JP2727790B2 - Defrosting operation control device for refrigeration equipment - Google Patents

Defrosting operation control device for refrigeration equipment

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Publication number
JP2727790B2
JP2727790B2 JP3112921A JP11292191A JP2727790B2 JP 2727790 B2 JP2727790 B2 JP 2727790B2 JP 3112921 A JP3112921 A JP 3112921A JP 11292191 A JP11292191 A JP 11292191A JP 2727790 B2 JP2727790 B2 JP 2727790B2
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JP
Japan
Prior art keywords
defrosting operation
refrigerant
evaporator
temperature
frost
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
JP3112921A
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Japanese (ja)
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JPH04344085A (en
Inventor
政樹 山本
伸一 中石
博 岡田
洋 朝妻
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Daikin Industries Ltd
Original Assignee
Daikin Kogyo Co Ltd
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Application filed by Daikin Kogyo Co Ltd filed Critical Daikin Kogyo Co Ltd
Priority to JP3112921A priority Critical patent/JP2727790B2/en
Publication of JPH04344085A publication Critical patent/JPH04344085A/en
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Publication of JP2727790B2 publication Critical patent/JP2727790B2/en
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Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【０００１】[0001]

【産業上の利用分野】本発明は、複数の蒸発器を備えた
冷凍装置における除霜運転制御装置の改良に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a defrosting operation control device for a refrigeration system having a plurality of evaporators.

【０００２】[0002]

【従来の技術】従来より、例えば特開昭６０−２３５９
６４号公報に開示される如く、圧縮機、凝縮器、膨張器
としての電動膨張弁及び蒸発器を順次接続し、かつ冷媒
循環方向が正サイクルと逆サイクルとに切り換わるよう
に構成された冷媒回路を備えた空気調和装置において、
暖房運転時には電動膨張弁の開度を冷媒の過熱度に基づ
き制御する一方、暖房運転中に蒸発器が着霜したときに
その着霜を融解すべくサイクルを切換えて蒸発器にホッ
トガスを導入する除霜運転時には、電動膨張弁の開度を
全開に制御することにより、蒸発器の過熱量を最大にし
て、除霜運転時間をなるべく短く済ませようとするもの
は、公知の技術である。2. Description of the Related Art Conventionally, for example, Japanese Patent Application Laid-Open No. 60-2359
No. 64, a compressor, a condenser, an electric expansion valve as an expander and an evaporator are sequentially connected, and a refrigerant
The circulation direction switches between forward and reverse cycles
In an air conditioner provided with a refrigerant circuit configured in,
During the heating operation, the opening of the electric expansion valve is controlled based on the degree of superheat of the refrigerant, and when the evaporator is frosted during the heating operation, the cycle is switched to melt the frost and hot gas is introduced into the evaporator. It is a known technique to control the opening degree of the electric expansion valve to the fully opened state during the defrosting operation to maximize the amount of overheating of the evaporator and to shorten the defrosting operation time as much as possible.

【０００３】[0003]

【発明が解決しようとする課題】ところで、冷媒回路中
に複数の蒸発器を互いに並列に配設した冷凍装置におい
て、上記公報のものを適用すると、除霜運転によって一
つの蒸発器の着霜が融解しても、他の蒸発器の着霜が融
解していないことがある。すなわち、除霜運転中におけ
る各蒸発器の加熱能力が異なれば着霜の融解度合いは異
なる。By the way, in a refrigeration system in which a plurality of evaporators are arranged in parallel in a refrigerant circuit, when the above-mentioned publication is applied, frost formation of one evaporator is caused by a defrosting operation. Even when thawed, frost formation on other evaporators may not be thawed. That is, if the heating capacity of each evaporator during the defrosting operation is different, the degree of melting of frost differs.

【０００４】特に、室外ユニットに複数の熱源側熱交換
器を組み込んで、暖房運転時に蒸発器となる各熱源側熱
交換器から冷風を室外に吹出すようにした空気調和装置
においても、通常は弁開度が同じ全開であればいずれの
熱源側熱交換器に対する着霜の融解能力もほぼ等しいは
ずであるが、周囲の建物との関係等でファンの送風に偏
流をきたすことがあり、このような原因等により、一つ
の熱源側熱交換器が着霜しても、他の熱源側熱交換器で
はまだ着霜していないことが生じる。このような場合、
いずれの熱源側熱交換器の着霜も解除されるまで除霜運
転を続行すると、除霜時間が長くなり、冷凍装置全体の
運転効率が悪化する一方、いずれかの熱源側熱交換器の
着霜が融解したときに除霜運転を終了させると、他の熱
源側熱交換器では残留フロストを生じ、その蓄積により
信頼性を悪化させるという問題がある。[0004] In particular, an air conditioner in which a plurality of heat source side heat exchangers are incorporated in an outdoor unit so that cool air is blown out of the outdoor from each heat source side heat exchanger which becomes an evaporator during a heating operation is usually used. If the valve opening is the same and the valve is fully open, the melting ability of frost on any heat source side heat exchanger should be almost the same, but due to the relationship with the surrounding buildings etc. Due to such causes, even if one heat source side heat exchanger is frosted, the other heat source side heat exchanger may not be frosted yet. In such a case,
If the defrosting operation is continued until the defrosting of any of the heat source side heat exchangers is released, the defrosting time is prolonged, and the operating efficiency of the entire refrigeration system is deteriorated. If the defrosting operation is terminated when the frost is melted, there is a problem that the residual frost is generated in the other heat source side heat exchangers, and the accumulated frost deteriorates the reliability.

【０００５】また、上記のように蒸発器の送風ファンの
偏流がある場合、除霜運転中における蒸発器の凝縮能力
が低減する結果、高圧の過上昇による高圧カットを招
き、信頼性を損ねる虞れもあった。[0005] Further, when there is a drift in the blower fan of the evaporator as described above, the condensing ability of the evaporator during the defrosting operation is reduced. There was also.

【０００６】本発明は斯かる点に鑑みてなされたもので
あり、その目的は、除霜運転中において、除霜運転から
通常運転に復帰させるに際して適切な制御を行うことに
より、冷凍装置の信頼性の向上を図ることになる。SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to perform appropriate control when returning from defrosting operation to normal operation during defrosting operation, thereby improving the reliability of the refrigeration system. The property is to be improved.

【０００７】[0007]

【課題を解決するための手段】上記目的を達成するた
め、請求項１記載の発明の講じた手段は、図１に示すよ
うに、圧縮機（１）及び凝縮器が接続された主冷媒配管
（１１）に、蒸発器（６ａ）と電動膨張弁（８ａ）とが
直列に接続された蒸発側冷媒配管（１１ａ）を接続して
閉回路に構成すると共に、上記主冷媒配管（１１）に、
蒸発器（６ｂ）と電動膨張弁（８ｂ）とが直列に接続さ
れた１つ以上の分岐配管（１１ｂ）を上記蒸発側冷媒配
管（１１ａ）に対して並列に接続し、かつ冷媒循環方向
が正サイクルと逆サイクルとに切り換わるように構成さ
れた冷媒回路（１４）を備えた冷凍装置を前提とする。To achieve the above object, according to an aspect of, means taken in the invention of claim 1, wherein, as shown in FIG. 1, the main refrigerant pipe compressor (1) and the condenser is connected In (11), the evaporator (6a) and the electric expansion valve (8a)
By connecting the evaporation side refrigerant pipe (11a) connected in series,
In addition to forming a closed circuit, the main refrigerant pipe (11)
The evaporator (6b) and the electric expansion valve (8b) are connected in series.
One or more branch pipes (11b) connected to the evaporation-side refrigerant distribution pipe.
Connected in parallel to the pipe (11a) and in the refrigerant circulation direction
Is a refrigeration apparatus provided with a refrigerant circuit (14) configured to switch between a normal cycle and a reverse cycle .

