JPH0552430A - Refrigerating machine - Google Patents
Refrigerating machineInfo
- Publication number
- JPH0552430A JPH0552430A JP3209659A JP20965991A JPH0552430A JP H0552430 A JPH0552430 A JP H0552430A JP 3209659 A JP3209659 A JP 3209659A JP 20965991 A JP20965991 A JP 20965991A JP H0552430 A JPH0552430 A JP H0552430A
- Authority
- JP
- Japan
- Prior art keywords
- refrigerant
- compressor
- flow rate
- valve
- evaporator
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B41/00—Fluid-circulation arrangements
- F25B41/20—Disposition of valves, e.g. of on-off valves or flow control valves
- F25B41/22—Disposition of valves, e.g. of on-off valves or flow control valves between evaporator and compressor
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Mechanical Engineering (AREA)
- Thermal Sciences (AREA)
- General Engineering & Computer Science (AREA)
- Devices That Are Associated With Refrigeration Equipment (AREA)
Abstract
Description
【0001】[0001]
【産業上の利用分野】本発明は、例えば水を冷却媒体と
して半導体素子の冷却を行う水冷式冷却装置,工作機械
用の切削油の冷却を行う冷却装置などの、被冷却体の精
密な温度制御が必要な装置に用いられる冷凍機に係わ
り、特に冷凍機に搭載された圧縮機の吸込圧力の過度の
低下を防止するよう改良した構成に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a precise temperature of an object to be cooled, such as a water cooling type cooling device for cooling a semiconductor element using water as a cooling medium and a cooling device for cooling cutting oil for machine tools. The present invention relates to a refrigerator used in a device that needs to be controlled, and more particularly to an improved structure for preventing an excessive decrease in suction pressure of a compressor mounted on the refrigerator.
【0002】[0002]
【従来の技術】半導体素子の冷却装置では、半導体素子
の使用温度が厳しく規制されていることから、半導体素
子の発熱量の変動に対応して冷却液体である冷却水や冷
却油の精密な温度制御が要求される。図4はこのような
冷却装置に使用されている従来技術による冷凍機の冷媒
回路図である。図4において、1は、冷媒1aを吸入口
から吸い込み加圧圧縮して吐出口から吐出する圧縮機、
2は圧縮機1で圧縮されて高温となった冷媒1aを冷却
する凝縮器、3は前記圧縮機1で圧縮され高圧となった
冷媒1aを膨張させる膨張弁、4は冷媒1aが蒸発する
ことで冷熱を発生し、被冷却体である冷却液体を冷却す
る蒸発器、8は冷却液体が通流する管路、5は蒸発器4
と前記圧縮機1の吸入口の間に挿入された流量調整弁、
6は冷却液体管路8に配設され冷却液体の温度を検出す
る温度センサ、7は温度センサ6の出力を入力信号とし
て流量調整弁5に弁開度信号を出力する温度制御器であ
る。2. Description of the Related Art In a semiconductor element cooling device, since the operating temperature of the semiconductor element is strictly regulated, the precise temperature of the cooling water or the cooling oil, which is the cooling liquid, is adjusted in response to the fluctuation of the heat value of the semiconductor element. Control is required. FIG. 4 is a refrigerant circuit diagram of a conventional refrigerator used in such a cooling device. In FIG. 4, reference numeral 1 denotes a compressor for sucking the refrigerant 1a from the suction port, compressing it under pressure, and discharging it from the discharge port.
Reference numeral 2 is a condenser for cooling the refrigerant 1a that has been compressed by the compressor 1 and has a high temperature, 3 is an expansion valve for expanding the refrigerant 1a that has been compressed by the compressor 1 and has a high pressure, and 4 is that the refrigerant 1a is evaporated. To cool the cooling liquid, which is the object to be cooled, 8 is a conduit through which the cooling liquid flows, and 5 is an evaporator 4.
And a flow rate adjusting valve inserted between the suction port of the compressor 1 and
Reference numeral 6 denotes a temperature sensor arranged in the cooling liquid pipe 8 for detecting the temperature of the cooling liquid, and 7 denotes a temperature controller for outputting a valve opening signal to the flow rate adjusting valve 5 using the output of the temperature sensor 6 as an input signal.
