JP2013079736A

JP2013079736A - Multilocular air conditioner

Info

Publication number: JP2013079736A
Application number: JP2011218602A
Authority: JP
Inventors: Yasuhiro Oka; 康弘岡; Hideya Tamura; 秀哉田村; Takahiro Matsunaga; 隆廣松永; Masatoshi Watanabe; 真寿渡邊; Keito Kawai; 圭人川合; Kotaro Toya; 廣太郎戸矢; Takeshi Nakajima; 健中島
Original assignee: Fujitsu General Ltd
Current assignee: Fujitsu General Ltd
Priority date: 2011-09-30
Filing date: 2011-09-30
Publication date: 2013-05-02

Abstract

PROBLEM TO BE SOLVED: To prevent an overflow of an accumulator in an outdoor unit including an operating compressor when a function of an outdoor heat exchanger is switched from a compressor to an evaporator when only a compressor provided in part of the outdoor units among the plurality of the outdoor units is operated.SOLUTION: The multilocular air conditioner 1 includes: three outdoor units 2a-2c equipped with compressors 21a-21c, outdoor heat exchangers 23a-23c, four-way valves 22a-22c, and accumulators 24a-24c; five indoor units 8a-8e including indoor heat exchangers 81a-81e; and a control means for controlling the three outdoor units 2a-2c. The control means stops the compressor which has been operated after starting the stopped compressor when the function of the outdoor heat exchangers 23a-23c is shifted from the compressor to the evaporator by the switching of the four-way valves 22a-22c when the outdoor unit including the stopped compressor among the three outdoor units 2a-2c is present.

Description

本発明は、複数の室外機と複数の室内機とを備える多室形空気調和装置に関する。 The present invention relates to a multi-room air conditioner including a plurality of outdoor units and a plurality of indoor units.

従来から、圧縮機と室外熱交換器と流路切換弁とアキュムレータとを備える複数の室外機と、室内熱交換器を備える複数の室内機とを、冷媒配管で接続して構成される多室形空気調和装置が知られている。この種の多室形空気調和装置の一例として、運転を行っている室内機全体の要求能力に応じて室内機の運転台数を変更する多室形空気調和装置がある（例えば、特許文献１参照）。 Conventionally, a multi-chamber configured by connecting a plurality of outdoor units including a compressor, an outdoor heat exchanger, a flow path switching valve, and an accumulator, and a plurality of indoor units including an indoor heat exchanger with a refrigerant pipe. Shaped air conditioners are known. As an example of this type of multi-room air conditioner, there is a multi-room air conditioner that changes the number of indoor units operated in accordance with the required capacity of the entire indoor unit that is operating (see, for example, Patent Document 1). ).

このような多室形空気調和装置では、各々の室内機の運転モードを冷房運転から暖房運転に切換えるときに室外熱交換器の機能を凝縮器から蒸発器へ変更するため、または、各々の室内機の運転モードを暖房運転から冷房運転に切換えるときに室外熱交換器の機能を蒸発器から凝縮器へ変更するため、室外機の流路切換弁により冷媒の流路の方向を切換える。 In such a multi-room air conditioner, the function of the outdoor heat exchanger is changed from the condenser to the evaporator when the operation mode of each indoor unit is switched from the cooling operation to the heating operation, or each indoor unit In order to change the function of the outdoor heat exchanger from the evaporator to the condenser when the operation mode of the machine is switched from the heating operation to the cooling operation, the direction of the refrigerant flow path is switched by the flow path switching valve of the outdoor unit.

このような多室形空気調和装置において、複数の室外機のうち、一部の室外機に備えた圧縮機のみを運転している場合（例えば、運転している室内機全体の要求能力が小さく、複数の室外機のうち、１台の室外機に備えた圧縮機のみを運転している場合）における運転中の圧縮機を備えた室外機と運転中の圧縮機が存在しない室外機との間の接続状態を説明する。室内機の運転モードの切換えに伴い、運転中の圧縮機を備えた室外機における室外熱交換器の機能を凝縮器から蒸発器へ変更するために室外機の流路切換弁を切換えたときの、運転中の圧縮機を備えた室外機と運転中の圧縮機が存在しない室外機との間の接続状態は次のようになる。 In such a multi-room air conditioner, when only the compressors provided in some of the outdoor units are operating (for example, the required capacity of the entire operating indoor unit is small). In the case of operating only a compressor provided in one outdoor unit among a plurality of outdoor units), an outdoor unit having an operating compressor and an outdoor unit having no operating compressor The connection state between will be described. When the operation mode of the indoor unit is switched, when the outdoor unit's flow path switching valve is switched to change the function of the outdoor heat exchanger in the outdoor unit equipped with the operating compressor from the condenser to the evaporator. The connection state between the outdoor unit equipped with the operating compressor and the outdoor unit without the operating compressor is as follows.

運転中の圧縮機を備えた室外機の流路切換弁を切換えたとき、運転中の圧縮機が存在しない室外機の流路切換弁も同時に切換えられるため、運転中の圧縮機が存在しない室外機の室外熱交換器が、流路切換弁、冷媒配管を通じて運転中の圧縮機を備えた室外機のアキュムレータに連通する。このため、このアキュムレータに連通する圧縮機の冷媒吸入により、運転中の圧縮機が存在しない室外機の室外熱交換器にとどまっている冷媒が、運転中の圧縮機を備えた室外機の室外熱交換器にとどまっている冷媒とともに、運転中の圧縮機を備えた室外機のアキュムレータに流入する。このような運転中の圧縮機を備えた室外機のアキュムレータに冷媒が流入する現象が、室外機の流路切換弁の切換によって室外熱交換器の機能を凝縮器から蒸発器へ変更する毎に、同じ室外機で繰り返されると、同じアキュムレータに冷媒が集中してオーバーフローを起こすおそれがある。運転中の圧縮機を備えた室外機のアキュムレータがオーバーフローを起こすと、このアキュムレータに連通する圧縮機に液バックが発生するおそれがあった。なお、上述した運転中の圧縮機を備えた室外機の室外熱交換器にとどまっている冷媒とは、この室外熱交換器の機能を凝縮器から蒸発器として機能させるように変更したときに蒸発しきれずにとどまっている冷媒（以下の説明では、室外熱交換器にとどまっている冷媒と表記する。）を示す。また、上述した運転中の圧縮機が存在しない室外機の室外熱交換器にとどまっている冷媒とは、この室外熱交換器を凝縮器として機能させているときに圧縮機を停止した場合にとどまっている冷媒（以下の説明では、室外熱交換器にとどまっている冷媒と表記する。）を示す。 When the flow path switching valve of an outdoor unit equipped with an operating compressor is switched, the flow path switching valve of an outdoor unit that does not have an operating compressor is also switched at the same time. The outdoor heat exchanger of the machine communicates with the accumulator of the outdoor unit provided with the operating compressor through the flow path switching valve and the refrigerant pipe. For this reason, the refrigerant remaining in the outdoor heat exchanger of the outdoor unit in which there is no compressor in operation due to refrigerant suction of the compressor communicating with this accumulator is the outdoor heat of the outdoor unit equipped with the compressor in operation. Together with the refrigerant remaining in the exchanger, it flows into the accumulator of the outdoor unit equipped with the operating compressor. The phenomenon that the refrigerant flows into the accumulator of the outdoor unit equipped with the compressor in operation is changed every time the function of the outdoor heat exchanger is changed from the condenser to the evaporator by switching the flow path switching valve of the outdoor unit. If repeated in the same outdoor unit, the refrigerant may concentrate on the same accumulator and overflow. When an accumulator of an outdoor unit equipped with an operating compressor overflows, there is a possibility that a liquid back may occur in the compressor communicating with the accumulator. Note that the refrigerant remaining in the outdoor heat exchanger of the outdoor unit including the operating compressor described above is evaporated when the function of the outdoor heat exchanger is changed from a condenser to function as an evaporator. Refrigerant remaining without being exhausted (in the following description, referred to as refrigerant remaining in the outdoor heat exchanger). In addition, the refrigerant that remains in the outdoor heat exchanger of the outdoor unit in which the compressor in operation does not exist is only when the compressor is stopped when the outdoor heat exchanger functions as a condenser. (In the following description, it is expressed as a refrigerant remaining in the outdoor heat exchanger).

特開平２−１２６０５５号公報Japanese Patent Laid-Open No. 2-126055

本発明は上記問題点に鑑み、複数の室外機のうち、一部の室外機に備えた圧縮機のみを運転中、室外熱交換器の機能を凝縮器から蒸発器へ変更したとき、運転中の圧縮機を備えた室外機におけるアキュムレータのオーバーフローを防止することができる多室形空気調和装置を提供することを目的とする。 In view of the above problems, the present invention is in operation when only the compressors included in some of the outdoor units are operating, and the function of the outdoor heat exchanger is changed from the condenser to the evaporator. An object of the present invention is to provide a multi-room air conditioner that can prevent overflow of an accumulator in an outdoor unit equipped with the above compressor.

上記課題を解決するため、本発明の多室形空気調和装置は、圧縮機と室外熱交換器と流路切換弁とアキュムレータとを備える複数の室外機と、室内熱交換器を備える複数の室内機とを設け、複数の室外機と複数の室内機とを冷媒配管で接続して構成されている。この多室形空気調和装置は、複数の室外機のうち、運転中の圧縮機が存在しない室外機が存在するとき、室外機の流路切換弁の切換によって、室外熱交換器の機能を凝縮器から蒸発器へと変更した場合に、運転する圧縮機を前記運転中の圧縮機が存在しない室外機に備えられた圧縮機に変更する。 In order to solve the above problems, a multi-room air conditioner of the present invention includes a plurality of outdoor units including a compressor, an outdoor heat exchanger, a flow path switching valve, and an accumulator, and a plurality of indoor units including an indoor heat exchanger. And a plurality of outdoor units and a plurality of indoor units are connected by refrigerant piping. This multi-room air conditioner condenses the function of the outdoor heat exchanger by switching the flow path switching valve of the outdoor unit when there is an outdoor unit that does not have an operating compressor among a plurality of outdoor units. When changing from an evaporator to an evaporator, the compressor to be operated is changed to a compressor provided in an outdoor unit where there is no compressor in operation.

本発明の多室形空気調和装置によれば、複数の室外機のうち、運転中の圧縮機が存在しない室外機が存在するとき、室外機の流路切換弁の切換によって、室外熱交換器の機能を凝縮器から蒸発器へと変更した場合に、運転する圧縮機を前記運転中の圧縮機が存在しない室外機に備えられた圧縮機に変更することで、各室外機のアキュムレータに冷媒を分散させることができる。この結果、運転中の圧縮機が存在しない室外機の室外熱交換器および運転中の圧縮機を備えた室外機の室外熱交換器にとどまっている冷媒が、運転中の圧縮機を備えた室外機のアキュムレータへ集中するのを抑えることができる。これにより、運転中の圧縮機を備えた室外機におけるアキュムレータのオーバーフローを防止することができる。 According to the multi-room air conditioner of the present invention, when there is an outdoor unit that does not have an operating compressor among the plurality of outdoor units, the outdoor heat exchanger is switched by switching the flow path switching valve of the outdoor unit. When the function of the condenser is changed from the condenser to the evaporator, the refrigerant to be operated is changed to the compressor provided in the outdoor unit in which the operating compressor does not exist, so that the refrigerant is stored in the accumulator of each outdoor unit. Can be dispersed. As a result, the refrigerant remaining in the outdoor heat exchanger of the outdoor unit having no compressor in operation and the outdoor heat exchanger of the outdoor unit having the compressor in operation is separated from the outdoor unit having the compressor in operation. Concentration on the machine accumulator can be suppressed. Thereby, the overflow of the accumulator in the outdoor unit provided with the compressor in operation can be prevented.

本発明による多室形空気調和装置の冷媒回路を示す説明図である。It is explanatory drawing which shows the refrigerant circuit of the multi-chamber type air conditioning apparatus by this invention. 本発明による室外機の運転制御を示すタイミングチャートである。It is a timing chart which shows the operation control of the outdoor unit by this invention. 本発明による室外機の運転制御を示すフローチャートである。It is a flowchart which shows the operation control of the outdoor unit by this invention.

