Patent attributes
Disclosed is a thermal mass flowmeter, which comprises a heating unit disposed on an outer peripheral surface of a capillary tube, and a pair of temperature-sensing units each provided as a separate component from said heating unit. The temperature-sensing units are disposed on the outer peripheral surface of the capillary tube at respective positions equally distant from the heating unit toward an upstream side and a downstream side of the capillary tube. Each of the temperature-sensing units has a structure in which a temperature-sensing element is covered by a protective resin molded around the temperature-sensing element. The temperature-sensing element consists of a thermistor or a resistance temperature sensor. The temperature-sensing element is disposed to be displaced to a contact surface of the molded resin with the capillary tube relative to a center of the molded resin.