Two parallel bearing-supported, inter meshing screw rotors having opposite threads synchronously and contactlessly counter-rotate in a cylindrical housing that tightly encloses them, and together form a multi-stage pump.
Because of the counter-mesh of the two rotors, the volumes sealed in each thread are advanced along the rotors to the outlet. The pump has no valves at either inlet or outlet. When a displacement volume reaches the outlet opening, the pressure is equalized with the atmosphere.
This means that atmospheric air flows into the displacement volume and is then discharged again as the rotor turns.
Because of the counter-mesh of the two rotors, the volumes sealed in each thread are advanced along the rotors to the outlet. The pump has no valves at either inlet or outlet. When a displacement volume reaches the outlet opening, the pressure is equalized with the atmosphere.
This means that atmospheric air flows into the displacement volume and is then discharged again as the rotor turns.