【０００８】そして、該冷凍装置の運転中に、除霜運転
指令を受けて逆サイクルによる除霜運転を行うように制
御する除霜運転制御手段（５１Ａ）を備えている。[0008] Then, during the operation of the refrigeration system, and a control <br/> Gosuru defrosting operation control means so as to perform the defrosting operation by the reverse cycle undergoing defrosting operation command (51A).

【０００９】さらに、上記各蒸発器（６ａ，６ｂ）の温
度又は該温度に関連する冷媒状態量から蒸発器（６ａ，
６ｂ）の着霜状態を個別に検出する着霜状態検出手段
（Th21，Th22）と、上記圧縮機（１）の吐出冷媒圧力を
検出する吐出圧力検出手段（Ｐ１）とを備えている。加
えて、上記除霜運転制御手段（５１Ａ）による除霜運転
中に、各着霜状態検出手段（Th21，Th22）の出力を受
け、いずれかの蒸発器（６ａ又は６ｂ）の温度が着霜の
融解温度に達したとき、当該蒸発器（６ａ又は６ｂ）の
電動膨張弁（８ａ又は８ｂ）の開度を絞るように制御す
る開度低減手段（５２）をを備えている。その上、上記
除霜運転制御手段（５１Ａ）による除霜運転中に、上記
各着霜状態検出手段（Th21，Th22）及び吐出圧力検出手
段（Ｐ１）の出力を受け、すべての蒸発器（６ａ，６
ｂ）の温度が着霜の融解温度に達するか、又は吐出冷媒
圧力が所定値よりも高くなったときに、除霜運転を終了
して通常運転に復帰するように制御する復帰制御手段
（５３Ｂ）を備えている。Furthermore, each of the evaporator (6a, 6b) evaporator from the refrigerant state quantity related to the temperature or temperature of the (6a,
A frost condition detecting means for detecting individually the frosting condition of 6b) (Th21, Th22), and a discharge pressure detection means for detecting (P1) of the discharge refrigerant pressure of the compressor (1). In addition, during the defrosting operation by the defrosting operation control means (51A), the temperature of receiving the output of the frost condition detecting means (Th21, Th 22), one evaporator (6a or 6b) is frosted upon reaching the melting temperature, and the evaporator of the electric expansion valve (6a or 6b) opening reducing means controls to narrow the opening of (8a or 8b) (52) comprising a. Moreover, during the defrosting operation by the defrosting operation control means (51A), each frosting state detecting means (Th21, Th 22) and receiving an output of the discharge pressure detecting means (P1), all evaporator (6a , 6
When the temperature of b) reaches the melting temperature of frost formation or when the pressure of the discharged refrigerant becomes higher than a predetermined value , the return control means (53B) controls to end the defrosting operation and return to the normal operation. ) is equipped with a.

【００１０】[0010]

【作用】以上の構成により、請求項１記載の発明では、
冷凍装置の運転中、除霜運転開始指令に応じて、除霜運
転制御手段（５１Ａ）により、逆サイクルによる除霜運
転が行われる。そして、除霜運転制御手段（５１Ａ）に
よる除霜運転中、いずれかの蒸発器（例えば６ｂ）の温
度が融解温度に達すると、開度低減手段（５２）によ
り、当該蒸発器（６ｂ）の電動膨張弁（８ｂ）の開度が
絞られるので、当該蒸発器（６ｂ）への冷媒循環量が減
少し、その分他の蒸発器（６ａ）への冷媒循環量が増大
する。したがって、各蒸発器（６ａ，６ｂ）の着霜の融
解度合いが可及的に均一化され、除霜運転時間が短縮さ
れて、冷凍装置の運転効率が向上するとともに、着霜の
融解が遅い蒸発器（例えば６ａ）の残留フロストが低減
し、信頼性が向上することになる。According to the above-mentioned structure, according to the first aspect of the present invention,
During operation of the refrigeration apparatus, the defrosting operation control means (51A) performs a defrosting operation in a reverse cycle according to a defrosting operation start command. When the temperature of any of the evaporators (for example, 6b) reaches the melting temperature during the defrosting operation by the defrosting operation control means (51A), the opening degree reducing means (52) causes the evaporator (6b) to operate. Since the opening of the electric expansion valve (8b) is reduced, the amount of refrigerant circulating to the evaporator (6b) decreases, and the amount of refrigerant circulating to the other evaporator (6a) increases accordingly. Therefore, the degree of frost melting of each evaporator (6a , 6b) is made as uniform as possible, the defrosting operation time is shortened, the operation efficiency of the refrigeration system is improved, and the frost melting is slow. The residual frost of the evaporator (for example, 6a) is reduced, and the reliability is improved.

【００１１】また、その後、復帰制御手段（５３Ｂ）に
より、すべての蒸発器（６ａ，６ｂ）の温度が着霜の融
解温度に達するか、吐出圧力検出手段（Ｐ１）で検出さ
れる吐出冷媒圧力が所定圧力よりも高くなったときに、
除霜運転を終了して通常運転に復帰するように制御され
る。したがって、各蒸発器（６ａ，６ｂ）の着霜の融解
度合いが均一化されるとともに、高圧側圧力の過上昇が
防止され、高圧カットによる異常停止が回避され、信頼
性が顕著に向上することになる。Thereafter, the return control means (53B) determines whether the temperature of all the evaporators (6a , 6b) reaches the melting temperature of frost formation or the discharge refrigerant pressure detected by the discharge pressure detection means (P1). When is higher than the predetermined pressure,
Control is performed so that the defrosting operation is terminated and the operation returns to the normal operation. Therefore, the degree of frost melting of each evaporator (6a , 6b) is made uniform, and the high pressure side pressure is prevented from excessively rising, abnormal stop due to high pressure cut is avoided, and reliability is remarkably improved. become.

【００１２】[0012]

【実施例】以下、本発明の実施例について、図２以下の
図面に基づき説明する。DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS.

【００１３】図２は本発明の実施例に係るマルチ型空気
調和装置の冷媒配管系統を示し、一台の室外ユニット
（Ａ）に対して複数の室内ユニット（図示せず）が並列
に接続されている。FIG. 2 shows a refrigerant piping system of the multi-type air conditioner according to the embodiment of the present invention. A plurality of indoor units (not shown) are connected in parallel to one outdoor unit (A). ing.

【００１４】上記室外ユニット（Ａ）の内部には、出力
周波数を３０〜７０Ｈz の範囲で１０Ｈz 毎に可変に切
換えられるインバータ（２ａ）により容量が調整される
第１圧縮機（１ａ）と、パイロット圧の高低で差動する
アンローダ（２ｂ）により容量がフルロード（１００
％）およびアンロード（５０％）状態の２段階に調整さ
れる第２圧縮機（１ｂ）とを逆止弁（２ｃ）を介して並
列に接続して構成される容量可変な圧縮機（１）と、該
圧縮機（１）から吐出されるガス中の油を分離する油分
離器（４）と、冷房運転時には図中実線の如く切換わり
暖房運転時には図中破線の如く切換わる四路切換弁
（５）と、冷房運転時に凝縮器、暖房運転時に蒸発器と
なる２台の熱源側熱交換器（６ａ，６ｂ）と、冷房運転
時には冷媒流量を調節し、暖房運転時には冷媒の絞り作
用を行う２台の室外電動膨張弁（８ａ，８ｂ）と、液化
した冷媒を貯蔵するレシーバ（９）と、アキュムレータ
（１０）とが主要機器として配設されている。In the interior of the outdoor unit (A), a first compressor (1a) whose capacity is adjusted by an inverter (2a) whose output frequency is variably switched every 10 Hz within a range of 30 to 70 Hz, and a pilot The capacity is fully loaded (100
%) And a second compressor (1b) which is adjusted in two stages of an unload (50%) state and connected in parallel via a check valve (2c). ), An oil separator (4) for separating oil in the gas discharged from the compressor (1), and a four-way switching as shown by the solid line in the cooling operation and a switching as shown by the broken line in the heating operation. A switching valve (5), two heat source side heat exchangers (6a , 6b) serving as a condenser during a cooling operation and an evaporator during a heating operation, adjusting a refrigerant flow rate during a cooling operation, and restricting a refrigerant during a heating operation. Two outdoor motor-operated expansion valves (8a , 8b) for performing an operation, a receiver (9) for storing a liquefied refrigerant, and an accumulator (10) are provided as main devices.

