JP2765391B2 - Oil recovery operation control device for air conditioner - Google Patents
Oil recovery operation control device for air conditionerInfo
- Publication number
- JP2765391B2 JP2765391B2 JP22754492A JP22754492A JP2765391B2 JP 2765391 B2 JP2765391 B2 JP 2765391B2 JP 22754492 A JP22754492 A JP 22754492A JP 22754492 A JP22754492 A JP 22754492A JP 2765391 B2 JP2765391 B2 JP 2765391B2
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- Prior art keywords
- oil recovery
- temperature
- signal
- recovery operation
- low
- Prior art date
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- Air Conditioning Control Device (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、空気調和装置の油回収
運転制御装置に関し、特に、冷房運転の油回収時におけ
る高圧圧力の制御対策に係るものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil recovery operation control device for an air conditioner, and more particularly to a measure for controlling high pressure during oil recovery in a cooling operation.
【０００２】[0002]
【従来の技術】従来より、空気調和装置には、特開昭６
３−７３０５２号公報に開示されているように、インバ
ータにより容量制御される圧縮機と、四路切換弁と、室
外熱交換器と、室外電動膨脹弁とが順に接続された室外
ユニットに対して、室外電動膨脹弁と室内熱交換器とが
接続された室内ユニットが並列に接続されているものが
る。そして、空調運転時間を積算し、その積算時間が一
定時間になると、上記圧縮機を大容量にし、各電動膨脹
弁をを大開度にすると共に、室外ファンを駆動して油回
収運転を行うようにしている。この油回収運転により潤
滑油を圧縮機に戻して該圧縮機の焼付け等を防止するよ
うにしている。2. Description of the Related Art Conventionally, air conditioners have been disclosed in
As disclosed in Japanese Patent Application Publication No. 3-73052, an outdoor unit in which a compressor whose capacity is controlled by an inverter, a four-way switching valve, an outdoor heat exchanger, and an outdoor electric expansion valve are sequentially connected. Some indoor units in which an outdoor electric expansion valve and an indoor heat exchanger are connected are connected in parallel. Then, the air-conditioning operation time is integrated, and when the integrated time reaches a certain time, the compressor is increased in capacity, each electric expansion valve is set to a large opening degree, and the outdoor fan is driven to perform the oil recovery operation. I have to. By this oil recovery operation, the lubricating oil is returned to the compressor to prevent seizure or the like of the compressor.
【０００３】[0003]
【発明が解決しようとする課題】上述した空気調和装置
において、油回収運転を行う際、圧縮機の容量を増大し
て冷媒循環量を多くするようにしているため、低外気温
の冷房運転時にオイルフォーミング等が生ずるという問
題があった。つまり、この低外気温の冷房運転時におい
ては、高圧圧力が低く、これに伴って低圧圧力も低下し
ているため、この状態で圧縮機の容量を増大すると、更
に、低圧圧力が低下することになり、オイルフォーミン
グ等が生じ、圧縮機内の潤滑油が不足するという問題あ
った。また、上記油回収時に圧縮機の容量を増大するの
で、快適な室温制御を行うことができないという問題が
あった。In the above-described air conditioner, when performing the oil recovery operation, the capacity of the compressor is increased to increase the refrigerant circulation amount. There is a problem that oil forming or the like occurs. In other words, during the cooling operation at the low outside air temperature, the high pressure is low, and the low pressure is also reduced. Accordingly, if the capacity of the compressor is increased in this state, the low pressure is further reduced. , Oil forming and the like occur, and there is a problem that the lubricating oil in the compressor runs short. In addition, since the capacity of the compressor is increased at the time of oil recovery, there is a problem that comfortable room temperature control cannot be performed.
【０００４】本発明は、斯かる点に鑑みてなされたもの
で、油回収運転時にオイルフォーミング等が生ずること
なく、快適な室温制御を行うようにするものである。[0004] The present invention has been made in view of such a point, and is intended to perform comfortable room temperature control without causing oil forming or the like during an oil recovery operation.
【０００５】[0005]
【課題を解決するための手段】上記の目的を達成するた
めに、本発明が講じた手段は、油回収運転時に熱源側フ
ァンを停止するようにしたものである。Means for Solving the Problems In order to achieve the above object, the means taken by the present invention is to stop the heat source side fan during the oil recovery operation.
【０００６】具体的に、図１に示すように、請求項１に
係る発明が講じた手段は、先ず、圧縮機(1) と、熱源側
ファン(3b)が付設された熱源側熱交換器(3) と、膨脹機
構(5) と、利用側熱交換器(6) とが順に接続されてなる
冷媒回路(9) を備えた空気調和装置を前提としている。More specifically, as shown in FIG. 1, the means according to the first aspect of the present invention comprises a compressor (1) and a heat source side heat exchanger provided with a heat source side fan (3b). It is assumed that the air conditioner includes a refrigerant circuit (9) in which (3), an expansion mechanism (5), and a use side heat exchanger (6) are sequentially connected.
【０００７】そして、冷房運転時における凝縮圧力相当
飽和温度を検出する飽和温度検出手段(Thc) が設けられ
ている。更に、該飽和温度検出手段(Thc) の温度信号を
受けて、冷房運転時における凝縮圧力相当飽和温度が予
め設定された低温度になると低温信号を出力する低温判
別手段(13)と、該低温判別手段(13)が所定時間継続して
低温信号を出力すると油回収信号を出力して油回収運転
を実行する油回収実行手段(14)とが設けれられている。
加えて、該油回収実行手段(14)が油回収信号を出力する
と上記熱源側ファン(3b)を停止するファン停止手段(15)
と、上記油回収実行手段(14)が油回収運転を開始した
後、所定状態になると該油回収実行手段(14)の油回収運
転を終了させると共に、ファン停止手段(15)の停止制御
を終了させる復帰信号を出力する冷房復帰手段(17)とが
設けられた構成としている。[0007] Saturation temperature detecting means (Thc) for detecting a saturation temperature corresponding to the condensing pressure during the cooling operation is provided. A low-temperature discriminating means (13) for receiving a temperature signal from the saturation temperature detecting means (Thc) and outputting a low-temperature signal when the condensing pressure-equivalent saturation temperature during cooling operation becomes a preset low temperature; An oil recovery executing means (14) for outputting an oil recovery signal when the determination means (13) continuously outputs a low temperature signal for a predetermined time and executing an oil recovery operation is provided.
In addition, fan stop means (15) for stopping the heat source side fan (3b) when the oil recovery execution means (14) outputs an oil recovery signal.
After the oil recovery execution unit (14) starts the oil recovery operation, when the oil recovery execution unit (14) enters a predetermined state, the oil recovery execution unit (14) terminates the oil recovery operation and controls the stop of the fan stop unit (15). A cooling return means (17) for outputting a return signal for terminating the cooling operation is provided.
【０００８】また、図２に示すように、請求項２に係る
発明が講じた手段は、先ず、圧縮機(1) と、風量可変の
熱源側ファン(3b)が付設された熱源側熱交換器(3) と、
膨脹機構(5) と、利用側熱交換器(6) とが順に接続され
てなる冷媒回路(9) を備えた空気調和装置を前提として
いる。As shown in FIG. 2, the means according to the second aspect of the present invention includes a compressor (1) and a heat source-side heat exchange fan provided with a heat source-side fan (3b) having a variable air volume. Vessel (3),
It is assumed that the air conditioner includes a refrigerant circuit (9) in which an expansion mechanism (5) and a use side heat exchanger (6) are connected in order.
【０００９】そして、外気温度を検出する外気温度検出
手段(Tha) と、上記熱源側ファン(3b)の風量を制御する
ファン制御手段(12)とが設けられている。更に、上記外
気温度検出手段(Tha) の温度信号とファン制御手段(12)
の風量信号とを受けて、冷房運転時における外気温度が
予め設定された低温度で且つ熱源側ファン(3b)の風量が
予め設定された低風量になると低温信号を出力する低温
判別手段(13)と、該低温判別手段(13)が所定時間継続し
て低温信号を出力すると油回収信号を出力して油回収運
転を実行する油回収実行手段(14)とが設けれられてい
る。加えて、該油回収実行手段(14)が油回収信号を出力
すると上記熱源側ファン(3b)を停止させる停止信号を上
記ファン制御手段(12)に出力するファン停止手段(15)
と、上記油回収実行手段(14)が油回収運転を開始した
後、所定状態になると該油回収実行手段(14)の油回収運
転を終了させると共に、ファン停止手段(15)の停止制御
を終了させる復帰信号を出力する冷房復帰手段(17)とが
設けられた構成としている。There are provided an outside air temperature detecting means (Tha) for detecting the outside air temperature, and a fan control means (12) for controlling the air volume of the heat source side fan (3b). Further, the temperature signal of the outside air temperature detecting means (Tha) and the fan control means (12)
Low-temperature discrimination means (13) that outputs a low-temperature signal when the outside air temperature during the cooling operation is a preset low temperature and the air volume of the heat source side fan (3b) becomes the preset low air volume in response to the ) And an oil recovery execution means (14) for outputting an oil recovery signal and executing an oil recovery operation when the low temperature determination means (13) continuously outputs a low temperature signal for a predetermined time. In addition, when the oil recovery execution means (14) outputs an oil recovery signal, a fan stop means (15) that outputs a stop signal for stopping the heat source side fan (3b) to the fan control means (12).
