JP2014119154A

JP2014119154A - Air conditioner

Info

Publication number: JP2014119154A
Application number: JP2012273186A
Authority: JP
Inventors: Noi ASAJI; 野衣浅地
Original assignee: Sharp Corp
Current assignee: Sharp Corp
Priority date: 2012-12-14
Filing date: 2012-12-14
Publication date: 2014-06-30

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioner which can vary the amount of a refrigerant circulating in a refrigerant circuit so as to increase operation efficiency and has high safety even if stopping operating owing to a sudden power failure during operation.SOLUTION: There is provided an air conditioner in which a refrigerant amount control part 10 provided in parallel with a throttle device 5 constituting a refrigerant circuit includes a receiver 13 which reserves a refrigerant, a first connection pipe 14 connecting the receiver 13 to piping 11 and a second connection pipe 15 connecting the receiver 13 to piping 12, and a first flow rate control device 16 and a second flow rate control device 17 interposed in the first connection pipe 14 and a second connection pipe 15 and adjusting flow rates of the refrigerant. At least one of the first flow rate control device 16 and second flow rate control device 17 has a structure which is not fully opened.

Description

本発明は、冷媒回路を循環する冷媒量を調整可能な空気調和機に関する。 The present invention relates to an air conditioner capable of adjusting the amount of refrigerant circulating in a refrigerant circuit.

現在の空気調和機のほとんどは、冷房と暖房が切り替えられるように冷媒回路が構成されている。また、冷媒回路に必要な冷媒量は、凝縮器の大きさによって大きく変化するところ、一般的な空気調和機においては、冷媒回路を構成する室内熱交換器と室外熱交換器とで冷媒流路の容積が異なる。したがって、冷房運転時と暖房運転時とで、冷媒回路に必要とされる冷媒量が大きく変化する。また、同じ運転モードであっても、圧縮機の回転数が高い場合と低い場合とで冷媒回路に必要とされる冷媒量は変化する。 Most current air conditioners have a refrigerant circuit configured to switch between cooling and heating. Also, the amount of refrigerant required for the refrigerant circuit varies greatly depending on the size of the condenser. In a general air conditioner, the refrigerant flow path between the indoor heat exchanger and the outdoor heat exchanger that constitute the refrigerant circuit The volume of is different. Therefore, the amount of refrigerant required for the refrigerant circuit varies greatly between the cooling operation and the heating operation. Even in the same operation mode, the amount of refrigerant required for the refrigerant circuit varies depending on whether the rotation speed of the compressor is high or low.

上記課題に対して、特許文献１には、少なくとも１つの冷媒ラインによって冷媒回路と流通連通して接続される冷媒貯蔵装置と、少なくとも１つの冷媒ラインに配された冷媒流制御装置とを備え、冷媒流制御装置は冷媒が冷媒ラインを通流する開位置と、冷媒ラインを通る冷媒の流れを遮断する閉位置とを有する冷媒蒸気圧縮システムが記載されている。 In response to the above problem, Patent Document 1 includes a refrigerant storage device connected in flow communication with the refrigerant circuit by at least one refrigerant line, and a refrigerant flow control device arranged in at least one refrigerant line. The refrigerant flow control device is described as a refrigerant vapor compression system having an open position where the refrigerant flows through the refrigerant line and a closed position where the flow of the refrigerant passing through the refrigerant line is blocked.

特開２０１１−５２１１９４号公報JP 2011-521194 A

しかしながら、特許文献１では、必要冷媒量を調整するときのみ冷媒流制御装置を開位置にする制御を行っていることから、冷房運転や暖房運転などの空気調和機運転中に停電等で空気調和機へ電源の供給が途絶えることが発生したときは、冷媒貯蔵装置に冷媒が密封される可能性がある。したがって、冷媒貯蔵装置に冷媒が満たされた状態で密封され、その状態が炎天下で長時間続いた場合には、冷媒貯蔵装置内の冷媒が膨張（液膨張や液冷媒のガス化）することにより非常に高い圧力がかかることになる。冷媒流制御装置に過負荷がかかって故障したり、レシーバから冷媒回路の外に冷媒が漏れるおそれがあり、空気調和機の信頼性が悪くなる。 However, in Patent Document 1, since the refrigerant flow control device is controlled to be in the open position only when the required refrigerant amount is adjusted, air conditioning is performed due to a power failure or the like during air conditioner operations such as cooling operation or heating operation. When supply of power to the machine stops, the refrigerant may be sealed in the refrigerant storage device. Therefore, when the refrigerant storage device is sealed in a state where the refrigerant is filled and the state continues for a long time under the hot sun, the refrigerant in the refrigerant storage device expands (liquid expansion or liquid refrigerant gasification). Very high pressure will be applied. There is a possibility that the refrigerant flow control device is overloaded and breaks down, or the refrigerant leaks out of the refrigerant circuit from the receiver, and the reliability of the air conditioner deteriorates.

そこで、本発明においては、上記に鑑み、運転効率を高めるために冷媒回路を循環する冷媒量を変更可能で、空気調和機の運転中に急に停電等が発生して空気調和機へ電源の供給が途絶えることにより空気調和機の運転が停止した場合でも信頼性の高い空気調和機を提供することを目的とする。 Therefore, in the present invention, in view of the above, it is possible to change the amount of refrigerant circulating in the refrigerant circuit in order to improve the operation efficiency, and a power failure or the like suddenly occurs during the operation of the air conditioner, An object of the present invention is to provide a highly reliable air conditioner even when the operation of the air conditioner is stopped due to supply interruption.

上記目的を達成するために、本発明では、圧縮機、凝縮器、絞り装置および蒸発器が配管により順次接続されて冷媒が流れる冷媒回路が構成され、前記冷媒回路を流れる冷媒の量を調整する冷媒量調整部が前記絞り装置と並列に設けられ、前記冷媒量調整部は、前記絞り装置前後の高圧側配管から低圧側配管に流れる冷媒の圧力を利用して冷媒を溜めるレシーバと、前記レシーバと前記高圧側配管とを連結する高圧側連結管及び前記レシーバと前記低圧側配管とを連結する低圧側連結管と、前記高圧側連結管及び低圧側連結管にそれぞれ介装された、冷媒の流量を調整する高圧側流量調整装置及び低圧側流量調整装置とを備えた空気調和機であって、前記高圧側流量調整装置及び低圧側流量調整装置の開度を制御する制御装置が設けられ、前記制御装置は、前記高圧側流量調整装置及び低圧側流量調整装置のうちの少なくとも一方を全閉しないように開度調整することを特徴とする。 In order to achieve the above object, in the present invention, a compressor, a condenser, a throttling device, and an evaporator are sequentially connected by a pipe to form a refrigerant circuit through which refrigerant flows, and the amount of refrigerant flowing through the refrigerant circuit is adjusted. A refrigerant amount adjustment unit is provided in parallel with the expansion device, and the refrigerant amount adjustment unit stores a refrigerant using a pressure of the refrigerant flowing from the high-pressure side pipe before and after the expansion device to the low-pressure side pipe, and the receiver And a high-pressure side connecting pipe that connects the high-pressure side pipe, a low-pressure side connecting pipe that connects the receiver and the low-pressure side pipe, and a refrigerant that is interposed in the high-pressure side connecting pipe and the low-pressure side connecting pipe, respectively. An air conditioner including a high pressure side flow rate adjustment device and a low pressure side flow rate adjustment device for adjusting a flow rate, and a control device for controlling the opening degree of the high pressure side flow rate adjustment device and the low pressure side flow rate adjustment device is provided, Previous Controller, characterized by the opening adjustment so as not to fully close at least one of the high-pressure side flow control device and the low-flow control device.

上記構成によれば、制御装置は、空気調和機運転中は、高圧側流量調整装置及び低圧側流量調整装置のうちの少なくとも一方を全閉しないように開度調整するため、たとえ、冷房運転や暖房運転などの空気調和機の運転中にレシーバ内いっぱいの冷媒が収容された状態で停電などにより、空気調和機へ電源の供給が途絶えて流量調整装置の動作が停止したとしても、レシーバ内に溜まった冷媒は全閉しない流量調整装置、すなわち、開放状態の流量調整装置を通って冷媒回路に戻ることになる。従って、レシーバの容量を必要以上に大きくすることなく、安全性の高い空気調和機を得ることができる。 According to the above configuration, the controller adjusts the opening degree so that at least one of the high pressure side flow rate adjustment device and the low pressure side flow rate adjustment device is not fully closed during the air conditioner operation. Even if the supply of power to the air conditioner is interrupted due to a power failure while the receiver is full of refrigerant while the air conditioner is in operation, such as heating operation, The accumulated refrigerant returns to the refrigerant circuit through a flow rate adjustment device that does not fully close, that is, an open flow rate adjustment device. Therefore, a highly safe air conditioner can be obtained without increasing the capacity of the receiver more than necessary.

