Patent ID: 6450781
Filing Date: 2002-09-17
Classification: F04D,F25B

Abstract:
A centrifugal compressor assembly for use in a refrigerating system, the centrifugal compressor assembly comprising:two centrifugal compressor stages with rotors; diffuser ducts; a plurality of collection chambers; inlet and outlet tubing, wherein the outlet tubing of the first stage is connected to the inlet tubing of the second stage by a delivery duct; and a built-in electrical motor between the stages, the rotor of which is positioned with the compressor stage rotors on one shaft mounted on gasodynamic bearings, and the stator of which is fixed inside the motor housing, forming a cooling skirt between the stator and the motor housing, while inside the motor housing coolant feed and discharge ducts are connected to the compressor assembly's second stage outlet tubing; wherein the cooling skirt for the stator is formed by lengthwise slots on the surface of the stator in contact with the housing; and wherein a plurality of annular groves on the internal surface of the motor housing is connected to a second coolant feed duct and a second coolant discharge duct.