The proposal is for a blade cell compressor designed to compress a medium. The blade cell compressor comprises a cylindrical chamber arranged in a part of a casing in which runs a cylindrical rotor which is in (almost) sealing contact with the chamber wall along at least one generatrix and has radial longitudinal grooves in which blades are guided which divide the working space between the surface of the rotor and the chamber wall into cells, and with a lubricant tank which is under intake pressure during the operation of the blade cell compressor and which is linked via a supply line passing through the rotor to at least one lubricating groove arranged in at least one of the two facing surfaces of the rotor and a cover plate covering the chamber in the housing. In order to stop the flow of lubricant from its high to the low-pressure side owing to the overpressure still prevailing in the lubricant tank after the blade cell compressor has been shut down, a valve acting against the direction of supply is arranged in the supply line which opens when the rotor is running and closes when it is stopped.
