JP2017172923A - Refrigerating device - Google Patents

Refrigerating device Download PDF

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Publication number
JP2017172923A
JP2017172923A JP2016061616A JP2016061616A JP2017172923A JP 2017172923 A JP2017172923 A JP 2017172923A JP 2016061616 A JP2016061616 A JP 2016061616A JP 2016061616 A JP2016061616 A JP 2016061616A JP 2017172923 A JP2017172923 A JP 2017172923A
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pressure
refrigerant
compressor
refrigerator
mpa
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Inventor
裕輔 倉田
Yusuke Kurata
裕輔 倉田
三原　一彦
Kazuhiko Mihara
一彦 三原
雄一 伊澤
Yuichi Izawa
雄一 伊澤
桑原　修
Osamu Kuwabara
修 桑原
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Panasonic Intellectual Property Management Co Ltd
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Panasonic Intellectual Property Management Co Ltd
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Priority to JP2016061616A priority Critical patent/JP2017172923A/en
Priority to CN201610741304.2A priority patent/CN107228520A/en
Priority to US15/249,944 priority patent/US20170276416A1/en
Publication of JP2017172923A publication Critical patent/JP2017172923A/en
Pending legal-status Critical Current

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    • 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
    • F25B41/20—Disposition of valves, e.g. of on-off valves or flow control valves
    • 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
    • F25D—REFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
    • F25D13/00—Stationary devices, e.g. cold-rooms
    • 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
    • F25B1/00—Compression machines, plants or systems with non-reversible cycle
    • F25B1/10—Compression machines, plants or systems with non-reversible cycle with multi-stage compression
    • 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
    • F25B41/00—Fluid-circulation arrangements
    • F25B41/30—Expansion means; Dispositions thereof
    • F25B41/39—Dispositions with two or more expansion means arranged in series, i.e. multi-stage expansion, on a refrigerant line leading to the same evaporator
    • 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
    • F25B49/00—Arrangement or mounting of control or safety devices
    • F25B49/02—Arrangement or mounting of control or safety devices for compression type machines, plants or systems
    • 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
    • F25B49/00—Arrangement or mounting of control or safety devices
    • F25B49/02—Arrangement or mounting of control or safety devices for compression type machines, plants or systems
    • F25B49/022—Compressor control 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
    • F25B9/00—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point
    • F25B9/002—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point characterised by the refrigerant
    • F25B9/008—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point characterised by the refrigerant the refrigerant being carbon dioxide
    • 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
    • F25B2309/00—Gas cycle refrigeration machines
    • F25B2309/06—Compression machines, plants or systems characterised by the refrigerant being carbon dioxide
    • F25B2309/061—Compression machines, plants or systems characterised by the refrigerant being carbon dioxide with cycle highest pressure above the supercritical pressure
    • 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
    • F25B2400/072—Intercoolers therefor
    • 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
    • F25B2400/13—Economisers
    • 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
    • F25B2400/23—Separators
    • 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
    • F25B2600/00—Control issues
    • F25B2600/02—Compressor control
    • F25B2600/025—Compressor control by controlling speed
    • F25B2600/0253—Compressor control by controlling speed with variable speed
    • 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
    • F25B2600/00—Control issues
    • F25B2600/02—Compressor control
    • F25B2600/027—Compressor control by controlling pressure
    • F25B2600/0271—Compressor control by controlling pressure the discharge pressure
    • 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
    • F25B2600/00—Control issues
    • F25B2600/25—Control of valves
    • F25B2600/2513—Expansion valves
    • 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
    • F25B2700/00—Sensing or detecting of parameters; Sensors therefor
    • F25B2700/19—Pressures
    • F25B2700/193—Pressures of the compressor
    • F25B2700/1931—Discharge pressures
    • 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
    • F25B2700/00—Sensing or detecting of parameters; Sensors therefor
    • F25B2700/19—Pressures
    • F25B2700/193—Pressures of the compressor
    • F25B2700/1933—Suction pressures
    • 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
    • F25B2700/00—Sensing or detecting of parameters; Sensors therefor
    • F25B2700/21—Temperatures
    • F25B2700/2106—Temperatures of fresh outdoor air
    • 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
    • F25B2700/00—Sensing or detecting of parameters; Sensors therefor
    • F25B2700/21—Temperatures
    • F25B2700/2109—Temperatures of a separator
    • 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
    • F25B2700/00—Sensing or detecting of parameters; Sensors therefor
    • F25B2700/21—Temperatures
    • F25B2700/2115—Temperatures of a compressor or the drive means therefor
    • F25B2700/21151—Temperatures of a compressor or the drive means therefor at the suction side of the compressor
    • 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
    • F25B2700/00—Sensing or detecting of parameters; Sensors therefor
    • F25B2700/21—Temperatures
    • F25B2700/2115—Temperatures of a compressor or the drive means therefor
    • F25B2700/21152—Temperatures of a compressor or the drive means therefor at the discharge side of the compressor
    • 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
    • F25B2700/00—Sensing or detecting of parameters; Sensors therefor
    • F25B2700/21—Temperatures
    • F25B2700/2116—Temperatures of a condenser
    • F25B2700/21163—Temperatures of a condenser of the refrigerant at the outlet of the condenser
    • 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
    • F25B5/00—Compression machines, plants or systems, with several evaporator circuits, e.g. for varying refrigerating capacity
    • F25B5/02—Compression machines, plants or systems, with several evaporator circuits, e.g. for varying refrigerating capacity arranged in parallel
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
    • Y02B30/70—Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Devices That Are Associated With Refrigeration Equipment (AREA)

Abstract

PROBLEM TO BE SOLVED: To provide a refrigerating device which can reduce a refrigerator outlet pressure even during an overload condition, and which can increase refrigeration capacity by performing liquefaction of a refrigerant in an intermediate cooler.SOLUTION: A control device 60 controls in such a manner that the opening of a decompression motor-operated valve 31 on the upstream side of an intermediate cooler 30 is reduced when an outlet pressure of a refrigerator 2 becomes higher than a critical pressure. Thereby, in the intermediate cooler 30, liquefaction of a refrigerant is performed by gas liquid separation of the refrigerant, so that the refrigerator outlet pressure can be lower than the critical pressure, and a liquid refrigerant can be delivered to a show case 3. As a result, specific enthalpy of the refrigerant on an inlet side of main throttle means 41 of the show case 3 lowers, and a cooling effect can be increased.SELECTED DRAWING: Figure 1

Description

本発明は、冷凍装置に係り、特に、圧縮機、ガスクーラ、中間熱交換器および蒸発器から冷媒回路が構成され、高圧側が超臨界圧力となる冷凍装置に関する。   The present invention relates to a refrigeration apparatus, and more particularly, to a refrigeration apparatus in which a refrigerant circuit is configured by a compressor, a gas cooler, an intermediate heat exchanger, and an evaporator, and a high pressure side is a supercritical pressure.

