Patent ID: 11898561
Assignee: CARRIER CORPORATION
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F | IPC F

Claim 3:
4. 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 disposed in a compression chamber defined in the housing, the pair of rotors including a first rotor and a second rotor, each rotor including an outer surface with a screw-geared profile to define alternating peaks and troughs axially along the outer surface, wherein the working fluid is refrigerant, the second rotor having respective first and second axial shaft portions, the first axial shaft portion being driven by a motor disposed in the housing; and
directing the working fluid from the first port through the second axial shaft portion and the second rotor to the compression chamber,
wherein:
when the compressor is activated, each rotor rotates and the working fluid is distributed about each rotor to lubricate each rotor; and
for each rotor, a plurality of bearing packs is disposed within a respective plurality of bearing chambers in the housing, and

wherein the method further includes:
the directing the working fluid from the first port to the compression chamber further includes injecting the working fluid from the first port through a passage only formed in the second rotor of the pair of rotors so that working fluid is injected into the compression chamber from the second rotor;
the injecting the working fluid through the passage further includes directing the working fluid from the first port into an axial aft port of the passage and out a plurality of surface ports an outer surface of only the second rotor, wherein the axial aft port extends through one of the plurality of bearing chambers; and
the directing the working fluid through the passage further includes directing the working fluid through an axial segment forming a blind hole in the second rotor and a plurality of radial segments that are axially spaced apart from each other and fluidly connected between the axial segment and the respective plurality of surface ports that are axially spaced apart from each other on the outer surface of the second rotor, to distribute the working fluid about the pair of rotors,
wherein the plurality of surface ports are axially spaced apart at regular intervals along the outer surface of only the second rotor of the pair of rotors, the outer surface of the second rotor that includes the alternating peaks and troughs defined axially along the outer surface of the second rotor so that at least one first surface port of the plurality of surface ports is positioned at or proximate a peak of the alternating peaks and troughs and at least one second surface port of the plurality of surface ports is disposed at or proximate a trough of the alternating peaks and troughs; and
controlling flow of the working fluid through the passage with a flow control orifice located in the passage at a position aft of the plurality of radial segments.