DEVICE FOR MEASURING A FLOWING AIR VOLUME

摘要

A device for measuring a flowing air volume has a thick film sensor element exposed to the air flow and composed of a heating film resistance (RH) crossed by a current and of a sensor film resistance (RS) that is part of a bridge circuit and detects the temperature of the heating film resistance (RH), both resistances being arranged on an insulating substrate (10). The heating film resistance (RH) and the sensor film resistance (RS) are separated by an electrically insulating but thermally conductive intermediate layer (13) and housed in a bubble (11) made of ceramic material, in particular glass-ceramic, that forms an arch over the insulating substrate (10). The thin membrane (14) of ceramic material ensures an adequate thermal insulation between the film resistances (RH, RS) and the insulating substrate (10), making possible short response times.