Air flowmeter

Abstract

Abstract PURPOSE:To enhance the durability of a hot-wire type sensor and to prevent the compositional change of the hot-wire resistor of the sensor, by heating the surface of the hot-wire type sensor by the heat generator provided in the vicinity of the hot-wire type sensor of an air flowmeter to burn up the adhered substance accumulated on said surface. CONSTITUTION:A hot-wire type air flow rate sensor 7 and a temp. compensation sensor 8 are arranged to the body 2 of an air flowmeter 1 and a heat generator 9 is arranged in the vicinity of the sensors 7, 8. When the adhered substance such as carbon adhered to the sensors 7, 8 are burnt up, the heat generator 9 is energized to be heated and this heat is transmitted to the sensors 7, 8 which are, in turn, gradually heated to burn up the adhered substance. As mentioned above, since the sensors 7, 8 are gradually heated from the surfaces thereof, the mechanical fatigue of the hot-air resistors constituting the sensors 7, 8 and the connection part of said resistors and the support member thereof does not become too much and the durability thereof is enhanced. Further, the change in the resistance values of the hot-wire resistors due to the compositional change therein is reduced.

Inventors

• 👤 Hirotaka Kumada
• 👤 熊田　博孝

Bibliographic Details