Patent ID: 6769890
Filing Date: 2004-08-03
Classification: F04C,F05C

Abstract:
A gas rotary screw compressor comprising a casing having an intake conduit and a delivery conduit, said casing also having an inner surface and housing a male rotor with a longitudinal axis of symmetry and a female rotor with a longitudinal axis of symmetry, said male and female rotors having respective helical teeth;wherein the meshing line of said male rotor with said female rotor substantially lies in a central plane of said intake conduit, said plane passing through the center of said intake conduit and being simultaneously parallel to said axes; wherein at least one portion of the inner surface of the casing is shaped to follow the outer profile of said helical teeth so as to define a first intake chamber, to minimize, in said first intake chamber, the load losses of the gas as the gas flows towards said male and female rotors; and wherein said first intake chamber follows the helical shape of said male and female rotors up to an ideal compression plane inside said casing; the compressor being characterized by the fact that it also provides a second intake chamber which is located behind said first intake chamber with respect to said ideal compression plane in order to fill said casing with a maximum quantity of gas, and wherein, on the male rotor side, a point at which said first intake chamber intersects said ideal compression plane is separated by an angle &agr; from a cusp on said inner surface.