JP4858399B2

JP4858399B2 - Refrigeration cycle

Info

Publication number: JP4858399B2
Application number: JP2007269438A
Authority: JP
Inventors: 昌宏高津; 進川村; 丈二黒木; 輝彦平
Original assignee: Denso Corp
Current assignee: Denso Corp
Priority date: 2007-10-16
Filing date: 2007-10-16
Publication date: 2012-01-18
Anticipated expiration: 2027-10-16
Also published as: DE102008051510B4; JP2009097786A; DE102008051510A1

Description

本発明は、複数の冷媒減圧手段を並列に備え複数の冷媒蒸発器へ供給される冷媒の減圧状態を調節する蒸気圧縮式の冷凍サイクルに関する。 The present invention relates to a vapor compression refrigeration cycle that includes a plurality of refrigerant decompression means in parallel and adjusts the decompression state of refrigerant supplied to a plurality of refrigerant evaporators.

従来技術として、下記特許文献１に開示された蒸気圧縮式の冷凍サイクルがある。この特許文献１では、冷媒環状通路内において冷媒減圧手段および冷媒循環手段の役割を果たすエジェクタの冷媒流れ下流側に第１蒸発器を配置するともに、環状通路のエジェクタ上流部から分岐しエジェクタの冷媒吸入口に至る冷媒分岐通路に減圧手段と第２蒸発器を設け、冷媒蒸発温度の異なる第１蒸発器と第２蒸発器とを空気流れ方向に並設した冷凍サイクルが開示されている。 As a prior art, there is a vapor compression refrigeration cycle disclosed in Patent Document 1 below. In this Patent Document 1, a first evaporator is disposed on the downstream side of the refrigerant flow of an ejector serving as a refrigerant decompression unit and a refrigerant circulation unit in the refrigerant annular passage, and the refrigerant of the ejector is branched from the upstream portion of the ejector in the annular passage. There is disclosed a refrigeration cycle in which a decompression means and a second evaporator are provided in a refrigerant branch passage leading to an intake port, and a first evaporator and a second evaporator having different refrigerant evaporation temperatures are arranged in parallel in the air flow direction.

この冷凍サイクルでは、エジェクタの減圧手段としてのノズル部もしくはノズル部上流側に別に設けた減圧手段、または分岐通路に設けた減圧手段のいずれか１つを減圧量可変式とし、ノズル部から噴射する冷媒流量と冷媒吸入口から吸入される冷媒流量との比を調節して、両蒸発器における吸熱能力が効率よく発揮できるようになっている。
特開２００７−７８３３９号公報 In this refrigeration cycle, any one of the pressure reducing means provided on the upstream side of the nozzle part or the nozzle part as the pressure reducing means of the ejector, or the pressure reducing means provided in the branch passage is variable pressure reduction type, and is injected from the nozzle part. By adjusting the ratio between the refrigerant flow rate and the refrigerant flow rate sucked from the refrigerant suction port, the heat absorption capability of both evaporators can be efficiently exhibited.
JP 2007-78339 A

上記従来技術のように複数の減圧手段を並列に備え複数の蒸発器へ供給される冷媒の状態を調節する冷凍サイクルに対し、本発明者らは、一層の性能向上を目指して鋭意検討を行なった結果、環状通路に設ける減圧手段および分岐通路に設ける減圧手段のいずれも減圧量可変式とし、サイクル内を流通する冷媒の状態を適切に調節すれば、更なる効率の向上が可能であることを見出した。 For the refrigeration cycle that adjusts the state of refrigerant supplied to a plurality of evaporators in parallel with a plurality of decompression means as in the prior art described above, the present inventors have conducted intensive studies with the aim of further improving performance. As a result, if both the decompression means provided in the annular passage and the decompression means provided in the branch passage are variable in pressure reduction type and the state of the refrigerant flowing in the cycle is appropriately adjusted, further improvement in efficiency can be achieved. I found.

本発明は、上記点に鑑みてなされたものであり、複数の可変式減圧手段による冷媒減圧量を制御して、効率を更に向上することが可能な冷凍サイクルを提供することを目的とする。 The present invention has been made in view of the above points, and an object of the present invention is to provide a refrigeration cycle capable of further improving efficiency by controlling the refrigerant pressure reduction amount by a plurality of variable pressure reducing means.

上記目的を達成するため、請求項１に記載の発明では、
冷媒を吸入圧縮して吐出する圧縮機（１１）と、
圧縮機（１１）から吐出された冷媒の放熱を行なう放熱器（１２）と、
放熱器（１２）から流出した冷媒を減圧膨張させる減圧量可変式の第１減圧手段（１３ａ）と、
第１減圧手段（１３ａ）で減圧した冷媒を蒸発させる第１蒸発器（１４）と、
第１蒸発器（１４）で蒸発した冷媒を圧縮機（１１）に吸入させるように、圧縮機（１１）、放熱器（１２）、第１減圧手段（１３ａ）、第１蒸発器（１４）を環状に接続した環状通路（１０）と、
環状通路（１０）の放熱器（１２）と第１減圧手段（１３ａ）との間から分岐するように設けられ、放熱器（１２）から流出した冷媒の一部を、第１減圧手段（１３ａ）を迂回させて第１減圧手段（１３ａ）から圧縮機（１１）に向かう冷媒と合流するように導く分岐通路（２０）と、
分岐通路（２０）に設けられ、放熱器（１２）から流出した冷媒を減圧膨張させる減圧量可変式の第２減圧手段（２３）と、
分岐通路（２０）に設けられ、第２減圧手段（２３）で減圧した冷媒を蒸発させる第２蒸発器（２４）と、
第１減圧手段（１３ａ）および第２減圧手段（２３）の減圧量を制御する制御手段（１００）と、を備え、
第１蒸発器（１４）と第２蒸発器（２４）とが、第１蒸発器（１４）を通過した後の外部流体が第２蒸発器（２４）を通過するように配置された冷凍サイクルであって、
制御手段（１００）は、
第１減圧手段（１３ａ）および第２減圧手段（２３）のうち一方の減圧量を、圧縮機（１１）から吐出され第１、第２減圧手段（１３ａ、２３）で減圧される前の冷媒の圧力もしくは温度に基づいて制御し、
第１減圧手段（１３ａ）および第２減圧手段（２３）のうち他方の減圧量を、第１蒸発器（１４）内の冷媒と第２蒸発器（２４）内の冷媒との圧力差、もしくは圧力差に関連する物理量に基づいて制御するものであり、
制御手段（１００）は、
第１減圧手段（１３ａ）および第２減圧手段（２３）のうち他方の減圧量を、第１蒸発器（１４）内の冷媒と第２蒸発器（２４）内の冷媒との圧力差もしくは圧力差に関連する物理量が目標値と一致するように制御しており、
放熱器（１２）へ流入する外部流体の温度、放熱器（１２）から流出する外部流体の温度、第１蒸発器（１４）へ流入する外部流体の温度、および、第１蒸発器（１４）へ流入する外部流体の湿度の少なくともいずれかに応じて、目標値を変更することを特徴としている。 In order to achieve the above object, in the invention described in claim 1,
A compressor (11) for sucking and compressing and discharging the refrigerant;
A radiator (12) that radiates heat of the refrigerant discharged from the compressor (11);
A first depressurizing means (13a) of variable depressurization amount for depressurizing and expanding the refrigerant flowing out of the radiator (12);
A first evaporator (14) for evaporating the refrigerant decompressed by the first decompression means (13a);
The compressor (11), the radiator (12), the first pressure reducing means (13a), and the first evaporator (14) so that the refrigerant evaporated in the first evaporator (14) is sucked into the compressor (11). An annular passage (10) connected in an annular shape;
A part of the refrigerant that is provided so as to branch from between the radiator (12) of the annular passage (10) and the first decompression means (13a) is discharged to the first decompression means (13a). ) And a branch passage (20) for guiding the refrigerant to join the refrigerant from the first pressure reducing means (13a) toward the compressor (11),
A second depressurizing means (23) having a variable amount of depressurization provided in the branch passage (20) and depressurizing and expanding the refrigerant flowing out of the radiator (12);
A second evaporator (24) provided in the branch passage (20) and evaporating the refrigerant decompressed by the second decompression means (23);
Control means (100) for controlling the amount of decompression of the first decompression means (13a) and the second decompression means (23),
A refrigeration cycle in which the first evaporator (14) and the second evaporator (24) are arranged so that the external fluid after passing through the first evaporator (14) passes through the second evaporator (24). Because
The control means (100)
One of the first decompression means (13a) and the second decompression means (23) is decompressed by the refrigerant before being decompressed by the first and second decompression means (13a, 23) from the compressor (11). Control based on the pressure or temperature of
The pressure reduction amount of the other of the first decompression means (13a) and the second decompression means (23) is set to the pressure difference between the refrigerant in the first evaporator (14) and the refrigerant in the second evaporator (24), or Control based on physical quantity related to pressure difference ,
The control means (100)
The pressure reduction amount or pressure between the refrigerant in the first evaporator (14) and the refrigerant in the second evaporator (24) is determined as the other pressure reduction amount of the first pressure reducing means (13a) and the second pressure reducing means (23). The physical quantity related to the difference is controlled to match the target value,
The temperature of the external fluid flowing into the radiator (12), the temperature of the external fluid flowing out of the radiator (12), the temperature of the external fluid flowing into the first evaporator (14), and the first evaporator (14) The target value is changed in accordance with at least one of the humidity of the external fluid flowing into the .

