JP2010139097A

JP2010139097A - Air conditioner

Info

Publication number: JP2010139097A
Application number: JP2008313223A
Authority: JP
Inventors: Satoru Yanaike; 悟梁池; Makoto Saito; 信齊藤; Osamu Morimoto; 修森本
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2008-12-09
Filing date: 2008-12-09
Publication date: 2010-06-24

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air conditioner capable of suppressing lowering of a room temperature and the like and keeping and continuing comfort by continuing a heating operation without degrading heating efficiency even in a defrosting operation. <P>SOLUTION: In this air conditioner 100, an outdoor heat exchanger 7a (outdoor heat exchanger 7b) is constituted by alternately vertically arranging a divided heat exchanger 8a (divided heat exchanger 8b) and a divided heat exchanger 9a (divided heat exchanger 9b) in which different paths are formed. A flow channel switching device 2b to be communicated with a discharge side or a suction side of a compressor 1 is disposed at one end of the path connected with the divided heat exchanger 7a, and a pressure reducing device 4b is connected with the other end. Further a flow channel switching device 2a is connected with one end of the path connected with the divided heat exchanger 9a, and a pressure reducing device 4b is connected with the other end through a solenoid valve 6a. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

本発明は、蒸気圧縮式の空気調和機に関するものであり、特に暖房効率を低下させることなく室外熱交換器への着霜状態を解消する除霜運転を実行可能にした空気調和機に関するものである。 The present invention relates to a vapor compression type air conditioner, and more particularly to an air conditioner capable of performing a defrosting operation for eliminating a frosting state on an outdoor heat exchanger without reducing heating efficiency. is there.

従来から、暖房運転時において蒸発器として機能する室外熱交換器に付着した霜を溶解させる除霜運転（デフロスト運転）を実行することができる空気調和機が存在する。また、室外熱交換器に着霜が起こる運転状況においても、暖房を中断することなく除霜運転を実行可能にした空気調和機も存在する。このような空気調和機では、複数の室外熱交換器を室内熱交換器に対して並列に接続し、それぞれの室外熱交換器の一端に圧縮機の吐出側か吸入側のいずれかに連通できるような冷媒流路の切替装置を配し、それぞれの室外熱交換器を凝縮器もしくは蒸発器に切り替えることで、一方を凝縮器としながらも他方を蒸発器として運転可能であり、室外熱交換器の交互除霜によって、暖房運転を中断することなく除霜運転を可能としている。 Conventionally, there is an air conditioner that can perform a defrosting operation (defrosting operation) for dissolving frost attached to an outdoor heat exchanger that functions as an evaporator during a heating operation. There is also an air conditioner that can perform a defrosting operation without interrupting heating even in an operation state in which frost formation occurs in the outdoor heat exchanger. In such an air conditioner, a plurality of outdoor heat exchangers are connected in parallel to the indoor heat exchanger, and one end of each outdoor heat exchanger can communicate with either the discharge side or the suction side of the compressor. By arranging such a refrigerant flow switching device and switching each outdoor heat exchanger to a condenser or an evaporator, it is possible to operate one as a condenser but the other as an evaporator. The alternate defrosting enables defrosting operation without interrupting heating operation.

そのようなものとして、「圧縮機、室外熱交換器、膨張機構を有する室外ユニットと、室内熱交換器を有する複数台の室内ユニットが接続され、前記室内ユニットは冷房運転と暖房運転とが混在して運転される空気調和機において、前記室外ユニットは複数台に分割された前記室外熱交換器と、各々の前記室外熱交換器を仕切るように取りつけられた仕切板と、各々の前記室外熱交換器の上方のモータに連結されたファンとを備え、除霜運転する場合、複数台の前記室外熱交換器うち一方を凝縮器として他方を蒸発器として作用させ、前記圧縮機からの吐出ガスを室内熱交換器へ導く空気調和機」が提案されている（たとえば、特許文献１参照）。 As such, “an outdoor unit having a compressor, an outdoor heat exchanger, an expansion mechanism, and a plurality of indoor units having an indoor heat exchanger are connected, and the indoor unit has both cooling operation and heating operation. In the air conditioner operated as described above, the outdoor unit is divided into a plurality of the outdoor heat exchangers, a partition plate mounted to partition each of the outdoor heat exchangers, and each of the outdoor heats. A fan connected to the motor above the exchanger, and when performing a defrosting operation, one of the plurality of outdoor heat exchangers acts as a condenser and the other acts as an evaporator, and discharge gas from the compressor An air conditioner that guides the air to the indoor heat exchanger ”has been proposed (see, for example, Patent Document 1).

特許第２９９７５０４号公報（第２、３頁、第１図）Japanese Patent No. 2997504 (pages 2, 3 and 1)

特許文献１に記載されているような空気調和機においては、除霜運転を行なう室外熱交換器の内容積が大きいと、蒸発器から凝縮器に切替わった際に冷媒が除霜運転を行う熱交換器に大量に溜まり込み、冷媒不足となってしまうという課題があった。除霜運転時の冷媒不足防止策として、除霜運転する熱交換器を細かく分割することで、冷媒が溜まり込む内容積を減らすことが考えられる。しかしながら、特許文献１に記載されているような空気調和機構成においては、熱交換器の分割数と同数の流路切替装置が必要となるため、その分、製造に要する手間及びコストの増加に繋がってしまうことになる。 In the air conditioner described in Patent Document 1, when the internal volume of the outdoor heat exchanger that performs the defrosting operation is large, the refrigerant performs the defrosting operation when the evaporator is switched to the condenser. There was a problem that a large amount of heat accumulated in the heat exchanger and the refrigerant became insufficient. As a measure for preventing refrigerant shortage during the defrosting operation, it is conceivable to reduce the internal volume in which the refrigerant accumulates by finely dividing the heat exchanger that performs the defrosting operation. However, in the air conditioner configuration as described in Patent Document 1, the same number of flow path switching devices as the number of divisions of the heat exchanger are required, which increases the labor and cost required for manufacturing. It will be connected.

本発明は、上記のような課題を解決するためになされたもので、除霜運転中も暖房効率を低下させることなく暖房運転を継続することで、室温低下等を抑制し、快適性を維持継続することを可能とした空気調和機を提供することを目的としている。 The present invention has been made to solve the above-described problems, and maintains the comfort by suppressing the temperature decrease and the like by continuing the heating operation without reducing the heating efficiency even during the defrosting operation. It aims to provide an air conditioner that can be continued.

本発明に係る空気調和機は、圧縮機と、第１流路切替装置と、室内熱交換器と、第１減圧装置と、前記室内熱交換器及び前記第１減圧装置に対して並列に設けられた少なくとも２台の室外熱交換器と、が接続された冷媒回路を有する空気調和機であって、前記各室外熱交換器は、異なるパスが通されている第１熱交換器及び第２熱交換器が上下方向に交互に配置されて構成されており、前記第１熱交換器を通るパスの一端に前記圧縮機の吐出側又は吸入側へ連通させるための第２流路切替装置を、他端に第２減圧装置を、接続し、前記第２熱交換器を通るパスの一端に前記第１流路切替装置を、他端に開閉弁を介して前記第２減圧装置を、接続していることを特徴とする。 An air conditioner according to the present invention is provided in parallel with a compressor, a first flow switching device, an indoor heat exchanger, a first pressure reducing device, the indoor heat exchanger, and the first pressure reducing device. An air conditioner having a refrigerant circuit connected to at least two outdoor heat exchangers, wherein each of the outdoor heat exchangers includes a first heat exchanger and a second heat exchanger through which different paths are passed. A second flow path switching device configured to communicate with the discharge side or the suction side of the compressor at one end of a path passing through the first heat exchanger. The other pressure reducing device is connected to the other end, the first flow path switching device is connected to one end of a path passing through the second heat exchanger, and the second pressure reducing device is connected to the other end via an opening / closing valve. It is characterized by that.

