Direct drive refrigerant screw compressor with refrigerant lubricated rotors

Abstract

Disclosed is a direct-drive refrigerant screw compressor, having: a housing; a compression chamber in the housing; a pair of rotors, each rotor of the pair of rotors being rotationally disposed in the compression chamber and including an outer surface with a screw-geared profile; a fluid being disposed in the compression chamber, the fluid consisting of a working fluid for providing lubrication to each rotor; a first port extending through the housing and configured for directing the fluid toward the compression chamber; and when the compressor is activated, each rotor rotates and the fluid is distributed about each rotor to lubricate each rotor.

What is claimed is: 
     
         1 . A direct-drive refrigerant screw compressor, comprising:
 a housing;   a compression chamber in the housing;   a pair of rotors, each rotor of the pair of rotors being rotationally disposed in the compression chamber and including an outer surface with a screw-geared profile;   a fluid being disposed in the compression chamber, the fluid consisting of a working fluid for providing lubrication to each rotor;   a first port extending through the housing and configured for directing the fluid toward the compression chamber; and   when the compressor is activated, each rotor rotates and the fluid is distributed about each rotor to lubricate each rotor.   
     
     
         2 . The compressor of  claim 1 , wherein:
 the first port includes a flow control orifice.   
     
     
         3 . The compressor of  claim 1 , wherein:
 the first port extends directly into the compression chamber.   
     
     
         4 . The compressor of  claim 1 , wherein:
 the first port is fluidly connected to a passage in one rotor of the pair of rotors that directs the fluid to the compression chamber.   
     
     
         5 . The compressor of  claim 4 , wherein:
 the passage extends between an axial aft port in the one rotor and the outer surface of the one rotor.   
     
     
         6 . The compressor of  claim 5 , wherein:
 the passage includes an axial segment forming a blind hole and a radial segment fluidly connected between the axial segment and a surface port on the outer surface of the one rotor.   
     
     
         7 . The compressor of  claim 6 , wherein:
 the passage includes a plurality of the radial segments fluidly connected to a respective plurality of the surface ports on the outer surface of the one rotor.   
     
     
         8 . The compressor of  claim 7 , wherein:
 the plurality of the surface ports are staggered at regular intervals along the outer surface of the one rotor.   
     
     
         9 . The compressor of  claim 8 , wherein:
 the plurality of the radial segments each include opposing radial portions extending to a respective plurality of the surface ports on the outer surface of the one rotor.   
     
     
         10 . A refrigerant system including:
 a condenser;   the compressor of  claim 1 ; and   a conduit fluidly connecting the condenser and the first port of the compressor, and configured to transport the fluid to the compressor to provide the working fluid to each rotor.   
     
     
         11 . A method of directing fluid in a direct drive screw compressor, comprising:
 receiving fluid at a first port of a housing of the compressor, wherein the fluid consists of a working fluid for providing lubrication to each rotor of a pair of rotors in the compressor; and   directing the fluid from the first port to a compression chamber in the compressor; and   when the compressor is activated, each rotor rotates and the fluid is distributed about each rotor to lubricate each rotor.   
     
     
         12 . The method of  claim 11 , comprising:
 controlling flow through the first port with a flow control orifice.   
     
     
         13 . The method of  claim 11 , wherein:
 directing the fluid to the compression chamber includes:   injecting the fluid from the first port directly into the compression chamber.   
     
     
         14 . The method of  claim 11 , wherein:
 directing the fluid to the compression chamber includes:   injecting the fluid from the first port, through a passage in one rotor of the pair of rotors, whereby the fluid is injected into the compression chamber.   
     
     
         15 . The method of  claim 14 , wherein:
 injecting the fluid through the passage includes:   directing the fluid from the first port into an axial aft port in the passage and out an outer surface of the one rotor.   
     
     
         16 . The method of  claim 15 , wherein:
 directing the fluid through the passage further includes:   directing the fluid through an axial segment forming a blind hole in the one rotor and a radial segment fluidly connected between the axial segment and a first surface port on the outer surface of the one rotor.   
     
     
         17 . The method of  claim 16 , wherein:
 directing the fluid through the passage further includes:   directing the fluid though a plurality of the radial segments fluidly connected to a respective plurality of the surface ports on the outer surface of the one rotor.   
     
     
         18 . The method of  claim 17 , wherein:
 the plurality of surface ports are staggered at regular intervals along the outer surface of the one rotor.   
     
     
         19 . The method of  claim 18 , wherein:
 directing the fluid through the passage further includes:   directing the fluid through opposing radial portions of each of the plurality of the radial segments, the opposing radial portions extending to a respective plurality of the surface ports on the outer surface of the one rotor.   
     
     
         20 . The method of  claim 11 , comprising:
 receiving the fluid at the first port from a condenser in a refrigerant system in which the compressor is integrated, to provide the working fluid to each rotor.