これによると、圧縮機（１１）から吐出され第１、第２減圧手段（１３ａ、２３）で減圧される前の冷媒の状態、すなわち高圧側の冷媒状態を、放熱器（１２）における放熱の効率が好適となる冷媒状態とすることが可能であり、かつ、第１蒸発器（１４）内の冷媒と第２蒸発器（２４）内の冷媒との温度差を、外部流体の流れ方向（ＡＡ）に並設された第１蒸発器（１４）、第２蒸発器（２４）において着霜を抑制して外部流体から吸熱する効率が好適となる温度差とすることが可能である。このようにして、冷凍サイクル（１）の効率を更に向上することが可能である。
また、放熱器（１２）、第１蒸発器（１４）、第２蒸発器（２４）の外部流体の温度や、第１蒸発器（１４）、第２蒸発器（２４）の着霜状態等の環境条件が変化した場合であっても、好適な第１蒸発器（１４）内の冷媒と第２蒸発器（２４）内の冷媒との圧力差を確保しつつ運転することが可能である。
また、請求項２に記載の発明では、
冷媒を吸入圧縮して吐出する圧縮機（１１）と、
圧縮機（１１）から吐出された冷媒の放熱を行なう放熱器（１２）と、
放熱器（１２）から流出した冷媒を減圧膨張させる減圧量可変式の第１減圧手段（１３ａ）と、
第１減圧手段（１３ａ）で減圧した冷媒を蒸発させる第１蒸発器（１４）と、
第１蒸発器（１４）で蒸発した冷媒を圧縮機（１１）に吸入させるように、圧縮機（１１）、放熱器（１２）、第１減圧手段（１３ａ）、第１蒸発器（１４）を環状に接続した環状通路（１０）と、
環状通路（１０）の放熱器（１２）と第１減圧手段（１３ａ）との間から分岐するように設けられ、放熱器（１２）から流出した冷媒の一部を、第１減圧手段（１３ａ）を迂回させて第１減圧手段（１３ａ）から圧縮機（１１）に向かう冷媒と合流するように導く分岐通路（２０）と、
分岐通路（２０）に設けられ、放熱器（１２）から流出した冷媒を減圧膨張させる減圧量可変式の第２減圧手段（２３）と、
分岐通路（２０）に設けられ、第２減圧手段（２３）で減圧した冷媒を蒸発させる第２蒸発器（２４）と、
第１減圧手段（１３ａ）および第２減圧手段（２３）の減圧量を制御する制御手段（１００）と、を備え、
第１蒸発器（１４）と第２蒸発器（２４）とが、第１蒸発器（１４）を通過した後の外部流体が第２蒸発器（２４）を通過するように配置された冷凍サイクルであって、
制御手段（１００）は、
第１減圧手段（１３ａ）および第２減圧手段（２３）のうち一方の減圧量を、圧縮機（１１）から吐出され第１、第２減圧手段（１３ａ、２３）で減圧される前の冷媒の圧力もしくは温度に基づいて制御し、
第１減圧手段（１３ａ）および第２減圧手段（２３）のうち他方の減圧量を、第１蒸発器（１４）内の冷媒と第２蒸発器（２４）内の冷媒との圧力差、もしくは圧力差に関連する物理量に基づいて制御するものであり、
制御手段（１００）は、
第１減圧手段（１３ａ）および第２減圧手段（２３）のうち他方の減圧量を、第１蒸発器（１４）内の冷媒と第２蒸発器（２４）内の冷媒との圧力差もしくは圧力差に関連する物理量が目標値と一致するように制御しており、
第１蒸発器（１４）、第２蒸発器（２４）の少なくともいずれかの外表面温度に応じて、目標値を変更することを特徴としている。
これによると、圧縮機（１１）から吐出され第１、第２減圧手段（１３ａ、２３）で減圧される前の冷媒の状態、すなわち高圧側の冷媒状態を、放熱器（１２）における放熱の効率が好適となる冷媒状態とすることが可能であり、かつ、第１蒸発器（１４）内の冷媒と第２蒸発器（２４）内の冷媒との温度差を、外部流体の流れ方向（ＡＡ）に並設された第１蒸発器（１４）、第２蒸発器（２４）において着霜を抑制して外部流体から吸熱する効率が好適となる温度差とすることが可能である。このようにして、冷凍サイクル（１）の効率を更に向上することが可能である。
また、第１蒸発器（１４）、第２蒸発器（２４）に着霜が始まり外表面の温度低下が発生した場合、すなわち着霜が進行し易い条件となった場合には、第１蒸発器（１４）と第２蒸発器（２４）との冷媒圧力差を拡大することで、第２蒸発器（２４）に対する第１蒸発器（１４）の温度が高くなるように両蒸発器（１４、２４）の温度差を大きくし、着霜を抑制することが可能である。 According to this, the state of the refrigerant before it is discharged from the compressor (11) and depressurized by the first and second decompression means (13a, 23), that is, the refrigerant state on the high-pressure side is changed to the heat radiation of the radiator (12). It is possible to obtain a refrigerant state in which efficiency is suitable, and the temperature difference between the refrigerant in the first evaporator (14) and the refrigerant in the second evaporator (24) is expressed as the flow direction of the external fluid ( In the first evaporator (14) and the second evaporator (24) arranged in parallel with AA), it is possible to suppress the frost formation and set the temperature difference so that the efficiency of absorbing heat from the external fluid is suitable. In this way, it is possible to further improve the efficiency of the refrigeration cycle (1).
Moreover, the temperature of the external fluid of the radiator (12), the first evaporator (14), the second evaporator (24), the frosting state of the first evaporator (14), the second evaporator (24), etc. Even when the environmental conditions change, it is possible to operate while securing a pressure difference between the refrigerant in the preferred first evaporator (14) and the refrigerant in the second evaporator (24). .
In the invention according to claim 2,
A compressor (11) for sucking and compressing and discharging the refrigerant;
A radiator (12) that radiates heat of the refrigerant discharged from the compressor (11);
A first depressurizing means (13a) of variable depressurization amount for depressurizing and expanding the refrigerant flowing out of the radiator (12);
A first evaporator (14) for evaporating the refrigerant decompressed by the first decompression means (13a);
The compressor (11), the radiator (12), the first pressure reducing means (13a), and the first evaporator (14) so that the refrigerant evaporated in the first evaporator (14) is sucked into the compressor (11). An annular passage (10) connected in an annular shape;
A part of the refrigerant that is provided so as to branch from between the radiator (12) of the annular passage (10) and the first decompression means (13a) is discharged to the first decompression means (13a). ) And a branch passage (20) for guiding the refrigerant to join the refrigerant from the first pressure reducing means (13a) toward the compressor (11),
A second depressurizing means (23) having a variable amount of depressurization provided in the branch passage (20) and depressurizing and expanding the refrigerant flowing out of the radiator (12);
A second evaporator (24) provided in the branch passage (20) and evaporating the refrigerant decompressed by the second decompression means (23);
Control means (100) for controlling the amount of decompression of the first decompression means (13a) and the second decompression means (23),
A refrigeration cycle in which the first evaporator (14) and the second evaporator (24) are arranged so that the external fluid after passing through the first evaporator (14) passes through the second evaporator (24). Because
The control means (100)
One of the first decompression means (13a) and the second decompression means (23) is decompressed by the refrigerant before being decompressed by the first and second decompression means (13a, 23) from the compressor (11). Control based on the pressure or temperature of
The pressure reduction amount of the other of the first decompression means (13a) and the second decompression means (23) is set to the pressure difference between the refrigerant in the first evaporator (14) and the refrigerant in the second evaporator (24), or Control based on physical quantity related to pressure difference,
The control means (100)
The pressure reduction amount or pressure between the refrigerant in the first evaporator (14) and the refrigerant in the second evaporator (24) is determined as the other pressure reduction amount of the first pressure reducing means (13a) and the second pressure reducing means (23). The physical quantity related to the difference is controlled to match the target value,
The target value is changed according to the outer surface temperature of at least one of the first evaporator (14) and the second evaporator (24).
According to this, the state of the refrigerant before it is discharged from the compressor (11) and depressurized by the first and second decompression means (13a, 23), that is, the refrigerant state on the high-pressure side is changed to the heat radiation of the radiator (12). It is possible to obtain a refrigerant state in which efficiency is suitable, and the temperature difference between the refrigerant in the first evaporator (14) and the refrigerant in the second evaporator (24) is expressed as the flow direction of the external fluid ( In the first evaporator (14) and the second evaporator (24) arranged in parallel with AA), it is possible to suppress the frost formation and set the temperature difference so that the efficiency of absorbing heat from the external fluid is suitable. In this way, it is possible to further improve the efficiency of the refrigeration cycle (1).
Further, when frosting starts in the first evaporator (14) and the second evaporator (24) and the temperature of the outer surface is reduced, that is, when the frosting is likely to proceed, the first evaporation is performed. By expanding the refrigerant pressure difference between the evaporator (14) and the second evaporator (24), the temperature of the first evaporator (14) with respect to the second evaporator (24) is increased so that both evaporators (14 , 24) can be increased to suppress frost formation.

また、請求項３に記載の発明では、
放熱器（１２）から流出した冷媒の圧力エネルギーを速度エネルギーに変換して冷媒を減圧膨張させるノズル部（１３ａ）、ノズル部（１３ａ）から噴射する冷媒流により冷媒が内部に吸引される冷媒吸引口（１３ｂ）、およびノズル部（１３ａ）から噴射する冷媒と冷媒吸引口（１３ｂ）から吸引した冷媒とを混合させながら速度エネルギーを圧力エネルギーに変換して冷媒の圧力を昇圧させる昇圧部（１３ｃ、１３ｄ）を有するエジェクタ（１３）を備え、
第１減圧手段（１３ａ）はエジェクタ（１３）のノズル部（１３ａ）であり、
分岐通路（２０）は、下流端がエジェクタ（１３）の冷媒吸入口（１３ｂ）に接続されて、第２蒸発器（２４）で蒸発した冷媒を冷媒吸入口（１３ｂ）に流入させることを特徴としている。 In the invention according to claim 3 ,
The nozzle part (13a) that converts the pressure energy of the refrigerant flowing out from the radiator (12) into velocity energy and decompresses and expands the refrigerant, and the refrigerant suction that the refrigerant is sucked in by the refrigerant flow injected from the nozzle part (13a) A booster (13c) that boosts the pressure of the refrigerant by converting the velocity energy into pressure energy while mixing the refrigerant injected from the nozzle (13b) and the nozzle (13a) and the refrigerant sucked from the refrigerant suction port (13b). , 13d) with an ejector (13),
The first pressure reducing means (13a) is the nozzle portion (13a) of the ejector (13),
The downstream end of the branch passage (20) is connected to the refrigerant suction port (13b) of the ejector (13), and the refrigerant evaporated in the second evaporator (24) flows into the refrigerant suction port (13b). It is said.

これによると、第１蒸発器（１４）内の冷媒と第２蒸発器（２４）内の冷媒との圧力差を、エジェクタ（１３）の昇圧効果によって熱移送の効率がより好適となるように調整することが可能である。したがって、冷凍サイクル（１）の効率を一層向上することが可能である。 According to this, the pressure difference between the refrigerant in the first evaporator (14) and the refrigerant in the second evaporator (24) is made more suitable for the efficiency of heat transfer due to the boosting effect of the ejector (13). It is possible to adjust. Therefore, it is possible to further improve the efficiency of the refrigeration cycle (1).

また、請求項４に記載の発明では、圧縮機（１１）から吐出され第１、第２減圧手段（１３ａ、２３）で減圧される前の冷媒の圧力を検出する圧力検出手段（９２）を備え、制御手段（１００）は、圧力検出手段（９２）が検出した圧力に基づいて、第１減圧手段（１３ａ）および第２減圧手段（２３）のうち一方の減圧量を制御することを特徴としている。 According to a fourth aspect of the present invention, the pressure detection means (92) for detecting the pressure of the refrigerant discharged from the compressor (11) and decompressed by the first and second decompression means (13a, 23) is provided. The control means (100) controls the pressure reduction amount of one of the first pressure reduction means (13a) and the second pressure reduction means (23) based on the pressure detected by the pressure detection means (92). It is said.

これによると、圧縮機（１１）から吐出され第１、第２減圧手段（１３ａ、２３）で減圧される前の冷媒の圧力、すなわち高圧側圧力を制御因子とすることで、圧縮機（１１）に吸入される冷媒の状態に関わらず放熱器（１２）による放熱の効率が好適となる冷媒状態まで圧力を高めることが可能である。 According to this, the pressure of the refrigerant before it is discharged from the compressor (11) and depressurized by the first and second decompression means (13a, 23), that is, the high-pressure side pressure is used as a control factor. It is possible to increase the pressure to a refrigerant state where the efficiency of heat dissipation by the radiator (12) is suitable regardless of the state of the refrigerant sucked into the fan.

また、請求項５に記載の発明では、圧縮機（１１）から吐出される冷媒の温度を検出する吐出冷媒温度検出手段（９１）を備え、制御手段（１００）は、吐出冷媒温度検出手段（９１）が検出した冷媒温度に基づいて、第１減圧手段（１３ａ）および第２減圧手段（２３）のうち一方の減圧量を制御することを特徴としている。 Further, the invention according to claim 5 is provided with discharge refrigerant temperature detection means (91) for detecting the temperature of the refrigerant discharged from the compressor (11), and the control means (100) is configured to detect the discharge refrigerant temperature detection means ( 91), the pressure reduction amount of one of the first pressure reduction means (13a) and the second pressure reduction means (23) is controlled on the basis of the refrigerant temperature detected by 91).

これによると、圧縮機（１１）の出口冷媒温度を制御因子とすることで、圧縮機（１１）の耐熱温度を超えることなく運転させることが可能であり、圧縮機の寿命低下を抑止することができる。 According to this, by setting the outlet refrigerant temperature of the compressor (11) as a control factor, it is possible to operate without exceeding the heat resistant temperature of the compressor (11), and to suppress a reduction in the life of the compressor. Can do.

また、請求項６に記載の発明では、第１蒸発器（１４）内を流れる冷媒の圧力を検出する第１蒸発器冷媒圧力検出手段と、第２蒸発器（２４）内を流れる冷媒の圧力を検出する第２蒸発器冷媒圧力検出手段と、を備え、制御手段（１００）は、第１蒸発器冷媒圧力検出手段が検出した冷媒圧力と第２蒸発器冷媒圧力手段が検出した冷媒圧力と差に基づいて、第１減圧手段（１３ａ）および第２減圧手段（２３）のうち他方の減圧量を制御することを特徴としている。 In the invention according to claim 6 , the first evaporator refrigerant pressure detecting means for detecting the pressure of the refrigerant flowing in the first evaporator (14) and the pressure of the refrigerant flowing in the second evaporator (24). And a control means (100) for detecting the refrigerant pressure detected by the first evaporator refrigerant pressure detecting means and the refrigerant pressure detected by the second evaporator refrigerant pressure detecting means. Based on the difference, the other pressure reduction amount of the first pressure reduction means (13a) and the second pressure reduction means (23) is controlled.

これによると、第１蒸発器（１４）内の冷媒圧力と第２蒸発器（２４）内の冷媒圧力とを直接検知して、正確な冷媒の圧力差に基づいて、第１減圧手段（１３ａ）および第２減圧手段（２３）のうち他方の減圧量を制御することができる。 According to this, the refrigerant pressure in the first evaporator (14) and the refrigerant pressure in the second evaporator (24) are directly detected, and based on the accurate refrigerant pressure difference, the first pressure reducing means (13a ) And the second decompression means (23), the other decompression amount can be controlled.

