Patent ID: 7823398

Claim:
A rotating vane machine operating on a refrigeration, air-conditioning, or heat-pump cycle, wherein compression occurs within a compressor casing containing a cylindrical compressor rotor, and expansion occurs first in a valve or control device and thereafter within an expander casing containing a cylindrical expander rotor, said compressor and expander casings being located axially relative to each other, said rotors having flat end faces and being keyed to a common shaft, said compressor casing and expander casing being separated by a plate containing a seal riding on said shaft that inhibits leakage from said compressor casing to said expander casing and also in the reverse direction, the shaft being configured with a stepped up and stepped down portion between said compressor and said expander rotors, the seal is riding on the stepped down portion, the separating plate is configured in such a way that the plate is closely fitting on the seal and the stepped down portion of the shaft between the compressor and the expander rotors, said compressor rotor being driven by an external power source and said expander rotor returning expansion energy of the refrigerant to said shaft to reduce required input power, said shaft being supported in bearings, said rotors containing radial slots containing substantially rectangular vanes which have a close fitting arrangement with said casings and plate surfaces that abut said flat rotor faces, said rotors being eccentrically located within said casing components such that an exceedingly close but non-touching relationship exists between said rotors and casing components at their minimum clearance, said vanes having axial lengths and number of vanes to ensure the required volume ratios are achieved for said refrigeration, air-conditioning, or heat-pump cycle, said shaft containing two shoulders which together with two thrust bearings limit axial movement of said compressor and expander rotors to avoid rubbing friction against adjacent flat faces of said compressor and expander casings and separating flat plate, yet maintain fine clearances.