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US20140069122A1 - Apparatus and method for controlling refrigerant temperature in a heat pump or refrigeration apparatus - Google Patents

Apparatus and method for controlling refrigerant temperature in a heat pump or refrigeration apparatus Download PDF

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Publication number
US20140069122A1
US20140069122A1 US14/115,057 US201214115057A US2014069122A1 US 20140069122 A1 US20140069122 A1 US 20140069122A1 US 201214115057 A US201214115057 A US 201214115057A US 2014069122 A1 US2014069122 A1 US 2014069122A1
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US
United States
Prior art keywords
compressor
refrigerant
heat exchanger
reduced temperature
temperature refrigerant
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US14/115,057
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English (en)
Inventor
Douglas Lloyd LOCKHART
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Individual
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Individual
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Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US14/115,057 priority Critical patent/US20140069122A1/en
Publication of US20140069122A1 publication Critical patent/US20140069122A1/en
Abandoned legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B30/00—Heat pumps
    • F25B30/02—Heat pumps of the compression type
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B13/00—Compression machines, plants or systems, with reversible cycle
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B31/00—Compressor arrangements
    • F25B31/006—Cooling of compressor or motor
    • F25B31/008—Cooling of compressor or motor by injecting a liquid
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2313/00—Compression machines, plants or systems with reversible cycle not otherwise provided for
    • F25B2313/027—Compression machines, plants or systems with reversible cycle not otherwise provided for characterised by the reversing means
    • F25B2313/02741—Compression machines, plants or systems with reversible cycle not otherwise provided for characterised by the reversing means using one four-way valve
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2400/00—General features or devices for refrigeration machines, plants or systems, combined heating and refrigeration systems or heat-pump systems, i.e. not limited to a particular subgroup of F25B
    • F25B2400/16—Receivers