また、請求項７に記載の発明では、第１蒸発器（１４）内を流れる冷媒の温度を検出する第１蒸発器冷媒温度検出手段（９３）と、第２蒸発器（２４）内を流れる冷媒の温度を検出する第２蒸発器冷媒温度検出手段（９４）と、を備え、制御手段（１００）は、第１蒸発器冷媒温度検出手段（９３）が検出した冷媒温度と第２蒸発器冷媒温度検出手段（９４）が検出した冷媒温度と差を圧力差に関連する物理量とし、第１減圧手段（１３ａ）および第２減圧手段（２３）のうち他方の減圧量を制御することを特徴としている。 In the seventh aspect of the invention, the first evaporator refrigerant temperature detecting means (93) for detecting the temperature of the refrigerant flowing in the first evaporator (14) and the second evaporator (24) flow. Second evaporator refrigerant temperature detecting means (94) for detecting the temperature of the refrigerant, and the control means (100) includes the refrigerant temperature detected by the first evaporator refrigerant temperature detecting means (93) and the second evaporator. The difference between the refrigerant temperature detected by the refrigerant temperature detection means (94) is used as a physical quantity related to the pressure difference, and the other pressure reduction amount of the first pressure reduction means (13a) and the second pressure reduction means (23) is controlled. It is said.

これによると、比較的安価な手段により圧力差に関連する物理量である冷媒温度差を検知し、これに基づいて第１減圧手段（１３ａ）および第２減圧手段（２３）のうち他方の減圧量を制御することができる。 According to this, the refrigerant temperature difference, which is a physical quantity related to the pressure difference, is detected by a relatively inexpensive means, and based on this, the pressure reduction amount of the other of the first pressure reducing means (13a) and the second pressure reducing means (23) is detected. Can be controlled.

また、請求項８に記載の発明では、
制御手段（１００）は、
圧縮機（１１）の運転を開始した直後から、第１減圧手段（１３ａ）の減圧量および第２減圧手段（２３）の減圧量を、圧縮機（１１）から吐出され第１、第２減圧手段（１３ａ、２３）で減圧される前の冷媒の圧力もしくは温度に基づいて制御し、
圧縮機（１１）から吐出され第１、第２減圧手段（１３ａ、２３）で減圧される前の冷媒の圧力もしくは温度が所定値に到達した後は、第１減圧手段（１３ａ）および第２減圧手段（２３）のうち一方の減圧量を、圧縮機（１１）から吐出され第１、第２減圧手段（１３ａ、２３）で減圧される前の冷媒の圧力もしくは温度に基づいて制御し、第１減圧手段（１３ａ）および第２減圧手段（２３）のうち他方の減圧量を、第１蒸発器（１４）内の冷媒と第２蒸発器（２４）内の冷媒との圧力差、もしくは圧力差に関連する物理量に基づいて制御することを特徴としている。 In the invention according to claim 8 ,
The control means (100)
Immediately after starting the operation of the compressor (11), the reduced pressure amount of the first decompression means (13a) and the decompression amount of the second decompression means (23) are discharged from the compressor (11) and the first and second decompression pressures. Control based on the pressure or temperature of the refrigerant before being depressurized by the means (13a, 23),
After the pressure or temperature of the refrigerant discharged from the compressor (11) and before being depressurized by the first and second decompression means (13a, 23) reaches a predetermined value, the first decompression means (13a) and the second decompression means (13a) The pressure reduction amount of one of the pressure reducing means (23) is controlled based on the pressure or temperature of the refrigerant discharged from the compressor (11) before being reduced in pressure by the first and second pressure reducing means (13a, 23), The pressure reduction amount of the other of the first decompression means (13a) and the second decompression means (23) is set to the pressure difference between the refrigerant in the first evaporator (14) and the refrigerant in the second evaporator (24), or The control is based on a physical quantity related to the pressure difference.

これによると、圧縮機（１１）の運転が開始されて、圧縮機（１１）から吐出され第１、第２減圧手段（１３ａ、２３）で減圧される前の冷媒の圧力もしくは温度、すなわち高圧側冷媒の圧力もしくは温度が所定値に到達するまでは、高圧側冷媒の圧力もしくは温度を両減圧手段（１３ａ、２３）の制御因子として高圧側圧力の上昇速度を高め、速やかに効率のよい運転状態へ移行することができる。 According to this, the operation of the compressor (11) is started, and the pressure or temperature of the refrigerant before being discharged from the compressor (11) and decompressed by the first and second decompression means (13a, 23), that is, the high pressure. Until the pressure or temperature of the high-pressure side refrigerant reaches a predetermined value, the pressure or temperature of the high-pressure side refrigerant is used as a control factor for both decompression means (13a, 23) to increase the rate of increase of the high-pressure side pressure and to quickly and efficiently operate. You can transition to the state.

また、請求項９に記載の発明では、
制御手段（１００）は、
放熱器（１２）へ流入する外部流体の温度、放熱器（１２）から流出する外部流体の温度、第１蒸発器（１４）へ流入する外部流体の温度、および、第１蒸発器（１４）へ流入する外部流体の湿度の少なくともいずれかの変化に応じて、圧縮機（１１）から吐出され第１、第２減圧手段（１３ａ、２３）で減圧される前の冷媒の圧力もしくは温度を変更する場合には、
圧縮機（１１）から吐出され第１、第２減圧手段（１３ａ、２３）で減圧される前の冷媒の圧力もしくは温度が所定値に到達する前は、第１減圧手段（１３ａ）の減圧量および第２減圧手段（２３）の減圧量を、圧縮機（１１）から吐出され第１、第２減圧手段（１３ａ、２３）で減圧される前の冷媒の圧力もしくは温度に基づいて制御し、
圧縮機（１１）から吐出され第１、第２減圧手段（１３ａ、２３）で減圧される前の冷媒の圧力もしくは温度が所定値に到達した後は、第１減圧手段（１３ａ）および第２減圧手段（２３）のうち一方の減圧量を、圧縮機（１１）から吐出され第１、第２減圧手段（１３ａ、２３）で減圧される前の冷媒の圧力もしくは温度に基づいて制御し、第１減圧手段（１３ａ）および第２減圧手段（２３）のうち他方の減圧量を、第１蒸発器（１４）内の冷媒と第２蒸発器（２４）内の冷媒との圧力差、もしくは圧力差に関連する物理量に基づいて制御することを特徴としている。 In the invention according to claim 9 ,
The control means (100)
The temperature of the external fluid flowing into the radiator (12), the temperature of the external fluid flowing out of the radiator (12), the temperature of the external fluid flowing into the first evaporator (14), and the first evaporator (14) The pressure or temperature of the refrigerant before it is discharged from the compressor (11) and depressurized by the first and second depressurization means (13a, 23) is changed in accordance with a change in the humidity of the external fluid flowing into If you want to
Before the pressure or temperature of the refrigerant discharged from the compressor (11) and decompressed by the first and second decompression means (13a, 23) reaches a predetermined value, the decompression amount of the first decompression means (13a) And the amount of decompression of the second decompression means (23) is controlled based on the pressure or temperature of the refrigerant discharged from the compressor (11) and decompressed by the first and second decompression means (13a, 23),
After the pressure or temperature of the refrigerant discharged from the compressor (11) and before being depressurized by the first and second decompression means (13a, 23) reaches a predetermined value, the first decompression means (13a) and the second decompression means (13a) The pressure reduction amount of one of the pressure reducing means (23) is controlled based on the pressure or temperature of the refrigerant discharged from the compressor (11) before being reduced in pressure by the first and second pressure reducing means (13a, 23), The pressure reduction amount of the other of the first decompression means (13a) and the second decompression means (23) is set to the pressure difference between the refrigerant in the first evaporator (14) and the refrigerant in the second evaporator (24), or The control is based on a physical quantity related to the pressure difference.

これによると、放熱器（１２）、第１蒸発器（１４）、第２蒸発器（２４）の少なくともいずれかの環境条件の変化に応じて高圧側の冷媒の圧力もしくは温度を変更する場合には、高圧側冷媒の圧力もしくは温度が所定値に到達するまでは、高圧側冷媒の圧力もしくは温度を両減圧手段（１３ａ、２３）の制御因子として過渡状態の時間を短縮し、速やかに効率のよい運転状態へ移行することができる。 According to this, when the pressure or temperature of the refrigerant on the high pressure side is changed in accordance with a change in the environmental conditions of at least one of the radiator (12), the first evaporator (14), and the second evaporator (24). Until the pressure or temperature of the high-pressure side refrigerant reaches a predetermined value, the pressure or temperature of the high-pressure side refrigerant is used as a control factor for both decompression means (13a, 23) to shorten the time of the transient state and quickly increase the efficiency. It is possible to shift to a good operating state.

なお、上記各手段に付した括弧内の符号は、後述する実施形態記載の具体的手段との対応関係を示す一例である。 In addition, the code | symbol in the parenthesis attached | subjected to each said means is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

以下、本発明の実施の形態を図に基づいて説明する。 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

（第１の実施形態）
図１は、本発明を適用した第１の実施形態における蒸気圧縮式の冷凍サイクル１を示す模式構成図である。本実施形態では、冷凍サイクル１をヒートポンプ式給湯装置に適用した例を示す。 (First embodiment)
FIG. 1 is a schematic configuration diagram showing a vapor compression refrigeration cycle 1 in a first embodiment to which the present invention is applied. In the present embodiment, an example in which the refrigeration cycle 1 is applied to a heat pump type hot water supply apparatus is shown.

本実施形態の冷凍サイクル１では、冷媒を吸入圧縮する圧縮機１１の冷媒吐出側には放熱器１２が配置されている。本実施形態の放熱器１２は水冷媒熱交換器であって、圧縮機１１から吐出された高圧冷媒が流通する冷媒通路１２ａと水が流通する水通路１２ｂとを備えており、対向して流れる高圧冷媒と水（放熱器における外部流体）との熱交換を行って、高圧冷媒を冷却し水を湯に沸き上げるようになっている。 In the refrigeration cycle 1 of the present embodiment, a radiator 12 is disposed on the refrigerant discharge side of a compressor 11 that sucks and compresses refrigerant. The radiator 12 of the present embodiment is a water-refrigerant heat exchanger, and includes a refrigerant passage 12a through which high-pressure refrigerant discharged from the compressor 11 circulates and a water passage 12b through which water circulates, and flows oppositely. Heat exchange is performed between the high-pressure refrigerant and water (external fluid in the radiator), thereby cooling the high-pressure refrigerant and boiling water into hot water.

ここで、冷凍サイクル１の冷媒として、通常のフロン系冷媒を用いる場合は、高圧圧力が臨界圧力を超えない亜臨界サイクルとなるので、放熱器１２は冷媒を凝縮する凝縮器として作用する。一方、冷媒として二酸化炭素（ＣＯ₂）のように高圧圧力が臨界圧力を超える冷媒を用いる場合は冷凍サイクル１が超臨界サイクルとなるので、冷媒は超臨界状態のまま放熱し凝縮しない。 Here, when a normal chlorofluorocarbon refrigerant is used as the refrigerant of the refrigeration cycle 1, since the high pressure is a subcritical cycle in which the critical pressure is not exceeded, the radiator 12 acts as a condenser for condensing the refrigerant. On the other hand, when a refrigerant whose high pressure exceeds the critical pressure, such as carbon dioxide (CO ₂ ), is used as the refrigerant, the refrigeration cycle 1 becomes a supercritical cycle.

放熱器１２よりもさらに冷媒流れ下流側部位には、エジェクタ１３が配置されている。このエジェクタ１３は冷媒を減圧する減圧手段であるとともに、高速で噴出する冷媒流の吸引作用（巻き込み作用）によって冷媒の循環を行なう冷媒循環手段（運動量輸送式ポンプ）でもある。 An ejector 13 is disposed further downstream of the refrigerant flow than the radiator 12. The ejector 13 is a decompression means for decompressing the refrigerant, and is also a refrigerant circulation means (momentum transport pump) that circulates the refrigerant by a suction action (contraction action) of a refrigerant flow ejected at high speed.

エジェクタ１３には、第１放熱器１２から流入する高圧冷媒の通路面積を小さく絞って、高圧冷媒を等エントロピ的に減圧膨張させるノズル部１３ａと、ノズル部１３ａの冷媒噴出口と同一空間に配置され、後述する第２蒸発器２４からの気相冷媒を吸引する冷媒吸引口１３ｂが備えられている。 The ejector 13 is arranged in the same space as the nozzle portion 13a for reducing the passage area of the high-pressure refrigerant flowing from the first radiator 12 to be isentropically decompressed and expanded, and the refrigerant outlet of the nozzle portion 13a. A refrigerant suction port 13b for sucking a gas-phase refrigerant from the second evaporator 24, which will be described later, is provided.