本発明に係る空気調和機によれば、２つのパスで構成されている室外熱交換器をすくなくとも２台備えているので、冷媒不足を防止でき、除霜運転中も暖房効率を低下させることなく暖房運転を継続することで、室温低下等を抑制し、快適性を維持継続することができる。また、流路切替装置（四方弁）の設置個数を増加させることがないので、製造に要する手間及びコストの低減を図ることができる。 According to the air conditioner according to the present invention, since at least two outdoor heat exchangers configured by two passes are provided, it is possible to prevent refrigerant shortage, and without reducing heating efficiency during the defrosting operation. By continuing the heating operation, it is possible to suppress a decrease in room temperature or the like and maintain comfort. Further, since the number of installed flow path switching devices (four-way valves) is not increased, labor and cost required for manufacturing can be reduced.

以下、本発明の実施の形態を図面に基づいて説明する。
図１は、本発明の実施の形態に係る空気調和機１００の冷媒回路構成の一例を示す概略構成図である。図２は、第１室外熱交換器７ａ及び第２室外熱交換器７ｂの分割パターンの一例を示す斜視図である。図３は、除霜運転時の除霜状態をイメージ化して示す概念図である。図１〜図３に基づいて、空気調和機１００の冷媒回路構成及び動作について説明する。この空気調和機１００は、冷媒を循環させる冷凍サイクル（ヒートポンプサイクル）を利用して、冷房運転あるいは暖房運転を実行するものである。なお、図１を含め、以下の図面では各構成部材の大きさの関係が実際のものとは異なる場合がある。 Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic configuration diagram illustrating an example of a refrigerant circuit configuration of an air conditioner 100 according to an embodiment of the present invention. FIG. 2 is a perspective view showing an example of a division pattern of the first outdoor heat exchanger 7a and the second outdoor heat exchanger 7b. FIG. 3 is a conceptual diagram showing an image of the defrosting state during the defrosting operation. The refrigerant circuit configuration and operation of the air conditioner 100 will be described with reference to FIGS. The air conditioner 100 performs a cooling operation or a heating operation using a refrigeration cycle (heat pump cycle) for circulating a refrigerant. In addition, in the following drawings including FIG. 1, the relationship of the size of each component may be different from the actual one.

図１に示すように、空気調和機１００は、圧縮機１と、流路切替装置（流路切替装置２ａ、流路切替装置２ｂ及び流路切替装置２ｃ）と、室内熱交換器３と、減圧装置（減圧装置４ａ、減圧装置４ｂ及び減圧装置４ｃ）と、電磁弁（電磁弁６ａ及び電磁弁６ｂ）と、第１室外熱交換器７ａと、第２室外熱交換器７ｂと、を冷媒配管１５、第１バイパス管１６及び第２バイパス管１７を介して接続した閉回路（冷媒回路）を備えている。そして、冷媒回路内には、冷媒が封入されている。つまり、空気調和機１００は、冷媒回路に冷媒を循環させることによって、冷房運転又は暖房運転することができるようになっている。 As shown in FIG. 1, the air conditioner 100 includes a compressor 1, a flow switching device (a flow switching device 2a, a flow switching device 2b, and a flow switching device 2c), an indoor heat exchanger 3, The decompression device (the decompression device 4a, the decompression device 4b, and the decompression device 4c), the solenoid valve (the solenoid valve 6a and the solenoid valve 6b), the first outdoor heat exchanger 7a, and the second outdoor heat exchanger 7b are refrigerant. A closed circuit (refrigerant circuit) connected via a pipe 15, a first bypass pipe 16 and a second bypass pipe 17 is provided. A refrigerant is sealed in the refrigerant circuit. That is, the air conditioner 100 can perform a cooling operation or a heating operation by circulating the refrigerant in the refrigerant circuit.

第１バイパス管１６は、圧縮機１の吐出側から冷媒配管１５を分岐させて第１室外熱交換器７ａ及び第２室外熱交換器７ｂに接続させる冷媒配管である。第２バイパス管１７は、圧縮機１の吸入側の冷媒配管１５を分岐させて第１室外熱交換器７ａ及び第２室外熱交換器７ｂに接続させる冷媒配管である。また、第１室外熱交換器７ａと第２室外熱交換器７ｂとは、冷媒配管１５、第１バイパス管１６及び第２バイパス管１７によって室内熱交換器３に対して並列となるように接続されている。第１バイパス管１６及び第２バイパス管１７は、流路切替装置２ｂ及び流路切替装置２ｃに接続されている。 The first bypass pipe 16 is a refrigerant pipe that branches the refrigerant pipe 15 from the discharge side of the compressor 1 and connects it to the first outdoor heat exchanger 7a and the second outdoor heat exchanger 7b. The second bypass pipe 17 is a refrigerant pipe that branches the refrigerant pipe 15 on the suction side of the compressor 1 and connects it to the first outdoor heat exchanger 7a and the second outdoor heat exchanger 7b. The first outdoor heat exchanger 7a and the second outdoor heat exchanger 7b are connected in parallel to the indoor heat exchanger 3 by the refrigerant pipe 15, the first bypass pipe 16, and the second bypass pipe 17. Has been. The first bypass pipe 16 and the second bypass pipe 17 are connected to the flow path switching device 2b and the flow path switching device 2c.

図２で詳細に説明するが、第１室外熱交換器７ａ及び第２室外熱交換器７ｂは、内部を導通する伝熱管が２つのパス（室外熱交換器パスａ、室外熱交換器パスｂ）となるように分割されて構成されている。図１では、第１室外熱交換器７ａ及び第２室外熱交換器７ｂが２つに分割されている場合を概念的に図示している。つまり、第１室外熱交換器７ａが分割熱交換器（第１熱交換器）８ａ及び分割熱交換器（第２熱交換器）９ａで、第２室外熱交換器７ｂが分割熱交換器（第１熱交換器）８ｂ及び分割熱交換器（第２熱交換器）９ｂで、それぞれ構成されている。 As will be described in detail with reference to FIG. 2, the first outdoor heat exchanger 7a and the second outdoor heat exchanger 7b have two paths (the outdoor heat exchanger path a and the outdoor heat exchanger path b) through which the heat transfer pipes are electrically connected. ) To be divided. In FIG. 1, the case where the 1st outdoor heat exchanger 7a and the 2nd outdoor heat exchanger 7b are divided | segmented into two is shown notionally. That is, the first outdoor heat exchanger 7a is a split heat exchanger (first heat exchanger) 8a and a split heat exchanger (second heat exchanger) 9a, and the second outdoor heat exchanger 7b is a split heat exchanger ( The first heat exchanger 8b and the divided heat exchanger (second heat exchanger) 9b are respectively configured.

分割熱交換器８ａには、流路切替装置２ｂを介して第１バイパス管１６及び第２バイパス管１７が接続されている。同様に、分割熱交換器８ｂには、流路切替装置２ｃを介して第１バイパス管１６及び第２バイパス管１７が接続されている。また、分割熱交換器９ａ及び分割熱交換器９ｂは、暖房運転時における冷媒流通方向において、流路切替装置２ａの上流側となるように接続されている。以下の説明において、分割熱交換器８ａ及び分割熱交換器８ｂに冷媒を流通させるパスを室外熱交換器パスａと、分割熱交換器９ａ及び分割熱交換器９ｂに冷媒を流通させるパスを室外熱交換器パスｂと、それぞれ称するものとする。 A first bypass pipe 16 and a second bypass pipe 17 are connected to the divided heat exchanger 8a via a flow path switching device 2b. Similarly, the 1st bypass pipe 16 and the 2nd bypass pipe 17 are connected to the division | segmentation heat exchanger 8b via the flow-path switching apparatus 2c. Further, the divided heat exchanger 9a and the divided heat exchanger 9b are connected to be upstream of the flow path switching device 2a in the refrigerant flow direction during the heating operation. In the following description, the outdoor heat exchanger path a is the path through which the refrigerant flows through the divided heat exchanger 8a and the divided heat exchanger 8b, and the outdoor path through which the refrigerant flows through the divided heat exchanger 9a and the divided heat exchanger 9b. These are referred to as heat exchanger paths b, respectively.

