JP2011196594A

JP2011196594A - Refrigeration cycle device

Info

Publication number: JP2011196594A
Application number: JP2010062361A
Authority: JP
Inventors: Michimi Kusaka; 道美日下
Original assignee: Panasonic Corp
Current assignee: Panasonic Corp
Priority date: 2010-03-18
Filing date: 2010-03-18
Publication date: 2011-10-06
Anticipated expiration: 2030-03-18
Also published as: JP5333305B2

Abstract

PROBLEM TO BE SOLVED: To detect generation of surplus oil only by simple temperature detection, preventing flowing-out of oil from an oil separator, and ensuring reliability of a compressor.SOLUTION: The compressor 11, the oil separator 12, a condenser 13, a pressure reducing means 14 and an evaporator 15 are annularly connected, these refrigeration cycle components are connected by refrigerant piping 16, further the oil separator 12 has a first opening/closing valve 19, an oil storage container 20, a second opening/closing valve 21 and a second capillary tube 22 in parallel with a first capillary tube 17, and an outlet of the second capillary tube 22 is joined to a connection pipe 18. The refrigerant piping 16 is provided with a first temperature sensor 23, and a second temperature sensor 23 is disposed on a connection pipe 18 between an outlet of the first capillary tube 17 and a joining section of the second capillary tube 22. Further, a first opening/closing valve control means 25 is disposed to control opening/closing of the first opening/closing valve 19 and the second opening/closing valve 21 according to the temperatures detected by the first temperature sensor 23 and the second temperature sensor 24.

Description

本発明は、冷凍サイクルにおける余剰オイル量調整方法に関するものである。 The present invention relates to a surplus oil amount adjusting method in a refrigeration cycle.

従来、余剰オイルの貯留量調整方法は、図５に示すように、油溜め容器７が開閉弁８を介して油分離器２とオイル戻しキャピラリチューブ９の間に直列に配置され、予め入力した冷媒配管長から余剰オイル量を算出し、算出された余剰オイル量となるように予め設定された時間間隔で開閉弁８の開閉を制御し、圧縮機１の吸入配管に所定のオイルを返油して冷凍サイクル中を循環する総オイル量を制御するものである（例えば、特許文献１参照）。 Conventionally, as shown in FIG. 5, the method for adjusting the amount of excess oil stored is such that an oil sump container 7 is arranged in series between an oil separator 2 and an oil return capillary tube 9 via an on-off valve 8 and input in advance. The surplus oil amount is calculated from the length of the refrigerant pipe, and the opening / closing of the on-off valve 8 is controlled at a preset time interval so that the calculated surplus oil amount is obtained, and predetermined oil is returned to the suction pipe of the compressor 1. Thus, the total amount of oil circulating in the refrigeration cycle is controlled (see, for example, Patent Document 1).

特許第４２７４２３５号公報Japanese Patent No. 4274235

しかしながら、この方法では、配管長の計測誤差による余剰オイル量の算出誤差や運転状態の変化や配管の設置形状の違いによるオイル滞留量の変化により、正確なオイル滞留量の把握ができず、余剰オイルの回収不足等による性能低下や過剰回収による信頼性の低下が課題として挙げられる。更に、通常のオイル戻しラインに直列に油溜め容器と開閉弁を配置しているため、開閉弁８が故障した場合、通常の油分離器からのオイル戻しもなくなるため、圧縮機１の油量低下となり圧縮機の信頼性の低下が挙げられる。 However, with this method, it is not possible to accurately grasp the oil retention amount due to the calculation error of the surplus oil amount due to the measurement error of the pipe length, the change of the oil retention amount due to the change in the operating state or the difference in the installation shape of the piping, and the surplus oil retention amount cannot be grasped. Problems include performance degradation due to insufficient oil recovery, etc. and reliability degradation due to excessive recovery. Furthermore, since the oil sump container and the on-off valve are arranged in series with the normal oil return line, if the on-off valve 8 breaks down, there is no oil return from the normal oil separator. And the reliability of the compressor is reduced.

上記課題を解決するために本発明は、簡単な温度検知のみで余剰オイルの発生を検知し、油分離器からの流出を防止するとともに、圧縮機の信頼性を確保できる冷凍サイクル装置を提供することを目的とする。 In order to solve the above problems, the present invention provides a refrigeration cycle apparatus capable of detecting the generation of excess oil only by simple temperature detection, preventing outflow from an oil separator, and ensuring the reliability of the compressor. For the purpose.

前記従来の課題を解決するために、本発明の冷凍サイクル装置は、圧縮機の吐出側を、油分離器、第１の流路抵抗体を介して前記圧縮機の吸入側に接続する接続管と、前記油分離器に連通し前記第１の流路抵抗体に並列に、第１の流路開閉手段、油溜め容器、第２の流路抵抗体を順次直列に接続する接続管とを備えたものである。 In order to solve the conventional problem, a refrigeration cycle apparatus according to the present invention includes a connecting pipe that connects a discharge side of a compressor to an intake side of the compressor via an oil separator and a first flow path resistor. And a connecting pipe that communicates with the oil separator and is connected in series with the first flow path opening / closing means, the oil sump container, and the second flow path resistance in parallel with the first flow path resistor. It is provided.

これによって、余剰オイルが発生する運転条件では、第１の流路開閉手段を開放することにより、油溜め容器に余剰オイルを溜めながら運転することができ、冷凍サイクル中への余剰オイルの流出を防止することができる。 As a result, under operating conditions in which surplus oil is generated, the first flow path opening / closing means can be opened to operate while accumulating surplus oil in the oil sump container, and the surplus oil can flow out into the refrigeration cycle. Can be prevented.

また、第１の流路開閉手段は、第１の流路抵抗体に並列に設置されているため、第１の流路開閉手段が故障などにより閉塞した場合でも通常の油分離器からのオイル戻りを確保することができる。 In addition, since the first flow path opening / closing means is installed in parallel with the first flow path resistor, even if the first flow path opening / closing means is blocked due to a failure or the like, the oil from the normal oil separator A return can be secured.

また、本発明の冷凍サイクル装置は、圧縮機の吐出側を、油分離器、第１の流路抵抗体を介して前記圧縮機の吸入側に接続する接続管と、前記油分離器に連通し前記第１の流路抵抗体に並列に、油溜め容器、第２の流路開閉手段、第２の流路抵抗体を順次直列に接続する接続管とを備えたものである。 Further, the refrigeration cycle apparatus of the present invention communicates with the oil separator, a connection pipe that connects the discharge side of the compressor to the suction side of the compressor via the first flow path resistor. In parallel with the first flow path resistor, an oil sump container, a second flow path opening / closing means, and a connection pipe for sequentially connecting the second flow path resistor in series are provided.

これによって、余剰オイルが発生する運転条件では、第２の流路開閉手段を開放することにより、油溜め容器に余剰オイルを溜め、また、余剰オイルの回収完了は、第２の流路開閉手段を閉止することで、冷凍サイクル中への余剰オイルの流出を防止しながら運転することができる。また、再起動時も余剰オイルを回収した状態で運転を開始することができる。 Thus, under operating conditions in which surplus oil is generated, the second flow path opening / closing means is opened, so that surplus oil is stored in the oil reservoir, and the recovery of the surplus oil is completed by the second flow path opening / closing means. By closing the, the operation can be performed while preventing the excess oil from flowing out into the refrigeration cycle. In addition, the operation can be started in a state where the surplus oil is recovered even at the time of restart.

また、第２の流路開閉手段は、第１の流路抵抗体に並列に設置されているため、第２の流路開閉手段が故障などにより閉塞した場合でも通常の油分離器からのオイル戻りを確保することができる。 In addition, since the second flow path opening / closing means is installed in parallel with the first flow path resistor, the oil from the normal oil separator even when the second flow path opening / closing means is blocked due to a failure or the like. A return can be secured.

また、本発明の冷凍サイクル装置は、圧縮機の吐出側を、油分離器、第１の流路抵抗体を介して前記圧縮機の吸入側に接続する接続管と、前記油分離器に連通し前記第１の流路抵抗体に並列に、第１の流路開閉手段、油溜め容器、第２の流路開閉手段、第２の流路抵抗体を順次直列に接続する接続管とを備えたものである。 Further, the refrigeration cycle apparatus of the present invention communicates with the oil separator, a connection pipe that connects the discharge side of the compressor to the suction side of the compressor via the first flow path resistor. In parallel with the first flow path resistor, a first flow path opening / closing means, an oil sump container, a second flow path opening / closing means, and a connection pipe for sequentially connecting the second flow path resistance body in series. It is provided.

