Auxiliary valve for a servo-controlled vacuum-control valve, especially for milking systems

摘要

The subject-matter of the present invention is the special design of the auxiliary valve which is an essential control element of a device for controlling the reduced pressure in a reduced-pressure-line system. In the previously known control devices having a corresponding auxiliary valve, said valve is designed such that a metal piece in the shape of a spherical segment is provided on a metal valve seat which is countersunk in an only slightly spherical manner, as a result of which, because of unavoidable production inaccuracies, there is a severe inclination for pressure fluctuations to occur in the reduced-pressure-line system. In contrast to the known designs, the present invention provides a flat-seating valve in which an intermediate ring consisting of soft rubber or a similar sealing material is used. Undamped pressure fluctuations in the reduced-pressure-line system are in this way reliably prevented, even in the case of certain production inaccuracies.