圧縮機１は、冷媒配管１５を流れる冷媒を吸入し、その冷媒を圧縮して高温・高圧の状態とするものであり、たとえば容量制御可能なインバータ圧縮機等で構成するとよい。四方弁等で構成された流路切替装置２ａは、圧縮機１の吐出側に設けられており、空気調和機１００の運転に応じて圧縮機１から吐出された冷媒の流れを切り替えるものである。四方弁等で構成された流路切替装置２ｂは、暖房運転時における冷媒流通方向対において、分割熱交換器８ａの下流側に配置され、冷媒の流れを圧縮機１の吐出側又は吸入側に切り替えるものである。四方弁等で構成された流路切替装置２ｃは、暖房運転時における冷媒流通方向対において、分割熱交換器８ｂの下流側に配置され、冷媒の流れを圧縮機１の吐出側又は吸入側に切り替えるものである。 The compressor 1 sucks the refrigerant flowing through the refrigerant pipe 15 and compresses the refrigerant to be in a high temperature / high pressure state. For example, the compressor 1 may be composed of an inverter compressor capable of capacity control. The flow path switching device 2 a configured by a four-way valve or the like is provided on the discharge side of the compressor 1 and switches the flow of the refrigerant discharged from the compressor 1 according to the operation of the air conditioner 100. . The flow path switching device 2b configured by a four-way valve or the like is disposed on the downstream side of the divided heat exchanger 8a in the refrigerant flow direction pair during heating operation, and the refrigerant flow is directed to the discharge side or suction side of the compressor 1. It is to switch. The flow path switching device 2c configured by a four-way valve or the like is disposed on the downstream side of the divided heat exchanger 8b in the refrigerant flow direction pair during heating operation, and the refrigerant flow is directed to the discharge side or suction side of the compressor 1. It is to switch.

室内熱交換器３は、冷房運転時には蒸発器、暖房運転時には凝縮器（又は放熱器）として機能し、冷媒と室内送風機５により供給される空気との間で熱交換を行なうものである。減圧装置４ａは、暖房運転時における冷媒流通方向対において、室内熱交換器３の下流側に配置され、冷媒配管１５を導通する冷媒を減圧して膨張させるものである。減圧装置４ｂは、暖房運転時における冷媒流通方向対において、減圧装置４ａの下流側かつ室外熱交換器７ａの上流側に配置され、冷媒配管１５を導通する冷媒を減圧して膨張させるものである。減圧装置４ｃは、暖房運転時における冷媒流通方向対において、減圧装置４ａの下流側かつ室外熱交換器７ｂの上流側に配置され、冷媒配管１５を導通する冷媒を減圧して膨張させるものである。 The indoor heat exchanger 3 functions as an evaporator during the cooling operation and functions as a condenser (or a radiator) during the heating operation, and performs heat exchange between the refrigerant and the air supplied by the indoor blower 5. The decompression device 4a is disposed downstream of the indoor heat exchanger 3 in the refrigerant flow direction pair during heating operation, and decompresses and expands the refrigerant that is conducted through the refrigerant pipe 15. The decompression device 4b is disposed on the downstream side of the decompression device 4a and the upstream side of the outdoor heat exchanger 7a in the refrigerant flow direction pair during heating operation, and decompresses and expands the refrigerant that is conducted through the refrigerant pipe 15. . The decompression device 4c is disposed on the downstream side of the decompression device 4a and the upstream side of the outdoor heat exchanger 7b in the refrigerant flow direction pair during heating operation, and decompresses and expands the refrigerant that is conducted through the refrigerant pipe 15. .

なお、図１では、減圧装置４ａを設置した場合を例に示しているが、これに限定するものではなく、設置されなくてもよい。ただし、減圧装置４ａは、複数台の室内熱交換器３が並列に接続される空気調和機においては、それぞれの室内熱交換器３の冷媒流量を調節するのに必要である。減圧装置４ｂ及び減圧装置４ｃは、暖房運転時には、並列接続された複数台の室外熱交換器（室外熱交換器７ａ、室外熱交換器７ｂ）の冷媒流量を調節するために必要である。これらの減圧装置は、たとえば電子式の膨張弁等で構成するとよい。 In addition, in FIG. 1, although the case where the decompression device 4a is installed is shown as an example, it is not limited to this and may not be installed. However, the decompression device 4a is necessary for adjusting the refrigerant flow rate of each indoor heat exchanger 3 in an air conditioner in which a plurality of indoor heat exchangers 3 are connected in parallel. The decompression device 4b and the decompression device 4c are necessary for adjusting the refrigerant flow rates of a plurality of outdoor heat exchangers (the outdoor heat exchanger 7a and the outdoor heat exchanger 7b) connected in parallel during the heating operation. These pressure reducing devices may be constituted by electronic expansion valves, for example.

電磁弁（開閉弁）６ａは、減圧装置４ｂと分割熱交換器９ａとの間に設置され、開閉制御されることによって、分割熱交換器９ａに冷媒を流通させるかどうかの選択のために用いられるものである。電磁弁（開閉弁）６ｂは、減圧装置４ｃと分割熱交換器９ｂとの間に設置され、開閉制御されることによって、分割熱交換器９ｂに冷媒を流通させるかどうかの選択のために用いられるものである。第１室外熱交換器７ａは、冷房運転時には凝縮器（又は放熱器）、暖房運転時には蒸発器として機能し、冷媒と第１室外送風機１０ａにより供給される空気との間で熱交換を行なうものである。第２室外熱交換器７ｂの近傍には、それぞれ室内送風機５、第１室外送風機１０ａ、第２室外送風機１０ｂが備えられており、それぞれの熱交換器に送風することで、熱交換を促進、調整している。 The electromagnetic valve (open / close valve) 6a is installed between the pressure reducing device 4b and the divided heat exchanger 9a, and is used for selecting whether to circulate the refrigerant through the divided heat exchanger 9a by being controlled to open and close. It is The electromagnetic valve (open / close valve) 6b is installed between the pressure reducing device 4c and the split heat exchanger 9b, and is used for selecting whether to circulate the refrigerant through the split heat exchanger 9b by being controlled to open and close. It is The first outdoor heat exchanger 7a functions as a condenser (or radiator) during cooling operation, and functions as an evaporator during heating operation, and performs heat exchange between the refrigerant and the air supplied by the first outdoor blower 10a. It is. In the vicinity of the second outdoor heat exchanger 7b, an indoor blower 5, a first outdoor blower 10a, and a second outdoor blower 10b are provided, respectively, and heat exchange is promoted by sending air to each heat exchanger. It is adjusting.

第１室外送風機１０ａは、第１室外熱交換器７ａの近傍に設置され、第１室外熱交換器７ａに空気を供給するものである。第２室外送風機１０ｂは、第２室外熱交換器７ｂの近傍に設置され、第２室外熱交換器７ｂに空気を供給するものである。また、空気調和機１００には、圧縮機１の駆動周波数、流路切替装置の切り替え、送風機（室内送風機５、第１室外送風機１０ａ及び第２室外送風機１０ｂ）の回転数、減圧装置の開度、電磁弁の開閉を制御するマイクロコンピュータ等で構成されている図示省略の制御装置が設けられている。 The 1st outdoor air blower 10a is installed in the vicinity of the 1st outdoor heat exchanger 7a, and supplies air to the 1st outdoor heat exchanger 7a. The second outdoor fan 10b is installed in the vicinity of the second outdoor heat exchanger 7b and supplies air to the second outdoor heat exchanger 7b. The air conditioner 100 also includes a drive frequency of the compressor 1, switching of the flow path switching device, the number of rotations of the blower (the indoor blower 5, the first outdoor blower 10a, and the second outdoor blower 10b), and the opening of the decompression device. In addition, a control device (not shown) configured by a microcomputer or the like for controlling opening and closing of the electromagnetic valve is provided.

