JP2011179783A

JP2011179783A - Refrigerating device

Info

Publication number: JP2011179783A
Application number: JP2010046493A
Authority: JP
Inventors: Koji Ito; 浩二伊藤; Mitsuru Komatsu; 満小松; Fumihiko Sugiyama; 文彦杉山
Original assignee: Hitachi Appliances Inc
Current assignee: Hitachi Appliances Inc
Priority date: 2010-03-03
Filing date: 2010-03-03
Publication date: 2011-09-15
Anticipated expiration: 2030-03-03
Also published as: JP5235925B2

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a refrigerating device capable of enhancing efficiency, improving reliability and reducing cost. <P>SOLUTION: The refrigerating device is constituted by interconnecting a compressor 1, a four-way valve 5, a heat source side heat exchanger 2, an expansion device 3 and a use side heat exchanger 4 by refrigerant piping. A supercooling heat exchanger 10 is provided between the heat source side heat exchanger 2 and the expansion device 3. The refrigerating device includes an injection circuit 21 branched from the refrigerant piping between the heat source side heat exchanger 2 and the expansion device 3, made to pass through the supercooling heat exchanger 10 and then, connected to an intermediate pressure part of the compressor 1. The injection circuit 21 includes a solenoid valve 11, a check valve 12, an electronic expansion valve 15 and a capillary tube 16. The refrigerating device further includes a bypass circuit branched from the refrigerant piping between the expansion device 3 and the use side heat exchanger 4 and connected to a portion between the check valve 12 and the electronic expansion valve 15 in the injection circuit 21. The bypass circuit also includes a solenoid valve 12 and a check valve 14. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

本発明は冷凍装置に関し、特に、冷暖房用や産業用の冷却及び加熱用に使用されるものに関する。 The present invention relates to a refrigeration apparatus, and more particularly to an apparatus used for cooling and heating for air conditioning and industrial use.

従来の冷凍装置としては、例えば特許文献１に記載のものがある。この引用文献１に記載された冷凍装置では、冷却運転時に、過冷却器で熱交換したガス冷媒を圧縮機中間圧力ポートへ戻すエコノマイザ回路と、液冷媒を膨張させて直接圧縮機の中間圧力ポートへ戻す液インジェクション回路を備えている。前記エコノマイザ回路は冷凍能力を調整するために用いられ、前記液インジェクション回路は圧縮機の温度上昇を防止するために用いられている。 As a conventional refrigeration apparatus, there is one described in Patent Document 1, for example. In the refrigerating apparatus described in the cited document 1, an economizer circuit for returning the gas refrigerant heat-exchanged by the supercooler to the compressor intermediate pressure port during the cooling operation, and an intermediate pressure port of the compressor directly by expanding the liquid refrigerant It has a liquid injection circuit to return to the back. The economizer circuit is used to adjust the refrigerating capacity, and the liquid injection circuit is used to prevent the temperature of the compressor from rising.

特開２００９−１０９０６５号公報JP 2009-109065 A

上記特許文献１に記載の冷凍装置では、エコノマイザ回路と液インジェクション回路の２系統を備えているため、部品点数が多くなり、原価が高くなるという課題があった。また、特許文献１に記載のものにおいて、四方弁を設けて、暖房或いは加熱運転も可能な構成とした場合、暖房或いは加熱運転時には、冷却運転時の過冷却器、膨張弁等をそのまま使用できず、加熱運転用に過冷却器、膨張弁を追加しなければならないという課題がある。 Since the refrigeration apparatus described in Patent Document 1 includes two systems, an economizer circuit and a liquid injection circuit, there is a problem that the number of parts increases and the cost increases. Moreover, in the thing of patent document 1, when a four-way valve is provided and it is set as the structure which can also perform heating or heating operation, the subcooler at the time of cooling operation, an expansion valve, etc. can be used as it is at the time of heating or heating operation. However, there is a problem that a supercooler and an expansion valve must be added for heating operation.

本発明の目的は、高効率化や信頼性向上を図れると共に原価低減も図れる冷凍装置を得ることにある。 An object of the present invention is to obtain a refrigeration apparatus capable of improving efficiency and improving reliability and reducing cost.

上記目的を達成するため、本発明は、圧縮機、四方弁、熱源側熱交換器、膨張装置及び利用側熱交換器が冷媒配管で接続された冷凍装置において、前記熱源側熱交換器と前記膨張装置の間に設けられた過冷却熱交換器と、前記熱源側熱交換器と前記膨張装置との間の前記冷媒配管から分岐され前記過冷却熱交換器を通過後、前記圧縮機の中間圧力部に接続されるインジェクション回路と、このインジェクション回路の前記過冷却熱交換器上流側に、上流側から順に設けられた開閉弁及び減圧手段と、前記膨張装置と前記利用側熱交換器との間の前記冷媒配管から分岐され、前記インジェクション回路の前記開閉弁と減圧手段との間に接続されるバイパス回路と、このバイパス回路に設けられた開閉弁とを備えることを特徴とする。 In order to achieve the above object, the present invention provides a refrigeration apparatus in which a compressor, a four-way valve, a heat source side heat exchanger, an expansion device, and a use side heat exchanger are connected by a refrigerant pipe, the heat source side heat exchanger and the A subcooling heat exchanger provided between the expansion devices, and the refrigerant pipe between the heat source side heat exchanger and the expansion device, and after passing through the supercooling heat exchanger, the middle of the compressor An injection circuit connected to the pressure unit, an on-off valve and a pressure reducing means provided in order from the upstream side on the upstream side of the supercooling heat exchanger of the injection circuit, the expansion device, and the use side heat exchanger And a bypass circuit that is branched from the refrigerant pipe in between and connected between the on-off valve of the injection circuit and the pressure-reducing means, and an on-off valve provided in the bypass circuit.

本発明の他の特徴は、圧縮機、四方弁、熱源側熱交換器、膨張装置及び利用側熱交換器が冷媒配管で接続された冷凍装置において、前記熱源側熱交換器と前記膨張装置の間に設けられた過冷却熱交換器と、前記熱源側熱交換器と前記膨張装置との間の前記冷媒配管から分岐され前記過冷却熱交換器を通過後、前記圧縮機の中間圧力部に接続されるインジェクション回路と、このインジェクション回路の前記過冷却熱交換器上流側に、上流側から順に設けられた開閉弁、電磁弁及びキャピラリチューブと、前記膨張装置と前記利用側熱交換器との間の前記冷媒配管から分岐され、前記インジェクション回路の前記開閉弁と前記電磁弁との間に接続されるバイパス回路と、このバイパス回路に設けられた開閉弁とを備えることにある。 Another feature of the present invention is a refrigeration apparatus in which a compressor, a four-way valve, a heat source side heat exchanger, an expansion device, and a use side heat exchanger are connected by a refrigerant pipe, the heat source side heat exchanger and the expansion device A subcooling heat exchanger provided in between, the refrigerant pipe between the heat source side heat exchanger and the expansion device, and after passing through the supercooling heat exchanger, to the intermediate pressure portion of the compressor An injection circuit to be connected; an on-off valve, a solenoid valve, and a capillary tube provided in this order from the upstream side to the upstream side of the supercooling heat exchanger of the injection circuit; and the expansion device and the use side heat exchanger It is provided with a bypass circuit branched from the refrigerant pipe in between and connected between the on-off valve and the solenoid valve of the injection circuit, and an on-off valve provided in the bypass circuit.