【0003】上記の構成において、まず、温度制御器7
と流量調整弁5との制御系により、蒸発器4における冷
却液体の温度を温度センサ6で検出して、流量調整弁5
の弁開度を加減し冷媒1aの通流量を加減することで冷
却液体の温度制御が行われる。すなわち、例えば半導体
素子が発生する損失が減少することで熱負荷が減少し、
冷却液体の温度が低下し始めると、温度センサ6がこの
温度変化を検知して流量調整弁5の弁開度を絞り冷媒1
aの通流量を低減し、冷凍機の冷凍能力を熱負荷とバラ
ンスさせるように低減させる。これにより熱負荷の如何
にかかわらず、冷却液体の温度を精密に制御することが
できる。In the above configuration, first, the temperature controller 7
The temperature sensor 6 detects the temperature of the cooling liquid in the evaporator 4 by the control system of the flow rate adjusting valve 5 and the flow rate adjusting valve 5.
The temperature control of the cooling liquid is performed by adjusting the valve opening degree and the flow rate of the refrigerant 1a. That is, for example, the heat load is reduced by reducing the loss generated by the semiconductor element,
When the temperature of the cooling liquid starts to decrease, the temperature sensor 6 detects this temperature change and throttles the valve opening of the flow rate adjusting valve 5 to cool the refrigerant 1
The flow rate of a is reduced and the refrigerating capacity of the refrigerator is reduced so as to balance with the heat load. As a result, the temperature of the cooling liquid can be precisely controlled regardless of the heat load.
【0004】[0004]
【発明が解決しようとする課題】前述した従来技術によ
る冷凍機は、冷却液体の温度を精密に制御することがで
きるが、流量調整弁の弁開度は熱負荷に応じて全開から
全閉まで変化されうる。したがって温度制御器の温度設
定値が冷却液体の現在温度よりも高い温度に設定されて
いる場合や、何らかの原因で熱負荷が大幅に低下した場
合等では、温度制御器からの信号により流量調整弁の弁
開度は全閉または全閉に近い状態に絞られることがあ
る。流量調整弁の弁開度が全閉または全閉に近い状態に
絞られると、圧縮機の吸込圧力は負圧となるので、圧縮
機が吐出する冷媒ガスに過度の温度上昇をもたらすこと
となり、冷媒ガスの分解や圧縮機駆動用電動機の焼損な
どを生じるという問題がある。この問題の対策として、
温度制御器にリミッタを設けて流量調整弁を所望の開度
以下に閉じなくする方法が考えられるが、この場合には
汎用の温度制御器はリミッタを保有しておらず、また所
望の開度も個々の冷却装置により異なることから、高価
な専用の温度制御器を使用しなければならないという問
題がある。The refrigerator according to the prior art described above is capable of precisely controlling the temperature of the cooling liquid, but the valve opening of the flow rate adjusting valve varies from fully open to fully closed depending on the heat load. Can be changed. Therefore, if the temperature setting value of the temperature controller is set higher than the current temperature of the cooling liquid, or if the heat load is significantly reduced for some reason, etc., the flow rate control valve will be activated by the signal from the temperature controller. The valve opening of may be closed or may be close to a closed state. When the valve opening of the flow rate adjusting valve is fully closed or closed to a state close to full closing, the suction pressure of the compressor becomes a negative pressure, which causes an excessive temperature rise in the refrigerant gas discharged from the compressor. There is a problem that the refrigerant gas is decomposed and the compressor driving electric motor is burnt out. As a measure against this problem,
A possible method is to provide a limiter on the temperature controller to prevent the flow control valve from closing below the desired opening, but in this case a general-purpose temperature controller does not have a limiter and the desired opening However, there is a problem in that an expensive dedicated temperature controller must be used since each cooling device also differs depending on the individual cooling device.
【0005】本発明は、前述の従来技術の問題点に鑑み
なされたものであり、その目的は流量調整弁と並列に冷
媒の抵抗手段を備えたバイパス流路を配設することで、
リミッタを持たない汎用温度制御器を採用しても、圧縮
機の吸込圧力が過度に低下する問題を排除できる冷却装
置用の冷凍機を提供することにある。The present invention has been made in view of the above-mentioned problems of the prior art, and an object thereof is to dispose a bypass flow passage having a resistance means for refrigerant in parallel with a flow rate adjusting valve,
It is an object of the present invention to provide a refrigerator for a cooling device that can eliminate the problem that the suction pressure of the compressor is excessively reduced even if a general-purpose temperature controller having no limiter is adopted.