従来から、例えば、スーパーマーケットなどの大型店舗においては、多くの冷凍ショーケースや冷蔵ショーケースが設置され、これらのショーケースを冷凍機で運転する冷凍装置が多く用いられている。   2. Description of the Related Art Conventionally, for example, in a large store such as a supermarket, many refrigeration showcases and refrigerated showcases are installed, and a refrigeration apparatus that operates these showcases with a refrigerator is often used.

このような冷凍装置として、従来、例えば、ガスクーラの下流側であって主絞り手段の上流側の冷媒回路に接続された圧力調整用絞り手段と、圧力調整用絞り手段の下流側であって主絞り手段の上流側の冷媒回路に接続された中間冷却器とを備え、制御手段により、圧力調整用絞り手段の開度を制御することにより、主絞り手段に流入する冷媒の圧力を所定の規定値に調整するようにした技術が開示されている（例えば、特許文献１参照）。   Conventionally, as such a refrigeration apparatus, for example, a pressure adjusting throttle means connected to a refrigerant circuit downstream of the gas cooler and upstream of the main throttle means, and a downstream side of the pressure adjusting throttle means. And an intermediate cooler connected to the refrigerant circuit upstream of the throttle means, and the control means controls the opening degree of the pressure adjusting throttle means to control the pressure of the refrigerant flowing into the main throttle means to a predetermined value. A technique for adjusting the value is disclosed (for example, see Patent Document 1).

ＷＯ２０１４／０６８９６７WO2014 / 068967

しかしながら、前記特許文献１に記載の技術においては、補助絞り手段の開度を最大にしても出口圧力が規定の圧力まで低下しない場合がある。特に、例えば、真夏の日中など過負荷条件では、出口圧力が臨界圧力である７．３ＭＰａよりも高い圧力となることがあり、その際は中間冷却器内で液化ができず、液化による冷却効果の増大が得られないので冷却性能が低下するという課題がある。
本発明は、前記した事情に鑑みてなされたものであり、過負荷条件時でも、冷凍機出口圧力を低減させることができ、中間冷却器における冷媒の液化を行い、冷凍能力を増大させることのできる冷凍装置を提供することを目的とするものである。 However, in the technique described in Patent Document 1, there are cases where the outlet pressure does not drop to a specified pressure even when the opening of the auxiliary throttle means is maximized. In particular, under an overload condition such as midsummer daytime, the outlet pressure may be higher than the critical pressure of 7.3 MPa. In that case, liquefaction cannot be performed in the intermediate cooler, and cooling due to liquefaction is caused. Since an increase in the effect cannot be obtained, there is a problem that the cooling performance is lowered.
The present invention has been made in view of the above-described circumstances, and can reduce the refrigerator outlet pressure even in an overload condition, liquefy the refrigerant in the intercooler, and increase the refrigeration capacity. It aims at providing the freezing apparatus which can be performed.

前記目的を達成するため、本発明に係る冷凍装置は、２段圧縮の圧縮機、インタクーラ、ガスクーラ、減圧電動弁、中間冷却器およびガス戻し用電動弁を備えた冷凍機と、主絞り手段および蒸発器とを備えたショーケースと、から構成される冷凍装置において、制御装置を備え、前記制御装置は、前記冷凍機の出口圧力が臨界圧力より高くなるとき、前記中間冷却器の上流側の前記減圧電動弁の開度を小さくするように制御することを特徴とする。   To achieve the above object, a refrigeration apparatus according to the present invention includes a two-stage compression compressor, an intercooler, a gas cooler, a decompression motor valve, an intermediate cooler, and a gas return motor valve, a main throttle means, A refrigeration apparatus comprising a showcase with an evaporator, and a control device, the control device is arranged on the upstream side of the intermediate cooler when the outlet pressure of the refrigerator becomes higher than a critical pressure. Control is performed to reduce the opening of the pressure-reducing motor-operated valve.

これにより、中間冷却器において、冷媒の気液分離により冷媒の液化が行われるので、冷凍機出口圧力を臨界圧力より低くすることができ、液冷媒をショーケースに送ることができるようになる。これにより、ショーケースの主絞り手段の入口側における冷媒の比エンタルピーが低下し、冷却効果を増大させることが可能となる。   Thereby, in the intercooler, since the refrigerant is liquefied by gas-liquid separation of the refrigerant, the refrigerator outlet pressure can be made lower than the critical pressure, and the liquid refrigerant can be sent to the showcase. As a result, the specific enthalpy of the refrigerant on the inlet side of the main throttle means of the showcase is reduced, and the cooling effect can be increased.

本発明によれば、冷凍機出口圧力を臨界圧力より低くすることができ、液冷媒をショーケースに送ることができる。これにより、ショーケースの主絞り手段の入口側における冷媒の比エンタルピーが低下し、冷却効果を増大させることが可能となる。   According to the present invention, the refrigerator outlet pressure can be made lower than the critical pressure, and the liquid refrigerant can be sent to the showcase. As a result, the specific enthalpy of the refrigerant on the inlet side of the main throttle means of the showcase is reduced, and the cooling effect can be increased.

本発明に係る冷凍装置の実施形態を示す冷凍サイクルの回路図The circuit diagram of the refrigerating cycle which shows the embodiment of the refrigerating device concerning the present invention. 本実施形態における制御装置を示すブロック図The block diagram which shows the control apparatus in this embodiment 本実施形態における制御動作を示すフローチャートFlow chart showing the control operation in the present embodiment 本発明による制御と従来技術の制御とによるｐ−ｈ線図Ph diagram with control according to the invention and control according to the prior art

第１の発明は、２段圧縮の圧縮機、インタクーラ、ガスクーラ、減圧電動弁、中間冷却器、ガス戻し用電動弁を備えた冷凍機と、主絞り手段および蒸発器とを備えたショーケースと、から構成される冷凍装置において、制御装置を備え、前記制御装置は、前記冷凍機の出口圧力が臨界圧力より高くなるとき、前記中間冷却器の上流側の前記減圧電動弁の開度を小さくするように制御することを特徴とする冷凍装置である。
これにより、中間冷却器において、冷凍機出口圧力を臨界圧力より低くすることができるので、冷媒の気液分離により冷媒の液化が行われ、液冷媒をショーケースに送ることができるようになる。これにより、ショーケースの主絞り手段の入口側における冷媒の比エンタルピーが低下し、冷却効果を増大させることが可能となる。 A first invention is a two-stage compression compressor, an intercooler, a gas cooler, a decompression motor operated valve, an intercooler, a refrigerator equipped with a gas return motor operated valve, a showcase equipped with a main throttle means and an evaporator, The control device includes a control device, and when the outlet pressure of the refrigerator becomes higher than a critical pressure, the control device reduces the opening degree of the pressure-reducing motor valve on the upstream side of the intermediate cooler. It is the freezing apparatus characterized by controlling so that it may do.
Thereby, in the intercooler, the refrigerator outlet pressure can be made lower than the critical pressure, so that the refrigerant is liquefied by gas-liquid separation of the refrigerant, and the liquid refrigerant can be sent to the showcase. As a result, the specific enthalpy of the refrigerant on the inlet side of the main throttle means of the showcase is reduced, and the cooling effect can be increased.