ここで、前記インジェクション回路に設けられた前記電磁弁とキャピラリチューブの組を並列に複数組配置した構成にするとインジェクション回路の流量調整が可能となる。また、並列に複数組配置された前記キャピラリチューブはそれぞれ異なる流路抵抗となるように、異なるサイズのものにするとインジェクション回路の流量をより細かく調整することが可能となる。 Here, if a plurality of sets of the solenoid valve and the capillary tube provided in the injection circuit are arranged in parallel, the flow rate of the injection circuit can be adjusted. Further, if the capillary tubes arranged in parallel are of different sizes so as to have different flow path resistances, the flow rate of the injection circuit can be finely adjusted.

本発明の更に他の特徴は、複数台の圧縮機、四方弁、熱源側熱交換器、膨張装置及び利用側熱交換器が冷媒配管で接続された冷凍装置において、前記熱源側熱交換器と前記膨張装置の間に設けられた過冷却熱交換器と、前記熱源側熱交換器と前記膨張装置との間の前記冷媒配管から分岐され前記過冷却熱交換器を通過後、前記各圧縮機の中間圧力部に接続されるインジェクション回路と、このインジェクション回路の前記過冷却熱交換器上流側に、上流側から順に設けられた開閉弁及び減圧手段と、前記膨張装置と前記利用側熱交換器との間の前記冷媒配管から分岐され、前記インジェクション回路の前記開閉弁と減圧手段との間に接続されるバイパス回路と、このバイパス回路に設けられた開閉弁とを備えることにある。 Still another feature of the present invention is a refrigeration apparatus in which a plurality of compressors, four-way valves, a heat source side heat exchanger, an expansion device, and a use side heat exchanger are connected by a refrigerant pipe, and the heat source side heat exchanger and The subcooling heat exchanger provided between the expansion devices, and the compressors after branching from the refrigerant pipe between the heat source side heat exchanger and the expansion device and passing through the supercooling heat exchanger. An injection circuit connected to the intermediate pressure section, an on-off valve and a pressure reducing means provided in order from the upstream side on the upstream side of the supercooling heat exchanger of the injection circuit, the expansion device, and the use side heat exchanger A bypass circuit that is branched from the refrigerant pipe between the injection circuit and connected between the on-off valve of the injection circuit and the pressure reducing means, and an on-off valve provided in the bypass circuit.

ここで、前記過冷却熱交換器は並列に複数台設けられ、主流となる前記冷媒配管を分岐させてそれぞれの過冷却熱交換器の主流側となる１次側流路に接続させ、前記インジェクション回路も前記開閉弁の下流側から複数に分岐され、これら複数に分岐されたそれぞれのインジェクション回路は複数台設けられた前記過冷却熱交換器の２次側流路に接続され、分岐された前記各インジェクション回路の過冷却熱交換器上流側に前記減圧手段が設けられ、この減圧手段は電子膨張弁、または電子膨張弁とキャピラリチューブで構成されていることが好ましい。 Here, a plurality of the supercooling heat exchangers are provided in parallel, and the refrigerant pipe which is the mainstream is branched and connected to the primary flow path which is the mainstream side of each supercooling heat exchanger, and the injection The circuit is also branched into a plurality from the downstream side of the on-off valve, and each of the plurality of branched injection circuits is connected to a secondary side flow path of the subcooling heat exchanger provided in a plurality, and branched. The decompression means is provided upstream of the subcooling heat exchanger of each injection circuit, and the decompression means is preferably composed of an electronic expansion valve or an electronic expansion valve and a capillary tube.

前記過冷却熱交換器は１次側流路と２次側流路を備え、前記１次側流路は主流となる前記冷媒配管に接続され、前記２次側流路は前記インジェクション回路に接続され、１次側流路を流れる冷媒と２次側流路を流れる冷媒が互いに熱交換される構成にすると良い。 The supercooling heat exchanger includes a primary flow path and a secondary flow path, the primary flow path is connected to the main refrigerant pipe, and the secondary flow path is connected to the injection circuit. The refrigerant flowing through the primary channel and the refrigerant flowing through the secondary channel may be configured to exchange heat with each other.

また、前記インジェクション回路及びバイパス回路に設けられた開閉弁は電磁弁であり、前記バイパス回路の前記電磁弁の下流側には逆止弁が設けられ、更に前記インジェクション回路の前記電磁弁と前記減圧手段との間にも逆止弁が設けられ、前記バイパス回路は前記インジェクション回路の前記逆止弁と減圧手段との間に接続される構成にすることが好ましい。 The on-off valve provided in the injection circuit and the bypass circuit is a solenoid valve, a check valve is provided downstream of the solenoid valve in the bypass circuit, and the solenoid valve and the pressure reducing valve in the injection circuit are further provided. It is preferable that a check valve be provided between the check circuit and the bypass circuit be connected between the check valve of the injection circuit and the pressure reducing means.

前記インジェクション回路に設けられた前記減圧手段は、電子膨張弁、キャピラリチューブ、又は電子膨張弁とキャピラリチューブの何れかにより構成することができる。
なお、前記インジェクション回路は、前記熱源側熱交換器と前記膨張装置の間の冷媒配管ならどこから分岐させても可能であるが、前記過冷却熱交換器と前記膨張装置との間の前記冷媒配管から分岐させて、前記過冷却熱交換器を通過後前記圧縮機の中間圧力部に接続される構成とすることが好ましい。 The decompression means provided in the injection circuit can be constituted by either an electronic expansion valve, a capillary tube, or an electronic expansion valve and a capillary tube.
The injection circuit may be branched from any refrigerant pipe between the heat source side heat exchanger and the expansion device, but the refrigerant pipe between the supercooling heat exchanger and the expansion device. It is preferable to make it the structure branched from and connecting to the intermediate pressure part of the said compressor after passing the said supercooling heat exchanger.

本発明によれば、冷却運転時には、圧縮機の吐出量を増加させずに能力上昇させることができ、ＣＯＰ向上も図れる。また、部品点数を大幅に増加させる必要がないので、原価低減を図れる効果もある。加熱運転時には、過冷却器で過冷却を取らずに湿り冷媒を圧縮機の中間圧力部に液インジェクションすることが可能となるので、加熱能力及びＣＯＰを低下させることなく圧縮機の信頼性向上を図ることができる効果が得られる。 According to the present invention, during the cooling operation, the capacity can be increased without increasing the discharge amount of the compressor, and the COP can be improved. In addition, since there is no need to increase the number of parts significantly, there is an effect that the cost can be reduced. During heating operation, it becomes possible to liquid-inject the wet refrigerant into the intermediate pressure part of the compressor without taking overcooling with the supercooler, so that the reliability of the compressor can be improved without lowering the heating capacity and COP. The effect which can be aimed at is acquired.

更に、インジェクション回路の流量を制御できる構成とすることにより、インジェクション回路をエコノマイザとして作用させて冷却能力増加させたまま、吐出ガス温度を連続的に制御することも可能となり、信頼性向上及び容量制御の高精度化も図ることができる効果が得られる。 Furthermore, by adopting a configuration that can control the flow rate of the injection circuit, it is possible to control the discharge gas temperature continuously while increasing the cooling capacity by operating the injection circuit as an economizer, improving reliability and capacity control. Thus, an effect can be obtained that can improve accuracy.