ここで、空気調和機１００の冷房運転時の動作について説明する。
空気調和機１００が冷房運転を実行する際には、流路切替装置（流路切替装置２ａ、流路切替装置２ｂ及び流路切替装置２ｃ）が圧縮機１から吐出される冷媒のすべてを第１室外熱交換器７ａ（詳しくは、分割熱交換器８ａ）及び第２室外熱交換器７ｂ（詳しくは、分割熱交換器８ｂ）に流入させる冷媒回路となるように切り替えられる。また、電磁弁（電磁弁６ａ及び電磁弁６ｂ）は、開いた状態に設定される。このような状態で空気調和機１００の冷房運転が開始される。 Here, the operation | movement at the time of the cooling operation of the air conditioner 100 is demonstrated.
When the air conditioner 100 performs the cooling operation, the flow path switching device (the flow path switching device 2a, the flow path switching device 2b, and the flow path switching device 2c) removes all of the refrigerant discharged from the compressor 1. The refrigerant is switched to a refrigerant circuit that flows into the first outdoor heat exchanger 7a (specifically, the divided heat exchanger 8a) and the second outdoor heat exchanger 7b (specifically, the divided heat exchanger 8b). Further, the solenoid valves (the solenoid valve 6a and the solenoid valve 6b) are set in an open state. In such a state, the cooling operation of the air conditioner 100 is started.

空気調和機１００が運転を開始すると、まず圧縮機１が駆動される。そして、圧縮機１で圧縮された高温・高圧の冷媒は、圧縮機１から吐出され流路切替装置を介して第１室外熱交換器７ａの分割熱交換器８ａと、第２室外熱交換器７ｂの分割熱交換器８ｂに流入する。分割熱交換器８ａ及び分割熱交換器８ｂでは、流入した高温・高圧の冷媒が、第１室外送風機１０ａ及び第２室外送風機１０ｂから供給される空気（外気）に放熱しながら凝縮し、低温・高圧の冷媒となり、第１室外熱交換器７ａ及び第２室外熱交換器７ｂから流出する。 When the air conditioner 100 starts operation, the compressor 1 is first driven. The high-temperature and high-pressure refrigerant compressed by the compressor 1 is discharged from the compressor 1 and the divided heat exchanger 8a of the first outdoor heat exchanger 7a and the second outdoor heat exchanger via the flow path switching device. It flows into the divided heat exchanger 8b of 7b. In the divided heat exchanger 8a and the divided heat exchanger 8b, the flowing high-temperature and high-pressure refrigerant is condensed while dissipating heat to the air (outside air) supplied from the first outdoor fan 10a and the second outdoor fan 10b. It becomes a high-pressure refrigerant and flows out of the first outdoor heat exchanger 7a and the second outdoor heat exchanger 7b.

第１室外熱交換器７ａ及び第２室外熱交換器７ｂから流出した冷媒は、第１室外熱交換器７ａ及び第２室外熱交換器７ｂに隣接して設置された減圧装置４ｂ及び減圧装置４ｃのそれぞれで減圧される。このとき、減圧装置４ｂ及び減圧装置４ｃの開度によって、第１室外熱交換器７ａ及び第２室外熱交換器７ｂの出口側の冷媒の過冷却度を所定値に調整する。減圧装置４ｂ及び減圧装置４ｃで減圧された冷媒は、さらに減圧装置４ａで減圧され、低圧二相状態となる。この冷媒は、室内熱交換器３に流入し、室内送風機５から供給される空気（室内空気）から吸熱することで蒸発し、低圧のガス冷媒となって圧縮機１に再度吸入される。 The refrigerant that has flowed out of the first outdoor heat exchanger 7a and the second outdoor heat exchanger 7b is removed from the decompression device 4b and the decompression device 4c that are installed adjacent to the first outdoor heat exchanger 7a and the second outdoor heat exchanger 7b. Each of these is depressurized. At this time, the degree of supercooling of the refrigerant on the outlet side of the first outdoor heat exchanger 7a and the second outdoor heat exchanger 7b is adjusted to a predetermined value by the opening degree of the pressure reducing device 4b and the pressure reducing device 4c. The refrigerant decompressed by the decompression device 4b and the decompression device 4c is further decompressed by the decompression device 4a to be in a low-pressure two-phase state. This refrigerant flows into the indoor heat exchanger 3, evaporates by absorbing heat from the air (indoor air) supplied from the indoor blower 5, becomes a low-pressure gas refrigerant, and is sucked into the compressor 1 again.

次に、空気調和機１００の暖房運転時の動作について説明する。
空気調和機１００が冷房運転を実行する際には、流路切替装置（流路切替装置２ａ、流路切替装置２ｂ及び流路切替装置２ｃ）が圧縮機１から吐出される冷媒のすべてを室内熱交換器３に流入させる冷媒回路となるように切り替えられる。また、電磁弁（電磁弁６ａ及び電磁弁６ｂ）は、開いた状態に設定される。このような状態で空気調和機１００の暖房運転が開始される。 Next, the operation | movement at the time of the heating operation of the air conditioner 100 is demonstrated.
When the air conditioner 100 performs the cooling operation, the flow path switching device (the flow path switching device 2a, the flow path switching device 2b, and the flow path switching device 2c) removes all of the refrigerant discharged from the compressor 1 indoors. The refrigerant circuit is switched so as to flow into the heat exchanger 3. Further, the solenoid valves (the solenoid valve 6a and the solenoid valve 6b) are set in an open state. In such a state, the heating operation of the air conditioner 100 is started.

空気調和機１００が運転を開始すると、まず圧縮機１が駆動される。そして、圧縮機１で圧縮された高温・高圧の冷媒は、圧縮機１から吐出され流路切替装置２ａを介して室内熱交換器３に流入する。室内熱交換器３では、流入した高温・高圧の冷媒が、室内送風機５から供給される空気（室内空気）に放熱しながら凝縮し、低温・高圧の冷媒となり、室内熱交換器３から流出する。 When the air conditioner 100 starts operation, the compressor 1 is first driven. The high-temperature and high-pressure refrigerant compressed by the compressor 1 is discharged from the compressor 1 and flows into the indoor heat exchanger 3 through the flow path switching device 2a. In the indoor heat exchanger 3, the flowing high-temperature / high-pressure refrigerant is condensed while dissipating heat to the air (indoor air) supplied from the indoor blower 5, becomes a low-temperature / high-pressure refrigerant, and flows out of the indoor heat exchanger 3. .

室内熱交換器３から流出した冷媒は、減圧装置４ａで減圧される。このとき、減圧装置４ａの開度によって、室内熱交換器３の出口側の冷媒の過冷却度を所定値に調整する。減圧装置４ａで減圧された冷媒は、さらに減圧装置４ｂ及び減圧装置４ｃで減圧され、低圧二相状態となる。この冷媒は、第１室外熱交換器７ａ及び第２室外熱交換器７ｂに流入し、第１室外送風機１０ａ及び第２室外送風機１０ｂのそれぞれから供給される空気（外気）から吸熱することで蒸発し、低圧のガス冷媒となって圧縮機１に再度吸入される。 The refrigerant flowing out of the indoor heat exchanger 3 is decompressed by the decompression device 4a. At this time, the degree of supercooling of the refrigerant on the outlet side of the indoor heat exchanger 3 is adjusted to a predetermined value by the opening of the decompression device 4a. The refrigerant decompressed by the decompression device 4a is further decompressed by the decompression device 4b and the decompression device 4c, and enters a low-pressure two-phase state. This refrigerant flows into the first outdoor heat exchanger 7a and the second outdoor heat exchanger 7b, and evaporates by absorbing heat from the air (outside air) supplied from each of the first outdoor fan 10a and the second outdoor fan 10b. Then, it becomes a low-pressure gas refrigerant and is sucked into the compressor 1 again.