本実施形態におけるエジェクタ１３のノズル部１３ａは、ノズル開度を可変して減圧量を調節できる可変ノズルであり、ステッピングモータ等の駆動手段によりニードル弁体等を駆動してノズル開度を調整できるようになっている。ノズル部１３ａは本実施形態における第１減圧手段である。 The nozzle portion 13a of the ejector 13 in the present embodiment is a variable nozzle that can adjust the amount of pressure reduction by varying the nozzle opening, and can adjust the nozzle opening by driving the needle valve body or the like by a driving means such as a stepping motor. It is like that. The nozzle part 13a is the first pressure reducing means in this embodiment.

ノズル部１３ａおよび冷媒吸引口１３ｂの冷媒流れ下流側部位には、ノズル部１３ａからの高速度の冷媒流と冷媒吸引口１３ｂの吸引冷媒とを混合する混合部１３ｃが設けられている。 A mixing unit 13c that mixes the high-speed refrigerant flow from the nozzle unit 13a and the suction refrigerant from the refrigerant suction port 13b is provided at the downstream side of the refrigerant flow of the nozzle unit 13a and the refrigerant suction port 13b.

そして、混合部１３ｃの冷媒流れ下流側にディフューザ部１３ｄが配置されている。このディフューザ部１３ｄは冷媒の通路面積を徐々に大きくする形状に形成されており、冷媒流れを減速して冷媒圧力を上昇させる作用、つまり、冷媒の速度エネルギーを圧力エネルギーに変換する作用を果たす。 And the diffuser part 13d is arrange | positioned in the refrigerant | coolant flow downstream of the mixing part 13c. The diffuser portion 13d is formed in a shape that gradually increases the refrigerant passage area, and acts to decelerate the refrigerant flow to increase the refrigerant pressure, that is, to convert the velocity energy of the refrigerant into pressure energy.

なお、本実施形態のエジェクタ１３では、混合部１３ｃも冷媒の通路面積を徐々に大きくする形状に形成されており、混合部１３ｃとディフューザ部１３ｄとからなる構成が本実施形態のエジェクタ１３における昇圧部である。 Note that in the ejector 13 of the present embodiment, the mixing portion 13c is also formed in a shape that gradually increases the passage area of the refrigerant, and the configuration composed of the mixing portion 13c and the diffuser portion 13d is a pressure increase in the ejector 13 of the present embodiment. Part.

エジェクタ１３のディフューザ部１３ｄの下流側に第１蒸発器１４が接続され、この第１蒸発器１４の冷媒流れ下流側は圧縮機１１の吸入側に接続されている。圧縮機１１、放熱器１２、エジェクタ１３、および第１蒸発器１４は、冷媒循環通路（環状通路に相当）１０により環状に接続されている。 The first evaporator 14 is connected to the downstream side of the diffuser portion 13 d of the ejector 13, and the refrigerant flow downstream side of the first evaporator 14 is connected to the suction side of the compressor 11. The compressor 11, the radiator 12, the ejector 13, and the first evaporator 14 are annularly connected by a refrigerant circulation passage (corresponding to an annular passage) 10.

そして、この冷媒循環通路１０の放熱器１２下流側かつエジェクタ１３上流側にある分岐点ＺＺから冷媒分岐通路（分岐通路に相当）２０が分岐されており、この冷媒分岐通路２０の下流端はエジェクタ１３の冷媒吸引口１３ｂに接続されている。 A refrigerant branch passage (corresponding to a branch passage) 20 is branched from a branch point ZZ downstream of the radiator 12 and upstream of the ejector 13 of the refrigerant circulation passage 10, and the downstream end of the refrigerant branch passage 20 is an ejector. 13 refrigerant suction ports 13b.

この冷媒分岐通路２０には、分岐点ＺＺ下流側直後に第２減圧手段である膨張弁２３が配置され、この膨張弁２３よりも冷媒流れ下流側部位には第２蒸発器２４が配置されている。本実施形態の膨張弁２３は電子膨張弁であり、開度調節を行うことで冷媒減圧量を調節できるようになっている。 In the refrigerant branch passage 20, an expansion valve 23 that is a second pressure reducing means is disposed immediately downstream of the branch point ZZ, and a second evaporator 24 is disposed in a portion downstream of the refrigerant flow from the expansion valve 23. Yes. The expansion valve 23 of the present embodiment is an electronic expansion valve, and the refrigerant decompression amount can be adjusted by adjusting the opening degree.

本実施形態では、２つの蒸発器１４、２４は例えば一体構造に組み付けられて、２つの蒸発器１４、２４を図示しない１つの室外機筐体内に収納するようになっている。そして、筐体内に構成される空気通路に図示しない共通のブロワ（電動送風機）により空気（両蒸発器における外部流体）を矢印ＡＡのごとく送風し、この送風空気から２つの蒸発器１４、２４で吸熱するようなっている。 In the present embodiment, the two evaporators 14 and 24 are assembled in, for example, an integrated structure so that the two evaporators 14 and 24 are accommodated in a single outdoor unit housing (not shown). Then, air (external fluid in both evaporators) is blown as indicated by an arrow AA by a common blower (electric blower) (not shown) in an air passage configured in the housing, and the two evaporators 14 and 24 are used to blow air from the blown air. It absorbs heat.

ここで、２つの蒸発器１４、２４のうち、エジェクタ１３下流側の冷媒循環通路１０に配設される第１蒸発器１４を空気流れＡＡの上流側に配置し、エジェクタ１３の冷媒吸引口１３ｂに接続される第２蒸発器２４を空気流れＡＡの下流側に配置している。 Here, of the two evaporators 14, 24, the first evaporator 14 disposed in the refrigerant circulation passage 10 downstream of the ejector 13 is disposed upstream of the air flow AA, and the refrigerant suction port 13b of the ejector 13 is disposed. The second evaporator 24 connected to is disposed downstream of the air flow AA.

本実施形態の冷凍サイクル１は、冷媒循環通路１０の圧縮機１１より下流側かつ放熱器１２より上流側に、圧縮機１１から吐出される冷媒の温度を検出する吐出冷媒温度検出手段としての吐出温度センサ９１を備えている。また、冷媒循環回路１０の放熱器１２より下流側かつエジェクタ１３より上流側（本例では分岐点ＺＺより上流側）に、冷凍サイクル１内の高圧側の冷媒圧力を検出する圧力検出手段としての圧力センサ９２を備えている。 The refrigeration cycle 1 of the present embodiment is a discharge refrigerant temperature detection unit that detects the temperature of refrigerant discharged from the compressor 11 downstream of the compressor 11 and upstream of the radiator 12 in the refrigerant circulation passage 10. A temperature sensor 91 is provided. Further, as pressure detection means for detecting the refrigerant pressure on the high pressure side in the refrigeration cycle 1 downstream of the radiator 12 and upstream of the ejector 13 (in this example, upstream of the branch point ZZ) of the refrigerant circulation circuit 10. A pressure sensor 92 is provided.

さらに、冷媒循環回路１０のエジェクタ１３より下流側かつ第１蒸発器１４より上流側に（すなわち第１蒸発器１４の冷媒入口側に）、第１蒸発器１４内を流れる冷媒の温度を検出する第１蒸発器冷媒温度検出手段としての第１蒸発器温度センサ９３を備えている。また、冷媒分岐回路２０の膨張弁２３より下流側かつ第２蒸発器２４より上流側に（すなわち第２蒸発器２４の冷媒入口側に）、第２蒸発器２４内を流れる冷媒の温度を検出する第２蒸発器冷媒温度検出手段としての第２蒸発器温度センサ９４を備えている。 Further, the temperature of the refrigerant flowing in the first evaporator 14 is detected downstream of the ejector 13 in the refrigerant circulation circuit 10 and upstream of the first evaporator 14 (that is, on the refrigerant inlet side of the first evaporator 14). A first evaporator temperature sensor 93 is provided as first evaporator refrigerant temperature detecting means. Further, the temperature of the refrigerant flowing in the second evaporator 24 is detected downstream of the expansion valve 23 of the refrigerant branch circuit 20 and upstream of the second evaporator 24 (that is, on the refrigerant inlet side of the second evaporator 24). The second evaporator temperature sensor 94 is provided as a second evaporator refrigerant temperature detecting means.

図１において符号１００を付した構成はヒートポンプ装置用の制御装置であって、制御装置１００は本実施形態における制御手段である。 1 is a control device for a heat pump device, and the control device 100 is a control means in this embodiment.

制御装置１００は、各温度センサ９１、９３、９４からの温度情報や圧力センサ９２からの圧力情報、放熱器１２の外部流体流入温度（熱交換前温度）である給水温度、放熱器１２の外部流体流出温度（熱交換後温度）である沸き上げ温度、両蒸発器１４、２４の外部流体流入温度（熱交換前温度）である外気温度、図示しない操作盤に設けられたスイッチかたの信号等に基づいて、圧縮機１１、エジェクタ１３のノズル部１３ａ、膨張弁２３、ブロワ等を作動制御するようになっている。 The control device 100 includes temperature information from each temperature sensor 91, 93, 94, pressure information from the pressure sensor 92, a feed water temperature that is an external fluid inflow temperature (temperature before heat exchange) of the radiator 12, and an outside of the radiator 12. Boiling temperature which is fluid outflow temperature (temperature after heat exchange), outside air temperature which is external fluid inflow temperature (temperature before heat exchange) of both evaporators 14 and 24, a signal from a switch provided on an operation panel (not shown) Based on the above, the operation of the compressor 11, the nozzle portion 13a of the ejector 13, the expansion valve 23, the blower, and the like is controlled.

次に、上記構成に基づき、本実施形態の冷凍サイクル１の作動について説明する。 Next, based on the said structure, the action | operation of the refrigerating cycle 1 of this embodiment is demonstrated.

図２は、制御装置１００の概略制御動作を示すフローチャートである。 FIG. 2 is a flowchart showing a schematic control operation of the control device 100.

制御装置１００は、まず、外気温度等に基づいて決定される冷媒吐出量となるように圧縮機１１の運転を開始し、圧力センサ９２が検出する高圧側圧力が給水温度等に基づいて決定される圧力目標値に近づくように、エジェクタ１３のノズル部１３ａの開度（すなわち減圧量）を調節する（ステップ１１０）とともに、膨張弁２３の開度（すなわち減圧量）を調節する（ステップ１２０）。 First, the control device 100 starts the operation of the compressor 11 so that the refrigerant discharge amount is determined based on the outside air temperature or the like, and the high pressure side pressure detected by the pressure sensor 92 is determined based on the feed water temperature or the like. The opening (that is, the amount of pressure reduction) of the nozzle portion 13a of the ejector 13 is adjusted (step 110) and the opening (ie, the amount of pressure reduction) of the expansion valve 23 is adjusted (step 120) so as to approach the target pressure value. .

そして、圧力センサ９２が検出する高圧側圧力が所定値に到達したか否か判断し（ステップ１３０）、到達していない場合にはステップ１１０にリターンする。ここで、判定基準となる所定値は、例えば、圧力目標値が１０ＭＰａであるときには９５％値である９．５ＭＰａとすることができる。 Then, it is determined whether or not the high pressure side pressure detected by the pressure sensor 92 has reached a predetermined value (step 130), and if not, the process returns to step 110. Here, the predetermined value serving as the determination criterion can be, for example, 9.5 MPa which is a 95% value when the pressure target value is 10 MPa.

ステップ１３０において、圧力センサ９２が検出する高圧側圧力が所定値に到達したと判断した場合には、ステップ１１０と同様に、圧力センサ９２が検出する高圧側圧力が圧力目標値に一致するように、エジェクタ１３のノズル部１３ａの開度を調節し（ステップ１４０）、第１蒸発器冷媒温度センサ９３が検出した冷媒温度と第２蒸発器冷媒温度センサ９４が検出した冷媒温度と差が外気温度等に基づいて決定される温度差目標値に近づいて一致するように、膨張弁２３の開度を調節する（ステップ１５０）。 When it is determined in step 130 that the high-pressure side pressure detected by the pressure sensor 92 has reached a predetermined value, as in step 110, the high-pressure side pressure detected by the pressure sensor 92 matches the target pressure value. Then, the opening degree of the nozzle portion 13a of the ejector 13 is adjusted (step 140), and the difference between the refrigerant temperature detected by the first evaporator refrigerant temperature sensor 93 and the refrigerant temperature detected by the second evaporator refrigerant temperature sensor 94 is the outside air temperature. The opening degree of the expansion valve 23 is adjusted so as to approach and coincide with the temperature difference target value determined based on the above (step 150).