全閉しない流量調整装置は低圧側流量調整装置としてもよい。すなわち、空気調和機が冷暖房運転可能に構成されている場合は、各運転モードにおいて、低圧側流量調整装置を全閉しないように開度調整すればよい。これにより、停電により急に圧縮機が停止した時に、冷媒の圧力差によってレシーバに溜まった冷媒をよりスムーズに冷媒回路に放出することができる。 The flow rate adjusting device that is not fully closed may be a low pressure side flow rate adjusting device. That is, when the air conditioner is configured to be capable of cooling and heating, the opening degree may be adjusted so as not to fully close the low-pressure flow rate adjusting device in each operation mode. Thereby, when the compressor is suddenly stopped due to a power failure, the refrigerant accumulated in the receiver due to the refrigerant pressure difference can be discharged more smoothly into the refrigerant circuit.

制御装置は、入力された設定温度、室温センサによって検出された室温及び外気温センサによって検出された外気温に応じて、予め記憶された運転条件データを基に、圧縮機の回転数、絞り装置の開度、高圧側流量調整装置の開度及び低圧側流量調整装置の開度を制御するようにしてもよい。 The control device is configured to input the set temperature, the room temperature detected by the room temperature sensor, and the outside air temperature detected by the outside air temperature sensor, based on the operation condition data stored in advance, the compressor rotation speed, the throttle device , The opening of the high pressure side flow control device and the opening of the low pressure flow control device may be controlled.

具体的に、先ず、設定温度、室温及び外気温に応じて、最適となる圧縮機の回転数及び絞り装置の開度が決定される。そして、少なくとも一方の流量調整装置を全閉しないという条件下で最適冷媒量となるように、前記高圧側流量調整装置及び低圧側流量調整装置の開度を求める。このようにして得た運転条件データは制御装置のメモリに記憶され、入力された設定温度、室温及び外気温に応じて、運転条件データを基に圧縮機の回転数、絞り装置の開度、両流量調整装置の開度が制御される。 Specifically, first, the optimum rotation speed of the compressor and the opening of the expansion device are determined according to the set temperature, room temperature, and outside air temperature. Then, the opening degrees of the high-pressure side flow control device and the low-pressure side flow control device are obtained so that the optimum refrigerant amount is obtained under the condition that at least one of the flow control devices is not fully closed. The operating condition data obtained in this way is stored in the memory of the control device, and according to the input set temperature, room temperature and outside air temperature, based on the operating condition data, the rotational speed of the compressor, the opening degree of the expansion device, The opening degree of both flow rate adjusting devices is controlled.

なお、ここで最適冷媒量とは、冷媒回路に封入された冷媒量からレシーバ内に貯留される冷媒量を引いた、実際に冷媒回路を循環する冷媒量（循環冷媒量）のうち、「空調能力」／「消費電力」で表わされるＣＯＰ（成績係数）が最大となる冷媒量を意味する。 Here, the optimum refrigerant amount is the “air conditioning” of the refrigerant amount (circulating refrigerant amount) that actually circulates in the refrigerant circuit obtained by subtracting the refrigerant amount stored in the receiver from the refrigerant amount enclosed in the refrigerant circuit. It means the amount of refrigerant that maximizes the COP (coefficient of performance) represented by “capacity” / “power consumption”.

制御装置が高圧側流量調整装置の開度及び低圧側流量調整装置の開度を制御することで調整した冷媒量と、実際に冷媒回路を循環する冷媒量との間にずれが生じる場合がある。そこで、制御装置によって調整された冷媒量が最適冷媒量からずれていないかチェックするようにしてもよい。 There may be a difference between the refrigerant amount adjusted by the control device controlling the opening degree of the high-pressure side flow rate adjustment device and the low-pressure side flow rate adjustment device and the refrigerant amount actually circulating in the refrigerant circuit. . Therefore, it may be checked whether the refrigerant amount adjusted by the control device is deviated from the optimum refrigerant amount.

具体的には、制御装置は、運転状態が安定したと判断したときに、凝縮器の出口温度及び蒸発器の出口温度に応じて、高圧側流量調整装置の開度及び低圧側流量調整装置の開度を調整する。すなわち、循環する冷媒量が最適冷媒量で一定で、環境条件、圧縮機の回転数及び絞り装置の開度が一定の冷媒回路では、過冷却度及び過熱度の値が決まる。これらの値が、最適冷媒量における過冷却度の基準値（基準過冷却度）及び過熱度の基準値（基準過熱度）となる。一方、実際の過冷却度は凝縮器出口の温度を測定することにより、また、実際の過熱度は蒸発器出口の温度を測定することによりそれぞれ知ることができる。 Specifically, when the control device determines that the operation state is stable, the opening degree of the high-pressure side flow control device and the low-pressure side flow control device according to the outlet temperature of the condenser and the outlet temperature of the evaporator. Adjust the opening. That is, the value of the degree of supercooling and the degree of superheat is determined in a refrigerant circuit in which the amount of refrigerant circulating is constant at the optimum amount of refrigerant and the environmental conditions, the rotation speed of the compressor, and the opening of the expansion device are constant. These values serve as a reference value for the degree of supercooling (reference degree of supercooling) and a reference value for the degree of superheating (reference degree of superheat) in the optimum refrigerant amount. On the other hand, the actual degree of supercooling can be determined by measuring the temperature at the outlet of the condenser, and the actual degree of superheat can be determined by measuring the temperature at the outlet of the evaporator.

従って、過冷却度の基準値と実測値との差、及び、過熱度の基準値と実測値との差と、これらの温度差を解消するために必要な高圧側流量調整装置の開度の調整値及び低圧側流量調整装置の開度の調整値とを予め実験で求め、そのデータを制御装置に記憶しておく。これにより、制御装置は、凝縮器出口の実際の温度及び蒸発器出口の実際の温度に応じて、制御装置が実験で得たデータを基にして高圧側流量調整装置の開度及び低圧側流量調整装置の開度の調整を行うことにより、最適冷媒量に正確に調整することができる。 Therefore, the difference between the reference value of the supercooling degree and the actual measurement value, the difference between the reference value of the superheat degree and the actual measurement value, and the opening degree of the high pressure side flow rate adjustment device necessary to eliminate these temperature differences. The adjustment value and the adjustment value of the opening degree of the low pressure side flow rate adjustment device are obtained in advance by experiments, and the data is stored in the control device. In this way, the control device determines the opening degree and the low-pressure side flow rate of the high-pressure side flow control device based on the data obtained by the control device in the experiment according to the actual temperature at the condenser outlet and the actual temperature at the evaporator outlet. By adjusting the opening of the adjusting device, it is possible to accurately adjust to the optimum refrigerant amount.

高圧側流量調整装置及び低圧側流量調整装置のうち、少なくとも一方を全閉しない構造の流量調整装置としてもよい。これにより、確実に高圧側流量調整装置及び低圧側流量調整装置のうちの少なくとも一方を全閉しないように開度調整することができる。 It is good also as a flow control device of the structure which does not fully close at least one among a high pressure side flow control device and a low pressure side flow control device. Thereby, the opening degree can be adjusted so that at least one of the high-pressure side flow rate adjusting device and the low-pressure side flow rate adjusting device is not fully closed.

以上のとおり、本発明の空気調和機は、絞り装置に対して並列に設けられた冷媒量調整部において、レシーバに接続した高圧側連結管及び低圧側連結管にそれぞれ高圧側流量調整装置及び低圧側流量調整装置を介装し、高圧側流量調整装置及び低圧側流量調整装置の開度を制御する制御装置を設け、制御装置によって高圧側流量調整装置及び低圧側流量調整装置のうち、少なくとも一方を全閉しないように開度調整したため、停電等で空気調和機へ電源の供給が途絶えることにより急に空気調和機の運転が停止してもレシーバから冷媒を冷媒回路に戻すことが可能である。 As described above, the air conditioner of the present invention includes a high-pressure side flow control device and a low-pressure device connected to the high-pressure side connecting tube and the low-pressure side connecting tube connected to the receiver, respectively, in the refrigerant amount adjusting unit provided in parallel with the expansion device. A control device for controlling the opening degree of the high pressure side flow rate adjustment device and the low pressure side flow rate adjustment device is provided, and at least one of the high pressure side flow rate adjustment device and the low pressure side flow rate adjustment device is provided by the control device. Since the opening is adjusted so as not to be fully closed, it is possible to return the refrigerant from the receiver to the refrigerant circuit even if the operation of the air conditioner stops suddenly due to the interruption of the power supply to the air conditioner due to a power failure etc. .

