[go: up one dir, main page]
More Web Proxy on the site http://driver.im/

US20130255286A1 - Oil Compensation In A Refrigeration Circuit - Google Patents

Oil Compensation In A Refrigeration Circuit Download PDF

Info

Publication number
US20130255286A1
US20130255286A1 US13/990,865 US201013990865A US2013255286A1 US 20130255286 A1 US20130255286 A1 US 20130255286A1 US 201013990865 A US201013990865 A US 201013990865A US 2013255286 A1 US2013255286 A1 US 2013255286A1
Authority
US
United States
Prior art keywords
oil
compressors
refrigeration circuit
compressor
circuit according
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
US13/990,865
Other languages
English (en)
Inventor
Jan Siegert
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Carrier Corp
Original Assignee
Carrier Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Carrier Corp filed Critical Carrier Corp
Assigned to CARRIER KALTETECHNIK DEUTSCHLAND GMBH reassignment CARRIER KALTETECHNIK DEUTSCHLAND GMBH ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: SIEGERT, JAN
Assigned to CARRIER CORPORATION reassignment CARRIER CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: CARRIER KALTETECHNIK DEUTSCHLAND GMBH
Publication of US20130255286A1 publication Critical patent/US20130255286A1/en
Abandoned legal-status Critical Current

Links

Images

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
    • F25B41/00—Fluid-circulation arrangements
    • 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
    • F25B31/002—Lubrication
    • F25B31/004—Lubrication oil recirculating arrangements
    • 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
    • F25B2400/07—Details of compressors or related parts
    • F25B2400/075—Details of compressors or related parts with parallel compressors