すなわち、圧縮機１１の運転を開始した直後から高圧側圧力が所定値に到達するまでは、両減圧手段であるノズル部１３ａ、膨張弁２３による減圧量を高圧側圧力に基づいて制御し、高圧側圧力が所定値に到達した後は、一方の減圧手段であるノズル部１３ａによる減圧量を、高圧側圧力に基づく制御としたまま、他方の減圧手段である膨張弁２３による減圧量を、第１蒸発器１４内の冷媒と第２蒸発器２４内の冷媒との温度差に基づいて制御する。そして、この制御を運転終了まで継続する。 That is, immediately after the operation of the compressor 11 is started and until the high-pressure side pressure reaches a predetermined value, the amount of pressure reduction by the nozzle part 13a and the expansion valve 23, which are both decompression means, is controlled based on the high-pressure side pressure. After the side pressure reaches a predetermined value, the pressure reduction amount by the expansion valve 23 as the other pressure reducing means is changed to the first pressure reduction means while the pressure reduction amount by the nozzle portion 13a as the pressure reducing means is controlled based on the high pressure side pressure. Control is performed based on the temperature difference between the refrigerant in the first evaporator 14 and the refrigerant in the second evaporator 24. This control is continued until the end of operation.

上述した制御装置１００の制御動作により冷凍サイクル１が運転されているときには、図１に示す第１蒸発器１４から流出したガス状冷媒が圧縮機１１に吸入圧縮される。 When the refrigeration cycle 1 is operated by the control operation of the control device 100 described above, the gaseous refrigerant flowing out from the first evaporator 14 shown in FIG.

そして、圧縮機１１で圧縮され吐出された高温高圧状態の冷媒は放熱器１２に流入する。放熱器１２では高温の冷媒が水と熱交換により冷却され、放熱器１２から流出した高圧冷媒は、分岐点ＺＺで分配されエジェクタ１３と膨張弁２３に向かって流れる。 The high-temperature and high-pressure refrigerant compressed and discharged by the compressor 11 flows into the radiator 12. In the radiator 12, the high-temperature refrigerant is cooled by exchanging heat with water, and the high-pressure refrigerant flowing out of the radiator 12 is distributed at the branch point ZZ and flows toward the ejector 13 and the expansion valve 23.

放熱器１２から流出した冷媒の一部は膨張弁２３で減圧されて低圧冷媒となり、この低圧冷媒が第２蒸発器２４に流入する。第２蒸発器２４内では、矢印ＡＡ方向に外部を流れる送風空気から冷媒が吸熱して蒸発する。 Part of the refrigerant flowing out of the radiator 12 is decompressed by the expansion valve 23 to become low-pressure refrigerant, and this low-pressure refrigerant flows into the second evaporator 24. In the second evaporator 24, the refrigerant absorbs heat from the blown air flowing outside in the direction of arrow AA and evaporates.

放熱器１２から流出してエジェクタ１３に流入した冷媒流れはノズル部１３ａで減圧され膨張する。従って、ノズル部１３ａで冷媒の圧力エネルギーが速度エネルギーに変換され、このノズル部１３ａの噴出口から冷媒は高速度の流れとなって噴出する。この際の冷媒圧力低下により、冷媒吸引口１３ｂから分岐冷媒通路２０の第２蒸発器２４通過後の冷媒を吸引する。 The refrigerant flow flowing out of the radiator 12 and flowing into the ejector 13 is decompressed and expanded by the nozzle portion 13a. Accordingly, the pressure energy of the refrigerant is converted into velocity energy by the nozzle portion 13a, and the refrigerant is ejected from the jet port of the nozzle portion 13a as a high-speed flow. Due to the refrigerant pressure drop at this time, the refrigerant after passing through the second evaporator 24 in the branch refrigerant passage 20 is sucked from the refrigerant suction port 13b.

ノズル部１３ａから噴出した冷媒と冷媒吸引口１３ｂから吸引された冷媒は、ノズル部１３ａ下流側の混合部１３ｃで混合してディフューザ部１３ｄに流入する。このディフューザ部１３ｄでは通路面積の拡大により、冷媒の速度（膨張）エネルギーが圧力エネルギーに変換されるため、冷媒の圧力が上昇する。 The refrigerant ejected from the nozzle portion 13a and the refrigerant sucked from the refrigerant suction port 13b are mixed in the mixing portion 13c on the downstream side of the nozzle portion 13a and flow into the diffuser portion 13d. In the diffuser portion 13d, the passage area is enlarged, so that the speed (expansion) energy of the refrigerant is converted into pressure energy, so that the pressure of the refrigerant rises.

そして、エジェクタ１３のディフューザ部１３ｄから流出した冷媒は第１蒸発器１４に流入する。第１蒸発器１４内を流れる低温の低圧冷媒は、矢印ＡＡ方向に外部を流れる送風空気から吸熱して蒸発する。第１蒸発器１４内で蒸発した後の気相冷媒は圧縮機１１に再び吸入圧縮される。 Then, the refrigerant that has flowed out of the diffuser portion 13 d of the ejector 13 flows into the first evaporator 14. The low-temperature low-pressure refrigerant flowing in the first evaporator 14 absorbs heat from the blown air flowing outside in the arrow AA direction and evaporates. The vapor-phase refrigerant that has evaporated in the first evaporator 14 is again sucked and compressed by the compressor 11.

エジェクタ１３の昇圧部において冷媒圧力が昇圧されるので、第１蒸発器１４内の冷媒蒸発圧力（冷媒蒸発温度）よりも第２蒸発器２４内の冷媒蒸発圧力（冷媒蒸発温度）を低くすることができる。 Since the refrigerant pressure is boosted in the boosting section of the ejector 13, the refrigerant evaporation pressure (refrigerant evaporation temperature) in the second evaporator 24 is made lower than the refrigerant evaporation pressure (refrigerant evaporation temperature) in the first evaporator 14. Can do.

そして、送風空気の流れ方向ＡＡに対して冷媒蒸発温度が高い第１蒸発器１４を上流側に配置し、冷媒蒸発温度が低い第２蒸発器２４を下流側に配置しているので、第１蒸発器１４における冷媒蒸発温度と送風空気との温度差および第２蒸発器２４における冷媒蒸発温度と送風空気との温度差を両方とも確保し易い。 And since the 1st evaporator 14 with a high refrigerant | coolant evaporation temperature is arrange | positioned in the upstream with respect to the flow direction AA of blowing air, and the 2nd evaporator 24 with a low refrigerant | coolant evaporation temperature is arrange | positioned in the downstream, the 1st It is easy to ensure both the temperature difference between the refrigerant evaporation temperature and the blown air in the evaporator 14 and the temperature difference between the refrigerant evaporation temperature and the blown air in the second evaporator 24.

このため、第１、第２蒸発器１４、２４の吸熱性能を両方とも有効に発揮できる。また、混合部１３ｃ、ディフューザ部１３ｄでの昇圧作用により圧縮機１１の吸入圧を上昇して、圧縮機１１の駆動動力を低減することができる。 For this reason, both the heat absorption performance of the 1st, 2nd evaporators 14 and 24 can be exhibited effectively. Further, the suction pressure of the compressor 11 can be increased by the pressure increasing action in the mixing unit 13c and the diffuser unit 13d, and the driving power of the compressor 11 can be reduced.

上述の構成および作動によれば、制御装置１００は、運転を開始し高圧側圧力が所定圧に到達した後は、エジェクタ１３のノズル部１３ａの減圧量を高圧側圧力に基づいて制御し、膨張弁２３の減圧量を第１蒸発器１４内の冷媒と第２蒸発器２４内の冷媒との温度差に基づいて制御している。 According to the above-described configuration and operation, the control device 100 starts the operation and, after the high-pressure side pressure reaches the predetermined pressure, controls the pressure reduction amount of the nozzle portion 13a of the ejector 13 based on the high-pressure side pressure, and expands. The pressure reduction amount of the valve 23 is controlled based on the temperature difference between the refrigerant in the first evaporator 14 and the refrigerant in the second evaporator 24.

これにより、圧縮機１１から吐出されノズル部１３ａおよび膨張弁２３で減圧される前の冷媒の圧力や温度等の状態、すなわち高圧側の冷媒状態（例えば圧縮機１１出口冷媒温度、放熱器１２下流側圧力）を、放熱器１２における放熱の効率が最適となる冷媒状態とすることができる。さらに、第１蒸発器１４内の冷媒と第２蒸発器２４内の冷媒との温度差を、空気流れ方向ＡＡに並設された第１蒸発器１４、第２蒸発器２４において着霜を抑制して外部流体から吸熱する効率が良好な温度差とすることができる。また、第１蒸発器１４内の冷媒と第２蒸発器２４内の冷媒との圧力差を、エジェクタ１３の昇圧効果によって熱移送の効率が最適となるように調整することができる。 Thereby, the state of the refrigerant such as the pressure and temperature of the refrigerant discharged from the compressor 11 and decompressed by the nozzle portion 13a and the expansion valve 23, that is, the refrigerant state on the high pressure side (for example, the refrigerant temperature at the outlet of the compressor 11 and downstream of the radiator 12). Side pressure) can be set to a refrigerant state in which the efficiency of heat dissipation in the radiator 12 is optimal. Further, the temperature difference between the refrigerant in the first evaporator 14 and the refrigerant in the second evaporator 24 is used to suppress frost formation in the first evaporator 14 and the second evaporator 24 arranged in parallel in the air flow direction AA. Thus, the efficiency of absorbing heat from the external fluid can be made a good temperature difference. Further, the pressure difference between the refrigerant in the first evaporator 14 and the refrigerant in the second evaporator 24 can be adjusted so that the efficiency of heat transfer is optimized by the boosting effect of the ejector 13.

本実施形態の冷凍サイクル１のように、エジェクタ１３を採用した場合には、圧縮機１１の吸入圧力を第１蒸発器１４と同じ水準にすることができるので、第１、第２蒸発器１４、２４の吸熱能力を保ったまま、圧縮機１１の負荷を低減させることで運転効率を改善することができる。 When the ejector 13 is employed as in the refrigeration cycle 1 of the present embodiment, the suction pressure of the compressor 11 can be set to the same level as that of the first evaporator 14, and thus the first and second evaporators 14 are used. The operation efficiency can be improved by reducing the load on the compressor 11 while maintaining the heat absorption capacity of 24.

エジェクタ１３が上昇させる冷媒流の圧力、すなわち昇圧量は、エジェクタ１３の駆動流れの流量（ノズル部１３ａを通過する冷媒流量）や、冷媒吸引口１３ｂに吸引される冷媒状態に大きく左右される。 The pressure of the refrigerant flow raised by the ejector 13, that is, the amount of pressure increase, depends greatly on the flow rate of the drive flow of the ejector 13 (the flow rate of the refrigerant passing through the nozzle portion 13 a) and the refrigerant state sucked into the refrigerant suction port 13 b.

例えば、蒸発温度が高い条件下（すなわち第２蒸発器２４に流れる風の温度が高い条件下）では、第２蒸発器２４出口の冷媒は完全に気体であり、密度が小さいので比較的昇圧量が大きくなる。一方、蒸発温度が低い条件下（すなわち第２蒸発器２４に流れる風の温度が低い条件下）では第２蒸発器２４出口の冷媒は湿り状態（液相冷媒を含む状態）で密度が大きいため昇圧量は小さくなる。したがって、各条件によってエジェクタ１３による昇圧量を調整し最も効率のよい状態することが望ましい。 For example, under a condition where the evaporation temperature is high (that is, a condition where the temperature of the wind flowing through the second evaporator 24 is high), the refrigerant at the outlet of the second evaporator 24 is completely a gas, and since the density is small, the pressure increase amount is relatively high. Becomes larger. On the other hand, under conditions where the evaporation temperature is low (that is, conditions where the temperature of the wind flowing through the second evaporator 24 is low), the refrigerant at the outlet of the second evaporator 24 has a high density in a wet state (including a liquid phase refrigerant). The amount of pressure increase becomes small. Therefore, it is desirable to adjust the boosting amount by the ejector 13 according to each condition so as to obtain the most efficient state.

図１に示すサイクル構成では、第１蒸発器１４、第２蒸発器２４の蒸発温度差は昇圧量とほぼ比例関係にあるから、蒸発温度差を調整することで最適な昇圧量とすることが可能となる。 In the cycle configuration shown in FIG. 1, since the evaporation temperature difference between the first evaporator 14 and the second evaporator 24 is substantially proportional to the pressure increase amount, the optimum pressure increase amount can be obtained by adjusting the evaporation temperature difference. It becomes possible.