これによって、余剰オイルが発生する運転条件では、第１の流路開閉手段と第２の流路開閉手段を開放することにより、油溜め容器に余剰オイルを溜め、また、余剰オイルの回収完了は、第１の流路開閉手段と第２の流路開閉手段を閉止することで、余剰オイルを油溜め容器に確実に回収することができ、冷凍サイクル中への余剰オイルの流出を防止しながら運転することができる。 As a result, under operating conditions in which surplus oil is generated, surplus oil is stored in the oil sump container by opening the first flow path opening / closing means and the second flow path opening / closing means, and the recovery of the surplus oil is not completed. By closing the first flow path opening / closing means and the second flow path opening / closing means, the excess oil can be reliably recovered in the oil sump container, while preventing the excess oil from flowing out into the refrigeration cycle. You can drive.

また、再起動時も余剰オイルを回収した状態で運転を開始することができる。また、余剰オイルの回収後は、運転中もしくは運転停止中に油溜め容器への過剰なオイルの溜まり込みや冷媒の溜まり込みを防止することができる。 In addition, the operation can be started in a state where the surplus oil is recovered even at the time of restart. In addition, after collecting the excess oil, it is possible to prevent excessive oil accumulation or refrigerant accumulation in the oil reservoir container during operation or during operation stop.

また、第１の流路開閉手段と第２の流路開閉手段は、第１の流路抵抗体に並列に設置されているため、第１の流路開閉手段または第２の流路開閉手段が故障などにより閉塞した場合でも通常の油分離器からのオイル戻りを確保することができる。 Further, since the first flow path opening / closing means and the second flow path opening / closing means are installed in parallel to the first flow path resistor, the first flow path opening / closing means or the second flow path opening / closing means. Even when the oil is blocked due to a failure or the like, the oil return from the normal oil separator can be secured.

本発明によれば、簡単な温度検知のみで余剰オイルの発生を検知し、油分離器からの流出を防止するとともに、圧縮機の信頼性を確保できる冷凍サイクル装置を提供できる。 According to the present invention, it is possible to provide a refrigeration cycle apparatus that detects the generation of excess oil only by simple temperature detection, prevents outflow from the oil separator, and ensures the reliability of the compressor.

本発明の実施の形態１における冷凍サイクル図Refrigeration cycle diagram in Embodiment 1 of the present invention 本発明の実施の形態１における開閉弁制御のフローチャートFlowchart of on-off valve control in Embodiment 1 of the present invention 本発明の実施の形態２における冷凍サイクル図Refrigeration cycle diagram in Embodiment 2 of the present invention 本発明の実施の形態２における開閉弁制御のフローチャートFlowchart of on-off valve control in Embodiment 2 of the present invention 従来の冷凍サイクル図Conventional refrigeration cycle diagram

第１の発明は、圧縮機の吐出側を、油分離器、第１の流路抵抗体を介して前記圧縮機の吸入側に接続する接続管と、前記油分離器に連通し前記第１の流路抵抗体に並列に、第１の流路開閉手段、油溜め容器、第２の流路抵抗体を順次直列に接続する接続管とを備えることにより、余剰オイルが発生する運転条件では、第１の流路開閉手段を開放することにより、油溜め容器に余剰オイルを溜めながら運転し、冷凍サイクル中への余剰オイルの流出を防止することができ、熱交換器の伝熱性能低下の防止や圧力損失を低減し効率よく運転することができる。 According to a first aspect of the present invention, the discharge side of the compressor is connected to the suction side of the compressor via an oil separator, a first flow path resistor, and the first separator communicates with the oil separator. In an operating condition in which surplus oil is generated by providing a first channel opening / closing means, an oil reservoir, and a connecting pipe that sequentially connects the second channel resistor in series with the channel resistor. By opening the first flow path opening / closing means, it is possible to operate while accumulating excess oil in the oil reservoir, and to prevent the excess oil from flowing out into the refrigeration cycle, and to reduce the heat transfer performance of the heat exchanger Prevention and pressure loss can be reduced and operation can be performed efficiently.

また、第１の流路開閉手段は、第１の流路抵抗体に並列に設置されているため、第１の
流路開閉手段が故障などにより閉塞した場合でも通常の油分離器からのオイル戻りを確保することができ、圧縮機の信頼性を確保することができる。 In addition, since the first flow path opening / closing means is installed in parallel with the first flow path resistor, even if the first flow path opening / closing means is blocked due to a failure or the like, the oil from the normal oil separator The return can be ensured, and the reliability of the compressor can be ensured.

第２の発明は、圧縮機の吐出側を、油分離器、第１の流路抵抗体を介して前記圧縮機の吸入側に接続する接続管と、前記油分離器に連通し前記第１の流路抵抗体に並列に、油溜め容器、第２の流路開閉手段、第２の流路抵抗体を順次直列に接続する接続管とを備えることにより、余剰オイルが発生する運転条件では、第２の流路開閉手段を開放することにより、油溜め容器に余剰オイルを溜め、また、余剰オイルの回収完了は、第２の流路開閉手段を閉止することで、冷凍サイクル中への余剰オイルの流出を防止しながら運転することができる。 According to a second aspect of the present invention, the discharge side of the compressor is connected to the suction side of the compressor via an oil separator, a first flow path resistor, and the first separator communicated with the oil separator. In an operating condition in which surplus oil is generated by providing an oil sump container, a second flow path opening / closing means, and a connecting pipe for sequentially connecting the second flow path resistors in series with the flow path resistor. Then, by opening the second flow path opening / closing means, excess oil is stored in the oil reservoir, and when the recovery of the excess oil is completed, the second flow path opening / closing means is closed to enter the refrigeration cycle. It is possible to operate while preventing excess oil from flowing out.

また、再起動時も余剰オイルを回収した状態で運転を開始することができ、より効率よく熱交換器の伝熱性能低下の防止や圧力損失を低減し効率よく運転することができる。 In addition, the operation can be started in a state where the surplus oil is recovered even at the time of restarting, and the heat transfer performance of the heat exchanger can be prevented from being lowered and the pressure loss can be reduced more efficiently.

また、第２の流路開閉手段は、第１の流路抵抗体に並列に設置されているため、第２の流路開閉手段が故障などにより閉塞した場合でも通常の油分離器からのオイル戻りを確保することができ、圧縮機の信頼性を確保することができる。 In addition, since the second flow path opening / closing means is installed in parallel with the first flow path resistor, the oil from the normal oil separator even when the second flow path opening / closing means is blocked due to a failure or the like. The return can be ensured, and the reliability of the compressor can be ensured.

第３の発明は、圧縮機の吐出側を、油分離器、第１の流路抵抗体を介して前記圧縮機の吸入側に接続する接続管と、前記油分離器に連通し前記第１の流路抵抗体に並列に、第１の流路開閉手段、油溜め容器、第２の流路開閉手段、第２の流路抵抗体を順次直列に接続する接続管とを備えることにより、余剰オイルが発生する運転条件では、第１の流路開閉手段と第２の流路開閉手段を開放することにより、油溜め容器に余剰オイルを溜め、余剰オイルの回収完了は、第１の流路開閉手段と第２の流路開閉手段を閉止することで、余剰オイルを油溜め容器に確実に回収することができ、冷凍サイクル中への余剰オイルの流出を防止しながら運転することができる。 According to a third aspect of the present invention, the discharge side of the compressor is connected to the suction side of the compressor via an oil separator, a first flow path resistor, and the first separator communicates with the oil separator. In parallel with the flow path resistor, the first flow path opening and closing means, the oil sump container, the second flow path opening and closing means, and a connection pipe that sequentially connects the second flow path resistance body, Under the operating conditions in which surplus oil is generated, the first flow path opening / closing means and the second flow path opening / closing means are opened to accumulate surplus oil in the oil sump container. By closing the path opening / closing means and the second flow path opening / closing means, the excess oil can be reliably recovered in the oil reservoir, and the operation can be performed while preventing the excess oil from flowing out into the refrigeration cycle. .

また、再起動時も余剰オイルを回収した状態で運転を開始することができ、更に、余剰オイルの回収後は、運転中もしくは運転停止中に油溜め容器への過剰なオイルの溜まり込みや冷媒の溜まり込みを防止することができ、より効率よく熱交換器の伝熱性能低下の防止や圧力損失を低減し効率よく運転することができる。 In addition, the operation can be started in a state where surplus oil has been recovered even after restarting. Further, after the surplus oil has been recovered, excessive oil accumulation or refrigerant in the oil sump container during operation or operation stop Can be prevented, and the heat transfer performance of the heat exchanger can be prevented more effectively and the pressure loss can be reduced to operate efficiently.