第２の発明は、制御装置は、圧縮機の吐出側の高圧圧力が、設計圧力との差が１ＭＰａ未満の時、圧縮機の回転量を低下させるように制御することを特徴とする冷凍装置である。
これによれば、圧縮機の回転量を低下させることで、冷凍機出口圧力を低下させることができる。この場合に、圧縮機の回転量を低下させることにより、冷媒の循環量が減少することになるが、冷媒の比エンタルピーを低下させることができるので、冷却効果が増大し、冷却能力を増大させることができる。 In a second aspect of the invention, the control device controls the high pressure pressure on the discharge side of the compressor to reduce the rotation amount of the compressor when the difference from the design pressure is less than 1 MPa. It is.
According to this, the refrigerator outlet pressure can be reduced by reducing the rotation amount of the compressor. In this case, reducing the amount of rotation of the compressor reduces the circulation amount of the refrigerant. However, since the specific enthalpy of the refrigerant can be reduced, the cooling effect is increased and the cooling capacity is increased. be able to.

第３の発明は、制御装置は、圧縮機の吐出側の高圧圧力が、設計圧力との差が１ＭＰａ未満の時、圧縮機の回転量を低下させて、圧縮機の吐出側の高圧圧力と設計圧力との差を確保した後、減圧電動弁の開度を小さくするように制御することを特徴とする冷凍装置である。
これによれば、圧縮機の吐出側の高圧圧力と設計圧力との差を確保した後、減圧電動弁の開度を小さくすることで、冷凍機出口圧力を低下させることができる。 According to a third aspect of the present invention, when the high-pressure pressure on the discharge side of the compressor has a difference from the design pressure of less than 1 MPa, the amount of rotation of the compressor is reduced, and the high-pressure pressure on the discharge side of the compressor After ensuring the difference from the design pressure, the refrigeration apparatus is controlled to reduce the opening of the pressure-reducing electric valve.
According to this, after ensuring the difference between the high pressure on the discharge side of the compressor and the design pressure, it is possible to reduce the refrigerator outlet pressure by reducing the opening of the pressure reducing electric valve.

以下、図面を参照して本発明の実施形態について図面を参照して説明する。
図１は、本発明に係る冷凍装置の実施形態を示す冷凍サイクルの回路図である。
図１に示すように、冷凍装置１は、冷媒を冷却する冷凍機２と、冷凍機２から送られる冷媒により冷却されるショーケース３とを備えている。ショーケース３は、例えば、コンビニエンスストアやスーパーマーケットなどの施設に設置され、陳列された冷蔵・冷凍商品を冷却するものである。
また、本実施形態においては、冷凍装置１は、高圧側の冷媒圧力（高圧圧力）がその臨界圧力以上（超臨界）となる二酸化炭素を冷媒として用いている。この二酸化炭素冷媒は、地球環境に優しく、可燃性および毒性などを考慮した自然冷媒である。 Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a circuit diagram of a refrigeration cycle showing an embodiment of a refrigeration apparatus according to the present invention.
As shown in FIG. 1, the refrigeration apparatus 1 includes a refrigerator 2 that cools the refrigerant, and a showcase 3 that is cooled by the refrigerant sent from the refrigerator 2. The showcase 3 is installed in a facility such as a convenience store or a supermarket, and cools the displayed refrigerated / frozen products.
Further, in the present embodiment, the refrigeration apparatus 1 uses carbon dioxide whose refrigerant pressure (high pressure) on the high pressure side is equal to or higher than its critical pressure (supercritical) as the refrigerant. This carbon dioxide refrigerant is a natural refrigerant that is friendly to the global environment and takes into consideration flammability and toxicity.

また、冷凍機２は、２段で圧縮動作される圧縮機１０を備えている。圧縮機１０には、冷凍用熱交換器１１が冷媒配管１２を介して接続されており、冷凍用熱交換器１１は、ガスクーラ１３と、インタクーラ１４と、オイルクーラ１５と、送風ファン１６とから構成されている。   The refrigerator 2 includes a compressor 10 that performs compression operation in two stages. A refrigeration heat exchanger 11 is connected to the compressor 10 via a refrigerant pipe 12. The refrigeration heat exchanger 11 includes a gas cooler 13, an intercooler 14, an oil cooler 15, and a blower fan 16. It is configured.

圧縮機１０には、１段目の圧縮機構における第１吸入口２０および第１吐出口２１が設けられており、２段目の圧縮機構における第２吸入口２２および第２吐出口２３が設けられている。
圧縮機１０の第２吐出口２３は、冷媒配管１２を介してオイルセパレータ２４に接続されており、オイルセパレータ２４は、冷媒配管１２を介してガスクーラ１３に接続されている。圧縮機１０の第２吐出口２３に接続される冷媒配管１２の中途部には、逆止弁２５が設けられている。 The compressor 10 is provided with a first suction port 20 and a first discharge port 21 in the first-stage compression mechanism, and a second suction port 22 and a second discharge port 23 in the second-stage compression mechanism. It has been.
The second discharge port 23 of the compressor 10 is connected to the oil separator 24 via the refrigerant pipe 12, and the oil separator 24 is connected to the gas cooler 13 via the refrigerant pipe 12. A check valve 25 is provided in the middle of the refrigerant pipe 12 connected to the second discharge port 23 of the compressor 10.

オイルセパレータ２４は、冷媒中のオイルを分離するものであり、オイルセパレータ２４は、オイル管２６を介してオイルクーラ１５の入口側に接続されており、オイルセパレータ２４により分離されたオイルをオイルクーラ１５に供給するように構成されている。また、オイルクーラ１５の出口側は、オイル管２６を介して圧縮機１０の中間段に接続されている。
オイル管２６の中途部には、三方弁からなるオイルサービスバルブ２７およびオイル調整電動弁２８が設けられている。 The oil separator 24 separates oil in the refrigerant, and the oil separator 24 is connected to the inlet side of the oil cooler 15 via the oil pipe 26, and the oil separated by the oil separator 24 is removed from the oil cooler. 15 is provided. Further, the outlet side of the oil cooler 15 is connected to an intermediate stage of the compressor 10 via an oil pipe 26.
An oil service valve 27 including a three-way valve and an oil adjusting electric valve 28 are provided in the middle of the oil pipe 26.

圧縮機１０の第１吸入口２０は、ショーケース３から送られる冷媒を吸入し、１段目の圧縮機構により、中間圧力に圧縮して第１吐出口２１から吐出するように構成されている。
また、圧縮機１０の第１吐出口２１は、冷媒配管１２を介してインタクーラ１４の入口側に接続されており、インタクーラ１４の出口側は、冷媒配管１２を介して圧縮機１０の第２吸入口２２に接続されている。 The first suction port 20 of the compressor 10 is configured to suck the refrigerant sent from the showcase 3, compress it to an intermediate pressure by the first-stage compression mechanism, and discharge the refrigerant from the first discharge port 21. .
The first discharge port 21 of the compressor 10 is connected to the inlet side of the intercooler 14 via the refrigerant pipe 12, and the outlet side of the intercooler 14 is connected to the second suction of the compressor 10 via the refrigerant pipe 12. Connected to the mouth 22.