本実施形態によれば、エジェクタ１３のノズル部１３ａの開度制御の制御因子を高圧側冷媒状態とし、膨張弁２３の開度制御の制御因子を蒸発温度差とすることで、放熱器１２の放熱性能が最も効率のよいように高圧側の冷媒状態（例えば圧縮機出口温度、放熱器下流圧力）を調整でき、かつ第１、第２蒸発器１４、２４の蒸発温度水準を望ましい状態、すなわちエジェクタの昇圧効果が最も効率のよい状態に調整することができる。したがって、冷凍サイクル１の効率を確実に向上することができる。 According to the present embodiment, the control factor for the opening degree control of the nozzle portion 13a of the ejector 13 is set to the high-pressure side refrigerant state, and the control factor for the opening degree control of the expansion valve 23 is set to the evaporation temperature difference. The refrigerant state on the high pressure side (for example, the compressor outlet temperature, the radiator downstream pressure) can be adjusted so that the heat dissipation performance is most efficient, and the evaporation temperature level of the first and second evaporators 14 and 24 is desirable. The boosting effect of the ejector can be adjusted to the most efficient state. Therefore, the efficiency of the refrigeration cycle 1 can be improved reliably.

なお、ステップ１５０を実行する際には、蒸発温度差の目標値を、運転環境条件すなわち放熱器１２、第１蒸発器１４、第２蒸発器２４の少なくともいずれかの環境条件、例えば、外気温度（第１、第２蒸発器へ流入する外部流体の温度）や給水温度（放熱器へ流入する外部流体の温度）等に応じて、目標値を変更するものであってもよい。図３は、蒸発温度の目標値を外気温度に応じて変更する例を示している。 When step 150 is executed, the target value of the evaporation temperature difference is set to the operating environment condition, that is, the environmental condition of at least one of the radiator 12, the first evaporator 14, and the second evaporator 24, for example, the outside air temperature. The target value may be changed according to (temperature of the external fluid flowing into the first and second evaporators), feed water temperature (temperature of the external fluid flowing into the radiator), and the like. FIG. 3 shows an example in which the target value of the evaporation temperature is changed according to the outside air temperature.

これによると、放熱器１２、第１蒸発器１４、第２蒸発器２４の外部流体の温度や、第１蒸発器１４、第２蒸発器２４の着霜状態等の環境条件が変化した場合であっても、良好な第１蒸発器１４内の冷媒と第２蒸発器２４内の冷媒との温度差を確保しつつ運転することができる。 According to this, when the environmental conditions such as the temperature of the external fluid of the radiator 12, the first evaporator 14, and the second evaporator 24 and the frosting state of the first evaporator 14 and the second evaporator 24 have changed. Even if it exists, it can drive | operate, ensuring the temperature difference with the favorable refrigerant | coolant in the 1st evaporator 14, and the refrigerant | coolant in the 2nd evaporator 24. FIG.

また、第１蒸発器１４、第２蒸発器２４の少なくともいずれかの外表面温度に応じて、目標値を変更するものであってもよい。これによると、第１蒸発器１４、第２蒸発器２４に着霜が始まり外表面の温度低下が発生した場合、すなわち着霜が進行し易い条件となった場合には、第１蒸発器１４と第２蒸発器２４との冷媒温度差を拡大することで、第２蒸発器２４に対する第１蒸発器１４の温度が高くなるように両蒸発器１４、２４の温度差を大きくし、着霜を抑制することができる。 Further, the target value may be changed according to the outer surface temperature of at least one of the first evaporator 14 and the second evaporator 24. According to this, when frosting starts on the first evaporator 14 and the second evaporator 24 and a temperature drop of the outer surface occurs, that is, when the frosting is likely to proceed, the first evaporator 14 By increasing the refrigerant temperature difference between the second evaporator 24 and the second evaporator 24, the temperature difference between the evaporators 14 and 24 is increased so that the temperature of the first evaporator 14 with respect to the second evaporator 24 increases, and frost formation is achieved. Can be suppressed.

また、制御装置１００は、運転を開始してから高圧側圧力が所定圧に到達するまでは、ステップ１１０、１２０を実行することで、エジェクタ１３のノズル部１３ａの減圧量および膨張弁２３の減圧量をともに高圧側圧力に基づいて制御している。したがって、高圧側冷媒圧力が所定値に到達するまでは、高圧側冷媒の圧力を両減圧手段１３ａ、２３の制御因子として高圧側圧力の上昇速度を高め、速やかにステップ１４０、１５０による効率のよい運転状態へ移行することができる。 Further, the control device 100 executes steps 110 and 120 until the high-pressure side pressure reaches a predetermined pressure after the start of operation, thereby reducing the pressure reduction amount of the nozzle portion 13a of the ejector 13 and the pressure reduction of the expansion valve 23. Both quantities are controlled based on the high pressure side pressure. Therefore, until the high-pressure side refrigerant pressure reaches a predetermined value, the pressure of the high-pressure side refrigerant is used as a control factor for the decompression means 13a, 23 to increase the rate of increase of the high-pressure side pressure, and the steps 140 and 150 are efficient. It is possible to shift to the operating state.

これは、高圧側冷媒の状態の変化速度よりも蒸発器側の冷媒の変化速度の方が遅いため、高圧側冷媒の状態を大きく変化させる際には、蒸発温度差を制御因子とすると膨張弁２３の開度変更速度が遅くなり、高圧側圧力の上昇を阻害し、安定時の開度に到達するのに時間を要するためである。 This is because the change rate of the refrigerant on the evaporator side is slower than the change rate of the state of the high-pressure side refrigerant. Therefore, when changing the state of the high-pressure side refrigerant greatly, if the evaporation temperature difference is a control factor, the expansion valve This is because the opening degree changing speed of 23 is slowed, the increase in the high-pressure side pressure is hindered, and it takes time to reach the opening degree at the stable time.

なお、運転を開始してから高圧側圧力が所定圧に到達するまでの両減圧手段の制御は、高圧側圧力のみによらず、高圧側圧力を主たる制御因子とするのであれば、蒸発温度差等を制御因子に加えるものであってもよい。 Note that the control of both decompression means from the start of operation until the high-pressure side pressure reaches the predetermined pressure is not limited to the high-pressure side pressure, and if the high-pressure side pressure is the main control factor, the evaporation temperature difference Etc. may be added to the control factor.

上述したように、本実施形態では、運転開始時に両減圧手段の高圧側圧力に基づく制御を採用していたが、放熱器１２、第１蒸発器１４、第２蒸発器２４の少なくともいずれかの環境条件の変化に応じて、高圧側冷媒の圧力もしくは温度を変更する場合、例えば、給水温度（放熱器１２の外部流体の流入温度）、沸き上げ温度（放熱器１２の外部流体の流出温度）、外気温度（第１、第２蒸発器１４、２４の外部流体の流入温度）、外気湿度（第１、第２蒸発器１４、２４の外部流体の流入湿度）等の少なくともいずれかが大きく変化して、冷凍サイクル１の運転状態を大きく変更する場合にも、運転状態変更の過渡状態時に上記運転開始時と同様に両減圧手段の高圧側圧力に基づく制御を採用してもよい。 As described above, in the present embodiment, the control based on the high-pressure side pressures of both decompression means is employed at the start of operation, but at least one of the radiator 12, the first evaporator 14, and the second evaporator 24 is employed. When changing the pressure or temperature of the high-pressure side refrigerant according to changes in environmental conditions, for example, the feed water temperature (inflow temperature of the external fluid of the radiator 12), the boiling temperature (outflow temperature of the external fluid of the radiator 12), for example At least one of the outside air temperature (inflow temperature of the external fluid of the first and second evaporators 14 and 24), the outside air humidity (inflow humidity of the external fluid of the first and second evaporators 14 and 24), and the like greatly change. Even when the operating state of the refrigeration cycle 1 is greatly changed, control based on the high-pressure side pressures of both decompression means may be employed in the transient state of the operating state change as in the case of the start of the operation.

これによると、放熱器１２、第１蒸発器１４、第２蒸発器２４の少なくともいずれかの環境条件の変化に応じて高圧側の冷媒の圧力もしくは温度を変更する場合には、高圧側冷媒の圧力が所定値に到達するまでは、高圧側冷媒の圧力もしくは温度を両減圧手段１３ａ、２３の制御因子として過渡状態の時間を短縮し、速やかに効率のよい運転状態へ移行することができる。 According to this, when the pressure or temperature of the high-pressure side refrigerant is changed according to a change in the environmental conditions of at least one of the radiator 12, the first evaporator 14, and the second evaporator 24, the high-pressure side refrigerant Until the pressure reaches a predetermined value, the pressure or temperature of the high-pressure side refrigerant is used as a control factor for the decompression means 13a, 23, so that the time for the transient state can be shortened and the operation state can be quickly shifted to an efficient operation state.

また、制御装置１００は、圧力センサ９２が検出した高圧側冷媒圧力に基づいて、ノズル部１３ａの減圧量を制御している。このように、高圧側冷媒圧力を制御因子とすることで、圧縮機１１に吸入される冷媒の状態に関わらず放熱器１２による放熱の効率が最適となる冷媒状態まで圧力を高めることが可能である。 Further, the control device 100 controls the pressure reduction amount of the nozzle portion 13a based on the high-pressure side refrigerant pressure detected by the pressure sensor 92. In this way, by using the high-pressure side refrigerant pressure as a control factor, it is possible to increase the pressure to a refrigerant state where the efficiency of heat dissipation by the radiator 12 is optimum regardless of the state of the refrigerant sucked into the compressor 11. is there.

また、制御装置１００は、第１蒸発器冷媒温度センサ９３が検出した冷媒温度と第２蒸発器冷媒温度センサ９４が検出した冷媒温度と差に基づいて、膨張弁２３の減圧量を制御している。これによると、比較的安価な手段により冷媒温度差を検出することができる。 Further, the control device 100 controls the pressure reduction amount of the expansion valve 23 based on the difference between the refrigerant temperature detected by the first evaporator refrigerant temperature sensor 93 and the refrigerant temperature detected by the second evaporator refrigerant temperature sensor 94. Yes. According to this, the refrigerant temperature difference can be detected by a relatively inexpensive means.

（第２の実施形態）
次に、第２の実施形態について図４に基づいて説明する。 (Second Embodiment)
Next, a second embodiment will be described with reference to FIG.

本第２の実施形態は、前述の第１の実施形態と比較して、両減圧手段を膨張弁とし、分岐通路の下流側接続点を第１蒸発器の下流側とした点が異なる。なお、第１の実施形態と同様の部分については、同一の符号をつけ、その説明を省略する。 The second embodiment differs from the first embodiment described above in that both decompression means are expansion valves and the downstream connection point of the branch passage is downstream of the first evaporator. In addition, about the part similar to 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

図４に示すように、本実施形態では、冷媒分岐通路（分岐通路に相当）２０Ａの下流端が冷媒循環通路１０の第１蒸発器１４の下流側かつ圧縮機１１の上流側に接続している。また、冷媒循環回路１０に設けた第１減圧手段を膨張弁１１３としている。膨張弁１１３も電子膨張弁であり、開度調節を行うことで冷媒減圧量を調節できるようになっている。 As shown in FIG. 4, in this embodiment, the downstream end of the refrigerant branch passage (corresponding to the branch passage) 20 </ b> A is connected to the downstream side of the first evaporator 14 and the upstream side of the compressor 11 in the refrigerant circulation passage 10. Yes. Further, the first pressure reducing means provided in the refrigerant circulation circuit 10 is an expansion valve 113. The expansion valve 113 is also an electronic expansion valve, and the refrigerant decompression amount can be adjusted by adjusting the opening degree.

そして、図４では図示を省略した制御装置は、第１の実施形態と同様に、運転を開始してから高圧側圧力が所定圧に到達するまでは、膨張弁１１３の減圧量および膨張弁２３の減圧量をともに高圧側圧力に基づいて制御し、運転を開始し高圧側圧力が所定圧に到達した後は、膨張弁１１３の減圧量を高圧側圧力に基づいて制御し、膨張弁２３の減圧量を第１蒸発器１４内の冷媒と第２蒸発器２４内の冷媒との温度差に基づいて制御している。 Then, in the same manner as in the first embodiment, the control device not shown in FIG. 4 starts the operation until the high-pressure side pressure reaches the predetermined pressure until the pressure reduction amount of the expansion valve 113 and the expansion valve 23. After the operation is started and the high pressure side pressure reaches the predetermined pressure, the pressure reduction amount of the expansion valve 113 is controlled based on the high pressure side pressure. The amount of pressure reduction is controlled based on the temperature difference between the refrigerant in the first evaporator 14 and the refrigerant in the second evaporator 24.