本発明の空気調和機の冷媒回路を示す図The figure which shows the refrigerant circuit of the air conditioner of this invention 本発明の空気調和機の制御ブロック図Control block diagram of the air conditioner of the present invention サーモオフ時の空調運転のフローチャート図Flow chart of air conditioning operation when the thermo is off サーモオフ時の流量調整装置の制御フローチャート図Control flow chart of flow rate adjusting device when thermo is off 冷媒調整部の別の態様を示す模式図The schematic diagram which shows another aspect of a refrigerant | coolant adjustment part.

以下、図面に基づいて本発明の実施の形態を説明する。図１は、本発明に係る空気調和機の実施形態を示す冷媒回路図である。図示のごとく、本実施形態の空気調和機は、１台の室外機１に１台の室内機２が接続されたシングル型空気調和機であり、室外機１に収容される圧縮機３、室外熱交換器４及び絞り装置５をこの順に冷媒配管で直列に接続し、さらに絞り装置５から二方弁６を介して、室内機２に収容される室内熱交換器７を配管接続し、室内熱交換器７から三方弁８を介して、再び室外の圧縮機３に配管接続して冷媒回路を構成している。 Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a refrigerant circuit diagram showing an embodiment of an air conditioner according to the present invention. As illustrated, the air conditioner of the present embodiment is a single-type air conditioner in which one indoor unit 2 is connected to one outdoor unit 1, and includes a compressor 3 housed in the outdoor unit 1, an outdoor unit The heat exchanger 4 and the expansion device 5 are connected in series in this order by refrigerant piping, and further, the indoor heat exchanger 7 accommodated in the indoor unit 2 is connected by piping from the expansion device 5 through the two-way valve 6, The refrigerant circuit is configured by connecting the pipe from the heat exchanger 7 to the outdoor compressor 3 through the three-way valve 8 again.

圧縮機３は、切換弁である四方弁９を介して冷媒回路に接続されており、四方弁９を切り換えることにより、室外熱交換器４側、又は、室内熱交換器７側のいずれの方向へも圧縮した冷媒を送出可能な構成とされている。この四方弁９の切り換えにより、室外熱交換器４と室内熱交換器７とが、凝縮器又は蒸発器として使用される。 The compressor 3 is connected to the refrigerant circuit via a four-way valve 9 that is a switching valve. By switching the four-way valve 9, either direction of the outdoor heat exchanger 4 side or the indoor heat exchanger 7 side is selected. The compressed refrigerant can be sent out. By switching the four-way valve 9, the outdoor heat exchanger 4 and the indoor heat exchanger 7 are used as a condenser or an evaporator.

具体的に、図１では、圧縮機３から吐出される高温の冷媒が、図示する実線矢印方向に流通され、凝縮器としての室外熱交換器４、絞り装置５を経て蒸発器としての室内熱交換器７に流入されることによって冷房運転が実現される。また、圧縮機３から吐出される冷媒が、図示する破線矢印方向に流通され、凝縮器としての室内熱交換器７、絞り装置５を経て蒸発器としての室外熱交換器４に流入されることによって暖房運転が実現される。 Specifically, in FIG. 1, the high-temperature refrigerant discharged from the compressor 3 is circulated in the direction indicated by the solid line in the figure, and passes through the outdoor heat exchanger 4 as a condenser and the expansion device 5 and the indoor heat as an evaporator. Cooling operation is realized by flowing into the exchanger 7. In addition, the refrigerant discharged from the compressor 3 is circulated in the direction of the broken arrow shown in the figure, and flows into the outdoor heat exchanger 4 as an evaporator via the indoor heat exchanger 7 as a condenser and the expansion device 5. By this, heating operation is realized.

本発明では、冷媒回路を流れる冷媒の量を調整する冷媒量調整部１０が絞り装置５と並列に接続されている。冷媒量調整部１０は、絞り装置５前後の配管１１、１２に流れる冷媒の圧力を利用して冷媒を溜めるレシーバ１３と、レシーバ１３と配管１１とを連結する第一連結管１４及びレシーバ１３と配管１２とを連結する第二連結管１５と、第一連結管１４に介装される第一流量調整装置１６と、第二連結管１５に介装される第二流量調整装置１７とを備えている。 In the present invention, the refrigerant amount adjusting unit 10 that adjusts the amount of refrigerant flowing through the refrigerant circuit is connected in parallel with the expansion device 5. The refrigerant amount adjusting unit 10 includes a receiver 13 that accumulates refrigerant using the pressure of the refrigerant flowing through the pipes 11 and 12 before and after the expansion device 5, a first connection pipe 14 that connects the receiver 13 and the pipe 11, and the receiver 13. A second connecting pipe 15 that connects the pipe 12, a first flow rate adjusting device 16 that is interposed in the first connecting pipe 14, and a second flow rate adjusting device 17 that is interposed in the second connecting pipe 15 are provided. ing.

レシーバ１３の大きさとして、空調運転によって変動し得る最適冷媒量の最大量と最小量の容積差をそのままレシーバの内容積としてもよいが、それよりもレシーバ１３を少し大型化することで、レシーバ１３内に貯留されている液冷媒が液膨張やガス化した際に、圧力が逃げるスペースが存在するため、信頼性が向上する。従って、運転条件に応じた最適冷媒量の変更による運転効率の向上を図るためには、最適冷媒量の最大量と最小量の容積差を基準としてその１倍以上の容積に設定すればよりよい。 As the size of the receiver 13, the volume difference between the maximum amount and the minimum amount of the optimum refrigerant amount that can fluctuate depending on the air conditioning operation may be used as the internal volume of the receiver as it is. When the liquid refrigerant stored in 13 is expanded or gasified, there is a space for pressure to escape, so the reliability is improved. Therefore, in order to improve the operation efficiency by changing the optimum refrigerant amount according to the operation conditions, it is better to set the volume to at least one time based on the volume difference between the maximum amount and the minimum amount of the optimum refrigerant amount. .

冷媒回路において、絞り装置５の冷媒の流れ方向上流側は高圧となり、絞り装置５の冷媒の流れ方向下流側は低圧となる。すなわち、冷房運転時には、配管１１が高圧側配管で配管１２が低圧側配管に、第一連結管１４が高圧側連結管で第二連結管１５が低圧側連結管に、第一流量調整装置１６が高圧側流量調整装置で第二流量調整装置１７が低圧側流量調整装置になる。一方、暖房運転時は、配管１２が高圧側配管で配管１１が低圧側配管に、第二連結管１５が高圧側連結管で第一連結管１４が低圧側連結管に、第二流量調整装置１７が高圧側流量調整装置で第一流量調整装置１６が低圧側流量調整装置になる。 In the refrigerant circuit, the upstream side in the refrigerant flow direction of the expansion device 5 has a high pressure, and the downstream side in the refrigerant flow direction of the expansion device 5 has a low pressure. That is, during the cooling operation, the pipe 11 is a high-pressure side pipe, the pipe 12 is a low-pressure side pipe, the first connection pipe 14 is a high-pressure side connection pipe, the second connection pipe 15 is a low-pressure side connection pipe, and the first flow rate adjustment device 16. Is the high pressure side flow control device, and the second flow control device 17 is the low pressure side flow control device. On the other hand, during the heating operation, the pipe 12 is the high pressure side pipe, the pipe 11 is the low pressure side pipe, the second connecting pipe 15 is the high pressure side connecting pipe, the first connecting pipe 14 is the low pressure side connecting pipe, and the second flow rate adjusting device. Reference numeral 17 denotes a high-pressure side flow control device, and the first flow control device 16 serves as a low-pressure side flow control device.

