
The invention relates to a pressure valve with a flow passage (3) having a valve body (14) and a lifting plate (21) that has a surface area A.sub.2 transversally of the flow passage (3) that exceeds the cross sectional area A.sub.1 of the flow passage (3) at the valve seat (13) of the valve body, said pressure valve being configured such that, at any time, the container is in communication with the area above the lifting plate (21). The invention is characterised in that the pressure valve also ...