【００１５】上記圧縮機（１）、レシーバ（９）及びア
キュムレータ（１０）は主冷媒配管（１１）により順次
直列に接続される一方、上記各熱源側熱交換器（６ａ，
６ｂ）及び各室外電動膨張弁（８ａ，８ｂ）はそれぞれ
２つの分岐配管（１１ａ，１１ｂ）により直列に接続さ
れている。更に、１つの分岐配管（１１ａ）が請求項１
記載の発明の蒸発側冷媒配管を構成し、上記主冷媒配管
（１１）に１つの分岐配管（１１ａ）が接続されて閉回
路を構成するとともに、該１つの分岐配管（１１ａ）と
並列に他の分岐配管（１１ｂ）が主冷媒配管（１１）に
接続されて冷媒が循環する閉回路の冷媒回路（１４）が
構成されている。そして、上記冷媒回路 （１４）は、四
路切換弁（５）の切り換わりによって冷媒循環方向が正
サイクルと逆サイクルとに切り換わるように構成されて
いる。[0015] The compressor (1), receiver (9) and accumulator (10) is a main refrigerant pipe (11) by one that will be connected sequentially in series, each of the heat source-side heat exchanger (6a,
6b) and the outdoor electric expansion valves (8a , 8b) are connected in series by two branch pipes (11a , 11b) , respectively. Furthermore, one branch pipe (11a) is provided in claim 1.
The evaporating-side refrigerant pipe according to the invention is described, and the main refrigerant pipe is formed.
One branch pipe (11a) is connected to (11) and closed
And the one branch pipe (11a)
Another branch pipe (11b) is connected to the main refrigerant pipe (11) in parallel.
A connected closed circuit refrigerant circuit (14) through which the refrigerant circulates
It is configured. The refrigerant circuit (14)
The refrigerant circulation direction is correct by switching of the passage switching valve (5).
It is configured to switch between a cycle and a reverse cycle .

【００１６】ここで、上記室外ユニット（Ａ）の各機器
は一つのケーシング（図示せず）内に収納されており、
上記各熱源側熱交換器（６ａ，６ｂ）のうち一方の熱源
側熱交換器（６ａ）は、高風量と低風量とに切換え可能
な第１ファン（３１ａ）及び定風量の第２ファン（３１
ｂ）の通風路に設置され、他方の熱源側熱交換器（６
ｂ）には、高風量と定風量とに切換え可能な第３ファン
（３１ｃ）の通風路に設置されている。そして、各熱源
側熱交換器（６ａ，６ｂ）に対応して２つの空気吹出口
が設けられ、個別に室外空気との熱交換を行うようにし
たいわゆる二面熱交換器に構成されている。Here, each device of the outdoor unit (A) is housed in one casing (not shown),
One of the heat source side heat exchangers (6a) of the heat source side heat exchangers (6a , 6b) is a first fan (31a) that can be switched between a high air volume and a low air volume and a second fan (a constant air volume). 31
b), and the other heat source side heat exchanger (6)
b) is installed in the ventilation path of the third fan (31c) that can be switched between a high air volume and a constant air volume. Two air outlets are provided corresponding to each of the heat source side heat exchangers (6a , 6b), and are configured as so-called two-sided heat exchangers that individually perform heat exchange with outdoor air. .

【００１７】次に、吐出管と液管側とを吐出ガス（ホッ
トガス）のバイパス可能に接続する暖房過負荷制御用バ
イパス路（４１）が設けられている。該バイパス路（４
１）は２つの熱源側熱交換器（６ａ，６ｂ）に対応する
２つの分岐路（４１ａ，４１ｂ）に分岐しており、これ
らは互いに同一の構成されているので、一方の分岐路
（４１ａ）についてのみ説明するに、該分岐路（４１
ａ）には、熱源側熱交換器（６ａ）と共通の空気通路に
設置された補助熱交換器（４２ａ）と、キャピラリチュ
ーブ（４３ａ）とが順次直列に接続されている。上記構
成はもう一方の分岐路（４１ｂ）についても同様であ
る。そして、暖房過負荷制御用バイパス路（４１）の合
流部に、冷媒の高圧時に開作動する電磁開閉弁（４４）
が介設されている。Next, a heating overload control bypass path (41) is provided for connecting the discharge pipe and the liquid pipe side so that the discharge gas (hot gas) can be bypassed. The bypass (4
1) is branched into two branch paths (41a , 41b) corresponding to the two heat source side heat exchangers (6a , 6b). Since these are identical to each other, one branch path (41a) is formed. ) Will be described only.
In (a), an auxiliary heat exchanger (42a) installed in a common air passage with the heat source side heat exchanger (6a) and a capillary tube (43a) are sequentially connected in series. The above configuration is the same for the other branch path (41b). An electromagnetic on-off valve (44) that opens when the refrigerant is at a high pressure is provided at the junction of the heating overload control bypass path (41).
Is interposed.

【００１８】ここで、冷房運転時には常時上記電磁開閉
弁（４４）がオンつまり開状態になって、吐出ガスの一
部を主冷媒回路（１４）から暖房過負荷制御用バイパス
路（４１）にバイパスすることにより、吐出ガスの一部
を補助熱交換器（４２ａ，４２ｂ）で凝縮させて熱源側
熱交換器（６ａ，６ｂ）の能力を補助するとともに、各
キャピラリチューブ（４３ａ，４３ｂ）で熱源側熱交換
器（６ａ，６ｂ）側の圧力損失とのバランスを取るよう
にしている。Here, during the cooling operation, the electromagnetic on-off valve (44) is always on or open, and a part of the discharged gas is transferred from the main refrigerant circuit (14) to the heating overload control bypass passage (41). By bypassing, a part of the discharge gas is condensed by the auxiliary heat exchangers (42a , 42b) to assist the capacity of the heat source side heat exchangers (6a , 6b) , and to be reduced by the respective capillary tubes (43a , 43b). The pressure loss on the heat source side heat exchanger (6a , 6b) side is balanced.

【００１９】また、暖房運転時には、高圧が過上昇した
ときに、ただちに上記電磁開閉弁（４４）を開くのでは
なく、まず、圧縮機（１）の容量を低下させ、それでも
高圧側圧力の過上昇が続行すると、一方の室外電動膨張
弁（８ａ）を全閉にすることにより、蒸発能力を下げ
て、室内側の低能力状態に対応させるようにしている。
そして、上記室外電動膨張弁（８ａ）の全閉制御によっ
ても、過負荷状態が解消しないときのみ、電磁開閉弁
（４４）を開いて、吐出ガスの一部を各補助熱交換器
（４２ａ，４２ｂ）で凝縮させて熱源側熱交換器（６
ｂ）の蒸発能力とのバランスを取るようになされてい
る。In the heating operation, when the high pressure rises excessively, instead of immediately opening the solenoid on-off valve (44), first, the capacity of the compressor (1) is reduced. If the ascent continues, the one outdoor electric expansion valve (8a) is fully closed to lower the evaporation capacity to correspond to the low capacity state on the indoor side.
Only when the overload state is not resolved even by the full-closed control of the outdoor electric expansion valve (8a), the electromagnetic on-off valve (44) is opened and a part of the discharge gas is supplied to each of the auxiliary heat exchangers (42a , 42a , 42a) . 42b) and condensed in the heat source side heat exchanger (6
The balance is made with the evaporation capacity of b).

【００２０】さらに、（５１）は主冷媒回路（１４）の
液ラインと各圧縮機（１ａ，１ｂ）の吸入側との間を接
続し、冷暖房運転時に吸入ガスの過熱度を調節するため
のリキッドインジェクションバイパス路であって、該各
バイパス路（５１）は途中で二つの分岐路（５１ａ，５
１ｂ）に分岐し、分岐路（５１ａ，５１ｂ）には、各圧
縮機（１ａ，１ｂ）のオン・オフと連動して開閉するイ
ンジェクション用電磁弁（５２ａ，５２ｂ）と、キャピ
ラリチューブ（５３ａ，５３ｂ）とがそれぞれ介設され
ている。Further, (51) connects between the liquid line of the main refrigerant circuit (14) and the suction side of each of the compressors (1a , 1b) to adjust the degree of superheat of the suction gas during the cooling and heating operation. A liquid injection bypass passage, wherein each of the bypass passages (51) is provided with two branch passages (51a , 5
1b), and the branch passages (51a , 51b) include an injection solenoid valve (52a , 52b) that opens and closes in conjunction with ON / OFF of each compressor (1a , 1b), and a capillary tube (53a , 51b) . 53b) are interposed.

【００２１】また、（１５）は、吸入管中の吸入冷媒と
液管中の液冷媒との熱交換により吸入冷媒を冷却させ
て、連絡配管における冷媒の過熱度の上昇を補償するた
めの吸入管熱交換器である。(15) The suction for cooling the suction refrigerant by heat exchange between the suction refrigerant in the suction pipe and the liquid refrigerant in the liquid pipe to compensate for an increase in the degree of superheat of the refrigerant in the communication pipe. It is a tube heat exchanger.

【００２２】なお、上記各主要機器以外に補助用の諸機
器が設けられている。（７ａ，７ｂ）は各熱源側熱交換
器（６ａ，６ｂ）の液側入口に設けられた過冷却器、
（２１）は第２圧縮機（１ｂ）のバイパス路（２０）に
介設されて、第２圧縮機（１ｂ）の停止時およびアンロ
ード状態時に「開」となり、フルロード状態で「閉」と
なるアンローダ用電磁弁、（２２）は上記バイパス路
（２０）に介設されたキャピラリチューブ、（２４）は
吐出管と吸入管とを接続する均圧ホットガスバイパス路
（２３）に介設されて、サーモオフ状態等による圧縮機
（１）の停止時、再起動前に一定時間開作動する均圧用
電磁弁、（２５）はキャピラリチューブ（２６）を介し
て上記油分離器（４）から各圧縮機（１ａ，１ｂ）に油
を戻すための油戻し管、（２７）はキャピラリチューブ
（２８）を介して各圧縮機（１ａ，１ｂ）のドーム間を
接続する均油管である。In addition, auxiliary devices are provided in addition to the above main devices. (7a , 7b) is a subcooler provided at the liquid side inlet of each heat source side heat exchanger (6a , 6b),
(21) is interposed in the bypass path (20) of the second compressor (1b), and is "open" when the second compressor (1b) is stopped and in the unloaded state, and "closed" in the full load state. An unloader solenoid valve, (22) a capillary tube provided in the bypass passage (20), and (24) provided in a pressure equalizing hot gas bypass passage (23) connecting the discharge pipe and the suction pipe. Then, when the compressor (1) is stopped due to a thermo-off state or the like, the pressure equalizing solenoid valve is opened for a predetermined time before restarting, and (25) is connected to the oil separator (4) through a capillary tube (26). An oil return pipe for returning oil to each of the compressors (1a , 1b), and an oil return pipe (27) for connecting the dome of each of the compressors (1a , 1b) via a capillary tube (28).

【００２３】さらに、空気調和装置にはセンサ類が配置
されていて、（Th１）は室外ユニット（Ａ）のケーシン
グ外面に設置され、室外空気の温度Ｔ１を検出する外気
サーミスタ、（Th21，Th22）はそれぞれ各熱源側熱交換
器（６ａ，６ｂ）の液管側に配設され、熱源側熱交換器
（６ａ，６ｂ）が蒸発器となる暖房運転時には各熱源側
熱交換器（６ａ，６ｂ）の温度を個別に検出するディア
イサ、（Th31，Th32）はそれぞれ各圧縮機（１ａ，１
ｂ）の吐出管に配置され、吐出冷媒の温度を検出する吐
出管サーミスタ、（Th41，Th42）はそれぞれ各分岐配管
（１１ａ，１１ｂ）のガス側つまり暖房運転時に吸入ラ
インとなる部位に配置され、吸入される過熱冷媒の温度
を検出する吸入管サーミスタ、（Ｐ１）は吐出ラインに
配置され、高圧側圧力（吐出冷媒圧力）を検出する吐出
圧力検出手段としての高圧圧力センサ、（Ｐ２）は吸入
ラインに配置され、低圧側圧力を検出する低圧圧力セン
サである。Further, sensors are arranged in the air conditioner, and (Th1) is installed on the outer surface of the casing of the outdoor unit (A) to detect an outdoor air temperature T1. (Th21 , Th22) disposed in the liquid pipe of each heat source side heat exchanger, respectively (6a, 6b), the heat source-side heat exchanger (6a, 6b) each heat source side heat exchanger during heating operation as an evaporator (6a, 6b ) For detecting the temperature of each of the compressors (1a , 1).
The discharge pipe thermistor (Th41 , Th42), which is disposed in the discharge pipe of (b) and detects the temperature of the discharged refrigerant, is disposed on the gas side of each branch pipe (11a , 11b), that is, a part which becomes the suction line during the heating operation. A suction pipe thermistor for detecting the temperature of the superheated refrigerant to be sucked in; (P1) a high-pressure pressure sensor as discharge pressure detection means arranged in the discharge line and detecting a high-pressure side pressure (discharge refrigerant pressure); This is a low-pressure sensor that is arranged in the suction line and detects a low-pressure side pressure.

【００２４】なお、空気調和装置の暖房運転時、上記各
吸入管サーミスタ（Th41，Th42）で検出される過熱冷媒
温度Ｔ４と、各ディアイサ（Th21，Th22）で検出される
蒸発温度Ｔ2n（ｎ＝１，２）との温度差から冷媒の過熱
度Ｓｈを検出するようになされている。In the heating operation of the air conditioner, the superheated refrigerant temperature T4 detected by each of the suction pipe thermistors (Th41 , Th42) and the evaporation temperature T2n (n = n) detected by each of the deicers (Th21 , Th22). The degree of superheat Sh of the refrigerant is detected from the temperature difference between (1) and (2).

【００２５】上記各センサは、空気調和装置の運転を制
御するコントローラ（図示せず）に信号線で接続されて
おり、コントローラにより、各センサで検出される冷媒
等の状態に応じて、各機器の作動を制御するようになさ
れている。Each of the above sensors is connected by a signal line to a controller (not shown) for controlling the operation of the air conditioner, and the controller controls each device according to the state of the refrigerant and the like detected by each sensor. The operation of is controlled.

【００２６】空気調和装置の暖房運転時、四路切換弁
（５）の接続状態が図中破線側に切換わり、圧縮機
（１）から吐出されるガス冷媒が室内ユニットで室内空
気との熱交換により凝縮，液化され、液冷媒となってレ
シーバ（９）に貯溜された後、各分岐配管（１１ａ，１
１ｂ）に分岐して流れ、各室外電動膨張弁（８ａ，８
ｂ）で減圧され、各熱源側熱交換器（６ａ，６ｂ）で蒸
発して圧縮機（１）に吸入されるように循環する。ま
た、冷房運転時には、四路切換弁（５）が図中実線側に
切換わり、冷媒の循環方向は上記冷房運転時とは逆向き
となって、吐出冷媒が各分岐配管（１１ａ，１１ｂ）に
分岐して流れ、各熱源側熱交換器（６ａ，６ｂ）で室外
空気との熱交換により凝縮，液化され、レシーバ（９）
に貯溜された後、室内ユニットで室内空気との熱交換に
よりガス冷媒となって圧縮機（１）に戻るように循環す
る。During the heating operation of the air conditioner, the connection state of the four-way switching valve (5) is switched to the broken line side in the drawing, and the gas refrigerant discharged from the compressor (1) is heated by the indoor unit to the indoor air. After being exchanged, it is condensed and liquefied, becomes a liquid refrigerant, and is stored in the receiver (9). Then, each branch pipe (11a , 1)
1b) and flows to each outdoor electric expansion valve (8a , 8).
The pressure is reduced in b) and the heat is circulated so as to evaporate in each heat source side heat exchanger (6a , 6b) and to be sucked into the compressor (1). Further, during the cooling operation, the four-way switching valve (5) is switched to the solid line side in the drawing, and the circulation direction of the refrigerant is opposite to that during the cooling operation, and the discharged refrigerant is supplied to each branch pipe (11a , 11b). And is condensed and liquefied by heat exchange with outdoor air in each of the heat source side heat exchangers (6a , 6b).
After being stored in the indoor unit, the indoor unit circulates back to the compressor (1) as a gas refrigerant by heat exchange with indoor air.

【００２７】次に、請求項１記載の発明に係る制御につ
いて、図３〜図５のフローチャートに基づき説明する。Next, the control according to the first aspect of the present invention will be described with reference to the flowcharts of FIGS.

【００２８】図３は除霜運転時におけるディアイサ（Th
21，Th22）の代表値Ｔ２を決定するための制御の内容を
示し、ステップＳＰ１で、各ディアイサ（Th21，Th22）
側で検出されるディアイサ温度Ｔ21，Ｔ22同士の高低を
比較し、Ｔ21＞Ｔ22であれば、ステップＳＰ２でＴ２＝
Ｔ22とし、Ｔ21＜Ｔ22であれば、ステップＳＰ３でＴ２
＝Ｔ21とする。つまり、各ディアイサ（Th21，Th22）の
検出値Ｔ21，Ｔ21のうち、低いほうを代表値Ｔ２として
決定する。FIG. 3 shows a deicer (Th) during the defrosting operation.
21 and the content of control for determining the representative value T2 of Th22) are shown. In step SP1, each deicer (Th21, Th22) is determined.
The levels of the deicer temperatures T21 and T22 detected on the side are compared, and if T21> T22, T2 = T2 = T2 = T2 in step SP2.
T22 is set, and if T21 <T22, T2 is set in step SP3.
= T21. That is, the lower one of the detected values T21 and T21 of each of the deicers (Th21 and Th22) is determined as the representative value T2.

【００２９】次に、図４は空気調和装置の運転制御の内
容を示し、ステップＳＱ１，ＳＱ２及びＳＱ３で、２０
分間の設定時間を有する（除霜運転）禁止タイマ（図示
せず）がカウントアップするまでの間通常暖房運転を行
った後、ステップＳＱ４で、上記図３の代表値決定制御
で決定されたディアイサ温度の代表値Ｔ２について、式
Ｔ２＜０．５×Ｔ１−１０が成立するか否かを判別し、
この関係が成立しない間はステップＳＱ５で後述の５分
タイマ（図示せず）をリセットした後、ステップＳＱ４
に戻って、通常暖房運転を続行する。FIG. 4 shows the contents of the operation control of the air conditioner. In steps SQ1, SQ2 and SQ3,
After the normal heating operation is performed until the (defrosting operation) prohibition timer (not shown) having the set time of 1 minute counts up, in step SQ4, the deicer determined by the representative value determination control of FIG. For the representative value T2 of the temperature, it is determined whether or not the equation T2 <0.5 × T1-10 holds.
While this relationship is not established, a 5-minute timer (not shown), which will be described later, is reset in step SQ5.
Return to and continue the normal heating operation.

【００３０】一方、式Ｔ２＜０．５×Ｔ１−１０が成立
すると、いずれか一方の熱源側熱交換器（６ａ又は６
ｂ）の着霜が所定量に達したので除霜運転を行う必要が
あると判断し、ステップＳＱ６で、除霜条件が成立して
から５分間の待機を行うための５分タイマのカウントを
行って、ステップＳＱ７で、５分タイマがカウントアッ
プするまで待って、ステップＳＱ８で、除霜運転指令を
出力して除霜運転を開始する。すなわち、四路切換弁
（５）を冷房サイクル側に切換えるとともに、圧縮機
（１）の容量を最大に、各室外電動膨張弁（８ａ，８
ｂ）の開度を全開に、かつ冷媒の循環量を最大にして熱
源側熱交換器（６ａ，６ｂ）に多量のホットガスを導入
することにより、熱源側熱交換器（６ａ，６ｂ）の着霜
を融解させる。また、除霜運転の開始と同時に、除霜運
転の過剰を防止するためのガード用１０分タイマ（図示
せず）のカウントを開始する。On the other hand, if the equation T2 <0.5 × T1-10 is satisfied, one of the heat source side heat exchangers (6a or 6a)
Since it is determined that the defrosting operation needs to be performed because the frost formation of b) has reached the predetermined amount, in step SQ6, the count of the 5-minute timer for waiting for 5 minutes after the defrost condition is satisfied is counted. Then, in step SQ7, the system waits until the 5-minute timer counts up, and in step SQ8, outputs a defrosting operation command to start the defrosting operation. That is, the four-way switching valve (5) is switched to the cooling cycle side, and the capacity of the compressor (1) is maximized so that the outdoor electric expansion valves (8a , 8)
fully opened opening of b), and the heat source-side heat exchanger to maximize the quantity of the refrigerant circulating (6a, by introducing a large amount of hot gas to 6b), the heat source-side heat exchanger (6a, 6b) Thaw frost. At the same time as the start of the defrosting operation, the count of a guard 10-minute timer (not shown) for preventing the defrosting operation from being excessive is started.

【００３１】そして、ステップＳＱ９で、ディアイサ温
度の代表値Ｔ２が着霜の融解温度１２．５（℃）よりも
高いか否かを判別して、Ｔ２＞１２．５（℃）でなけれ
ば、ステップＳＱ１０に進んで上記高圧圧力センサ（Ｐ
１）で検出される高圧側圧力Ｐｃが所定値２０（Kg／cm
2 ）よりも高いか否かを判別して、Ｐｃ＞２０（Kg／cm
2 ）でなければ、さらにステップＳＱ１１で１０分タイ
マがカウントアップしたか否かを判別する。そして、１
０分タイマがカウントアップしない間は、上記ステップ
ＳＱ９の制御に戻って、上記ステップＳＱ９〜ＳＱ１１
の制御を繰り返し、その間に、Ｔ２＞１２．５（℃）が
成立するといずれの熱源側熱交換器（６ａ，６ｂ）の着
霜も融解したと判断してステップＳＱ１２に進んで通常
暖房運転に復帰し、また、Ｐｃ＞２０（Kg／cm2 ）が成
立すると高圧カットを招く虞れがあると判断してステッ
プＳＱ１２に進んで通常暖房運転に復帰し、また、１０
分タイマがタイムアップしたときには、過剰のデフロス
ト時間により空調効果が害されると判断して、ステップ
ＳＱ１２に進んで通常暖房運転に復帰する。In step SQ9, it is determined whether or not the representative value T2 of the deicer temperature is higher than the frost melting temperature 12.5 (° C.). Proceeding to step SQ10, the high pressure sensor (P
The high pressure side pressure Pc detected in 1) is a predetermined value 20 (Kg / cm
2 ) to determine whether it is higher than Pc> 20 ( Kg / cm
2 ) If not, it is further determined in step SQ11 whether or not the 10-minute timer has counted up. And 1
While the 0 minute timer does not count up, the process returns to the control in step SQ9, and returns to the control in steps SQ9 to SQ11.
When T2> 12.5 (° C.) is satisfied during this time, it is determined that the frost formation on any of the heat source side heat exchangers (6a , 6b) has been melted, and the process proceeds to step SQ12 to perform the normal heating operation. When Pc> 20 ( Kg / cm 2 ) is satisfied, it is determined that there is a risk of causing a high pressure cut, and the process proceeds to step SQ12 to return to the normal heating operation.
When the minute timer times out, it is determined that the air conditioning effect is impaired by the excessive defrost time, and the process proceeds to step SQ12 to return to the normal heating operation.

【００３２】また、図５は除霜運転中における室外電動
膨張弁（８ａ，８ｂ）の開度の制御内容を示し、ステッ
プＳＲ１で、除霜運転中か否かを判別し、除霜運転中で
あれば、ステップＳＲ２に進んで、いずれかのディアイ
サ温度Ｔ21（又はＴ22）が着霜の融解温度である所定温
度１２．５（℃）よりも高くなったか否かを判別し、Ｔ
21（又はＴ22）＞１２．５（℃）でなければ、ステップ
ＳＲ３で弁開度を全開とする一方、Ｔ21（又はＴ22）＞
１２．５（℃）であれば、ステップＳＲ４に進んで弁開
度を半開１０００パルスに設定する。なお、上記ステッ
プＳＲ１の判別で、除霜運転中でなければ、ステップＳ
Ｒ５に移行して、通常の弁開度制御を行う。つまり、暖
房運転時には過熱度Ｓｈを目標値に収束させる過熱度制
御に基づき弁開度を制御し、冷房運転時には弁開度を全
開とするように制御する。FIG. 5 shows the contents of control of the degree of opening of the outdoor electric expansion valves (8a , 8b) during the defrosting operation. At step SR1, it is determined whether or not the defrosting operation is being performed. If so, the process proceeds to step SR2, and it is determined whether or not any of the deicer temperatures T21 (or T22) has become higher than a predetermined temperature 12.5 (° C.) which is the melting temperature of frost.
If it is not 21 (or T22)> 12.5 (° C.), while the valve opening is fully opened in step SR3, T21 (or T22)>
If it is 12.5 (° C.), the routine proceeds to step SR4, where the valve opening is set to a half-open 1000 pulses. If it is determined in step SR1 that the defrosting operation is not being performed, the process proceeds to step S1.
The routine proceeds to R5, where normal valve opening control is performed. In other words, during heating operation controls based valve opening to superheat control for converging the degree of superheat Sh to the target value, at the time of cooling operation is controlled so as to fully open the valve opening.

【００３３】上記各フローチャートにおいて、ステップ
ＳＱ８の制御により、請求項１記載の発明の除霜運転制
御手段（５１Ａ）が構成され、ステップＳＲ４の制御に
より、請求項１記載の発明の開度低減手段（５２）が構
成されている。また、ステップＳＱ１１の制御により、
請求項１記載の発明の復帰制御手段（５３Ｂ）が構成さ
れている。In each of the flowcharts described above, the control of step SQ8 constitutes the defrosting operation control means (51A) of the present invention, and the control of step SR4 makes the opening reduction means of the present invention. (52) is constituted. Further, under the control of step SQ11,
The return control means (53B) according to the first aspect of the present invention is configured.

【００３４】したがって、上記実施例の請求項１記載の
発明の制御では、空気調和装置の暖房運転中、除霜運転
開始指令に応じて、除霜運転制御手段（５１Ａ）によ
り、逆サイクルによる除霜運転を行うように制御され
る。Therefore, in the control according to the first aspect of the present invention, during the heating operation of the air conditioner, the defrosting operation control means (51A) controls the defrosting by the reverse cycle in response to the defrosting operation start command. It is controlled to perform the defrosting operation.

【００３５】そのとき、除霜運転中において各室外電動
膨張弁（８ａ，８ｂ）の開度を全開に制御するもので
は、冷媒循環量が最大に維持されるが、各室外ファン
（３１ａ〜３１ｃ）による送風量は周囲の建物との関係
で偏流を生じることがある。つまり、各熱源側熱交換器
（６ａ，６ｂ）の着霜の融解度合いは均一とは限らず、
一方の熱源側熱交換器（例えば６ｂ）の着霜が融解して
いても他方の熱源側熱交換器（６ａ）の着霜が融解して
いないことがある。At this time, when the outdoor electric expansion valves (8a , 8b) are controlled to fully open during the defrosting operation, the refrigerant circulation amount is maintained at the maximum, but the outdoor fans (31a to 31c) ) May cause a drift due to the surrounding buildings. That is, the degree of frost melting of each heat source side heat exchanger (6a , 6b) is not always uniform,
Even if frost formation on one heat source side heat exchanger (for example, 6b) is melted, frost formation on the other heat source side heat exchanger (6a) may not be melted.

【００３６】ここで、本発明では、除霜運転制御手段
（５１Ａ）による除霜運転中、いずれかの熱源側熱交換
器（例えば６ｂ）の温度Ｔ22が融解温度に達すると、開
度低減手段（５２）により、当該熱源側熱交換器（６
ｂ）の室外電動膨張弁（８ｂ）の開度が絞られるので、
当該熱源側熱交換器（６ｂ）への冷媒循環量が減少し、
その分他の熱源側熱交換器（６ａ）への冷媒循環量が増
大する。したがって、各熱源側熱交換器（６ａ，６ｂ）
の着霜の融解度合いが可及的に均一化され、除霜運転時
間が短縮されるので、空気調和装置の運転効率が向上す
ることになる。また、各熱源側熱交換器（６ａ，６ｂ）
の着霜の融解度合いが均一化される結果、融解が遅い側
の残留フロストが低減し、残留フロストの蓄積による故
障等が防止され、信頼性が向上することになる。Here, in the present invention, during the defrosting operation by the defrosting operation control means (51A), when the temperature T22 of any of the heat source side heat exchangers (for example, 6b) reaches the melting temperature, the opening degree reducing means. According to (52), the heat source side heat exchanger (6)
Since the opening of the outdoor electric expansion valve (8b) of b) is narrowed,
The amount of refrigerant circulating to the heat source side heat exchanger (6b) decreases,
The refrigerant circulation amount to the other heat source side heat exchanger (6a) increases accordingly. Therefore, each heat source side heat exchanger (6a , 6b)
The degree of melting of the frost is made as uniform as possible, and the defrosting operation time is shortened, so that the operation efficiency of the air conditioner is improved. In addition, each heat source side heat exchanger (6a , 6b)
As a result, the degree of melting of the frost is made uniform, so that the residual frost on the side where the melting is slow is reduced, a failure due to accumulation of the residual frost is prevented, and the reliability is improved.

【００３７】また、本実施例では、除霜運転中、復帰制
御手段（５３Ｂ）により、すべての熱源側熱交換器（６
ａ６ｂ）の温度が着霜の融解温度（上記実施例では１
２．５（℃））に達するか、又は吐出冷媒圧力が所定値
（上記実施例では２０（Kg／cm2 ））よりも高くなった
ときに除霜運転を終了して通常運転に復帰するように制
御される。この結果、着霜を確実に融解することができ
る。Further, in this embodiment, during the defrosting operation, all the heat source side heat exchangers (6) are controlled by the return control means (53B).
The temperature of a6b) is the melting temperature of frost (1 in the above embodiment).
2.5 (° C.)) or when the pressure of the discharged refrigerant becomes higher than a predetermined value (20 (Kg / cm 2 ) in the above embodiment), the defrosting operation is terminated and the operation returns to the normal operation. control <br/> is your so. As a result, frost formation can be reliably melted.

【００３８】その上、除霜運転中に各室外電動膨張弁
（８ａ，８ｂ）の開度を全開に制御するものであって
も、周囲の建物の状況等でいずれかの室外ファン（３１
ａ〜３１ｃ）の送風が弱い場合があり、斯かる場合、当
該熱源側熱交換器（６ａ又は６ｂ）における冷媒の凝縮
能力が充分発揮されないので、いずれの熱源側熱交換器
（６ａ，６ｂ）の温度も着霜の融解温度に達するまで除
霜運転を行うと、その間に高圧側圧力の過上昇により高
圧カットを招くことがあるが、上記実施例のように、高
圧の過上昇時には除霜運転を終了することにより、高圧
カットによる異常停止を回避することができる。In addition, even if the outdoor electric expansion valves (8a , 8b) are controlled to fully open during the defrosting operation, any one of the outdoor fans (31
a to 31c) may be weakly blown, and in such a case, the heat source side heat exchanger (6a or 6b) does not sufficiently exhibit the condensation capability of the refrigerant, so that any of the heat source side heat exchangers (6a , 6b). If the defrosting operation is performed until the temperature of the frost also reaches the melting temperature of frost, the high pressure side pressure may rise during the period, causing a high pressure cut. By terminating the operation, an abnormal stop due to the high pressure cut can be avoided.

【００３９】また、逆サイクル除霜運転中にいずれかの
熱源側熱交換器（例えば６ｂ）の温度が着霜の融解温度
１２．５（℃）よりも高くなったときに当該熱源側熱交
換器（６ｂ）の室外電動膨張弁（８ｂ）を絞るのに対し
て、復帰制御手段（５３Ｂ）による通常運転への復帰制
御を行うので、一方で各熱源側熱交換器（６ａ，６ｂ）
の着霜の融解度合いの均一化を図りながら、高圧側圧力
の過上昇を防止しうる利点がある。When the temperature of one of the heat source side heat exchangers (for example, 6b) becomes higher than the frost melting temperature 12.5 (° C.) during the reverse cycle defrosting operation, the heat source side heat exchange is performed. The return control means (53B) controls the return to the normal operation while the outdoor electric expansion valve (8b) of the heat exchanger (6b) is throttled, so that each heat source side heat exchanger (6a , 6b) is controlled.
There is an advantage that it is possible to prevent an excessive rise in the high-pressure side pressure while making the degree of melting of the frost uniform.

【００４０】また、一方の室外電動膨張弁（８ｂ）の絞
りに伴ない熱源側熱交換器（６ｂ）の能力が低減するの
で、吐出冷媒圧力の過上昇が生じやすい条件下にある
が、そのときにも、高圧カットによる異常停止を有効に
防止することができ、著効が得られることになる。Also, since the capacity of the heat source side heat exchanger (6b) is reduced due to the restriction of the one outdoor electric expansion valve (8b), the discharge refrigerant pressure tends to be excessively increased. In some cases, abnormal stop due to high-pressure cut can be effectively prevented, and significant effects can be obtained.

【００４１】なお、上記実施例では、いわゆるヒートポ
ンプ回路を有する空気調和装置の室外ユニット（Ａ）の
ケーシング内に２つの熱源側熱交換器（６ａ，６ｂ）を
配設したいわゆる２面熱交の場合について説明したが、
本発明は斯かる実施例に限定されるものではなく、例え
ば多数の蒸発器を冷媒回路に配設した冷凍機についても
適用しうる。ただし、上記実施例のような２面熱交形の
室外ユニット（Ａ）を有する空気調和装置では、ビルの
屋上に室外ユニット（Ａ）を設置した場合に、周囲の状
況によって一方の熱源側熱交換器への送風が隣接するビ
ルによって遮られる等送風の偏流を生じることが多いの
で、特に本発明による効果が大きい。In the above embodiment, the so-called two-surface heat exchange in which two heat source side heat exchangers (6a , 6b) are disposed in the casing of the outdoor unit (A) of the air conditioner having the so-called heat pump circuit. I explained the case,
The present invention is not limited to such an embodiment, and can be applied to, for example, a refrigerator in which a number of evaporators are arranged in a refrigerant circuit. However, in the air conditioner having the two-sided heat exchange type outdoor unit (A) as in the above embodiment, when the outdoor unit (A) is installed on the roof of a building, one of the heat source side heat sources depends on the surrounding conditions. The air flow to the exchanger is often blocked by an adjacent building, and the air flow often drifts. Therefore, the effect of the present invention is particularly large.

【００４２】[0042]

【発明の効果】以上説明したように、請求項１記載の発
明によれば、逆サイクルに切換え可能に構成された冷媒
回路に蒸発器と電動膨張弁との複数組を互いに並列に接
続してなる冷凍装置の除霜運転制御装置として、冷凍装
置の運転中、除霜運転指令に応じて逆サイクルよる除霜
運転を行うとともに、除霜運転中、いずれかの蒸発器の
温度が融解温度に達すると、当該蒸発器の電動膨張弁の
開度を絞るようにしたので、各蒸発器の着霜の融解度合
いを可及的に均一化することができ、よって、除霜運転
時間の短縮による冷凍装置の運転効率の向上と、残留フ
ロストの低減による信頼性の向上とを図ることができ
る。As described above, according to the first aspect of the present invention, a plurality of sets of an evaporator and an electric expansion valve are connected in parallel to a refrigerant circuit configured to be switchable to a reverse cycle. As a defrosting operation control device for the refrigeration apparatus, while the refrigeration apparatus is operating, the defrosting operation is performed by a reverse cycle in accordance with the defrosting operation command, and during the defrosting operation, the temperature of one of the evaporators becomes the melting temperature. When reached, the degree of opening of the electric expansion valve of the evaporator is reduced, so that the degree of frost melting of each evaporator can be made as uniform as possible, thereby reducing the defrosting operation time. It is possible to improve the operation efficiency of the refrigeration apparatus and improve the reliability by reducing the residual frost.

【００４３】また、すべての蒸発器の温度が着霜の融解
温度に達するか、又は吐出冷媒圧力が所定圧力よりも高
くなったときに、除霜運転を終了して通常運転に復帰す
るようにしたので、各蒸発器の着霜の融解度合いを均一
化できるとともに、各蒸発器の着霜を確実に融解するこ
とができ、且つ高圧側圧力の過上昇による異常停止を回
避することができ、よって、信頼性の顕著な向上を図る
ことができる。When the temperatures of all the evaporators reach the melting temperature of frost or the pressure of the discharged refrigerant becomes higher than a predetermined pressure, the defrosting operation is terminated and the operation returns to the normal operation. As a result, the degree of frost melting of each evaporator can be made uniform, the frost formation of each evaporator can be reliably melted, and abnormal stop due to an excessive rise in the high-pressure side pressure can be avoided. Therefore, the reliability can be significantly improved.

【００４４】また、逆サイクル除霜運転中にいずれかの
蒸発器の温度が着霜の融解温度よりも高くなったときに
当該蒸発器の電動膨張弁を絞るのに対して、復帰制御手
段による通常運転への復帰制御を行うので、一方で各蒸
発器の着霜の融解度合いの均一化を図りながら、高圧側
圧力の過上昇を防止することができる。When the temperature of one of the evaporators becomes higher than the melting temperature of frost during the reverse cycle defrosting operation, the electric expansion valve of the evaporator is throttled. Since the return control to the normal operation is performed, on the other hand, it is possible to prevent an excessive increase in the high-pressure side pressure while making the degree of frost melting of each evaporator uniform.

【００４５】また、一方の電動膨張弁の絞りに伴ない蒸
発器の能力が低減するので、吐出冷媒圧力の過上昇が生
じやすい条件下にあるが、そのときにも、高圧カットに
よる異常停止を有効に防止することができ、著効が得ら
れることになる。In addition, since the capacity of the evaporator is reduced due to the restriction of one of the electric expansion valves, the discharge refrigerant pressure is likely to be excessively increased. This can be effectively prevented, and significant effects can be obtained.

【図面の簡単な説明】[Brief description of the drawings]

【図１】本発明の構成を示すブロック図である。FIG. 1 is a block diagram showing a configuration of the present invention.

【図２】実施例に係る空気調和装置の冷媒配管系統図で
ある。FIG. 2 is a refrigerant piping system diagram of the air-conditioning apparatus according to the embodiment.

【図３】除霜運転中におけるディアイサの代表値決定制
御の内容を示すフローチャート図である。FIG. 3 is a flowchart illustrating the contents of control of determining a representative value of a dicer during a defrosting operation.

【図４】空気調和装置の運転制御の内容を示すフローチ
ャート図である。FIG. 4 is a flowchart showing the contents of operation control of the air conditioner.

【図５】除霜運転中における電動膨張弁の開度制御の内
容を示すフローチャート図である。FIG. 5 is a flowchart showing the content of opening degree control of the electric expansion valve during the defrosting operation.

【符号の説明】[Explanation of symbols]

１ 圧縮機 ６ａ，６ｂ 熱源側熱交換器（蒸発器） ８ａ，８ｂ 室外電動膨張弁 １１ 主冷媒配管 １１ａ，１１ｂ 分岐配管 １４ 主冷媒回路 ５１Ａ 除霜運転制御手段 ５２ 開度低減手段 ５３Ｂ 復帰制御手段 Th21，Th22 ディアイサ（着霜状態検出手段） Ｐ１ 高圧圧力センサ（吐出圧力検出手段） DESCRIPTION OF SYMBOLS 1 Compressor 6a, 6b Heat source side heat exchanger (evaporator) 8a, 8b Outdoor electric expansion valve 11 Main refrigerant pipe 11a, 11b Branch pipe 14 Main refrigerant circuit 51A Defrosting operation control means 52 Opening reduction means 53B Return control means Th21, Th22 Deisa (frost formation detection means) P1 High pressure sensor (discharge pressure detection means)

フロントページの続き (72)発明者 朝妻 洋 大阪府堺市金岡町1304番地 ダイキン工 業株式会社 堺製作所 金岡工場内 (56)参考文献 特開 昭62−17551（ＪＰ，Ａ) 実開 昭57−145958（ＪＰ，Ｕ) 実開 昭55−91459（ＪＰ，Ｕ)Continuation of the front page (72) Inventor Hiroshi Asazuma 1304 Kanaoka-cho, Sakai-shi, Osaka Daikin Industries, Ltd. Sakai Works Kanaoka Factory (56) References JP-A-62-17551 (JP, A) 145958 (JP, U) Actually open 1955-91459 (JP, U)

Claims (1)

(57)【特許請求の範囲】(57) [Claims] 【請求項１】 圧縮機（１）及び凝縮器が接続された主
冷媒配管（１１）に、蒸発器（６ａ）と電動膨張弁（８
ａ）とが直列に接続された蒸発側冷媒配管（１１ａ）を
接続して閉回路に構成すると共に、上記主冷媒配管（１
１）に、蒸発器（６ｂ）と電動膨張弁（８ｂ）とが直列
に接続された１つ以上の分岐配管（１１ｂ）を上記蒸発
側冷媒配管（１１ａ）に対して並列に接続し、かつ冷媒
循環方向が正サイクルと逆サイクルとに切り換わるよう
に構成された冷媒回路（１４）を備えた冷凍装置におい
て、 該冷凍装置の運転中に、除霜運転指令を受けて逆サイク
ルによる除霜運転を行うように制御する除霜運転制御手
段（５１Ａ）と、 上記各蒸発器（６ａ，６ｂ）の温度又は該温度に関連す
る冷媒状態量から蒸発器（６ａ，６ｂ）の着霜状態を個
別に検出する着霜状態検出手段（Th21，Th22）と、 上記圧縮機（１）の吐出冷媒圧力を検出する吐出圧力検
出手段（Ｐ１）と、 上記除霜運転制御手段（５１Ａ）による除霜運転中に、
各着霜状態検出手段（Th21，Th22）の出力を受け、いず
れかの蒸発器（６ａ又は６ｂ）の温度が着霜の融解温度
に達したとき、当該蒸発器（６ａ又は６ｂ）の電動膨張
弁（８ａ又は８ｂ）の開度を絞るように制御する開度低
減手段（５２）と、 上記除霜運転制御手段（５１Ａ）による除霜運転中に、
上記各着霜状態検出手段（Th21，Th22）及び吐出圧力検
出手段（Ｐ１）の出力を受け、すべての蒸発器（６ａ，
６ｂ）の温度が着霜の融解温度に達するか、又は吐出冷
媒圧力が所定値よりも高くなったときに、除霜運転を終
了して通常運転に復帰するように制御する復帰制御手段
（５３Ｂ）とを備えたことを特徴とする冷凍装置の除霜
運転制御装置。An evaporator (6a) and an electric expansion valve (8) are provided in a main refrigerant pipe (11) to which a compressor (1) and a condenser are connected.
a) is connected to the evaporation-side refrigerant pipe (11a) connected in series.
Connected to form a closed circuit and the main refrigerant pipe (1
In 1), the evaporator (6b) and the electric expansion valve (8b) are connected in series.
One or more branch pipes (11b) connected to
Connected in parallel to the side refrigerant pipe (11a), and
The circulation direction switches between forward and reverse cycles
In a refrigeration apparatus including a refrigerant circuit (14) configured to, during operation of the refrigeration system, defrosting operation control means for controlling to perform the defrosting operation by the reverse cycle undergoing defrosting operation command (51A ) and, above the evaporators (6a, 6b) evaporator from the refrigerant state quantity related to the temperature or temperature of the (6a, 6b) frost condition detecting means for detecting individually the frosting condition of (Th21, Th 22) When, the compressor discharge pressure detection means for detecting the discharge refrigerant pressure of (1) (P1), during the defrosting operation by the defrosting operation control means (51A),
When the temperature of any one of the evaporators (6a or 6b) reaches the melting temperature of frost when the output of each frosting state detecting means (Th21 , Th22) is received, the electric expansion of the evaporator (6a or 6b) is performed. the valve opening reducing means controls to narrow the opening of (8a or 8b) (52), during the defrosting operation by the defrosting operation control means (51A),
The evaporator (6a , Th1) receives the output of each of the frosting state detecting means (Th21 , Th22) and the discharge pressure detecting means (P1) .
When the temperature of 6b) reaches the melting temperature of frost formation or when the pressure of the discharged refrigerant becomes higher than a predetermined value , the return control means (53B) controls to end the defrosting operation and return to the normal operation. And a defrosting operation control device for the refrigeration system.
JP3112921A 1991-05-17 1991-05-17 Defrosting operation control device for refrigeration equipment Expired - Fee Related JP2727790B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP3112921A JP2727790B2 (en) 1991-05-17 1991-05-17 Defrosting operation control device for refrigeration equipment

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP3112921A JP2727790B2 (en) 1991-05-17 1991-05-17 Defrosting operation control device for refrigeration equipment

Publications (2)

Publication Number Publication Date
JPH04344085A JPH04344085A (en) 1992-11-30
JP2727790B2 true JP2727790B2 (en) 1998-03-18

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JP3112921A Expired - Fee Related JP2727790B2 (en) 1991-05-17 1991-05-17 Defrosting operation control device for refrigeration equipment

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Families Citing this family (7)

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Publication number Priority date Publication date Assignee Title
JP3341404B2 (en) * 1993-10-29 2002-11-05 ダイキン工業株式会社 Operation control device for air conditioner
JP2007187376A (en) * 2006-01-12 2007-07-26 Sharp Corp Air conditioner
JP4990221B2 (en) * 2008-05-26 2012-08-01 日立アプライアンス株式会社 Air conditioner
JP5310101B2 (en) * 2009-03-03 2013-10-09 ダイキン工業株式会社 Air conditioner
JP2012063033A (en) * 2010-09-14 2012-03-29 Panasonic Corp Air conditioner
WO2021095124A1 (en) * 2019-11-12 2021-05-20 三菱電機株式会社 Refrigeration cycle device
CN115235045B (en) * 2022-07-28 2024-01-16 珠海格力电器股份有限公司 Defrosting control parameter adjustment method and device, computer equipment and storage medium

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5815379B2 (en) * 1979-08-10 1983-03-25 石塚碍子株式会社 Glass bottle with a bottom shape that has excellent internal pressure resistance
JPS6217551A (en) * 1985-07-15 1987-01-26 Mitsubishi Electric Corp Air-conditioning device

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