そして、圧縮機１０の第１吐出口２１から中間圧に圧縮されて吐出された冷媒は、冷媒配管１２を介してインタクーラ１４に流入し、インタクーラ１４において、送風ファン１６を動作させることにより外気と熱交換して冷却され、圧縮機１０の第２吸入口２２に戻されるように構成されている。そして、圧縮機１０で２段目の圧縮機構により、必要な圧力に圧縮して第２吐出口２３から吐出され、オイルセパレータ２４を介してガスクーラ１３に送られるように構成されている。   Then, the refrigerant compressed and discharged from the first discharge port 21 of the compressor 10 to the intermediate pressure flows into the intercooler 14 through the refrigerant pipe 12, and the air blower 16 is operated in the intercooler 14, and the outside air is It is configured to be cooled by exchanging heat and returned to the second suction port 22 of the compressor 10. Then, the compressor 10 is configured to be compressed to a required pressure by the second stage compression mechanism and discharged from the second discharge port 23, and sent to the gas cooler 13 through the oil separator 24.

また、ガスクーラ１３は、圧縮機１０から送られた冷媒を送風ファン１６を動作させることにより外気と熱交換させて冷却するものであるが、二酸化炭素冷媒は、凝縮しないので、超臨界状態で高圧の気体のまま送られるようになっている。
また、ガスクーラ１３には、冷媒配管１２を介して中間冷却器３０が接続されており、この冷媒配管１２の中途部には、ガスクーラ１３から送られる冷媒を減圧するための減圧電動弁３１が設けられている。 The gas cooler 13 cools the refrigerant sent from the compressor 10 by exchanging heat with the outside air by operating the blower fan 16, but the carbon dioxide refrigerant does not condense, so it is high pressure in a supercritical state. The gas is sent as it is.
In addition, an intermediate cooler 30 is connected to the gas cooler 13 via the refrigerant pipe 12, and a pressure-reducing electric valve 31 for reducing the pressure of the refrigerant sent from the gas cooler 13 is provided in the middle of the refrigerant pipe 12. It has been.

中間冷却器３０の出口側の冷媒配管１２には、スプリット熱交換器３２が接続されている。
スプリット熱交換器３２の出口側の冷媒配管１２には、この冷媒配管１２から分岐する分岐配管３３が接続されており、分岐配管３３は、液戻し膨張弁３４を介してスプリット熱交換器３２に接続されている。冷媒配管１２と分岐配管３３とは、冷媒の流れる方向が対向流となるように配置されるものであり、冷媒配管１２を流れる冷媒と分岐配管３３を流れる冷媒とを効率よく熱交換させることができるように構成されている。
中間冷却器３０には、ガス戻し電動弁３５を介して冷媒戻し配管３６が接続されており、冷媒戻し配管３６は、分岐配管３３に接続されている。 A split heat exchanger 32 is connected to the refrigerant pipe 12 on the outlet side of the intermediate cooler 30.
A branch pipe 33 branched from the refrigerant pipe 12 is connected to the refrigerant pipe 12 on the outlet side of the split heat exchanger 32, and the branch pipe 33 is connected to the split heat exchanger 32 via a liquid return expansion valve 34. It is connected. The refrigerant pipe 12 and the branch pipe 33 are arranged so that the refrigerant flows in opposite directions, and the refrigerant flowing through the refrigerant pipe 12 and the refrigerant flowing through the branch pipe 33 can efficiently exchange heat. It is configured to be able to.
A refrigerant return pipe 36 is connected to the intercooler 30 via a gas return electric valve 35, and the refrigerant return pipe 36 is connected to a branch pipe 33.

スプリット熱交換器３２の出口側の冷媒配管１２には、ショーケース３の蒸発器４０に冷媒を送るための出口サービスバルブ３７が接続されている。一方、圧縮機１０の第１吸入口２０に接続される冷媒配管１２には、ショーケース３の蒸発器４０からの冷媒が戻るための入口サービスバルブ３８が接続されている。   An outlet service valve 37 for sending the refrigerant to the evaporator 40 of the showcase 3 is connected to the refrigerant pipe 12 on the outlet side of the split heat exchanger 32. On the other hand, an inlet service valve 38 for returning the refrigerant from the evaporator 40 of the showcase 3 is connected to the refrigerant pipe 12 connected to the first suction port 20 of the compressor 10.

スプリット熱交換器３２の出口側の分岐配管３３は、インタクーラ１４の出口側に接続されている。
そして、液戻し膨張弁３４は、スプリット熱交換器３２の出口側の高圧冷媒を減圧させて中間圧力レベルまで膨張させるものであり、スプリット熱交換器３２により冷媒配管１２を流れる高圧冷媒と分岐配管３３を流れる減圧された冷媒とを熱交換させて高圧冷媒を冷却するように構成されている。
スプリット熱交換器３２により熱交換した冷媒は、インタクーラ１４の出口側の冷媒と合流して第２吸入口２２から圧縮機１０に送られ、圧縮機１０から吐出される冷媒の温度の最適化を図るようになっている。 A branch pipe 33 on the outlet side of the split heat exchanger 32 is connected to the outlet side of the intercooler 14.
The liquid return expansion valve 34 decompresses the high-pressure refrigerant on the outlet side of the split heat exchanger 32 and expands it to an intermediate pressure level, and the high-pressure refrigerant and the branch pipe flowing through the refrigerant pipe 12 by the split heat exchanger 32. The high-pressure refrigerant is cooled by exchanging heat with the reduced-pressure refrigerant flowing through 33.
The refrigerant heat-exchanged by the split heat exchanger 32 joins the refrigerant on the outlet side of the intercooler 14 and is sent from the second suction port 22 to the compressor 10 to optimize the temperature of the refrigerant discharged from the compressor 10. It is designed to be illustrated.

また、出口サービスバルブ３７には、複数のショーケース３の蒸発器４０がそれぞれ主絞り手段４１を介して接続されており、蒸発器４０により冷媒配管１２から送られる冷媒と庫内の空気とを熱交換させ、各ショーケース３の庫内の冷却を行うように構成されている。蒸発器４０の出口側は、入口サービスバルブ３８に接続されている。   Further, the outlet service valve 37 is connected to the evaporators 40 of the plurality of showcases 3 via the main throttle means 41, respectively, and the refrigerant sent from the refrigerant pipe 12 by the evaporator 40 and the air in the warehouse are connected. Heat exchange is performed, and the interior of each showcase 3 is cooled. The outlet side of the evaporator 40 is connected to an inlet service valve 38.