After the oil recovery execution unit (14) starts the oil recovery operation, when the oil recovery execution unit (14) enters a predetermined state, the oil recovery execution unit (14) terminates the oil recovery operation and controls the stop of the fan stop unit (15). A cooling return means (17) for outputting a return signal for terminating the cooling operation is provided.
【００１０】また、請求項３に係る発明が講じた手段
は、上記請求項１又は２記載の発明において、冷媒回路
(9) の液ラインにはレシーバ(4) が設けられると共に、
該レシーバ(4) と冷媒回路(9) との間には、開閉弁(SV)
を備えて上記レシーバ(4) 内のガス冷媒を冷媒回路(9)
の低圧側にバイパスするバイパス路(4a)が設けれられる
一方、油回収実行手段(14)が油回収信号を出力すると上
記開閉弁(SV)を開動させる開閉弁制御手段(16)が設けら
れ、冷房復帰手段(17)は、上記油回収実行手段(14)が油
回収運転を開始した後、所定状態になると該油回収実行
手段(14)の油回収運転及びファン停止手段(15)の停止制
御を終了させると共に、上記開閉弁制御手段(16)が開閉
弁(SV)を閉動させる復帰信号を出力するように構成され
たものである。[0010] The means adopted by the invention according to claim 3 is the refrigerant circuit according to claim 1 or 2.
The liquid line of (9) is provided with a receiver (4),
An on-off valve (SV) is provided between the receiver (4) and the refrigerant circuit (9).
The gas refrigerant in the receiver (4) is provided with a refrigerant circuit (9).
On the other hand, a bypass path (4a) for bypassing is provided on the low pressure side of the valve, and on-off valve control means (16) for opening the on-off valve (SV) when the oil recovery execution means (14) outputs an oil recovery signal is provided. After the oil recovery execution means (14) starts the oil recovery operation, the cooling return means (17) starts the oil recovery operation of the oil recovery execution means (14) and the fan stop means (15) when a predetermined state is reached. In addition to terminating the stop control, the on-off valve control means (16) outputs a return signal for closing the on-off valve (SV).
【００１１】また、請求項４に係る発明が講じた手段
は、上記請求項１，２又は３記載の発明において、圧縮
機(1) の容量を制御する容量制御手段(11)が設けられる
一方、油回収実行手段(14)は、該容量制御手段(11)が所
定の低容量信号を出力している状態において低温判別手
段(13)が所定時間継続して低温信号を出力すると油回収
信号を出力して油回収運転を実行するように構成された
ものである。According to a fourth aspect of the present invention, in the first, second or third aspect, a capacity control means (11) for controlling a capacity of the compressor (1) is provided. The oil recovery execution means (14) outputs an oil recovery signal when the low temperature determination means (13) continuously outputs a low temperature signal for a predetermined time while the capacity control means (11) outputs a predetermined low capacity signal. Is output to execute an oil recovery operation.
【００１２】また、上記請求項１乃至４のうち何れか１
記載の発明において、請求項５に係る発明が講じた手段
は、冷房復帰手段(17)が、タイマ(T2)が所定時間を計数
すると復帰信号を出力するように構成され、また、請求
項６に係る発明が講じた手段は、冷房復帰手段(17)が、
圧縮機(1) の吐出側の高圧圧力を検出する高圧検出手段
(HS)が所定の高圧信号を出力すると復帰信号を出力する
ように構成されたものである。Further, any one of claims 1 to 4 above.
In the invention described in the above description, the means implemented by the invention according to claim 5 is characterized in that the cooling return means (17) is configured to output a return signal when the timer (T2) counts a predetermined time. Means taken by the invention according to the present invention, the cooling return means (17),
High pressure detection means for detecting the high pressure on the discharge side of the compressor (1)
(HS) outputs a return signal when a predetermined high voltage signal is output.
【００１３】[0013]
【作用】上記の構成により、請求項１に係る発明では、
先ず、冷媒回路(9) において、熱源側熱交換器(3) で凝
縮して液化した液冷媒が膨脹機構(5) で減圧された後、
利用側熱交換器(6) で蒸発し、圧縮機(1) に戻って冷房
運転を行う。この冷房運転時において、飽和温度検出手
段(Thc) が凝縮圧力相当飽和温度を検出しており、該飽
和温度検出手段(Thc) の温度信号を低温判別手段(13)が
受けて、冷房運転時における凝縮圧力相当飽和温度が予
め設定された低温度になると低温信号を出力することに
なる。続いて、該低温判別手段(13)が所定時間継続して
低温信号を出力すると、油回収実行手段(14)が油回収信
号を出力して油回収運転を実行すると同時に、該油回収
実行手段(14)が油回収信号を出力すると、ファン停止手
段(15)が上記熱源側ファン(3b)を停止して高圧圧力を上
昇させ、冷媒の循環量を増大させて潤滑油を圧縮機(1)
に回収する。その後、冷房復帰手段(17)は、上記油回収
実行手段(14)が油回収運転を開始した後、所定状態にな
ると、具体的に、請求項５に係る発明では、タイマ(T2)
が所定時間を計数すると、また、請求項６に係る発明で
は、高圧圧力が所定圧力になると、油回収実行手段(14)
の油回収運転を終了させると共に、ファン停止手段(15)
の停止制御を終了させる復帰信号を出力して冷房運転を
再開させることになる。According to the first aspect of the present invention,
First, in the refrigerant circuit (9), the liquid refrigerant condensed and liquefied in the heat source side heat exchanger (3) is decompressed by the expansion mechanism (5).
Evaporate in the use side heat exchanger (6) and return to the compressor (1) to perform cooling operation. During the cooling operation, the saturation temperature detecting means (Thc) detects the saturation temperature corresponding to the condensing pressure, and the low-temperature discriminating means (13) receives the temperature signal of the saturation temperature detecting means (Thc), and performs the cooling operation. When the saturated temperature corresponding to the condensing pressure in the above becomes a preset low temperature, a low temperature signal is output. Subsequently, when the low temperature determining means (13) continuously outputs a low temperature signal for a predetermined time, the oil recovery executing means (14) outputs an oil recovery signal to execute the oil recovery operation, and When (14) outputs the oil recovery signal, the fan stopping means (15) stops the heat source side fan (3b) to increase the high pressure, increase the circulation amount of the refrigerant, and remove the lubricating oil from the compressor (1). )
To be collected. After that, the cooling return means (17), when the oil recovery execution means (14) starts the oil recovery operation and enters a predetermined state, specifically, in the invention according to claim 5, the timer (T2)
Counts a predetermined time, and in the invention according to claim 6, when the high pressure reaches the predetermined pressure, the oil recovery execution means (14)
End the oil recovery operation and fan stop means (15)
Then, a return signal for terminating the stop control is output to restart the cooling operation.
【００１４】また、請求項２に係る発明では、外気温度
検出手段(Tha) が外気温度を検出する一方、ファン制御
手段(12)が熱源側ファン(3b)の風量を制御している。そ
して、低温判別手段(13)が上記外気温度検出手段(Tha)
の温度信号とファン制御手段(12)の風量信号とを受け
て、冷房運転時における外気温度が予め設定された低温
度で且つ熱源側ファン(3b)の風量が予め設定された低風
量になると低温信号を出力することになる。続いて、油
回収実行手段(14)は、低温判別手段(13)が所定時間継続
して低温信号を出力すると、油回収信号を出力して油回
収運転を実行すると同時に、ファン停止手段(15)は該油
回収実行手段(14)が油回収信号を出力すると上記熱源側
ファン(3b)を停止させる停止信号を上記ファン制御手段
(12)に出力して圧縮機(1) に潤滑油を回収することにな
る。その後、冷房復帰手段(17)は、上記油回収実行手段
(14)が油回収運転を開始した後、所定状態になると該油
回収実行手段(14)の油回収運転を終了させると共に、フ
ァン停止手段(15)の停止制御を終了させて冷房運転を再
開させることになる。In the invention according to claim 2, the outside air temperature detecting means (Tha) detects the outside air temperature, while the fan control means (12) controls the air flow of the heat source side fan (3b). And the low temperature determining means (13) is the outside air temperature detecting means (Tha)
Receiving the temperature signal and the air flow signal of the fan control means (12), when the outside air temperature during the cooling operation is a predetermined low temperature and the air flow of the heat source side fan (3b) becomes the predetermined low air flow. A low temperature signal will be output. Subsequently, when the low-temperature determining means (13) continuously outputs the low-temperature signal for a predetermined time, the oil-recovery executing means (14) outputs an oil-recovery signal to execute the oil recovery operation, and at the same time, executes the fan-stopping means (15 ) Sends a stop signal for stopping the heat source side fan (3b) when the oil recovery execution means (14) outputs an oil recovery signal, to the fan control means.
The lubricating oil is output to the compressor (1) and output to the compressor (1). Thereafter, the cooling return means (17) is
When a predetermined state is reached after (14) starts the oil recovery operation, the oil recovery operation of the oil recovery execution means (14) is terminated, and the stop control of the fan stop means (15) is terminated to restart the cooling operation. Will be.