以下、本発明の実施形態を添付図面に基づき詳細に説明する。本発明の実施形態として、３台の室外機と５台の室内機とが冷媒配管で接続され、室内機毎に冷房運転と暖房運転とを選択して運転できる、所謂冷暖房フリーの運転が行える多室形空気調和装置を例に挙げて説明する。 Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. As an embodiment of the present invention, three outdoor units and five indoor units are connected by a refrigerant pipe, and a so-called cooling / heating-free operation can be performed in which a cooling operation and a heating operation can be selected for each indoor unit. A multi-chamber air conditioner will be described as an example.

図１に示すように、本実施形態における多室形空気調和装置１は、３台の室外機２ａ〜２ｃと、５台の室内機８ａ〜８ｅと、５台の分流ユニット６ａ〜６ｅと、高圧ガス管３０と、低圧ガス管３１と、液管３２と、高圧ガス分岐器７０と、低圧ガス分岐器７１と、液分岐器７３とを備えている。室外機２ａ〜２ｃがそれぞれ、高圧ガス分岐器７０および高圧ガス管３０と、低圧ガス分岐器７１および低圧ガス管３１とによって分流ユニット６ａ〜６ｅに接続され、液分岐器７２および液管３２によって室内機８ａ〜８ｅに接続されることで、多室形空気調和装置１の冷媒回路が構成される。 As shown in FIG. 1, the multi-room air conditioner 1 in the present embodiment includes three outdoor units 2a to 2c, five indoor units 8a to 8e, and five shunt units 6a to 6e. A high-pressure gas pipe 30, a low-pressure gas pipe 31, a liquid pipe 32, a high-pressure gas branching device 70, a low-pressure gas branching device 71, and a liquid branching device 73 are provided. The outdoor units 2a to 2c are connected to the flow dividing units 6a to 6e by the high pressure gas branch 70 and the high pressure gas pipe 30, and the low pressure gas branch 71 and the low pressure gas pipe 31, respectively. The refrigerant circuit of the multi-room air conditioner 1 is configured by being connected to the indoor units 8a to 8e.

この多室形空気調和装置１では、室外機２ａ〜２ｃや分流ユニット６ａ〜６ｅに備えられた各種弁類の開閉状態に応じて、様々な運転動作が可能である。図１では、多室形空気調和装置１の冷媒回路について、これら運転動作の中から、全ての室内機８ａ〜８ｅで冷房運転を行っている場合を代表例に挙げて説明する。 In this multi-room air conditioner 1, various operation operations are possible depending on the open / close states of various valves provided in the outdoor units 2a to 2c and the diversion units 6a to 6e. In FIG. 1, the refrigerant circuit of the multi-room air conditioner 1 will be described by taking as a representative example the case where the cooling operation is performed in all the indoor units 8a to 8e from among these operation operations.

図１に示すように、３台の室外機２ａ〜２ｃはそれぞれ、主として、圧縮機２１ａ〜２１ｃと、四方弁２２ａ〜２２ｃと、室外熱交換器２３ａ〜２３ｃと、アキュムレータ２４ａ〜２４ｃと、室外ファン２６ａ〜２６ｃと、室外膨張弁２７ａ〜２７ｃと、閉鎖弁４０ａ〜４０ｃ、閉鎖弁４１ａ〜４１ｃおよび閉鎖弁４２ａ〜４２ｃとを備えている。なお、室外機２ａ〜２ｃの構成は全て同じであるため、室外機２ａのみの構成について説明を行い、その他の室外機２ｂ、２ｃの構成については説明を省略する。 As shown in FIG. 1, each of the three outdoor units 2a to 2c mainly includes compressors 21a to 21c, four-way valves 22a to 22c, outdoor heat exchangers 23a to 23c, accumulators 24a to 24c, and outdoor units. Fans 26a to 26c, outdoor expansion valves 27a to 27c, closing valves 40a to 40c, closing valves 41a to 41c, and closing valves 42a to 42c are provided. Since the configurations of the outdoor units 2a to 2c are all the same, only the configuration of the outdoor unit 2a will be described, and the description of the configuration of the other outdoor units 2b and 2c will be omitted.

圧縮機２１ａは、インバータ回路により回転数が制御される図示しないモータによって駆動され運転容量を可変できる能力可変型圧縮機である。図１に示すように、圧縮機２１ａの冷媒吐出口は、室外機高圧ガス管３３ａで閉鎖弁４０ａに接続されており、室外機高圧ガス管３３ａから接続点Ｐで分岐した冷媒配管が四方弁２２ａに接続されている。また、圧縮機２１ａの冷媒吸入口は、冷媒配管でアキュムレータ２４ａの流出側に接続されている。 The compressor 21a is a variable capacity compressor that is driven by a motor (not shown) whose rotational speed is controlled by an inverter circuit and can vary the operation capacity. As shown in FIG. 1, the refrigerant discharge port of the compressor 21a is connected to the closing valve 40a by an outdoor unit high-pressure gas pipe 33a, and the refrigerant pipe branched from the outdoor unit high-pressure gas pipe 33a at a connection point P is a four-way valve. 22a. The refrigerant inlet of the compressor 21a is connected to the outflow side of the accumulator 24a through a refrigerant pipe.

四方弁２２ａは、冷媒の流れる方向を切換えるための流路切換弁であり、４つのポートａ〜ｄを備えている。四方弁２２ａでは、ポートａに室外機高圧ガス管３３ａから接続点Ｐで分岐した冷媒配管が接続されている。また、四方弁２２ａでは、ポートｂに冷媒配管である接続管３６ａが接続され、ポートｃに冷媒配管である接続管３７ａが接続されている。なお、ポートｄは封止されている。 The four-way valve 22a is a flow path switching valve for switching the direction in which the refrigerant flows, and includes four ports a to d. In the four-way valve 22a, a refrigerant pipe branched from the outdoor unit high-pressure gas pipe 33a at the connection point P is connected to the port a. In the four-way valve 22a, a connection pipe 36a that is a refrigerant pipe is connected to the port b, and a connection pipe 37a that is a refrigerant pipe is connected to the port c. The port d is sealed.

室外熱交換器２３ａは、アルミ材で形成された多数のフィンと、内部に冷媒を流通させる複数の銅管とから構成されている。室外熱交換器２３ａの一端は接続管３６ａを介して四方弁２２ａのポートｂに、室外熱交換器２３ａの他端は室外機液管３５ａを介して閉鎖弁４２ａに、それぞれ接続されている。 The outdoor heat exchanger 23a is composed of a large number of fins formed of an aluminum material and a plurality of copper tubes through which a refrigerant flows. One end of the outdoor heat exchanger 23a is connected to the port b of the four-way valve 22a via the connecting pipe 36a, and the other end of the outdoor heat exchanger 23a is connected to the closing valve 42a via the outdoor unit liquid pipe 35a.

アキュムレータ２４ａは、流入した冷媒をガス冷媒と液冷媒とに分離し、ガス冷媒のみを圧縮機２１ａに吸入させる。上述したように、アキュムレータ２４ａの流出側は圧縮機２１ａの冷媒吸入口に冷媒配管で接続されており、アキュムレータ２４ａの流入側は四方弁２２ａのポートｃに、接続管３７ａで接続されている。なお、接続管３７ａには接続点Ｑで室外機低圧ガス管３４ａが接続されている。 The accumulator 24a separates the inflowing refrigerant into a gas refrigerant and a liquid refrigerant, and causes only the gas refrigerant to be sucked into the compressor 21a. As described above, the outflow side of the accumulator 24a is connected to the refrigerant suction port of the compressor 21a through the refrigerant pipe, and the inflow side of the accumulator 24a is connected to the port c of the four-way valve 22a through the connection pipe 37a. The outdoor unit low-pressure gas pipe 34a is connected to the connection pipe 37a at the connection point Q.

室外ファン２６ａは、図示しないファンモータによって回転することで室外機２ａの内部に外気を取り込み、室外熱交換器２３ａにおいて外気と冷媒とを熱交換させた後、室外機２ａの外部へ排出する。 The outdoor fan 26a is rotated by a fan motor (not shown) to take outside air into the outdoor unit 2a, exchange heat between the outdoor air and the refrigerant in the outdoor heat exchanger 23a, and then discharge the outside air to the outside of the outdoor unit 2a.

室外膨張弁２７ａは、室外機液管３５ａの室外熱交換器２３ａと閉鎖弁４２ａとの間に介設されている。室外膨張弁２７ａは、室外熱交換器２３ａが凝縮器として機能する場合は、その開度が全開状態とされるか、後述する高圧センサ５０ａで検出された冷媒圧力と中間圧センサ５２ａで検出された液圧との差に応じて調整される。また、室外熱交換器２３ａが蒸発器として機能する場合は、その開度が室外熱交換器２３ａにおける冷媒の過熱度（後述する低圧センサ５１ａで検出した圧縮機２１ａの吸入圧力から算出した低圧飽和温度と、熱交温度センサ５６ａで検出した冷媒出口温度との差）に応じて調整される。 The outdoor expansion valve 27a is interposed between the outdoor heat exchanger 23a and the closing valve 42a of the outdoor unit liquid pipe 35a. When the outdoor heat exchanger 23a functions as a condenser, the outdoor expansion valve 27a is fully opened or is detected by a refrigerant pressure detected by a high pressure sensor 50a described later and an intermediate pressure sensor 52a. It is adjusted according to the difference with the hydraulic pressure. When the outdoor heat exchanger 23a functions as an evaporator, the degree of opening of the outdoor heat exchanger 23a is the degree of superheat of the refrigerant in the outdoor heat exchanger 23a (low-pressure saturation calculated from the suction pressure of the compressor 21a detected by a low-pressure sensor 51a described later) The temperature is adjusted according to the difference between the temperature and the refrigerant outlet temperature detected by the heat exchanger temperature sensor 56a.

室外機２ａには各種のセンサが設けられている。図１に示すように、室外機高圧ガス管３３ａには、室外機高圧ガス管３３ａを流れる冷媒の圧力を検出する高圧センサ５０ａと、圧縮機２１ａから吐出される冷媒の温度を検出する吐出温度センサ５３ａとが設けられている。接続点Ｑと閉鎖弁４１ａとの間の室外機低圧ガス管３４ａには、圧縮機２１ａに吸入される冷媒の圧力を検出する低圧センサ５１ａが設けられ、圧縮機２１ａの冷媒吸入口とアキュムレータ２４ａの流出側とを接続する冷媒配管には、圧縮機２１ａに吸入される冷媒の温度を検出する吸入温度センサ５４aが設けられている。室外膨張弁２７ａと閉鎖弁４２ａとの間の室外機液管３５ａには、室外機液管３５ａを流れる冷媒の圧力を検出する中間圧センサ５２ａと、室外機液管３５ａを流れる冷媒の温度を検出する冷媒温度センサ５５ａとが設けられている。 Various sensors are provided in the outdoor unit 2a. As shown in FIG. 1, the outdoor unit high pressure gas pipe 33a includes a high pressure sensor 50a for detecting the pressure of the refrigerant flowing through the outdoor unit high pressure gas pipe 33a, and a discharge temperature for detecting the temperature of the refrigerant discharged from the compressor 21a. A sensor 53a is provided. The outdoor unit low-pressure gas pipe 34a between the connection point Q and the closing valve 41a is provided with a low-pressure sensor 51a for detecting the pressure of the refrigerant sucked into the compressor 21a. The refrigerant suction port of the compressor 21a and the accumulator 24a An intake temperature sensor 54a for detecting the temperature of the refrigerant sucked into the compressor 21a is provided in the refrigerant pipe connecting the outlet side of the refrigerant. The outdoor unit liquid pipe 35a between the outdoor expansion valve 27a and the closing valve 42a includes an intermediate pressure sensor 52a for detecting the pressure of the refrigerant flowing through the outdoor unit liquid pipe 35a, and the temperature of the refrigerant flowing through the outdoor unit liquid pipe 35a. A refrigerant temperature sensor 55a for detection is provided.