Definitions

  • the present disclosure relates to compressors for heat pump or refrigeration apparatus.
  • a typical refrigeration cycle is a closed loop system which uses a refrigerant having a low boiling point to produce a relative coldness.
  • a compressor compresses the refrigerant in order to increase its pressure.
  • the refrigerant gas temperature also rises and subsequently the gas then flows through a heat exchanger to transfer heat to the adjacent medium in the heat exchanger.
  • the heat dissipates the refrigerant cools and condenses to a liquid.
  • the liquid then flows through an expansion valve which causes the refrigerant to expand and change phases into a gas.
  • the cold gas then circulates into a second heat exchanger and absorbs heat and then passes into the compressor where the cycle repeats.
  • Lubricant is provided in the compressor 12 to lubricate the compressor crankcase and other compressor components. Proper lubrication helps to avoid compressor failures, which can be costly both in terms of production down time and part replacement.
  • the lubricant is intended to remain primarily in the compressor crankcase, however, the lubricant often migrates to other parts of a refrigeration apparatus.
  • the temperature output of a refrigeration apparatus is limited by the effective temperature range of the lubricant and the compression process of the compressor.
  • lubricants may break down over time in response to the high temperatures in the compressor.
  • the degraded lubricant may flow throughout the compressor and may cause compressor failure.
  • an apparatus including: a compressor comprising a pair of ports in fluid communication with first and second heat exchangers and a reduced temperature refrigerant inlet for receiving reduced temperature refrigerant; and an expansion device coupled between the first and second heat exchangers for reducing a pressure of refrigerant flowing from one of the first and second heat exchangers to the other of the first and second heat exchangers; wherein the compressor, the first heat exchanger, the expansion device and the second heat exchanger are arranged in a loop to operate as a refrigeration or heat pump apparatus.
  • a method including: compressing a refrigerant during a compression step of a refrigeration cycle; and injecting a reduced temperature refrigerant into a compressor part-way through the compression step.
  • FIG. 1 is a cycle diagram of an apparatus according to an embodiment
  • FIG. 2 is a schematic top sectional view of a scroll compressor.
  • the following describes an apparatus and method of compressing a refrigerant during a compression step of a refrigeration cycle; and injecting a reduced temperature refrigerant into a compressor part-way through the compression step.
  • an apparatus 10 is schematically shown by way of a cycle diagram.
  • the apparatus 10 is generally a refrigeration apparatus, which may also be referred to as a heat pump.
  • the components of the apparatus 10 are arranged in a loop and refrigerant flows through the apparatus 10 in a first direction to generate heat at a first side of the apparatus 10 .
  • the flow may be reversed to switch the side of the apparatus 10 at which heat is generated.
  • the apparatus 10 includes a compressor 12 , first heat exchanger 14 and second heat exchanger 16 .
  • a four-way reversing valve 18 is located between the compressor 12 and the heat exchangers 14 , 16 to reverse the direction of fluid flow.
  • First heat exchanger 14 and second heat exchanger 16 are both operable as an evaporator and a condenser depending on the direction of fluid flow through the apparatus 10 .
  • a first heat exchange conduit 28 communicates with the first heat exchanger 14 to transfer heat to the first heat exchanger 14 when the first heat exchanger 14 is operating as an evaporator and remove heat from the first heat exchanger 14 when the first heat exchanger 14 is operating as a condenser.
  • a second heat exchange conduit 30 communicates with the second heat exchanger 16 to transfer heat to the second heat exchanger 16 when the second heat exchanger 16 is operating as an evaporator and remove heat from the second heat exchanger 16 when the second heat exchanger 16 is operating as a condenser.
  • the apparatus 10 further includes drive mechanisms (not shown) for pumping fluid through the first and second heat exchange conduits 28 , 30 .
  • a receiver 20 is located between the heat exchangers 14 , 16 . Refrigerant flowing from the first heat exchanger 14 enters the receiver 20 before flowing into the second heat exchanger 16 . Similarly, when flow is reversed, fluid flowing from the second heat exchanger 16 enters the receiver 20 before flowing into the first heat exchanger 18 .
  • the receiver 20 is a reservoir for storing high pressure liquid. A volume of the receiver 20 is sized to compensate for expansion and contraction of the refrigerant in the constant volume apparatus 10 .