【００１５】また、請求項３に係る発明では、上記請求
項１又は２記載の発明において、油回収実行手段(14)が
油回収運転を開始すると、開閉弁制御手段(16)がバイパ
ス路(4a)の開閉弁(SV)を開動し、レシーバ(4) 内の高圧
ガス冷媒を低圧側にバイパスして高圧圧力の上昇を抑制
することになる。According to a third aspect of the present invention, when the oil recovery execution means (14) starts the oil recovery operation, the on-off valve control means (16) switches the bypass passage ( By opening the open / close valve (SV) in 4a), the high-pressure gas refrigerant in the receiver (4) is bypassed to the low-pressure side to suppress the rise in high-pressure.
【００１６】また、請求項４に係る発明では、上記請求
項１，２又は３記載の発明において、容量制御手段(11)
が圧縮機(1) の容量を制御しており、油回収実行手段(1
4)は、該容量制御手段(11)が所定の低容量信号を出力
し、潤滑油が不足する状態において低温判別手段(13)が
所定時間継続して低温信号を出力すると油回収運転を実
行することになる。According to a fourth aspect of the present invention, in the above-mentioned first, second or third aspect, the capacity control means (11) is provided.
Controls the capacity of the compressor (1), and the oil recovery execution means (1
4) executes the oil recovery operation when the capacity control means (11) outputs a predetermined low capacity signal and the low temperature determination means (13) continuously outputs a low temperature signal for a predetermined time in a state where the lubricating oil is insufficient. Will do.
【００１７】[0017]
【発明の効果】従って、請求項１に係る発明によれば、
冷房運転時における油回収運転時に熱源側ファン(3b)を
停止するようにしたために、圧縮機(1) の吐出側の高圧
圧力を上昇させることができるので、圧縮機(1) の吸込
側の低圧圧力を上昇させることができ、特に、低外気温
の冷房運転時に低圧圧力を確実に上昇させることができ
る。この結果、オイルフォーミング等を確実に防止する
ことができることから、圧縮機(1) 内の潤滑油不足を確
実に防止することができる。また、上記油回収時に圧縮
機(1) の容量を増大することがないので、快適な室温制
御を行うことがでる。Therefore, according to the first aspect of the present invention,
Since the heat source side fan (3b) is stopped during the oil recovery operation during the cooling operation, the high pressure on the discharge side of the compressor (1) can be increased, so the suction side of the compressor (1) The low-pressure pressure can be increased, and in particular, the low-pressure pressure can be reliably increased during a cooling operation at a low outside air temperature. As a result, since oil forming and the like can be reliably prevented, shortage of lubricating oil in the compressor (1) can be reliably prevented. Further, since the capacity of the compressor (1) does not increase at the time of the oil recovery, comfortable room temperature control can be performed.
【００１８】また、請求項２に係る発明によれば、熱源
側ファン(3b)の風量で油回収時を判別するようにしたた
めに、該熱源側ファン(3b)の風量を凝縮圧力相当飽和温
度で制御していることから、簡素なロジックでもって油
回収運転を制御することができる。According to the second aspect of the present invention, since the time of oil recovery is determined by the air flow rate of the heat source side fan (3b), the air flow rate of the heat source side fan (3b) is determined by the condensing pressure equivalent saturation temperature. , The oil recovery operation can be controlled with a simple logic.
【００１９】また、請求項３に係る発明によれば、油回
収時に開閉弁(SV)を開動させるようにしたために、高圧
冷媒を低圧側にバイパスすることができるので、高圧圧
力の異常上昇を防止することができることから、異常停
止等を未然に防止して運転制御性を向上させることがで
きる。According to the third aspect of the present invention, since the on-off valve (SV) is opened at the time of oil recovery, the high-pressure refrigerant can be bypassed to the low-pressure side. Since it can be prevented, abnormal stop and the like can be prevented beforehand, and the operation controllability can be improved.
【００２０】また、請求項４に係る発明によれば、圧縮
機(1) が低容量運転時のみ油回収を行うようにしたため
に、必要な油回収運転のみを行うことができるので、冷
房運転の快適性を向上させることができる。According to the fourth aspect of the present invention, since the compressor (1) recovers oil only during low-capacity operation, only the necessary oil recovery operation can be performed. Comfort can be improved.
【００２１】また、請求項５に係る発明によれば、タイ
マ(T2)によって油回収運転を終了するようにしたため
に、各種の終了センサを要しないので、簡単な構成でも
って油回収運転を制御することができる。According to the fifth aspect of the present invention, since the oil recovery operation is terminated by the timer (T2), various end sensors are not required, so that the oil recovery operation can be controlled with a simple configuration. can do.
【００２２】また、請求項６に係る発明によれば、高圧
圧力によって油回収運転を終了するようにしたために、
該油回収運転を必要時間行うことができるので、冷房運
転を迅速に再開することができる。According to the sixth aspect of the present invention, the oil recovery operation is terminated by the high pressure.
Since the oil recovery operation can be performed for a required time, the cooling operation can be quickly restarted.
【００２３】[0023]
【実施例】以下、本発明の実施例を図面に基づいて詳細
に説明する。図３は、本発明を適用した空気調和装置の
冷媒配管系統を示し、一台の室外ユニット(A) に対して
一台の室内ユニット(B) が接続されたいわゆるセパレー
トタイプのものである。上記室外ユニット(A) には、イ
ンバータにより運転周波数を可変に調節されるスクロー
ルタイプの圧縮機(1) と、冷房運転時には図中実線のご
とく、暖房運転時には図中破線のごとく切換わる四路切
換弁(2) と、冷房運転時には凝縮器として、暖房運転時
には蒸発器として機能する熱源側熱交換器である室外熱
交換器(3) と、冷媒を減圧するための減圧部(20)とが主
要機器として配置されている。また、室内ユニット(B)
には、冷房運転時には蒸発器として、暖房運転時には凝
縮器として機能する利用側熱交換器である室内熱交換器
(6) が配置されている。そして、上記圧縮機(1) と四路
切換弁(2) と室外熱交換器(3) と減圧部(20)と室内側熱
交換器(6) とは、配管(8) により順次接続され、冷媒の
循環により熱移動を生ぜしめるようにした冷媒回路(9)
が構成されている。更に、上記室外熱交換器(3) には、
熱源側ファンである室外ファン(3b)が、室内熱交換器
(6) には、利用側ファンである室内ファン(6a)がそれぞ
れ付設されている。Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 3 shows a refrigerant piping system of an air conditioner to which the present invention is applied, which is a so-called separate type in which one outdoor unit (A) is connected to one indoor unit (B). The outdoor unit (A) includes a scroll-type compressor (1) whose operating frequency is variably adjusted by an inverter, and four paths that switch as shown by the solid line in the cooling operation and as shown by the broken line in the heating operation. A switching valve (2), an outdoor heat exchanger (3) which is a heat source side heat exchanger functioning as a condenser during cooling operation and as an evaporator during heating operation, and a decompression unit (20) for decompressing the refrigerant. Are arranged as main equipment. Also, indoor unit (B)
The indoor heat exchanger is a utilization side heat exchanger that functions as an evaporator during cooling operation and as a condenser during heating operation.
(6) is arranged. The compressor (1), the four-way switching valve (2), the outdoor heat exchanger (3), the pressure reducing unit (20), and the indoor heat exchanger (6) are sequentially connected by a pipe (8). , A refrigerant circuit (9) that causes heat transfer by circulation of the refrigerant
Is configured. Furthermore, in the outdoor heat exchanger (3),
The outdoor fan (3b), which is the heat source side fan, is
In (6), an indoor fan (6a) as a use-side fan is additionally provided.
【００２４】ここで、上記減圧部(20)は、ブリッジ状の
整流回路(8r)と、該整流回路(8r)における一対の接続点
(P, Q)に接続された共通路(8a)とを備え、該共通路(8a)
には、液冷媒を貯溜するためのレシーバ(4) と、室外熱
交換器(3) の補助熱交換器(3a)と、液冷媒の減圧機能及
び流量調節機能を有する膨脹機構である電動膨脹弁(5)
とが直列に配置されている。そして、上記整流回路(8r)
における他の一対の接続点(R, S)には、室外熱交換器
(3) 側の配管(8) と室内熱交換器(6) 側の配管(8) とが
接続されている。更に、上記整流回路(8r)は、上記共通
路(8a)の上流側接続点(P) と室外熱交換器(3) 側の接続
点(S) とを繋ぎ外熱交換器(3) からレシーバ(4) への冷
媒流通のみを許容する第１逆止弁(D1)を備えた第１流入
路(8b1) と、上記共通路(8a)の上流側接続点(P) と室内
熱交換器(6) 側の接続点(R) とを繋ぎ室内熱交換器(6)
からレシーバ(4) への冷媒流通のみを許容する第２逆止
弁(D2)を備えた第２流入路(8b2) と、上記共通路(8a)の
下流側接続点(Q) と室内熱交換器(6) 側の接続点(R) と
を繋ぎ電動膨脹弁(5) から室内熱交換器(6) への冷媒流
通のみを許容する第３逆止弁(D3)を備えた第１流出路(8
c1) と、上記共通路(8a)の下流側接続点(Q) と、室外熱
交換器(3) 側の接続点(S) とを繋ぎ電動膨脹弁(5) から
室外熱交換器(3) への冷媒流通のみを許容する第４逆止
弁(D4)を備えた第２流出路(8c2) とが設けられている。Here, the pressure reducing section (20) includes a bridge-shaped rectifier circuit (8r) and a pair of connection points in the rectifier circuit (8r).