したがって、高圧側冷媒圧力が所定値に到達するまでは、高圧側冷媒の圧力を両減圧手段１１３、２３の制御因子として高圧側圧力の上昇速度を高め、速やかに効率のよい運転状態へ移行することができる。また、高圧側圧力が所定圧に到達した後は、圧縮機１１から吐出され膨張弁１１３および膨張弁２３で減圧される前の冷媒の圧力や温度等の状態、すなわち高圧側の冷媒状態（例えば圧縮機１１出口冷媒温度、放熱器１２下流側圧力）を、放熱器１２における放熱の効率が最適となる冷媒状態とすることができる。さらに、第１蒸発器１４内の冷媒と第２蒸発器２４内の冷媒との温度差を、空気流れ方向ＡＡに並設された第１蒸発器１４、第２蒸発器２４において着霜を抑制して外部流体から吸熱する効率が良好な温度差とすることができる。 Therefore, until the high-pressure side refrigerant pressure reaches a predetermined value, the pressure of the high-pressure side refrigerant is used as a control factor for both the decompression means 113 and 23 to increase the rising speed of the high-pressure side pressure, and the operation state is quickly shifted to an efficient operation state. be able to. In addition, after the high-pressure side pressure reaches a predetermined pressure, the refrigerant pressure and temperature before being discharged from the compressor 11 and depressurized by the expansion valve 113 and the expansion valve 23, that is, the high-pressure side refrigerant state (for example, The refrigerant temperature at the outlet of the compressor 11 and the pressure on the downstream side of the radiator 12) can be set to a refrigerant state in which the efficiency of heat radiation in the radiator 12 is optimal. Further, the temperature difference between the refrigerant in the first evaporator 14 and the refrigerant in the second evaporator 24 is used to suppress frost formation in the first evaporator 14 and the second evaporator 24 arranged in parallel in the air flow direction AA. Thus, the efficiency of absorbing heat from the external fluid can be made a good temperature difference.

図４に示すような構成の冷凍サイクルは、各減圧手段の下流側に独立した蒸発器を設定しており、各減圧手段の開口面積を調整することで、それぞれの蒸発器の蒸発温度を自在に設定することができる。これにより、例えば、風上側の蒸発温度を高くし、風下側の蒸発温度を低くすれば着霜を各蒸発器に均等に分布させ、除霜回数の頻度を減少させることができるなどの利点がある。 In the refrigeration cycle configured as shown in FIG. 4, an independent evaporator is set downstream of each decompression means, and the evaporation temperature of each evaporator can be freely adjusted by adjusting the opening area of each decompression means. Can be set to Thereby, for example, if the evaporating temperature on the windward side is increased and the evaporating temperature on the leeward side is decreased, frosting can be evenly distributed to each evaporator, and the frequency of defrosting can be reduced. is there.

本実施形態では、２つの可変式の膨張弁１１３、２３のうち一方の制御因子を、圧縮機１１から膨張弁１１３、２３の間の冷媒状態とし、他方の制御因子を蒸発温度差としているので、放熱器１２の放熱性能が最も効率のよいように高圧側の冷媒状態を調整でき、かつ蒸発器の蒸発温度水準を望ましい状態に調整することができる。例えば着霜する条件の時は風上側の蒸発温度を高くし、風下側の蒸発温度を低くすることができる。 In the present embodiment, one control factor of the two variable expansion valves 113 and 23 is the refrigerant state between the compressor 11 and the expansion valves 113 and 23, and the other control factor is the evaporation temperature difference. The refrigerant state on the high pressure side can be adjusted so that the heat dissipation performance of the radiator 12 is most efficient, and the evaporation temperature level of the evaporator can be adjusted to a desired state. For example, the evaporating temperature on the windward side can be increased and the evaporating temperature on the leeward side can be lowered during the frosting condition.

なお、本実施形態の冷凍サイクルでは、第１蒸発器１４内の冷媒と第２蒸発器２４内の冷媒とに温度差を設ける、換言すれば圧力差を設けるので、冷媒循環回路１０の第１蒸発器１４より下流側かつ冷媒分岐通路２０Ａ下流端接続部より上流側となる部位に、オリフィス等の絞り手段を設けている。 In the refrigeration cycle of the present embodiment, a temperature difference is provided between the refrigerant in the first evaporator 14 and the refrigerant in the second evaporator 24, in other words, a pressure difference is provided. A throttle means such as an orifice is provided at a site downstream of the evaporator 14 and upstream of the downstream end connection portion of the refrigerant branch passage 20A.

（他の実施形態）
上記各実施形態では、高圧側冷媒圧力が所定圧に到達した後は、ノズル部１３ａもしくは膨張弁１１３を高圧側冷媒圧力に基づいて制御し、膨張弁２３を第１蒸発器１４、第２蒸発器２４の冷媒蒸発温度差に基づいて制御していたが、制御因子は逆であってもかまわない。 (Other embodiments)
In each of the above embodiments, after the high-pressure side refrigerant pressure reaches a predetermined pressure, the nozzle portion 13a or the expansion valve 113 is controlled based on the high-pressure side refrigerant pressure, and the expansion valve 23 is controlled by the first evaporator 14 and the second evaporation. Although the control is based on the refrigerant evaporation temperature difference of the vessel 24, the control factor may be reversed.

また、上記各実施形態では、ノズル部１３ａもしくは膨張弁１１３の制御因子を高圧側冷媒圧力としていたが、高圧側の冷媒温度であってもかまわない。例えば、圧縮機１１から吐出される冷媒の温度を検出する吐出冷媒温度検出手段としての吐出温度センサ９１が検出する冷媒温度に基づいて、ノズル部１３ａもしくは膨張弁１１３の減圧量を制御するものであってもよい。 Moreover, in each said embodiment, although the control factor of the nozzle part 13a or the expansion valve 113 was made into the high pressure side refrigerant | coolant pressure, it may be the refrigerant | coolant temperature of a high voltage | pressure side. For example, the pressure reduction amount of the nozzle portion 13a or the expansion valve 113 is controlled based on the refrigerant temperature detected by the discharge temperature sensor 91 serving as a discharge refrigerant temperature detecting means for detecting the temperature of the refrigerant discharged from the compressor 11. There may be.

これによると、圧縮機１１の出口冷媒温度を制御因子とすることで、圧縮機１１の耐熱温度を超えることなく運転させることが可能であり、圧縮機１１の寿命低下を抑止することができる。 According to this, by setting the outlet refrigerant temperature of the compressor 11 as a control factor, the compressor 11 can be operated without exceeding the heat-resistant temperature of the compressor 11, and the life reduction of the compressor 11 can be suppressed.

また、上記各実施形態では、高圧側冷媒圧力が所定値に到達するまで、高圧側冷媒の圧力を両減圧手段の制御因子として高圧側圧力を速やかに変化させていたが、高圧側の冷媒温度が所定値に到達するまで、高圧側冷媒の圧力もしくは温度を両減圧手段の制御因子として高圧側圧力を速やかに変化させるものであってもよい。また、制御の切り換えの判断は、直接高圧側冷媒の圧力もしくは温度によるものでなくてもよく、高圧側の圧力変化もしくは温度変化の度合いを加味して決定した所定時間を基準として行うものであってもよい。 In each of the above embodiments, the high-pressure side pressure is rapidly changed using the pressure of the high-pressure side refrigerant as a control factor for both decompression means until the high-pressure side refrigerant pressure reaches a predetermined value. Until the pressure reaches a predetermined value, the pressure or temperature of the high-pressure side refrigerant may be used as a control factor for both decompression means to quickly change the high-pressure side pressure. In addition, the determination of control switching does not have to be directly based on the pressure or temperature of the high-pressure side refrigerant, and is performed based on a predetermined time determined in consideration of the degree of pressure change or temperature change on the high-pressure side. May be.

また、上記各実施形態では、第１蒸発器１４内の冷媒温度および第２蒸発器２４内の冷媒温度をそれぞれの蒸発器１４、２４の入口側に設けた温度センサ９３、９４で検出していたが、温度センサは各蒸発器１４、２４の冷媒流通経路の途中や各蒸発器１４、２４の出口側に設けるものであってもよい。また、温度センサは配管等の冷媒通路形成部材の表面に配設されるものであってもよいが、冷媒通路形成部材の内部に配設され冷媒通路内の冷媒温度を直接検出するものであってもよい。 Further, in each of the above embodiments, the refrigerant temperature in the first evaporator 14 and the refrigerant temperature in the second evaporator 24 are detected by the temperature sensors 93 and 94 provided on the inlet side of the respective evaporators 14 and 24. However, the temperature sensor may be provided in the middle of the refrigerant flow path of each evaporator 14, 24 or on the outlet side of each evaporator 14, 24. The temperature sensor may be provided on the surface of the refrigerant passage forming member such as a pipe, but is provided inside the refrigerant passage forming member and directly detects the refrigerant temperature in the refrigerant passage. May be.

また、上記各実施形態では、膨張弁２３は、両蒸発器１４、２４内の冷媒温度差に基づいて制御していたが、両蒸発器１４、２４内の冷媒の圧力差もしくは圧力差に関連する物理量に基づいて制御するものであればよい。両蒸発器１４、２４内の冷媒温度差は両蒸発器１４、２４内の圧力差に関連する物理量である。 In each of the above embodiments, the expansion valve 23 is controlled based on the refrigerant temperature difference between the evaporators 14 and 24. However, the expansion valve 23 is related to the refrigerant pressure difference or the pressure difference between the evaporators 14 and 24. What is necessary is just to control based on the physical quantity to be performed. The refrigerant temperature difference between the evaporators 14 and 24 is a physical quantity related to the pressure difference between the evaporators 14 and 24.

したがって、例えば、第１蒸発器１４内を流れる冷媒の圧力を検出するための第１蒸発器冷媒圧力検出手段と、第２蒸発器２４内を流れる冷媒の圧力を検出するための第２蒸発器冷媒圧力検出手段とを備え、第１蒸発器冷媒圧力検出手段が検出した冷媒圧力と第２蒸発器冷媒圧力手段が検出した冷媒圧力と差に基づいて、膨張弁２３の減圧量を制御するものであってもよい。これによれば、第１蒸発器１４内の冷媒圧力と第２蒸発器２４内の冷媒圧力とを直接検知して、正確な冷媒の圧力差に基づいて、膨張弁２３の減圧量を制御することができる。 Therefore, for example, the first evaporator refrigerant pressure detecting means for detecting the pressure of the refrigerant flowing in the first evaporator 14 and the second evaporator for detecting the pressure of the refrigerant flowing in the second evaporator 24. A refrigerant pressure detecting means for controlling the pressure reduction amount of the expansion valve 23 based on the difference between the refrigerant pressure detected by the first evaporator refrigerant pressure detecting means and the refrigerant pressure detected by the second evaporator refrigerant pressure means. It may be. According to this, the refrigerant pressure in the first evaporator 14 and the refrigerant pressure in the second evaporator 24 are directly detected, and the pressure reduction amount of the expansion valve 23 is controlled based on the accurate refrigerant pressure difference. be able to.

また、上記各実施形態では、分岐点で分岐した２つの冷媒通路にそれぞれ減圧手段を設けていた（各冷媒通路に１つずつ２つの減圧手段を設けていた）が、３つ以上に分岐した各冷媒通路のそれぞれ減圧手段を設け、３つ以上の減圧手段の少なくとも２つについて本発明を適用するものであってもよい。 Further, in each of the above embodiments, the pressure reducing means is provided in each of the two refrigerant passages branched at the branch point (two pressure reducing means are provided in each refrigerant passage one by one). Each refrigerant passage may be provided with a decompression unit, and the present invention may be applied to at least two of the three or more decompression units.

また、上記各実施形態では、給湯装置用の冷凍サイクルについて説明したが、給湯装置用に限らず、他の用途の冷凍サイクルであっても本発明を同様に適用できることはもちろんである。例えば、定置用もしくは車両用の空調装置に用いる冷凍サイクルであってもよい。 Moreover, although each said embodiment demonstrated the refrigerating cycle for hot-water supply apparatuses, it is needless to say that this invention can be similarly applied not only to a hot-water supply apparatus but also to other refrigerating cycles. For example, it may be a refrigeration cycle used in a stationary or vehicle air conditioner.

また、上記各実施形態では、冷媒の種類を特定しなかったが、冷媒はフロン系、ＨＣ系の代替フロン、二酸化炭素（ＣＯ₂）など蒸気圧縮式の超臨界サイクルおよび亜臨界サイクルのいずれに適用できるものであってもよい。 In each of the above embodiments, the type of the refrigerant was not specified, but the refrigerant may be any one of a supercritical cycle and a subcritical cycle of a vapor compression type such as CFC-based, HC-based alternative CFC, carbon dioxide (CO ₂ ). It may be applicable.

なお、ここでフロンとは炭素、フッ素、塩素、水素からなる有機化合物の総称であり、冷媒として広く使用されているものである。フロン系冷媒には、ＨＣＦＣ（ハイドロ・クロロ・フルオロ・カーボン）系冷媒、ＨＦＣ（ハイドロ・フルオロ・カーボン）系冷媒等が含まれており、これらはオゾン層を破壊しないため代替フロンと呼ばれる冷媒である。 Here, chlorofluorocarbon is a general term for organic compounds composed of carbon, fluorine, chlorine, and hydrogen, and is widely used as a refrigerant. Fluorocarbon refrigerants include HCFC (hydro-chloro-fluoro-carbon) refrigerants, HFC (hydro-fluoro-carbon) refrigerants, etc. These are refrigerants called substitute chlorofluorocarbons because they do not destroy the ozone layer. is there.

