Thermal mass flow sensor has heating element thermally connected to flow sensor tube, temp. sensors thermally connected to tube at heating element ends, heat-conducting earthing parts

摘要

The thermal mass flow sensor has a flow sensor tube (12) with an internal flow channel between input and output ends and a heating element (16) in thermally conducting connection with only part of the tube to heat the medium (28) flowing through it. Two temp. sensors (34) are thermally connected to the tube at the ends of the heating element and two thermally conducting earthing parts are used to produce inlet and outlet reference signals.