接続管３６ａには、室外熱交換器２３ａから流出あるいは室外熱交換器２３ａへ流入する冷媒の温度を検出する熱交温度センサ５６ａが設けられている。また、室外機２ａの図示しない吸込口付近には、室外機２ａ内に流入する外気の温度を検出する外気温度センサ５７ａが備えられている。 The connection pipe 36a is provided with a heat exchange temperature sensor 56a that detects the temperature of the refrigerant flowing out of the outdoor heat exchanger 23a or flowing into the outdoor heat exchanger 23a. Further, an outdoor temperature sensor 57a for detecting the temperature of the outside air flowing into the outdoor unit 2a is provided in the vicinity of a suction port (not shown) of the outdoor unit 2a.

なお、室外機２ｂ、２ｃについては、上述の各構成の記号末尾をそれぞれａからｂあるいはｃに変更したものを図１に示している。但し、各四方弁２２ｂ、２２ｃのポートおよび冷媒配管の接続点については記号を変えており、四方弁２２ａのポートａ〜ｄに対応して、四方弁２２ｂではポートｅ〜ｈ、四方弁２２ｃではポートｊ〜ｎとしている。また、接続点Ｐ、Ｑに対応して、室外機２ｂでは接続点Ｓ、Ｔ、室外機２ｃでは接続点Ｖ、Ｗとしている。 In addition, about outdoor unit 2b, 2c, what changed the symbol end of the above-mentioned each structure from a to b or c is shown in FIG. However, the symbols of the ports of the four-way valves 22b and 22c and the connection points of the refrigerant pipes are changed. Corresponding to the ports a to d of the four-way valve 22a, the ports e to h in the four-way valve 22b and the ports in the four-way valve 22c Ports j to n are set. Corresponding to the connection points P and Q, connection points S and T are used in the outdoor unit 2b, and connection points V and W are used in the outdoor unit 2c.

図１に示すように、多室形空気調和装置１が冷房運転を行っている際の冷媒回路では、各々の室外機２ａ〜２ｃに備えられた室外熱交換器２３ａ〜２３ｃがそれぞれ凝縮器として機能するように、各々の四方弁２２ａ〜２２ｃが切換えられる。四方弁２２ａではポートａとポートｂおよびポートｃとポートｄとが各々連通するように、四方弁２２ｂではポートｅとポートｆおよびポートｇとポートｈとが各々連通するように、四方弁２２ｃではポートｊとポートｋおよびポートｍとポートｎとが各々連通するようにそれぞれ切換えられる。図１では、四方弁２２ａ〜２２ｃの連通しているポート間は実線で示し、連通していないポート間は破線で示している。多室形空気調和装置１が冷房主体運転を行っている際の冷媒回路についても同様に、各々の室外機２ａ〜２ｃに備えられた室外熱交換器２３ａ〜２３ｃがそれぞれ凝縮器として機能するように、各々の四方弁２２ａ〜２２ｃが切換えられる。なお、冷房主体運転とは、冷房運転を行っている室内機全体の要求能力が暖房運転を行っている室内機全体の要求能力よりも大きくなる運転である。 As shown in FIG. 1, in the refrigerant circuit when the multi-room air conditioner 1 is performing a cooling operation, the outdoor heat exchangers 23a to 23c provided in the outdoor units 2a to 2c are respectively condensers. Each four-way valve 22a-22c is switched to function. In the four-way valve 22a, the port a and the port b and the port c and the port d communicate with each other. In the four-way valve 22b, the port e and the port f and the port g and port h communicate with each other. The ports j and k and the ports m and n are switched so as to communicate with each other. In FIG. 1, the ports that communicate with the four-way valves 22a to 22c are indicated by solid lines, and the ports that are not communicated are indicated by broken lines. Similarly, the outdoor heat exchangers 23a to 23c provided in the outdoor units 2a to 2c also function as condensers in the refrigerant circuit when the multi-room air conditioner 1 is performing the cooling main operation. In addition, each of the four-way valves 22a to 22c is switched. The cooling main operation is an operation in which the required capacity of the entire indoor unit performing the cooling operation is larger than the required capacity of the entire indoor unit performing the heating operation.

なお、多室形空気調和装置１が暖房運転を行っている際の冷媒回路（図示を省略）では、各々の室外機２ａ〜２ｃに備えられた室外熱交換器２３ａ〜２３ｃがそれぞれ蒸発器として機能するように、各々の四方弁２２ａ〜２２ｃが切換えられる。四方弁２２ａではポートａとポートｄおよびポートｂとポートｃとが各々連通するように、四方弁２２ｂではポートｅとポートｈおよびポートｆとポートｇとが各々連通するように、四方弁２２ｃではポートｊとポートｎおよびポートｋとポートｍとが各々連通するようにそれぞれ切換えられる。また、多室形空気調和装置１が暖房主体運転を行っている際の冷媒回路についても同様に、各々の室外機２ａ〜２ｃに備えられた室外熱交換器２３ａ〜２３ｃがそれぞれ蒸発器として機能するように、各々の四方弁２２ａ〜２２ｃが切換えられる。なお、暖房主体運転とは、暖房運転を行っている室内機全体の要求能力が冷房運転を行っている室内機全体の要求能力よりも大きくなる運転である。 In the refrigerant circuit (not shown) when the multi-room air conditioner 1 is performing the heating operation, the outdoor heat exchangers 23a to 23c provided in the outdoor units 2a to 2c are respectively used as evaporators. Each four-way valve 22a-22c is switched to function. In the four-way valve 22a, the port a and the port d and the port b and the port c communicate with each other. In the four-way valve 22b, the port e and the port h and the port f and the port g communicate with each other. The ports j and n and the ports k and m are switched so as to communicate with each other. Similarly, the outdoor heat exchangers 23a to 23c provided in the outdoor units 2a to 2c function as evaporators in the refrigerant circuit when the multi-room air conditioner 1 performs the heating-main operation. Thus, each of the four-way valves 22a to 22c is switched. The heating main operation is an operation in which the required capacity of the entire indoor unit performing the heating operation is greater than the required capacity of the entire indoor unit performing the cooling operation.

以上説明してきた構成の他に、図示を省略するが、室外機２ａには、室外機２ａを構成する各部の動作を制御する室外機制御部が備えられている。この室外機制御部は、室外機２ａの制御を行うために設けられたマイクロコンピュータや記憶部、圧縮機２１ａに搭載されたモータを制御するインバータ回路などを有しており、各種センサで検出した情報に応じて室外機２ａを制御し、また、５台の室内機８ａ〜８ｅとの間で運転に必要な制御信号のやりとりを行っている。なお、室外機２ｂおよび２ｃにも、同様の室外機制御部を備えている。 In addition to the configuration described above, although not shown, the outdoor unit 2a is provided with an outdoor unit control unit that controls the operation of each unit constituting the outdoor unit 2a. This outdoor unit control unit has a microcomputer and a storage unit provided to control the outdoor unit 2a, an inverter circuit that controls a motor mounted on the compressor 21a, and the like, which are detected by various sensors. The outdoor unit 2a is controlled according to the information, and control signals necessary for operation are exchanged with the five indoor units 8a to 8e. The outdoor units 2b and 2c are also provided with a similar outdoor unit control unit.

また、室外機２ａを親機、室外機２ｂおよび２ｃを子機とし、室外機２ａの室外機制御部が、室内機８ａ〜８ｅの全体の要求能力に応じて、室外機２ａ〜２ｃの運転／停止や、室外機２ａ〜２ｃに備えた圧縮機の運転台数を決定している。その上で、室外機２ａの室外機制御部は、その他の室外機２ｂおよび２ｃの室外機制御部に対して、室外機２ｂおよび２ｃの運転／停止や、決定した運転台数で圧縮機を運転するように指示を行っている。室外機２ａの室外機制御部は、例えば、室内機８ａ〜８ｅの全体の要求能力が小さく、１台の圧縮機のみの運転でよい場合には、室外機２ａ〜２ｃのいずれかに備える圧縮機を運転するように制御する。 The outdoor unit 2a is a master unit, the outdoor units 2b and 2c are slave units, and the outdoor unit control unit of the outdoor unit 2a operates the outdoor units 2a to 2c according to the overall required capacity of the indoor units 8a to 8e. / Stop and the number of operating compressors provided in the outdoor units 2a to 2c are determined. In addition, the outdoor unit controller of the outdoor unit 2a operates / stops the outdoor units 2b and 2c and operates the compressor with the determined number of units of operation relative to the outdoor unit controllers of the other outdoor units 2b and 2c. I have instructed you to. The outdoor unit control unit of the outdoor unit 2a is provided with any one of the outdoor units 2a to 2c when the required capacity of the indoor units 8a to 8e is small and only one compressor is required to operate. Control the machine to operate.

５台の室内機８ａ〜８ｅはそれぞれ、室内熱交換器８１ａ〜８１ｅと、室内膨張弁８２ａ〜８２ｅと、室内ファン８３ａ〜８３ｅとを備えている。なお、室内機８ａ〜８ｅの構成は全て同じであるため、室内機８ａのみの構成について説明を行い、その他の室内機８ｂ〜８ｅの構成については説明を省略する。 Each of the five indoor units 8a to 8e includes indoor heat exchangers 81a to 81e, indoor expansion valves 82a to 82e, and indoor fans 83a to 83e. In addition, since all the configurations of the indoor units 8a to 8e are the same, only the configuration of the indoor unit 8a will be described, and the description of the configurations of the other indoor units 8b to 8e will be omitted.

室内熱交換器８１ａは、アルミ材で形成された多数のフィンと、内部に冷媒を流通させる複数の銅管とから構成されている。室内熱交換器８１ａの一端が室内膨張弁８２ａを介して液管３２に、室内熱交換器８１ａの他端が後述する分流ユニット６ａに、それぞれ接続されている。室内熱交換器８１ａは、室内機８ａが冷房運転を行う場合は蒸発器として機能し、室内機８ａが暖房運転を行う場合は凝縮器として機能する。 The indoor heat exchanger 81a is composed of a large number of fins formed of an aluminum material and a plurality of copper tubes through which a refrigerant flows. One end of the indoor heat exchanger 81a is connected to the liquid pipe 32 via the indoor expansion valve 82a, and the other end of the indoor heat exchanger 81a is connected to a diversion unit 6a described later. The indoor heat exchanger 81a functions as an evaporator when the indoor unit 8a performs a cooling operation, and functions as a condenser when the indoor unit 8a performs a heating operation.

室内膨張弁８２ａは、一端が室内熱交換器８１ａに接続され、他端が液管３２に接続されている。室内膨張弁８２ａは、室内熱交換器８１ａが蒸発器として機能する場合は、後述する冷媒温度センサ８４ａで検出された冷媒の温度と、後述する冷媒温度センサ８５ａで検出された冷媒の温度との差が、所定の温度差になるように開度が調整される。また、室内膨張弁８２ａは、室内熱交換器８１ａが凝縮器として機能する場合は、後述する冷媒温度センサ８５ａで検出された冷媒の温度と、高圧センサ５０ａで検出された冷媒圧力から算出した高圧飽和温度との差が、所定の温度差になるように開度が調整される。 The indoor expansion valve 82 a has one end connected to the indoor heat exchanger 81 a and the other end connected to the liquid pipe 32. When the indoor heat exchanger 81a functions as an evaporator, the indoor expansion valve 82a has a refrigerant temperature detected by a refrigerant temperature sensor 84a described later and a refrigerant temperature detected by a refrigerant temperature sensor 85a described later. The opening degree is adjusted so that the difference becomes a predetermined temperature difference. Further, when the indoor heat exchanger 81a functions as a condenser, the indoor expansion valve 82a has a high pressure calculated from the refrigerant temperature detected by the refrigerant temperature sensor 85a described later and the refrigerant pressure detected by the high pressure sensor 50a. The opening degree is adjusted so that the difference from the saturation temperature becomes a predetermined temperature difference.