(P, Q) connected to a common path (8a), said common path (8a)
There is a receiver (4) for storing the liquid refrigerant, an auxiliary heat exchanger (3a) for the outdoor heat exchanger (3), and an electric expansion which is an expansion mechanism having a function of reducing the pressure of the liquid refrigerant and a function of adjusting the flow rate. Valve (5)
And are arranged in series. And the rectifier circuit (8r)
The other pair of connection points (R, S) in
The pipe (8) on the (3) side and the pipe (8) on the indoor heat exchanger (6) side are connected. Further, the rectifier circuit (8r) connects the upstream connection point (P) of the common path (8a) to the connection point (S) on the outdoor heat exchanger (3) side, and connects the rectifier circuit (8r) from the outdoor heat exchanger (3). Indoor heat exchange with a first inflow path (8b1) having a first check valve (D1) allowing only refrigerant flow to the receiver (4), and an upstream connection point (P) of the common path (8a); Indoor heat exchanger (6) by connecting to the connection point (R) on the side of the heat exchanger (6)
A second inflow path (8b2) provided with a second check valve (D2) that allows only refrigerant flow from the receiver to the receiver (4); a downstream connection point (Q) of the common path (8a); A first check valve (D3) having a third check valve (D3) that connects the connection point (R) on the side of the exchanger (6) and allows only refrigerant to flow from the electric expansion valve (5) to the indoor heat exchanger (6). Outflow channel (8
c1), a connection point (Q) on the downstream side of the common path (8a) and a connection point (S) on the outdoor heat exchanger (3) side, and the electric expansion valve (5) is connected to the outdoor heat exchanger (3). And a second outflow path (8c2) provided with a fourth check valve (D4) that allows only the flow of the refrigerant to (8).
【００２５】また、上記整流回路(8r)における共通路(8
a)の両接続点(P, Q)の間には、キャピラリチューブ(C)
を介設してなる液封防止バイパス路(8f)が設けられ、該
液封防止バイパス路(8f)により、圧縮機(1) の停止時に
おける液封を防止している。一方、上記レシーバ(4) の
上部と、冷媒回路(9) の低圧側、つまり、共通路(8a)に
おける電動膨脹弁(5) より下流側との間には、開閉弁(S
V)を備えたバイパス路であるガス抜き路(4a)が接続され
ている。尚、上記キャピラリチューブ(C) の減圧度は電
動膨脹弁(5) よりも十分大きくなるように設定されてい
て、通常運転時における電動膨脹弁(5) による冷媒流量
調節機能を良好に維持しうるようになされている。ま
た、(F1 〜 F5)は、冷媒中の塵埃を除去するためのフィ
ルタ、(ER)は、圧縮機(1) の運転音を低減させるための
消音器である。The common path (8) in the rectifier circuit (8r)
a) Capillary tube (C) between both connection points (P, Q)
There is provided a liquid seal prevention bypass passage (8f) interposed therebetween, and the liquid seal prevention bypass passage (8f) prevents liquid seal when the compressor (1) is stopped. On the other hand, between the upper part of the receiver (4) and the low pressure side of the refrigerant circuit (9), that is, the downstream side of the electric expansion valve (5) in the common path (8a), an on-off valve (S
A degassing path (4a), which is a bypass having V), is connected. The degree of pressure reduction of the capillary tube (C) is set to be sufficiently larger than that of the electric expansion valve (5), so that the function of adjusting the refrigerant flow rate by the electric expansion valve (5) during normal operation is maintained well. It has been made possible. (F1 to F5) are filters for removing dust in the refrigerant, and (ER) is a muffler for reducing the operation noise of the compressor (1).
【００２６】更に、上記空気調和装置にはセンサ類が設
けられていて、 (Thd)は、圧縮機(1) の吐出管に配置さ
れて吐出管温度Tdを検出する吐出管センサ、 (Tha)は、
室外ユニット(A) の空気吸込口に配置されて外気温度Ta
を検出する外気温度検出手段である外気温センサ、 (Th
c)は、室外熱交換器(3) に配置されて、冷房運転時には
凝縮温度（凝縮圧力相当飽和温度）となり、暖房運転時
には蒸発温度となる外熱交温度Tcを検出する飽和温度検
出手段である外熱交センサ、 (Thr)は、室内ユニット
(B) の空気吸込口に配置されて室内温度Trを検出する室
温センサ、 (The)は、室内熱交換器(6) に配置されて、
冷房運転時には蒸発温度となり、暖房運転時には凝縮温
度となる内熱交温度Teを検出する内熱交センサ、 (HPS)
は、高圧冷媒圧力を検出して、該高圧冷媒圧力の過上昇
によりオンとなって高圧信号を出力する高圧圧力スイッ
チ、 (LPS)は、低圧冷媒圧力を検出して、該低圧冷媒圧
力の過低下によりオンとなって低圧信号を出力する低圧
圧力スイッチである。Further, the air conditioner is provided with sensors and the like. (Thd) is a discharge pipe sensor that is disposed on the discharge pipe of the compressor (1) and detects the discharge pipe temperature Td. Is
Located at the air intake of the outdoor unit (A)
An outside air temperature sensor, which is an outside air temperature detecting means for detecting
c) is a saturation temperature detecting means arranged in the outdoor heat exchanger (3) for detecting an external heat exchange temperature Tc which becomes a condensing temperature (saturation temperature corresponding to condensing pressure) during a cooling operation, and becomes an evaporating temperature during a heating operation. An external heat exchange sensor, (Thr) is an indoor unit
(B) a room temperature sensor that is disposed at the air suction port and detects the indoor temperature Tr, (The) is disposed at the indoor heat exchanger (6),
An internal heat exchange sensor that detects the internal heat exchange temperature Te, which becomes the evaporating temperature during cooling operation and becomes the condensing temperature during heating operation, (HPS)
Is a high pressure switch that detects a high pressure refrigerant pressure and is turned on to output a high pressure signal when the high pressure refrigerant pressure is excessively increased. (LPS) detects a low pressure refrigerant pressure and detects an excess of the low pressure refrigerant pressure. This is a low-pressure switch that is turned on by a drop to output a low-pressure signal.
【００２７】そして、上記各センサ(Thd, 〜 ,The)及び
各スイッチ(HPS, LPS)の出力信号は、コントローラ(10)
に入力されており、該コントローラ(10)は、入力信号に
基づいて空調運転を制御するように構成されている。上
述した冷媒回路(9) において、冷房運転時には、室外熱
交換器(3) で凝縮して液化した液冷媒が第１流入路(8b
1) から流入し、第１逆止弁(D1)を経てレシーバ(4) に
貯溜され、電動膨脹弁(5) で減圧された後、第１流出路
(8c1) を経て室内熱交換器(6) で蒸発して圧縮機(1) に
戻る循環となる一方、暖房運転時には、室内熱交換器
(6) で凝縮して液化した液冷媒が第２流入路(8b2) から
流入し、第２逆止弁(D2)を経てレシーバ(4) に貯溜さ
れ、電動膨脹弁(5) で減圧された後、第２流出路(8c2)
を経て室外熱交換器(3) で蒸発して圧縮機(1) に戻る循
環となる。The output signals of the sensors (Thd,..., The) and the switches (HPS, LPS) are sent to the controller (10).
The controller (10) is configured to control the air-conditioning operation based on the input signal. In the refrigerant circuit (9) described above, during the cooling operation, the liquid refrigerant condensed and liquefied in the outdoor heat exchanger (3) is supplied to the first inflow path (8b).
1), is stored in the receiver (4) through the first check valve (D1), and is decompressed by the electric expansion valve (5).
After passing through (8c1), it evaporates in the indoor heat exchanger (6) and returns to the compressor (1).
The liquid refrigerant condensed and liquefied in (6) flows in from the second inflow path (8b2), is stored in the receiver (4) through the second check valve (D2), and is decompressed by the electric expansion valve (5). After the second outflow (8c2)
After that, it evaporates in the outdoor heat exchanger (3) and returns to the compressor (1).