【0006】[0006]
【課題を解決するための手段】本発明では前述の目的
は、 1)冷媒を蒸発させることで冷熱を発生する蒸発器と、
この蒸発器で蒸発して低圧となった冷媒を吸入口から吸
い込み加圧圧縮して吐出口から吐出する圧縮機と、この
圧縮機で圧縮されて高温となった冷媒を冷却する凝縮器
と、この凝縮器の下流に接続され前記圧縮機で圧縮され
高圧となった冷媒を膨張させる膨張弁と、前記蒸発器と
前記圧縮機の吸入口の間に挿入された前記冷媒の流量を
調整するための流量調整弁とを備えた冷凍機において、
前記流量調整弁と並列に冷媒の抵抗手段を備えたバイパ
ス流路を配設したこと、また 2)前記1項の手段において、抵抗手段はキャピラリー
チューブであること、さらにまた 3)前記1項の手段において、抵抗手段は手動調整弁で
あること、により達成される。In the present invention, the above-mentioned objects are as follows: 1) an evaporator for generating cold heat by evaporating a refrigerant;
A compressor that sucks in and compresses the low-pressure refrigerant evaporated in this evaporator from the suction port and discharges it from the discharge port; and a condenser that cools the high-temperature refrigerant compressed by this compressor, An expansion valve connected downstream of the condenser for expanding the high-pressure refrigerant compressed by the compressor, and for adjusting the flow rate of the refrigerant inserted between the evaporator and the suction port of the compressor. In the refrigerator equipped with the flow rate adjusting valve of
A bypass flow path provided with a resistance means for the refrigerant is arranged in parallel with the flow rate adjusting valve, and 2) in the means of the above item 1, the resistance means is a capillary tube, and 3) in the above item 1. In the means, the resistance means is achieved by being a manually regulated valve.
【0007】[0007]
【作用】本発明においては前述の構成として、流量調整
弁と並列に冷媒の抵抗手段を備えたバイパス流路を配設
したことにより、流量調整弁がたとえ全閉されたとして
も、抵抗手段を介して少量の冷媒が圧縮機に流入するの
で、圧縮機の吸込圧力が負圧になることは解消される。In the present invention, the bypass means having the resistance means for the refrigerant is arranged in parallel with the flow rate adjusting valve in the above-mentioned configuration, so that the resistance means is provided even if the flow rate adjusting valve is fully closed. Since a small amount of refrigerant flows into the compressor via the above, the suction pressure of the compressor is prevented from becoming a negative pressure.
【0008】[0008]
【実施例】以下本発明の実施例を図面を参照して詳細に
説明する。図1は本発明の一実施例による冷凍機の冷媒
回路図である。図4の従来例と同一部分には同じ符号を
付して、その説明を省略する。図1において、9は流量
調整弁5と並列に形成する冷媒1aのバイパス流路10
に接続された冷媒1aの抵抗手段としてのキャピラリー
チューブである。本発明では前述の構成としたので、例
えば何らかの原因で熱負荷が大幅に低下して温度制御器
7の信号で流量調整弁5が全閉された場合においても、
少量の冷媒1aがキャピラリーチューブ9を通流して圧
縮機に流入するので、圧縮機の吸込圧力が負圧になるこ
とは解消されて、圧縮機は正常な運転を継続する。この
とき、冷却液体の温度は徐々に設定値に戻る。なお、キ
ャピラリーチューブ9の内径や長さは、流量調整弁5の
全閉時に、圧縮機の吸込圧力が負圧とならず、したがっ
て圧縮機の吐出する冷媒ガスが許容される温度上昇値を
維持する使用限界を越えない程度に、冷媒1aが流れる
ように定める。Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a refrigerant circuit diagram of a refrigerator according to an embodiment of the present invention. The same parts as those in the conventional example of FIG. 4 are designated by the same reference numerals, and the description thereof will be omitted. In FIG. 1, reference numeral 9 denotes a bypass flow passage 10 for the refrigerant 1a formed in parallel with the flow rate adjusting valve 5.