  • a first valve 22 is located between the first heat exchanger 14 and the receiver 20 and a second 24 valve is located between the second heat exchanger 16 and the receiver 20 .
  • Both valves 22 , 24 are capable of operating as expansion valves or as check valves, which are also referred to as one-way valves.
  • the mode of operation of the valves 22 , 24 depends on the direction of fluid flow through the apparatus 10 .
  • the valve 22 , 24 that is located adjacent to an inlet of the heat exchanger operating as an evaporator operates as an expansion valve to reduce a pressure of the fluid entering the heat exchanger 14
  • the valve 22 , 24 that is located adjacent to an exit of the condenser operates as a check valve.
  • An accumulator 26 is located between the four-way reversing valve 18 and the compressor 12 .
  • the accumulator 26 is an optional component of the apparatus 10 and is generally provided to store excess liquid refrigerant and lubricant that may not have boiled off during evaporation.
  • Conduits such as pipes, for example, are disposed between components of the apparatus 10 for conveying refrigerant therethrough.
  • Conduit 32 is coupled between the compressor 12 and the four-way reversing valve 18 .
  • Conduit 34 is coupled between the four-way reversing valve 18 and the first heat exchanger 14 .
  • Conduits 36 and 38 are coupled between the first heat exchanger 14 and the valve 22 and the valve 22 and the receiver 20 , respectively.
  • Conduits 40 and 42 are coupled between the receiver 20 and the valve 24 and the valve 24 and the second heat exchanger 16 , respectively.
  • Conduit 44 is coupled between the second heat exchanger 16 and the four-way reversing valve 18 .
  • Conduit 46 is coupled between the four-way reversing valve 18 and the accumulator 26 and conduit 48 is coupled between the accumulator 26 and the compressor 12 .
  • Conduits 32 and 48 are coupled to ports 50 and 52 , respectively, of the compressor 12 .
  • the port 50 is an outlet port and the port 52 in an inlet port.
  • the compressor 12 may have more than one inlet port 52 .
  • a scroll compressor which is shown schematically in FIG. 2 , generally includes two inlet ports for receiving refrigerant from the evaporator.
  • refrigerant is compressed between two scroll plates that are nested together. One plate may be stationary while the other plate moves in an orbital path.
  • Refrigerant is received through inlet ports at the perimeter of the scroll and as the plate orbits, an enclosed volume containing the refrigerant is transferred toward a decreased volume region at the center of the scroll. As the volume decreases, the refrigerant is compressed and discharged through an outlet port.
  • the compressor 12 further includes an injection inlet 54 for receiving a reduced temperature refrigerant from the receiver 20 .
  • Conduit 56 is coupled between the receiver 20 and an expansion valve 58 and conduit 60 is coupled between the expansion valve 58 and inlet 54 of the compressor 12 to facilitate delivery of the refrigerant to the compressor 12 .
  • the expansion valve 58 reduces a pressure of the refrigerant prior to the refrigerant entering the compressor 12 .
  • the injection inlet 54 is located in interior or middle scrolls of the flanks of the scroll compressor.
  • the injection inlet 54 facilitates injection of refrigerant into the compressor 12 through the inlet 54 part-way through the compression step of the refrigeration cycle.
  • compressor outlet temperature is maintained below 300° F. in order to avoid damage due to lubricant breakdown.
  • One or more of compressor outlet temperature, compressor motor temperature and compressor flank temperature are measured in order to determine when and how much of the reduced temperature refrigerant may be injected into the injection inlet 54 . Methods for measuring compressor temperatures are well known in the art and therefore will not be described further.
  • the injection of reduced temperature refrigerant reduces the temperature of the refrigerant proceeding through the compression step and exiting the compressor 12 .
  • the reduced temperature refrigerant is less likely to cause the lubricant in the compressor to break down, which may result in an increased operating life of the compressor 12 .
  • the refrigerant used in the apparatus 10 is Trifluoroiodomethane (CF3I), which may also be referred to as Iodotrifluoromethane, Monoiodotrifluoromethane, Trifluoromethyl iodide, Perfluoromethyl iodide or Freon 13T1.
  • the chemical composition of the Trifluoroiodomethane includes one carbon atom combined with 3 flourine atoms and one Iodine atom. Sesquiterpene, which is a stabilizer may be added to the refrigerant
