摘要 |
A trochoidal gear pump or engine uses a coaxial hub with the outer and/or inner rotor and an associated rolling element bearing assembly that preferably uses pre-loaded bearings to precisely set the rotational axis and/or the axial position of the rotor with which it is associated. This allows the fixed-gap clearance between the rotor surfaces and the housing surfaces or the other rotor surfaces to be set at a distance that minimizes operating fluid shear forces and/or by-pass leakage and eliminates gear tooth wear thus preserving effective chamber to chamber sealing. The device is useful in handling gaseous and two-phase fluids in expansion/contracting fluid engines/compressors and can incorporate an output shaft that accommodates an integrated condensate pump for use with Rankine cycles. A vent from the housing cavity to a lower pressure input or output port regulates built-up fluid pressure in the housing thereby optimizing the efficiency of the device by controlling bypass leakage. |