また、圧縮機１０の吐出側には、圧縮機１０から吐出される冷媒圧力を検出する高圧圧力センサ５０が設けられ、圧縮機１０の吸入側には、圧縮機１０から吸入される冷媒圧力を検出する低圧圧力センサ５１が設けられている。また、インタクーラ１４の出口側と圧縮機１０の第２吸入口２２との間には、冷媒の中間圧力を検出する中間圧圧力センサ５２が設けられている。
さらに、本実施形態においては、中間冷却器３０とガス戻し電動弁３５との間には、冷凍機２からショーケース３に送られる冷媒圧力を検出する冷凍機出口圧力センサ５３が設けられている。 A high-pressure sensor 50 that detects the refrigerant pressure discharged from the compressor 10 is provided on the discharge side of the compressor 10, and the refrigerant pressure drawn from the compressor 10 is set on the suction side of the compressor 10. A low pressure sensor 51 for detection is provided. An intermediate pressure sensor 52 that detects the intermediate pressure of the refrigerant is provided between the outlet side of the intercooler 14 and the second suction port 22 of the compressor 10.
Further, in the present embodiment, a refrigerator outlet pressure sensor 53 that detects the refrigerant pressure sent from the refrigerator 2 to the showcase 3 is provided between the intercooler 30 and the gas return motor operated valve 35. .

また、冷媒配管１２の入口側には、ショーケース３から送られる冷媒温度を検出する冷凍機入口温度センサ５４が設けられ、冷媒配管１２の出口側には、ショーケース３に送られる冷媒温度を検出する冷凍機出口温度センサ５５が設けられている。
圧縮機１０の吐出側には、冷媒の吐出温度を検出する吐出温度センサ５６が設けられ、ガスクーラ１３の出口側には、ガスクーラ１３の出口における冷媒温度を検出するガスクーラ出口温度センサ５７が設けられている。
ガスクーラ１３の近傍には、外気温度を検出する外気温度センサ５８が設けられ、スプリット熱交換器３２の出口側には、スプリット熱交換器３２の出口における冷媒温度を検出するスプリット出口温度センサ５９が設けられている。 In addition, a refrigerator inlet temperature sensor 54 for detecting a refrigerant temperature sent from the showcase 3 is provided on the inlet side of the refrigerant pipe 12, and the refrigerant temperature sent to the showcase 3 is set on the outlet side of the refrigerant pipe 12. A refrigerator outlet temperature sensor 55 for detection is provided.
A discharge temperature sensor 56 that detects the refrigerant discharge temperature is provided on the discharge side of the compressor 10, and a gas cooler outlet temperature sensor 57 that detects the refrigerant temperature at the outlet of the gas cooler 13 is provided on the outlet side of the gas cooler 13. ing.
An outdoor air temperature sensor 58 that detects the outdoor air temperature is provided in the vicinity of the gas cooler 13, and a split outlet temperature sensor 59 that detects the refrigerant temperature at the outlet of the split heat exchanger 32 is provided on the outlet side of the split heat exchanger 32. Is provided.

次に、本実施形態の制御構成について説明する。
図２は、本実施形態における制御構成を示すブロック図である。
図２に示すように、本実施形態においては、冷凍機２は、各部を統括して制御する制御装置６０を備えている。 Next, the control configuration of this embodiment will be described.
FIG. 2 is a block diagram showing a control configuration in the present embodiment.
As shown in FIG. 2, in the present embodiment, the refrigerator 2 includes a control device 60 that controls each part in an integrated manner.

制御装置６０は、高圧圧力センサ５０、低圧圧力センサ５１、中間圧圧力センサ５２および冷凍機出口圧力センサ５３の検出値が入力されるように構成されている。また、制御装置６０は、冷媒吐出温度センサ５６、外気温度センサ５８、ガスクーラ出口温度センサ５７、冷凍機出口温度センサ５５、冷凍機入口温度センサ５４、スプリット出口温度センサ５９からの検出値が入力されるように構成されている。
制御装置６０は、これら各センサ５０〜５９からの検出値および運転設定条件に基づいて、圧縮機１０の駆動周波数、室外ファンの回転数、減圧電動弁３１、液戻し電動弁、ガス戻し電動弁３５の開度をそれぞれ制御するように構成されている。 The control device 60 is configured such that detection values of the high pressure sensor 50, the low pressure sensor 51, the intermediate pressure sensor 52, and the refrigerator outlet pressure sensor 53 are input. The control device 60 also receives detection values from the refrigerant discharge temperature sensor 56, the outside air temperature sensor 58, the gas cooler outlet temperature sensor 57, the refrigerator outlet temperature sensor 55, the refrigerator inlet temperature sensor 54, and the split outlet temperature sensor 59. It is comprised so that.
Based on the detection values from these sensors 50 to 59 and the operation setting conditions, the control device 60 drives the compressor 10, the rotational speed of the outdoor fan, the decompression electric valve 31, the liquid return electric valve, and the gas return electric valve. It is comprised so that the opening degree of 35 may be controlled, respectively.

また、本実施形態においては、制御装置６０は、冷凍機出口圧力センサ５３による冷媒の冷凍機出口圧力の検出値を入力し、冷凍機出口圧力が所定値より低いか否かを判断する。
一般に、二酸化炭素冷媒において、臨界圧力は、７．３ＭＰａであり、そのため、冷凍機出口圧力が７．３ＭＰａを超えると、中間冷却器３０において、冷媒の液化ができず、冷却性能が低下してしまう。 Moreover, in this embodiment, the control apparatus 60 inputs the detection value of the refrigerator outlet pressure of the refrigerant | coolant by the refrigerator outlet pressure sensor 53, and judges whether a refrigerator outlet pressure is lower than predetermined value.
Generally, in the carbon dioxide refrigerant, the critical pressure is 7.3 MPa. Therefore, if the outlet pressure of the refrigerator exceeds 7.3 MPa, the refrigerant cannot be liquefied in the intercooler 30 and the cooling performance is reduced. End up.

そのため、本実施形態においては、制御装置６０は、冷凍機出口圧力センサ５３による冷媒の冷凍機出口圧力が７．３ＭＰａに至らない所定値、例えば、７．２ＭＰａより低いか否かを判断する。なお、所定値は、７．２ＭＰａに限定されるものではなく、その他の値に任意に設定することが可能である。
そして、冷凍機出口圧力が７．２ＭＰａ以上であると判断した場合は、さらに、圧縮機１０の吐出側における冷媒の高圧圧力が所定値より低いか否かを判断する。 Therefore, in the present embodiment, the control device 60 determines whether or not the refrigerator outlet pressure of the refrigerant by the refrigerator outlet pressure sensor 53 is lower than a predetermined value that does not reach 7.3 MPa, for example, 7.2 MPa. The predetermined value is not limited to 7.2 MPa, and can be arbitrarily set to other values.
When it is determined that the refrigerator outlet pressure is 7.2 MPa or more, it is further determined whether or not the high pressure of the refrigerant on the discharge side of the compressor 10 is lower than a predetermined value.