Definitions

  • Refrigeration circuits for circulating a refrigerant and comprising in flow direction of the refrigerant: a heat rejecting heat exchanger, a receiver, an expansion device, an evaporator, and a compressor are widely known and used for refrigeration purposes.
  • Some embodiments include a couple of compressors connected in parallel in order to increase the performance of the refrigeration circuit. Using a couple of compressors in parallel increases not only the performance but also the flexibility of the circuit as individual compressors can be switched on and off in order to adjust the performance provided by the compressor assembly. It further increases the reliability of the circuit as the circuit can be operated even if one of the compressors is broken or not working due to maintenance.
  • the compressors are lubricated by oil circulating through the compressor and flowing by its moving parts.
  • oil circulating through the compressor and flowing by its moving parts When at least two compressor of this type are connected in parallel, there exists the problem that the oil level of the individual compressors will change during operation due to oil which is carried over to the refrigerant and circulates through the refrigeration cycle together with the refrigerant. This transfer of oil between the compressors may result in one or more of the compressors running completely out of oil which may cause severe damage of the respective compressor(s).
  • U.S. Pat. No. 5,586,450 A discloses a refrigeration circuit comprising two compressors. Each compressor has an oil pump with excess capacity relative to lubrication requirements of the respective compressor. The excess capacity is diverted to a common line which connects to each of the compressors in the circuit through a float valve. Each float valve is operated responsive to the oil level in the associated compressor such that oil diverted as excess capacity is supplied to any compressor in the circuit short of oil.
  • Exemplary embodiments of the invention include a refrigeration circuit having at least two compressors.
  • Each compressor includes at least one lubrication point, i.e. a point which is to be supplied with oil when the compressor is operating, and at least one oil pump having an outlet for providing oil to said lubrication point.
  • the outlet of the oil pump of at least one of the compressors is fluidly connected to the lubrication point of at least one other compressor in order to allow said oil pump to provide oil to the lubrication point of said other compressor.
  • Exemplary embodiments of the invention further include a method of operating a refrigeration circuit with at least two compressors, wherein each of the compressors has at least one lubrication point and at least one oil pump with at least one outlet.
  • the method includes the step of supplying oil from the outlet of one of the oil pumps to the lubrication point of at least one other compressor.
  • FIG. 1 shows a schematic view of a refrigeration circuit in accordance with a first embodiment the invention
  • FIG. 2 shows a schematic view of a refrigeration circuit in accordance with a second embodiment the invention
  • FIG. 3 shows a schematic view of a refrigeration circuit in accordance with a third embodiment the invention
  • FIG. 1 shows a schematic view of a refrigeration circuit which is configured for circulating a refrigerant in counter-clockwise direction as indicated by the arrow A.
  • the refrigeration circuit comprises in flow direction of the refrigerant a heat rejecting heat exchanger 2 , which is configured for cooling the refrigerant, a receiver 4 , which is configured for storing the refrigerant, a couple of expansion devices 6 a, 6 b, which are configured for expanding the circulating refrigerant, i. e. reducing the pressure of the refrigerant, and a two evaporators 8 a, 8 b, which are arranged downstream of the expansion devices 6 a, 6 b, respectively, and which are configured for heating and evaporating the expanded refrigerant.
  • the refrigeration circuit may comprise only one expansion device 6 a and only one evaporator 8 a.
  • the refrigeration circuit further includes an assembly 10 of compressors 10 a, 10 b, 10 c which are connected in parallel with their inlets and outlets in order to suck refrigerant leaving the evaporators 8 a, 8 b, compressing the refrigerant and dispensing the compressed refrigerant to the heat rejecting heat exchanger 2 .
  • the assembly 10 includes three compressors 10 a, 10 b, 10 c connected in parallel.
  • compressors 10 a, 10 b, 10 c may be used.
  • Each of the compressors 10 a, 10 b, 10 c comprises an oil sump 20 a, 20 b, 20 c for collecting oil circulating through the compressor 10 a, 10 b, 10 c during operation in order to lubricate the moving parts of the compressors 10 a, 10 b, 10 c.
  • the oil sumps 20 a, 20 b, 20 c of the compressor 10 a, 10 b, 10 c are connected to each other by means of an oil sump compensation line 22 allowing oil to flow from each of the oil sumps 20 a, 20 b, 20 c to the oil sump(s) 20 a, 20 b, 20 c of another compressor 10 a, 10 b, 10 c, in order to perform oil compensation between the oil sumps 20 a, 20 b, 20 c of the compressors 10 a, 10 b, 10 c. Since no oil pumps are involved in this type of oil compensation, this type of oil compensation may be considered as passive oil compensation.
  • the level of oil in one of the oil sumps 20 a, 20 b, 20 c exceeds the level of oil in the oil sump 20 a, 20 b, 20 c of another compressor, this results in a pressure difference between the oil sumps 20 a, 20 b, 20 c of the respective compressors 10 a, 10 b, 10 c, which will generate a flow of oil from the oil sump 20 a, 20 b, 20 c comprising more oil to the oil sump 20 a, 20 b, 20 c comprising less oil.
  • Each of the compressors 10 a, 10 b, 10 c further includes an oil pump 12 a, 12 b, 12 c configured for delivering oil from the respective oil sump 20 a, 20 b, 20 c to the lubrication points, i. e. points which need to be lubricated during the operation of the compressor 10 a, 10 b, 10 c.
  • a refrigeration circuit according to the invention further includes a common oil compensation line 18 fluidly connecting the outlets of the oil pumps 12 a, 12 b, 12 c of the compressors 10 a, 10 b, 10 c with each other and with the lubrication points of the other compressors 10 a, 10 b, 10 c.
  • Said common oil compensation line 18 allows every oil pump 12 a, 12 b, 12 c of each of the compressors 10 a, 10 b, 10 c to deliver oil to the lubrication points of each of the plurality of compressors 10 a, 10 b, 10 c.
  • the lubrication points of the drained compressor 10 a, 10 b, 10 c will be lubricated by oil delivered by at least one oil pump 12 a, 12 b, 12 c of another compressor 10 a, 10 b, 10 c.
  • the oil delivered to said compressor 10 a, 10 b, 10 c via the common oil compensation line 18 will flow to the drained compressor's oil sump 20 a, 20 b, 20 c after it has passed and lubricated the moving parts of said compressor 10 a, 10 b, 10 c.
  • a drained oil sump 20 a, 20 b, 20 c of any of the compressors 10 a, 10 b, 10 c will be refilled by transferring oil from at least one of the other compressors 10 a, 10 b, 10 c via the common oil compensation line 18 to each of the compressors 10 a, 10 b, 10 c, which has run out of oil.
  • switchable valves 14 a, 14 b, 14 c are arranged between the outlets of the oil pumps 12 a, 12 b, 12 c of each of the compressors 10 a, 10 b, 10 c and the common oil compensation line 18 . If one of the compressors 10 a, 10 b, 10 c is switched off for maintenance or due to low load of the refrigeration circuit, the corresponding switchable valve 14 a, 14 b, 14 c may be closed in order to avoid an unnecessary supply of oil to said non-working compressor 10 a, 10 b, 10 c.
  • the oil compensation between the compressors 10 a, 10 b, 10 c can be selectively controlled in order to equalize the oil levels in the plurality of oil sumps 20 a, 20 b, 20 c.
  • At least one of the compressors 10 a, 10 b, 10 c may include a variable speed drive (VSD) 16 which allows to control the speed and the performance of the respective compressor 10 a.