また、第１の流路開閉手段と第２の流路開閉手段は、第１の流路抵抗体に並列に設置されているため、第１の流路開閉手段または第２の流路開閉手段が故障などにより閉塞した場合でも通常の油分離器からのオイル戻りを確保することができ、圧縮機の信頼性を確保することができる。 Further, since the first flow path opening / closing means and the second flow path opening / closing means are installed in parallel to the first flow path resistor, the first flow path opening / closing means or the second flow path opening / closing means. Even when the oil is blocked due to a failure or the like, the oil return from the normal oil separator can be secured, and the reliability of the compressor can be secured.

第４の発明は、特に第１の発明において、圧縮機の吐出管に設けた第１の温度センサーと、第１の流路抵抗体出口側の接続管に設けた第２の温度センサーと、制御手段とを備え、前記第１の温度センサーと前記第２の温度センサーとで検知された温度差が所定値以下の場合には、前記第１の流路開閉手段を開放し、前記所定値より大きい場合には、閉止することにより、運転中の冷凍サイクルにおいて、余剰オイルが発生した場合、第１の流路抵抗体をほぼオイルのみが流通する状態となり、減圧後も温度低下が小さいため第２の温度センサーで検知した第１の流路抵抗体出口温度と第１の温度センサーで検知した吐出温度との温度差は小さくなる。 The fourth invention is the first temperature sensor provided in the discharge pipe of the compressor, the second temperature sensor provided in the connection pipe on the outlet side of the first flow path resistor, in particular in the first invention, Control means, and when the temperature difference detected by the first temperature sensor and the second temperature sensor is less than or equal to a predetermined value, the first flow path opening / closing means is opened, and the predetermined value When larger than this, by closing, when surplus oil is generated in the refrigeration cycle during operation, only the oil flows through the first flow path resistor, and the temperature drop is small even after decompression. The temperature difference between the first flow path resistor outlet temperature detected by the second temperature sensor and the discharge temperature detected by the first temperature sensor becomes small.

このため、余剰オイルの発生を検知することができ、余剰オイルが発生した場合、第１の流路開閉手段を開放することにより、油溜め容器に余剰オイルを溜めながら運転し、冷凍サイクル中への余剰オイルの流出を防止することができる。 For this reason, generation | occurrence | production of surplus oil can be detected, and when surplus oil generate | occur | produces, it operates by storing the surplus oil in an oil reservoir container by opening the first flow path opening / closing means, and enters the refrigeration cycle. It is possible to prevent the excess oil from flowing out.

また、余剰オイルの発生がない場合は、第１の流路開閉手段を閉止することにより、冷凍サイクル中のオイル量を適正化することができるため、熱交換器の伝熱性能低下の防止や圧力損失を低減し効率よく運転することができるとともに、冷凍サイクル中を循環するオイル量を適正化することができるため圧縮機の信頼性を向上することができる。 In addition, when there is no surplus oil generation, the amount of oil in the refrigeration cycle can be optimized by closing the first flow path opening / closing means, so that the heat transfer performance of the heat exchanger can be prevented from being lowered. The pressure loss can be reduced and the operation can be efficiently performed, and the amount of oil circulating in the refrigeration cycle can be optimized, so that the reliability of the compressor can be improved.

第５の発明は、特に第２の発明において、圧縮機の吐出管に設けた第１の温度センサーと、第１の流路抵抗体出口側の接続管に設けた第２の温度センサーと、制御手段とを備え、前記第１の温度センサーと前記第２の温度センサーとで検知された温度差が所定値以下の場合には、前記第２の流路開閉手段を開放し、前記所定値より大きい場合には、閉止することにより、運転中の冷凍サイクルにおいて、余剰オイルが発生した場合、第１の流路抵抗体をほぼオイルのみが流通する状態となり、減圧後も温度低下が小さいため第２の温度センサーで検知した第１の流路抵抗体出口温度と第１の温度センサーで検知した吐出温度との温度差は小さくなる。 The fifth invention is the first temperature sensor provided in the discharge pipe of the compressor, and the second temperature sensor provided in the connection pipe on the outlet side of the first flow path resistor, particularly in the second invention, Control means, and when the temperature difference detected by the first temperature sensor and the second temperature sensor is less than or equal to a predetermined value, the second flow path opening / closing means is opened, and the predetermined value When larger than this, by closing, when surplus oil is generated in the refrigeration cycle during operation, only the oil flows through the first flow path resistor, and the temperature drop is small even after decompression. The temperature difference between the first flow path resistor outlet temperature detected by the second temperature sensor and the discharge temperature detected by the first temperature sensor becomes small.

このため、余剰オイルの発生を検知することができ、余剰オイルの発生を検知した場合、第２の流路開閉手段を開放することにより、油溜め容器に余剰オイルを回収しながら運転し、余剰オイルがなくなったと検知した場合、第２の流路開閉手段を閉止することにより、余剰オイルを油溜め容器に回収した状態で運転することができる。 For this reason, it is possible to detect the generation of surplus oil. When the generation of surplus oil is detected, the second flow path opening / closing means is opened to operate while collecting the surplus oil in the oil sump container. When it is detected that the oil has run out, the second flow path opening / closing means is closed, and the operation can be performed in a state where excess oil is collected in the oil reservoir.

また、再起動時も余剰オイルを回収した状態で運転を開始することができ、より効率よく熱交換器の伝熱性能低下の防止や圧力損失を低減し効率よく運転することができるとともに、冷凍サイクル中を循環するオイル量を適正化することができるため圧縮機の信頼性を向上することができる。 In addition, the operation can be started with the excess oil recovered even at the time of restart, and the heat transfer performance of the heat exchanger can be prevented more effectively and the pressure loss can be reduced and the operation can be efficiently performed. Since the amount of oil circulating in the cycle can be optimized, the reliability of the compressor can be improved.

第６の発明は、第１の発明において、圧縮機の吐出管に設けた第１の温度センサーと、第１の流路抵抗体出口側の接続管に設けた第２の温度センサーと、制御手段とを備え、前記第１の温度センサーと前記第２の温度センサーとで検知された温度差が所定値以下の場合には、前記第１の流路開閉手段と前記第２の流路開閉手段を開放し、前記所定値より大きい場合には、閉止することにより、運転中の冷凍サイクルにおいて、余剰オイルが発生した場合、第１の流路抵抗体をほぼオイルのみが流通する状態となり、減圧後も温度低下が小さいため第２の温度センサーで検知した第１の流路抵抗体出口温度と第１の温度センサーで検知した吐出温度との温度差は小さくなる。 In a sixth aspect based on the first aspect, the first temperature sensor provided in the discharge pipe of the compressor, the second temperature sensor provided in the connection pipe on the outlet side of the first flow path resistor, and control And when the temperature difference detected by the first temperature sensor and the second temperature sensor is equal to or less than a predetermined value, the first channel opening / closing unit and the second channel opening / closing When the means is opened and is larger than the predetermined value, it is closed, and when surplus oil is generated in the refrigeration cycle during operation, only the oil flows through the first flow path resistor, Since the temperature drop is small even after the pressure reduction, the temperature difference between the first flow path resistor outlet temperature detected by the second temperature sensor and the discharge temperature detected by the first temperature sensor becomes small.

このため、余剰オイルの発生を検知することができ、余剰オイルの発生を検知した場合、第１の流路開閉手段と第２の流路開閉手段を開放することにより、油溜め容器に余剰オイルを回収しながら運転し、余剰オイルがなくなったと検知した場合、第１の流路開閉手段と第２の流路開閉手段を閉止することにより、余剰オイルを油溜め容器に回収した状態で運転することができる。 For this reason, generation | occurrence | production of surplus oil can be detected, and when generation | occurrence | production of surplus oil is detected, the surplus oil is stored in the oil reservoir container by opening the first flow path opening / closing means and the second flow path opening / closing means. When the excess oil is detected, the first flow path opening / closing means and the second flow path opening / closing means are closed so that the excess oil is recovered in the oil reservoir. be able to.

また、再起動時も余剰オイルを回収した状態で運転を開始することができる。更に、余剰オイルの回収後は、運転中もしくは運転停止中に油溜め容器への過剰なオイルの溜まり込みや冷媒の溜まり込みを防止することができ、より効率よく熱交換器の伝熱性能低下の防止や圧力損失を低減し効率よく運転することができるとともに、冷凍サイクル中を循環するオイル量を適正化することができるため圧縮機の信頼性を向上することができる。 In addition, the operation can be started in a state where the surplus oil is recovered even at the time of restart. In addition, after collecting the excess oil, it is possible to prevent excessive oil accumulation and refrigerant accumulation in the oil reservoir container during operation or shutdown, and more effectively reduce the heat transfer performance of the heat exchanger. In addition, the reliability of the compressor can be improved because the amount of oil circulating in the refrigeration cycle can be optimized.