室内ファン８３ａは、図示しないファンモータによって回転することで、室内機８ａの内部に室内空気を取り込み、室内熱交換器８１ａにおいて冷媒と室内空気とを熱交換させた後、室内へ供給する。 The indoor fan 83a is rotated by a fan motor (not shown), thereby taking in indoor air into the indoor unit 8a, exchanging heat between the refrigerant and the indoor air in the indoor heat exchanger 81a, and supplying the indoor air to the room.

室内機８ａには各種のセンサが設けられている。室内熱交換器８１ａの室内膨張弁８２ａ側の冷媒配管には冷媒の温度を検出する冷媒温度センサ８４ａが、また、室内熱交換器８１ａの分流ユニット６ａ側の冷媒配管には冷媒の温度を検出する冷媒温度センサ８５ａが、それぞれ設けられている。また、室内機８ａの図示しない室内空気の吸込口付近には、室内機８ａ内に流入する室内空気の温度を検出する室温センサ８６ａが設けられている。 Various sensors are provided in the indoor unit 8a. A refrigerant temperature sensor 84a for detecting refrigerant temperature is detected in the refrigerant pipe on the indoor expansion valve 82a side of the indoor heat exchanger 81a, and a refrigerant temperature is detected in the refrigerant pipe on the diversion unit 6a side of the indoor heat exchanger 81a. Refrigerant temperature sensors 85a are provided. A room temperature sensor 86a for detecting the temperature of the indoor air flowing into the indoor unit 8a is provided in the vicinity of the indoor air inlet (not shown) of the indoor unit 8a.

以上説明してきた構成の他に、図示を省略するが、室内機８ａには、室内機８ａを構成する各部の動作を制御する室内機制御部が備えられている。この室内機制御部は、室内機８ａの制御を行うために設けられたマイクロコンピュータや記憶部などを有している。室内機制御部は、図示しないリモートコントローラから送信された制御情報や、各種センサで検出した情報に応じて、室内機８ａと室内機８ａに対応する分流ユニット６ａとを制御し、また、室外機２ａ〜２ｃとの間で運転に必要な制御信号のやりとりを行っている。なお、室内機８ｂ〜８ｅにも、同様の室内機制御部を備えている。 In addition to the configuration described above, although not shown, the indoor unit 8a includes an indoor unit control unit that controls the operation of each unit constituting the indoor unit 8a. The indoor unit control unit includes a microcomputer and a storage unit that are provided to control the indoor unit 8a. The indoor unit control unit controls the indoor unit 8a and the diversion unit 6a corresponding to the indoor unit 8a according to control information transmitted from a remote controller (not shown) and information detected by various sensors. Control signals necessary for operation are exchanged with 2a to 2c. The indoor units 8b to 8e are also provided with a similar indoor unit control unit.

多室形空気調和装置１には、５台の室内機８ａ〜８ｅに対応する５台の分流ユニット６ａ〜６ｅが備えられている。分流ユニット６ａ〜６ｅはそれぞれ、第１電磁弁６１ａ〜６１ｅと、第２電磁弁６２ａ〜６２ｅと、第１分流管６３ａ〜６３ｅと、第２分流管６４ａ〜６４ｅとを備えている。なお、分流ユニット６ａ〜６ｅの構成は全て同じであるため、分流ユニット６ａのみの構成について説明を行い、その他の分流ユニット６ｂ〜６ｅの構成については説明を省略する。 The multi-room air conditioner 1 is provided with five branch units 6a to 6e corresponding to the five indoor units 8a to 8e. The diversion units 6a to 6e include first electromagnetic valves 61a to 61e, second electromagnetic valves 62a to 62e, first diversion pipes 63a to 63e, and second diversion pipes 64a to 64e, respectively. In addition, since all the structures of the flow dividing units 6a-6e are the same, only the structure of the flow dividing unit 6a is demonstrated and description is abbreviate | omitted about the structure of the other flow dividing units 6b-6e.

第１分流管６３ａの一端は高圧ガス管３０に接続されており、第２分流管６４ａの一端は低圧ガス管３１に接続されている。また、第１分流管６３ａの他端と第２分流管６４ａの他端とが相互に接続され、この接続部と室内熱交換器８１ａとが冷媒配管で接続されている。第１分流管６３ａには第１電磁弁６１ａが、また、第２分流管６４ａには第２電磁弁６２ａが、それぞれ設けられている。第１電磁弁６１ａおよび第２電磁弁６２ａをそれぞれ開閉することによって、分流ユニット６ａに対応する室内機８ａの室内熱交換器８１ａが第１分流管６３ａを介して高圧ガス管３０側に、または、第２分流管６４ａを介して低圧ガス管３１側に接続されるように冷媒の流路が切換えられる。 One end of the first branch pipe 63 a is connected to the high pressure gas pipe 30, and one end of the second branch pipe 64 a is connected to the low pressure gas pipe 31. Further, the other end of the first diversion pipe 63a and the other end of the second diversion pipe 64a are connected to each other, and the connection portion and the indoor heat exchanger 81a are connected by a refrigerant pipe. The first branch pipe 63a is provided with a first electromagnetic valve 61a, and the second branch pipe 64a is provided with a second electromagnetic valve 62a. By opening and closing each of the first electromagnetic valve 61a and the second electromagnetic valve 62a, the indoor heat exchanger 81a of the indoor unit 8a corresponding to the flow dividing unit 6a is moved to the high pressure gas pipe 30 side via the first flow dividing pipe 63a, or The refrigerant flow path is switched so as to be connected to the low-pressure gas pipe 31 side via the second branch pipe 64a.

次に、図１を用いて、室外機２ａ〜２ｃ、室内機８ａ〜８ｅおよび分流ユニット６ａ〜６ｅと、高圧ガス管３０、低圧ガス管３１および液管３２との接続状態について説明する。室外機２ａ〜２ｃの閉鎖弁４０ａ〜４０ｃには、高圧ガス分岐管３０ａ〜３０ｃの一端が接続され、高圧ガス分岐管３０ａ〜３０ｃの他端は高圧ガス分岐器７０に接続されている。この高圧ガス分岐器７０に高圧ガス管３０の一端が接続され、高圧ガス管３０の他端は分岐して分流ユニット６ａ〜６ｅの第１分流管６３ａ〜６３ｅに接続される。 Next, the connection state between the outdoor units 2a to 2c, the indoor units 8a to 8e, and the diversion units 6a to 6e, the high pressure gas pipe 30, the low pressure gas pipe 31, and the liquid pipe 32 will be described with reference to FIG. One end of the high-pressure gas branch pipes 30 a to 30 c is connected to the closing valves 40 a to 40 c of the outdoor units 2 a to 2 c, and the other end of the high-pressure gas branch pipes 30 a to 30 c is connected to the high-pressure gas branch device 70. One end of the high pressure gas pipe 30 is connected to the high pressure gas branching unit 70, and the other end of the high pressure gas pipe 30 is branched and connected to the first branch pipes 63a to 63e of the branch units 6a to 6e.

室外機２ａ〜２ｃの閉鎖弁４１ａ〜４１ｃには、低圧ガス分岐管３１ａ〜３１ｃの一端が接続され、低圧ガス分岐管３１ａ〜３１ｃの他端は低圧ガス分岐器７１に接続されている。この低圧ガス分岐器７１に低圧ガス管３１の一端が接続され、低圧ガス管３１の他端は分岐して分流ユニット６ａ〜６ｅの第２分流管６４ａ〜６４ｅに接続される。 One end of the low pressure gas branch pipes 31a to 31c is connected to the shutoff valves 41a to 41c of the outdoor units 2a to 2c, and the other end of the low pressure gas branch pipes 31a to 31c is connected to the low pressure gas branch device 71. One end of the low pressure gas pipe 31 is connected to the low pressure gas branch 71, and the other end of the low pressure gas pipe 31 is branched and connected to the second branch pipes 64a to 64e of the branch units 6a to 6e.

室外機２ａ〜２ｃの閉鎖弁４２ａ〜４２ｃには、液分岐管３２ａ〜３２ｃの一端が接続され、液分岐管３２ａ〜３２ｃの他端は液分岐器７２に接続されている。この液分岐器７２に液管３２の一端が接続され、液管３２の他端は分岐して、室内機８ａ〜８ｅの室内膨張弁８２ａ〜８２ｅに接続される。また、室内機８ａ〜８ｅの室内熱交換器８１ａ〜８１ｅと、室内機８ａ〜８ｅに各々対応する分流ユニット６ａ〜６ｅとが冷媒配管で接続される。以上説明した接続状態によって、多室形空気調和装置１の冷媒回路が構成される。 One ends of the liquid branch pipes 32a to 32c are connected to the shutoff valves 42a to 42c of the outdoor units 2a to 2c, and the other ends of the liquid branch pipes 32a to 32c are connected to the liquid branch device 72. One end of the liquid pipe 32 is connected to the liquid branching device 72, and the other end of the liquid pipe 32 branches to be connected to the indoor expansion valves 82a to 82e of the indoor units 8a to 8e. Moreover, the indoor heat exchangers 81a to 81e of the indoor units 8a to 8e and the diversion units 6a to 6e respectively corresponding to the indoor units 8a to 8e are connected by a refrigerant pipe. The refrigerant circuit of the multi-room air conditioner 1 is configured by the connection state described above.

次に、図１を用いて、多室形空気調和装置１の運転動作について説明する。なお、図１では、室外機２ａ〜２ｃや室内機８ａ〜８ｅに備えられた各熱交換器が凝縮器として機能する場合はハッチングを付し、蒸発器として機能する場合は白抜きで図示する。また、分流ユニット６ａ〜６ｅにおける第１電磁弁６１ａ〜６１ｅおよび第２電磁弁６２ａ〜６２ｅの開閉状態については、閉じている場合を黒塗りで、開いている場合を白抜きで図示する。また、矢印は冷媒の流れを示している。 Next, the operation of the multi-room air conditioner 1 will be described with reference to FIG. In addition, in FIG. 1, when each heat exchanger with which the outdoor units 2a-2c and the indoor units 8a-8e were equipped functions as a condenser, hatching is attached | subjected, and when functioning as an evaporator, it illustrates in white. . The open / closed states of the first electromagnetic valves 61a to 61e and the second electromagnetic valves 62a to 62e in the flow dividing units 6a to 6e are illustrated in black when they are closed, and are illustrated in white when they are open. Moreover, the arrow has shown the flow of the refrigerant | coolant.

図１に示すように、全ての室内機８ａ〜８ｅが冷房運転を行い、室内機８ａ〜８ｅの全体の要求能力が高く、全ての室外機２ａ〜２ｃが運転する場合、各々の室外機２ａ〜２ｃに備えられた室外熱交換器２３ａ〜２３ｃが凝縮器として機能するように、各々の四方弁２２ａ〜２２ｃが切り換えられる。室内機８ａ〜８ｅでは、各々に対応する分流ユニット６ａ〜６ｅの第１電磁弁６１ａ〜６１ｅが閉じられて第１分流管６３ａ〜６３ｅが遮断されるとともに、第２電磁弁６２ａ〜６２ｅを開いて第２分流管６４ａ〜６４ｅを連通させる状態とする。これにより、室内機８ａ〜８ｅの室内熱交換器８１ａ〜８１ｅは全て蒸発器として機能する。 As shown in FIG. 1, when all the indoor units 8 a to 8 e perform the cooling operation, and the overall required capacity of the indoor units 8 a to 8 e is high, and all the outdoor units 2 a to 2 c are operated, each outdoor unit 2 a Each of the four-way valves 22a to 22c is switched so that the outdoor heat exchangers 23a to 23c included in ˜2c function as a condenser. In the indoor units 8a to 8e, the first electromagnetic valves 61a to 61e of the branch units 6a to 6e corresponding to the indoor units 8a to 8e are closed, the first branch pipes 63a to 63e are shut off, and the second solenoid valves 62a to 62e are opened. Thus, the second branch pipes 64a to 64e are brought into a communication state. Thereby, all the indoor heat exchangers 81a to 81e of the indoor units 8a to 8e function as an evaporator.