  • VSD variable speed drive
  • receiver 4 is an optional feature of the refrigeration circuit and that the invention may also be applied to refrigeration circuits without a receiver 4 .
  • a refrigeration circuit having a refrigerator 4 may include a flash-gas line extending from the receiver 4 to the inlet of the compressor(s) 8 a, 8 b and being configure for tapping flash gas from the receiver 4 to the compressor(s) 8 a, 8 b bypassing the expansion device(s) 6 a, 6 b and the evaporator(s) 8 a, 8 b.
  • a flash-gas line helps to improve the performance as well as the efficiency of the refrigeration circuit.
  • the refrigeration circuit is a two-stage expansion refrigeration circuit comprising a first, high pressure expansion valve 3 arranged between the outlet of the heat-rejecting heat-exchanger 2 and the receiver 4 and a second, low-pressure expansion devices 6 a, 6 b arranged in flow direction between the outlet of the receiver and the inlet of the evaporator(s) 8 a, 8 b.
  • the refrigerant taken from the receiver 10 is expanded from medium-pressure to low pressure by at least one low-pressure expansion device 6 a, 6 b before entering the evaporator(s) 8 a, 8 b.
  • the two-stage expansion as performed in two-stage expansion refrigeration improves the performance and efficiency of the refrigeration circuit, in particular if CO 2 is used as a refrigerant. CO 2 provides a very efficient refrigerant.
  • FIG. 3 shows a further embodiment, which is similar to the first embodiment shown in FIG. 1 .
  • the oil sumps 20 a, 20 b, 20 c of the compressors 10 a, 10 b, 10 c are not connected by an oil sump compensation line 22 as in the first embodiment shown in FIG. 1 .
  • oil compensation is performed completely via the common oil compensation line 18 fluidly connecting the outlets of the oil pumps 12 a, 12 b, 12 c of the individual compressors 10 a, 10 b, 10 c.
  • oil compensation between the individual oil sumps 20 a, 20 b, 20 c is performed by pumping oil from at least one of the oil sumps 20 a, 20 b, 20 c to the lubrication points of at least one different compressor 10 a, 10 b, 10 c by the oil pumps 12 a, 12 b, 12 c and the common oil compensation line 18 .
  • the oil will then flow from said lubrication points to the oil sump 20 a, 20 b, 20 c of the respective compressor 10 a, 10 b, 10 c refilling said oil sump 20 a, 20 b, 20 c.
  • the space needed for the oil sump compensation line 22 and the costs for providing and maintaining said oil sump compensation line 22 can be saved.
  • the costs for a refrigeration circuit according to the second embodiment are reduced with respect to a refrigeration circuit according to the first embodiment.
  • Exemplary embodiments of the invention as described above allow for an effective and reliable oil compensation between the compressors.
  • it provides a reliable oil supply to all the compressors even if one of the oil pumps is not working or one of the oils sumps has run out of oil. It therefore improves the reliability of a refrigeration circuit comprising a plurality of compressors.
  • outlet of the oil pump of each compressor is fluidly connected to the lubrication points of at least one additional compressor. This ensures a reliable oil supply to the lubrications points of each compressor.
  • every lubrication point of each of the compressors is fluidly connected to the oil pump of at least one different compressor. This ensures a reliable oil supply to the lubrication points of all the compressors.
  • the outlets of the oil pumps of the compressors may be fluidly connected by a common oil compensation line.
  • a common oil compensation line allows to perform oil compensation between the outlets of the oil pumps of all the compressors at low costs.
  • said common line is fluidly connected to the lubrication points of all compressors. This provides reliable oil supply to the lubrication points of all compressors and therefore increases the reliability of the refrigeration circuit.
  • the compressors may include oil sumps and oil pumps which are configured to deliver oil from the respective oil sump to the lubrication points of the respective compressor.
  • Oil sumps provide effective means for collecting and storing an amount of oil within the compressor and providing said oil to an oil pump for delivery to respective lubrication points.
  • the oil sumps of a couple of compressors may be fluidly connected to each other by an oil sump compensation line. Fluidly connecting the oil sumps of a couple of compressors allows easy oil compensation between the compressors by oil flowing directly from one oil sump to the oil sump of another compressor due to different oil pressures in the different oil sumps, the different oil pressures being caused by different oil levels in the different compressors.
  • oil sumps of the compressors are not fluidly connected to each other. This saves the costs for the oil sump compensation line fluidly connecting the oil sumps of the compressors. In this case oil compensation is performed only via the fluidly connected outlets of the oil pumps as described above.
  • At least one of the compressors may include a variable speed drive.
  • a compressor comprising a variable speed drive allows for flexible adjustment of the performance of said compressor. It also allows a finer adjustment of the performance of a set of compressors than the on-/off-switching of one or more of said compressors.
  • a switchable valve may be arranged between the outlet of the oil pump of at least one of the compressors and at least one of the lubrication points.
  • this switchable valve may be a solenoid valve.
  • a switchable valve allows to fluidly separate the respective compressor from the other compressors, in particular if the respective compressor is not running. Separating a non-working compressor from the other compressors allows to avoid an undesirable flow of oil to and from a non-working compressor.
  • a switchable valve may also be arranged between the outlet of the oil pump of at least one of the compressors and the common oil compensation line described before in order to allow to avoid an undesirable flow of oil between a non-working compressor and the common oil compensation line by closing the switchable valve corresponding to the non-working compressor.
  • oil from one of the oil pumps may be supplied to the lubrication points of all the compressors. This ensures that all compressors are reliably supplied with lubricating oil.
  • the operation may also include to supply oil from the oil pumps of all the compressors to the lubrication points of all the compressors. This provides a very efficient and reliable lubrication of the all the compressors.
  • the oil may be delivered through a common oil compensation line fluidly connecting the outlets of the oil pumps of the compressors. This provides a very efficient means for delivering the oil.
  • Operating a refrigeration circuit may include actuating at least one switchable valve arranged between the outlet of the oil pump of one of the compressors and the common line. This allows to avoid an undesirable oil exchange between the common line and a compressor which is not working.
  • the operation may also include to deliver oil from an oil sump formed in at least one of the compressors. Delivering oil from an oil sump, which is formed in at least one of the compressors, provides an efficient way of delivering oil.
  • Operating a refrigeration circuit may further include regulating the speed of at least one of the compressors. This allows to adjust the performance of the compressor or a group of compressors efficiently to the load of the refrigeration circuit.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Compressors, Vaccum Pumps And Other Relevant Systems (AREA)
  • Compressor (AREA)
US13/990,865 2010-12-02 2010-12-02 Oil Compensation In A Refrigeration Circuit Abandoned US20130255286A1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/EP2010/068697 WO2012072139A2 (en) 2010-12-02 2010-12-02 Oil compensation in a refrigeration circuit