圧縮機１０の吐出冷媒の設計圧力は、１２ＭＰａに設定されている。そのため、多少の余裕をみて、圧縮機１０の吐出冷媒の高圧圧力が、例えば、１１ＭＰａより低いか否かを判断し、吐出冷媒の高圧圧力が、１１ＭＰａより低ければ、減圧電動弁３１の回動を減少するように制御する。なお、所定値は、１１ＭＰａに限定されるものではなく、その他の値に任意に設定することが可能である。
一方、吐出冷媒の高圧圧力が、１１ＭＰａ以上であれば、圧縮機１０の回転数を低下するように制御する。
このように制御することにより、圧縮機１０の吐出冷媒の高圧圧力が、１１ＭＰａ以上となるまでは、減圧電動弁３１の開度を調整するように制御して冷凍機出口圧力が臨界圧力を超えないように制御し、これにより、必要以上に圧縮機１０の能力を低下させることがなく、冷凍機２の冷却性能を維持することが可能となる。 The design pressure of the refrigerant discharged from the compressor 10 is set to 12 MPa. Therefore, with some allowance, it is determined whether or not the high pressure pressure of the refrigerant discharged from the compressor 10 is lower than 11 MPa, for example, and if the high pressure pressure of the discharged refrigerant is lower than 11 MPa, the rotation of the decompression electric valve 31 is performed. Control to decrease. The predetermined value is not limited to 11 MPa and can be arbitrarily set to other values.
On the other hand, if the high-pressure pressure of the discharged refrigerant is 11 MPa or more, control is performed so as to reduce the rotational speed of the compressor 10.
By controlling in this way, until the high-pressure pressure of the refrigerant discharged from the compressor 10 becomes 11 MPa or more, control is performed so as to adjust the opening degree of the decompression electric valve 31, and the refrigerator outlet pressure exceeds the critical pressure. Thus, it is possible to maintain the cooling performance of the refrigerator 2 without reducing the capacity of the compressor 10 more than necessary.

そして、制御装置６０により、減圧電動弁３１または圧縮機１０の制御を行った場合に、冷凍機出口圧力センサ５３による冷媒の冷凍機出口圧力の検出値を入力し、冷凍機出口圧力が所定値より低いか否かを判断する。この場合の所定値は、例えば、７．２ＭＰａより低い６．８ＭＰａとされる。
制御装置６０は、冷凍機出口圧力が６．８ＭＰａより高い場合は、再度、７．２ＭＰａより低いか否かを判断するとともに、圧縮機１０の吐出冷媒の高圧圧力が１１ＭＰａより低いか否かを判断する。
その判断結果に基づいて、前述のように、減圧電動弁３１の開度または圧縮機１０の回転数を制御するように構成されている。 Then, when the controller 60 controls the pressure-reducing electric valve 31 or the compressor 10, the detected value of the refrigerant outlet pressure of the refrigerant by the refrigerator outlet pressure sensor 53 is input, and the refrigerator outlet pressure is a predetermined value. Determine if it is lower. The predetermined value in this case is, for example, 6.8 MPa lower than 7.2 MPa.
When the refrigerator outlet pressure is higher than 6.8 MPa, the control device 60 determines again whether it is lower than 7.2 MPa and determines whether the high-pressure pressure of the refrigerant discharged from the compressor 10 is lower than 11 MPa. to decide.
Based on the determination result, as described above, the opening degree of the pressure-reducing motor-operated valve 31 or the rotation speed of the compressor 10 is controlled.

次に、本実施形態の動作について説明する。
まず、圧縮機１０を動作させることにより、圧縮機１０の第１吸入口２０によりショーケース３から送られる冷媒を吸入し、この冷媒は、１段目の圧縮機構により、中間圧力に圧縮されて第１吐出口２１から吐出される。 Next, the operation of this embodiment will be described.
First, by operating the compressor 10, the refrigerant sent from the showcase 3 is sucked through the first suction port 20 of the compressor 10, and this refrigerant is compressed to an intermediate pressure by the first-stage compression mechanism. It is discharged from the first discharge port 21.

また、圧縮機１０の第１吐出口２１から吐出された冷媒は、冷媒配管１２を介してインタクーラ１４に流入する。このインタクーラ１４で送風ファン１６により外気と熱交換して冷却され、圧縮機１０の第２吸入口２２にそれぞれ戻される。
インタクーラ１４から戻された冷媒は、圧縮機１０で２段目の圧縮機構により必要な圧力に圧縮して第２吐出口２３から吐出され、オイルセパレータ２４を介してガスクーラ１３に送られる。 Further, the refrigerant discharged from the first discharge port 21 of the compressor 10 flows into the intercooler 14 through the refrigerant pipe 12. The intercooler 14 is cooled by exchanging heat with the outside air by the blower fan 16 and returned to the second suction port 22 of the compressor 10.
The refrigerant returned from the intercooler 14 is compressed by the compressor 10 to a required pressure by the second-stage compression mechanism, discharged from the second discharge port 23, and sent to the gas cooler 13 through the oil separator 24.

圧縮機１０から送られた冷媒は、ガスクーラ１３１５で送風ファン１６により外気と熱交換させて冷却して中間冷却器３０に送られる。
この冷媒は、中間冷却器３０で冷却された冷媒は、スプリット熱交換器３２で冷媒配管１２から分岐して液戻し膨張弁３４を介して減圧された冷媒と熱交換して冷却され、出口サービスバルブ３７を介してショーケース３に送られる。 The refrigerant sent from the compressor 10 is cooled by heat exchange with the outside air by the blower fan 16 by the gas cooler 1315 and sent to the intermediate cooler 30.
The refrigerant cooled by the intermediate cooler 30 is cooled by exchanging heat with the refrigerant branched from the refrigerant pipe 12 by the split heat exchanger 32 and depressurized via the liquid return expansion valve 34, and is then discharged from the outlet service. It is sent to the showcase 3 via the valve 37.

そして、ショーケース３に送られた冷媒は、主絞り手段４１３４により所定の圧力に減圧され、蒸発器４０において熱交換して、庫内を所定温度に冷却するようになっている。
蒸発器４０から流出した冷媒は、入口サービスバルブ３８および冷媒配管１２を介して圧縮機１０に戻される。 The refrigerant sent to the showcase 3 is depressurized to a predetermined pressure by the main throttle means 4134, heat exchange is performed in the evaporator 40, and the interior is cooled to a predetermined temperature.
The refrigerant flowing out of the evaporator 40 is returned to the compressor 10 via the inlet service valve 38 and the refrigerant pipe 12.

次に、本実施形態の制御動作について、図３に示すフローチャートを参照して説明する。
図３は、本実施形態の制御動作を示すフローチャートである。
図３に示すように、運転開始している状態で、制御装置６０は、冷凍機出口圧力センサ５３による冷媒の冷凍機出口圧力の検出値を入力し、冷凍機出口圧力が７．２ＭＰａより低いか否かを判断する（ＳＴ１）。冷凍機出口圧力が７．２ＭＰａより低いと判断した場合は（ＳＴ１：ＹＥＳ）、制御装置６０により、通常の制御を行う（ＳＴ２）。 Next, the control operation of this embodiment will be described with reference to the flowchart shown in FIG.
FIG. 3 is a flowchart showing the control operation of this embodiment.
As shown in FIG. 3, the control device 60 inputs the detected value of the refrigerant outlet pressure of the refrigerant by the refrigerator outlet pressure sensor 53 while the operation is started, and the refrigerator outlet pressure is lower than 7.2 MPa. Is determined (ST1). When it is determined that the refrigerator outlet pressure is lower than 7.2 MPa (ST1: YES), the control device 60 performs normal control (ST2).