また、ＨＣ（炭化水素）系冷媒とは、水素、炭素を含み、自然界に存在する冷媒物質のことである。このＨＣ系冷媒には、Ｒ６００ａ（イソブタン）、Ｒ２９０（プロパン）などがある。 The HC (hydrocarbon) refrigerant is a refrigerant substance that contains hydrogen and carbon and exists in nature. Examples of the HC refrigerant include R600a (isobutane) and R290 (propane).

本発明を適用した第１の実施形態における蒸気圧縮式の冷凍サイクル１を示す模式構成図である。1 is a schematic configuration diagram illustrating a vapor compression refrigeration cycle 1 in a first embodiment to which the present invention is applied. 第１の実施形態における制御装置１００の概略制御動作を示すフローチャートである。It is a flowchart which shows schematic control operation | movement of the control apparatus 100 in 1st Embodiment. 外気温度と蒸発温度差の目標値との関係の一例を示すグラフである。It is a graph which shows an example of the relationship between outside temperature and the target value of evaporation temperature difference. 本発明を適用した第２の実施形態における蒸気圧縮式の冷凍サイクル１を示す模式構成図である。It is a schematic block diagram which shows the vapor | steam compression-type refrigerating cycle 1 in 2nd Embodiment to which this invention is applied.

Explanation of symbols

１冷凍サイクル
１０冷媒循環通路（環状通路）
１１圧縮機
１２放熱器
１３エジェクタ
１３ａノズル部（第１減圧手段）
１３ｂ冷媒吸引口
１３ｃ混合部（昇圧部の一部）
１３ｄディフューザ部（昇圧部の一部）
１４第１蒸発器
２０、２０Ａ冷媒分岐通路（分岐通路）
２３膨張弁（第２減圧手段）
２４第２蒸発器
１００制御装置（制御手段）
１１３膨張弁（第１減圧手段） 1 Refrigeration cycle 10 Refrigerant circulation passage (annular passage)
DESCRIPTION OF SYMBOLS 11 Compressor 12 Radiator 13 Ejector 13a Nozzle part (1st pressure reduction means)
13b Refrigerant suction port 13c Mixing part (part of the pressure raising part)
13d Diffuser section (part of booster section)
14 1st evaporator 20, 20A Refrigerant branch passage (branch passage)
23 Expansion valve (second decompression means)
24 Second evaporator 100 Control device (control means)
113 Expansion valve (first decompression means)

Claims

A compressor (11) for sucking and compressing and discharging the refrigerant;
A radiator (12) for radiating the refrigerant discharged from the compressor (11);
A first depressurizing means (13a) of variable depressurization amount for depressurizing and expanding the refrigerant flowing out of the radiator (12);
A first evaporator (14) for evaporating the refrigerant decompressed by the first decompression means (13a);
The compressor (11), the radiator (12), the first decompression means (13a), the first so that the refrigerant evaporated in the first evaporator (14) is sucked into the compressor (11). An annular passage (10) in which one evaporator (14) is annularly connected;
A part of the refrigerant that is provided so as to branch from between the radiator (12) of the annular passage (10) and the first pressure reducing means (13a) and flows out of the radiator (12) A branch passage (20) that bypasses the first decompression means (13a) and guides the refrigerant to join the refrigerant from the first decompression means (13a) toward the compressor (11);
A second depressurizing means (23) of variable depressurization amount provided in the branch passage (20) and depressurizing and expanding the refrigerant flowing out of the radiator (12);
A second evaporator (24) provided in the branch passage (20) and evaporating the refrigerant decompressed by the second decompression means (23);
Control means (100) for controlling the pressure reduction amount of the first pressure reducing means (13a) and the second pressure reducing means (23),
The first evaporator (14) and the second evaporator (24) are arranged so that the external fluid after passing through the first evaporator (14) passes through the second evaporator (24). A refrigeration cycle,
The control means (100)
One of the first pressure reducing means (13a) and the second pressure reducing means (23) is discharged from the compressor (11) and reduced in pressure by the first and second pressure reducing means (13a, 23). Control based on the pressure or temperature of the refrigerant before
Of the first decompression means (13a) and the second decompression means (23), the other decompression amount is set between the refrigerant in the first evaporator (14) and the refrigerant in the second evaporator (24). Control based on a pressure difference or a physical quantity related to the pressure difference ,
The control means (100)
Of the first depressurizing means (13a) and the second depressurizing means (23), the other depressurization amount is determined by the refrigerant in the first evaporator (14) and the refrigerant in the second evaporator (24). The pressure difference of or the physical quantity related to the pressure difference is controlled to match the target value,
The temperature of the external fluid flowing into the radiator (12), the temperature of the external fluid flowing out of the radiator (12), the temperature of the external fluid flowing into the first evaporator (14), and the first evaporation The target value is changed according to at least one of the humidity of the external fluid which flows into a container (14), The refrigerating cycle characterized by the above-mentioned .

A compressor (11) for sucking and compressing and discharging the refrigerant;
A radiator (12) for radiating the refrigerant discharged from the compressor (11);
A first depressurizing means (13a) of variable depressurization amount for depressurizing and expanding the refrigerant flowing out of the radiator (12);
A first evaporator (14) for evaporating the refrigerant decompressed by the first decompression means (13a);
The compressor (11), the radiator (12), the first decompression means (13a), the first so that the refrigerant evaporated in the first evaporator (14) is sucked into the compressor (11). An annular passage (10) in which one evaporator (14) is annularly connected;
A part of the refrigerant that is provided so as to branch from between the radiator (12) of the annular passage (10) and the first pressure reducing means (13a) and flows out of the radiator (12) A branch passage (20) that bypasses the first decompression means (13a) and guides the refrigerant to join the refrigerant from the first decompression means (13a) toward the compressor (11);
A second depressurizing means (23) of variable depressurization amount provided in the branch passage (20) and depressurizing and expanding the refrigerant flowing out of the radiator (12);
A second evaporator (24) provided in the branch passage (20) and evaporating the refrigerant decompressed by the second decompression means (23);
Control means (100) for controlling the pressure reduction amount of the first pressure reducing means (13a) and the second pressure reducing means (23),
The first evaporator (14) and the second evaporator (24) are arranged so that the external fluid after passing through the first evaporator (14) passes through the second evaporator (24). A refrigeration cycle,
The control means (100)
One of the first pressure reducing means (13a) and the second pressure reducing means (23) is discharged from the compressor (11) and reduced in pressure by the first and second pressure reducing means (13a, 23). Control based on the pressure or temperature of the refrigerant before
Of the first decompression means (13a) and the second decompression means (23), the other decompression amount is set between the refrigerant in the first evaporator (14) and the refrigerant in the second evaporator (24). Control based on a pressure difference or a physical quantity related to the pressure difference ,
The control means (100)
Of the first depressurizing means (13a) and the second depressurizing means (23), the other depressurization amount is determined by the refrigerant in the first evaporator (14) and the refrigerant in the second evaporator (24). The pressure difference of or the physical quantity related to the pressure difference is controlled to match the target value,
The refrigeration cycle , wherein the target value is changed according to an outer surface temperature of at least one of the first evaporator (14) and the second evaporator (24) .

The nozzle part (13a) that converts the pressure energy of the refrigerant flowing out of the radiator (12) into velocity energy to decompress and expand the refrigerant, and the refrigerant is sucked into the interior by the refrigerant flow injected from the nozzle part (13a). While mixing the refrigerant sucked from the refrigerant suction port (13b) and the nozzle part (13a) and the refrigerant sucked from the refrigerant suction port (13b), the speed energy is converted into pressure energy to increase the pressure of the refrigerant. An ejector (13) having a booster (13c, 13d);
The first pressure reducing means (13a) is the nozzle portion (13a),
The branch passage (20) has a downstream end connected to the refrigerant suction port (13b), and allows the refrigerant evaporated in the second evaporator (24) to flow into the refrigerant suction port (13b). The refrigeration cycle according to claim 1 or 2 .

Pressure detection means (92) for detecting the pressure of the refrigerant discharged from the compressor (11) and decompressed by the first and second pressure reduction means (13a, 23);
The control means (100) controls the pressure reduction amount of one of the first pressure reduction means (13a) and the second pressure reduction means (23) based on the pressure detected by the pressure detection means (92). The refrigeration cycle according to any one of claims 1 to 3, wherein:

A discharge refrigerant temperature detection means (91) for detecting the temperature of the refrigerant discharged from the compressor (11),
Based on the refrigerant temperature detected by the discharged refrigerant temperature detecting means (91), the control means (100) is configured to reduce one of the first pressure reducing means (13a) and the second pressure reducing means (23). The refrigeration cycle according to any one of claims 1 to 3, wherein the refrigeration cycle is controlled.

First evaporator refrigerant pressure detecting means for detecting the pressure of the refrigerant flowing in the first evaporator (14);
A second evaporator refrigerant pressure detecting means for detecting the pressure of the refrigerant flowing in the second evaporator (24),
Based on the difference between the refrigerant pressure detected by the first evaporator refrigerant pressure detecting means and the refrigerant pressure detected by the second evaporator refrigerant pressure means, the control means (100) is configured to output the first pressure reducing means (13a). The refrigeration cycle according to any one of claims 1 to 5, wherein the pressure reduction amount of the other of the second pressure reduction means (23) is controlled.

First evaporator refrigerant temperature detecting means (93) for detecting the temperature of the refrigerant flowing in the first evaporator (14);
Second evaporator refrigerant temperature detecting means (94) for detecting the temperature of the refrigerant flowing in the second evaporator (24),
The control means (100) determines the difference between the refrigerant temperature detected by the first evaporator refrigerant temperature detection means (93) and the refrigerant temperature detected by the second evaporator refrigerant temperature detection means (94) as the pressure difference. 6. The control unit according to any one of claims 1 to 5, wherein the other decompression amount of the first decompression unit (13a) and the second decompression unit (23) is controlled. The refrigeration cycle described in 1.

The control means (100)
Immediately after starting the operation of the compressor (11), the reduced pressure amount of the first pressure reducing means (13a) and the reduced pressure amount of the second pressure reducing means (23) are discharged from the compressor (11) and the first pressure reducing means (23) is discharged. 1. Control based on the pressure or temperature of the refrigerant before being decompressed by the second decompression means (13a, 23),
After the refrigerant pressure or temperature discharged from the compressor (11) and before being depressurized by the first and second decompression means (13a, 23) reaches a predetermined value, the first decompression means (13a) And the pressure reduction of one of the second decompression means (23) is the pressure of the refrigerant before being discharged from the compressor (11) and decompressed by the first and second decompression means (13a, 23) or The other decompression amount of the first decompression means (13a) and the second decompression means (23) is controlled based on the temperature, and the refrigerant in the first evaporator (14) and the second evaporator The refrigeration cycle according to any one of claims 1 to 7, wherein the refrigeration cycle is controlled based on a pressure difference with the refrigerant in (24) or a physical quantity related to the pressure difference.

The control means (100)
The temperature of the external fluid flowing into the radiator (12), the temperature of the external fluid flowing out of the radiator (12), the temperature of the external fluid flowing into the first evaporator (14), and the first evaporation Refrigerant before being discharged from the compressor (11) and decompressed by the first and second decompression means (13a, 23) according to a change in at least one of the humidity of the external fluid flowing into the container (14) When changing the pressure or temperature of
Before the pressure or temperature of the refrigerant discharged from the compressor (11) and decompressed by the first and second decompression means (13a, 23) reaches a predetermined value, the first decompression means (13a) And the pressure or temperature of the refrigerant before being decompressed by the first and second decompression means (13a, 23), from the compressor (11). Control based on
After the pressure or temperature of the refrigerant discharged from the compressor (11) and decompressed by the first and second decompression means (13a, 23) reaches the predetermined value, the first decompression means (13a ) And the second decompression means (23), the pressure of the refrigerant before the one decompression amount is discharged from the compressor (11) and decompressed by the first and second decompression means (13a, 23). Alternatively, the other decompression amount of the first decompression means (13a) and the second decompression means (23) is controlled based on the temperature, and the refrigerant in the first evaporator (14) and the second evaporation are controlled. The refrigeration cycle according to any one of claims 1 to 7, wherein the refrigeration cycle is controlled based on a pressure difference with the refrigerant in the vessel (24) or a physical quantity related to the pressure difference.