  • the refrigerant may be one of other blends fluorinated carbon compounds to facilitate the higher efficiency and work well with mid-compression refrigeration injection.
  • the refrigerants generally have a low GWP (global warming potential) and are ozone friendly.
  • heat exchanger 14 is operating as a condenser and heat exchanger 16 is operating as an evaporator.
  • Low pressure refrigerant enters the compressor 12 through port 52 and is compressed.
  • reduced temperature refrigerant which has a lower temperature than the refrigerant that is in the compressor 12
  • the reduced temperature refrigerant flows from the receiver 20 , through the expansion valve 58 , to enter the compressor 12 with a pressure that is lower than the pressure of the refrigerant in the receiver 20 .
  • the refrigerant entering the compressor 12 through the inlet 54 has an absolute pressure that is approximately mid-way between the absolute pressure at the inlet port 52 and the absolute pressure at the outlet port 50 .
  • the reduced temperature refrigerant mixes with the refrigerant in the compressor 12 and exits the compressor 12 through conduit 32 as a high pressure, high temperature gas.
  • the refrigerant exiting the compressor 12 is at a high temperature, however, the temperature is less than the temperature would have been without the addition of the reduced temperature refrigerant, which facilitates protection of the lubricant and the moving mechanical parts of the compressor and other components of the apparatus 10 .
  • the gas exiting the compressor 12 flows through the four-way reversing valve 18 , through conduit 34 and enters the first heat exchanger 14 .
  • the refrigerant flows through the first heat exchanger 14 , the refrigerant is in indirect contact with fluid flowing through the first heat exchange conduit 28 to remove heat from the refrigerant.
  • the condensed refrigerant exits the heat exchanger 14 , flows through conduit 36 and travels past valve 22 , which functions as a check valve.
  • the condensed refrigerant then flows through conduit 38 and into the receiver 20 .
  • the condensed refrigerant exits the receiver 20 flows through conduit 40 and travels past the valve 24 , which functions as an expansion valve where the pressure of the refrigerant is reduced to facilitate expansion and lowering of the refrigerant temperature.
  • the refrigerant then flows through conduit 42 and into the second heat exchanger 16 .
  • the refrigerant is in indirect contact with fluid flowing through the second heat exchange conduit 30 and heat is absorbed by the refrigerant.
  • the refrigerant vaporizes and exits the second heat exchanger 16 through conduit 44 and flows into the four-way reversing valve 18 . From the four-way reversing valve 18 , the refrigerant flows through conduit 46 to enter the accumulator 26 .
  • the refrigerant then exits the accumulator 26 through conduit 48 and flows into the compressor 12 to begin the cycle again.
  • the refrigerant temperature is maintained below a breakdown temperature of the lubricant.
  • the refrigerant temperature is maintained 25 to 50 degrees Fahrenheit below the lubricant breakdown temperature.
  • POE Polyolester
  • HFC Hydro fluorocarbon
  • the four-way reversing valve 18 is eliminated from the embodiment of FIG. 1 and the apparatus 10 is operable in a single direction.
  • a motor of the compressor 12 includes a frequency drive for controlling the compressor motor speed.
  • a frequency drive for controlling the compressor motor speed.
  • the reduced temperature refrigerant may be injected into the compressor 12 in response to a temperature at the outlet port 50 of the compressor 12 being within a predetermined temperature range. In one example, the reduced temperature refrigerant is injected into the compressor when the temperature at the outlet port 50 is between 250 and 275 degrees Fahrenheit.
  • the apparatus 10 described herein may include any type of compressor that is capable of compound and/or inter-stage compression.
  • a scroll compressor is provided as an example and is not intended to be limiting.
  • the operating life of the lubricant and therefore the operating life of the compressor 12 and other components of the heat pump/refrigeration apparatus may be extended.
  • the efficiency of the refrigeration apparatus 10 may be increased.
  • the operating time of the refrigeration apparatus 10 may be reduced resulting in less energy consumed.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Applications Or Details Of Rotary Compressors (AREA)
  • Rotary Pumps (AREA)
US14/115,057 2011-05-05 2012-03-30 Apparatus and method for controlling refrigerant temperature in a heat pump or refrigeration apparatus Abandoned US20140069122A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US14/115,057 US20140069122A1 (en) 2011-05-05 2012-03-30 Apparatus and method for controlling refrigerant temperature in a heat pump or refrigeration apparatus