図２に示すように、空気調和機は、冷凍回路の運転を制御して、空調運転を制御する制御装置２０を備えている。空気調和機には、室外熱交換器４の出口温度を検出する温度センサ２１、室内熱交換器７の出口温度を検出する温度センサ２２、圧縮機３から吐出された冷媒の吐出温度を検出する吐出温度センサ２３、室温センサ２４、外気温センサ２５が設けられる。 As shown in FIG. 2, the air conditioner includes a control device 20 that controls the operation of the refrigeration circuit and controls the air conditioning operation. In the air conditioner, a temperature sensor 21 that detects an outlet temperature of the outdoor heat exchanger 4, a temperature sensor 22 that detects an outlet temperature of the indoor heat exchanger 7, and a discharge temperature of the refrigerant discharged from the compressor 3 are detected. A discharge temperature sensor 23, a room temperature sensor 24, and an outside air temperature sensor 25 are provided.

制御装置２０は、ＣＰＵ、メモリ等を備えたマイコンから構成され、所望の空調運転に応じて、これらの温度センサの出力や、リモコン、本体の操作スイッチの操作信号等に基づき、圧縮機３、送風機２６、絞り装置５、第一流量調整装置１６及び第二流量調整装置１７の動作を制御して、冷媒回路の運転を制御する。 The control device 20 is composed of a microcomputer equipped with a CPU, a memory, and the like. Based on outputs of these temperature sensors, remote controllers, operation signals of operation switches of the main body, and the like according to a desired air conditioning operation, the compressor 3, The operation of the refrigerant circuit is controlled by controlling the operations of the blower 26, the expansion device 5, the first flow rate adjusting device 16, and the second flow rate adjusting device 17.

なお、制御装置２０は、室内機２に設けられた室内制御部と、室外機１に設けられた室外制御部とから構成される。室内制御部と室外制御部とは互いに通信可能に接続され、両者が連携して室内機２および室外機１の動作を制御する。 The control device 20 includes an indoor control unit provided in the indoor unit 2 and an outdoor control unit provided in the outdoor unit 1. The indoor control unit and the outdoor control unit are connected so as to be communicable with each other, and both cooperate to control operations of the indoor unit 2 and the outdoor unit 1.

空調運転が開始すると、制御装置２０は、設定温度と室温とに基づいて圧縮機３の目標回転数を設定し、目標回転数に応じて絞り装置５の開度を決める。制御装置２０は、決められた運転条件にしたがって、室温が設定温度になるように圧縮機３、絞り装置５、送風機２６などを制御する。 When the air conditioning operation starts, the control device 20 sets a target rotational speed of the compressor 3 based on the set temperature and room temperature, and determines the opening degree of the expansion device 5 according to the target rotational speed. The control device 20 controls the compressor 3, the expansion device 5, the blower 26, and the like so that the room temperature becomes the set temperature in accordance with the determined operating conditions.

そして、制御装置２０は、空調運転を開始して、圧縮機３の運転を開始すると、最適冷媒量となるように冷媒量調整制御を行う。冷媒回路に充填された冷媒の一部は、レシーバ１３に溜められ、残りの冷媒が冷媒回路を循環する。冷媒量調整制御では、空調運転の種類（冷房運転、暖房運転）、吐出温度、圧縮機の回転数、室温、外気温、設定温度などの運転状況に応じて、第一流量調整装置１６及び第二流量調整装置１７の開度が設定される。 And the control apparatus 20 will perform refrigerant | coolant amount adjustment control so that it may become the optimal refrigerant | coolant amount, if an air-conditioning driving | operation is started and the driving | operation of the compressor 3 is started. A part of the refrigerant filled in the refrigerant circuit is accumulated in the receiver 13, and the remaining refrigerant circulates in the refrigerant circuit. In the refrigerant amount adjustment control, the first flow rate adjusting device 16 and the first flow rate adjusting device 16 are controlled according to the operation conditions such as the type of air conditioning operation (cooling operation, heating operation), discharge temperature, compressor rotation speed, room temperature, outside air temperature, and set temperature. The opening degree of the two flow rate adjusting device 17 is set.

一般的に、室外熱交換器４の容量は室内熱交換器７の容量よりも大である。そのため、冷房運転時には、より多くの冷媒が必要となる。本実施形態においても、冷房定格運転時の最適冷媒量は暖房定格運転時の最適冷媒量よりも多くなるように設定される。ここで、定格運転とは、圧縮機の回転数を予め設定した一定値で駆動させる運転を意味する。圧縮機の回転数としては、最小回転数と最大回転数の間の運転効率が高く標準的な回転数が設定される。すなわち、冷房運転および除湿運転が最適冷媒量の多い空調運転、暖房運転が最適冷媒量の少ない空調運転とされる。 Generally, the capacity of the outdoor heat exchanger 4 is larger than the capacity of the indoor heat exchanger 7. Therefore, more refrigerant is required during the cooling operation. Also in the present embodiment, the optimum refrigerant amount during the cooling rated operation is set to be larger than the optimum refrigerant amount during the heating rated operation. Here, the rated operation means an operation in which the rotation speed of the compressor is driven at a preset constant value. As the rotation speed of the compressor, a standard rotation speed is set with high operation efficiency between the minimum rotation speed and the maximum rotation speed. That is, the cooling operation and the dehumidifying operation are the air conditioning operation with a large amount of the optimum refrigerant, and the heating operation is the air conditioning operation with a small amount of the optimum refrigerant.

制御装置２０は、冷媒量調整制御を行うとき、現在の運転状況に基づいて第一流量調整装置１６及び第二流量調整装置１７の開度を決め、決められた開度になるように第一流量調整装置１６及び第二流量調整装置１７を制御する。なお、運転状況に応じた第一流量調整装置１６及び第二流量調整装置１７の開度は、実験等により予め決められ、メモリに記憶されている。制御装置２０は、空調運転中、現在の運転状況に応じた第一流量調整装置１６及び第二流量調整装置１７の開度をメモリから読み出し、読み出した開度に応じて第一流量調整装置１６及び第二流量調整装置１７を動作させる。 When performing the refrigerant amount adjustment control, the control device 20 determines the opening amounts of the first flow rate adjustment device 16 and the second flow rate adjustment device 17 on the basis of the current operation state, and the first opening amount is set so as to be the determined opening amount. The flow rate adjusting device 16 and the second flow rate adjusting device 17 are controlled. In addition, the opening degree of the first flow rate adjusting device 16 and the second flow rate adjusting device 17 according to the operation state is determined in advance by experiments or the like and stored in the memory. During the air conditioning operation, the control device 20 reads the opening amounts of the first flow rate adjustment device 16 and the second flow rate adjustment device 17 according to the current operation status from the memory, and the first flow rate adjustment device 16 according to the read opening degree. And the second flow rate adjusting device 17 is operated.

絞り装置５は、冷媒の流量を調整する装置であり、本実施形態では膨張弁が用いられているが、これに限らず複数のキャピラリチューブを並べて、流路を切り替えるようにしてもよい。また、第一流量調整装置１６及び第二流量調整装置１７は、開閉することによって第一連結管１４及び第二連結管１５における冷媒の流れを制御する。 The expansion device 5 is a device that adjusts the flow rate of the refrigerant. In this embodiment, an expansion valve is used. However, the expansion device 5 is not limited thereto, and a plurality of capillary tubes may be arranged to switch the flow path. The first flow rate adjusting device 16 and the second flow rate adjusting device 17 control the flow of the refrigerant in the first connecting pipe 14 and the second connecting pipe 15 by opening and closing.

すなわち、第一流量調整装置１６及び第二流量調整装置１７は、レシーバ１３内の冷媒の圧力を調整するものであり、膨張弁、流量調整弁、ストップ弁などを用いる。本実施形態では、第一流量調整装置１６及び第二流量調整装置１７として、同型のニードルバルブを用い、全開位置を基準としてステッピングモータによって開度を正確に制御する構成とされる。 That is, the first flow rate adjusting device 16 and the second flow rate adjusting device 17 adjust the pressure of the refrigerant in the receiver 13, and use an expansion valve, a flow rate adjustment valve, a stop valve, and the like. In the present embodiment, the first flow rate adjusting device 16 and the second flow rate adjusting device 17 are configured to use the same type of needle valve and to accurately control the opening degree by the stepping motor with the fully open position as a reference.