この暖房運転時に外気が低温であると、第１室外熱交換器７ａ及び第２室外熱交換器７ｂでの蒸発温度が０℃以下になり、第１室外熱交換器７ａ及び第２室外熱交換器７ｂに霜が付着する着霜状態が発生する。一般に、熱交換器が着霜すると、熱交換器を構成しているフィンに付着した霜が通風抵抗となり通風量が低下し、また霜が熱抵抗となることから伝熱性能も低下する。このような着霜を伴う運転状況下では、所定間隔で除霜運転（デフロスト運転）を行ない、熱交換器に付着した霜を融解して除去することが一般的となっている。 If the outside air is at a low temperature during the heating operation, the evaporating temperature in the first outdoor heat exchanger 7a and the second outdoor heat exchanger 7b becomes 0 ° C. or lower, and the first outdoor heat exchanger 7a and the second outdoor heat exchange. A frosting state occurs in which frost adheres to the vessel 7b. In general, when the heat exchanger is frosted, the frost attached to the fins constituting the heat exchanger becomes a ventilation resistance, the ventilation rate is reduced, and the frost becomes a thermal resistance, so that the heat transfer performance is also lowered. Under such operating conditions involving frost formation, it is common to perform a defrosting operation (defrosting operation) at predetermined intervals to melt and remove the frost attached to the heat exchanger.

ここで、空気調和機１００が実行する除霜運転について説明する。なお、ここでは、第１室外熱交換器７ａの除霜運転について説明するが、第２室外熱交換器７ｂの除霜運転についても動作は同様である。空気調和機１００（詳しくは、制御装置）は、着霜を生じる運転状況下において、たとえば冷媒の蒸発温度と外気との温度差が所定値より拡大した場合等のように着霜量の基準値以上の増加を検知する手段によって、除霜運転の必要性を判定するようになっている。そして、空気調和機１００は、除霜運転が必要であると判定すると、除霜運転を実行する。 Here, the defrost operation which the air conditioner 100 performs is demonstrated. Although the defrosting operation of the first outdoor heat exchanger 7a will be described here, the operation is the same for the defrosting operation of the second outdoor heat exchanger 7b. The air conditioner 100 (specifically, the control device) is a reference value for the amount of frost formation, for example, when the temperature difference between the evaporating temperature of the refrigerant and the outside air is larger than a predetermined value under an operating condition in which frost formation occurs. The necessity for defrosting operation is determined by means for detecting the above increase. And if it determines with the air conditioner 100 requiring defrost operation, it will perform defrost operation.

空気調和機１００が除霜運転を実行する際には、流路切替装置２ｂを圧縮機１から吐出される高温・高圧の冷媒の一部を室外熱交換器パスａに流通、つまり分割熱交換器８ａに流入するように切り替え、電磁弁６ａを閉じ（つまり、分割熱交換器９ａをオフサイクルにするということ）、第１室外送風機１０ａを停止する。このような冷媒回路において、圧縮機１から吐出された高温・高圧ガスが室外熱交換器パスａを流通し、分割熱交換器８ａに流入する。そのため、分割熱交換器８ａに付着した霜を確実に除霜することができる。 When the air conditioner 100 performs the defrosting operation, a part of the high-temperature and high-pressure refrigerant discharged from the compressor 1 is passed through the flow path switching device 2b to the outdoor heat exchanger path a, that is, divided heat exchange. The solenoid valve 6a is closed (that is, the divided heat exchanger 9a is turned off), and the first outdoor blower 10a is stopped. In such a refrigerant circuit, the high-temperature and high-pressure gas discharged from the compressor 1 flows through the outdoor heat exchanger path a and flows into the divided heat exchanger 8a. Therefore, the frost adhering to the division | segmentation heat exchanger 8a can be defrosted reliably.

また、電磁弁６ａを閉じているために、室外熱交換器パスｂ、つまり分割熱交換器９ａに冷媒が流入することがなく、室外熱交換器パスａからの熱伝導と、霜が融解して生成した高温の水の滴下とによって、分割熱交換器９ａの除霜も可能となる。したがって、分割熱交換器８ａを除霜することで得られた融解水が持つ熱量を利用して、分割熱交換器９ａの除霜を行うため、除霜に必要な熱量を最小にすることができることになる。なお、第１室外熱交換器７ａ及び第２室外熱交換器７ｂにおいて、室外熱交換器パスａが最上部となるように各分割熱交換器が配置されている（図２及び図３参照）。 Further, since the solenoid valve 6a is closed, the refrigerant does not flow into the outdoor heat exchanger path b, that is, the divided heat exchanger 9a, and heat conduction from the outdoor heat exchanger path a and frost are melted. The defrosting of the divided heat exchanger 9a is also possible by the dripping of the high-temperature water generated in this way. Therefore, since the defrosting of the divided heat exchanger 9a is performed using the amount of heat of the molten water obtained by defrosting the divided heat exchanger 8a, the amount of heat necessary for defrosting can be minimized. It will be possible. In the first outdoor heat exchanger 7a and the second outdoor heat exchanger 7b, the divided heat exchangers are arranged so that the outdoor heat exchanger path a is at the top (see FIGS. 2 and 3). .

このときの減圧装置４ｂ及び減圧装置４ｃの制御について説明する。
除霜運転開始直後、圧縮機１から室内熱交換器３へ流入する冷媒量が減少し、高圧が低下する。高圧の低下に伴い、凝縮温度も低下するため、暖房能力が低下する。過度の暖房能力の低下が起こると、室内温度が低下し、居室者の快適性を損ねることになる。そこで、空気調和機１００では、減圧装置４ｂを、高圧を維持するよう動作させる。また、減圧装置４ｃを、蒸発器として機能する熱交換器の出口状態もしくは圧縮機１の吸入状態を常に所定値とするよう動作させる。これにより、圧縮機１の吸入が過度の液バックとなることがなく、信頼性が向上することになる。 Control of the decompression device 4b and the decompression device 4c at this time will be described.
Immediately after the start of the defrosting operation, the amount of refrigerant flowing from the compressor 1 into the indoor heat exchanger 3 decreases, and the high pressure decreases. As the high pressure decreases, the condensation temperature also decreases, so the heating capacity decreases. If the heating capacity is excessively lowered, the room temperature is lowered and the comfort of the occupants is impaired. Therefore, in the air conditioner 100, the decompression device 4b is operated to maintain a high pressure. Further, the decompression device 4c is operated so that the outlet state of the heat exchanger functioning as an evaporator or the suction state of the compressor 1 is always set to a predetermined value. Thereby, the suction | inhalation of the compressor 1 does not become an excessive liquid back | bag, and reliability improves.

また、空気調和機１００では、図２に示すように、第１室外熱交換器７ａ及び第２室外熱交換器７ｂの最上部が、室外熱交換器パスａ（分割熱交換器８ａ、分割熱交換器８ｂ）となっており、室外熱交換器パスａと室外熱交換器パスｂ（分割熱交換器９ａ、分割熱交換器９ｂ）とが上下方向に交互に積層されている。空気調和機１００では、第１室外熱交換器７ａ及び第２室外熱交換器７ｂが、除霜時に室外熱交換器パスａの熱を利用して熱伝導で室外熱交換器パスｂの除霜を行なうため、各分割熱交換器が一体的に成形されている必要がある。なお、分割熱交換器の積層数は少なくとも２段あればよい。 Further, in the air conditioner 100, as shown in FIG. 2, the uppermost portions of the first outdoor heat exchanger 7a and the second outdoor heat exchanger 7b are connected to the outdoor heat exchanger path a (divided heat exchanger 8a, divided heat The outdoor heat exchanger path a and the outdoor heat exchanger path b (the divided heat exchanger 9a and the divided heat exchanger 9b) are alternately stacked in the vertical direction. In the air conditioner 100, the first outdoor heat exchanger 7a and the second outdoor heat exchanger 7b use the heat of the outdoor heat exchanger path a during defrosting to conduct defrosting of the outdoor heat exchanger path b by heat conduction. Therefore, each divided heat exchanger needs to be formed integrally. The number of stacked heat exchangers may be at least two.