本発明の冷凍装置の実施例１を示す冷凍サイクル系統図。The refrigeration cycle system | strain diagram which shows Example 1 of the freezing apparatus of this invention. 本発明の実施例１における冷却運転時のモリエル線図。The Mollier diagram at the time of the cooling operation in Example 1 of this invention. 本発明の実施例１における加熱運転時のモリエル線図。The Mollier diagram at the time of the heating operation in Example 1 of this invention. 本発明の冷凍装置の実施例２を示す冷凍サイクル系統図。The refrigeration cycle system | strain diagram which shows Example 2 of the freezing apparatus of this invention. 本発明の冷凍装置の実施例３を示す冷凍サイクル系統図。The refrigeration cycle system | strain diagram which shows Example 3 of the refrigeration apparatus of this invention.

以下、本発明の実施例を図面に基づき説明する。 Embodiments of the present invention will be described below with reference to the drawings.

本発明の冷凍装置の実施例１を図１〜図３により説明する。
図１は冷暖房用や産業用の冷却及び加熱用に使用されるヒートポンプ式の冷凍装置を示す冷凍サイクル系統図である。 A first embodiment of the refrigeration apparatus of the present invention will be described with reference to FIGS.
FIG. 1 is a refrigeration cycle system diagram showing a heat pump type refrigeration apparatus used for air conditioning and industrial cooling and heating.

冷凍装置は、圧縮機１、四方弁５、熱源側熱交換器２、膨張装置３、利用側熱交換器４などが順次冷媒配管（主流となる冷媒配管で主冷媒配管ともいう）で接続されて構成されている。６は前記膨張装置３と利用側熱交換器４との間の冷媒配管に接続された冷媒量調節器、７は圧縮機１の吸込側に設けられたアキュームレータである。１０は前記熱源側熱交換器２と前記膨張装置３との間に設けられた過冷却熱交換器、２１は前記過冷却熱交換器１０と前記膨張装置３との間の冷媒配管から分岐され前記過冷却熱交換器を通過後、前記圧縮機１の中間圧力部に接続されたインジェクション回路である。このインジェクション回路２１の冷媒配管からの分岐部２１ａと前記過冷却熱交換器１０との間には上流側から順に冷却用電磁弁（開閉弁）１１、冷却用逆止弁１２、電子膨張弁（流量調整手段または減圧手段）１５、キャピラリチューブ（減圧手段）１６が設けられている。２２は前記膨張装置３と前記利用側熱交換器４との間の冷媒配管から分岐し、前記インジェクション回路２１の冷却用逆止弁１２と電子膨張弁１５との間に接続されるバイパス回路で、このバイパス回路２２には加熱用電磁弁（開閉弁）１３と加熱用逆止弁１４が設けられている。 In the refrigeration apparatus, the compressor 1, the four-way valve 5, the heat source side heat exchanger 2, the expansion device 3, the use side heat exchanger 4 and the like are sequentially connected by refrigerant pipes (main refrigerant pipes and also called main refrigerant pipes). Configured. 6 is a refrigerant quantity regulator connected to a refrigerant pipe between the expansion device 3 and the use side heat exchanger 4, and 7 is an accumulator provided on the suction side of the compressor 1. 10 is a supercooling heat exchanger provided between the heat source side heat exchanger 2 and the expansion device 3, and 21 is branched from a refrigerant pipe between the supercooling heat exchanger 10 and the expansion device 3. It is an injection circuit connected to the intermediate pressure part of the compressor 1 after passing through the supercooling heat exchanger. Between the branch portion 21a from the refrigerant pipe of the injection circuit 21 and the supercooling heat exchanger 10, a cooling solenoid valve (open / close valve) 11, a cooling check valve 12, an electronic expansion valve ( A flow rate adjusting means or pressure reducing means) 15 and a capillary tube (pressure reducing means) 16 are provided. A bypass circuit 22 branches from the refrigerant pipe between the expansion device 3 and the use side heat exchanger 4 and is connected between the cooling check valve 12 and the electronic expansion valve 15 of the injection circuit 21. The bypass circuit 22 is provided with a heating electromagnetic valve (open / close valve) 13 and a heating check valve 14.

なお、８ａ，８ｂ，８ｃは主冷媒配管に設けられたストレーナで、ストレーナ８ａは前記アキュームレータ７と圧縮機の間に、ストレーナ８ｂは前記バイパス回路２２の分岐部２２ａと前記冷媒量調節器６との間の主冷媒配管に、ストレーナ８ｃは前記インジェクション回路２１の分岐部２１ａと前記過冷却熱交換器１０との間の主冷媒配管にそれぞれ設けられている。９は圧縮機吐出側に設けられた主回路逆止弁である。前記圧縮機１は、圧縮機の中間圧力部にインジェクション可能なポートを有するスクロール圧縮機、ロータリー圧縮機、スクリュー圧縮機等で構成されている。 8a, 8b, and 8c are strainers provided in the main refrigerant pipe. The strainer 8a is provided between the accumulator 7 and the compressor, and the strainer 8b is provided between the branch portion 22a of the bypass circuit 22 and the refrigerant amount adjuster 6. The strainer 8c is provided in the main refrigerant pipe between the branch portion 21a of the injection circuit 21 and the supercooling heat exchanger 10, respectively. 9 is a main circuit check valve provided on the discharge side of the compressor. The compressor 1 is composed of a scroll compressor, a rotary compressor, a screw compressor, and the like having a port that can be injected into an intermediate pressure portion of the compressor.

冷却運転時には、圧縮機１で圧縮された高温高圧のガス冷媒は、四方弁５を通過し、熱源側熱交換器２により冷却されて凝縮液化される。この高圧液冷媒は、膨張装置３により減圧された後、利用側熱交換器４で被冷却媒体（冷却水や室内空気など）を冷却して蒸発し、低温低圧のガス冷媒となって圧縮機１に戻るサイクルを構成する。前記過冷却熱交換器１０は、主冷媒配管の冷媒が通過する１次側流路と、主冷媒回路から分岐されインジェクション回路２１を流れる冷媒が通過する２次側流路を有するもので、例えばプレート式熱交換器などで構成され、各々の冷媒が互いに熱交換される。 During the cooling operation, the high-temperature and high-pressure gas refrigerant compressed by the compressor 1 passes through the four-way valve 5, is cooled by the heat source side heat exchanger 2, and is condensed and liquefied. This high-pressure liquid refrigerant is decompressed by the expansion device 3, and then the medium to be cooled (cooling water, indoor air, etc.) is cooled and evaporated by the use side heat exchanger 4, and becomes a low-temperature and low-pressure gas refrigerant. Configure a cycle back to one. The supercooling heat exchanger 10 has a primary flow path through which a refrigerant in a main refrigerant pipe passes and a secondary flow path through which a refrigerant branched from the main refrigerant circuit and flows through the injection circuit 21 passes. It consists of a plate heat exchanger or the like, and each refrigerant exchanges heat with each other.