It is a capillary tube as a resistance means of the refrigerant 1a connected to. Since the present invention has the above-described configuration, for example, even when the heat load is significantly reduced for some reason and the flow rate adjusting valve 5 is fully closed by the signal of the temperature controller 7,
Since a small amount of the refrigerant 1a flows through the capillary tube 9 and flows into the compressor, the suction pressure of the compressor is prevented from becoming a negative pressure, and the compressor continues normal operation. At this time, the temperature of the cooling liquid gradually returns to the set value. The inner diameter and the length of the capillary tube 9 are such that the suction pressure of the compressor does not become a negative pressure when the flow rate adjusting valve 5 is fully closed, so that the temperature rise value at which the refrigerant gas discharged from the compressor is allowed is maintained. The refrigerant 1a is set to flow so as not to exceed the usage limit.
【0009】図2は本発明の異なる実施例による冷凍機
の冷媒回路図である。図1の本発明の一実施例および図
4の従来例と同一部分には同じ符号を付して、その説明
を省略する。図2において、11はバイパス回路10に
接続された冷媒1aの抵抗手段としての手動調整弁であ
る。本構成の場合も、全述の図1による本発明の一実施
例の場合と同様に動作する。しかも手動調整弁11の弁
開度を適度に調整することで、流量調整弁5の全閉時に
バイパス流路10を通流する冷媒1aの流量を、冷却装
置の運転状況に応じて最適に設定することができること
で、一層好ましい効果を得ることが出来る。FIG. 2 is a refrigerant circuit diagram of a refrigerator according to another embodiment of the present invention. The same parts as those of the embodiment of the present invention shown in FIG. 1 and the conventional example shown in FIG. 4 are designated by the same reference numerals and the description thereof will be omitted. In FIG. 2, reference numeral 11 is a manual adjustment valve that is connected to the bypass circuit 10 and serves as a resistance unit for the refrigerant 1a. Also in the case of this configuration, the same operation as in the case of the embodiment of the present invention according to FIG. Moreover, by appropriately adjusting the valve opening degree of the manual adjustment valve 11, the flow rate of the refrigerant 1a flowing through the bypass passage 10 when the flow rate adjustment valve 5 is fully closed is optimally set according to the operating condition of the cooling device. It is possible to obtain a more preferable effect.
【0010】図3は本発明の一実施例を応用した冷凍機
の冷媒回路図である。図1の本発明の一実施例との相違
点は、図1の本発明の一実施例にすでに特開昭61−7
6853号公報で公知の冷凍機の容量制御幅を拡大する
技術を組み合わせたものである。すなわち、圧縮機1の
吐出口と蒸発器4の入口側とを結ぶ冷媒バイパス管12
が配設され、この冷媒バイパス管12に、例えば圧縮機
1の吸入側の冷媒圧力があらかじめ設定された設定圧力
になった時に開弁動作を開始する冷媒バイパス弁13が
設置されていることである。このように構成したこと
で、圧縮機1の吸入側圧力がこの設定圧力まで低下する
と、冷媒バイパス弁13は開弁動作を開始し、圧縮機1
が吐出する高温の冷媒ガスの一部を冷媒バイパス管12
を通して直接蒸発器4にバイパスさせて蒸発器4に模擬
負荷を与え、この状態で冷凍能力と冷凍負荷をバランス
させるようにする。これにより、図1に示した本発明の
一実施例の構成による動作に加えて、冷凍機のより幅広
い容量制御を可能にするものである。なお、この図3に
よる構成は、図2の本発明の異なる実施例の場合にも適
用できることは勿論である。FIG. 3 is a refrigerant circuit diagram of a refrigerator to which an embodiment of the present invention is applied. The difference from the embodiment of the present invention shown in FIG. 1 is that the embodiment of the present invention shown in FIG.
This is a combination of the techniques known in Japanese Patent No. 6853 that expand the capacity control range of a refrigerator. That is, the refrigerant bypass pipe 12 connecting the discharge port of the compressor 1 and the inlet side of the evaporator 4
The refrigerant bypass pipe 12 is provided with a refrigerant bypass valve 13 that starts a valve opening operation when the refrigerant pressure on the suction side of the compressor 1 reaches a preset set pressure. is there. With this configuration, when the suction side pressure of the compressor 1 drops to this set pressure, the refrigerant bypass valve 13 starts the valve opening operation, and the compressor 1
Part of the high-temperature refrigerant gas discharged by the refrigerant bypass pipe 12
The bypass is directly applied to the evaporator 4 to give a simulated load to the evaporator 4, and in this state, the refrigerating capacity and the refrigerating load are balanced. As a result, in addition to the operation of the configuration of the embodiment of the present invention shown in FIG. 1, a wider capacity control of the refrigerator can be performed. Of course, the configuration according to FIG. 3 can be applied to the case of a different embodiment of the present invention shown in FIG.