除霜運転中の第１室外熱交換器７ａでの除霜状態のイメージを図３に基づいて説明する。なお、第２室外熱交換器７ｂでも同様であることは言うまでもない。空気調和機１００では、室外熱交換器の除霜運転が実行されると、室外熱交換器パスａに圧縮機１からの吐出冷媒を流通させる。そうすると、室外熱交換器パスａが通されている分割熱交換器８ａで除霜が実行される。そのため、分割熱交換器８ａに付着した霜を確実に除霜することができる。そして、室外熱交換器パスａからの熱伝導（矢印Ａ）と、霜が融解して生成した高温の水の滴下（矢印Ｂ）とによって、分割熱交換器９ａの除霜も可能となる。 An image of the defrosting state in the first outdoor heat exchanger 7a during the defrosting operation will be described with reference to FIG. Needless to say, the same applies to the second outdoor heat exchanger 7b. In the air conditioner 100, when the defrosting operation of the outdoor heat exchanger is executed, the refrigerant discharged from the compressor 1 is circulated through the outdoor heat exchanger path a. Then, defrosting is performed in the divided heat exchanger 8a through which the outdoor heat exchanger path a is passed. Therefore, the frost adhering to the division | segmentation heat exchanger 8a can be defrosted reliably. And the defrosting of the division | segmentation heat exchanger 9a is also attained by the heat conduction (arrow A) from the outdoor heat exchanger path | pass a, and dripping of the high temperature water which the frost melt | dissolved and produced | generated (arrow B).

図４は、第１室外熱交換器７ａ及び第２室外熱交換器７ｂの分割パターンの他の一例を示す斜視図である。図２では、室外熱交換器パスａと室外熱交換器パスｂとが高さ方向に交互に、つまり分割熱交換器８ａ（又は分割熱交換器８ｂ）と分割熱交換器９ａ（又は分割熱交換器９ｂ）とが上下に交互に配置されるように室外熱交換器（第１室外熱交換器７ａ及び第２室外熱交換器７ｂ）を構成した場合を例に示したが、図４では、室外熱交換器パスａと室外熱交換器パスｂとを高さ方向に加え奥行き（空気の流れ）方向にも交互に配置されるように構成した状態を例に示している。 FIG. 4 is a perspective view showing another example of the division pattern of the first outdoor heat exchanger 7a and the second outdoor heat exchanger 7b. In FIG. 2, the outdoor heat exchanger path a and the outdoor heat exchanger path b are alternately arranged in the height direction, that is, the divided heat exchanger 8a (or divided heat exchanger 8b) and the divided heat exchanger 9a (or divided heat). Although the case where the outdoor heat exchangers (the first outdoor heat exchanger 7a and the second outdoor heat exchanger 7b) are configured so that the exchangers 9b) are alternately arranged vertically is shown in FIG. An example is shown in which the outdoor heat exchanger path a and the outdoor heat exchanger path b are alternately arranged in the depth direction (air flow) direction in addition to the height direction.

具体的には、第１室外熱交換器７ａと第２室外熱交換器７ｂとのそれぞれのパス構成として、室外熱交換器パスａと室外熱交換器パスｂとを高さ方向に千鳥状に配置してもよい。つまり、第１室外熱交換器７ａにおいて、分割熱交換器８ａと分割熱交換器９ａとが奥行き（空気の流れ）方向に２列に配置され、高さ方向に千鳥状に配置されている。同様に、第１室外熱交換器７ｂにおいて、分割熱交換器８ｂと分割熱交換器９ｂとが奥行き（空気の流れ）方向に２列に配置され、高さ方向に千鳥状に配置されている。 Specifically, as the respective path configurations of the first outdoor heat exchanger 7a and the second outdoor heat exchanger 7b, the outdoor heat exchanger path a and the outdoor heat exchanger path b are staggered in the height direction. You may arrange. That is, in the first outdoor heat exchanger 7a, the divided heat exchanger 8a and the divided heat exchanger 9a are arranged in two rows in the depth (air flow) direction, and are arranged in a staggered pattern in the height direction. Similarly, in the first outdoor heat exchanger 7b, the divided heat exchanger 8b and the divided heat exchanger 9b are arranged in two rows in the depth (air flow) direction and arranged in a staggered manner in the height direction. .

このように室外熱交換器を構成しても、図２に示した室外熱交換器の構成と同様に、除霜時に室外熱交換器パスａ（分割熱交換器８ａ、分割熱交換器８ｂ）の熱を利用して熱伝導で室外熱交換器パスｂ（分割熱交換器９ａ、分割熱交換器９ｂ）の除霜を行なうことができる。なお、図２では、室外熱交換器パスａを最上部に配置した場合を例に説明したが、少なくとも図４に示したように風上側の室外熱交換器パスａが最上部に配置されていればよい。 Even if the outdoor heat exchanger is configured in this manner, the outdoor heat exchanger path a (the divided heat exchanger 8a and the divided heat exchanger 8b) is used during defrosting, similarly to the configuration of the outdoor heat exchanger shown in FIG. The outdoor heat exchanger path b (split heat exchanger 9a, split heat exchanger 9b) can be defrosted by heat conduction using the heat of the heat. In FIG. 2, the case where the outdoor heat exchanger path a is arranged at the top is described as an example, but at least the windward outdoor heat exchanger path a is arranged at the top as shown in FIG. 4. Just do it.

図５は、冷房運転時における室外熱交換器出口の過冷却度とＣＯＰ（成績係数）及び伝熱管の液部容積との関係を示したグラフである。図６は、室外熱交換器の分割配分の決定法の流れを示すフローチャートである。図５及び図６に基づいて、第１室外熱交換器７ａ及び第２室外熱交換器７ｂの室外熱交換器パスａ（分割熱交換器８ａ、分割熱交換器８ｂ）の容積の決定の仕方について説明する。図５では、縦軸に冷房運転時のＣＯＰ及び伝熱管内の液部容積を、横軸に過冷却度を、それぞれ示している。また、線（ア）がＣＯＰを、線（イ）が伝熱管の液部容積を、それぞれ表している。 FIG. 5 is a graph showing the relationship between the degree of supercooling at the outlet of the outdoor heat exchanger, the COP (coefficient of performance), and the liquid volume of the heat transfer tube during cooling operation. FIG. 6 is a flowchart showing the flow of the method for determining the divisional distribution of the outdoor heat exchanger. Based on FIGS. 5 and 6, how to determine the volumes of the outdoor heat exchanger paths a (split heat exchanger 8 a and split heat exchanger 8 b) of the first outdoor heat exchanger 7 a and the second outdoor heat exchanger 7 b. Will be described. In FIG. 5, the vertical axis indicates the COP and the liquid volume in the heat transfer tube during the cooling operation, and the horizontal axis indicates the degree of supercooling. Further, line (A) represents COP, and line (A) represents liquid volume of the heat transfer tube.

図５から、冷房運転で冷媒回路内に封入冷媒量を増やしていくと、室外熱交換器出口の過冷却度が増加していき、室外熱交換器出口の過冷却度が所定値に達したところでＣＯＰが最大となる点が現れることがわかる。そこで、この過冷却度が所定値になるときの冷媒量を冷媒回路内の封入冷媒量として決定する（図６で示すステップＳ１０１）。また、室外熱交換器出口の過冷却度が大きくなるにつれて、第１室外熱交換器７ａ及び第２室外熱交換器７ｂを合わせた全室外熱交換器での伝熱管内容積で液冷媒が占める割合が大きくなっていく。 From FIG. 5, when the amount of refrigerant enclosed in the refrigerant circuit is increased in the cooling operation, the degree of supercooling at the outdoor heat exchanger outlet increases, and the degree of supercooling at the outdoor heat exchanger outlet reaches a predetermined value. By the way, it can be seen that a point where the COP becomes maximum appears. Therefore, the amount of refrigerant when the degree of supercooling reaches a predetermined value is determined as the amount of refrigerant enclosed in the refrigerant circuit (step S101 shown in FIG. 6). Further, as the degree of supercooling at the outlet of the outdoor heat exchanger increases, the liquid refrigerant occupies the volume of the heat transfer tube in the entire outdoor heat exchanger including the first outdoor heat exchanger 7a and the second outdoor heat exchanger 7b. The ratio will increase.