前記インジェクション回路２１の入口側に設けられた冷却用電磁弁１１を開とすることで、過冷却熱交換器１０を通過後の主冷媒配管の液冷媒の一部は、このインジェクション回路２１に流入し、冷却用逆止弁１２、電子膨張弁１５及びキャピラリチューブ１６を通過後、前記過冷却熱交換器１０の２次側流路を流れて、主流である１次側流路を流れる冷媒と熱交換した後、圧縮機の中間圧力部にインジェクションされ、圧縮される。 By opening the cooling solenoid valve 11 provided on the inlet side of the injection circuit 21, a part of the liquid refrigerant in the main refrigerant pipe after passing through the supercooling heat exchanger 10 flows into the injection circuit 21. And the refrigerant flowing through the secondary flow path of the supercooling heat exchanger 10 after passing through the cooling check valve 12, the electronic expansion valve 15 and the capillary tube 16, and flowing through the primary flow path which is the mainstream After heat exchange, it is injected into the intermediate pressure part of the compressor and compressed.

なお、冷却運転時に２次側流路を流れる冷媒を電子膨張弁１５で流量調整して減圧する場合、前記キャピラリチューブ１６はなくても構わないが、キャピラリチューブ１６を設けることで、電子膨張弁１５の感度を緩和させることができる。また、加熱運転時には、前記冷却用電磁弁１１を閉とし、前記バイパス回路２２の加熱用電磁弁１３を開とするが、この加熱運転時には前記電磁弁１１の１次側が低圧冷媒となるため、逆流防止のために前記逆止弁１２は設けられている。従って、前記電磁弁（開閉弁）１１の部分を二方弁等で構成することでこの開閉弁からの逆流の恐れがない場合には、前記逆止弁１２を除いても良い。 Note that when the refrigerant flowing through the secondary flow path during the cooling operation is decompressed by adjusting the flow rate with the electronic expansion valve 15, the capillary tube 16 may be omitted, but by providing the capillary tube 16, the electronic expansion valve The sensitivity of 15 can be relaxed. Further, during the heating operation, the cooling electromagnetic valve 11 is closed and the heating electromagnetic valve 13 of the bypass circuit 22 is opened, but during this heating operation, the primary side of the electromagnetic valve 11 becomes a low-pressure refrigerant, The check valve 12 is provided to prevent backflow. Therefore, the check valve 12 may be omitted when the solenoid valve (open / close valve) 11 is composed of a two-way valve or the like and there is no fear of backflow from the open / close valve.

次に、冷媒流量の調整に関し、図２の冷却運転時のモリエル線図を用いて説明する。電子膨張弁１５の冷媒流量調整は圧縮機１の吐出ガス温度を検知して行われる。吐出ガス温度が規定値（例えば９５℃）以下であれば、過冷却熱交換器１０の２次側流路出口を流れる冷媒がガス状態となるように流量を調整する。この２次側流路を流れる冷媒によって主流である１次側流路を流れる冷媒は、過冷却熱交換器１０で熱交換されて過冷却され、エンタルピ差Δｉ′が拡大するので、冷却能力は増加する。 Next, the adjustment of the refrigerant flow rate will be described using the Mollier diagram at the time of the cooling operation in FIG. The refrigerant flow rate adjustment of the electronic expansion valve 15 is performed by detecting the discharge gas temperature of the compressor 1. If the discharge gas temperature is a specified value (for example, 95 ° C.) or less, the flow rate is adjusted so that the refrigerant flowing through the secondary side channel outlet of the supercooling heat exchanger 10 is in a gas state. The refrigerant flowing through the primary flow path, which is the mainstream by the refrigerant flowing through the secondary flow path, is heat-exchanged by the supercooling heat exchanger 10 and supercooled, and the enthalpy difference Δi ′ increases, so the cooling capacity is To increase.

圧縮機１の中間圧力部はガス冷媒の状態でインジェクションされるので、通常の冷凍サイクルと同様の点線のような圧縮過程となる。従って、吐出ガス温度は通常サイクルと同等で冷却能力が増加するサイクルとなる。本サイクルは、一般にエコノマイザサイクルと呼ばれ、冷却能力増加に対し、消費電力の増加割合が小さいため、ＣＯＰ向上につながる効果がある。 Since the intermediate pressure part of the compressor 1 is injected in the state of a gas refrigerant, it becomes a compression process like a dotted line similar to a normal refrigeration cycle. Accordingly, the discharge gas temperature is the same as the normal cycle, and the cooling capacity increases. This cycle is generally called an economizer cycle, and has an effect of improving COP because the rate of increase in power consumption is small with respect to an increase in cooling capacity.

前記吐出ガス温度が規定値（例えば９５℃）以上の場合、過冷却熱交換器１０の２次側流路出口を流れる冷媒を湿り気味の状態とし、圧縮機の中間圧力部へ液冷媒を戻すことにより、吐出ガス温度を抑制して吐出ガス温度を適正値に保つように前記電子膨張弁１５を制御する。また、主流である１次側流路を流れる冷媒も、過冷却熱交換器１０で熱交換されて過冷却されるので、エンタルピ差Δｉ′も拡大されるから、冷却能力を増加させつつ、吐出ガス温度の制御が可能となる。更に、本実施例によれば、エコノマイザサイクルによる効果と、液インジェクションによる効果を連続的に制御することが可能であり、容量制御の安定化も図ることができる。 When the discharge gas temperature is equal to or higher than a specified value (for example, 95 ° C.), the refrigerant flowing through the secondary side channel outlet of the supercooling heat exchanger 10 is in a damp state, and the liquid refrigerant is returned to the intermediate pressure portion of the compressor. Thus, the electronic expansion valve 15 is controlled so as to keep the discharge gas temperature at an appropriate value by suppressing the discharge gas temperature. In addition, since the refrigerant flowing through the primary flow path, which is the mainstream, is also heat-cooled by the supercooling heat exchanger 10 and is supercooled, the enthalpy difference Δi ′ is also enlarged, so that the discharge capacity is increased while increasing the cooling capacity. The gas temperature can be controlled. Furthermore, according to the present embodiment, the effect by the economizer cycle and the effect by the liquid injection can be continuously controlled, and the capacity control can be stabilized.

なお、圧縮機の中間圧力部に液冷媒を膨張させて液インジェクションする従来の吐出ガス温度制御は、単なる液インジェクションサイクルであるため、冷却能力増加の効果は得られず、ＣＯＰ向上を図ることもできない。 In addition, the conventional discharge gas temperature control in which liquid refrigerant is expanded at the intermediate pressure portion of the compressor and liquid injection is a simple liquid injection cycle, so that the effect of increasing the cooling capacity cannot be obtained and the COP can be improved. Can not.

