Klappe

摘要

The doser consists of a body (1) traversed by a duct (2) containing a throttling disc (3) controlled by a drive (11). One edge of the disc pivots against a projection (4) on the wall of the duct, while its other edge is connected to a rod (8) which slides in an aperture (7), rotating the disc as the rod moves axially by means of a spiral mechanism (9,10) comprising a lug and a helical groove. The pivoted edge of the disc has a hemispherical recess (6) in it which interacts with the projection on the wall of the duct. The disc drive is in the form of a spring-loaded piston and a membrane (13), with the piston's movement away from the disc controlled by an adjustable stop (25) which is preferably adjustable.