【００２８】一方、上記コントローラ(10)には、圧縮機
(1) の容量制御手段(11)と室外ファン(3b)のファン制御
手段(12)とが設けられると共に、請求項２，３及び５に
係る発明の特徴として、油回収運転を制御するための低
温判別手段(13)と油回収実行手段(14)とファン停止手段
(15)と開閉弁制御手段(16)と冷房復帰手段(17)とが設け
られている。そして、上記容量制御手段(11)は、インバ
ータの運転周波数を零から最大周波数まで２０ステップ
Ｎに区分して、各周波数ステップＮを吐出管温度Tdに基
づいて設定して圧縮機(1) の容量を制御するように構成
されている。また、上記ファン制御手段(12)は、図５に
示すように、外熱交センサ(Thc) の外熱交温度Tcに基づ
いて高風量のＨタップと低風量のＬタップとに室外ファ
ン(3b)の風量を制御するように構成されている。具体的
に、該ファン制御手段(12)は、室外ファン(3b)の風量が
Ｈタップの状態において外熱交温度Tcが２４℃以上から
２４℃より低下するとＬタップに切換える一方、室外フ
ァン(3b)の風量がＬタップの状態において外熱交温度Tc
が４３℃以下から４３℃より上昇するとＨタップに切換
えるように構成されている。On the other hand, the controller (10) includes a compressor
In addition to the capacity control means (11) of (1) and the fan control means (12) of the outdoor fan (3b), the invention according to claims 2, 3 and 5 is characterized by Low temperature determining means (13), oil recovery executing means (14) and fan stopping means
(15), on-off valve control means (16) and cooling return means (17) are provided. The capacity control means (11) divides the operating frequency of the inverter into 20 steps N from zero to the maximum frequency, sets each frequency step N based on the discharge pipe temperature Td, and sets the frequency step N of the compressor (1). It is configured to control the capacity. As shown in FIG. 5, the fan control means (12) includes an outdoor fan (L) having a high air volume and an L tap having a low air volume based on the external heat exchange temperature Tc of the external heat exchange sensor (Thc). It is configured to control the air volume of 3b). Specifically, the fan control means (12) switches to the L tap when the outside heat exchange temperature Tc falls below 24 ° C. from 24 ° C. or more while the air flow of the outdoor fan (3b) is H tap, while the outdoor fan (3b) The external heat exchange temperature Tc when the air volume of 3b) is L tap
When the temperature rises from 43 ° C. or lower to 43 ° C., the tap is switched to the H tap.
【００２９】一方、上記低温判別手段(13)は、外気温セ
ンサ(Tha) の温度信号とファン制御手段(12)の風量信号
とを受けて、冷房運転時における外気温度Taが予め設定
された低温度で且つ室外ファン(3b)の風量が予め設定さ
れた低風量になると低温信号を出力するように構成さ
れ、具体的に、低温判別手段(13)は、図５の斜線部に示
すように、外気温度Taが３℃より低く、且つ室外ファン
(3b)がＬタップであると、低温信号を出力するように構
成されている。また、上記油回収実行手段(14)は、開始
タイマ(T1)を備え、該低温判別手段(13)が所定時間継続
して低温信号を出力すると油回収信号を出力して油回収
運転を実行するように構成され、つまり、低外気冷房時
において、外気温度Taが３℃より低く、且つ室外ファン
(3b)がＬタップの状態が１６分継続すると、冷媒循環量
が少ないので、油回収運転を実行することになる。ま
た、上記ファン停止手段(15)は、上記油回収実行手段(1
4)が油回収信号を出力して油回収運転が開始されると、
上記室外ファン(3b)を停止させる停止信号を上記ファン
制御手段(12)に出力し、冷媒回路(9) の高圧圧力を上昇
させるように構成されている。また、上記開閉弁制御手
段(16)は、油回収実行手段(14)が油回収信号を出力して
油回収運転が開始されると、上記開閉弁(SV)を開動させ
てレシーバ(4) 内の高圧ガス冷媒を低圧側にバイパスさ
せるように構成されている。また、上記冷房復帰手段(1
7)は、終了タイマ(T2)を備え、油回収実行手段(14)が油
回収運転を開始した後、該終了タイマ(T2)が２０秒を計
数すると、該油回収実行手段(14)の油回収運転及びファ
ン停止手段(15)の停止制御を終了させると共に、上記開
閉弁制御手段(16)が開閉弁(SV)を閉動させる復帰信号を
出力し、冷房運転を再開させるように構成されている。On the other hand, the low temperature determining means (13) receives the temperature signal of the outside air temperature sensor (Tha) and the air flow signal of the fan control means (12), and sets the outside air temperature Ta during the cooling operation in advance. It is configured to output a low-temperature signal when the temperature is low and the air volume of the outdoor fan (3b) becomes a preset low air volume. Specifically, the low-temperature discriminating means (13) is configured as shown by a hatched portion in FIG. In addition, the outside air temperature Ta is lower than 3 ° C and the outdoor fan
If (3b) is an L tap, a low temperature signal is output. Further, the oil recovery execution means (14) includes a start timer (T1), and when the low temperature determination means (13) outputs a low temperature signal continuously for a predetermined time, outputs an oil recovery signal to execute the oil recovery operation. That is, in the low outdoor air cooling, the outdoor air temperature Ta is lower than 3 ° C., and the outdoor fan
If (3b) continues the state of the L tap for 16 minutes, the amount of circulating refrigerant is small, so that the oil recovery operation is executed. Further, the fan stopping means (15) is provided with the oil recovery executing means (1).
4) outputs the oil recovery signal and the oil recovery operation starts,
A stop signal for stopping the outdoor fan (3b) is output to the fan control means (12) to increase the high pressure of the refrigerant circuit (9). Further, when the oil recovery execution means (14) outputs an oil recovery signal and the oil recovery operation is started, the on-off valve control means (16) opens the on-off valve (SV) to open the receiver (4). The high-pressure gas refrigerant inside is bypassed to the low-pressure side. Further, the cooling return means (1
7) is provided with an end timer (T2), and after the oil recovery execution means (14) starts the oil recovery operation and the end timer (T2) counts 20 seconds, the oil recovery execution means (14) In addition to terminating the oil recovery operation and the stop control of the fan stop means (15), the on-off valve control means (16) outputs a return signal for closing the on-off valve (SV) and restarts the cooling operation. Have been.
【００３０】ここで、上記油回収運転時において、室外
ファン(3b)を停止する共に、開閉弁(SV)を開動するよう
にした基本的理由について説明する。先ず、図７に示す
ように、室外ファン(3b)を停止すると、室外熱交換器
(3) において冷媒から外気に対して放熱が行われないの
で、高温高圧の冷媒が凝縮しないまま室外熱交換器(3)
を流れるので、高圧圧力は急上昇することになる。この
結果、低圧圧力が上昇し、比体積が小さくなって冷媒循
環量が上昇し、潤滑油が圧縮機(1) に回収されることに
なる。また、図８に示すように、開閉弁(SV)を開動する
と、レシーバ(4) の上部よりガス冷媒がガス抜き路(4a)
を通って室内熱交換器(6) に流れることになり、液冷媒
がレシーバ(4) に溜り、高圧圧力が低下することにな
る。そこで、図９に示すように、室外ファン(3b)を停止
すると共に、開閉弁(SV)を開動すると、高圧圧力の上昇
が緩やかになり、高圧圧力の制御性が向上することにな
る。このことから、油回収運転時において、室外ファン
(3b)と開閉弁(SV)を制御し、高圧圧力を制御して油回収
運転を制御するようにしている。Here, the basic reason for stopping the outdoor fan (3b) and opening the on-off valve (SV) during the oil recovery operation will be described. First, as shown in FIG. 7, when the outdoor fan (3b) is stopped, the outdoor heat exchanger is stopped.
Since the refrigerant does not radiate heat to the outside air in (3), the outdoor heat exchanger (3)
, The high pressure rises sharply. As a result, the low pressure increases, the specific volume decreases, the refrigerant circulation rate increases, and the lubricating oil is collected in the compressor (1). As shown in FIG. 8, when the on-off valve (SV) is opened, the gas refrigerant flows from the upper part of the receiver (4) to the gas venting path (4a).
Then, the refrigerant flows into the indoor heat exchanger (6), the liquid refrigerant accumulates in the receiver (4), and the high pressure decreases. Therefore, as shown in FIG. 9, when the outdoor fan (3b) is stopped and the on-off valve (SV) is opened, the high pressure is gradually increased, and the controllability of the high pressure is improved. This indicates that the outdoor fan
(3b) and the on-off valve (SV) are controlled, and the high pressure is controlled to control the oil recovery operation.
【００３１】次に、上記空気調和装置における油回収運
転の制御動作について、図４の制御フローに基づき説明
する。先ず、油回収制御ルーチンに移ると、ステップST
１において、外気温センサ(Tha) の温度信号を受けて外
気温度Taが３℃より低いか否かを判定し、該外気温度Ta
が３℃以上である場合には、該ステップST１の判定がＮ
Ｏとなり、油回収運転を行うことなくリターンする一
方、上記外気温度Taが３℃より低くなると、ステップST
１の判定がＹＥＳとなってステップST２に移ることにな
る。該ステップST２において、ファン制御手段(12)の風
量信号を受けて室外ファン(3b)がＬタップであるか否か
を判定し、該室外ファン(3b)がＨタップである場合には
（図６Ａ参照）、該ステップST２の判定がＮＯとなり、
油回収運転を行うことなくリターンする一方、上記室外
ファン(3b)がＬタップであると、ステップST２の判定が
ＹＥＳとなってステップST３に移ることになる。Next, the control operation of the oil recovery operation in the air conditioner will be described with reference to the control flow of FIG. First, moving to the oil recovery control routine, step ST
In step 1, it is determined whether or not the outside air temperature Ta is lower than 3 ° C. based on the temperature signal of the outside air temperature sensor (Tha).