図５から、ＣＯＰが最大となる過冷却度では、全室外熱交換器の伝熱管内容積で液冷媒が占める割合が２０〜３０％程度となっていることがわかる。つまり、この全室外熱交換器の伝熱管内容積の２０〜３０％は、暖房と除霜の混在運転時に冷媒が除霜を行なっている熱交換器内に溜まり込んでも冷媒不足とならない容積となる（図６で示すステップＳ１０２）。これにより、室外熱交換器パスａ（分割熱交換器８ａ、分割熱交換器８ｂ）の内容積は、第１室外熱交換器７ａもしくは第２室外熱交換器７ｂの伝熱管内容積の最大６０％程度まで許容されることになる（図６で示すステップＳ１０３）。 From FIG. 5, it can be seen that at the degree of supercooling at which COP is maximized, the ratio of the liquid refrigerant to the heat transfer tube inner volume of the outdoor heat exchanger is about 20 to 30%. That is, 20-30% of the heat transfer tube inner volume of this all-outdoor heat exchanger is such that the refrigerant does not become insufficient even if the refrigerant accumulates in the heat exchanger where defrosting is performed during mixed operation of heating and defrosting. (Step S102 shown in FIG. 6). Thus, the internal volume of the outdoor heat exchanger path a (the divided heat exchanger 8a and the divided heat exchanger 8b) is 60 at the maximum of the heat transfer tube inner volume of the first outdoor heat exchanger 7a or the second outdoor heat exchanger 7b. % Is allowed (step S103 shown in FIG. 6).

また、除霜をより確実に完了するために、除霜運転の最後に電磁弁６ａを開いて室外熱交換器パスｂ（分割熱交換器９ａ）にも圧縮機１からの高温・高圧冷媒を流入させるとよい。さらに、除霜完了の検知手段として、たとえば除霜を行なっている熱交換器の温度や除霜によって生じた融解水の温度を検知する方法や、フィン温度を検知する方法、光学センサーで検知する方法、もしくはこれらの方法の組み合わせ等を適用するとよい。 In order to complete the defrosting more reliably, the solenoid valve 6a is opened at the end of the defrosting operation, and the high-temperature / high-pressure refrigerant from the compressor 1 is also supplied to the outdoor heat exchanger path b (divided heat exchanger 9a). It is good to let it flow. Further, as a defrosting completion detection means, for example, a method of detecting the temperature of a heat exchanger performing defrosting or a temperature of molten water generated by defrosting, a method of detecting fin temperature, or an optical sensor is used. A method or a combination of these methods may be applied.

なお、第１室外熱交換器７ａと第２室外熱交換器７ｂとが同時に除霜運転に入ると、蒸発器となる熱交換器がなくなってしまう。このような状態を避けるために、暖房運転時に第１室外送風機１０ａと第２室外送風機１０ｂとの風量を変化させることで第１室外熱交換器７ａや第２室外熱交換器７ｂの着霜量を調節したり、減圧装置４ｂ及び／又は減圧装置４ｃの開度を制御することで第１室外熱交換器７ａや第２室外熱交換器７ｂの着霜量を調整したりするとよい。また、第１室外熱交換器７ａ又は第２室外熱交換器７ｂの除霜中に、空気への放熱を減少させ効率よく除霜を行なうために、第１室外熱交換器７ａ又は第２室外熱交換器７ｂを断熱幕等で覆ってもよい。 In addition, if the 1st outdoor heat exchanger 7a and the 2nd outdoor heat exchanger 7b start defrost operation simultaneously, the heat exchanger used as an evaporator will be lose | eliminated. In order to avoid such a state, the amount of frost formation on the first outdoor heat exchanger 7a and the second outdoor heat exchanger 7b is performed by changing the air volume of the first outdoor fan 10a and the second outdoor fan 10b during the heating operation. It is good to adjust the amount of frost formation of the 1st outdoor heat exchanger 7a and the 2nd outdoor heat exchanger 7b by adjusting the opening degree of the decompression device 4b and / or the decompression device 4c. Further, during the defrosting of the first outdoor heat exchanger 7a or the second outdoor heat exchanger 7b, the first outdoor heat exchanger 7a or the second outdoor space is used in order to reduce the heat radiation to the air and efficiently perform the defrosting. The heat exchanger 7b may be covered with a heat insulating curtain or the like.

さらに、第１室外熱交換器７ａ又は第２室外熱交換器７ｂの除霜中に、除霜を行なっている室外熱交換器で生じる融解水をできるだけ室外熱交換器パスａにおいて昇温してから室外熱交換器パスｂに流下させたほうがより確実に除霜可能であるため、室外熱交換器パスａにおいて、室外熱交換器パスｂよりもフィンピッチを狭くしたり、フィンの切り起こしを高くしたりして、融解水を十分に温まるまで保持するようにしてもよい。熱交換器の熱容量が小さいほうが外部の温度変化に対して熱交換器の温度変化も早くなるため、室外熱交換器パスｂにおいて、伝熱管の径を室外熱交換器パスａの伝熱管の径よりも細くしたり、フィンの外形を室外熱交換器パスａの外形よりも小さくしたり、フィンに穴を空けて熱容量を小さくしてもよい。 Further, during the defrosting of the first outdoor heat exchanger 7a or the second outdoor heat exchanger 7b, the temperature of the molten water generated in the outdoor heat exchanger performing the defrosting is increased as much as possible in the outdoor heat exchanger path a. Since it is possible to defrost more reliably by flowing down from the outdoor heat exchanger path b, the fin pitch in the outdoor heat exchanger path a is narrower than that of the outdoor heat exchanger path b, or the fins are cut and raised. Alternatively, the molten water may be kept high until it is sufficiently warmed. The smaller the heat capacity of the heat exchanger, the faster the temperature change of the heat exchanger with respect to the external temperature change. Therefore, in the outdoor heat exchanger path b, the diameter of the heat transfer tube is set to the diameter of the heat transfer tube of the outdoor heat exchanger path a. The heat capacity may be reduced by making the fin thinner, making the outer shape of the fin smaller than the outer shape of the outdoor heat exchanger path a, or making a hole in the fin.

以上のように、実施の形態に係る空気調和機１００は、除霜運転時も室外熱交換器の一部（たとえば、分割熱交換器９ａ）を蒸発器として機能させたまま、室内熱交換器３と室外熱交換器の一部（たとえば、分割熱交換器８ａ）を凝縮器として運転可能であるため、除霜運転中も暖房運転を継続できる。つまり、除霜熱交換器（室外熱交換器パスａに通されている第１熱交換器）の内容積を小さくすることで、除霜時に除霜熱交換器に大量の冷媒が溜まり込むのを抑えることができるのである。そのため、冷媒不足を防止でき、室外熱交換器パスａを高温に加熱でき、効率的な除霜運転が実現できる。 As described above, the air conditioner 100 according to the embodiment allows the indoor heat exchanger to function while the part of the outdoor heat exchanger (for example, the divided heat exchanger 9a) functions as an evaporator even during the defrosting operation. 3 and a part of the outdoor heat exchanger (for example, the divided heat exchanger 8a) can be operated as a condenser, so that the heating operation can be continued even during the defrosting operation. That is, by reducing the internal volume of the defrost heat exchanger (the first heat exchanger passed through the outdoor heat exchanger path a), a large amount of refrigerant accumulates in the defrost heat exchanger during defrosting. Can be suppressed. Therefore, the refrigerant shortage can be prevented, the outdoor heat exchanger path a can be heated to a high temperature, and an efficient defrosting operation can be realized.