次に加熱運転時について説明する。加熱運転時には四方弁５を切り替えて、圧縮機１からの吐出ガスを最初に利用側熱交換器４に送るサイクルとなり、利用側熱交換器４が凝縮器、熱源側熱交換器２が蒸発器となる。圧縮機１で圧縮された高温高圧のガス冷媒は、利用側熱交換器４で冷却され凝縮液化される。この高圧液冷媒は、膨張装置３により減圧された後、熱源側熱交換器２で蒸発され、低温低圧のガス冷媒となって圧縮機１に戻るサイクルとなる。過冷却熱交換器１０の主流である１次側流路を流れる冷媒は、冷却運転時とは異なり低圧二相冷媒となっている。 Next, the heating operation will be described. During the heating operation, the four-way valve 5 is switched and the discharge gas from the compressor 1 is first sent to the use side heat exchanger 4. The use side heat exchanger 4 is a condenser and the heat source side heat exchanger 2 is an evaporator. It becomes. The high-temperature and high-pressure gas refrigerant compressed by the compressor 1 is cooled by the use-side heat exchanger 4 and liquefied. This high-pressure liquid refrigerant is depressurized by the expansion device 3 and then evaporated in the heat source side heat exchanger 2 to become a low-temperature and low-pressure gas refrigerant and return to the compressor 1. Unlike the cooling operation, the refrigerant flowing through the primary flow path that is the main flow of the supercooling heat exchanger 10 is a low-pressure two-phase refrigerant.

加熱運転時にはインジェクション回路２１の冷却用電磁弁１１は閉とされる。バイパス回路２２の加熱用電磁弁１３を開とすることで、利用側熱交換器４により冷却凝縮された液冷媒は、加熱用逆止弁１４を通過し、その後インジェクション回路２１に設けられた電子膨張弁１５により冷媒流量が調整され、キャピラリチューブ１６で減圧されて過冷却熱交換器１０の２次側流路を通過した後、圧縮機の中間圧力部に流入し圧縮される。加熱運転時の過冷却熱交換器の１次側流路も膨張装置３で減圧された低圧低温冷媒が流れているため、過冷却熱交換器の２次側流路を流れる冷媒温度と同等であり、このため過冷却熱交換器１０における熱交換量は、上述した冷却運転時に比べ非常に小さくなる。 During the heating operation, the cooling solenoid valve 11 of the injection circuit 21 is closed. By opening the heating electromagnetic valve 13 of the bypass circuit 22, the liquid refrigerant cooled and condensed by the use side heat exchanger 4 passes through the heating check valve 14, and then the electrons provided in the injection circuit 21. The refrigerant flow rate is adjusted by the expansion valve 15, the pressure is reduced by the capillary tube 16, passes through the secondary flow path of the supercooling heat exchanger 10, and then flows into the intermediate pressure portion of the compressor to be compressed. Since the low-pressure low-temperature refrigerant depressurized by the expansion device 3 is also flowing in the primary flow path of the supercooling heat exchanger during the heating operation, it is equivalent to the refrigerant temperature flowing through the secondary flow path of the supercooling heat exchanger. For this reason, the amount of heat exchange in the supercooling heat exchanger 10 is much smaller than that in the cooling operation described above.

前記電子膨張弁１５による冷媒流量の調整に関して、図３の加熱運転時のモリエル線図を用いて説明する。
電子膨張弁１５による冷媒流量の調整は、冷却運転時と同様に、圧縮機の吐出ガス温度を検知して行う。前記吐出ガス温度が規定値（例えば９５℃）以上になると、吐出ガス温度が規定値になるよう前記電子膨張弁１５の開度を調整し、圧縮機へのインジェクション量を調整する。圧縮機１の中間圧力部に液インジェクションすることにより、図３のように、中間圧力部での温度が低下し、結果として吐出ガス温度を低下させることができる。 The adjustment of the refrigerant flow rate by the electronic expansion valve 15 will be described using the Mollier diagram at the time of heating operation in FIG.
Adjustment of the refrigerant flow rate by the electronic expansion valve 15 is performed by detecting the discharge gas temperature of the compressor as in the cooling operation. When the discharge gas temperature becomes a specified value (for example, 95 ° C.) or more, the opening degree of the electronic expansion valve 15 is adjusted so that the discharge gas temperature becomes a specified value, and the injection amount to the compressor is adjusted. By liquid injection into the intermediate pressure part of the compressor 1, the temperature at the intermediate pressure part is lowered as shown in FIG. 3, and as a result, the discharge gas temperature can be lowered.

一方、加熱運転時に、冷却運転時同様の通常のエコノマイザサイクルを構成して主冷媒配管を流れる冷媒を過冷却させ、吐出ガス温度抑制も図るサイクルとした場合を仮定すると、図３の細い点線で示すように、エンタルピ差Δｉ′は大きくなるものの、利用側熱交換器での熱交換量は変わらないから加熱能力の増加には寄与せず、熱源側熱交換器での必要能力が逆に多く必要となってしまう。このため、Δｉ′を大とすることは吸入圧力の低下となり、加熱能力が低下するだけでなく、ＣＯＰも低下させてしまう。 On the other hand, assuming a cycle in which a normal economizer cycle similar to that in the cooling operation is configured during the heating operation and the refrigerant flowing through the main refrigerant pipe is supercooled to suppress the discharge gas temperature, the thin dotted line in FIG. As shown, although the enthalpy difference Δi ′ increases, the amount of heat exchange in the use side heat exchanger does not change, so it does not contribute to an increase in heating capacity, and the required capacity in the heat source side heat exchanger is conversely large. It becomes necessary. For this reason, increasing Δi ′ decreases the suction pressure, which not only lowers the heating capacity but also reduces the COP.

これに対して、本実施例では、加熱運転時には過冷却を大きくとらない構成となるので、冷凍装置のＣＯＰ向上を図りつつ圧縮機の吐出温度制御が可能になる。
以上説明したように、本実施例によれば、冷却運転時及び加熱運転時共に、圧縮機の吐出ガス温度を制御できると共に、ＣＯＰを向上させることも可能になる。 On the other hand, in this embodiment, since the supercooling is not increased during the heating operation, it is possible to control the discharge temperature of the compressor while improving the COP of the refrigeration apparatus.
As described above, according to the present embodiment, the discharge gas temperature of the compressor can be controlled and the COP can be improved during both the cooling operation and the heating operation.

本発明の実施例２を図４により説明する。この実施例は、図１に示す実施例１における電子膨張弁１５及びキャピラリチューブ１６の部分の構成を変えたもので、他の部分の構成については実施例１と同様であり、同一符号を付してその説明を省略する。 A second embodiment of the present invention will be described with reference to FIG. In this embodiment, the configuration of the electronic expansion valve 15 and the capillary tube 16 in the first embodiment shown in FIG. 1 is changed, and the configuration of the other portions is the same as that of the first embodiment, and the same reference numerals are given. Therefore, the description is omitted.

本実施例においては、過冷却熱交換器１０の２次側流路を流れる冷媒の流量を調整するため、図１に示す電子膨張弁１５、キャピラリチューブ１６に代えて、電磁弁１７とキャピラリチューブ１８を設け、更にこの電磁弁１７とキャピラリチューブ１８と並列に電磁弁１９とキャピラリチューブ２０を設けるようにしたものである。前記キャピラリチューブ１８と２０とは異なる流路抵抗となるように、異なるサイズのものを使用している。 In the present embodiment, in order to adjust the flow rate of the refrigerant flowing through the secondary side flow path of the supercooling heat exchanger 10, an electromagnetic valve 17 and a capillary tube are used instead of the electronic expansion valve 15 and the capillary tube 16 shown in FIG. 18 and further, an electromagnetic valve 19 and a capillary tube 20 are provided in parallel with the electromagnetic valve 17 and the capillary tube 18. The capillary tubes 18 and 20 have different sizes so as to have different flow path resistances.

