate measuring element and respective output signals of the first and second sensors.