室外機２ａにおいて、圧縮機２１ａから吐出された高圧の冷媒は、接続点Ｐから四方弁２２ａを経て室外熱交換器２３ａに流入し外気と熱交換を行って凝縮する。室外熱交換器２３ａで凝縮した冷媒は室外機液管３５ａに流入し、高圧センサ５０ａから取り込んだ冷媒圧力と、中間圧センサ５２ａから取り込んだ液圧との差に応じた開度とされた室外膨張弁２７ａを通過して中間圧の冷媒となり、閉鎖弁４２ａから液分岐管３２ａを流れて液分岐器７２に流入する。室外機２ｂおよび室外機２ｃから流出した中間圧の冷媒についても同様に、各々の閉鎖弁４２ｂおよび４２ｃに接続された液分岐管３２ｂおよび３２ｃを流れてそれぞれ液分岐器７２に流入する。 In the outdoor unit 2a, the high-pressure refrigerant discharged from the compressor 21a flows into the outdoor heat exchanger 23a from the connection point P via the four-way valve 22a, and is condensed by exchanging heat with the outside air. The refrigerant condensed in the outdoor heat exchanger 23a flows into the outdoor unit liquid pipe 35a, and the outdoor is set to an opening corresponding to the difference between the refrigerant pressure taken in from the high pressure sensor 50a and the liquid pressure taken in from the intermediate pressure sensor 52a. The refrigerant passes through the expansion valve 27a to become an intermediate pressure refrigerant, flows from the closing valve 42a through the liquid branch pipe 32a, and flows into the liquid branch device 72. Similarly, the intermediate-pressure refrigerant flowing out of the outdoor unit 2b and the outdoor unit 2c flows through the liquid branch pipes 32b and 32c connected to the respective shut-off valves 42b and 42c and flows into the liquid branch 72, respectively.

各室外機２ａ〜２ｃから液分岐器７２に流入した中間圧の冷媒は、液管３２に流入し分岐されて各々の室内機８ａ〜８ｅへ流入する。各室内機８ａ〜８ｅへ流入した中間圧の冷媒は、室内膨張弁８２ａ〜８２ｅで減圧された冷媒となり室内熱交換器８１ａ〜８１ｅに流入する。室内熱交換器８１ａ〜８１ｅに流入した冷媒は、室内空気と熱交換を行って蒸発し、これにより室内機８ａ〜８ｅが設置された室内の冷房が行われる。ここで、室内膨張弁８２ａ〜８２ｅは、冷媒温度センサ８４ａ〜８４ｅで検出した冷媒温度および冷媒温度センサ８５ａ〜８５ｅで検出した冷媒温度とから算出される、蒸発器である室内熱交換器８１ａ〜８１ｅでの冷媒過熱度に応じて開度が決定されている。 The intermediate-pressure refrigerant that has flowed into the liquid branching device 72 from each of the outdoor units 2a to 2c flows into the liquid pipe 32, is branched, and flows into the indoor units 8a to 8e. The intermediate-pressure refrigerant that has flowed into the indoor units 8a to 8e becomes refrigerant that has been depressurized by the indoor expansion valves 82a to 82e, and flows into the indoor heat exchangers 81a to 81e. The refrigerant that has flowed into the indoor heat exchangers 81a to 81e exchanges heat with room air and evaporates, thereby cooling the room in which the indoor units 8a to 8e are installed. Here, the indoor expansion valves 82a to 82e are indoor heat exchangers 81a to 81a which are evaporators calculated from the refrigerant temperature detected by the refrigerant temperature sensors 84a to 84e and the refrigerant temperature detected by the refrigerant temperature sensors 85a to 85e. The opening degree is determined according to the degree of refrigerant superheating at 81e.

室内熱交換器８１ａ〜８１ｅから流出した冷媒は分流ユニット６ａ〜６ｅに流入し、開となっている第２電磁弁６２ａ〜６２ｅが備えられた第２分流管６４ａ〜６４ｅを流れて低圧ガス管３１に流入する。低圧ガス管３１に流入した冷媒は、低圧ガス管３１内で合流後低圧ガス分岐器７１に流入し、低圧ガス分岐器７１から各低圧ガス分岐管３１ａ〜３１ｃに分岐して流れる。 The refrigerant that has flowed out of the indoor heat exchangers 81a to 81e flows into the flow dividing units 6a to 6e, flows through the second flow dividing pipes 64a to 64e provided with the opened second electromagnetic valves 62a to 62e, and is a low pressure gas pipe. 31 flows in. The refrigerant that has flowed into the low-pressure gas pipe 31 flows into the low-pressure gas branching device 71 after joining in the low-pressure gas pipe 31, and then branches from the low-pressure gas branching device 71 to the low-pressure gas branching tubes 31a to 31c.

低圧ガス分岐管３１ａから室外機２ａの閉鎖弁４１ａを経て室外機低圧ガス管３４ａに流入した冷媒は、アキュムレータ２４ａを介して圧縮機２１ａに吸入されて再び圧縮される。同様に、低圧ガス分岐管３１ｂおよび３１ｃから室外機２ｂおよび２ｃの閉鎖弁４１ｂおよび４１ｃを経て室外機低圧ガス管３４ｂおよび３４ｃに流入した冷媒は、アキュムレータ２４ｂおよび２４ｃを介して圧縮機２１ｂおよび２１ｃに吸入されて再び圧縮される。 The refrigerant that has flowed into the outdoor unit low-pressure gas pipe 34a from the low-pressure gas branch pipe 31a through the closing valve 41a of the outdoor unit 2a is sucked into the compressor 21a through the accumulator 24a and compressed again. Similarly, the refrigerant that has flowed from the low pressure gas branch pipes 31b and 31c into the outdoor unit low pressure gas pipes 34b and 34c through the shutoff valves 41b and 41c of the outdoor units 2b and 2c passes through the accumulators 24b and 24c and is compressed by the compressors 21b and 21c. Inhaled and compressed again.

次に、図２を用いて、本発明にかかる運転制御であって、四方弁２２ａ〜２２ｃの切換に連係して、各室外機２ａ〜２ｃに搭載された圧縮機２１ａ〜２１ｃの運転を変更する制御について説明する。本発明の圧縮機２１ａ〜２１ｃの運転を変更する制御は、複数の室外機２ａ〜２ｃに備えられた圧縮機２１ａ〜２１ｃのうち、停止している圧縮機が存在するとき、四方弁２２ａ〜２２ｃの切換によって、室外熱交換器２３ａ〜２３ｃの機能を凝縮器から蒸発器へ変更する毎に、停止していた圧縮機を備えた室外機において当該圧縮機を運転させたのち、運転していた圧縮機を備えた室外機において当該圧縮機を停止させることを特徴とする。このような本発明の圧縮機２１ａ〜２１ｃの運転を変更する制御によって、停止していた圧縮機を備える室外機の室外熱交換器にとどまっている冷媒と、運転している圧縮機を備えた室外機の室外機熱交換器にとどまっている冷媒とが、運転している圧縮機の冷媒吸入によって、運転している圧縮機に対応する室外機のアキュムレータに流入してオーバーフローするのを防止する。 Next, referring to FIG. 2, the operation control according to the present invention is performed, and the operation of the compressors 21a to 21c mounted on the outdoor units 2a to 2c is changed in conjunction with the switching of the four-way valves 22a to 22c. The control to perform will be described. The control for changing the operation of the compressors 21a to 21c according to the present invention is performed when the compressor 21a to 21c provided in the plurality of outdoor units 2a to 2c includes a stopped compressor. Each time the function of the outdoor heat exchangers 23a to 23c is changed from the condenser to the evaporator by switching the switch 22c, the compressor is operated in the outdoor unit having the stopped compressor. In an outdoor unit equipped with a compressor, the compressor is stopped. The control which changes the driving | operation of the compressors 21a-21c of this invention was equipped with the refrigerant | coolant which is staying in the outdoor heat exchanger of the outdoor unit provided with the compressor which has stopped, and the compressor which is drive | operating. Prevents the refrigerant remaining in the outdoor unit heat exchanger of the outdoor unit from flowing into the accumulator of the outdoor unit corresponding to the operating compressor and overflowing due to the refrigerant suction of the operating compressor. .

以下の説明では、室外機２ａ〜２ｃのうち、室外機２ｂおよび２ｃに備えた圧縮機２１ｂおよび２１ｃが停止し、室外機２ａに備えた圧縮機２１ａのみが運転を行っているとき、四方弁２２ａ〜２２ｃの切換に伴って圧縮機２１ａ〜２１ｃの運転を変更する制御について説明する。四方弁２２ａ〜２２ｃの切換は、一斉に切換られるものとし、室外機２ａに備えた圧縮機２１ａのみが運転を行っているときとは、室内機全体の要求能力が圧縮機１台の運転で足りる程度に小さくなっている状態のときとする。また、多室形空気調和装置１が冷房運転あるいは冷房主体運転を行っている際の冷媒回路における各々の四方弁２２ａ〜２２ｃの切換状態をＯＮとし、多室形空気調和装置１が暖房運転あるいは暖房主体運転を行っている際の冷媒回路における各々の四方弁２２ａ〜２２ｃの切換状態をＯＦＦとして説明する。四方弁２２ａ〜２２ｃの切換状態がＯＮのときとは、四方弁２２ａではポートａとポートｂおよびポートｃとポートｄとが各々連通し、四方弁２２ｂではポートｅとポートｆおよびポートｇとポートｈとが各々連通し、四方弁２２ｃではポートｊとポートｋおよびポートｍとポートｎとが各々連通する状態である。四方弁２２ａ〜２２ｃの切換状態がＯＦＦのときとは、四方弁２２ａではポートａとポートｄおよびポートｂとポートｃとが各々連通し、四方弁２２ｂではポートｅとポートｈおよびポートｆとポートｇとが各々連通し、四方弁２２ｃではポートｊとポートｎおよびポートｋとポートｍとが各々連通する状態である。なお、説明の便宜上、本実施形態では、多室形空気調和装置１の運転時、四方弁２２ａ〜２２ｃの切換によって室外熱交換器２３ａ〜２３ｃの機能を凝縮器と蒸発器として交互に変更するごとに、圧縮機２１ａ〜２１ｃのうちの１台を運転させる状態について第１運転状態から第６運転状態と称して説明する。四方弁２２ａ〜２２ｃの一斉切換により、室外熱交換器２３ａ〜２３ｃの機能の変更も、一斉に変更されるものとし、室形空気調和装置１の運転中は、第１運転状態の運転状態から始まって、第６運転状態の運転状態で終了し、以降はこれを繰り返すこととする。 In the following description, when the compressors 21b and 21c included in the outdoor units 2b and 2c are stopped and only the compressor 21a included in the outdoor unit 2a is operating among the outdoor units 2a to 2c, the four-way valve Control for changing the operation of the compressors 21a to 21c in accordance with the switching of 22a to 22c will be described. The four-way valves 22a to 22c are switched all at once. When only the compressor 21a provided in the outdoor unit 2a is operating, the required capacity of the entire indoor unit is the operation of one compressor. Suppose that it is small enough. Further, the switching state of each of the four-way valves 22a to 22c in the refrigerant circuit when the multi-room air conditioner 1 is performing the cooling operation or the cooling main operation is turned ON, and the multi-room air conditioner 1 The switching state of each of the four-way valves 22a to 22c in the refrigerant circuit during the heating main operation will be described as OFF. When the switching state of the four-way valves 22a to 22c is ON, in the four-way valve 22a, the port a and the port b and the port c and the port d communicate with each other, and in the four-way valve 22b, the port e and the port f and the port g and the port h is in communication with each other, and in the four-way valve 22c, port j and port k and port m and port n are in communication with each other. When the switching state of the four-way valves 22a to 22c is OFF, the port a and the port d and the port b and the port c communicate with each other in the four-way valve 22a, and the port e and the port h and the port f and the port are communicated with each other g communicate with each other, and in the four-way valve 22c, port j and port n and port k and port m communicate with each other. For convenience of explanation, in the present embodiment, during operation of the multi-chamber air conditioner 1, the functions of the outdoor heat exchangers 23a to 23c are alternately changed as a condenser and an evaporator by switching the four-way valves 22a to 22c. Each state where one of the compressors 21a to 21c is operated will be referred to as a first operation state to a sixth operation state. By simultaneous switching of the four-way valves 22a to 22c, the function of the outdoor heat exchangers 23a to 23c is also changed at the same time. During the operation of the room air conditioner 1, the operation state of the first operation state is changed. It starts and ends in the operating state of the sixth operating state, and thereafter this is repeated.

