Thermal quantity meter for flowmeter in vehicle IC engine

The thermic quantity meter (1) consists of a cylindrical main channel (2, 3) within which is a shunt channel (16) incorporating a flow meter. This has conductor leads (35, 36) providing an electrical connection to the switching section (13) mounted on a rib (12) extending from the shunt channel. The connections t the supply voltage (28a-c) are also supported by the rib and attached to the reference potential side of the switching section. A rectangular plate (28d) extends across at least half of the base plate (25a) of the switching section housing (25). The conductor leads are fixed between the housing and the screening plate. This gives improved resistance to interference from electromagnetic waves. External electromagnetic noise and such like are drained off to earth.