Abstract: A rotary device containing a housing having a curved inner surface with a profile equidistant from an trochoidal curve, an eccentric mounted on a shaft disposed within the housing, a rotor mounted on the eccentric shaft which contains at least three intersecting faces and a partial bore located at the intersection of adjacent faces, and at least three rollers rotatably mounted within the partial bores of the rotor.

Abstract: A method and apparatus for making a globoid screw for use as a mainrotor in a compressor or expander wherein a cylindrical rotor body is mounted for rotation about the longitudinal axis thereof, a cutter having a pluality of teeth at spaced locations around a circumference disposed in a plane and having an axis of rotation disposed perpendicular to that plane is mounted for rotation about its axis and is disposed so that the plane thereof is parallel to the rotor body longitudinal axis and so that the cutter rotational axis is perpendicular to the rotor longitudinal axis, and the rotor body and the cutter are rotated at synchronized speeds.