Is 3 ° C. or more, the determination in step ST1 is N
O, the process returns without performing the oil recovery operation. On the other hand, if the outside air temperature Ta becomes lower than 3 ° C., step ST
The determination of 1 is YES, and the process moves to step ST2. In the step ST2, it is determined whether or not the outdoor fan (3b) has the L tap in response to the air volume signal of the fan control means (12). If the outdoor fan (3b) has the H tap (FIG. 6A), the determination in step ST2 is NO,
If the return is made without performing the oil recovery operation and the outdoor fan (3b) is the L tap, the determination in step ST2 becomes YES and the process proceeds to step ST3.
【００３２】次いで、このステップST３において、油回
収実行手段(14)が開始タイマ(T1)をスタートさせた後、
ステップST４に移り、該開始タイマ(T1)が１６分を計数
したか否かを判定し、該開始タイマ(T1)が１６分を計数
するまでステップST４の判定がＮＯとなってリターンし
て通常制御を行う一方、上記外気温度Taが３℃より低
く、室外ファン(3b)がＬタップである状態が１６分係属
すると（図６Ｂ参照）、上記ステップST４の判定がＹＥ
ＳとなってステップST５に移ることになる。そして、該
ステップST５において、油回収実行手段(14)が油回収運
転を開始して上記開始タイマ(T1)をリセットすることに
なる（図６Ｃ参照）。その際、圧縮機(1)の周波数ステ
ップＮ（容量）は冷房運転時のままで油回収運転を実行
する。続いて、上記ステップST５からステップST６に移
り、ファン停止手段(15)は、油回収実行手段(14)が油回
収運転を開始すると、上記室外ファン(3b)を停止させ、
高圧圧力を上昇させる。同時に、ステップST７に移り、
開閉弁制御手段(16)は、開閉弁(SV)を開動させてレシー
バ(4) 内の高圧ガス冷媒を低圧側にバイパスさせて高圧
圧力の上昇を抑制する。その後、上記ステップST７から
ステップST８に移り、冷房復帰手段(17)は、終了タイマ
(T2)をスタートさせ、ステップST９に移り、該終了タイ
マ(T2)が２０秒を計数したか否かを判定し、２０秒が経
過するまで該ステップST９に待機して油回収運転を行う
ことになる。そして、上記終了タイマ(T2)が２０秒を計
数すると、ステップST10に移り、冷房復帰手段(17)は、
復帰信号を出力し、上記油回収実行手段(14)の油回収運
転及びファン停止手段(15)の停止制御を終了させると共
に、上記開閉弁制御手段(16)が開閉弁(SV)を閉動させて
通常の冷房運転を再開させてリターンし、上述した動作
を繰返すことになる。尚、暖房運転時は、圧縮機(1) の
周波数ステップＮが低い所定の低容量で２時間継続して
運転すると、該周波数ステップＮを大きくして５分間油
回収運転を行うことになる。Next, in step ST3, after the oil recovery execution means (14) starts the start timer (T1),
The process proceeds to step ST4, where it is determined whether or not the start timer (T1) has counted 16 minutes. Until the start timer (T1) has counted 16 minutes, the determination in step ST4 becomes NO, and the routine returns. On the other hand, if the outside air temperature Ta is lower than 3 ° C. and the state in which the outdoor fan (3b) is the L tap is engaged for 16 minutes (see FIG. 6B), the determination in step ST4 is YE.
The result is S, and the process proceeds to step ST5. Then, in step ST5, the oil recovery execution means (14) starts the oil recovery operation and resets the start timer (T1) (see FIG. 6C). At this time, the oil recovery operation is executed while the frequency step N (capacity) of the compressor (1) is in the cooling operation. Subsequently, the process proceeds from step ST5 to step ST6, and when the oil recovery execution means (14) starts the oil recovery operation, the fan stopping means (15) stops the outdoor fan (3b),
Increase high pressure. At the same time, move to step ST7,
The on-off valve control means (16) opens the on-off valve (SV) to bypass the high-pressure gas refrigerant in the receiver (4) to the low-pressure side, thereby suppressing an increase in high-pressure. Thereafter, the process proceeds from step ST7 to step ST8, in which the cooling return means (17)
(T2) is started, the process proceeds to step ST9, it is determined whether or not the end timer (T2) has counted 20 seconds, and the oil recovery operation is performed by waiting in step ST9 until 20 seconds have elapsed. become. Then, when the end timer (T2) has counted 20 seconds, the process proceeds to step ST10, in which the cooling return means (17)
A return signal is output, the oil recovery operation of the oil recovery execution means (14) and the stop control of the fan stop means (15) are terminated, and the on-off valve control means (16) closes the on-off valve (SV). Then, the normal cooling operation is restarted and the process returns, and the above-described operation is repeated. During the heating operation, if the compressor (1) is continuously operated for 2 hours at a predetermined low capacity with a low frequency step N, the frequency step N is increased and the oil recovery operation is performed for 5 minutes.
【００３３】以上のように、本実施例によれば、冷房運
転時における油回収運転時に室外ファン(3b)を停止する
ようにしたために、圧縮機(1) の吐出側の高圧圧力を上
昇させることができるので、圧縮機(1) の吸込側の低圧
圧力を上昇させることができ、特に、低外気温の冷房運
転時に低圧圧力を確実に上昇させることができる。この
結果、オイルフォーミング等を確実に防止することがで
きることから、圧縮機(1) 内の潤滑油不足を確実に防止
することができる。また、上記油回収時に圧縮機(1) の
容量を増大することがないので、快適な室温制御を行う
ことがでる。また、上記室外ファン(3b)の風量（Ｌタッ
プ）で油回収時を判別するようにしたために、該室外フ
ァン(3b)の風量を外熱交温度Tcで制御しているので、簡
素なロジックでもって油回収運転を制御することができ
る。また、上記油回収時に開閉弁(SV)を開動させるよう
にしたために、レシーバ(4) 内の高圧ガス冷媒を低圧側
にバイパスすることができるので、高圧圧力の異常上昇
を防止することができることから、異常停止等を未然に
防止して運転制御性を向上させることができる。また、
上記冷房復帰手段(17)が終了タイマ(T2)によって復帰信
号を出力し、油回収運転を終了するようにしたために、
各種の終了センサを要しないので、簡単な構成でもって
油回収運転を制御することができる。As described above, according to this embodiment, since the outdoor fan (3b) is stopped during the oil recovery operation during the cooling operation, the high pressure on the discharge side of the compressor (1) is increased. Therefore, the low-pressure pressure on the suction side of the compressor (1) can be increased, and the low-pressure pressure can be reliably increased particularly during the cooling operation at a low outside air temperature. As a result, since oil forming and the like can be reliably prevented, shortage of lubricating oil in the compressor (1) can be reliably prevented. Further, since the capacity of the compressor (1) does not increase at the time of the oil recovery, comfortable room temperature control can be performed. Also, since the time of oil recovery is determined by the air flow rate (L tap) of the outdoor fan (3b), the air flow rate of the outdoor fan (3b) is controlled by the external heat exchange temperature Tc, so that a simple logic Thus, the oil recovery operation can be controlled. Further, since the on-off valve (SV) is opened at the time of oil recovery, the high-pressure gas refrigerant in the receiver (4) can be bypassed to the low-pressure side, so that an abnormal increase in the high-pressure can be prevented. As a result, it is possible to prevent an abnormal stop or the like beforehand and improve the operation controllability. Also,
Because the cooling return means (17) outputs a return signal by the end timer (T2) and ends the oil recovery operation,
Since various end sensors are not required, the oil recovery operation can be controlled with a simple configuration.
【００３４】一方、上記実施例においては、室外ファン
(3b)の風量であるＬタップによって油回収運転の判断を
行うようにしたが、請求項１，３及び５に係る発明の実
施例として、低温判別手段(13)は、外熱交センサ(Thc)
の温度信号を受けて、冷房運転時における外熱交温度Tc
（凝縮圧力相当飽和温度）が予め設定された低温度にな
ると低温信号を出力するようにしてもよい。つまり、外
熱交温度Tcを直接取込み、該外熱交温度Tcが所定の低温
度になると、油回収実行手段(14)が油回収運転を実行す
ることになる。具体的に、該油回収実行手段(14)は、外
熱交温度Tcが２４℃より低下してこの低温度の状態が１
６分継続すると、油回収運転を実行すると共に、ファン
停止手段(15)が室外ファン(3b)を停止し、開閉弁制御手
段(16)が開閉弁(SV)を開動することになる。その際、前
実施例のように、外気温度Taが所定の低温度であるか否
かを判断する必要なく、外熱交温度Tcのみで油回収の判
断を行ってもよく、また、外気温度Taを判断の要件に入
れともよい。On the other hand, in the above embodiment, the outdoor fan
The oil recovery operation is determined by the L tap which is the air volume of (3b). However, as an embodiment of the invention according to claims 1, 3 and 5, the low-temperature determining means (13) includes an external heat exchange sensor ( Thc)
, The external heat exchange temperature Tc during the cooling operation
When (condensation pressure equivalent saturation temperature) becomes a preset low temperature, a low temperature signal may be output. That is, the external heat exchange temperature Tc is directly taken in, and when the external heat exchange temperature Tc becomes a predetermined low temperature, the oil recovery execution means (14) executes the oil recovery operation. Specifically, the oil recovery execution means (14) determines that the external heat exchange temperature Tc has dropped below 24 ° C.