第７の発明は、第１の発明において、圧縮機の吸入管に設けた第１の温度センサーと、蒸発器の出口側に設けた第２の温度センサーと、制御手段とを備え、前記第１の温度センサーと前記第２の温度センサーとで検知された温度差が所定値以上の場合には、前記第１の流路開閉手段を開放し、前記所定値より小さい場合には、閉止することにより、運転中の冷凍サイクルにおいて、余剰オイルが発生した場合、第１の流路抵抗体をほぼオイルの
みが流通する状態となり、減圧後も温度低下が小さいため圧縮機の吸入管には高温のオイルが多量に流入することになる。 A seventh invention is the first invention, comprising: a first temperature sensor provided in the suction pipe of the compressor; a second temperature sensor provided on the outlet side of the evaporator; and a control means. When the temperature difference detected by the first temperature sensor and the second temperature sensor is greater than or equal to a predetermined value, the first flow path opening / closing means is opened, and when the temperature difference is smaller than the predetermined value, the first flow sensor is closed. As a result, when excess oil is generated in the refrigeration cycle during operation, only the oil flows through the first flow path resistor, and the temperature drop is small even after the pressure is reduced. A large amount of oil flows in.

このため、第１の温度センサーで検知する圧縮機の吸入温度は上昇し始め、この高温オイルの合流部より上流に設置された第２の温度センサーで検知する配管温度との温度差は大きくなることから余剰オイルの発生を検知することができ、余剰オイルが発生した場合、第１の流路開閉手段を開放することにより、油溜め容器に余剰オイルを溜めながら運転し、冷凍サイクル中への余剰オイルの流出を防止することができる。 For this reason, the suction temperature of the compressor detected by the first temperature sensor starts to rise, and the temperature difference from the piping temperature detected by the second temperature sensor installed upstream from the high temperature oil junction increases. Therefore, the generation of surplus oil can be detected, and when surplus oil is generated, the first flow path opening / closing means is opened to operate while accumulating the surplus oil in the oil sump container, and into the refrigeration cycle. It is possible to prevent excess oil from flowing out.

第８の発明は、第２の発明において、圧縮機の吸入管に設けた第１の温度センサーと、蒸発器の出口側に設けた第２の温度センサーと、制御手段とを備え、前記第１の温度センサーと前記第２の温度センサーとで検知された温度差が所定値以上の場合には、前記第２の流路開閉手段を開放し、前記所定値より小さい場合には、閉止することにより、運転中の冷凍サイクルにおいて、余剰オイルが発生した場合、第１の流路抵抗体をほぼオイルのみが流通する状態となり、減圧後も温度低下が小さいため圧縮機の吸入管には高温のオイルが多量に流入することになる。 An eighth invention is the second invention, comprising a first temperature sensor provided in the suction pipe of the compressor, a second temperature sensor provided on the outlet side of the evaporator, and a control means, When the temperature difference detected by the first temperature sensor and the second temperature sensor is greater than or equal to a predetermined value, the second flow path opening / closing means is opened, and when the temperature difference is smaller than the predetermined value, it is closed. As a result, when excess oil is generated in the refrigeration cycle during operation, only the oil flows through the first flow path resistor, and the temperature drop is small even after the pressure is reduced. A large amount of oil flows in.

このため、第１の温度センサーで検知する圧縮機の吸入温度は上昇し始め、この高温オイルの合流部より上流に設置された第２の温度センサーで検知する配管温度との温度差は大きくなることから余剰オイルの発生を検知することができ、余剰オイルの発生を検知した場合、第２の流路開閉手段を開放することにより、油溜め容器に余剰オイルを回収しながら運転し、余剰オイルがなくなったと検知した場合、第２の流路開閉手段を閉止することにより、余剰オイルを油溜め容器に回収した状態で運転することができる。 For this reason, the suction temperature of the compressor detected by the first temperature sensor starts to rise, and the temperature difference from the piping temperature detected by the second temperature sensor installed upstream from the high temperature oil junction increases. Therefore, it is possible to detect the generation of surplus oil. When the generation of surplus oil is detected, the second flow path opening / closing means is opened to operate while collecting the surplus oil in the oil sump container. When it is detected that the oil has disappeared, the second flow path opening / closing means is closed, so that the operation can be performed in a state where surplus oil is collected in the oil reservoir.

第９の発明は、第１の発明において、圧縮機の吸入管に設けた第１の温度センサーと、蒸発器の出口側に設けた第２の温度センサーと、制御手段とを備え、前記第１の温度センサーと前記第２の温度センサーとで検知された温度差が所定値以上の場合には、前記第１の流路開閉手段と前記第２の流路開閉手段とを開放し、前記所定値より小さい場合には、閉止することにより、運転中の冷凍サイクルにおいて、余剰オイルが発生した場合、第１の流路抵抗体をほぼオイルのみが流通する状態となり、減圧後も温度低下が小さいため圧縮機の吸入管には高温のオイルが多量に流入することになる。 A ninth invention comprises the first temperature sensor provided in the suction pipe of the compressor, the second temperature sensor provided on the outlet side of the evaporator, and control means in the first invention, When the temperature difference detected by the first temperature sensor and the second temperature sensor is greater than or equal to a predetermined value, the first flow path opening / closing means and the second flow path opening / closing means are opened, When the oil is smaller than the predetermined value, by closing, when surplus oil is generated in the refrigeration cycle during operation, only the oil flows through the first flow path resistor, and the temperature decreases even after the pressure is reduced. Since it is small, a large amount of hot oil flows into the suction pipe of the compressor.

このため、第１の温度センサーで検知する圧縮機の吸入温度は上昇し始め、この高温オイルの合流部より上流に設置された第２の温度センサーで検知する配管温度との温度差は大きくなることから余剰オイルの発生を検知することができ、余剰オイルの発生を検知した場合、第１の流路開閉手段と第２の流路開閉手段を開放することにより、油溜め容器に余剰オイルを回収しながら運転し、余剰オイルがなくなったと検知した場合、第１の流路開閉手段と第２の流路開閉手段を閉止することにより、余剰オイルを油溜め容器に回収した状態で運転することができる。 For this reason, the suction temperature of the compressor detected by the first temperature sensor starts to rise, and the temperature difference from the piping temperature detected by the second temperature sensor installed upstream from the high temperature oil junction increases. Therefore, the generation of surplus oil can be detected, and when the generation of surplus oil is detected, the surplus oil is put into the sump container by opening the first channel opening / closing means and the second channel opening / closing means. When operating while collecting and detecting that the excess oil is gone, close the first channel opening and closing means and the second channel opening and closing means to operate with the excess oil recovered in the oil reservoir. Can do.

また、再起動時も余剰オイルを回収した状態で運転を開始することができ、また、余剰オイルの回収後は、運転中もしくは運転停止中に油溜め容器への過剰なオイルの溜まり込みや冷媒の溜まり込みを防止することができ、より効率よく熱交換器の伝熱性能低下の防止や圧力損失を低減し効率よく運転することができるとともに、冷凍サイクル中を循環するオイル量を適正化することができるため圧縮機の信頼性を向上することができる。 In addition, the operation can be started with the surplus oil collected even at the time of restart, and after the surplus oil is collected, excessive oil accumulation or refrigerant in the oil sump container during operation or operation stop It is possible to prevent the accumulation of heat, prevent the heat transfer performance of the heat exchanger from decreasing more efficiently, reduce pressure loss and operate efficiently, and optimize the amount of oil circulating in the refrigeration cycle Therefore, the reliability of the compressor can be improved.

以下、本発明の実施の形態について図面を参照しながら説明する。なお、この実施の形態によって本発明が限定されるものではない。 Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

（実施の形態１）
図１は、本発明の第１の実施の形態における冷凍サイクル図、図２は、開閉弁制御のフローチャートを示す。 (Embodiment 1)
FIG. 1 is a refrigeration cycle diagram according to the first embodiment of the present invention, and FIG. 2 is a flowchart of on-off valve control.