冷媒量調整制御は、圧縮機３の運転が開始された時点から実行される。すなわち、リモコンから運転信号を受信したとき、あるいはタイマ予約による予約時間になったときなどの運転指示が入力されたとき、制御装置２０は、空調運転を開始して、圧縮機３を動作させる。このとき、制御装置２０は、運転状況に基づいて第一流量調整装置１６及び第二流量調整装置１７の開度をそれぞれ決める。この運転開始時に、運転状況として、空調運転の種類が確認される。制御装置２０は、リモコンからの運転信号あるいはタイマ予約情報に基づいて、開始される空調運転の種類を判別する。 The refrigerant amount adjustment control is executed from the time when the operation of the compressor 3 is started. That is, when an operation instruction is input such as when an operation signal is received from the remote controller or when a reservation time is reached due to timer reservation, the control device 20 starts the air conditioning operation and operates the compressor 3. At this time, the control device 20 determines the opening degrees of the first flow rate adjustment device 16 and the second flow rate adjustment device 17 based on the operation state. At the start of this operation, the type of air conditioning operation is confirmed as the operation status. The control device 20 determines the type of air conditioning operation to be started based on the operation signal from the remote controller or timer reservation information.

制御装置２０は、空調運転中に高圧側流量調整装置及び低圧側流量調整装置のうちの少なくとも一方を全閉しないように制御する。本実施形態では、少なくとも第一流量調整装置１６が全閉しないように制御される。すなわち、暖房定格運転時よりも冷房定格運転時の方が、最適冷媒量が多くなるように設定されるため、暖房運転モードにおいてレシーバ１３内は冷媒で満たされる。この状態で、急に停電等によって空気調和機へ電源の供給が途絶えることにより空気調和機が停止しても低圧側流量調整装置となる第一流量調整装置１６を全閉しないことで、冷媒の圧力差によってレシーバ１３内の冷媒をスムーズに冷媒回路に戻すことができる。 The control device 20 performs control so that at least one of the high pressure side flow rate adjustment device and the low pressure side flow rate adjustment device is not fully closed during the air conditioning operation. In the present embodiment, control is performed so that at least the first flow rate adjusting device 16 is not fully closed. That is, since the optimum refrigerant amount is set to be larger in the cooling rated operation than in the heating rated operation, the receiver 13 is filled with the refrigerant in the heating operation mode. In this state, even if the supply of power to the air conditioner suddenly stops due to a power failure or the like, even if the air conditioner stops, the first flow rate adjustment device 16 that is the low pressure side flow rate adjustment device is not fully closed, The refrigerant in the receiver 13 can be smoothly returned to the refrigerant circuit by the pressure difference.

なお、第二流量調整装置１７も全閉しないように制御してもよいことは勿論である。また、冷房定格運転時よりも暖房定格運転時の方が、最適冷媒量が多くなるように設定される場合は、第二流量調整装置１７を全閉しないように制御すればよい。
上記制御により、空調運転中はレシーバ１３内に冷媒を密封することができない。したがって、圧縮機３の駆動時には第一流量調整装置１６及び第二流量調整装置１７の開度を調整することでレシーバ１３内の冷媒量を調整することが必要とされる。 Of course, the second flow rate adjusting device 17 may be controlled not to be fully closed. Further, when the optimum refrigerant amount is set to be larger during the heating rated operation than during the cooling rated operation, the second flow rate adjusting device 17 may be controlled not to be fully closed.
With the above control, the refrigerant cannot be sealed in the receiver 13 during the air conditioning operation. Therefore, when the compressor 3 is driven, it is necessary to adjust the refrigerant amount in the receiver 13 by adjusting the opening degree of the first flow rate adjusting device 16 and the second flow rate adjusting device 17.

具体的に、制御装置２０は、設定温度、室温及び外気温に応じて、最適となる圧縮機の回転数及び絞り装置の開度を決定する。そして、少なくとも一方の流量調整装置を全閉しないという条件下で最適冷媒量となるように、第一流量調整装置１６及び第二流量調整装置１７の開度を実験等によって求める。 Specifically, the control device 20 determines the optimum rotation speed of the compressor and the opening degree of the expansion device in accordance with the set temperature, the room temperature, and the outside air temperature. Then, the opening amounts of the first flow rate adjustment device 16 and the second flow rate adjustment device 17 are obtained by experiments or the like so that the optimum refrigerant amount is obtained under the condition that at least one flow rate adjustment device is not fully closed.

このようにして得た運転条件データを制御装置２０のメモリに記憶する。制御装置２０は、空調運転中、現在の運転状況に応じた第一流量調整装置１６及び第二流量調整装置１７の開度をメモリから読み出し、読み出した開度に応じて第一流量調整装置１６及び第二流量調整装置１７を動作させる。 The operating condition data obtained in this way is stored in the memory of the control device 20. During the air conditioning operation, the control device 20 reads the opening amounts of the first flow rate adjustment device 16 and the second flow rate adjustment device 17 according to the current operation status from the memory, and the first flow rate adjustment device 16 according to the read opening degree. And the second flow rate adjusting device 17 is operated.

暖房運転モードを実行するときは、配管１２が高圧側配管となり、第二連結管１５が高圧側連結管に、第二流量調整装置１７が高圧側流量調整装置となる。そして、配管１１が低圧側配管となり、第一連結管１４が低圧側連結管に、第一流量調整装置１６が低圧側流量調整装置となる。 When the heating operation mode is executed, the pipe 12 is a high-pressure side pipe, the second connection pipe 15 is a high-pressure side connection pipe, and the second flow rate adjustment device 17 is a high-pressure side flow rate adjustment apparatus. The pipe 11 becomes a low-pressure side pipe, the first connecting pipe 14 becomes a low-pressure side connecting pipe, and the first flow rate adjusting device 16 becomes a low-pressure side flow rate adjusting apparatus.

このとき、高圧側流量調整装置である第二流量調整装置１７の開度を、低圧側流量調整装置である第一流量調整装置１６の開度よりも大きくする、あるいは、第二流量調整装置１７を開き、第一流量調整装置１６を閉じることで、レシーバ１３内に冷媒が溜まる。制御装置２０は、前記第一流量調整装置１６及び第二流量調整装置１７の開度の関係を維持しつつ、実験により求めた所定の開度とすることで、余剰の冷媒をレシーバ１３内に溜め、暖房定格運転時における最適冷媒量とすることができる。 At this time, the opening degree of the second flow rate adjusting device 17 that is the high pressure side flow rate adjusting device is made larger than the opening degree of the first flow rate adjusting device 16 that is the low pressure side flow rate adjusting device, or the second flow rate adjusting device 17. Is opened and the first flow rate adjusting device 16 is closed, whereby the refrigerant accumulates in the receiver 13. The control device 20 maintains the relationship between the opening amounts of the first flow rate adjustment device 16 and the second flow rate adjustment device 17 and sets the predetermined amount of opening obtained by experiments to allow surplus refrigerant to enter the receiver 13. It is possible to obtain the optimum refrigerant amount at the time of reservoir and heating rated operation.

一方、冷房運転モードを実行するときは、配管１１が高圧側配管となり、第一連結管１４が高圧側連結管に、第一流量調整装置１６が高圧側流量調整装置となる。そして、配管１２が低圧側配管となり、第二連結管１５が低圧側連結管に、第二流量調整装置１７が低圧側流量調整装置となる。 On the other hand, when the cooling operation mode is executed, the pipe 11 becomes a high-pressure side pipe, the first connection pipe 14 becomes a high-pressure side connection pipe, and the first flow rate adjustment device 16 becomes a high-pressure side flow rate adjustment apparatus. Then, the pipe 12 becomes a low pressure side pipe, the second connecting pipe 15 becomes a low pressure side connecting pipe, and the second flow rate adjusting device 17 becomes a low pressure side flow rate adjusting apparatus.

このとき、高圧側流量調整装置である第一流量調整装置１６の開度を低圧側流量調整装置である第二流量調整装置１７の開度よりも小さくする、あるいは第二流量調整装置１７を開き、第一流量調整装置１６を閉じる。制御装置２０は、この第一流量調整装置１６及び第二流量調整装置１７の開度の関係を維持しつつ、実験により求めた所定の開度とすることで、必要量の冷媒を冷媒回路に戻すことができ、その分、循環冷媒量が増加して冷房定格運転における最適冷媒量とすることができる。 At this time, the opening degree of the first flow rate adjustment device 16 that is the high pressure side flow rate adjustment device is made smaller than the opening degree of the second flow rate adjustment device 17 that is the low pressure side flow rate adjustment device, or the second flow rate adjustment device 17 is opened. The first flow rate adjusting device 16 is closed. The control device 20 maintains the relationship between the opening amounts of the first flow rate adjusting device 16 and the second flow rate adjusting device 17 and sets the required opening amount obtained by experiment to a necessary amount of refrigerant in the refrigerant circuit. The amount of circulating refrigerant can be increased by that amount, and the optimum amount of refrigerant in the cooling rated operation can be obtained.