まず、図２に示す第１運転状態から第６運転状態について説明する。四方弁２２ａ〜２２ｃの切換状態がＯＮであって、室外機２ａに備えた圧縮機２１ａを運転し、室外機２ｂおよび２ｃに備えた圧縮機２１ｂおよび２１ｃを停止する状態を第１運転状態とする。四方弁２２ａ〜２２ｃの切換状態がＯＦＦであって、室外機２ｂに備えた圧縮機２１ｂを運転し、室外機２ａおよび２ｃに備えた圧縮機２１ａおよび２１ｃを停止する状態を第２運転状態とする。四方弁２２ａ〜２２ｃの切換状態がＯＮであって、室外機２ｂに備えた圧縮機２１ｂを運転し、室外機２ａおよび２ｃに備えた圧縮機２１ａおよび２１ｃを停止する状態を第３運転状態とする。四方弁２２ａ〜２２ｃの切換状態がＯＦＦであって、室外機２ｃに備えた圧縮機２１ｃを運転し、室外機２ａおよび２ｂに備えた圧縮機２１ａおよび２１ｂを停止する状態を第４運転状態とする。四方弁２２ａ〜２２ｃの切換状態がＯＮであって、室外機２ｃに備えた圧縮機２１ｃを運転し、室外機２ａおよび２ｂに備えた圧縮機２１ａおよび２１ｂを停止する状態を第５運転状態とする。四方弁２２ａ〜２２ｃの切換状態がＯＦＦであって、室外機２ａに備えた圧縮機２１ａを運転し、室外機２ｂおよび２ｃに備えた圧縮機２１ｂおよび２１ｃを停止する状態を第６運転状態とする。 First, the first operation state to the sixth operation state shown in FIG. 2 will be described. The state in which the switching state of the four-way valves 22a to 22c is ON, the compressor 21a provided in the outdoor unit 2a is operated, and the compressors 21b and 21c provided in the outdoor units 2b and 2c are stopped is referred to as the first operating state. To do. The state in which the switching state of the four-way valves 22a to 22c is OFF, the compressor 21b provided in the outdoor unit 2b is operated, and the compressors 21a and 21c provided in the outdoor units 2a and 2c are stopped is referred to as the second operating state. To do. The state in which the switching state of the four-way valves 22a to 22c is ON, the compressor 21b provided in the outdoor unit 2b is operated, and the compressors 21a and 21c provided in the outdoor units 2a and 2c are stopped is referred to as a third operating state. To do. The state in which the switching state of the four-way valves 22a to 22c is OFF, the compressor 21c included in the outdoor unit 2c is operated, and the compressors 21a and 21b included in the outdoor units 2a and 2b are stopped is referred to as a fourth operating state. To do. The state in which the switching state of the four-way valves 22a to 22c is ON, the compressor 21c provided in the outdoor unit 2c is operated, and the compressors 21a and 21b provided in the outdoor units 2a and 2b are stopped is referred to as a fifth operating state. To do. The state in which the switching state of the four-way valves 22a to 22c is OFF, the compressor 21a included in the outdoor unit 2a is operated, and the compressors 21b and 21c included in the outdoor units 2b and 2c are stopped is referred to as a sixth operating state. To do.

本実施形態における室外機２ａ〜２ｃに備えた圧縮機２１ａ〜２１ｃの運転動作では、四方弁２２ａ〜２２ｃの切換によって室外熱交換器の機能を凝縮器から蒸発器、あるいは、蒸発器から凝縮器へ変更するごとに、第１運転状態、第２運転状態、第３運転状態、第４運転状態、第５運転状態、第６運転状態、第１運転状態、・・・の順に運転を繰り返す。第１運転状態から第２運転状態へ、第３運転状態から第４運転状態へ、第５運転状態から第６運転状態へそれぞれ移行する場合は、冷房運転を行っている室内機全体の要求能力が暖房運転を行っている室内機全体の要求能力よりも小さくなり、四方弁２２ａ〜２２ｃの切換によって、室外熱交換器の機能を凝縮器から蒸発器へ変更するときである。また、第２運転状態から第３運転状態へ、第４運転状態から第５運転状態へ、第６運転状態から第１運転状態へそれぞれ移行する場合は、冷房運転を行っている室内機全体の要求能力が暖房運転を行っている室内機全体の要求能力よりも大きくなり、四方弁２２ａ〜２２ｃの切換によって、室外熱交換器の機能を蒸発器から凝縮器へ変更するときである。 In the operation of the compressors 21a to 21c provided in the outdoor units 2a to 2c in the present embodiment, the function of the outdoor heat exchanger is changed from the condenser to the evaporator, or from the evaporator to the condenser by switching the four-way valves 22a to 22c. Each time the operation is changed, the operation is repeated in the order of the first operation state, the second operation state, the third operation state, the fourth operation state, the fifth operation state, the sixth operation state, the first operation state,. When shifting from the first operation state to the second operation state, from the third operation state to the fourth operation state, and from the fifth operation state to the sixth operation state, the required capacity of the entire indoor unit performing the cooling operation Is smaller than the required capacity of the whole indoor unit performing the heating operation, and the function of the outdoor heat exchanger is changed from the condenser to the evaporator by switching the four-way valves 22a to 22c. In addition, when shifting from the second operation state to the third operation state, from the fourth operation state to the fifth operation state, and from the sixth operation state to the first operation state, the entire indoor unit performing the cooling operation This is a time when the required capacity becomes larger than the required capacity of the whole indoor unit performing the heating operation, and the function of the outdoor heat exchanger is changed from the evaporator to the condenser by switching the four-way valves 22a to 22c.

第１運転状態から第２運転状態へ移行する場合には、四方弁２２ａ〜２２ｃが切換えられると、室外熱交換器２３ａ〜２３ｃの機能は凝縮器から蒸発器に変更され、停止していた圧縮機２１ｂが運転されたのち、運転していた圧縮機２１ａを停止すると、室外熱交換器２３ｂに冷媒が流れて室外熱交換器２３が蒸発器として外気と冷媒との熱交換を行う。第３運転状態から第４運転状態へ移行する場合も上述と同様に、室外熱交換器２３ｃに冷媒が流れて室外熱交換器２３ｃが蒸発器として外気と冷媒との熱交換を行う。第５運転状態から第６運転状態へ移行する場合も上述と同様に、室外熱交換器２３ａに冷媒が流れて室外熱交換器２３ａが蒸発器として外気と冷媒との熱交換を行う。第２運転状態から第３運転状態へ移行する場合には、四方弁２２ａ〜２２ｃが切換えられ、それまで運転していた圧縮機２１ｂを継続して運転させるため、それまで蒸発器として機能していた室外熱交換器２３ｂが凝縮器として機能する。第４運転状態から第５運転状態へ移行する場合も上述と同様に、それまで蒸発器として機能していた室外熱交換器２３ｃが凝縮器として機能する。第６運転状態から第１運転状態へ移行する場合も上述と同様に、それまで蒸発器として機能していた室外熱交換器２３ａが凝縮器として機能する。 When shifting from the first operation state to the second operation state, when the four-way valves 22a to 22c are switched, the function of the outdoor heat exchangers 23a to 23c is changed from the condenser to the evaporator, and the compression that has been stopped is stopped. When the compressor 21a that has been operated is stopped after the machine 21b is operated, the refrigerant flows into the outdoor heat exchanger 23b, and the outdoor heat exchanger 23 serves as an evaporator to exchange heat between the outside air and the refrigerant. Also when shifting from the third operation state to the fourth operation state, similarly to the above, the refrigerant flows into the outdoor heat exchanger 23c, and the outdoor heat exchanger 23c serves as an evaporator to exchange heat between the outside air and the refrigerant. Also when shifting from the fifth operation state to the sixth operation state, similarly to the above, the refrigerant flows into the outdoor heat exchanger 23a, and the outdoor heat exchanger 23a serves as an evaporator to exchange heat between the outside air and the refrigerant. When shifting from the second operation state to the third operation state, the four-way valves 22a to 22c are switched, and the compressor 21b that has been operated so far is continuously operated. The outdoor heat exchanger 23b functions as a condenser. In the case of shifting from the fourth operation state to the fifth operation state, the outdoor heat exchanger 23c that has been functioning as an evaporator until then functions as a condenser as described above. When shifting from the sixth operation state to the first operation state, the outdoor heat exchanger 23a that has been functioning as an evaporator until then functions as a condenser, similarly to the above.

以上説明してきた第１運転状態から第６運転状態を順次繰り返す中で、四方弁２２ａ〜２２ｃの切換によって室外熱交換器の機能を凝縮器から蒸発器へ変更する毎に、室外機２ａ〜２ｃに備えた圧縮機２１ａ〜２１ｃが、圧縮機２１ａ、圧縮機２１ｂ、圧縮機２１ｃ、圧縮機２１ａ、・・・の順に１台ずつ運転される。このように、圧縮機２１ａ〜２１ｃを順番に運転させることにより、室外熱交換器２３ａ〜２３ｃにとどまっている冷媒が次のような経路で流れる。まず、圧縮機２１ａを運転し、圧縮機２１ｂおよび２１ｃを停止しているとき、四方弁２２ａ〜２２ｃの切換状態をＯＦＦとすることによって、室外熱交換器の機能を凝縮器から蒸発器へ変更した場合（第１運転状態→第２運転状態）、停止していた圧縮機２１ｂを運転させたのち、運転していた圧縮機２１ａを停止させる。この圧縮機の運転の変更により、圧縮機２１ｂの冷媒吸入によって、室外熱交換器２３ａにとどまっている冷媒は四方弁２２ａ、接続点Ｑ、低圧ガス分岐器７１を通じて、室外熱交換器２３ｂにとどまっている冷媒は四方弁２２ｂ、接続点Ｔを通じて、室外熱交換器２３ｃにとどまっている冷媒は四方弁２２ｃ、接続点Ｗ、低圧ガス分岐器７１を通じて、それぞれアキュムレータ２４ｂに向けて流れる。このように、室外熱交換器２３ａ〜２３ｃにとどまっている冷媒はアキュムレータ２４ｂに向けて流れ、運転していた圧縮機２１ａに接続されたアキュムレータ２４ａには流れない。 Each time the function of the outdoor heat exchanger is changed from the condenser to the evaporator by switching the four-way valves 22a to 22c while sequentially repeating the first operation state to the sixth operation state described above, the outdoor units 2a to 2c Are operated one by one in the order of the compressor 21a, the compressor 21b, the compressor 21c, the compressor 21a, and so on. As described above, by operating the compressors 21a to 21c in order, the refrigerant remaining in the outdoor heat exchangers 23a to 23c flows through the following path. First, when the compressor 21a is operated and the compressors 21b and 21c are stopped, the function of the outdoor heat exchanger is changed from the condenser to the evaporator by turning off the switching state of the four-way valves 22a to 22c. In the case of the operation (first operation state → second operation state), after the stopped compressor 21b is operated, the operated compressor 21a is stopped. Due to the change in the operation of the compressor, the refrigerant remaining in the outdoor heat exchanger 23a due to the refrigerant suction of the compressor 21b remains in the outdoor heat exchanger 23b through the four-way valve 22a, the connection point Q, and the low-pressure gas branch 71. The refrigerant remaining in the outdoor heat exchanger 23c flows through the four-way valve 22b and the connection point T, and the refrigerant flowing in the outdoor heat exchanger 23c flows through the four-way valve 22c, the connection point W, and the low-pressure gas branching unit 71 toward the accumulator 24b. As described above, the refrigerant remaining in the outdoor heat exchangers 23a to 23c flows toward the accumulator 24b and does not flow to the accumulator 24a connected to the compressor 21a that has been operated.

