Patent ID: 6769882
Filing Date: 2004-08-03
Classification: F04D

Abstract:
A pumping system of the type comprising a motor including a rotor within a fluid filled enclosure having hydrodynamic bearings supporting a drive shaft with an extended end engaging a regenerative turbine pump, the pump driving a thermal transfer fluid which also fills the enclosure and provides the lubricating fluid for the hydrodynamic bearings, comprising:a pump housing disposed about the extended end of the drive shaft and sealingly engaged to the rotor enclosure, the pump housing including a first interior narrow, circumferential chamber transverse to the drive shaft for receiving the regenerative turbine pump, and inlet and outlet ports in communication with opposite sides of the circumferential chamber adjacent its periphery; a second interior chamber within the pump housing and about the drive shaft on the side closest to the rotor, and a first pressure communication conduit extending between the output port and said second interior chamber; and at least one second pressure communicating conduit intercoupling the second interior chamber to the interior of the rotor enclosure.