冷凍機出口圧力が７．２ＭＰａ以上であると判断した場合は（ＳＴ１：ＮＯ）、制御装置６０は、圧縮機１０の吐出冷媒の高圧圧力が、１１ＭＰａより低いか否かを判断する（ＳＴ３）。そして、吐出冷媒の高圧圧力が、１１ＭＰａより低ければ（ＳＴ３：ＹＥＳ）、減圧電動弁３１の開度を減少するように制御する（ＳＴ４）。
一方、吐出冷媒の高圧圧力が、１１ＭＰａ以上であれば（ＳＴ３：ＮＯ）、制御装置６０は、圧縮機１０の回転数を低下するように制御する（ＳＴ５）。 When it is determined that the refrigerator outlet pressure is 7.2 MPa or more (ST1: NO), the control device 60 determines whether or not the high-pressure pressure of the refrigerant discharged from the compressor 10 is lower than 11 MPa (ST3). . If the high pressure of the discharged refrigerant is lower than 11 MPa (ST3: YES), control is performed so as to decrease the opening degree of the decompression electric valve 31 (ST4).
On the other hand, if the high-pressure pressure of the discharged refrigerant is 11 MPa or more (ST3: NO), control device 60 controls to reduce the rotational speed of compressor 10 (ST5).

そして、制御装置６０により、減圧電動弁３１または圧縮機１０の制御を行った後、冷凍機出口圧力センサ５３による冷媒の冷凍機出口圧力の検出値を入力し、冷凍機出口圧力が６．８ＭＰａより低いか否かを判断する（ＳＴ６）。
冷凍機出口圧力が６．８ＭＰａより低いと判断した場合は（ＳＴ６：ＹＥＳ）、制御装置６０により、通常の制御を行う（ＳＴ２）。 And after controlling the pressure-reduction motor valve 31 or the compressor 10 with the control apparatus 60, the detected value of the refrigerant | coolant freezer outlet pressure by the freezer outlet pressure sensor 53 is input, and freezer outlet pressure is 6.8 MPa. It is determined whether it is lower (ST6).
When it is determined that the refrigerator outlet pressure is lower than 6.8 MPa (ST6: YES), the control device 60 performs normal control (ST2).

一方、冷凍機出口圧力が６．８ＭＰａ以上であると判断した場合は（ＳＴ６：ＮＯ）、制御装置６０は、一定時間、減圧電動弁３１の開度および圧縮機１０の回転数を維持した状態で（ＳＴ７）、再度、冷凍機出口圧力センサ５３により、冷凍機出口圧力が７．２ＭＰａより低いか否かを判断する（ＳＴ１）。
制御装置６０は、判断結果に基づいて、前述のように、減圧電動弁３１の開度または圧縮機１０の回転数を制御する。これを冷凍機出口圧力が臨界圧力より低くなるまで、繰り返して行う。 On the other hand, when it is determined that the refrigerator outlet pressure is 6.8 MPa or more (ST6: NO), the control device 60 maintains the opening degree of the pressure reducing electric valve 31 and the rotation speed of the compressor 10 for a certain period of time. (ST7), the refrigerator outlet pressure sensor 53 again determines whether the refrigerator outlet pressure is lower than 7.2 MPa (ST1).
Based on the determination result, the control device 60 controls the opening degree of the pressure-reducing motor-operated valve 31 or the rotational speed of the compressor 10 as described above. This is repeated until the refrigerator outlet pressure is lower than the critical pressure.

以上説明したように、本実施形態によれば、制御装置６０は、冷凍機２の出口圧力が臨界圧力より高くなるとき、中間冷却器３０の上流側の減圧電動弁３１の開度を小さくするように制御する。
これによれば、中間冷却器３０において、冷媒の気液分離により冷媒の液化が行われるので、冷凍機出口圧力を臨界圧力より低くすることができ、液冷媒をショーケース３に送ることができるようになる。これにより、ショーケース３の主絞り手段４１の入口側における冷媒の比エンタルピーが低下し、冷却効果を増大させることが可能となる。 As described above, according to this embodiment, when the outlet pressure of the refrigerator 2 becomes higher than the critical pressure, the control device 60 decreases the opening degree of the pressure reducing electric valve 31 on the upstream side of the intercooler 30. To control.
According to this, since the refrigerant is liquefied by the gas-liquid separation of the refrigerant in the intercooler 30, the refrigerator outlet pressure can be made lower than the critical pressure, and the liquid refrigerant can be sent to the showcase 3. It becomes like this. As a result, the specific enthalpy of the refrigerant on the inlet side of the main throttle means 41 of the showcase 3 is reduced, and the cooling effect can be increased.

図４は本発明による制御と従来の制御とによるｐ−ｈ線図である。
図４に示すように、従来の制御により冷凍機出口圧力が７．３ＭＰａより高い場合、気液分離が行われず、比エンタルピーを低下させることができない。
これに対して、本発明による制御においては、冷凍機出口圧力を７．３ＭＰａより低くすることで、中間冷却器３０で気液分離できるようになり、冷媒が液化したことで、主絞り手段４１の入口側での冷媒の比エンタルピーを低下させることが可能となる。これにより、冷却効果を増大させることができる。 FIG. 4 is a ph diagram based on the control according to the present invention and the conventional control.
As shown in FIG. 4, when the refrigerator outlet pressure is higher than 7.3 MPa by conventional control, gas-liquid separation is not performed, and the specific enthalpy cannot be reduced.
On the other hand, in the control according to the present invention, by making the refrigerator outlet pressure lower than 7.3 MPa, gas-liquid separation can be performed by the intercooler 30, and the refrigerant is liquefied. It becomes possible to reduce the specific enthalpy of the refrigerant on the inlet side. Thereby, the cooling effect can be increased.

また、本実施形態においては、制御装置６０は、圧縮機１０の吐出側の高圧圧力が、設計圧力との差が１ＭＰａ未満の時、圧縮機１０の回転量を低下させるように制御する。
これによれば、圧縮機１０の回転量を低下させることで、冷凍機出口圧力を低下させることができる。
この場合に、圧縮機１０の回転量を低下させることにより、冷媒の循環量が減少することになるが、冷媒の比エンタルピーを低下させることができるので、冷却効果が増大し、冷却能力を増大させることができる。 In the present embodiment, the control device 60 controls the amount of rotation of the compressor 10 to be reduced when the high-pressure pressure on the discharge side of the compressor 10 is less than 1 MPa.
According to this, the refrigerator outlet pressure can be reduced by reducing the rotation amount of the compressor 10.
In this case, reducing the rotation amount of the compressor 10 reduces the circulation amount of the refrigerant. However, since the specific enthalpy of the refrigerant can be reduced, the cooling effect is increased and the cooling capacity is increased. Can be made.