このように構成することにより、前記電磁弁１７，１９の開閉を制御することで過冷却熱交換器１０の２次側流路を流れる冷媒の流量を４段階に調整することが可能となる。
本実施例によれば、図１に示す電子膨張弁１５を使用することなく、インジェクション回路２１を流れる冷媒流量を制御することができるから、圧縮機吐出ガス温度を一定に保つように冷媒流量を調整でき且つ安価な冷凍装置が実現可能となる。また、実施例１と同様に、冷却運転時及び加熱運転時共に、圧縮機吐出ガス温度を制御できると共に、ＣＯＰの向上も図れる冷凍装置を得ることができる。 With this configuration, it is possible to adjust the flow rate of the refrigerant flowing in the secondary flow path of the supercooling heat exchanger 10 in four stages by controlling the opening and closing of the electromagnetic valves 17 and 19.
According to this embodiment, the flow rate of the refrigerant flowing through the injection circuit 21 can be controlled without using the electronic expansion valve 15 shown in FIG. 1, so the flow rate of the refrigerant is set so as to keep the compressor discharge gas temperature constant. An refrigeration apparatus that can be adjusted and is inexpensive can be realized. Further, similarly to the first embodiment, it is possible to obtain a refrigeration apparatus capable of controlling the compressor discharge gas temperature and improving COP both during the cooling operation and the heating operation.

なお、本実施例では、電磁弁とキャピラリチューブの組を２組、並列に配置する構成としたが、３組以上を並列に配置する構成としても良い。更に、流量調整が開と閉の２段階でも良い場合には、前記電磁弁とキャピラリチューブの組は１組とすることも可能である。 In this embodiment, two sets of solenoid valves and capillary tubes are arranged in parallel, but three or more sets may be arranged in parallel. Furthermore, when the flow rate adjustment may be performed in two stages of opening and closing, the set of the solenoid valve and the capillary tube may be one set.

本発明の実施例３を図５により説明する。この実施例は、図１に示す実施例１における圧縮機１を、圧縮機１ａ，１ｂの２台としたマルチ圧縮機サイクルとした点が異なる。また、圧縮機を２台としたことにより、過冷却熱交換器も１０ａ，１０ｂの２個を並列に配置し、過冷却熱交換器の２次側回路（インジェクション回路２１A，２１Ｂ）も各圧縮機毎に設けたものである。他の部分の構成については実施例１と同様であり、同一符号を付してその説明を省略する。 A third embodiment of the present invention will be described with reference to FIG. This embodiment is different in that the compressor 1 in Embodiment 1 shown in FIG. 1 is a multi-compressor cycle in which two compressors 1a and 1b are used. In addition, by using two compressors, two supercooling heat exchangers 10a and 10b are arranged in parallel, and the secondary circuit of the supercooling heat exchanger (injection circuits 21A and 21B) is also compressed. It is provided for each machine. The configuration of other parts is the same as that of the first embodiment, and the same reference numerals are given and the description thereof is omitted.

本実施例においては、過冷却熱交換器１０ａと１０ｂが並列に設けられ、主冷媒配管を分岐させてそれぞれの過冷却熱交換器の主流側となる１次側流路に接続されている。インジェクション回路２１も、冷却用逆止弁１２及び加熱用逆止弁１４の下流側からインジェクション回路２１Ａと２１Ｂに分岐され、インジェクション回路２１Ａは過冷却熱交換器１０ａの２次側流路に接続され、インジェクション回路２１Ｂは過冷却熱交換器１０ｂの２次側流路に接続されている。 In the present embodiment, the supercooling heat exchangers 10a and 10b are provided in parallel, and the main refrigerant pipe is branched and connected to the primary flow path that is the mainstream side of each supercooling heat exchanger. The injection circuit 21 is also branched into the injection circuits 21A and 21B from the downstream side of the cooling check valve 12 and the heating check valve 14, and the injection circuit 21A is connected to the secondary side flow path of the supercooling heat exchanger 10a. The injection circuit 21B is connected to the secondary flow path of the supercooling heat exchanger 10b.

また、各インジェクション回路２１Ａ，２１Ｂの過冷却熱交換器１０ａまたは１０ｂ上流側には、それぞれ電子膨張弁１５ａまたは１５ｂとキャピラリチューブ１６ａまたは１６ｂが設けられている。前記インジェクション回路２１Ａは圧縮機１ａの中間圧力部に接続され、前記インジェクション回路２１Ｂは圧縮機１ｂの中間圧力部に接続されている。 In addition, an electronic expansion valve 15a or 15b and a capillary tube 16a or 16b are provided on the upstream side of the supercooling heat exchanger 10a or 10b of the injection circuits 21A and 21B, respectively. The injection circuit 21A is connected to the intermediate pressure part of the compressor 1a, and the injection circuit 21B is connected to the intermediate pressure part of the compressor 1b.

なお、８ａ1，８ｂ1は各圧縮機１ａ，１ｂとアキュームレータ７とを接続する冷媒配管にそれぞれ設けられたストレーナである。
このように構成することにより、前記電子膨張弁１５ａ，１５ｂを制御することで、各過冷却熱交換器１０ａ，１０ｂの２次側流路を流れる冷媒の流量を実施例１と同様に調整することが可能となり、また各圧縮機１ａ，１ｂへインジェクションされる冷媒流量も制御することができる。 Reference numerals 8a1 and 8b1 denote strainers provided in refrigerant pipes connecting the compressors 1a and 1b and the accumulator 7, respectively.
With this configuration, by controlling the electronic expansion valves 15a and 15b, the flow rate of the refrigerant flowing through the secondary flow paths of the subcooling heat exchangers 10a and 10b is adjusted in the same manner as in the first embodiment. It is also possible to control the flow rate of the refrigerant injected into the compressors 1a and 1b.

本実施例によれば、圧縮機を複数台とした冷凍装置においても、各インジェクション回路２１Ａ，２１Ｂを流れる冷媒流量を制御することができるから、各圧縮機の吐出ガス温度を一定に保つように調整することが可能となる。また、実施例１と同様に、冷却運転時及び加熱運転時共に、各圧縮機の吐出ガス温度を制御できると共に、ＣＯＰの向上も図れる冷凍装置を得ることができる。 According to this embodiment, even in a refrigeration system having a plurality of compressors, the flow rate of refrigerant flowing through each injection circuit 21A, 21B can be controlled, so that the discharge gas temperature of each compressor is kept constant. It becomes possible to adjust. Further, similarly to the first embodiment, it is possible to obtain a refrigeration apparatus capable of controlling the discharge gas temperature of each compressor and improving COP during both the cooling operation and the heating operation.

