High pressure single screw compressors

Abstract

A single screw mechanism of the positive displacement rotary type such as a ompressor or expander for varying the pressure of a fluid. A stationary housing having a bore symmetry surrounds and is configured to cooperate in a substantially fluid-tight manner with the surface of revolution of the crests of a compound conical mainrotor having a plurality of projecting spiral threads whose root width-thread height define substantially constant cross sectional chamber areas in the grooves between adjacent threads along their length for substantially fluid-tight engagement with the teeth of at least one rotatably mounted cylindrical gaterotor whose axis is symmetrically inclined at a transverse angle that is less than 90 degrees with respect to the fixed spin axis of said mainrotor so as to permit the toothed outer peripheral surface containing labyrinthial seals to extend through a window path opening in said housing thereby exposing one side of each gaterotor tooth face in meshing relation with the mainrotor chamber in the housing to the changed-pressure fluid during rotation. The housing is fitted with ports for the admission and discharge of fluid at opposite ends of said mainrotor, the ports for the passage of the changed-pressure fluid being axially aligned with the mainrotor and located in a discharge ring in close proximity whereat each gaterotor exits from engagement with the mainrotor. A hydrostatic type pressure port is provided in the housing on the suction side of the aforesaid window path.