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US201161482923P 2011-05-05 2011-05-05
US14/115,057 US20140069122A1 (en) 2011-05-05 2012-03-30 Apparatus and method for controlling refrigerant temperature in a heat pump or refrigeration apparatus
PCT/CA2012/000328 WO2012149629A1 (fr) 2011-05-05 2012-03-30 Appareil et procédé permettant de contrôler la température du fluide frigorigène dans un appareil de pompe à chaleur ou de réfrigération

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US20140069122A1 true US20140069122A1 (en) 2014-03-13

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US (1) US20140069122A1 (fr)
CA (1) CA2834803A1 (fr)
WO (1) WO2012149629A1 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20170010052A1 (en) * 2014-02-17 2017-01-12 Siemens Aktiengesellschaft Method And Device For Charging A Stratified Thermal Energy Store
US9835360B2 (en) 2009-09-30 2017-12-05 Thermo Fisher Scientific (Asheville) Llc Refrigeration system having a variable speed compressor
US10401047B2 (en) * 2014-06-27 2019-09-03 Mitsubishi Electric Corporation Refrigeration cycle apparatus
CN113631873A (zh) * 2019-04-02 2021-11-09 三菱电机株式会社 热源侧单元以及制冷循环装置

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4344297A (en) * 1980-03-20 1982-08-17 Daikin Kogyo Co., Ltd. Refrigeration system
US4852364A (en) * 1987-10-23 1989-08-01 Sporlan Valve Company Expansion and check valve combination
US5140828A (en) * 1990-06-14 1992-08-25 Hitachi, Ltd. Refrigeration cycle apparatus
US6305187B1 (en) * 2000-02-14 2001-10-23 Hiroaki Tsuboe Air-conditioner, outdoor unit and refrigeration unit
US20090199581A1 (en) * 2008-02-07 2009-08-13 Miitsubishi Electric Corporation Heat pump water heater outdoor unit and heat pump water heater
US20090283712A1 (en) * 2008-05-15 2009-11-19 Honeywell International Inc. Sesquiterpene stabilized compositions
US7824160B2 (en) * 2005-06-10 2010-11-02 Hitachi Appliances, Inc. Scroll compressor and refrigerating apparatus

Family Cites Families (3)

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Publication number Priority date Publication date Assignee Title
JPH09196478A (ja) * 1996-01-23 1997-07-31 Nippon Soken Inc 冷凍サイクル
US6615598B1 (en) * 2002-03-26 2003-09-09 Copeland Corporation Scroll machine with liquid injection
US7895850B2 (en) * 2005-04-15 2011-03-01 Comforture, L.P. Modulating proportioning reversing valve

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4344297A (en) * 1980-03-20 1982-08-17 Daikin Kogyo Co., Ltd. Refrigeration system
US4852364A (en) * 1987-10-23 1989-08-01 Sporlan Valve Company Expansion and check valve combination
US5140828A (en) * 1990-06-14 1992-08-25 Hitachi, Ltd. Refrigeration cycle apparatus
US6305187B1 (en) * 2000-02-14 2001-10-23 Hiroaki Tsuboe Air-conditioner, outdoor unit and refrigeration unit
US7824160B2 (en) * 2005-06-10 2010-11-02 Hitachi Appliances, Inc. Scroll compressor and refrigerating apparatus
US20090199581A1 (en) * 2008-02-07 2009-08-13 Miitsubishi Electric Corporation Heat pump water heater outdoor unit and heat pump water heater
US20090283712A1 (en) * 2008-05-15 2009-11-19 Honeywell International Inc. Sesquiterpene stabilized compositions

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9835360B2 (en) 2009-09-30 2017-12-05 Thermo Fisher Scientific (Asheville) Llc Refrigeration system having a variable speed compressor
US10072876B2 (en) 2009-09-30 2018-09-11 Thermo Fisher Scientific (Asheville) Llc Refrigeration system having a variable speed compressor
US10816243B2 (en) 2009-09-30 2020-10-27 Thermo Fisher Scientific (Asheville) Llc Refrigeration system having a variable speed compressor
US10845097B2 (en) 2009-09-30 2020-11-24 Thermo Fisher Scientific (Asheville) Llc Refrigeration system having a variable speed compressor
US20170010052A1 (en) * 2014-02-17 2017-01-12 Siemens Aktiengesellschaft Method And Device For Charging A Stratified Thermal Energy Store
US10401047B2 (en) * 2014-06-27 2019-09-03 Mitsubishi Electric Corporation Refrigeration cycle apparatus
CN113631873A (zh) * 2019-04-02 2021-11-09 三菱电机株式会社 热源侧单元以及制冷循环装置

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Publication number Publication date
CA2834803A1 (fr) 2012-11-08
WO2012149629A1 (fr) 2012-11-08

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