なお、前記過冷却熱交換器を１個とし、過冷却熱交換器の下流側のインジェクション回路を分岐させて各圧縮機の中間圧力部に接続する方法もある。この場合、一方の圧縮機が停止すると、停止した圧縮機の中間圧力部にも冷媒が流れてしまい、冷凍サイクルが成り立たなくなってしまうので、逆止弁及び電磁弁を分岐された前記インジェクション回路のそれぞれに設け、圧縮機のＯＮ−ＯＦＦに応じて各インジェクション回路を遮断する必要がある。しかし、この方法では、圧縮機の中間圧力部の脈動が大きいことから、弁類の破損や故障といった問題が生じる可能性がある。これに対し、図５に示す実施例では、過冷却器と圧縮機の中間圧力部との間に弁類を配置する必要がなく、インジェクション回路と過冷却器の容積により脈動を緩和させることができるから、弁類の破損や故障を防止でき、信頼性確保の上から有効である。 There is also a method in which one supercooling heat exchanger is provided, and an injection circuit on the downstream side of the supercooling heat exchanger is branched and connected to an intermediate pressure portion of each compressor. In this case, when one of the compressors stops, the refrigerant also flows through the intermediate pressure portion of the stopped compressor, and the refrigeration cycle is not established. Therefore, the check valve and the solenoid valve are branched from the injection circuit. It is necessary to shut off each injection circuit in accordance with ON / OFF of the compressor provided for each. However, in this method, since the pulsation of the intermediate pressure portion of the compressor is large, there is a possibility that problems such as breakage or failure of valves occur. On the other hand, in the embodiment shown in FIG. 5, it is not necessary to arrange valves between the subcooler and the intermediate pressure part of the compressor, and the pulsation can be reduced by the volume of the injection circuit and the subcooler. Therefore, damage and failure of valves can be prevented, which is effective for ensuring reliability.

以上述べた本発明の各実施例によれば、以下の効果を得ることができる。
冷却運転時には、過冷却熱交換器により過冷却を大きくするエコノマイザ回路を備えているので、冷却能力を向上できると共に効率向上（ＣＯＰ向上）も図ることが可能となる。また、吐出ガス温度が上昇した場合はインジェクション回路の流量を増加させることで湿り気味の冷媒を圧縮機中間圧力部に戻すことができ、これにより液インジェクション作用をさせることで、吐出ガス温度を調整することが可能となり、信頼性向上も図ることができる。更に、本実施例によれば、エコノマイザとしての作用と液インジェクションとしての作用を１系統で連続的に行わせることが可能となり、エコノマイザ回路と液インジェクション回路を別々に設ける必要がないから原価低減も図ることができる効果がある。 According to each embodiment of the present invention described above, the following effects can be obtained.
During the cooling operation, the economizer circuit that increases the supercooling by the supercooling heat exchanger is provided, so that the cooling capacity can be improved and the efficiency (COP improvement) can be improved. In addition, when the discharge gas temperature rises, it is possible to return the humid refrigerant to the compressor intermediate pressure section by increasing the flow rate of the injection circuit, thereby adjusting the discharge gas temperature by causing liquid injection action It is possible to improve reliability. Furthermore, according to the present embodiment, it is possible to continuously perform the operation as an economizer and the operation as a liquid injection in one system, and it is not necessary to separately provide an economizer circuit and a liquid injection circuit, thereby reducing cost. There is an effect that can be achieved.

加熱運転時には、過冷却器で過冷却を取らずに湿り冷媒を圧縮機の中間圧力部に液インジェクションすることが可能となるので、加熱能力及びＣＯＰを低下させることなく圧縮機の信頼性向上を図ることができる。 During heating operation, it becomes possible to liquid-inject the wet refrigerant into the intermediate pressure part of the compressor without taking overcooling with the supercooler, so that the reliability of the compressor can be improved without lowering the heating capacity and COP. Can be planned.

１，１ａ，１ｂ圧縮機
２熱源側熱交換器
３膨張装置
４利用側熱交換器
５四方弁
６冷媒量調節器
７アキュームレータ
８ａ，８ｂ，８ｃ，８ａ1，８ｂ1 ストレーナ
９，９ａ，９ｂ主回路逆止弁
１０，１０ａ，１０ｂ過冷却熱交換器
１１冷却用電磁弁（開閉弁）
１２冷却用逆止弁
１３加熱用電磁弁（開閉弁）
１４加熱用逆止弁
１５，１５ａ，１５ｂ電子膨張弁（流量調整手段または減圧手段）
１６，１６ａ，１６ｂキャピラリチューブ（減圧手段）
１７，１９電磁弁
１８，２０キャピラリチューブ
２１，２１Ａ，２１Ｂインジェクション回路（２１ａ…分岐部）
２２バイパス回路（２２ａ…分岐部）。 1, 1a, 1b Compressor 2 Heat source side heat exchanger 3 Expansion device 4 Use side heat exchanger 5 Four-way valve 6 Refrigerant amount regulator 7 Accumulator 8a, 8b, 8c, 8a1, 8b1 Strainer 9, 9a, 9b Reverse main circuit Stop valve 10, 10a, 10b Supercooling heat exchanger 11 Cooling solenoid valve (open / close valve)
12 Check valve for cooling 13 Solenoid valve for heating (open / close valve)
14 Heating check valve 15, 15a, 15b Electronic expansion valve (flow rate adjusting means or pressure reducing means)
16, 16a, 16b Capillary tube (pressure reduction means)
17, 19 Solenoid valve 18, 20 Capillary tube 21, 21A, 21B Injection circuit (21a ... branching portion)
22 Bypass circuit (22a ... branching part).

Claims

圧縮機、四方弁、熱源側熱交換器、膨張装置及び利用側熱交換器が冷媒配管で接続された冷凍装置において、
前記熱源側熱交換器と前記膨張装置の間に設けられた過冷却熱交換器と、
前記熱源側熱交換器と前記膨張装置との間の前記冷媒配管から分岐され前記過冷却熱交換器を通過後、前記圧縮機の中間圧力部に接続されるインジェクション回路と、
このインジェクション回路の前記過冷却熱交換器上流側に、上流側から順に設けられた開閉弁及び減圧手段と、
前記膨張装置と前記利用側熱交換器との間の前記冷媒配管から分岐され、前記インジェクション回路の前記開閉弁と減圧手段との間に接続されるバイパス回路と、
このバイパス回路に設けられた開閉弁と
を備えることを特徴とする冷凍装置。 In a refrigeration system in which a compressor, a four-way valve, a heat source side heat exchanger, an expansion device, and a use side heat exchanger are connected by a refrigerant pipe,
A supercooling heat exchanger provided between the heat source side heat exchanger and the expansion device;
An injection circuit that is branched from the refrigerant pipe between the heat source side heat exchanger and the expansion device, passes through the supercooling heat exchanger, and is connected to an intermediate pressure portion of the compressor;
On-off valve and pressure reducing means provided in order from the upstream side on the upstream side of the supercooling heat exchanger of this injection circuit,
A bypass circuit branched from the refrigerant pipe between the expansion device and the use side heat exchanger, and connected between the on-off valve of the injection circuit and a pressure reducing means;
A refrigerating apparatus comprising an on-off valve provided in the bypass circuit.