このように、空調運転を開始したときから、冷媒回路を循環する冷媒が最適冷媒量となるように第一流量調整装置１６及び第二流量調整装置１７を制御することにより、空調能力を高めることができる。したがって、運転効率が向上して、省エネ運転を実現できる。 As described above, the air conditioning capacity is increased by controlling the first flow rate adjusting device 16 and the second flow rate adjusting device 17 so that the refrigerant circulating in the refrigerant circuit has the optimum refrigerant amount from the start of the air conditioning operation. Can do. Therefore, driving efficiency is improved and energy-saving driving can be realized.

空調運転の種類の他の判別方法として、室温に基づいて開始される空調運転の種類を決める。制御装置２０は、リモコンなどからの運転指示が入力されると、室温センサ２４から室温情報を取得する。制御装置２０は、現在の室温に基づいて空調運転の種類を判別する。室温に基づいて空調運転の種類を判別するタイミングは、運転指示が入力された後の運転開始する前あるいは運転開始直後とされる。 As another method for determining the type of air-conditioning operation, the type of air-conditioning operation started based on room temperature is determined. The control device 20 acquires room temperature information from the room temperature sensor 24 when an operation instruction from a remote controller or the like is input. The control device 20 determines the type of air conditioning operation based on the current room temperature. The timing for discriminating the type of the air-conditioning operation based on the room temperature is set before the start of the operation after the operation instruction is input or immediately after the start of the operation.

現在の室温Ｔと第１規定温度Ｔｗおよび第２規定温度Ｔｃ（Ｔｗ＜Ｔｃ）とが比較される。現在の室温Ｔが第１規定温度Ｔｗ以下（Ｔ≦Ｔｗ）の場合、制御装置２０は、暖房運転であると判別する。現在の室温Ｔが第２規定温度Ｔｃ以上（Ｔ≧Ｔｃ）の場合、制御装置２０は、冷房運転であると判別する。 The current room temperature T is compared with the first specified temperature Tw and the second specified temperature Tc (Tw <Tc). When the current room temperature T is equal to or lower than the first specified temperature Tw (T ≦ Tw), the control device 20 determines that the heating operation is being performed. When the current room temperature T is equal to or higher than the second specified temperature Tc (T ≧ Tc), the control device 20 determines that the cooling operation is being performed.

Ｔｗ＜Ｔ＜Ｔｃの場合、制御装置２０は、送風運転であると判別する。送風運転の場合、制御装置２０は、室内機２の送風機２６を動作させる。冷凍サイクルの制御は行われないので、冷媒量調整制御は行われない。なお、第一流量調整装置１６及び第二流量調整装置１７は、開いた状態とされる。このように、室温によって空調運転の種類を判別する方法は、室温に応じて冷房運転あるいは暖房運転を自動的に選択する自動運転が行われる場合に有用である。 In the case of Tw <T <Tc, the control device 20 determines that it is a blowing operation. In the case of the air blowing operation, the control device 20 operates the air blower 26 of the indoor unit 2. Since the control of the refrigeration cycle is not performed, the refrigerant amount adjustment control is not performed. Note that the first flow rate adjusting device 16 and the second flow rate adjusting device 17 are opened. Thus, the method of discriminating the type of the air-conditioning operation based on the room temperature is useful when the automatic operation for automatically selecting the cooling operation or the heating operation according to the room temperature is performed.

冷房あるいは暖房の空調運転を行うとき、圧縮機３の運転が開始されると、圧縮機３から吐出する冷媒の温度は徐々に上昇する。吐出温度がほぼ一定になると、冷媒回路の運転、すなわち、空調運転が安定する。空調運転の安定後、制御装置２０は、冷媒量調整制御を続行する。 When performing the air conditioning operation for cooling or heating, when the operation of the compressor 3 is started, the temperature of the refrigerant discharged from the compressor 3 gradually increases. When the discharge temperature becomes substantially constant, the operation of the refrigerant circuit, that is, the air conditioning operation is stabilized. After the air conditioning operation is stabilized, the control device 20 continues the refrigerant amount adjustment control.

循環する冷媒量が最適冷媒量で、環境条件、圧縮機の回転数及び絞り装置の開度が一定となり、空調運転が安定した状態では、冷媒の凝縮温度・蒸発温度、過冷却度（基準過冷却度）及び過熱度（基準過熱度）の値が決まる。なお、冷房運転時には、室外熱交換器４が凝縮器となり、室内熱交換器７が蒸発器となる。暖房運転時には室内熱交換器７が凝縮器となり、室外熱交換器４が蒸発器となる。 When the circulating refrigerant amount is the optimum refrigerant amount, the environmental conditions, the compressor speed and the opening of the throttle device are constant, and the air conditioning operation is stable, the refrigerant condensing temperature / evaporating temperature, the degree of supercooling (standard overcooling) The value of the degree of cooling) and the degree of superheat (reference superheat degree) are determined. In the cooling operation, the outdoor heat exchanger 4 serves as a condenser, and the indoor heat exchanger 7 serves as an evaporator. During the heating operation, the indoor heat exchanger 7 serves as a condenser, and the outdoor heat exchanger 4 serves as an evaporator.

制御装置２０は、空調運転が安定した後、凝縮器の出口温度及び蒸発器の出口温度を測定することにより、過冷却度の実測値及び過熱度の実測値を算出する。そして、これらの実測値と、基準過冷却度及び基準過熱度との間に差があるときは、その温度差がなくなるように第一流量調整装置１６及び第二流量調整装置１７の開度を調整する。 After the air-conditioning operation is stabilized, the control device 20 calculates the actual value of the degree of supercooling and the actual value of the degree of superheat by measuring the outlet temperature of the condenser and the outlet temperature of the evaporator. And when there is a difference between these measured values and the reference supercooling degree and the reference superheat degree, the opening degree of the first flow rate adjusting device 16 and the second flow rate adjusting device 17 is set so that the temperature difference is eliminated. adjust.

具体的に、凝縮器の出口温度と基準過冷却度との差、及び、蒸発器の出口温度と基準過熱度との差と、これらの温度差を解消するために必要な第一流量調整装置１６及び第二流量調整装置１７の開度の調整値をあらかじめ実験で求め、そのデータを制御装置２０に記憶しておく。これにより、制御装置２０は、凝縮器出口の実際の温度及び蒸発器出口の実際の温度に応じて、制御装置２０が実験で得たデータを基にして第一流量調整装置１６及び第二流量調整装置１７の開度の調整を行うことにより、最適冷媒量に正確に調整することができる。 Specifically, the difference between the outlet temperature of the condenser and the reference supercooling degree, the difference between the outlet temperature of the evaporator and the reference superheat degree, and the first flow rate adjustment device necessary to eliminate these temperature differences 16 and the adjustment value of the opening degree of the second flow rate adjusting device 17 are obtained in advance by experiments, and the data is stored in the control device 20. As a result, the control device 20 determines the first flow rate adjusting device 16 and the second flow rate based on the data obtained by the control device 20 in the experiment according to the actual temperature at the condenser outlet and the actual temperature at the evaporator outlet. By adjusting the opening degree of the adjusting device 17, it is possible to accurately adjust the optimum refrigerant amount.

空調運転中、室温と設定温度とに温度差があると、制御装置２０は、温度差が小さくなるように圧縮機３の回転数および絞り装置５の開度を変化させる。このとき、制御装置２０は、圧縮機３の回転数、外気温などに応じて、第一流量調整装置１６及び第二流量調整装置１７の開度を調整する。例えば、圧縮機３の回転数が上がると、制御装置２０は、最適冷媒量が多くなるように、高圧側流量調整装置６の開度を小さくする、あるいは低圧側流量調整装置７の開度を大きくする。 If there is a temperature difference between the room temperature and the set temperature during the air conditioning operation, the control device 20 changes the rotation speed of the compressor 3 and the opening degree of the expansion device 5 so that the temperature difference becomes small. At this time, the control device 20 adjusts the opening degree of the first flow rate adjustment device 16 and the second flow rate adjustment device 17 according to the rotation speed of the compressor 3, the outside air temperature, and the like. For example, when the rotation speed of the compressor 3 increases, the control device 20 decreases the opening of the high-pressure flow rate adjustment device 6 or increases the opening of the low-pressure flow adjustment device 7 so that the optimum refrigerant amount increases. Enlarge.