本実施形態においては、制御装置６０は、圧縮機１０の吐出側の高圧圧力が、設計圧力との差が１ＭＰａ未満の時、圧縮機１０の回転量を低下させて、圧縮機１０の吐出側の高圧圧力と設計圧力との差を確保した後、減圧電動弁３１の開度を小さくするように制御する。
これによれば、圧縮機１０の吐出側の高圧圧力と設計圧力との差を確保した後、減圧電動弁３１の開度を小さくすることで、冷凍機出口圧力を低下させることができる。 In the present embodiment, the control device 60 reduces the rotation amount of the compressor 10 when the difference between the high pressure on the discharge side of the compressor 10 and the design pressure is less than 1 MPa, and the discharge side of the compressor 10 After ensuring the difference between the high pressure and the design pressure, control is performed to reduce the opening degree of the pressure-reducing motor-operated valve 31.
According to this, after ensuring the difference between the high-pressure pressure on the discharge side of the compressor 10 and the design pressure, the refrigerator outlet pressure can be reduced by reducing the opening of the pressure-reducing electric valve 31.

なお、本発明は前記実施形態に限定されるものではなく、本発明の趣旨を逸脱しない範囲で、種々変更が可能である。   In addition, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the meaning of this invention.

１ 冷凍装置
２ 冷凍機
３ ショーケース
１０ 圧縮機
１１ 冷凍用熱交換器
１３ ガスクーラ
１４ インタクーラ
１５ オイルクーラ
１６ 送風ファン
２６ オイル管
２８ オイル調整電動弁
３０ 中間熱交換器
３１ 減圧電動弁
３２ スプリット熱交換器
３３ 分岐配管
３４ 液戻し膨張弁
３５ ガス戻し電動弁
４０ 蒸発器
４１ 主絞り手段
５０ 高圧圧力センサ
５１ 低圧圧力センサ
５２ 中間圧圧力センサ
５３ 冷凍機出口圧力センサ
５４ 冷凍機入口温度センサ
５５ 冷凍機出口温度センサ
５６ 吐出温度センサ
５７ ガスクーラ出口温度センサ
５８ 外気温度センサ
５９ スプリット出口温度センサ
６０ 制御装置 DESCRIPTION OF SYMBOLS 1 Refrigeration apparatus 2 Refrigerator 3 Showcase 10 Compressor 11 Refrigeration heat exchanger 13 Gas cooler 14 Intercooler 15 Oil cooler 16 Blower fan 26 Oil pipe 28 Oil adjustment electric valve 30 Intermediate heat exchanger 31 Pressure reduction motor valve 32 Split heat exchanger 33 branch piping 34 liquid return expansion valve 35 gas return motor operated valve 40 evaporator 41 main throttle means 50 high pressure sensor 51 low pressure sensor 52 intermediate pressure sensor 53 refrigerator outlet pressure sensor 54 refrigerator inlet temperature sensor 55 refrigerator outlet temperature Sensor 56 Discharge temperature sensor 57 Gas cooler outlet temperature sensor 58 Outside air temperature sensor 59 Split outlet temperature sensor 60 Control device

Claims (3)

２段圧縮の圧縮機、インタクーラ、ガスクーラ、減圧電動弁、中間冷却器およびガス戻し用電動弁を備えた冷凍機と、主絞り手段および蒸発器とを備えたショーケースと、から構成される冷凍装置において、
制御装置を備え、前記制御装置は、前記冷凍機の出口圧力が臨界圧力より高くなるとき、前記中間冷却器の上流側の前記減圧電動弁の開度を小さくするように制御することを特徴とする冷凍装置。 Refrigeration comprising a two-stage compression compressor, an intercooler, a gas cooler, a decompression electric valve, an intercooler, and a gas return electric valve, and a showcase provided with a main throttle means and an evaporator In the device
A control device, wherein the control device controls the opening of the pressure-reducing motor valve on the upstream side of the intermediate cooler when the outlet pressure of the refrigerator becomes higher than a critical pressure. Refrigeration equipment. 前記制御装置は、前記圧縮機の吐出側の高圧圧力が、設計圧力との差が１ＭＰａ未満の時、前記圧縮機の回転量を低下させるように制御することを特徴とする請求項１に記載の冷凍装置。   2. The control device according to claim 1, wherein the high pressure pressure on the discharge side of the compressor controls the amount of rotation of the compressor to be reduced when a difference from a design pressure is less than 1 MPa. Refrigeration equipment. 前記制御装置は、前記圧縮機の吐出側の高圧圧力が、設計圧力との差が１ＭＰａ未満の時、前記圧縮機の回転量を低下させて、圧縮機の吐出側の高圧圧力と設計圧力との差を確保した後、前記減圧電動弁の開度を小さくするように制御することを特徴とする請求項２に記載の冷凍装置。   When the difference between the high pressure pressure on the discharge side of the compressor and the design pressure is less than 1 MPa, the control device reduces the amount of rotation of the compressor so that the high pressure pressure on the discharge side of the compressor and the design pressure The refrigeration apparatus according to claim 2, wherein after the difference is secured, control is performed to reduce the opening of the pressure-reducing motor-operated valve.
JP2016061616A 2016-03-25 2016-03-25 Refrigerating device Pending JP2017172923A (en)

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CN201610741304.2A CN107228520A (en) 2016-03-25 2016-08-26 Refrigerating plant
US15/249,944 US20170276416A1 (en) 2016-03-25 2016-08-29 Refrigeration apparatus

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2020091063A (en) * 2018-12-05 2020-06-11 パナソニックＩｐマネジメント株式会社 Refrigeration machine
WO2022244619A1 (en) 2021-05-19 2022-11-24 パナソニックＩｐマネジメント株式会社 Cooling unit using two-stage compressor

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001289537A (en) * 2000-04-10 2001-10-19 Mitsubishi Heavy Ind Ltd Pressure control valve
CN100538224C (en) * 2007-10-31 2009-09-09 蓬莱京鲁渔业有限公司 Ultra low temperature cool house
WO2009157320A1 (en) * 2008-06-24 2009-12-30 三菱電機株式会社 Refrigerating cycle apparatus, and air conditioning apparatus
DK2339265T3 (en) * 2009-12-25 2018-05-28 Sanyo Electric Co Cooling device
EP2339266B1 (en) * 2009-12-25 2018-03-28 Sanyo Electric Co., Ltd. Refrigerating apparatus
JP2013164250A (en) * 2012-02-13 2013-08-22 Panasonic Corp Refrigerating apparatus
JP2013257081A (en) * 2012-06-13 2013-12-26 Calsonic Kansei Corp Gas/liquid separating heat exchanger and air conditioner
CN104755858A (en) * 2012-10-31 2015-07-01 松下知识产权经营株式会社 Refrigeration device

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2020091063A (en) * 2018-12-05 2020-06-11 パナソニックＩｐマネジメント株式会社 Refrigeration machine
WO2022244619A1 (en) 2021-05-19 2022-11-24 パナソニックＩｐマネジメント株式会社 Cooling unit using two-stage compressor

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