図１において、圧縮機１１と油分離器１２と凝縮器１３と減圧手段１４と蒸発器１５は環状に接続され、冷凍サイクルを形成している。これら、冷凍サイクル部品は、互いに冷媒配管１６によって接続され、圧縮機１１と油分離器１２は冷媒配管１６ａ、油分離器１２と凝縮器１３は冷媒配管１６ｂ、凝縮器１３と蒸発器１５は減圧手段１４を介して冷媒配管１６ｃ、蒸発器１５と圧縮機１１は冷媒配管１６ｄによって接続されている。油分離器１２は第１の毛細管１７（第１の流路抵抗体）を介して接続管１８により冷媒配管１６ｄと接続されている。 In FIG. 1, a compressor 11, an oil separator 12, a condenser 13, a pressure reducing means 14, and an evaporator 15 are connected in an annular shape to form a refrigeration cycle. These refrigeration cycle components are connected to each other by a refrigerant pipe 16, the compressor 11 and the oil separator 12 are refrigerant pipe 16 a, the oil separator 12 and the condenser 13 are refrigerant pipe 16 b, and the condenser 13 and the evaporator 15 are decompressed. The refrigerant pipe 16c, the evaporator 15, and the compressor 11 are connected via the means 14 by the refrigerant pipe 16d. The oil separator 12 is connected to the refrigerant pipe 16d by a connecting pipe 18 through a first capillary tube 17 (first flow path resistor).

さらに、油分離器１２は第１の毛細管１７（第１の流路抵抗体）と並列に第１の開閉弁１９（第１の流路開閉手段）と油溜め容器２０と第２の開閉弁２１（第２の流路開閉手段）と第２の毛細管２２（第２の流路抵抗体）を有し、第２の毛細管２２（第２の流路抵抗体）の出口は、接続管１８に合流する。また、冷媒配管１６ａには、第１の温度センサー２３が設置され、接続管１８上にあり第１の毛細管１７（第１の流路抵抗体）出口と第２の毛細管２２（第２の流路抵抗体）の合流部との間に第２の温度センサー２４が設置されている。 Further, the oil separator 12 includes a first open / close valve 19 (first flow path opening / closing means), an oil sump container 20 and a second open / close valve in parallel with the first capillary tube 17 (first flow path resistor). 21 (second flow path opening / closing means) and a second capillary tube 22 (second flow path resistor), and the outlet of the second capillary tube 22 (second flow path resistor) is connected pipe 18 To join. In addition, the refrigerant pipe 16a is provided with a first temperature sensor 23, which is located on the connection pipe 18 and has an outlet of the first capillary 17 (first flow path resistor) and a second capillary 22 (second flow). The second temperature sensor 24 is installed between the merging portions of the path resistors).

また、第１の温度センサー２３と第２の温度センサー２４の検知温度に応じて第１の開閉弁１９（第１の流路開閉手段）と第２の開閉弁２１（第２の流路開閉手段）の開閉を制御する第１の開閉弁制御手段２５を有している。 Further, the first on-off valve 19 (first channel opening / closing means) and the second on-off valve 21 (second channel opening / closing) according to the detected temperatures of the first temperature sensor 23 and the second temperature sensor 24. First on-off valve control means 25 for controlling the opening and closing of the means).

以上のように構成された冷凍サイクルについて、以下、図１を参照しながらその動作、作用を説明する。 The operation and action of the refrigeration cycle configured as described above will be described below with reference to FIG.

圧縮機１１から吐出された高圧ガス冷媒とオイルは、油分離器１２に流入し、高圧ガス冷媒とオイルに分離される。分離された高圧ガス冷媒は、凝縮器１３に流入し凝縮液化される。凝縮液化された高圧液冷媒は減圧手段１４により減圧され、低圧気液二相冷媒となり蒸発器１５に流入する。蒸発器１５に流入した気液二相冷媒は、吸熱し低圧ガス冷媒となり圧縮機１１に再度吸入される。 The high-pressure gas refrigerant and oil discharged from the compressor 11 flow into the oil separator 12 and are separated into the high-pressure gas refrigerant and oil. The separated high-pressure gas refrigerant flows into the condenser 13 and is condensed and liquefied. The condensed and liquefied high-pressure liquid refrigerant is decompressed by the decompression means 14, becomes a low-pressure gas-liquid two-phase refrigerant, and flows into the evaporator 15. The gas-liquid two-phase refrigerant that has flowed into the evaporator 15 absorbs heat, becomes low-pressure gas refrigerant, and is sucked into the compressor 11 again.

一方、油分離器１２で分離されたオイルは、一部のガス冷媒とともに第１の毛細管１７（第１の流路抵抗体）により減圧されながら接続管１８を通り冷媒配管１６ｄに流入し、低圧ガス冷媒とともに圧縮機１１に吸入される。 On the other hand, the oil separated by the oil separator 12 flows into the refrigerant pipe 16d through the connecting pipe 18 while being decompressed by the first capillary tube 17 (first flow path resistor) together with a part of the gas refrigerant. It is sucked into the compressor 11 together with the gas refrigerant.

このような冷媒とオイルの循環状態において、圧縮機１１から冷媒とともに吐出されるオイルは、油分離器１２で分離され、そのほとんどが、第１の毛細管１７（第１の流路抵抗体）と接続管１８を通り圧縮機１１の吸入管に返油されるが、一部は油分離器１２を通過し、熱交換器側に流出することになる。油分離器１２を通過したオイルは、凝縮器１３
、蒸発器１５、冷媒配管１６に一部滞留しながら圧縮機１１へと戻ってくる。 In such a circulation state of the refrigerant and oil, the oil discharged together with the refrigerant from the compressor 11 is separated by the oil separator 12, and most of the oil is separated from the first capillary tube 17 (first flow path resistor). Oil is returned to the suction pipe of the compressor 11 through the connection pipe 18, but a part passes through the oil separator 12 and flows out to the heat exchanger side. The oil that has passed through the oil separator 12 passes through the condenser 13.
Returning to the compressor 11 while partly staying in the evaporator 15 and the refrigerant pipe 16.

すなわち、冷媒配管１６が長い場合、オイルの滞留量が多くなり、短い場合は滞留量が少なくなる。このため、圧縮機１１には、滞留量が多くなる場合を考慮し、予め、最大滞留量を考慮したオイルが封入されている。 That is, when the refrigerant pipe 16 is long, the oil retention amount increases, and when it is short, the retention amount decreases. For this reason, the compressor 11 is preliminarily filled with oil in consideration of the maximum residence amount in consideration of the case where the residence amount increases.

したがって、このような圧縮機１１が、冷媒配管１６の短い冷凍サイクル装置に搭載された場合、圧縮機１１に封入されたオイル量は過剰となり、余剰オイルが発生し、凝縮器１３、蒸発器１５、冷媒配管１６に過剰にオイルが滞留し、熱交換器の伝熱性能低下や圧力損失の増加による性能低下の原因となる。 Therefore, when such a compressor 11 is mounted in a refrigeration cycle apparatus having a short refrigerant pipe 16, the amount of oil enclosed in the compressor 11 becomes excessive, generating excess oil, and the condenser 13 and the evaporator 15 The oil stays in the refrigerant pipe 16 excessively, which causes a decrease in heat transfer performance of the heat exchanger and a decrease in performance due to an increase in pressure loss.

過剰オイル量状態（余剰オイル発生状態）の運転になった場合、圧縮機１１へのオイルの返油量は増加し、圧縮機１１内のオイル量も増加することなる。圧縮機１１内のオイル量が増加すると、圧縮機１１からのオイル吐出量が増加し、油分離器１２へのオイル流入量も増加する。 When the operation is in an excessive oil amount state (excess oil generation state), the amount of oil returned to the compressor 11 increases and the amount of oil in the compressor 11 also increases. As the amount of oil in the compressor 11 increases, the amount of oil discharged from the compressor 11 increases and the amount of oil flowing into the oil separator 12 also increases.

油分離器１２では、流入した冷媒とオイルが分離され、分離されたオイルは、第１の毛細管１７（第１の流路抵抗体）および接続管１８を通じて冷媒配管１６ｄに流入するが、油分離器１２に流入するオイル量が過剰な場合、分離されるオイル量も増加するため、第１の毛細管１７（第１の流路抵抗体）では戻しきれず、油分離器１２底部に溜まり始める。 In the oil separator 12, the refrigerant and oil that have flowed are separated, and the separated oil flows into the refrigerant pipe 16 d through the first capillary tube 17 (first flow path resistor) and the connection pipe 18. When the amount of oil flowing into the separator 12 is excessive, the amount of oil to be separated also increases, so that the first capillary tube 17 (first flow path resistor) cannot return and starts to accumulate at the bottom of the oil separator 12.

