# US 10,480,831 B2 · Compressor bearing cooling > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,480,831 B2 - Document ID: US10480831B2 - Status: Granted - Kind: B2 - Application number: 14/779,155 - Filed: 2014-01-27 - Published: 2016-02-18 - Granted: 2019-11-19 - Earliest claimed: 2013-03-25 - Assignees: Carrier Corporation - Applicants: Carrier Corporation - Inventors: Ulf J. Jonsson; Vishnu M. Sishtla; Zaffir A. Chaudhry - Web page: https://patentgrep.com/patent/US10480831B2 ## CPC - F25B 1/053: of turbine type - F25B 31/00: Compressor arrangements - F25B 31/008: {by injecting a liquid} - F25B 41/00: Fluid-circulation arrangements - F25B 25/005: {using primary and secondary systems} - F25B 2339/047: Water-cooled condensers - F25B 2341/0012: Ejectors with the cooled primary flow at high pressure - F25B 2341/0015: using two or more ejectors - F25B 2400/13: Economisers - F25B 2400/25: Liquid pumps - F25B 2500/16: Lubrication - F25B: REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS ## Abstract A vapor compression system (20) comprises a compressor (22) having one or more bearing systems (66, 68) supporting a rotor and/or one or more working elements (44). One or more bearing feed passages (114) are coupled to the bearings to pass fluid along a supply flowpath to the bearings. A mechanical pump (130; 330) is positioned to drive fluid along the supply flowpath. An ejector (140, 150) has a motive flow inlet (142, 152) coupled to the mechanical pump to receive refrigerant from the mechanical pump. ## Claims ### Claim 1 A vapor compression system comprising: a compressor comprising: a housing assembly having a suction port and a discharge port and a motor compartment; an electric motor having a stator within the motor compartment and a rotor within the stator, the rotor being mounted for rotation about a rotor axis; one or more working elements coupled to the rotor to be driven by the rotor in at least a first condition so as to draw fluid in through the suction port and discharge said fluid out from the discharge port; one or more bearings supporting the rotor and/or the one or more working elements, and one or more bearing feed passages coupled to the one or more bearings to pass fluid along a supply flowpath to the one or more bearings; a mechanical pump positioned to drive fluid along the supply flowpath to the one or more bearings; a first heat exchanger downstream of the discharge port along a refrigerant primary flowpath in a first operational mode; an expansion device downstream of the first heat exchanger along the primary flowpath in the first operational mode; and a second heat exchanger downstream of the expansion device and coupled to the suction port to return refrigerant in the first operational mode, the vapor compression system further comprising: one or more bearing drain passages positioned to pass a bearing drain flow of said fluid from the motor compartment to the second heat exchanger; an ejector having: a motive flow inlet, coupled to the mechanical pump to receive refrigerant from the mechanical pump; a suction flow inlet; and an outlet. ### Claim 2 (depends on 1) The vapor compression system of claim 1 wherein: a discharge flowpath from the outlet of the ejector at least partially feeds back to the mechanical pump. ### Claim 3 (depends on 1) The vapor compression system of claim 1 wherein: the supply flowpath passes through the ejector from the suction flow inlet to the outlet in at least one operational condition. ### Claim 4 (depends on 1) The vapor compression system of claim 1 wherein: a suction flowpath of the ejector extends from the second heat exchanger to the suction flow inlet of the ejector. ### Claim 5 (depends on 1) The vapor compression system of claim 1 wherein: a motive flowpath of the ejector branches from the supply flowpath downstream of the mechanical pump and extends to the motive flow inlet. ### Claim 6 (depends on 1) The vapor compression system of claim 1 wherein: the compressor is a centrifugal compressor; and the one or more working elements comprises one or more impellers. ### Claim 7 (depends on 6) The vapor compression system of claim 6 wherein: the one or more impellers is a single impeller mounted to the rotor for direct coaxial rotation therewith. ### Claim 8 (depends on 1) The vapor compression system of claim 1 wherein one or more of: the vapor compression system is a chiller; the vapor compression system has a refrigerant charge selected from the group consisting of low pressure refrigerants and medium pressure refrigerants; the vapor compression system has a refrigerant charge selected from the group consisting of HFC refrigerants and HFO refrigerants; the vapor compression system has a refrigerant charge selected from the group consisting of R1233zd, R1234yf, R1234ze, and R134a; and/or the mechanical pump is a gear pump, a centrifugal pump, a regenerative pump, a screw pump, or a vane pump. ### Claim 9 (depends on 1) The vapor compression system of claim 1 further comprising: a controller configured to: start the mechanical pump prior to starting the compressor. ### Claim 10 (depends on 1) The vapor compression system of claim 1 wherein the fluid comprises liquid refrigerant. ### Claim 11 A vapor compression system comprising: a compressor comprising: a housing assembly having a suction port and a discharge port and a motor compartment; an electric motor having a stator within the motor compartment and a rotor within the stator, the rotor being mounted for rotation about a rotor axis; one or more working elements coupled to the rotor to be driven by the rotor in at least a first condition so as to draw fluid in through the suction port and discharge said fluid out from the discharge port; one or more bearings supporting the rotor and/or the one or more working elements, and one or more bearing feed passages coupled to the one or more