Publications (1)

Publication Number Publication Date
US20130255286A1 true US20130255286A1 (en) 2013-10-03

Family

ID=44624912

Family Applications (1)

Application Number Title Priority Date Filing Date
US13/990,865 Abandoned US20130255286A1 (en) 2010-12-02 2010-12-02 Oil Compensation In A Refrigeration Circuit

Country Status (5)

Country Link
US (1) US20130255286A1 (zh)
EP (1) EP2646762B1 (zh)
CN (1) CN103403477B (zh)
ES (1) ES2579436T3 (zh)
WO (1) WO2012072139A2 (zh)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2990739A1 (en) * 2014-08-29 2016-03-02 BI Freezer Srl Process for the external force-feed lubrication of refrigerating compressors
US20170159976A1 (en) * 2015-12-08 2017-06-08 Bitzer Kuehlmaschinenbau Gmbh Cascading oil distribution system
US20170211855A1 (en) * 2016-01-22 2017-07-27 Bitzer Kuehlmaschinenbau Gmbh Oil distribution in multiple-compressor systems utilizing variable speed
US20180160570A1 (en) * 2016-12-02 2018-06-07 Dell Products L.P. Dynamic cooling system
US10571167B2 (en) 2015-03-20 2020-02-25 Carrier Corporation Transportation refrigeration unit with multiple compressors

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3621670A (en) * 1970-01-12 1971-11-23 Vilter Manufacturing Corp Lubricating oil equalizing system
US5094598A (en) * 1989-06-14 1992-03-10 Hitachi, Ltd. Capacity controllable compressor apparatus
US5911289A (en) * 1994-06-17 1999-06-15 Waller; Clive Gregory Oil level control apparatus

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3386262A (en) * 1966-10-31 1968-06-04 Trane Co Refrigeration apparatus with compressors in parallel
DE1915174A1 (de) * 1969-03-25 1970-12-17 Linde Ag Verfahren und Vorrichtung zum automatischen Verdichteroelspiegelausgleich in mehrere Kaeltemittelverdichter mit eingebauten Schmieroelpumpen umfassenden Kaelteanlagen
SU1543204A1 (ru) * 1988-05-12 1990-02-15 Предприятие П/Я А-3304 Холодильна машина
US5586450A (en) 1995-09-25 1996-12-24 Carrier Corporation Plural compressor oil level control
CN1097711C (zh) * 1999-07-13 2003-01-01 清华同方股份有限公司 多台制冷压缩机均油自控装置
KR20080032870A (ko) * 2006-10-11 2008-04-16 엘지전자 주식회사 멀티형 공기조화기의 압축기 오일 회수장치 및오일회수방법