When the operation continues for 6 minutes, the oil recovery operation is executed, the fan stopping means (15) stops the outdoor fan (3b), and the on-off valve control means (16) opens the on-off valve (SV). At that time, it is not necessary to determine whether or not the outside air temperature Ta is a predetermined low temperature as in the previous embodiment, and the determination of oil recovery may be made only by the outside heat exchange temperature Tc. Ta may be included in the judgment requirements.
【００３５】また、上記各実施例においては、冷房復帰
手段(17)が終了タイマ(T2)を備えて油回収運転を終了す
るようにしたが、図３に鎖線で示すように、請求項６に
係る発明の実施例として、上記冷房復帰手段(17)が高圧
検出手段である高圧センサ(HS)を備えるようにしてもよ
い。具体的に、該高圧センサ(HS)は、冷媒回路(9) にお
ける圧縮機(1) の吐出側に設けられて高圧圧力を検出し
ており、該高圧圧力が所定の所定の高圧（２４Kg／c
m2 ）になると、冷房復帰手段(17)が復帰信号を出力す
るように構成されている。この実施例によれば、高圧圧
力によって油回収運転を終了するようにしたために、該
油回収運転を必要時間行うことができるので、冷房運転
を迅速に再開することができる。また、本実施例におい
て、油回収実行手段(14)は、外気温度Ta及び室外ファン
(3b)の風量又は外熱交温度Tcで油回収運転を行うか否か
を判断する他、高圧センサ(HS)が検出する高圧圧力で油
回収運転を行うか否かを判断するようにしてもよく、例
えば、高圧圧力が１０Kg／cm2 より低下し、この低圧状
態が１６分継続すると油回収運転を開始し、該高圧圧力
が２４Kg／cm2 になると、油回収運転を終了するように
してもよい。Further, in each of the above embodiments, the cooling return means (17) is provided with the end timer (T2) to end the oil recovery operation, but as shown by a chain line in FIG. As an embodiment of the invention according to the above, the cooling return means (17) may include a high pressure sensor (HS) as a high pressure detecting means. Specifically, the high pressure sensor (HS) is provided on the discharge side of the compressor (1) in the refrigerant circuit (9) and detects a high pressure, and the high pressure sensor detects a high pressure (24 Kg / c
m 2 ), the cooling return means (17) is configured to output a return signal. According to this embodiment, since the oil recovery operation is terminated by the high pressure, the oil recovery operation can be performed for a required time, so that the cooling operation can be quickly restarted. Further, in the present embodiment, the oil recovery execution means (14) includes an outside air temperature Ta and an outdoor fan.
(3b) In addition to determining whether to perform the oil recovery operation at the air volume or the external heat exchange temperature Tc, as well as to determine whether to perform the oil recovery operation at the high pressure detected by the high pressure sensor (HS) For example, if the high pressure drops below 10 kg / cm 2 and this low pressure continues for 16 minutes, the oil recovery operation is started, and if the high pressure becomes 24 kg / cm 2 , the oil recovery operation is terminated. You may.
【００３６】また、上記各実施例において、圧縮機(1)
の容量については油回収運転の判断要素としていない
が、請求項４に係る発明の実施例として、油回収実行手
段(14)は、圧縮機(1) の容量が所定の低容量である状態
において、低温判別手段(13)が冷温信号を１６分継続し
て出力すると、油回収運転を実行するようにしてもよ
い。具体的に、例えば、圧縮機(1) の運転周波数が４０
Hz（周波数ステップＮが４）である状態において、外気
温度Taが３℃より低く、室外ファン(3b)がＬタップで１
６分継続すると、油回収運転を行うことになる。この実
施例によれば、圧縮機(1) が低容量運転時のみ油回収を
行うようにしたために、必要な油回収運転のみを行うこ
とができるので、冷房運転の快適性を向上させることが
できる。In each of the above embodiments, the compressor (1)
Although the capacity of the compressor (1) is not a determining factor of the oil recovery operation, as an embodiment of the invention according to claim 4, the oil recovery execution means (14) is provided in a state where the capacity of the compressor (1) is a predetermined low capacity. Alternatively, the oil recovery operation may be executed when the low-temperature determination means (13) outputs the cold-temperature signal continuously for 16 minutes. Specifically, for example, when the operating frequency of the compressor (1) is 40
Hz (frequency step N is 4), the outside air temperature Ta is lower than 3 ° C., and the outdoor fan (3b) is 1 L tap.
After 6 minutes, the oil recovery operation is performed. According to this embodiment, since the compressor (1) recovers oil only during low-capacity operation, only the necessary oil recovery operation can be performed, so that the comfort of the cooling operation can be improved. it can.
【００３７】尚、本各実施例においては、セパレートタ
イプの空気調和装置について説明したが、本発明は、各
種の空気調和装置に適用できることは勿論である。ま
た、上記各実施例においては、油回収運転時に開閉弁(S
V)を開動するようにしたが、請求項１及び２に係る発明
では、開閉弁(SV)を閉鎖したまま油回収運転を実行する
ようにしてもよい。In each of the embodiments, a separate type air conditioner has been described. However, the present invention can be applied to various types of air conditioners. In each of the above embodiments, the on-off valve (S
Although V) is opened, the oil recovery operation may be performed with the on-off valve (SV) closed in the inventions according to claims 1 and 2.
【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】本発明の構成を示すブロック図である。FIG. 2 is a block diagram showing a configuration of the present invention.
【図３】空気調和装置の冷媒配管系統を示す冷媒回路図
である。FIG. 3 is a refrigerant circuit diagram showing a refrigerant piping system of the air conditioner.
【図４】油回収運転の制御フロー図である。FIG. 4 is a control flowchart of an oil recovery operation.
【図５】外気温度と室内温度との関係における運転領域
の特性図である。FIG. 5 is a characteristic diagram of an operation region in a relationship between an outside air temperature and a room temperature.
【図６】油回収運転時のタイミング図である。FIG. 6 is a timing chart during an oil recovery operation.
【図７】室外ファンの停止時における高圧圧力の特性図
である。FIG. 7 is a characteristic diagram of the high pressure when the outdoor fan is stopped.
【図８】開閉弁の開動時における高圧圧力の特性図であ
る。FIG. 8 is a characteristic diagram of the high pressure when the on-off valve is opened.
【図９】室外ファンの停止した開閉弁の開動時における
高圧圧力の特性図である。FIG. 9 is a characteristic diagram of the high pressure when the open / close valve of the outdoor fan is stopped.
1 圧縮機 3 室外熱交換器（熱源側熱交換器） 3b 室外ファン（熱源側ファン） 4 レシーバ 4a ガス抜き路（バイパス路） 5 電動膨脹弁（膨脹機構） 6 室内熱交換器（利用側熱交換器） 9 冷媒回路 10 コントローラ 11 容量制御手段 12 ファン制御手段 13 低温判別手段 14 油回収実行手段 15 ファン停止手段 16 開閉弁制御手段 17 冷房復帰手段 Thc 外熱交センサ（飽和温度検出手段） Tha 外気温センサ（外気温度検出手段） SV 開閉弁 T2 終了タイマ HS 高圧センサ（高圧検出手段） 1 Compressor 3 Outdoor heat exchanger (heat source side heat exchanger) 3b Outdoor fan (heat source side fan) 4 Receiver 4a Gas vent path (bypass path) 5 Electric expansion valve (expansion mechanism) 6 Indoor heat exchanger (use side heat) 9) Refrigerant circuit 10 Controller 11 Capacity control means 12 Fan control means 13 Low temperature discrimination means 14 Oil recovery execution means 15 Fan stop means 16 Open / close valve control means 17 Cooling return means Thc External heat exchange sensor (saturation temperature detection means) Tha Outside air temperature sensor (outside air temperature detection means) SV open / close valve T2 end timer HS High pressure sensor (high pressure detection means)
フロントページの続き (72)発明者 四井 一志 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 (58)調査した分野(Int.Cl.6，ＤＢ名) F25B 1/00Continued on the front page (72) Inventor Kazushi Yotsui 1304 Kanaokacho, Sakai-shi, Osaka Daikin Industries, Ltd. Sakai Factory Kanaoka Factory (58) Fields investigated (Int. Cl. 6 , DB name) F25B 1/00
Claims (6)
された熱源側熱交換器(3) と、膨脹機構(5) と、利用側
熱交換器(6) とが順に接続されてなる冷媒回路(9) を備
えた空気調和装置において、 冷房運転時における凝縮圧力相当飽和温度を検出する飽
和温度検出手段(Thc)と、 該飽和温度検出手段(Thc) の温度信号を受けて、冷房運
転時における凝縮圧力相当飽和温度が予め設定された低
温度になると低温信号を出力する低温判別手段(13)と、 該低温判別手段(13)が所定時間継続して低温信号を出力
すると油回収信号を出力して油回収運転を実行する油回
収実行手段(14)と、 該油回収実行手段(14)が油回収信号を出力すると上記熱
源側ファン(3b)を停止するファン停止手段(15)と、 上記油回収実行手段(14)が油回収運転を開始した後、所
定状態になると該油回収実行手段(14)の油回収運転を終
了させると共に、ファン停止手段(15)の停止制御を終了
させる復帰信号を出力する冷房復帰手段(17)とを備えて
いることを特徴とする空気調和装置の油回収運転制御装
置。1. A compressor (1), a heat source side heat exchanger (3) provided with a heat source side fan (3b), an expansion mechanism (5), and a use side heat exchanger (6) are sequentially arranged. In an air conditioner equipped with a connected refrigerant circuit (9), a saturation temperature detecting means (Thc) for detecting a saturation temperature corresponding to a condensing pressure during a cooling operation, and a temperature signal of the saturation temperature detecting means (Thc). The low-temperature discriminating means (13) for outputting a low-temperature signal when the condensing pressure equivalent saturation temperature during the cooling operation becomes a preset low temperature, and the low-temperature discriminating means (13) continuously outputs the low-temperature signal for a predetermined time. An oil recovery execution means (14) that outputs an oil recovery signal to perform an oil recovery operation when output, and a fan that stops the heat source side fan (3b) when the oil recovery execution means (14) outputs an oil recovery signal After the stopping means (15) and the oil recovery executing means (14) start the oil recovery operation, when the oil recovery operation is in a predetermined state, the oil recovery is performed. An air conditioner, comprising: a cooling return unit (17) for outputting a return signal for terminating the stop control of the fan stop unit (15) while terminating the oil recovery operation of the running unit (14). Oil recovery operation control device.