油分離器１２に溜まり始めた余剰オイルが所定量以上になると、油分離器１２の分離性能が低下し、油分離器１２から凝縮器１３側へと流出するオイルが増加し、凝縮器１３、蒸発器１５、冷媒配管１６へのオイル滞留量が増加することになる。 When the excess oil that has started to accumulate in the oil separator 12 exceeds a predetermined amount, the separation performance of the oil separator 12 decreases, and the oil flowing out from the oil separator 12 toward the condenser 13 increases, The amount of oil staying in the evaporator 15 and the refrigerant pipe 16 increases.

次に、図２のフローチャートを参照しながらその開閉弁の動作を説明する。 Next, the operation of the on-off valve will be described with reference to the flowchart of FIG.

はじめに、第１の開閉弁１９（第１の流路開閉手段）を閉止し、第２の開閉弁２１（第２の流路開閉手段）を開放する（ステップＳ１）。次に、第１の温度センサー２２で圧縮機の吐出温度Ｔ１を計測し、第２の温度センサー２４で接続管温度Ｔ２を計測する（ステップＳ２）。 First, the first on-off valve 19 (first flow path opening / closing means) is closed, and the second on-off valve 21 (second flow path opening / closing means) is opened (step S1). Next, the discharge temperature T1 of the compressor is measured by the first temperature sensor 22, and the connecting pipe temperature T2 is measured by the second temperature sensor 24 (step S2).

このとき、過剰オイル状態で第１の毛細管１７（第１の流路抵抗体）を分離されたオイルのみが流通する場合、流通するオイルは、圧縮機１１から吐出された高温のオイルであり、この高温のオイルは、第１の毛細管１７（第１の流路抵抗体）を通過しても、膨張はしないため温度低下はほとんど無い。ここで、ステップＳ２で計測した圧縮機吐出温度Ｔ１と接続管温度Ｔ２の比較を行う（ステップＳ３）。 At this time, when only the separated oil flows through the first capillary tube 17 (first flow path resistor) in an excess oil state, the circulating oil is high-temperature oil discharged from the compressor 11, Even if this high-temperature oil passes through the first capillary tube 17 (first flow path resistor), it does not expand, so there is almost no temperature drop. Here, the compressor discharge temperature T1 measured in step S2 and the connecting pipe temperature T2 are compared (step S3).

検知された温度をもとに温度差ｔ１の比較を行い、所定の温度差ｔ１以下の場合、第１の開閉弁制御手段２５は、第１の開閉弁１９（第１の流路開閉手段）を開放する（ステップＳ４）。 The temperature difference t1 is compared based on the detected temperature. If the temperature difference t1 is equal to or less than the predetermined temperature difference t1, the first on-off valve control means 25 is connected to the first on-off valve 19 (first flow path opening / closing means). Is released (step S4).

ステップＳ４で第１の開閉弁１９（第１の流路開閉手段）を開放すると、油分離器１２に溜まっていた余剰オイルは、油溜め容器２０と第２の毛細管２２（第２の流路抵抗体）を通じて接続管１８に流れ始める。このとき、油溜め容器２０の下流部には、第２の毛細管２２（第２の流路抵抗体）が接続されているため、油溜め容器２０に流入するオイルは、油溜め容器２０内に徐々に溜まり始める。これにより、油分離器１２内の余剰オイル量は減少し始める。 When the first opening / closing valve 19 (first flow path opening / closing means) is opened in step S4, the excess oil accumulated in the oil separator 12 is stored in the oil reservoir 20 and the second capillary 22 (second flow path). It begins to flow to the connecting pipe 18 through the resistor. At this time, since the second capillary 22 (second flow path resistor) is connected to the downstream portion of the oil reservoir container 20, the oil flowing into the oil reservoir container 20 enters the oil reservoir container 20. It begins to accumulate gradually. Thereby, the surplus oil amount in the oil separator 12 starts to decrease.

このような状態で、ステップＳ２、ステップＳ３、ステップＳ４を繰り返すことで、油分離器１２内の余剰オイルが減少すると、第１の毛細管１７（第１の流路抵抗体）には、オイルとともに高圧ガス冷媒が流入し始める。高圧ガス冷媒が第１の毛細管１７（第１の流路抵抗体）を流通すると、冷媒ガスは減圧膨張し、その温度は低下する。これは、油分離器１２内には、余剰オイルが溜まっていないことを示す。 In such a state, when the excess oil in the oil separator 12 is reduced by repeating Step S2, Step S3, and Step S4, the first capillary 17 (first flow path resistor) is put together with the oil. High-pressure gas refrigerant begins to flow. When the high-pressure gas refrigerant flows through the first capillary tube 17 (first flow path resistor), the refrigerant gas expands under reduced pressure, and its temperature decreases. This indicates that excess oil is not accumulated in the oil separator 12.

このとき、ステップＳ３で、所定の温度差ｔ１以上の場合、まず、第１の開閉弁（第１の流路開閉手段）の状態を確認する（ステップＳ５）。 At this time, if the temperature difference is equal to or greater than the predetermined temperature difference t1 in step S3, first, the state of the first on-off valve (first flow path opening / closing means) is confirmed (step S5).

ステップＳ５で、第１の開閉弁１９（第１の流路開閉手段）が開放状態にある場合、油溜め容器２０への余剰オイルの回収運転状態にあることを示し、この状態で、所定の温度差ｔ１以上となっているので、油分離器１２内の余剰オイルが無くなったと判断し、第１の開閉弁１９（第１の流路開閉手段）と第２の開閉弁２１（第２の流路開閉手段）をともに閉止する（ステップＳ６）。 In step S5, when the first on-off valve 19 (first flow path opening / closing means) is in the open state, it indicates that the surplus oil is being collected into the oil reservoir 20 and in this state, Since the temperature difference is equal to or greater than t1, it is determined that there is no excess oil in the oil separator 12, and the first opening / closing valve 19 (first flow path opening / closing means) and the second opening / closing valve 21 (second Both the channel opening / closing means are closed (step S6).

一方、ステップＳ５で既に第１の開閉弁１９（第１の流路開閉手段）が閉止状態にある場合は、油分離器１２内には余剰オイルは、発生していない状態であることを示し、引き続き、ステップＳ１、ステップＳ２、ステップＳ３、ステップＳ５を繰り返し、余剰オイル発生の監視を継続する。 On the other hand, if the first on-off valve 19 (first flow path opening / closing means) is already closed in step S5, it indicates that no excess oil is generated in the oil separator 12. Subsequently, Step S1, Step S2, Step S3, and Step S5 are repeated, and monitoring of excess oil generation is continued.

以上の様な動作を繰り返すことにより、余剰オイルの発生を確実に検知し、余剰オイルが発生した場合は、第１の開閉弁１９（第１の流路開閉手段）および第２の開閉弁２１（第２の流路開閉手段）の開閉制御により油分離器１２からのオイル戻り量を制御して、余剰オイルが発生した場合は、油溜め容器２０に余剰オイルを回収し、油分離器１２から凝縮器１３、蒸発器１５、冷媒配管１６に流出するオイル量を軽減でき、凝縮器１３、蒸発器１５、冷媒配管１６へのオイル滞留量を低減することができる。 By repeating the operation as described above, the generation of surplus oil is reliably detected, and when surplus oil is generated, the first on-off valve 19 (first flow path opening / closing means) and the second on-off valve 21 are detected. When the oil return amount from the oil separator 12 is controlled by opening / closing control of the (second flow path opening / closing means) and surplus oil is generated, the surplus oil is recovered in the oil sump container 20 and the oil separator 12 is recovered. The amount of oil flowing out from the condenser 13, the evaporator 15, and the refrigerant pipe 16 can be reduced, and the amount of oil remaining in the condenser 13, the evaporator 15, and the refrigerant pipe 16 can be reduced.

また、余剰オイルの回収完了状態で運転を完了した場合、第１の開閉弁１９（第１の流路開閉手段）および第２の開閉弁２１（第２の流路開閉手段）が通電開放の仕様とした場合、回収した余剰オイルを保持したまま再起動でき、効率よく運転を再開できる。 In addition, when the operation is completed in a state where surplus oil has been collected, the first on-off valve 19 (first flow path opening / closing means) and the second on-off valve 21 (second flow path opening / closing means) are turned off. In the case of the specification, it can be restarted while retaining the recovered surplus oil, and operation can be resumed efficiently.

更に、停止中に油溜め容器２０への余分な冷媒の溜まり込みも無く信頼性能向上を図ることができる。 Furthermore, there is no accumulation of excess refrigerant in the oil sump container 20 during the stop, and the reliability performance can be improved.

