The sensor device provides a signal representing the differential pressure acting on an air baffle plate using two sensors (7,8) contained in a common housing (2) respectively responsive to the difference pressure and to the barometric pressure. Pref. the housing is made of plastic.Two piezoresistive pressure sensors are mounted on opposite sides of a support plate (1) so that one lies in a chamber (18) subjected to the barometric air pressure and the other is acted on by an operating rod (13) displaced in dependence on the difference pressure.