圧縮機、四方弁、熱源側熱交換器、膨張装置及び利用側熱交換器が冷媒配管で接続された冷凍装置において、
前記熱源側熱交換器と前記膨張装置の間に設けられた過冷却熱交換器と、
前記熱源側熱交換器と前記膨張装置との間の前記冷媒配管から分岐され前記過冷却熱交換器を通過後、前記圧縮機の中間圧力部に接続されるインジェクション回路と、
このインジェクション回路の前記過冷却熱交換器上流側に、上流側から順に設けられた開閉弁、電磁弁及びキャピラリチューブと、
前記膨張装置と前記利用側熱交換器との間の前記冷媒配管から分岐され、前記インジェクション回路の前記開閉弁と前記電磁弁との間に接続されるバイパス回路と、
このバイパス回路に設けられた開閉弁と
を備えることを特徴とする冷凍装置。 In a refrigeration system in which a compressor, a four-way valve, a heat source side heat exchanger, an expansion device, and a use side heat exchanger are connected by a refrigerant pipe,
A supercooling heat exchanger provided between the heat source side heat exchanger and the expansion device;
An injection circuit that is branched from the refrigerant pipe between the heat source side heat exchanger and the expansion device, passes through the supercooling heat exchanger, and is connected to an intermediate pressure portion of the compressor;
On the upstream side of the supercooling heat exchanger of this injection circuit, an on-off valve, a solenoid valve and a capillary tube provided in order from the upstream side,
A bypass circuit branched from the refrigerant pipe between the expansion device and the use side heat exchanger, and connected between the on-off valve and the solenoid valve of the injection circuit;
A refrigerating apparatus comprising an on-off valve provided in the bypass circuit.

請求項２において、前記インジェクション回路に設けられた前記電磁弁とキャピラリチューブの組を並列に複数組配置したことを特徴とする冷凍装置。 3. The refrigeration apparatus according to claim 2, wherein a plurality of sets of the solenoid valve and capillary tube provided in the injection circuit are arranged in parallel.

請求項３において、並列に複数組配置された前記キャピラリチューブはそれぞれ異なる流路抵抗となるように、異なるサイズのものとしたことを特徴とする冷凍装置。 4. The refrigeration apparatus according to claim 3, wherein a plurality of sets of capillary tubes arranged in parallel have different sizes so as to have different flow path resistances.

複数台の圧縮機、四方弁、熱源側熱交換器、膨張装置及び利用側熱交換器が冷媒配管で接続された冷凍装置において、
前記熱源側熱交換器と前記膨張装置の間に設けられた過冷却熱交換器と、
前記熱源側熱交換器と前記膨張装置との間の前記冷媒配管から分岐され前記過冷却熱交換器を通過後、前記各圧縮機の中間圧力部に接続されるインジェクション回路と、
このインジェクション回路の前記過冷却熱交換器上流側に、上流側から順に設けられた開閉弁及び減圧手段と、
前記膨張装置と前記利用側熱交換器との間の前記冷媒配管から分岐され、前記インジェクション回路の前記開閉弁と減圧手段との間に接続されるバイパス回路と、
このバイパス回路に設けられた開閉弁と
を備えることを特徴とする冷凍装置。 In a refrigeration system in which a plurality of compressors, four-way valves, a heat source side heat exchanger, an expansion device, and a use side heat exchanger are connected by a refrigerant pipe,
A supercooling heat exchanger provided between the heat source side heat exchanger and the expansion device;
An injection circuit that is branched from the refrigerant pipe between the heat source side heat exchanger and the expansion device, passes through the supercooling heat exchanger, and is connected to an intermediate pressure portion of each compressor;
On-off valve and pressure reducing means provided in order from the upstream side on the upstream side of the supercooling heat exchanger of this injection circuit,
A bypass circuit branched from the refrigerant pipe between the expansion device and the use side heat exchanger, and connected between the on-off valve of the injection circuit and a pressure reducing means;
A refrigerating apparatus comprising an on-off valve provided in the bypass circuit.

請求項５において、前記過冷却熱交換器は並列に複数台設けられ、主流となる前記冷媒配管を分岐させてそれぞれの過冷却熱交換器の主流側となる１次側流路に接続させ、前記インジェクション回路も前記開閉弁の下流側から複数に分岐され、これら複数に分岐されたそれぞれのインジェクション回路は複数台設けられた前記過冷却熱交換器の２次側流路に接続され、分岐された前記各インジェクション回路の過冷却熱交換器上流側に前記減圧手段が設けられ、この減圧手段は電子膨張弁、または電子膨張弁とキャピラリチューブで構成されていることを特徴とする冷凍装置。 In claim 5, a plurality of the supercooling heat exchangers are provided in parallel, branching the refrigerant pipe that is the mainstream, and connected to the primary flow path that is the mainstream side of each supercooling heat exchanger, The injection circuit is also branched into a plurality from the downstream side of the on-off valve, and each of the plurality of branched injection circuits is connected to a secondary flow path of the supercooling heat exchanger provided in a plurality and branched. The refrigeration apparatus is characterized in that the decompression means is provided upstream of the supercooling heat exchanger of each injection circuit, and the decompression means is composed of an electronic expansion valve or an electronic expansion valve and a capillary tube.

請求項１〜５の何れかにおいて、前記過冷却熱交換器は１次側流路と２次側流路を備え、前記１次側流路は主流となる前記冷媒配管に接続され、前記２次側流路は前記インジェクション回路に接続され、１次側流路を流れる冷媒と２次側流路を流れる冷媒が互いに熱交換される構成とされていることを特徴とする冷凍装置。 In any one of Claims 1-5, the said supercooling heat exchanger is provided with the primary side flow path and the secondary side flow path, and the said primary side flow path is connected to the said refrigerant | coolant piping used as the mainstream, The said 2 The refrigerating apparatus is characterized in that the secondary flow path is connected to the injection circuit, and the refrigerant flowing through the primary flow path and the refrigerant flowing through the secondary flow path are configured to exchange heat with each other.

請求項１または５において、前記インジェクション回路及びバイパス回路に設けられた開閉弁は電磁弁であり、前記バイパス回路の前記電磁弁の下流側には逆止弁が設けられ、更に前記インジェクション回路の前記電磁弁と前記減圧手段との間にも逆止弁が設けられ、前記バイパス回路は前記インジェクション回路の前記逆止弁と減圧手段との間に接続されていることを特徴とする冷凍装置。 In Claim 1 or 5, the on-off valve provided in the injection circuit and the bypass circuit is an electromagnetic valve, a check valve is provided downstream of the electromagnetic valve of the bypass circuit, and the injection circuit further includes the check valve. A refrigerating apparatus in which a check valve is also provided between the electromagnetic valve and the pressure reducing means, and the bypass circuit is connected between the check valve and the pressure reducing means of the injection circuit.

請求項１、５または８の何れかにおいて、前記インジェクション回路に設けられた前記減圧手段は、電子膨張弁、キャピラリチューブ、又は電子膨張弁とキャピラリチューブの何れかにより構成されていることを特徴とする冷凍装置。 9. The pressure-reducing means provided in the injection circuit according to claim 1, wherein the pressure-reducing means includes an electronic expansion valve, a capillary tube, or an electronic expansion valve and a capillary tube. Refrigeration equipment.

請求項１〜９の何れかにおいて、前記インジェクション回路は、前記過冷却熱交換器と前記膨張装置との間の前記冷媒配管から分岐され前記過冷却熱交換器を通過後、前記圧縮機の中間圧力部に接続される構成としたことを特徴とする冷凍装置。 10. The injection circuit according to claim 1, wherein the injection circuit is branched from the refrigerant pipe between the supercooling heat exchanger and the expansion device, passes through the supercooling heat exchanger, and then intermediates the compressor. A refrigeration apparatus characterized by being configured to be connected to a pressure section.