THERMAL MASS FLOW SENSOR

摘要

A thermal mass flow sensor is disclosed that includes a housing (16) having a first sensor region and a second sensor region, a first thin film temperature sensor (39) formed at the first sensor region and a second thin film temperature sensor (58) formed at the second sensor region. A heating element (40) is arranged to heat the first temperature sensor (39) and a controller (46) is operably connected to the first temperature sensor (39), the second temperature sensor (58) and the heating element (40), and controls a power level to the heating element (40) to maintaining a temperature difference between the first temperature sensor (39) and the second temperature sensor (58). Said first temperature sensor is mounted at an angle of preferably 12 to 70 degrees to said second temperature sensor and f preferably 6 to 35 degrees to the flow direction. A thin film temperature sensor and a method of using the thermal mass flow sensor are also disclosed.