図３に示すように、空調運転の開始後、ある程度時間が経過すると、室温が設定温度に達する。制御装置２０は、圧縮機３を停止させ、送風機２６だけを動作させる。そして、室温と設定温度とに温度差が生じると、制御装置２０は、再び、圧縮機３の運転を開始する。このように、空調運転中、圧縮機３の運転のオンオフを繰り返すサーモオフが行われる。 As shown in FIG. 3, the room temperature reaches the set temperature after a certain amount of time has elapsed after the start of the air conditioning operation. The control device 20 stops the compressor 3 and operates only the blower 26. And if a temperature difference arises between room temperature and preset temperature, the control apparatus 20 will start the driving | operation of the compressor 3 again. In this way, during the air conditioning operation, the thermo-off that repeats the on / off operation of the compressor 3 is performed.

サーモオフ時にも冷媒量調整制御が行われる。制御装置２０は、サーモオフ時に圧縮機３が運転を開始するとき、第一流量調整装置１６及び第二流量調整装置１７の開度を調整する。第一流量調整装置１６及び第二流量調整装置１７の開度は、圧縮機３の回転数に応じて調整される。 The refrigerant amount adjustment control is also performed when the thermostat is off. The control device 20 adjusts the opening degree of the first flow rate adjustment device 16 and the second flow rate adjustment device 17 when the compressor 3 starts operation when the thermostat is off. The opening degree of the first flow rate adjusting device 16 and the second flow rate adjusting device 17 is adjusted according to the rotational speed of the compressor 3.

すなわち、制御装置２０は、サーモオフにより圧縮機３が停止するとき、停止前の圧縮機３の回転数および第一流量調整装置１６及び第二流量調整装置１７の開度をメモリに記憶する。そして、制御装置２０は、圧縮機３の運転を開始するとき、現在の室温に基づいて圧縮機３の回転数を決め、この回転数に応じて第一流量調整装置１６及び第二流量調整装置１７の開度を設定する。 That is, when the compressor 3 is stopped due to thermo-off, the control device 20 stores the rotational speed of the compressor 3 and the opening degrees of the first flow rate adjusting device 16 and the second flow rate adjusting device 17 before the stop in the memory. Then, when starting the operation of the compressor 3, the control device 20 determines the number of rotations of the compressor 3 based on the current room temperature, and the first flow rate adjustment device 16 and the second flow rate adjustment device according to this rotation number. An opening of 17 is set.

図４に示すように、圧縮機３の回転数がＡ、第一流量調整装置１６及び第二流量調整装置１７の開度がａ１，ａ２で空調運転が行われている。室温が設定温度になると、制御装置２０は、圧縮機３を停止し、送風運転を行う。室温が変化して、室温と設定温度とに温度差が生じると、制御装置２０は、圧縮機３の運転を開始する。制御装置２０は、室温と設定温度との温度差に応じて圧縮機３の回転数Ｂを決め、この回転数に応じて第一流量調整装置１６及び第二流量調整装置１７の開度を決める。なお、制御装置２０は、圧縮機３を停止した際に、送風運転も停止してもよい。この場合、室温が変化して、室温と設定温度とに温度差が生じると、制御装置２０は、空調運転（圧縮機３の運転及び送風運転）を再開する。 As shown in FIG. 4, the air conditioning operation is performed with the rotation speed of the compressor 3 being A, and the opening amounts of the first flow rate adjusting device 16 and the second flow rate adjusting device 17 being a1 and a2. When the room temperature reaches the set temperature, the control device 20 stops the compressor 3 and performs the air blowing operation. When the room temperature changes and a temperature difference occurs between the room temperature and the set temperature, the control device 20 starts the operation of the compressor 3. The control device 20 determines the rotation speed B of the compressor 3 according to the temperature difference between the room temperature and the set temperature, and determines the opening degrees of the first flow rate adjustment device 16 and the second flow rate adjustment device 17 according to this rotation speed. . The control device 20 may also stop the air blowing operation when the compressor 3 is stopped. In this case, when the room temperature changes and a temperature difference occurs between the room temperature and the set temperature, the control device 20 resumes the air conditioning operation (the operation of the compressor 3 and the air blowing operation).

圧縮機３の停止前の回転数Ａと運転開始時の回転数Ｂとが同じとき、第一流量調整装置１６及び第二流量調整装置１７の開度は、運転停止前の開度と同じにされる。各第一流量調整装置１６及び第二流量調整装置１７の開度はそれぞれａ１，ａ２に固定される。この場合、絞り装置５および第一流量調整装置１６及び第二流量調整装置１７は全開されることなく、そのままの開度で圧縮機３の運転が再開される。 When the rotation speed A before the stop of the compressor 3 and the rotation speed B at the start of operation are the same, the opening degree of the first flow rate adjustment device 16 and the second flow rate adjustment device 17 is the same as the opening degree before the operation stop. Is done. The opening degree of each first flow rate adjusting device 16 and second flow rate adjusting device 17 is fixed to a1 and a2, respectively. In this case, the operation of the compressor 3 is restarted with the opening as it is, without fully opening the throttle device 5, the first flow rate adjusting device 16, and the second flow rate adjusting device 17.

このように、絞り装置５などの開度の調整を行う必要がないので、圧縮機３の運転をすぐに開始でき、室温を設定温度にするまでの時間を短縮できる。また、運転条件は変わらないので、すぐに最適冷媒量をとなり、効率のよい運転を行え、省エネを図れる。 Thus, since it is not necessary to adjust the opening degree of the expansion device 5 or the like, the operation of the compressor 3 can be started immediately, and the time until the room temperature is set to the set temperature can be shortened. In addition, since the operating conditions do not change, the optimum refrigerant amount can be obtained immediately, efficient operation can be performed, and energy can be saved.

圧縮機３の停止前の回転数Ａと運転開始時の回転数Ｂとが異なるとき、第一流量調整装置１６及び第二流量調整装置１７の開度は、運転停止前の開度から変更され、開度はそれぞれｂ１，ｂ２となる。制御装置２０は、第一流量調整装置１６及び第二流量調整装置１７を一旦全開して、冷媒回路の圧力の平衡をとってから、決められた開度にし、圧縮機３を動作させる。以降、室温が設定温度に達するまで、空調運転が行われる。例えば、圧縮機３の回転数が上がると、制御装置２０は、最適冷媒量が多くなるように、高圧側流量調整装置の開度を小さくし、低圧側流量調整装置の開度を大きくする。 When the rotation speed A before the stop of the compressor 3 and the rotation speed B at the start of operation are different, the opening degree of the first flow rate adjustment device 16 and the second flow rate adjustment device 17 is changed from the opening degree before the operation stop. The opening amounts are b1 and b2, respectively. The control device 20 opens the first flow rate adjustment device 16 and the second flow rate adjustment device 17 once to balance the pressure in the refrigerant circuit, and then operates the compressor 3 with the determined opening degree. Thereafter, the air conditioning operation is performed until the room temperature reaches the set temperature. For example, when the rotation speed of the compressor 3 increases, the control device 20 decreases the opening of the high-pressure side flow control device and increases the opening of the low-pressure flow control device so that the optimum refrigerant amount increases.

このように、圧縮機３の運転開始時に圧縮機３の回転数に応じて第一流量調整装置１６及び第二流量調整装置１７の開度を調整することにより、すばやく室温を設定温度にすることができ、利用者の快適性を向上できる。また、圧縮機３が停止する時間が長くなり、省エネ運転を実現できる。 Thus, the room temperature can be quickly set to the set temperature by adjusting the opening of the first flow rate adjusting device 16 and the second flow rate adjusting device 17 according to the rotation speed of the compressor 3 at the start of operation of the compressor 3. Can improve user comfort. Moreover, the time for which the compressor 3 is stopped becomes longer, and an energy saving operation can be realized.

ところで、空調運転中、運転状況に変化があったとき、制御装置２０は、運転状況の変化に応じて第一流量調整装置１６及び第二流量調整装置１７を制御する。特に、外気温センサ２５により検出された外気温に応じて、第一流量調整装置１６及び第二流量調整装置１７の開度が調整される。 By the way, when there is a change in the operating status during the air conditioning operation, the control device 20 controls the first flow rate adjusting device 16 and the second flow rate adjusting device 17 in accordance with the change in the operating status. In particular, the opening amounts of the first flow rate adjusting device 16 and the second flow rate adjusting device 17 are adjusted according to the outside air temperature detected by the outside air temperature sensor 25.

