Rotary positive displacement machine for incompressible media

A positive displacement machine for incompressible media, comprising:

• a stationary housing;
• a working chamber having inner and outer circumferential walls separated by a bottom surface, an inlet and an outlet, said working chamber being located in the stationary housing and having the configuration of a circular slot;
• a land extending from said housing into the working chamber;
• said inlet being separated from said outlet by said land;
• a disk shaped rotor located within said housing and driven eccentrically relative to the housing;
• a circular displacer body located in said working chamber and being held on said disk shaped rotor so as to be driven eccentrically relative to the housing in a manner such that in operation the circular displacer carries out a circular motion limited by the circumferential walls of the working chamber;
• the curvature of said displacer is dimensioned relative to the curvature of the working chamber so that the displacer contacts the inner and outer circumferential walls of the working chamber at a sealing line continuously progressing in operation, thereby dividing the working chamber into inner and outer work spaces, by which work spaces the medium is conveyed from the inlet to the outlet;
• said displacer body being interrupted in the area of said land;
• a coupling is provided for interconnecting the displacer body relative to the housing;
• a wobble rod connected to said displacer body and a driving crank connected to said wobble rod wherein said wobble rod as driven by said driving crank provides for the circular motion of the displacer body;
• in the area of the land, the inner and outer work spaces communicate with each other at the inlet and the outlet;
• the displacer body and the working chamber have an at least approximately circular configuration over the overwhelming part of their configuration;
• the displacer body being arranged so as to seal over at least 360.degree.;
• wherein an end of said displacer body on an inlet side of the displacer body and the working chamber and an end of the displacer body on an outlet side of the displacer body and the working chamber, in an angular zone .alpha. of maximum 30.degree., each have significantly smaller radii of curvature than that of the overwhelming circumference.