bearings to pass fluid along a supply flowpath to the one or more bearings; a mechanical pump positioned to drive fluid along the supply flowpath to the one or more bearings; a first heat exchanger downstream of the discharge port along a refrigerant primary flowpath in a first operational mode; an expansion device downstream of the first heat exchanger along the primary flowpath in the first operational mode; and a second heat exchanger downstream of the expansion device and coupled to the suction port to return refrigerant in the first operational mode, the vapor compression system further comprising: a first ejector having: a motive flow inlet, coupled to the mechanical pump to receive refrigerant from the mechanical pump; a suction flow inlet; and an outlet; and a second ejector having: a motive flow inlet; a suction flow inlet; and an outlet, wherein: a motive flowpath of the second ejector branching from the supply flowpath downstream of the mechanical pump and extending to the motive flow inlet of the second ejector; a suction flowpath of the second ejector extends from the second heat exchanger to the suction flow inlet of second ejector; and an outlet flowpath of the second ejector feeds back from the outlet of second ejector to the suction flow inlet of the first ejector. ### Claim 12 (depends on 11) The vapor compression system of claim 11 wherein: the motive flow inlet of the first ejector receives fluid from the first heat exchanger; and the outlet flow path of second ejector feeds back to the first heat exchanger. ### Claim 13 (depends on 11) The vapor compression system of claim 11 wherein: the motive flow inlet of the first ejector receives fluid from a sump of the first heat exchanger; and the outlet flowpath of second ejector feeds back to the sump. ### Claim 14 A vapor compression system comprising: a compressor comprising: a housing assembly having a suction port and a discharge port and a motor compartment; an electric motor having a stator within the motor compartment and a rotor within the stator, the rotor being mounted for rotation about a rotor axis; one or more working elements coupled to the rotor to be driven by the rotor in at least a first condition so as to draw fluid in through the suction port and discharge said fluid out from the discharge port; one or more bearings supporting the rotor and/or the one or more working elements, and one or more bearing feed passages coupled to the one or more bearings to pass fluid along a supply flowpath to the one or more bearings; a mechanical pump positioned to drive fluid along the supply flowpath to the one or more bearings; a first heat exchanger downstream of the discharge port along a refrigerant primary flowpath in a first operational mode; an expansion device downstream of the first heat exchanger along the primary flowpath in the first operational mode; and a second heat exchanger downstream of the expansion device and coupled to the suction port to return refrigerant in the first operational mode; an ejector having: a motive flow inlet, coupled to the mechanical pump to receive refrigerant from the mechanical pump; a suction flow inlet; and an outlet; and a controller configured to: start the mechanical pump prior to starting the compressor; and turn off the mechanical pump and leave the compressor running when a threshold condition has been sensed. ### Claim 15 A method for operating a vapor compression system, the vapor compression system comprising: a compressor comprising: a housing assembly having a suction port and a discharge port and a motor compartment; an electric motor having a stator within the motor compartment and a rotor within the stator, the rotor being mounted for rotation about a rotor axis; one or more working elements coupled to the rotor to be driven by the rotor in at least a first condition so as to draw fluid in through the suction port and discharge said fluid out from the discharge port; one or more bearings supporting the rotor and/or the one or more working elements, and one or more bearing feed passages coupled to the one or more bearings to pass fluid along a supply flowpath to the one or more bearings; a mechanical pump positioned to drive fluid along the supply flowpath to the one or more bearings; a first heat exchanger downstream of the discharge port along a refrigerant primary flowpath in a first operational mode; an expansion device downstream of the first heat exchanger along the primary flowpath in the first operational mode; and a second heat exchanger downstream of the expansion device and coupled to the suction port to return refrigerant in the first operational mode; and an ejector having: a motive flow inlet, coupled to the mechanical pump to receive refrigerant from the mechanical pump; a suction flow inlet; and an outlet, the method comprising: starting the mechanical pump; after the starting of the mechanical pump, starting the electric motor to draw the fluid in through the suction port and discharge the fluid from the discharge port; and turning the mechanical pump off while continuing to run the electric motor. ### Claim 16 (depends on 15) The method of claim 15 wherein: the electric motor is started after a first threshold condition is sensed; and the mechanical pump is turned off after a second threshold condition is sensed. ### Claim 17 (depends on 15) The method of claim 15 further comprising: monitoring a flow or pressure parameter; and responsive to the said flow or pressure parameter indicating an insufficiency of flow, restarting the mechanical pump while continuing the run the electric motor. ### Claim 18 (depends on 15) The method of claim 15 further comprising: restarting the mechanical pump while continuing to run the electric motor; turning the electric motor off while continuing to run the mechanical pump; and turning the mechanical pump off after turning the motor off.