(3b)が付設された熱源側熱交換器(3) と、膨脹機構(5)
と、利用側熱交換器(6) とが順に接続されてなる冷媒回
路(9) を備えた空気調和装置において、 外気温度を検出する外気温度検出手段(Tha) と、 上記熱源側ファン(3b)の風量を制御するファン制御手段
(12)と、 上記外気温度検出手段(Tha) の温度信号とファン制御手
段(12)の風量信号とを受けて、冷房運転時における外気
温度が予め設定された低温度で且つ熱源側ファン(3b)の
風量が予め設定された低風量になると低温信号を出力す
る低温判別手段(13)と、 該低温判別手段(13)が所定時間継続して低温信号を出力
すると油回収信号を出力して油回収運転を実行する油回
収実行手段(14)と、 該油回収実行手段(14)が油回収信号を出力すると上記熱
源側ファン(3b)を停止させる停止信号を上記ファン制御
手段(12)に出力するファン停止手段(15)と、 上記油回収実行手段(14)が油回収運転を開始した後、所
定状態になると該油回収実行手段(14)の油回収運転を終
了させると共に、ファン停止手段(15)の停止制御を終了
させる復帰信号を出力する冷房復帰手段(17)とを備えて
いることを特徴とする空気調和装置の油回収運転制御装
置。2. A compressor (1) and a heat source-side fan having a variable air volume.
Heat source side heat exchanger (3) equipped with (3b) and expansion mechanism (5)
And an air conditioner provided with a refrigerant circuit (9) in which a use side heat exchanger (6) is connected in order, an outside air temperature detecting means (Tha) for detecting an outside air temperature, and the heat source side fan (3b Fan control means for controlling the air volume
(12), receiving the temperature signal of the outside air temperature detection means (Tha) and the airflow signal of the fan control means (12), the outside air temperature during the cooling operation is a preset low temperature and the heat source side fan ( When the air volume of 3b) becomes a preset low air volume, a low-temperature discriminating means (13) for outputting a low-temperature signal, and when the low-temperature discriminating means (13) continuously outputs a low-temperature signal for a predetermined time, outputs an oil recovery signal. Oil recovery executing means (14) for executing an oil recovery operation, and a stop signal for stopping the heat source side fan (3b) when the oil recovery executing means (14) outputs an oil recovery signal. After the oil recovery execution means (14) starts the oil recovery operation, the oil recovery execution means (14) terminates the oil recovery operation of the oil recovery execution means (14). Cooling return means (17) for outputting a return signal for terminating the stop control of the fan stop means (15). Oil recovery operation control device for air conditioner, characterized by that.
回収運転制御装置において、冷媒回路(9) の液ラインに
はレシーバ(4) が設けられると共に、該レシーバ(4) と
冷媒回路(9) との間には、開閉弁(SV)を備えて上記レシ
ーバ(4) 内のガス冷媒を冷媒回路(9) の低圧側にバイパ
スするバイパス路(4a)が設けれられる一方、 油回収実行手段(14)が油回収信号を出力すると上記開閉
弁(SV)を開動させる開閉弁制御手段(16)が設けられ、 冷房復帰手段(17)は、油回収実行手段(14)が油回収運転
を開始した後、所定状態になると該油回収実行手段(14)
の油回収運転及びファン停止手段(15)の停止制御を終了
させると共に、上記開閉弁制御手段(16)が開閉弁(SV)を
閉動させる復帰信号を出力するように構成されているこ
とを特徴とする空気調和装置の油回収運転制御装置。3. The oil recovery operation control device for an air conditioner according to claim 1, wherein a receiver (4) is provided in a liquid line of the refrigerant circuit (9), and the receiver (4) and the refrigerant circuit are provided. A bypass passage (4a) provided with an on-off valve (SV) for bypassing the gas refrigerant in the receiver (4) to the low pressure side of the refrigerant circuit (9) is provided between On-off valve control means (16) for opening the on-off valve (SV) when the recovery execution means (14) outputs an oil recovery signal is provided.The cooling return means (17) is provided with oil recovery execution means (14). After the recovery operation is started, when a predetermined state is reached, the oil recovery execution means (14)
Oil recovery operation and stop control of the fan stop means (15), and the open / close valve control means (16) is configured to output a return signal for closing the open / close valve (SV). Characteristic oil recovery operation control device for air conditioners.
の油回収運転制御装置において、圧縮機(1) の容量を制
御する容量制御手段(11)が設けられる一方、 油回収実行手段(14)は、該容量制御手段(11)が所定の低
容量信号を出力している状態において低温判別手段(13)
が所定時間継続して低温信号を出力すると油回収信号を
出力して油回収運転を実行するように構成されているこ
とを特徴とする空気調和装置の油回収運転制御装置。4. The oil recovery operation control device for an air conditioner according to claim 1, further comprising a capacity control means (11) for controlling a capacity of the compressor (1), and an oil recovery execution means. (14) is a low-temperature determination means (13) while the capacity control means (11) is outputting a predetermined low capacity signal.
Is configured to output an oil recovery signal and execute an oil recovery operation when a low temperature signal is continuously output for a predetermined time.
気調和装置の油回収運転制御装置において、冷房復帰手
段(17)は、タイマ(T2)が所定時間を計数すると復帰信号
を出力するように構成されていることを特徴とする空気
調和装置の油回収運転制御装置。5. The oil recovery operation control device for an air-conditioning apparatus according to claim 1, wherein the cooling return means (17) outputs a return signal when the timer (T2) counts a predetermined time. An oil recovery operation control device for an air conditioner, wherein the oil recovery operation control device is configured to:
気調和装置の油回収運転制御装置において、冷房復帰手
段(17)は、圧縮機(1) の吐出側の高圧圧力を検出する高
圧検出手段(HS)が所定の高圧信号を出力すると復帰信号
を出力するように構成されていることを特徴とする空気
調和装置の油回収運転制御装置。6. The oil recovery operation control device for an air conditioner according to claim 1, wherein the cooling return means (17) detects a high pressure on the discharge side of the compressor (1). An oil recovery operation control device for an air conditioner, wherein the high pressure detection means (HS) outputs a return signal when a predetermined high voltage signal is output.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22754492A JP2765391B2 (en) | 1992-08-26 | 1992-08-26 | Oil recovery operation control device for air conditioner |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22754492A JP2765391B2 (en) | 1992-08-26 | 1992-08-26 | Oil recovery operation control device for air conditioner |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0674580A JPH0674580A (en) | 1994-03-15 |
| JP2765391B2 true JP2765391B2 (en) | 1998-06-11 |
Family
ID=16862566
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22754492A Expired - Lifetime JP2765391B2 (en) | 1992-08-26 | 1992-08-26 | Oil recovery operation control device for air conditioner |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2765391B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104180563A (en) * | 2013-05-27 | 2014-12-03 | 珠海格力电器股份有限公司 | Oil return method for heating of multi-split air conditioning system |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104764168A (en) * | 2015-04-21 | 2015-07-08 | 广东志高空调有限公司 | Method and device for improving oil return efficiency of household variable frequency air conditioner after low-frequency running |
| WO2017022076A1 (en) * | 2015-08-04 | 2017-02-09 | 三菱電機株式会社 | Refrigeration apparatus, and method of operating refrigeration apparatus |
-
1992
- 1992-08-26 JP JP22754492A patent/JP2765391B2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104180563A (en) * | 2013-05-27 | 2014-12-03 | 珠海格力电器股份有限公司 | Oil return method for heating of multi-split air conditioning system |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0674580A (en) | 1994-03-15 |
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