また、余剰オイルを回収するための第１の開閉弁１９（第１の流路開閉手段）、油溜め容器２０、第２の開閉弁２１（第２の流路開閉手段）は、第１の毛細管１７（第１の流路抵抗体）に並列に配置されているため、第１の開閉弁１９（第１の流路開閉手段）もしくは第２の開閉弁２１（第２の流路開閉手段）が故障した場合でも、通常の油分離器１２からのオイル戻りは確保できるため、圧縮機１１の信頼性を確保することができる。 Further, the first on-off valve 19 (first flow path opening / closing means), the oil reservoir 20 and the second on-off valve 21 (second flow path opening / closing means) for recovering excess oil are provided in the first Since the capillaries 17 (first flow path resistors) are arranged in parallel, the first on-off valve 19 (first flow path opening / closing means) or the second on-off valve 21 (second flow path opening / closing means). ), The oil return from the normal oil separator 12 can be ensured, so that the reliability of the compressor 11 can be ensured.

なお、油溜め容器２０の入口および出口に設置されている第１の開閉弁１９（第１の流路開閉手段）および第２の開閉弁２１（第２の流路開閉手段）は、どちらか一方でも良く、余剰オイルの回収について同様の効果は得られる。 Note that either the first on-off valve 19 (first flow path opening / closing means) and the second on-off valve 21 (second flow path opening / closing means) installed at the inlet and outlet of the oil reservoir 20 are either. One side may be sufficient and the same effect is acquired about collection | recovery of excess oil.

（実施の形態２）
図３は、本発明の第２の実施の形態における冷凍サイクル図、図４は、開閉弁制御のフローチャートを示す。 (Embodiment 2)
FIG. 3 is a refrigeration cycle diagram according to the second embodiment of the present invention, and FIG. 4 is a flowchart of on-off valve control.

本実施の形態の冷凍サイクルは、第１の温度センサー２６を圧縮機１１の吸入管（接続管１８と冷媒配管１６ｄの接続位置よりも圧縮機側）に設置し、第２の温度センサー２７
を接続管１８と冷媒配管１６ｄの接続位置より上流側（蒸発器１５側）に設置し、第２の開閉弁制御手段２８を設けたものである。 In the refrigeration cycle of the present embodiment, the first temperature sensor 26 is installed on the suction pipe of the compressor 11 (on the compressor side with respect to the connection position of the connection pipe 18 and the refrigerant pipe 16d), and the second temperature sensor 27 is installed.
Is installed on the upstream side (evaporator 15 side) from the connection position of the connection pipe 18 and the refrigerant pipe 16d, and the second on-off valve control means 28 is provided.

以上のように構成された冷凍サイクルについて、以下、図３を参照しながらその動作、作用を説明する。冷媒とオイルの流れについては、実施の形態１と同様であり、説明は省略する。 The operation and action of the refrigeration cycle configured as described above will be described below with reference to FIG. About the flow of a refrigerant and oil, it is the same as that of Embodiment 1, and explanation is omitted.

はじめに、第１の開閉弁１９（第１の流路開閉手段）を閉止し、第２の開閉弁２１（第２の流路開閉手段）を開放する（ステップＳ１）。 First, the first on-off valve 19 (first flow path opening / closing means) is closed, and the second on-off valve 21 (second flow path opening / closing means) is opened (step S1).

次に、第１の温度センサー２６で圧縮機の吸入温度Ｔ３を計測し、第２の温度センサー２７で戻りオイルが流入する位置の上流側の冷媒配管１６ｄの温度Ｔ４を計測する（ステップＳ２）。 Next, the first temperature sensor 26 measures the suction temperature T3 of the compressor, and the second temperature sensor 27 measures the temperature T4 of the refrigerant pipe 16d upstream of the position where the return oil flows (step S2). .

このとき、過剰オイル状態で第１の毛細管１７（第１の流路抵抗体）を分離されたオイルのみが流通する場合、流通するオイルは、圧縮機１１から吐出された高温のオイルであり、この高温のオイルは、第１の毛細管１７（第１の流路抵抗体）を通過しても、膨張はしないため温度低下はほとんど無い。ここで、ステップＳ２で計測した圧縮機吸入温度Ｔ３と戻りオイルが流入する位置の上流側の冷媒配管１６ｄの温度Ｔ４の比較を行う（ステップＳ３）。 At this time, when only the separated oil flows through the first capillary tube 17 (first flow path resistor) in an excess oil state, the circulating oil is high-temperature oil discharged from the compressor 11, Even if this high-temperature oil passes through the first capillary tube 17 (first flow path resistor), it does not expand, so there is almost no temperature drop. Here, the compressor suction temperature T3 measured in step S2 is compared with the temperature T4 of the refrigerant pipe 16d on the upstream side of the position where the return oil flows (step S3).

検知された温度をもとに温度差ｔ２の比較を行い、所定の温度差ｔ２以上の場合、第１の開閉弁制御手段２５は、第１の開閉弁１９（第１の流路開閉手段）を開放する（ステップＳ４）。 The temperature difference t2 is compared based on the detected temperature. If the temperature difference t2 is equal to or greater than the predetermined temperature difference t2, the first on-off valve control means 25 is connected to the first on-off valve 19 (first flow path opening / closing means). Is released (step S4).

ステップＳ４で第１の開閉弁１９（第１の流路開閉手段）を開放すると、油分離器１２に溜まっていた余剰オイルは、油溜め容器２０と第２の毛細管２２を通じて接続管１８に流れ始める。このとき、油溜め容器２０の下流部には、第２の毛細管２２（第２の流路抵抗体）が接続されているため、油溜め容器２０に流入するオイルは、油溜め容器２０内に徐々に溜まり始める。これにより、油分離器１２内の余剰オイル量は減少し始める。 When the first opening / closing valve 19 (first flow path opening / closing means) is opened in step S4, surplus oil accumulated in the oil separator 12 flows to the connecting pipe 18 through the oil reservoir 20 and the second capillary tube 22. start. At this time, since the second capillary 22 (second flow path resistor) is connected to the downstream portion of the oil reservoir container 20, the oil flowing into the oil reservoir container 20 enters the oil reservoir container 20. It begins to accumulate gradually. Thereby, the surplus oil amount in the oil separator 12 starts to decrease.

このような状態で、ステップＳ２、ステップＳ３、ステップＳ４を繰り返すことで、油分離器１２内の余剰オイルが減少すると、第１の毛細管１７（第１の流路抵抗体）には、
オイルとともに高圧ガス冷媒が流入し始める。高圧ガス冷媒が第１の毛細管１７（第１の流路抵抗体）を流通すると、冷媒ガスは減圧膨張し、その温度は低下する。これは、油分離器１２内には、余剰オイルが溜まっていないことを示す。 When the excess oil in the oil separator 12 is reduced by repeating Step S2, Step S3, and Step S4 in such a state, the first capillary 17 (first flow path resistor)
High-pressure gas refrigerant begins to flow in along with the oil. When the high-pressure gas refrigerant flows through the first capillary tube 17 (first flow path resistor), the refrigerant gas expands under reduced pressure, and its temperature decreases. This indicates that excess oil is not accumulated in the oil separator 12.

このとき、ステップＳ３で、所定の温度差ｔ２以下の場合、まず、第１の開閉弁（第１の流路開閉手段）の状態を確認する（ステップＳ５）。 At this time, if the temperature difference is equal to or smaller than the predetermined temperature difference t2 in step S3, first, the state of the first on-off valve (first flow path opening / closing means) is confirmed (step S5).

ステップＳ５で、第１の開閉弁１９（第１の流路開閉手段）が開放状態にある場合、油溜め容器２０への余剰オイルの回収運転状態にあることを示し、この状態で、所定の温度差ｔ１以上となっているので、油分離器１２内の余剰オイルが無くなったこと判断し、第１の開閉弁１９（第１の流路開閉手段）と第２の開閉弁２１（第２の流路開閉手段）をともに閉止する（ステップＳ６）。 In step S5, when the first on-off valve 19 (first flow path opening / closing means) is in the open state, it indicates that the surplus oil is being collected into the oil reservoir 20 and in this state, Since the temperature difference is equal to or greater than t1, it is determined that there is no excess oil in the oil separator 12, and the first opening / closing valve 19 (first flow path opening / closing means) and the second opening / closing valve 21 (second Are closed together (step S6).

