Fluid rotating apparatus with sealing arrangement

摘要

A fluid rotating apparatus includes a casing having a gas inhaling inlet and a gas discharge outlet, rotors driven in the casing by a driving mechanism and having fluid-transporting grooves which engage each other in synchronous rotation, and bearing portion for supporting the rotors. A communicating path is formed at one of the rotors and the and the casing for communicating a gas discharge-side inner space and a space defined by an inner surface of the casing and the fluid-transporting groove of an outer surface of each rotor with each other. The gas discharge-side inner space is defined by an end surface of the rotor opposite to a gas inhaling-side surface thereof, and a sealing portion which is formed between the rotor and the casing to prevent fluid from flowing into the gas discharge-side inner space.