圧縮機３の運転開始時の外気温が圧縮機３の停止時の外気温から変化したとき、制御装置２０は、外気温および室温に基づいて圧縮機３の回転数を決める。例えば、冷房運転のとき、外気温が上がると、圧縮機３の回転数が停止前の回転数よりも上げられる。この回転数に応じて、冷媒回路を循環する冷媒の最適冷媒量が多くなるように、高圧側流量調整装置である第一流量調整装置１６の開度を小さくし、低圧側流量調整装置である第二流量調整装置１７の開度を大きくする。 When the outside air temperature at the start of operation of the compressor 3 changes from the outside air temperature when the compressor 3 is stopped, the control device 20 determines the rotation speed of the compressor 3 based on the outside air temperature and the room temperature. For example, during the cooling operation, when the outside air temperature rises, the rotational speed of the compressor 3 is increased more than the rotational speed before stopping. According to this rotational speed, the opening degree of the first flow rate adjustment device 16 that is the high-pressure side flow rate adjustment device is reduced so that the optimum refrigerant amount of the refrigerant circulating in the refrigerant circuit is increased, and thus the low-pressure side flow rate adjustment device. The opening degree of the second flow rate adjusting device 17 is increased.

外気温が下がった場合も、同様に最適冷媒量が少なくなるように、第一流量調整装置１６及び第二流量調整装置１７の開度が調整される。また、暖房運転の場合でも、同様に、外気温の変化に応じて最適冷媒量が増減するように、第一流量調整装置１６及び第二流量調整装置１７の開度が調整される。 Similarly, when the outside air temperature decreases, the opening amounts of the first flow rate adjustment device 16 and the second flow rate adjustment device 17 are adjusted so that the optimum refrigerant amount decreases. Similarly, in the heating operation, the opening amounts of the first flow rate adjustment device 16 and the second flow rate adjustment device 17 are adjusted so that the optimum refrigerant amount increases or decreases according to the change in the outside air temperature.

このように、外気温の変化に応じて第一流量調整装置１６及び第二流量調整装置１７の開度を調整することにより、運転状況が変化しても、最適な冷媒量で冷媒が冷媒回路を循環する。したがって、効率のよい運転を行え、省エネとなる。 In this way, by adjusting the opening degree of the first flow rate adjusting device 16 and the second flow rate adjusting device 17 in accordance with the change in the outside air temperature, the refrigerant is circulated in the refrigerant circuit with an optimal amount of refrigerant even if the operating state changes. Circulate. Therefore, efficient operation can be performed and energy saving can be achieved.

本実施形態では第一流量調整装置１６が全閉しないように制御される。そこで、第一流量調整装置１６として全閉しない構造の流量調整装置を用いれば、第一流量調整装置１６が全閉する事態を確実に阻止することが可能となる。全閉しない構造の流量調整装置として、具体的には、弁体が全閉位置の手前で物理的にストップして弁体と弁座との間に隙間を確保する構造のものや、弁体自身に切込み等を設けることで全閉位置において冷媒の流通を確保する構造のものを用いることができる。なお、第二流量調整装置１７も全閉しないように制御すること、さらに、第二流量調整装置１７も全閉しない構造の流量調整装置としてもよいことはもちろんである。 In the present embodiment, the first flow rate adjusting device 16 is controlled so as not to be fully closed. Accordingly, if a flow rate adjusting device having a structure that is not fully closed is used as the first flow rate adjusting device 16, it is possible to reliably prevent the first flow rate adjusting device 16 from being fully closed. As a flow control device with a structure that does not fully close, specifically, a valve body that is physically stopped before the fully closed position to secure a gap between the valve body and the valve seat, or a valve body By providing a notch or the like in itself, a structure that ensures the circulation of the refrigerant in the fully closed position can be used. It goes without saying that the second flow rate adjusting device 17 is controlled not to be fully closed, and the second flow rate adjusting device 17 may be a flow rate adjusting device having a structure that is not fully closed.

本発明は、上記実施形態に限定されるものではなく、本発明の範囲内で上記実施形態に多くの修正および変更を加えることができる。具体的に、上記実施形態では第一連結管１４及び第二連結管１５の一端側はそれぞれ冷媒回路の配管１１及び１２に接続され、他端側はそれぞれ個々にレシーバ１３に接続されているが、これに限らず、たとえば、図５に示すように、第一連結管１４及び第二連結管１５の他端側を集合させた後に、一本の連結管としてレシーバ１３に接続することも可能である。 The present invention is not limited to the above embodiment, and many modifications and changes can be made to the above embodiment within the scope of the present invention. Specifically, in the above embodiment, one end side of the first connecting pipe 14 and the second connecting pipe 15 is connected to the pipes 11 and 12 of the refrigerant circuit, respectively, and the other end side is individually connected to the receiver 13. Not limited to this, for example, as shown in FIG. 5, after the other end sides of the first connecting pipe 14 and the second connecting pipe 15 are assembled, it is possible to connect to the receiver 13 as a single connecting pipe. It is.

また、空調運転が安定したか否かを判断するのに、圧縮機３と吐出温度を検出し、検出温度変化が所定時間内で一定範囲内になったときに安定したと判断しているがこれに限らず、たとえば、所定時間内で凝縮器又は蒸発器の出口温度の温度変化が一定範囲内になったときに安定したと判断するようにしてもよい。 Further, to determine whether the air-conditioning operation is stable, the compressor 3 and the discharge temperature are detected, and it is determined that the change is stable when the detected temperature change is within a certain range within a predetermined time. Not limited to this, for example, it may be determined that the temperature is stable when the temperature change of the outlet temperature of the condenser or the evaporator is within a certain range within a predetermined time.

１室外機
２室内機
３圧縮機
４室外熱交換器
５絞り装置
６二方弁
７室内熱交換器
８三方弁
９四方弁
１０冷媒量調整部
１１配管
１２配管
１３レシーバ
１４第一連結管
１５第二連結管
１６第一流量調整装置
１７第二流量調整装置
２０制御装置
２１温度センサ
２２温度センサ
２３吐出温度センサ
２４室温センサ
２５外気温センサ
２６送風機 DESCRIPTION OF SYMBOLS 1 Outdoor unit 2 Indoor unit 3 Compressor 4 Outdoor heat exchanger 5 Throttle device 6 Two-way valve 7 Indoor heat exchanger 8 Three-way valve 9 Four-way valve 10 Refrigerant amount adjustment part 11 Pipe 12 Pipe 13 Receiver 14 First connection pipe 15 1st Two connection pipes 16 First flow rate adjusting device 17 Second flow rate adjusting device 20 Control device 21 Temperature sensor 22 Temperature sensor 23 Discharge temperature sensor 24 Room temperature sensor 25 Outside air temperature sensor 26 Blower

Claims

A compressor, a condenser, a throttling device, and an evaporator are sequentially connected by a pipe to form a refrigerant circuit through which refrigerant flows, and a refrigerant amount adjusting unit that adjusts the amount of refrigerant flowing through the refrigerant circuit is provided in parallel with the throttling device. The refrigerant amount adjusting unit is configured to connect a receiver that collects refrigerant by using a pressure of refrigerant flowing from a high-pressure side pipe before and after the expansion device to a low-pressure side pipe, and a high-pressure side connection that connects the receiver and the high-pressure side pipe. A low-pressure side connecting pipe that connects the pipe and the receiver and the low-pressure side pipe, and a high-pressure side flow adjusting device and a low-pressure side that are interposed in the high-pressure side connecting pipe and the low-pressure side connecting pipe, respectively. An air conditioner including a flow rate adjusting device, wherein a controller for controlling the opening degree of the high pressure side flow rate adjusting device and the low pressure side flow rate adjusting device is provided, and the control device includes a high pressure side flow rate adjusting device and a low flow rate adjusting device. An air conditioner characterized by the opening adjustment so as not to fully close at least one of the side flow rate adjusting device.

The controller is configured to input the set temperature, the room temperature detected by the room temperature sensor, and the outside air temperature detected by the outside air temperature sensor, based on the operation condition data stored in advance, the rotation speed of the compressor, The air conditioner according to claim 1, wherein the opening degree of the throttle device, the opening degree of the high pressure side flow rate adjustment device, and the opening degree of the low pressure side flow rate adjustment device are controlled.

When it is determined that the operation state is stable, the control device opens the high-pressure side flow control device and opens the low-pressure side flow control device according to the outlet temperature of the condenser and the outlet temperature of the evaporator. The air conditioner according to claim 2, wherein the degree is adjusted.

The air conditioner according to any one of claims 1 to 3, wherein at least one of the high-pressure side flow rate adjustment device and the low-pressure side flow rate adjustment device is a flow rate adjustment device that is not fully closed.