以上のように、本発明にかかる冷凍サイクル装置は、冷凍サイクル中の余剰オイルの発生を確実に検知するとともに熱交換器側に流出する余剰オイル量を軽減し、凝縮器、蒸発器、冷媒配管に滞留する余剰オイル量を低減することが可能となるので、空調機用冷凍サイクル装置、カーエアコン、ヒートポンプ給湯機等のさまざまな冷凍サイクル装置に適用できる。 As described above, the refrigeration cycle apparatus according to the present invention reliably detects the generation of excess oil in the refrigeration cycle and reduces the amount of excess oil flowing out to the heat exchanger side. Therefore, it can be applied to various refrigeration cycle apparatuses such as an air conditioner refrigeration cycle apparatus, a car air conditioner, and a heat pump water heater.

１１圧縮機
１２油分離器
１３凝縮器
１４減圧手段
１５蒸発器
１６冷媒配管
１７第１の毛細管
１８第１の接続管
１９第１の開閉弁
２０油溜め容器
２１第２の開閉弁
２２第２の毛細管
２３第１の温度センサー
２４第２の温度センサー
２５第１の開閉弁制御手段
２６第１の温度センサー
２７第２の温度センサー
２８第２の開閉弁制御手段 DESCRIPTION OF SYMBOLS 11 Compressor 12 Oil separator 13 Condenser 14 Decompression means 15 Evaporator 16 Refrigerant piping 17 1st capillary 18 First connection pipe 19 1st on-off valve 20 Oil sump container 21 2nd on-off valve 22 2nd Capillary tube 23 First temperature sensor 24 Second temperature sensor 25 First on-off valve control means 26 First temperature sensor 27 Second temperature sensor 28 Second on-off valve control means

Claims

圧縮機の吐出側を、油分離器、第１の流路抵抗体を介して前記圧縮機の吸入側に接続する接続管と、前記油分離器に連通し前記第１の流路抵抗体に並列に、第１の流路開閉手段、油溜め容器、第２の流路抵抗体を順次直列に接続する接続管とを備えたことを特徴とする冷凍サイクル装置。 The discharge side of the compressor is connected to the suction side of the compressor via an oil separator and a first flow path resistor, and the first flow path resistor communicates with the oil separator. A refrigeration cycle apparatus comprising a first pipe opening / closing means, an oil reservoir, and a connecting pipe for sequentially connecting a second passage resistor in series in parallel.

圧縮機の吐出側を、油分離器、第１の流路抵抗体を介して前記圧縮機の吸入側に接続する接続管と、前記油分離器に連通し前記第１の流路抵抗体に並列に、油溜め容器、第２の流路開閉手段、第２の流路抵抗体を順次直列に接続する接続管とを備えたことを特徴とする冷凍サイクル装置。 The discharge side of the compressor is connected to the suction side of the compressor via an oil separator and a first flow path resistor, and the first flow path resistor communicates with the oil separator. A refrigeration cycle apparatus comprising an oil sump container, a second channel opening / closing means, and a connecting pipe for sequentially connecting a second channel resistor in series in parallel.

圧縮機の吐出側を、油分離器、第１の流路抵抗体を介して前記圧縮機の吸入側に接続する接続管と、前記油分離器に連通し前記第１の流路抵抗体に並列に、第１の流路開閉手段、油溜め容器、第２の流路開閉手段、第２の流路抵抗体を順次直列に接続する接続管とを備えたことを特徴とする冷凍サイクル装置。 The discharge side of the compressor is connected to the suction side of the compressor via an oil separator and a first flow path resistor, and the first flow path resistor communicates with the oil separator. A refrigeration cycle apparatus comprising a first flow path opening / closing means, an oil reservoir, a second flow path opening / closing means, and a connecting pipe for connecting the second flow path resistors in series in parallel. .

圧縮機の吐出管に設けた第１の温度センサーと、第１の流路抵抗体出口側の接続管に設けた第２の温度センサーと、制御手段とを備え、前記第１の温度センサーと前記第２の温度センサーとで検知された温度差が所定値以下の場合には、前記第１の流路開閉手段を開放し、前記所定値より大きい場合には、閉止することを特徴とする請求項１に記載の冷凍サイクル装置。 A first temperature sensor provided in a discharge pipe of the compressor; a second temperature sensor provided in a connection pipe on the outlet side of the first flow path resistor; and a control means; When the temperature difference detected by the second temperature sensor is less than a predetermined value, the first flow path opening / closing means is opened, and when the temperature difference is larger than the predetermined value, it is closed. The refrigeration cycle apparatus according to claim 1.

圧縮機の吐出管に設けた第１の温度センサーと、第１の流路抵抗体出口側の接続管に設けた第２の温度センサーと、制御手段とを備え、前記第１の温度センサーと前記第２の温度センサーとで検知された温度差が所定値以下の場合には、前記第２の流路開閉手段を開放し、前記所定値より大きい場合には、閉止することを特徴とする請求項２に記載の冷凍サイクル装置。 A first temperature sensor provided in a discharge pipe of the compressor; a second temperature sensor provided in a connection pipe on the outlet side of the first flow path resistor; and a control means; The second flow path opening / closing means is opened when the temperature difference detected by the second temperature sensor is equal to or smaller than a predetermined value, and is closed when the temperature difference is larger than the predetermined value. The refrigeration cycle apparatus according to claim 2.

圧縮機の吐出管に設けた第１の温度センサーと、第１の流路抵抗体出口側の接続管に設けた第２の温度センサーと、制御手段とを備え、前記第１の温度センサーと前記第２の温度センサーとで検知された温度差が所定値以下の場合には、前記第１の流路開閉手段と前記第２の流路開閉手段を開放し、前記所定値より大きい場合には、閉止することを特徴とする請求項３に記載の冷凍サイクル装置。 A first temperature sensor provided in a discharge pipe of the compressor; a second temperature sensor provided in a connection pipe on the outlet side of the first flow path resistor; and a control means; When the temperature difference detected by the second temperature sensor is equal to or smaller than a predetermined value, the first flow path opening / closing means and the second flow path opening / closing means are opened and the temperature difference is larger than the predetermined value. The refrigeration cycle apparatus according to claim 3, wherein the refrigeration cycle apparatus is closed.

圧縮機の吸入管に設けた第１の温度センサーと、蒸発器の出口側に設けた第２の温度センサーと、制御手段とを備え、前記第１の温度センサーと前記第２の温度センサーとで検知された温度差が所定値以上の場合には、前記第１の流路開閉手段を開放し、前記所定値より小さい場合には、閉止することを特徴とする請求項１に記載の冷凍サイクル装置。 A first temperature sensor provided on a suction pipe of the compressor; a second temperature sensor provided on an outlet side of the evaporator; and a control unit, wherein the first temperature sensor, the second temperature sensor, 2. The refrigeration according to claim 1, wherein when the temperature difference detected in step 1 is equal to or greater than a predetermined value, the first flow path opening / closing means is opened, and when the temperature difference is smaller than the predetermined value, it is closed. Cycle equipment.

圧縮機の吸入管に設けた第１の温度センサーと、蒸発器の出口側に設けた第２の温度センサーと、制御手段とを備え、前記第１の温度センサーと前記第２の温度センサーとで検知された温度差が所定値以上の場合には、前記第２の流路開閉手段を開放し、前記所定値より小さい場合には、閉止することを特徴とする請求項２に記載の冷凍サイクル装置。 A first temperature sensor provided on a suction pipe of the compressor; a second temperature sensor provided on an outlet side of the evaporator; and a control unit, wherein the first temperature sensor, the second temperature sensor, The refrigeration according to claim 2, wherein when the temperature difference detected in step (b) is greater than or equal to a predetermined value, the second flow path opening / closing means is opened, and when the temperature difference is smaller than the predetermined value, the second flow path opening / closing means is closed. Cycle equipment.

圧縮機の吸入管に設けた第１の温度センサーと、蒸発器の出口側に設けた第２の温度センサーと、制御手段とを備え、前記第１の温度センサーと前記第２の温度センサーとで検知された温度差が所定値以上の場合には、前記第１の流路開閉手段と前記第２の流路開閉手段とを開放し、前記所定値より小さい場合には、閉止することを特徴とする請求項３に記載の冷凍サイクル装置。 A first temperature sensor provided on a suction pipe of the compressor; a second temperature sensor provided on an outlet side of the evaporator; and a control unit, wherein the first temperature sensor, the second temperature sensor, If the temperature difference detected in step (b) is greater than or equal to a predetermined value, the first flow path opening / closing means and the second flow path opening / closing means are opened. If the temperature difference is smaller than the predetermined value, the first flow path opening / closing means is closed. The refrigeration cycle apparatus according to claim 3, wherein