また、室外熱交換器パスａからの熱伝導によって室外熱交換器パスｂの除霜をも実行することができる。加えて、室外熱交換器パスａで除霜によって生じる加熱された融解水を室外熱交換器パスｂの除霜に利用することもでき、室外熱交換器パスｂに通されている第２熱交換器でも確実な除霜をすることができるとともに、除霜に必要とする熱量を小さくすることもできる。 Moreover, the defrosting of the outdoor heat exchanger path | pass b can also be performed by the heat conduction from the outdoor heat exchanger path | pass a. In addition, the heated molten water generated by defrosting in the outdoor heat exchanger path a can be used for defrosting the outdoor heat exchanger path b, and the second heat passed through the outdoor heat exchanger path b. The exchanger can perform defrosting reliably and can also reduce the amount of heat required for defrosting.

さらに、空気調和機１００が実行する除霜運転は、室外熱交換器の除霜を室外熱交換器の一部分のみを高温にすることで行うため、弁類（特に流路切替装置となる四方弁）等を節約でき、低コストとなる。さらに、空気調和機１００が実行する除霜運転は、蒸発器として機能する熱交換器に付随する減圧装置が圧縮機の吸入状態を適正に調整するため、一般の除霜運転のような過度の液バック状態になることなく、信頼性の高い空気調和機を提供することが可能となる。 Further, since the defrosting operation performed by the air conditioner 100 is performed by defrosting the outdoor heat exchanger by raising only a part of the outdoor heat exchanger to a high temperature, valves (particularly, a four-way valve serving as a flow path switching device) ) Etc., and the cost is low. Further, the defrosting operation performed by the air conditioner 100 is an excessive amount of defrosting operation as in a general defrosting operation because the decompression device associated with the heat exchanger functioning as an evaporator appropriately adjusts the suction state of the compressor. It is possible to provide a highly reliable air conditioner without entering the liquid back state.

なお、実施の形態では、空気調和機１００の冷媒回路内を循環する冷媒の種類を説明していないが、冷媒の種類を特に限定するものではなく、たとえば二酸化炭素や炭化水素、ヘリウム等のような自然冷媒、ＨＦＣ４１０ＡやＨＦＣ４０７Ｃ等の代替冷媒のような塩素を含まない冷媒、もしくは既存の製品に使用されているＲ２２やＲ１３４ａ等のフロン系冷媒のいずれでもよい。また、圧縮機１は、レシプロ、ロータリー、スクロール、あるいは、スクリュー等の各種タイプのいずれのものを用いてもよく、回転数可変可能のものでもよく、回転数固定のものでもよい。 In the embodiment, the type of the refrigerant circulating in the refrigerant circuit of the air conditioner 100 is not described, but the type of the refrigerant is not particularly limited. For example, carbon dioxide, hydrocarbon, helium, etc. A natural refrigerant, a refrigerant that does not contain chlorine such as an alternative refrigerant such as HFC410A and HFC407C, or a CFC-based refrigerant such as R22 and R134a used in existing products may be used. The compressor 1 may be any of various types such as a reciprocating, a rotary, a scroll, or a screw. The compressor 1 may be capable of changing the rotational speed or may be fixed.

実施の形態に係る空気調和機の冷媒回路構成の一例を示す概略構成図である。It is a schematic block diagram which shows an example of the refrigerant circuit structure of the air conditioner which concerns on embodiment. 室外熱交換器の分割パターンの一例を示す斜視図である。It is a perspective view which shows an example of the division | segmentation pattern of an outdoor heat exchanger. 除霜運転時の除霜状態をイメージ化して示す概念図である。It is a key map showing the defrosting state at the time of defrosting operation. 室外熱交換器の分割パターンの他の一例を示す斜視図である。It is a perspective view which shows another example of the division | segmentation pattern of an outdoor heat exchanger. 冷房運転時における室外熱交換器出口の過冷却度とＣＯＰ及び伝熱管の液部容積との関係を示したグラフである。It is the graph which showed the relationship between the supercooling degree of the outdoor heat exchanger exit at the time of air_conditionaing | cooling operation, and the liquid part volume of COP and a heat exchanger tube. 室外熱交換器の分割配分の決定法の流れを示すフローチャートである。It is a flowchart which shows the flow of the determination method of the division | segmentation distribution of an outdoor heat exchanger.

Explanation of symbols

１圧縮機、２ａ流路切替装置（第１流路切替装置）、２ｂ流路切替装置（第２流路切替装置）、２ｃ流路切替装置（第２流路切替装置）、３室内熱交換器、４ａ減圧装置（第１減圧装置）、４ｂ減圧装置（第２減圧装置）、４ｃ減圧装置（第２減圧装置）、５室内送風機、６ａ電磁弁（開閉弁）、６ｂ電磁弁（開閉弁）、７ａ室外熱交換器、７ｂ室外熱交換器、８ａ分割熱交換器（第１熱交換器）、８ｂ分割熱交換器（第１熱交換器）、９ａ分割熱交換器（第２熱交換器）、９ｂ分割熱交換器（第２熱交換器）、１０ａ第１室外送風機、１０ｂ第２室外送風機、１５冷媒配管、１６第１バイパス管、１７第２バイパス管、１００空気調和機。 DESCRIPTION OF SYMBOLS 1 Compressor, 2a Channel switching device (1st channel switching device), 2b Channel switching device (2nd channel switching device), 2c Channel switching device (2nd channel switching device), 3 Indoor heat exchange 4a Pressure reducing device (first pressure reducing device), 4b Pressure reducing device (second pressure reducing device), 4c Pressure reducing device (second pressure reducing device), 5 Indoor fan, 6a Solenoid valve (open / close valve), 6b Solenoid valve (open / close valve) ), 7a outdoor heat exchanger, 7b outdoor heat exchanger, 8a split heat exchanger (first heat exchanger), 8b split heat exchanger (first heat exchanger), 9a split heat exchanger (second heat exchange) ), 9b divided heat exchanger (second heat exchanger), 10a first outdoor fan, 10b second outdoor fan, 15 refrigerant pipe, 16 first bypass pipe, 17 second bypass pipe, 100 air conditioner.

Claims

A compressor, a first flow path switching device, an indoor heat exchanger, a first decompression device, and at least two outdoor heat exchanges provided in parallel to the indoor heat exchanger and the first decompression device. And an air conditioner having a refrigerant circuit connected to the air conditioner,
Each outdoor heat exchanger is
The first heat exchanger and the second heat exchanger through which different paths are passed are alternately arranged in the vertical direction,
A second flow path switching device for communicating with one end of a path passing through the first heat exchanger to a discharge side or a suction side of the compressor, and a second decompression device connected to the other end;
The air conditioner, wherein the first flow path switching device is connected to one end of a path passing through the second heat exchanger, and the second pressure reducing device is connected to the other end via an on-off valve.

The air conditioner according to claim 1, wherein the first heat exchanger and the second heat exchanger are arranged in at least two rows in the air flow direction.

The air conditioner according to claim 2, wherein each of the first heat exchanger and the second heat exchanger is arranged in a staggered manner in the vertical direction.

The air conditioner according to any one of claims 1 to 3, wherein the first heat exchanger and the second heat exchanger are integrally configured.

The air conditioner according to any one of claims 1 to 4, wherein a fin pitch of the first heat exchanger is narrower than a fin pitch of the second heat exchanger.

The air conditioner according to any one of claims 1 to 5, wherein the fins of the first heat exchanger are raised and raised higher than those of the second heat exchanger.

During defrosting operation,
The indoor heat exchanger functions as a condenser, the first heat exchanger of one of the outdoor heat exchangers functions as a condenser, and the other of the outdoor heat exchangers functions as an evaporator. The air conditioner according to any one of claims 1 to 6.

In the one outdoor heat exchanger,
The air conditioner according to claim 7, wherein the on-off valve is closed so that the refrigerant does not flow through the second heat exchanger.