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3621670A (en) * 1970-01-12 1971-11-23 Vilter Manufacturing Corp Lubricating oil equalizing system
US5094598A (en) * 1989-06-14 1992-03-10 Hitachi, Ltd. Capacity controllable compressor apparatus
US5911289A (en) * 1994-06-17 1999-06-15 Waller; Clive Gregory Oil level control apparatus

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2990739A1 (en) * 2014-08-29 2016-03-02 BI Freezer Srl Process for the external force-feed lubrication of refrigerating compressors
US10571167B2 (en) 2015-03-20 2020-02-25 Carrier Corporation Transportation refrigeration unit with multiple compressors
US20170159976A1 (en) * 2015-12-08 2017-06-08 Bitzer Kuehlmaschinenbau Gmbh Cascading oil distribution system
US9939179B2 (en) * 2015-12-08 2018-04-10 Bitzer Kuehlmaschinenbau Gmbh Cascading oil distribution system
US20170211855A1 (en) * 2016-01-22 2017-07-27 Bitzer Kuehlmaschinenbau Gmbh Oil distribution in multiple-compressor systems utilizing variable speed
US10760831B2 (en) * 2016-01-22 2020-09-01 Bitzer Kuehlmaschinenbau Gmbh Oil distribution in multiple-compressor systems utilizing variable speed
EP3405724B1 (en) * 2016-01-22 2024-09-04 BITZER Kühlmaschinenbau GmbH Oil distribution in multiple-compressor systems utilizing variable speed
US20180160570A1 (en) * 2016-12-02 2018-06-07 Dell Products L.P. Dynamic cooling system
US10856449B2 (en) * 2016-12-02 2020-12-01 Dell Products L.P. Dynamic cooling system

Also Published As

Publication number Publication date
ES2579436T3 (es) 2016-08-11
WO2012072139A3 (en) 2012-09-27
EP2646762B1 (en) 2016-03-30
EP2646762A2 (en) 2013-10-09
CN103403477B (zh) 2016-08-10
CN103403477A (zh) 2013-11-20
WO2012072139A2 (en) 2012-06-07

Similar Documents

Publication Publication Date Title
US10634424B2 (en) Oil management for micro booster supermarket refrigeration system
EP2766676B1 (en) Motor cooling and sub-cooling circuits for compressor
JP4013261B2 (ja) 冷凍装置
US7918106B2 (en) Refrigeration system
EP2646762B1 (en) Oil compensation in a refrigeration circuit
US6955058B2 (en) Refrigerant cycle with tandem economized and conventional compressors
EP2910871B1 (en) Refrigeration device
US20060101845A1 (en) Compressor oil recovering apparatus and multi-unit air conditioner equiped with the same
EP2283284B1 (en) Refrigeration cycle and method for operating the same
CN108139123B (zh) 用于切换压缩机容量的方法
EP1671067B1 (en) Distributed condensing units
KR100209036B1 (ko) 압축기 오일 레벨 제어
CN107850356B (zh) 具有液体分离器应用的热回收系统
JP2007218565A (ja) 冷凍装置
JP2007093017A (ja) 冷凍装置
EP2732222B1 (en) Refrigeration circuit with oil compensation
JP2004301461A (ja) 空気調和装置
CN107621092B (zh) 低温涡轮制冷机
EP4301103A1 (en) Modular cooling system
KR20060081937A (ko) 냉동시스템
CN211424747U (zh) 无油轴承供液系统及空调机组
WO2022224304A1 (ja) 熱源ユニット
JP6833065B2 (ja) 冷凍装置および室外機
CN110986429A (zh) 无油轴承供液系统及空调机组
KR20060078093A (ko) 공기조화기

Legal Events

Date Code Title Description
AS Assignment

Owner name: CARRIER KALTETECHNIK DEUTSCHLAND GMBH, GERMANY

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:SIEGERT, JAN;REEL/FRAME:030521/0786

Effective date: 20110103

Owner name: CARRIER CORPORATION, CONNECTICUT

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:CARRIER KALTETECHNIK DEUTSCHLAND GMBH;REEL/FRAME:030521/0974

Effective date: 20110104

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION