JPS61256159A - Heat pump type air conditioner - Google Patents

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

【発明の詳細な説明】 産業上の利用分野 本発明は、空気を熱源とするヒ・−トボンブ式空調機に
関するもので、詳しくは低外気時に室外熱交換器に付着
する霜を融解する除霜制御に関するものである。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a heat bomb type air conditioner that uses air as a heat source. It's about control.

従来の技術 従来空気熱源ヒートポンプ式空調機の室外熱交換器の除
霜方式は、大半が四方弁を切換、えて冷房サイクルとし
、室外熱交換器を凝縮器、室内熱交換器を蒸発器とする
逆サイクル除霜方式で、この時コールドドラフト防止の
為に室内ファンを停止していた。Conventional technology Most defrosting systems for outdoor heat exchangers in conventional air source heat pump air conditioners switch four-way valves to create a cooling cycle, with the outdoor heat exchanger serving as a condenser and the indoor heat exchanger serving as an evaporator. It uses a reverse cycle defrosting method, and the indoor fan was stopped at this time to prevent cold drafts.

この方式では基本的に冷媒循環が少なく圧縮機入力の増
大がそれほど期待できないので除霜時間が長くなること
＼並びに除霜運転中の数分間（は室内ファンが停止する
ので暖房感が欠如し快適性が損なわれること＼さらには
除霜運転終了後の四方弁が切換わって暖房運転に復帰し
てからも室内熱交換器の温度が上昇するまでに時間を要
するなど使用者からすれば満足できるものではなかった
。With this method, there is basically little refrigerant circulation and it is not possible to expect much increase in compressor input, so the defrosting time becomes longer, and the indoor fan stops for several minutes during defrosting operation, so there is no feeling of heating and comfort. Users are not satisfied with the fact that it takes time for the temperature of the indoor heat exchanger to rise even after the four-way valve switches and returns to heating operation after the defrosting operation ends. It wasn't something.

近年このような欠点を有する逆サイクル除霜方式に代わ
って、除霜運転時にも四方弁は暖房運転時のままとし、
圧縮機からの吐出ガスの一部を室内熱交換器に流して若
干の暖房能力を維持しながら、吐出ガスの残りを室外熱
交換器の入口に導き除霜を行なうホットガスバイパス除
霜方式が提案されている（例えば「日本冷凍協会講演論
文集」、５５９−１１　、Ｐ５３　）。In recent years, in place of the reverse cycle defrosting system which has these drawbacks, the four-way valve is kept as it is in heating operation even during defrosting operation.
A hot gas bypass defrosting system allows part of the discharged gas from the compressor to flow through the indoor heat exchanger to maintain some heating capacity, while the rest of the discharged gas is guided to the inlet of the outdoor heat exchanger for defrosting. It has been proposed (for example, "Japan Refrigeration Association Lecture Proceedings", 559-11, p. 53).

以下図面を参照しながら上述の従来のヒートポンプ式空
調機の一例について説明する。An example of the above-mentioned conventional heat pump type air conditioner will be described below with reference to the drawings.

第４図は従来のヒートポンプ式空調機の冷凍サイクル図
を示すものである。FIG. 4 shows a refrigeration cycle diagram of a conventional heat pump type air conditioner.

同図において１は容量制御可能な周波数可変圧縮機、２
は四方弁、３け室内熱交換器、４は弁開宴を可変できる
電動膨張弁、５は室外熱交換器、６はホットガスバイパ
ス回路、７は二方弁である。In the figure, 1 is a variable frequency compressor with capacity control;
4 is a four-way valve, a 3-way indoor heat exchanger, 4 is an electric expansion valve whose valve opening can be varied, 5 is an outdoor heat exchanger, 6 is a hot gas bypass circuit, and 7 is a two-way valve.

ホットガスバイパス回路６は、周波数可変圧縮機１の吐
出側と室外熱交換器５の暖房運転時に入口側となる配管
とを連結し、途中に二方弁７を備えて構成されている。The hot gas bypass circuit 6 connects the discharge side of the variable frequency compressor 1 to a pipe that becomes the inlet side during heating operation of the outdoor heat exchanger 5, and includes a two-way valve 7 in the middle.

通常の暖房運転時には二方弁７は閉の状態で暖房サイク
ルを形成するが、低外気時で室外熱交換器５に着霜が生
じ、暖房能力が低下して除霜運転が必要になると、二方
弁７を開いて高温の吐出ガスの大部分をホットガスバイ
パス回路６を経て室外熱交換器５０入口側へ導く。During normal heating operation, the two-way valve 7 is closed to form a heating cycle, but when frost forms on the outdoor heat exchanger 5 when the outside air temperature is low, the heating capacity decreases and a defrosting operation becomes necessary. The two-way valve 7 is opened to guide most of the high temperature discharged gas to the inlet side of the outdoor heat exchanger 50 via the hot gas bypass circuit 6.

同時に高温の吐出ガスの残りを暖房運転時と同様に四方
弁２、室内熱交換器３、電動膨張弁４と流し、若干の暖
房運転を継続して行ない、室外熱交換器５の入口側であ
る点ＣＫで高圧側で分岐した大部分の冷媒と合流させる
。この合流後の冷媒は自身の持つ凝縮熱で室外熱交換器
５を除霜した後、四方弁２を経て周波数可変圧縮機１に
戻り除霜サイクルを完結する。At the same time, the remainder of the high-temperature discharged gas is passed through the four-way valve 2, the indoor heat exchanger 3, and the electric expansion valve 4 in the same way as during heating operation, and a slight heating operation is continued, and the inlet side of the outdoor heat exchanger 5 is At a certain point CK, it joins with most of the refrigerant branched on the high pressure side. After this combined refrigerant defrosts the outdoor heat exchanger 5 with its own condensation heat, it returns to the variable frequency compressor 1 via the four-way valve 2 and completes the defrosting cycle.

発明が解決しようとする問題点 しかしながら上記構成では以下のような問題点があった
。第５図は第４図に示す従来のヒートポンプ式空調機の
除霜運転時におけるサイクルをモリエル線図上に示した
ものである。Problems to be Solved by the Invention However, the above configuration has the following problems. FIG. 5 shows the cycle of the conventional heat pump air conditioner shown in FIG. 4 during defrosting operation on a Mollier diagram.

同図に示す記号ａ　”　ｅは第４図に示したものと対応
する。すなわち除霜運転時に圧縮機吐出側の点ａで分岐
した冷媒は室外熱交換器５の入口側の点Ｃで合流し、こ
の点ＣＩ／′ｉ温度の高い過熱域に存在スル。ここで冷
媒１ｔｉ、−’ｉ−るエンタルピをｐつ。Symbols a and e shown in the same figure correspond to those shown in FIG. However, this point exists in the superheated region where the CI/'i temperature is high.Here, the enthalpy of the refrigerant 1ti and -'i- is p.

そして凝縮後、つまり除霜後の冷媒状態は二相域の液分
の多い点ｄまで変化して圧力損失後の点ｅとなり、この
液分の多い乾き度Ｘ。なる冷媒ヲソのまま周波数可変圧
縮機１に吸入されるので相当の液圧縮を行っていること
になる。これは年間のヒートポンプシーズンの除霜回数
を考慮すると圧縮機信頼性上大きな問題となる。さらに
除霜時の冷媒の利用状況（点Ｃ一点ｄ）からすると、冷
媒の顕然（過熱域）と潜熱（二相域）を利用しており、
霜が融解しドレン水が滴下し始める除霜後期には室外熱
交換器５の表面に温度分布を生じるので、室外熱交換器
５の表面の高温部からは周囲の大気に対流放熱し除霜性
能を落としていることにもなる。After condensation, that is, after defrosting, the state of the refrigerant changes to a point d with a high liquid content in the two-phase region, and reaches a point e after pressure loss, which is the dryness X with a high liquid content. Since the refrigerant is sucked into the variable frequency compressor 1 as it is, a considerable amount of liquid compression is performed. This poses a major problem in terms of compressor reliability, considering the number of defrosting operations during the annual heat pump season. Furthermore, from the usage status of refrigerant during defrosting (points C and d), the manifest (superheat region) and latent heat (two-phase region) of the refrigerant are used.
In the later stages of defrosting when the frost melts and drain water begins to drip, a temperature distribution occurs on the surface of the outdoor heat exchanger 5, so heat is convectively radiated from the high temperature portion of the surface of the outdoor heat exchanger 5 to the surrounding atmosphere to defrost. This will also reduce performance.

また第６図は前記従来のヒートポンプ式空調機の除霜運
転時の暖房能力の変化を示し、第７図は同じく除霜運転
時の高圧側圧力と低圧側圧力の変化を示す。第７図にお
いてＡは高圧側圧力、Ｂは低圧側圧力を示す。Further, FIG. 6 shows the change in the heating capacity of the conventional heat pump type air conditioner during defrosting operation, and FIG. 7 similarly shows the change in high pressure side pressure and low pressure side pressure during defrosting operation. In FIG. 7, A indicates the high pressure side pressure, and B indicates the low pressure side pressure.

同図より明らかなように除霜が進むにつれて高圧側圧力
Ａと低圧側圧力Ｂの比、すなわち圧縮比が小さくなり、
また低圧側圧力Ｂは上昇するので前記周波数可変圧縮機
１の吸入側の冷媒の比容積が小さくなって冷凍ブイクル
内の冷媒の循環量は増加し、したがって暖房能力は除霜
開始時一旦大きく低下した後徐々に増加する。このため
除霜開始時、暖房能力が大きく低下して居住者に不快感
を与える恐れがあり、逆に除霜終了時近くになると暖房
能力は除霜開始時に比べて大きくなりすぎ、それだけ除
霜時間が長くなっていた。As is clear from the figure, as defrosting progresses, the ratio of high-pressure side pressure A to low-pressure side pressure B, that is, the compression ratio, decreases.
Furthermore, since the low-pressure side pressure B increases, the specific volume of the refrigerant on the suction side of the variable frequency compressor 1 decreases, and the amount of refrigerant circulated within the refrigeration buoy increases.Therefore, the heating capacity temporarily decreases significantly at the start of defrosting. After that, it gradually increases. For this reason, when defrosting begins, the heating capacity may drop significantly, causing discomfort to the occupants, and conversely, near the end of defrosting, the heating capacity becomes too large compared to when defrosting begins, and the defrosting increases. Time was getting longer.

本発明は上記問題点に鑑み、除霜運転時にも室内熱交換
器に高温の吐出ガスの一部を流して暖房運転継続可能と
して、圧縮機への多量の液戻りや液圧縮を軽減し、室外
熱交換器表面の温度分布を改善して一様温度とする均一
除霜を実現し、さらに室内熱交換器を流れる冷媒流量と
バイパス回路を流れる冷媒流量の割合を可変として、長
期にわたって信頼性の高い、しかも居住者に不快感を与
えることなく除霜効率を改善したヒートポンプ式空調機
を提供するものである。In view of the above-mentioned problems, the present invention allows a portion of the high temperature discharged gas to flow through the indoor heat exchanger during defrosting operation to allow continued heating operation, thereby reducing a large amount of liquid returning to the compressor and liquid compression. By improving the temperature distribution on the surface of the outdoor heat exchanger and achieving uniform defrosting with a uniform temperature, the ratio of the refrigerant flow rate flowing through the indoor heat exchanger and the refrigerant flow rate flowing through the bypass circuit is variable, ensuring long-term reliability. To provide a heat pump type air conditioner with high defrosting efficiency and improved defrosting efficiency without causing discomfort to residents.

間預点を解決するだめの手段 上記問題点を解決するために本発明のヒートポンプ式空
調機は、圧縮機、四方弁、室内熱交換器、絞り量を可変
とした第１の絞り装置、室外熱交換器等を順次環状に配
管で連結して冷凍サイクルを構成し、暖房運転時に高圧
となる前記圧縮機より前記室内熱交換器に至る配管と、
同じく暖房運転時に低圧となる前記室外熱交換器より圧
縮機に至る配管とを結ぶバイパス回路を設け、前記バイ
パス回路に絞り量を可変とし、かつ流路を遮断可能とし
た第２の絞り装置を設け、前記室外熱交換器の除霜運転
開始時には前記第１の絞り装置の絞り量を暖房運転時の
絞り量よりも小さくし、さらに除霜運転中には前記第２
の絞り装置の絞り量を変化させて前記室内熱交換器を流
ね、る冷媒流量と前記バイパス回路を流れる冷媒流量の
割合を可変として暖房運転継続可能としたものである。Means for Solving Interstitial Points In order to solve the above problems, the heat pump type air conditioner of the present invention includes a compressor, a four-way valve, an indoor heat exchanger, a first throttling device with a variable throttling amount, and an outdoor throttling device. A refrigeration cycle is constructed by sequentially connecting heat exchangers and the like in a ring with piping, and piping reaches from the compressor to the indoor heat exchanger, which is at high pressure during heating operation;
Similarly, a bypass circuit is provided that connects the pipe from the outdoor heat exchanger to the compressor, which has a low pressure during heating operation, and a second throttling device is provided in the bypass circuit with a variable throttling amount and capable of blocking the flow path. The throttling amount of the first throttling device is made smaller than the throttling amount during the heating operation when the defrosting operation of the outdoor heat exchanger starts, and the throttling amount of the first throttling device is made smaller than the throttling amount during the heating operation.
By changing the throttle amount of the throttle device, the ratio between the flow rate of refrigerant flowing through the indoor heat exchanger and the flow rate of refrigerant flowing through the bypass circuit is made variable, thereby making it possible to continue the heating operation.

作　　用 木発Ｆ３Ａは上記構成（てより、除霜運転時にも高温の
吐出ガスの一部を室内熱交換器に流して暖房運転継続可
能とし、第１の絞り装置の絞りを小さくして、高温の吐
出ガスの残りを室外熱交換器出口である圧縮機吸入側へ
直接戻すので、冷媒循環もよく圧縮機入靜コ持した状態
で、圧縮機吸入冷媒も二相ではあるが乾き度を大きくで
き、液戻りや液圧縮を軽減できる。また室外熱交換器へ
の流入冷媒も二相となり、除霜初期、中期はもちろん融
解後のドレン水滴下中の後期から乾燥期まで室外熱交換
器表面は温度ムラなく一様に温度上昇するので、暖房運
転例戻る復帰温度までに一部分がどんどん温度上昇する
ことがなくなり、それだけ周囲への対流放熱損失が押え
られて除霜効率も改善できる。さらに、室内熱交換器を
流れる冷媒流量とバイパス回路を流れる冷媒流量の割合
を可変としたことで、除霜時居住者に不快感を与えるこ
となくまた暖房能力の極端な上昇を招かず、除霜効率を
さらに改善できる。Operation The wood generator F3A has the above-mentioned configuration (by which, even during defrosting operation, a part of the high temperature discharged gas is allowed to flow through the indoor heat exchanger to enable continued heating operation, and the diaphragm of the first diaphragm device is made small, The remainder of the high-temperature discharged gas is returned directly to the outdoor heat exchanger outlet, which is the compressor suction side, so the refrigerant circulation is good and the compressor remains quiet, and the compressor suction refrigerant is also two-phase, but the dryness is maintained. The refrigerant flowing into the outdoor heat exchanger becomes two-phase, so the outdoor heat exchanger can be used not only in the early and middle stages of defrosting, but also in the late stages during dripping of drain water after melting and during the drying period. Since the temperature of the surface rises uniformly and evenly, the temperature of one part does not rise rapidly until the temperature returns to the normal state during heating operation, and convective heat radiation loss to the surroundings is suppressed to the extent that the defrosting efficiency can be improved. By making the ratio of the refrigerant flow rate flowing through the indoor heat exchanger and the refrigerant flow rate flowing through the bypass circuit variable, defrosting can be performed without causing discomfort to residents or causing an extreme increase in heating capacity. Efficiency can be further improved.

実施例 以下本発明の一実施例のヒートポンプ式空調機について
、図面を参照しながら説明する。EXAMPLE Hereinafter, a heat pump type air conditioner according to an example of the present invention will be described with reference to the drawings.

第１図は本発明の一実施例におけるヒートポンプ式空調
機の冷凍ヴイクル図を示すものである。FIG. 1 shows a refrigeration vehicle diagram of a heat pump air conditioner according to an embodiment of the present invention.

同図において、１１は圧縮機、１２は四方弁、１３は室
内熱交換器、１４は電磁力で弁開宴を可変できる第１電
動膨張弁、１５け室外熱交換器、１６はバイパス回路、
１７はバイパス回路に設けられて電磁力で弁開度を可変
できる第２電動膨張弁である。また１８は室内熱交換器
１３の温度を検知する室内温度検出素子、１９は室外熱
交換器１５の温度を検知する室外温度検出素子であり、
２０はこの室内温度検出素子１８、室外温度検出素子１
９の温度信号を受けて第１電動膨張弁１４、第２電動膨
張弁１７の弁開度を制御する制御回路である。そして圧
縮機１１、四方弁１２、室内熱交換器１３、第１電動膨
張弁１４、室外熱交換器１５を順次環状に連結し、さら
に圧縮機１１の吐出側と、室外熱交換器１５の暖房運転
時の出口側とを結び、その途中に第２電動膨張弁１７を
備えたバイパス回路１６を設けたものである。In the figure, 11 is a compressor, 12 is a four-way valve, 13 is an indoor heat exchanger, 14 is a first electric expansion valve whose valve opening can be varied by electromagnetic force, 15 is an outdoor heat exchanger, 16 is a bypass circuit,
A second electric expansion valve 17 is provided in the bypass circuit and whose opening degree can be varied by electromagnetic force. Further, 18 is an indoor temperature detection element that detects the temperature of the indoor heat exchanger 13, and 19 is an outdoor temperature detection element that detects the temperature of the outdoor heat exchanger 15.
20 denotes this indoor temperature detection element 18 and outdoor temperature detection element 1.
This is a control circuit that receives the temperature signal No. 9 and controls the valve opening degrees of the first electric expansion valve 14 and the second electric expansion valve 17. The compressor 11, the four-way valve 12, the indoor heat exchanger 13, the first electric expansion valve 14, and the outdoor heat exchanger 15 are sequentially connected in an annular manner, and the discharge side of the compressor 11 and the outdoor heat exchanger 15 are used for heating. A bypass circuit 16 is connected to the outlet side during operation, and a bypass circuit 16 including a second electric expansion valve 17 is provided in the middle.

次に、以上のように構成されたヒートポンプ式空調機に
ついてその動作を説明する。通常の暖房運転時には第２
電動膨張弁１７は全閉の状態となっており、冷媒は圧縮
機１１、四方弁１２、室内熱交換器１３、第１電動膨張
弁１４、室外熱交換器１５、四方弁１２と流れて圧縮機
１１に戻り暖房サイクルを形成し、バイパス回路１６に
は冷媒は流れない。Next, the operation of the heat pump air conditioner configured as described above will be explained. During normal heating operation, the second
The electric expansion valve 17 is in a fully closed state, and the refrigerant flows through the compressor 11, the four-way valve 12, the indoor heat exchanger 13, the first electric expansion valve 14, the outdoor heat exchanger 15, and the four-way valve 12, and is compressed. The refrigerant returns to the machine 11 to form a heating cycle, and no refrigerant flows through the bypass circuit 16.

ところが、低外気温時には室外熱交換器１５に着霜が生
じ、室外温度検出素子１９の温度信号が設定値まで下が
ると制御回路２０が除霜開始指令を発し、四方弁１２は
その捷まの状態で第２電動膨張弁を居住者が不快感を感
じない程度の暖房能力の低下となるように設定した所定
の弁開度まで開き、高温の吐出ガスを点ａ′で分岐させ
、一部ばそのまま室内熱交換器１３へ流し、残りは室外
熱交換器１５の出口側へ導くとともに、第１電動膨張弁
１４の弁開度を全開気味にすることで絞り量をほぼゼロ
として除霜を開始する。However, when the outside temperature is low, frost forms on the outdoor heat exchanger 15, and when the temperature signal of the outdoor temperature detection element 19 drops to the set value, the control circuit 20 issues a command to start defrosting, and the four-way valve 12 stops the defrosting. In this state, the second electric expansion valve is opened to a predetermined valve opening that is set to reduce the heating capacity to the extent that the occupants do not feel discomfort, and the high-temperature discharged gas is branched at point a'. The remaining part flows directly to the indoor heat exchanger 13, and the rest is guided to the outlet side of the outdoor heat exchanger 15. At the same time, the first electric expansion valve 14 is slightly opened fully to reduce the throttling amount to almost zero and defrost. Start.

第２図は第１図に示すヒートポンプ式空調機の一実施例
の除霜運転時におけるブイクルをモリエル線図に示した
ものである。FIG. 2 is a Mollier diagram showing the vehicle during defrosting operation of one embodiment of the heat pump type air conditioner shown in FIG.

同図に示す記号ａ′〜ｅ′は第１図に示したものと対応
する。すなわち除霜運転時に点ａ′からそのまま室内熱
交換器１３へ流した高温の吐出ガスは、第１電動膨張弁
１４の弁開度が全開気味になっているので比較的低い温
度約３０〜４０°Ｃで凝縮放熱し、点ｂ′に移り図示し
ない室内ファンのＯＮにより暖房運転継続可能となる。Symbols a' to e' shown in the figure correspond to those shown in FIG. That is, during the defrosting operation, the high-temperature discharge gas that flows directly from point a' to the indoor heat exchanger 13 has a relatively low temperature of about 30 to 40℃ because the first electric expansion valve 14 is fully opened. The temperature is condensed at .degree. C. and the heat is dissipated, and then the temperature moves to point b' and heating operation can be continued by turning on the indoor fan (not shown).

途中の配管や第１電動膨張弁１４の若干の絞りで減圧し
て点Ｃ′となり室外熱交換器１５に流入して、さらに霜
の融解６乙ノ 温度である約０℃で凝縮放熱して除霜し点くに至る。こ
の時の除霜に利用する冷媒のエンタルピ差はΔｉｄｅ　
ｆ＝ｉｃ’　　ｉｄ’　トなり、室外熱交換器１５への
流入冷媒状態は点Ｃ′に示すように既に二相となってい
る。ちなみに室内暖房に利用する冷媒のエンタルピ差は
途中の熱ロスを無視すればｉａ′−ｉｂ’となる。The pressure is reduced through the pipes along the way and a slight restriction in the first electric expansion valve 14, and it reaches point C' and flows into the outdoor heat exchanger 15, where it condenses and radiates heat at approximately 0°C, which is the temperature at which frost melts. Defrost and turn on. The enthalpy difference of the refrigerant used for defrosting at this time is Δide
f=ic'id', and the state of the refrigerant flowing into the outdoor heat exchanger 15 is already two-phase as shown at point C'. Incidentally, the enthalpy difference of the refrigerant used for indoor heating is ia'-ib' if heat loss during the heating is ignored.

一方残りの温度の吐出ガスは室外熱交換器１５の出口側
に導かれるのではソ等エンタルピ変化後、主回路を流れ
てきた液分の多い冷媒と合流し混合して点ｅ′となり、
圧縮機１１に吸入される。この点ｅ′は二相状態にある
ものの冷媒乾き度Ｘｅ′が大きく液分が少ないので液戻
りや液圧縮を軽減まだは実質的に回避することができる
。さらにまた除霜運転時に室外熱交換器１５へ流入して
いる冷媒は基本的に二相状態であるため冷媒温度つまり
室外熱交換器１５の表面温度も一定となり、同表面温度
にムラがないため均一除霜が実現できる。On the other hand, the discharged gas at the remaining temperature is led to the outlet side of the outdoor heat exchanger 15, and after changing its enthalpy, it joins and mixes with the liquid-rich refrigerant that has flowed through the main circuit and reaches point e'.
It is sucked into the compressor 11. At this point e', although the refrigerant is in a two-phase state, the dryness of the refrigerant Xe' is large and the liquid content is small, so liquid return and liquid compression can be reduced or substantially avoided. Furthermore, since the refrigerant flowing into the outdoor heat exchanger 15 during defrosting operation is basically in a two-phase state, the refrigerant temperature, that is, the surface temperature of the outdoor heat exchanger 15, is also constant, and there is no unevenness in the surface temperature. Uniform defrosting can be achieved.

また、除霜運転開始時、第２電動膨張弁１７の弁開度を
全開とせずに所定の弁開度とすることで高圧側圧力の低
下が少なく、シたがって暖房能力が急激に低下すること
がなく居住者に不快感を与えない。さらに、除霜が進行
するにつれ、従来例で示したのと同様に次第に高圧側圧
力が高くなって暖房能力が大きくなるが、室内温度検出
素子１８の温度信号が設定値まで上昇すると制御回路２
０が信号を発して第２電動膨張弁１７の弁開度を大きく
し、それにより高圧側圧力、暖房能力の増加を押さえ、
バイパス回路１６を流れる冷媒流量を増加させることが
できるのでさらに除霜効率の改善が可能となる。Furthermore, when the defrosting operation is started, by setting the valve opening of the second electric expansion valve 17 to a predetermined valve opening rather than fully opening, the drop in high pressure side pressure is small, and therefore the heating capacity is sharply reduced. without causing any discomfort to residents. Furthermore, as defrosting progresses, the high-pressure side pressure gradually increases and the heating capacity increases, as shown in the conventional example, but when the temperature signal from the indoor temperature detection element 18 rises to the set value, the control circuit 2
0 issues a signal to increase the valve opening of the second electric expansion valve 17, thereby suppressing the increase in high pressure side pressure and heating capacity,
Since the flow rate of refrigerant flowing through the bypass circuit 16 can be increased, defrosting efficiency can be further improved.

第３図の実線は、本発明の一実施例におけるヒートポン
プ式空調機の除霜運転時の暖房能力の変化を示すもので
、前記のように第２電動膨張弁１７の弁開度を変化させ
ることで、破線で示す従来例のヒートポンプ式空調機の
除霜時の暖房能力の変化と比較して除霜開始時に居住者
に不快感を与えることなく、除霜終了時近くで不必要な
暖房を行なうこともない。The solid line in FIG. 3 shows the change in the heating capacity during the defrosting operation of the heat pump air conditioner in one embodiment of the present invention, and the valve opening degree of the second electric expansion valve 17 is changed as described above. As a result, compared to the change in heating capacity during defrosting of a conventional heat pump type air conditioner shown by the broken line, this eliminates unnecessary heating near the end of defrosting without causing discomfort to residents at the start of defrosting. I don't even do it.

なお、本発明は第１、第２の絞り装置の最良の形態とし
て電磁力を駆動源として弁開度を可変とした第１、第２
の電動膨張弁１４．１７を用いて説明したが、それぞれ
の絞り装置をキャピラリ等の絞りを複数個用いて構成し
、適宜切換により制御してもよく、さらに弁開度を可変
する手段としてバイメタル若しくは形状記憶合金等を用
いてもよい。また、暖房能力の増加を室内熱交換器１３
の温度を用いて検知したが、本発明はそれに限定される
ものではなく、暖房能力の増加を検知できるものであれ
ば、検出する圧力、温度等の位置およびその手段は任意
である。また、除霜開始時期の決定についても同様であ
る。The present invention provides the best mode of the first and second throttle devices in which the valve opening degree is variable using electromagnetic force as a driving source.
Although the description has been made using electric expansion valves 14 and 17 of Alternatively, a shape memory alloy or the like may be used. In addition, increasing heating capacity can be achieved by using indoor heat exchanger 13.
Although the present invention is not limited to this, the position of the pressure, temperature, etc. to be detected and the means thereof are arbitrary as long as an increase in heating capacity can be detected. The same applies to the determination of the time to start defrosting.

発明の効果 以上のように本発明のヒートポンプ式空調機は、圧縮機
、四方弁、室内熱交換器、絞り量を可変とした第１の絞
り装置、室外熱交換器等を順次環状に配管で連結して冷
凍サイクルを構成し、暖房運転時に高圧となる前記圧縮
機より前記室内熱交換バイパス回路を形成し、前記バイ
パス回路に絞り量を可変とし、かつ流路を遮断可能とし
た第２の絞り装置を設け、前記室外熱交換器の除霜運転
開始時には前記第１の絞り装置の絞り量を暖房運転時の
絞り量よりも小さくし、除霜運転中には前記第２の絞り
装置の絞り量を変化させて前記室内熱交換器を流れる冷
媒流量と前記バイパス回路を流れる冷媒流量の割合を可
変として暖房運転継続可能としたもので、除霜運転時に
も室内熱交換器に高温の吐出ガスの一部を流して暖房運
転継続可能として、圧縮機への多量の液戻りや液王縮を
軽減し、室外熱交換器表面の温度分布を改善して一様温
度とする均一除霜を実現し、さらに室内熱交換器を流れ
る冷媒流量とバイパス回路を流れる冷媒流量の割合を可
変として、長期にわたって信頼性が高く、シかも居住者
に不快感を与えることなく除Ｍ効率を改善できる等の種
々の効果全有する。Effects of the Invention As described above, the heat pump type air conditioner of the present invention has a compressor, a four-way valve, an indoor heat exchanger, a first throttling device with a variable throttling amount, an outdoor heat exchanger, etc., which are connected in order in an annular pipe. A second compressor is connected to form a refrigeration cycle, and the indoor heat exchange bypass circuit is formed from the compressor which is at high pressure during heating operation, and the bypass circuit has a variable throttling amount and can shut off the flow path. A throttling device is provided, and when the outdoor heat exchanger starts defrosting operation, the throttling amount of the first throttling device is made smaller than the throttling amount during heating operation, and during the defrosting operation, the throttling amount of the second throttling device is set to be smaller than the throttling amount during the heating operation. By changing the throttle amount, the ratio of the refrigerant flow rate flowing through the indoor heat exchanger and the refrigerant flow rate flowing through the bypass circuit can be varied to enable continued heating operation, and even during defrosting operation, high-temperature discharge is discharged to the indoor heat exchanger. By allowing a portion of the gas to flow through to continue heating operation, it reduces a large amount of liquid returning to the compressor and liquid regurgitation, and improves the temperature distribution on the surface of the outdoor heat exchanger to achieve uniform defrosting. Furthermore, by making the ratio of the refrigerant flow rate flowing through the indoor heat exchanger and the refrigerant flow rate flowing through the bypass circuit variable, it is possible to improve M removal efficiency with high reliability over a long period of time and without causing discomfort to residents. It has all kinds of effects.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は本発明の一実施例におけるヒートポンプ式空調
機の冷凍サイクル図、第２図は同ヒートポンプ式空調機
の除霜運転時のブイタルをモリエル線図上にあられした
図、第３図は同ヒートポンプ式空調機の除霜運転時の暖
房能力の変化を示す≧−図、第４図は従来のヒートポン
プ式空調機の冷凍サイクル図、第５図は第４図に示す従
来のと−トポング式空調機の除霜運転時のす、イクルを
モＩＪ　１−ル線図上にあられした図、第６図は同じ〈
従来のトーーーＦポンプ式空調機の除霜運転時の暖房能
力の変化を示す説明図、第７図は同じ〈従来のと・−ト
ポンプ式空調機の除霜運転時の高圧側圧力と低圧側圧力
の変化を示す説明図である、１１・・・・・・圧縮機、
１２・・・・・・四方弁、１３・・・・・・室内熱交換
器、１４・・・・・・第１電動膨張弁（第１の絞り装置
）、１５・・・・・・室外熱交換器、１６・・・・・・
バイパス回路、１７・・・・・・第２電動膨張弁（第２
の絞り装置）。 代理人の氏名　弁理士　中　尾　敏　男　ほか１名１１
−Ｌ補機 ７２−−一口方介 ／３−一一室内番輝爽益 第　、　　図　　　　　　　　　　　　　１４−−一部
１襄動府多う駐性Ｃ第ｒの絞服乾工）だ−一一室外一欠
侠各 ／６〜−−パイハ′人回玲 １７−ＭＺ電動乃μ〃し升（第２の松、りＡｌ）第２図 乙ｔと′Ｃｔノ ｌ。 第３図 −一村間 ｌ　−一用Ｊ（（可変り揚機 ？−田方行 ３−１円−丸侠器 第４図　　　　　　　４−を動屡震升 ５−−−室？ｌ−熊欠侠呑 ６−一一木ットｒ入へイバ入国期１ 第５図 第６図 所間 第７図 所間Fig. 1 is a refrigeration cycle diagram of a heat pump air conditioner according to an embodiment of the present invention, Fig. 2 is a diagram showing the buital during defrosting operation of the heat pump air conditioner on a Mollier diagram, and Fig. 3 is a diagram of the refrigeration cycle of a heat pump air conditioner according to an embodiment of the present invention. Figure 4 shows the change in heating capacity during defrosting operation of the heat pump air conditioner, Figure 4 is a refrigeration cycle diagram of the conventional heat pump air conditioner, and Figure 5 is the conventional heat pump air conditioner shown in Figure 4. Figure 6 is a diagram showing the cycle during defrosting operation of a type air conditioner on a mole diagram.
Figure 7 is an explanatory diagram showing the change in heating capacity during defrosting operation of a conventional To-F pump type air conditioner. 11... Compressor, which is an explanatory diagram showing changes in pressure.
12...Four-way valve, 13...Indoor heat exchanger, 14...First electric expansion valve (first throttling device), 15...Outdoor Heat exchanger, 16...
Bypass circuit, 17... Second electric expansion valve (second
squeezing device). Name of agent: Patent attorney Toshio Nakao and 1 other person11
-L auxiliary machine 72--Instruction/3-11 Indoor No. Teru Souichi, Figure 14--Part 1 (Part 1) Ikkashikyo each/6~--Paiha'jin Kairei 17-MZ electric no μ〃shi box (second pine, riAl) Figure 2 Ot and 'Ct nol. Figure 3 - One village l - One use J ((Variable lift machine? - Tagata line 3 - 1 yen - Marukyo equipment Figure 4 Kyoto 6-11 Kito r Iba entry period 1 Fig. 5 Fig. 6 Between the offices Fig. 7 Between the offices

Claims (2)

【特許請求の範囲】[Claims] （１）圧縮機、四方弁、室内熱交換器、絞り量を可変と
した第１の絞り装置、室外熱交換器等を順次環状に配管
で連結して冷凍サイクルを構成し、暖房運転時に高圧と
なる前記圧縮機より前記室内熱交換器に至る配管と、暖
房運転時に低圧となる前記室外熱交換器より圧縮機に至
る配管とを結ぶバイパス回路を形成し、前記バイパス回
路に絞り量を可変とし、かつ流路を遮断可能とした第２
の絞り装置を設け、前記室外熱交換器の除霜運転開始時
には前記第１の絞り装置の絞り量を暖房運転時の絞り量
よりも小さくし、除霜運転中には前記第２の絞り装置の
絞り量を変化させて前記室内熱交換器を流れる冷媒流量
と前記バイパス回路を流れる冷媒流量の割合を可変とし
て暖房運転継続可能としたヒートポンプ式空調機。(1) A compressor, a four-way valve, an indoor heat exchanger, a first throttling device with a variable throttling amount, an outdoor heat exchanger, etc. are sequentially connected in a ring with piping to form a refrigeration cycle, and the high pressure during heating operation is A bypass circuit is formed that connects piping from the compressor to the indoor heat exchanger, which becomes low pressure during heating operation, and piping from the outdoor heat exchanger to the compressor, which becomes low pressure during heating operation, and the amount of throttling is variable in the bypass circuit. The second
A throttling device is provided, and when the defrosting operation of the outdoor heat exchanger starts, the throttling amount of the first throttling device is made smaller than the throttling amount during the heating operation, and during the defrosting operation, the throttling amount of the first throttling device is set to be smaller than the throttling amount during the heating operation. A heat pump type air conditioner capable of continuing heating operation by changing the amount of throttle of the air conditioner to vary the ratio of the flow rate of refrigerant flowing through the indoor heat exchanger and the flow rate of refrigerant flowing through the bypass circuit. （２）除霜運転時、暖房能力が設定値以上になると前記
第２の絞り装置の絞り量を小さくする特許請求の範囲第
１項記載のヒートポンプ式空調機。(2) The heat pump air conditioner according to claim 1, wherein during defrosting operation, when the heating capacity exceeds a set value, the throttling amount of the second throttling device is reduced.