Method and apparatus for preventing damage by overheating to an air flow rate meter resistor

摘要

A method for preventing damage to a temperature-dependent resistor disposed in a flow cross section caused by overheating as a result of the ignition of a combustible, gaseous mixture during a burn-off procedure is proposed. A heating resistor is disposed in the flow cross section in the vicinity of the temperature-dependent resistor which is supplied with heating current by an electronic regulating circuit in such a manner that during the measuring operation the heating resistor has no current flowing through it, while immediately following the termination of the measuring operation but prior to the initiation of the burn-off procedure at the temperature-dependent resistor, the heating resistor experiences a flow of electric current through it, which heats it to an elevated temperature at which any combustible gases located in its vicinity ignite and burn.