続いて、圧縮機２１ｂを運転し、圧縮機２１ａおよび２１ｃを停止しているとき、四方弁２２ａ〜２２ｃの切換状態をＯＦＦとすることによって、室外熱交換器の機能を凝縮器から蒸発器へ変更した場合（第３運転状態→第４運転状態）、停止していた圧縮機２１ｃを運転させたのち、運転していた圧縮機２１ｂを停止させる。この圧縮機の運転の変更についても上述と同様に、圧縮機２１ｃの冷媒吸入によって、室外熱交換器２３ａ〜２３ｃにとどまっている冷媒はアキュムレータ２４ｃに向けて流れ、運転していた圧縮機２１ｂに接続されたアキュムレータ２４ｂには流れない。続いて、圧縮機２１ｃを運転し、圧縮機２１ａおよび２１ｃを停止しているとき、四方弁２２ａ〜２２ｃの切換状態をＯＦＦとすることによって、室外熱交換器の機能を凝縮器から蒸発器へ変更した場合（第５運転状態→第６運転状態）、停止していた圧縮機２１ａを運転させたのち、運転していた圧縮機２１ｃを停止させる。この圧縮機の運転の変更についても上述と同様に、圧縮機２１ａの冷媒吸入によって、室外熱交換器２３ａ〜２３ｃにとどまっている冷媒はアキュムレータ２４ａに向けて流れ、運転していた圧縮機２１ｃに接続されたアキュムレータ２４ｃには流れない。このように室外熱交換器２３ａ〜２３ｃにとどまっている冷媒は、室外熱交換器の機能を凝縮器から蒸発器へ変更するごとに、運転される圧縮機に接続するアキュムレータに向けて流れる。 Subsequently, when the compressor 21b is operated and the compressors 21a and 21c are stopped, the function of the outdoor heat exchanger is changed from the condenser to the evaporator by turning off the switching state of the four-way valves 22a to 22c. When changed (from the third operation state to the fourth operation state), the compressor 21c that has been stopped is operated, and then the compressor 21b that has been operated is stopped. Regarding the change in the operation of the compressor, similarly to the above, the refrigerant remaining in the outdoor heat exchangers 23a to 23c flows toward the accumulator 24c by the refrigerant suction of the compressor 21c, and flows into the compressor 21b that has been operating. It does not flow to the connected accumulator 24b. Subsequently, when the compressor 21c is operated and the compressors 21a and 21c are stopped, the function of the outdoor heat exchanger is changed from the condenser to the evaporator by turning off the switching state of the four-way valves 22a to 22c. When changed (5th operation state-> 6th operation state), after operating the stopped compressor 21a, the operating compressor 21c is stopped. Regarding the change in the operation of the compressor, similarly to the above, the refrigerant remaining in the outdoor heat exchangers 23a to 23c flows toward the accumulator 24a by the refrigerant suction of the compressor 21a, and flows into the compressor 21c that has been operating. It does not flow to the connected accumulator 24c. Thus, whenever the function of the outdoor heat exchanger is changed from the condenser to the evaporator, the refrigerant remaining in the outdoor heat exchangers 23a to 23c flows toward the accumulator connected to the operated compressor.

以上説明してきたように、室外機２ａ〜２ｃに備えた圧縮機２１ａ〜２１ｃを予め定めた順番で運転させることにより次のような効果が得られる。本実施形態における多室形空気調和装置１においても背景技術で記載したように、四方弁２２ａ〜２２ｃの切換に伴って、停止している圧縮機を備えた室外機の室外熱交換器が、四方弁、低圧ガス分岐器７１を通じて、それまで運転していた圧縮機を備える室外機のアキュムレータに連通することになる。しかしながら、室外機２ａ〜２ｃに備える圧縮機２１ａ〜２１ｃが予め定めた順番で運転されるため、室外熱交換器２３ａ〜２３ｃにとどまっている冷媒が、それまで運転していた圧縮機を備える室外機のアキュムレータに流れず、新たに運転される圧縮機を備えた室外機のアキュムレータに流れることになり、運転される圧縮機の変更に伴って冷媒が流れこむアキュムレータが変更される。このため、各室外機２ａ〜２ｃのアキュムレータ２４ａ〜２４ｃに冷媒を分散させることができる。この結果、四方弁の切換え前に運転していた圧縮機を備えた室外機のアキュムレータへ冷媒が集中するのを抑えることができ、四方弁の切換え前に運転していた圧縮機を備えた室外機におけるアキュムレータのオーバーフローを防止することができる。また、四方弁の切換え前に運転していた圧縮機を備えた室外機におけるアキュムレータのオーバーフローを防止することで、このアキュムレータに連通する圧縮機への液バックの発生を防止することができる。なお、本実施形態では、圧縮機２１ａ〜２１ｃの運転動作として、第１運転状態、第２運転状態、第３運転状態、第４運転状態、第５運転状態、第６運転状態、第１運転状態、・・・の順に運転を繰り返すようにしたが、本発明はこれに限らず、第１運転状態、第４運転状態、第５運転状態、第２運転状態、第３運転状態、第６運転状態、第１運転状態、・・・の順に運転を繰り返すようにしてもよい。 As described above, the following effects can be obtained by operating the compressors 21a to 21c included in the outdoor units 2a to 2c in a predetermined order. As described in the background art in the multi-room air conditioner 1 according to the present embodiment, the outdoor heat exchanger of the outdoor unit including the compressor that is stopped along with the switching of the four-way valves 22a to 22c, The four-way valve and the low-pressure gas branching unit 71 communicate with an accumulator of an outdoor unit equipped with a compressor that has been operated. However, since the compressors 21a to 21c provided in the outdoor units 2a to 2c are operated in a predetermined order, the refrigerant remaining in the outdoor heat exchangers 23a to 23c is provided with the compressor that has been operated until then. It does not flow to the accumulator of the machine but flows to the accumulator of the outdoor unit equipped with the newly operated compressor, and the accumulator into which the refrigerant flows is changed in accordance with the change of the operated compressor. For this reason, a refrigerant | coolant can be disperse | distributed to the accumulators 24a-24c of each outdoor unit 2a-2c. As a result, it is possible to prevent the refrigerant from concentrating on the accumulator of the outdoor unit equipped with the compressor that was operating before the switching of the four-way valve, and the outdoor unit equipped with the compressor that was operated before the switching of the four-way valve. Accumulator overflow in the machine can be prevented. Further, by preventing overflow of the accumulator in the outdoor unit equipped with the compressor that has been operated before the switching of the four-way valve, it is possible to prevent occurrence of liquid back to the compressor communicating with the accumulator. In the present embodiment, the first operation state, the second operation state, the third operation state, the fourth operation state, the fifth operation state, the sixth operation state, and the first operation are performed as the operation operations of the compressors 21a to 21c. However, the present invention is not limited to this, but the first operation state, the fourth operation state, the fifth operation state, the second operation state, the third operation state, The operation may be repeated in the order of the operation state, the first operation state, and so on.

次に、図３のフローチャートを用いて、３台の室外機２ａ〜２ｃのうち、１台の室外機に備えた圧縮機のみを運転する多室形空気調和装置１において、親機である室外機２ａに備えた室外機制御部が、四方弁２２ａ〜２２ｃの切換によって、室外機２ａ〜２ｃの室外熱交換器２３ａ〜２３ｃの機能を凝縮器から蒸発器へ変更する場合の圧縮機２１ａ〜２１ｃの運転を変更する制御について説明する。図３において、Ｓはステップを、数字はステップ番号をそれぞれ表す。 Next, in the multi-room air conditioner 1 that operates only the compressor provided in one of the three outdoor units 2a to 2c, the outdoor unit that is the master unit is used, using the flowchart of FIG. When the outdoor unit control unit provided in the unit 2a changes the function of the outdoor heat exchangers 23a to 23c of the outdoor units 2a to 2c from the condenser to the evaporator by switching the four-way valves 22a to 22c, the compressor 21a to The control which changes the driving | operation of 21c is demonstrated. In FIG. 3, S represents a step, and a number represents a step number.

室外機２ａに備えた室外機制御部は、多室形空気調和装置１が運転を開始してから、運転している圧縮機が１台であるか否かを判断する（Ｓ１）。運転している圧縮機が１台であれば（Ｓ１−ＹＥＳ）、Ｓ２に移行し、運転している圧縮機が２台または３台であれば（Ｓ１−ＮＯ）、Ｓ８に移行する。Ｓ２では、室外機２ａに備えた室外機制御部は、四方弁の切換状態（ＯＮまたはＯＦＦ）を監視することにより室外熱交換器を蒸発器として使用しているか否かを判断する。室外熱交換器を蒸発器として使用していれば（Ｓ２−ＹＥＳ）、Ｓ３に移行し、室外熱交換器を凝縮器として使用していれば（Ｓ２−ＮＯ）、Ｓ５に移行する。 The outdoor unit controller provided in the outdoor unit 2a determines whether or not there is only one compressor operating after the multi-room air conditioner 1 starts operating (S1). If the number of operating compressors is one (S1-YES), the process proceeds to S2. If the number of operating compressors is two or three (S1-NO), the process proceeds to S8. In S2, the outdoor unit controller provided in the outdoor unit 2a determines whether or not the outdoor heat exchanger is used as an evaporator by monitoring the switching state (ON or OFF) of the four-way valve. If the outdoor heat exchanger is used as an evaporator (S2-YES), the process proceeds to S3, and if the outdoor heat exchanger is used as a condenser (S2-NO), the process proceeds to S5.

Ｓ３では、室外機２ａに備えた室外機制御部は、冷房運転を行っている室内機全体の要求能力が暖房運転を行っている室内機全体の要求能力よりも大きいか否かを判断する。冷房運転を行っている室内機全体の要求能力が暖房運転を行っている室内機全体の要求能力よりも大きければ（Ｓ３−ＹＥＳ）、Ｓ４に移行し、冷房運転を行っている室内機全体の要求能力が暖房運転を行っている室内機全体の要求能力よりも小さければ（Ｓ３−ＮＯ）、Ｓ１に戻る。Ｓ４では、室外機２ａに備えた室外機制御部は、四方弁２２ａ〜２２ｃを切換える（ＯＦＦ→ＯＮ）。Ｓ４において四方弁２２ａ〜２２ｃを切換えた後、Ｓ９に移行する。 In S3, the outdoor unit control unit provided in the outdoor unit 2a determines whether or not the required capacity of the entire indoor unit performing the cooling operation is greater than the required capacity of the entire indoor unit performing the heating operation. If the required capacity of the entire indoor unit performing the cooling operation is larger than the required capacity of the entire indoor unit performing the heating operation (S3-YES), the process proceeds to S4, and the entire indoor unit performing the cooling operation is If the required capacity is smaller than the required capacity of the whole indoor unit performing the heating operation (S3-NO), the process returns to S1. In S4, the outdoor unit controller provided in the outdoor unit 2a switches the four-way valves 22a to 22c (OFF → ON). After the four-way valves 22a to 22c are switched in S4, the process proceeds to S9.

