Operating system for centrifuges

In a centrifugal rotor having an axially movable slide for opening and closing peripheral outlets from the separating chamber, there is formed a so-called closing chamber between the slide and the rotor body. The closing chamber is charged with operating liquid from the central axis of the rotor through a channel in the rotor. In the passage between the channel and the closing chamber are means by which the hydraulic pressure exerted on the slide from operating liquid in the channel is first reduced or eliminated in connection with discharge of operating liquid from the closing chamber and thereafter is again caused to act for closing of the slide.