Ventilation valve, especially for small pressure differences

摘要

The valve has a housing (11) with a valve chamber (12) in communication with an inlet (16) and an outlet (17) and a valve body (24) operating in the valve chamber. The valve body moves between a closed position upstream of the fluid and at least one open position upstream of the fluid. The valve body is formed as a fluid-tight hollow body (25). At least part of the valve body wall is rubber-like and deformable. An inner chamber (46) of the valve body is connected with at least one control opening (47) to supply or receive a control fluid, to control fluid overflow between the inlet and the outlet by changing the volume of the hollow body.