Ｓ５では、室外機２ａに備えた室外機制御部は、暖房運転を行っている室内機全体の要求能力が冷房運転を行っている室内機全体の要求能力以上であるか否かを判断する。暖房運転を行っている室内機全体の要求能力が冷房運転を行っている室内機全体の要求能力以上であれば（Ｓ５−ＹＥＳ）、Ｓ６に移行し、暖房運転を行っている室内機全体の要求能力が冷房運転を行っている室内機全体の要求能力よりも小さければ（Ｓ５−ＮＯ）、Ｓ１に戻る。Ｓ６では、室外機２ａに備えた室外機制御部は、四方弁２２ａ〜２２ｃを切換える（ＯＮ→ＯＦＦ）。Ｓ６において四方弁２２ａ〜２２ｃを切換えた後、室外機２ａに備えた室外機制御部は、停止していた圧縮機を運転させたのち、運転していた圧縮機を停止させることによって、運転を行う圧縮機を変更する（Ｓ７）。Ｓ７において運転を行う圧縮機を変更した後、Ｓ９に移行する。なお、運転を行う圧縮機は予め定めた順番により変更される。 In S5, the outdoor unit controller provided in the outdoor unit 2a determines whether or not the required capacity of the entire indoor unit performing the heating operation is equal to or greater than the required capacity of the entire indoor unit performing the cooling operation. If the required capacity of the entire indoor unit performing the heating operation is equal to or greater than the required capacity of the entire indoor unit performing the cooling operation (S5-YES), the process proceeds to S6 and the entire indoor unit performing the heating operation is If the required capacity is smaller than the required capacity of the entire indoor unit performing the cooling operation (S5-NO), the process returns to S1. In S6, the outdoor unit controller provided in the outdoor unit 2a switches the four-way valves 22a to 22c (ON → OFF). After switching the four-way valves 22a to 22c in S6, the outdoor unit controller provided in the outdoor unit 2a operates the compressor by operating the stopped compressor and then stopping the operating compressor. The compressor to be performed is changed (S7). After changing the compressor which operates in S7, it transfers to S9. Note that the compressor to be operated is changed in a predetermined order.

Ｓ８では、室外機２ａに備えた室外機制御部は、２台または３台の圧縮機を運転しているときの各々の室外機における通常の運転に関する制御を行い、Ｓ１のステップに戻る。なお、通常の運転に関する制御とは、室外機２ａに備えた室外機制御部が、使用者による設定温度や風量の指示等といった運転指示内容や、室内機や室外機に備えられた各種センサでの検出値に応じて、圧縮機の回転数制御や室外膨張弁の開度制御等の制御を行うことである。Ｓ９では、室外機２ａに備えた室外機制御部は、各室内機に備えた室内機制御部からの制御信号により運転停止の指示があるか否かを判断する。運転停止の指示があれば（Ｓ９−ＹＥＳ）、本フローチャートによる制御を終了し、運転停止の指示がなければ（Ｓ９−ＮＯ）、Ｓ１のステップに戻る。 In S8, the outdoor unit controller provided in the outdoor unit 2a performs control related to normal operation in each of the outdoor units when operating two or three compressors, and returns to step S1. Note that control related to normal operation refers to operation instruction contents such as a set temperature and air volume instruction by the user, and various sensors provided in the indoor unit and outdoor unit. The control of the rotational speed of the compressor and the opening degree control of the outdoor expansion valve is performed according to the detected value. In S9, the outdoor unit controller provided in the outdoor unit 2a determines whether or not there is an instruction to stop the operation based on a control signal from the indoor unit controller provided in each indoor unit. If there is an instruction to stop operation (S9-YES), the control according to this flowchart is terminated. If there is no instruction to stop operation (S9-NO), the process returns to the step of S1.

以上説明してきた本発明の多室形空気調和装置１によれば、室外機２ａに備えた室外機制御部は、３台の室外機２ａ〜２ｃのうち、停止している圧縮機を備えた室外機が存在しているとき、四方弁２２ａ〜２２ｃの切換によって、室外熱交換器２３ａ〜２３ｃの機能を凝縮器から蒸発器へ変更した場合に、停止していた圧縮機を運転させたのち、運転していた圧縮機を停止させる制御を行う。この運転制御によって、各室外機２ａ〜２ｃのアキュムレータ２４ａ〜２４ｃに冷媒を分散することができ、四方弁の切換え前に運転していた圧縮機を備えた室外機のアキュムレータへの冷媒の集中を抑えることができるため、四方弁の切換え前に運転していた圧縮機を備えた室外機のアキュムレータのオーバーフローを防止することができる。この結果、四方弁の切換え前に運転していた圧縮機を備えた室外機におけるアキュムレータに連通する圧縮機への液バックの発生を防止することができる。 According to the multi-room air conditioner 1 of the present invention described above, the outdoor unit control unit provided in the outdoor unit 2a includes a compressor that is stopped among the three outdoor units 2a to 2c. When the outdoor unit is present, after the function of the outdoor heat exchangers 23a to 23c is changed from the condenser to the evaporator by switching the four-way valves 22a to 22c, the stopped compressor is operated. Control to stop the compressor that was in operation. By this operation control, the refrigerant can be dispersed in the accumulators 24a to 24c of the outdoor units 2a to 2c, and the concentration of the refrigerant on the accumulators of the outdoor units equipped with the compressor that was operating before the switching of the four-way valve can be reduced. Since it can suppress, the overflow of the accumulator of the outdoor unit provided with the compressor operated before switching of the four-way valve can be prevented. As a result, it is possible to prevent the occurrence of liquid back to the compressor that communicates with the accumulator in the outdoor unit equipped with the compressor that was operating before the switching of the four-way valve.

なお、本実施形態における多室形空気調和装置１では、３台の室外機２ａ〜２ｃと５台の室内機８ａ〜８ｅとを設けた冷暖房フリーの運転が行える多室形空気調和装置を例に挙げて説明したが、本発明はこれに限らず、２台または４台以上の室外機といった複数の室外機と、２〜４台または６台以上の室内機といった複数の室内機とを設けた冷暖房フリーの運転が行える多室形空気調和装置においても適用可能である。また、複数の室外機と複数の室内機とを設けた冷暖房フリーの運転が行えない、全ての室内機が冷房運転または暖房運転のいずれか一方の運転を行う多室形空気調和装置においても適用可能である。また、本実施形態における多室形空気調和装置１では、各室外機２ａ〜２ｃにそれぞれ室外機制御部を備え、親機である室外機２ａに備えた室外機制御部が、子機である室外機２ｂおよび２ｃに備えた室外機制御部との間で制御信号のやりとりを行うようにしたが、本発明はこれに限らず、各室外機２ａ〜２ｃとの間で集中制御する１つの室外機制御部を設けてもよい。 In addition, in the multi-room air conditioner 1 in this embodiment, the multi-room air conditioner which can perform the heating-free operation provided with the three outdoor units 2a-2c and the five indoor units 8a-8e is an example. However, the present invention is not limited to this, and a plurality of outdoor units such as two or four or more outdoor units and a plurality of indoor units such as two to four or six or more indoor units are provided. The present invention can also be applied to a multi-room air conditioner that can be operated free of air conditioning. Also applicable to a multi-room air conditioner in which all indoor units cannot perform cooling / heating-free operation with multiple outdoor units and multiple indoor units, and all indoor units perform either cooling operation or heating operation. Is possible. Moreover, in the multi-room air conditioner 1 in this embodiment, each outdoor unit 2a-2c is provided with the outdoor unit control part, respectively, and the outdoor unit control part with which the outdoor unit 2a which is a main | base station is a subunit | mobile_unit. The control signals are exchanged with the outdoor unit controllers provided in the outdoor units 2b and 2c. However, the present invention is not limited to this, and the single unit that performs centralized control with each of the outdoor units 2a to 2c. An outdoor unit control unit may be provided.

さらに、本実施形態における多室形空気調和装置１では、３台の室外機２ａ〜２ｃのうち、１台の室外機に備えた圧縮機のみを運転しているとき、四方弁２２ａ〜２２ｃの切換によって、室外熱交換器の機能を凝縮器から蒸発器へ変更する場合、停止していた圧縮機を運転させたのち、運転していた圧縮機を停止させるようにしたが、本発明はこれに限らない。例えば、３台の室外機２ａ〜２ｃのうち、２台の室外機に備えた各々の圧縮機を運転しているときや、５台の室外機のうち、２台の室外機に備えた各々の圧縮機を運転しているときに、四方弁２２ａ〜２２ｃの切換によって、室外熱交換器の機能を凝縮器から蒸発器へ変更する場合、運転させる２台の圧縮機について予めローテーションのパターンを決めておき、これに従って２台の圧縮機を運転するようにしてもよい。また、３台の室外機に備えた各々の圧縮機を運転しているときに、四方弁２２ａ〜２２ｃの切換によって、室外熱交換器の機能を凝縮器から蒸発器へ変更する場合、運転させる３台の圧縮機について予めローテーションのパターンを決めておき、これに従って３台の圧縮機を運転するようにしてもよい。 Furthermore, in the multi-room air conditioner 1 according to the present embodiment, when only the compressor provided in one outdoor unit among the three outdoor units 2a to 2c is operated, the four-way valves 22a to 22c When the function of the outdoor heat exchanger is changed from the condenser to the evaporator by switching, the compressor that has been stopped is operated after the compressor that has been stopped is operated. Not limited to. For example, when operating each compressor provided in two outdoor units among the three outdoor units 2a to 2c, or each provided in two outdoor units out of five outdoor units When the function of the outdoor heat exchanger is changed from the condenser to the evaporator by switching the four-way valves 22a to 22c, the rotation pattern is set in advance for the two compressors to be operated. It is possible to determine and operate the two compressors according to this. In addition, when each of the compressors provided in the three outdoor units is operating, the operation of the outdoor heat exchanger is changed from the condenser to the evaporator by switching the four-way valves 22a to 22c. A rotation pattern may be determined in advance for the three compressors, and the three compressors may be operated according to this.

１多室形空気調和装置
２ａ〜２ｃ室外機
６ａ〜６ｅ分流ユニット
８ａ〜８ｅ室内機
２１ａ〜２１ｃ圧縮機
２２ａ〜２２ｃ四方弁
２３ａ〜２３ｃ室外熱交換器
２４ａ〜２４ｃアキュムレータ
２６ａ〜２６ｃ室外ファン
２７ａ〜２７ｃ室外膨張弁
３１低圧ガス管
３１ａ〜３１ｃ低圧ガス分岐管
３４ａ〜３４ｃ室外機低圧ガス管
３６ａ〜３６ｃ接続管
３７ａ〜３７ｃ接続管
６１ａ〜６１ｅ第１電磁弁
６２ａ〜６２ｅ第２電磁弁
６３ａ〜６３ｅ第１分流管
６４ａ〜６４ｅ第２分流管
７１低圧ガス分岐器
８１ａ〜８１ｅ室内熱交換器
８２ａ〜８２ｅ室内膨張弁
８３ａ〜８３ｅ室内ファン DESCRIPTION OF SYMBOLS 1 Multi-room type air conditioner 2a-2c Outdoor unit 6a-6e Splitting unit 8a-8e Indoor unit 21a-21c Compressor 22a-22c Four-way valve 23a-23c Outdoor heat exchanger 24a-24c Accumulator 26a-26c Outdoor fan 27a- 27c Outdoor expansion valve 31 Low pressure gas pipe 31a to 31c Low pressure gas branch pipe 34a to 34c Outdoor unit low pressure gas pipe 36a to 36c Connection pipe 37a to 37c Connection pipe 61a to 61e First solenoid valve 62a to 62e Second solenoid valve 63a to 63e 1st branch pipe 64a-64e 2nd branch pipe 71 Low-pressure gas branch device 81a-81e Indoor heat exchanger 82a-82e Indoor expansion valve 83a-83e Indoor fan

Claims

A plurality of outdoor units including a compressor, an outdoor heat exchanger, a flow path switching valve, and an accumulator; a plurality of indoor units including an indoor heat exchanger; and a control unit that controls the plurality of outdoor units. A multi-room air conditioner configured by connecting the outdoor unit and a plurality of the indoor units by refrigerant piping,
When there is an outdoor unit that does not have an operating compressor among the plurality of outdoor units, the control means switches the function of the outdoor heat exchanger from the condenser to the evaporator by switching the flow path switching valve. In the multi-room air conditioner, the compressor to be operated is changed to a compressor provided in an outdoor unit that does not include the operating compressor.

The control means operates the compressors that have been stopped in a predetermined order each time the function of the outdoor heat exchanger is changed from a condenser to an evaporator by switching the flow path switching valve. The multi-room air conditioner according to claim 1.