【0011】[0011]
【発明の効果】本発明においては、流量調整弁と並列に
冷媒の抵抗手段を備えたバイパス回路を配設すること
で、例えば何らかの原因で熱負荷が大幅に低下するなど
して、温度制御器からの信号により流量調整弁の弁開度
が全閉または全閉に近い状態に絞られることがあって
も、少量の冷媒の圧縮機への流入は維持されるので、圧
縮機の吸込圧力が負圧になることはなく、冷凍機は正常
な運転を継続することができ、かつこのことは、リミッ
タを保有していない汎用の温度制御器を採用しても達成
することができるので冷凍機を低コストとすることがで
きるという効果を奏する。According to the present invention, by disposing the bypass circuit having the resistance means for the refrigerant in parallel with the flow rate adjusting valve, for example, the thermal load is significantly reduced for some reason, and the temperature controller is controlled. Even if the valve opening of the flow rate adjustment valve is throttled to the fully closed state or a state close to the fully closed state by the signal from, the inflow of a small amount of refrigerant to the compressor is maintained. There is no negative pressure, the refrigerator can continue normal operation, and this can be achieved even by adopting a general-purpose temperature controller that does not have a limiter. It is possible to reduce the cost.
【図1】本発明の一実施例による冷凍機の冷媒回路図FIG. 1 is a refrigerant circuit diagram of a refrigerator according to an embodiment of the present invention.
【図2】本発明の異なる実施例による冷凍機の冷媒回路
図FIG. 2 is a refrigerant circuit diagram of a refrigerator according to another embodiment of the present invention.
【図3】本発明の一実施例を応用した冷凍機の冷媒回路
図FIG. 3 is a refrigerant circuit diagram of a refrigerator to which an embodiment of the present invention is applied.
【図4】従来技術による冷凍機の冷媒回路図FIG. 4 is a refrigerant circuit diagram of a refrigerator according to the related art.
1 圧縮機 1a 冷媒 2 凝縮器 3 膨張弁 4 蒸発器 5 流量調整弁 7 温度制御器 9 抵抗手段(キャピラリーチューブ) 10 バイパス流路 11 抵抗手段(手動調整弁) 1 Compressor 1a Refrigerant 2 Condenser 3 Expansion valve 4 Evaporator 5 Flow rate control valve 7 Temperature controller 9 Resistance means (capillary tube) 10 Bypass flow path 11 Resistance means (manual adjustment valve)
Claims (3)
発器と、この蒸発器で蒸発して低圧となった冷媒を吸入
口から吸い込み加圧圧縮して吐出口から吐出する圧縮機
と、この圧縮機で圧縮されて高温となった冷媒を冷却す
る凝縮器と、この凝縮器の下流に接続され前記圧縮機で
圧縮され高圧となった冷媒を膨張させる膨張弁と、前記
蒸発器と前記圧縮機の吸入口の間に挿入された前記冷媒
の流量を調整するための流量調整弁とを備えた冷凍機に
おいて、前記流量調整弁と並列に冷媒の抵抗手段を備え
たバイパス流路を配設したことを特徴とする冷凍機。1. An evaporator that produces cold heat by evaporating a refrigerant, and a compressor that sucks in and compresses a refrigerant that has been evaporated in this evaporator and has a low pressure through a suction port, and pressurizes and compresses it. A condenser that cools the high-temperature refrigerant that is compressed by the compressor, an expansion valve that is connected downstream of the condenser and that expands the high-pressure refrigerant that is compressed by the compressor, the evaporator, and the evaporator. In a refrigerator equipped with a flow rate adjusting valve for adjusting the flow rate of the refrigerant inserted between the suction ports of the compressor, a bypass flow path provided with a resistance means for the refrigerant is arranged in parallel with the flow rate adjusting valve. A refrigerator characterized by being installed.
段はキャピラリーチューブであることを特徴とする冷凍
機。2. The refrigerator according to claim 1, wherein the resistance means is a capillary tube.
段は手動調整弁であることを特徴とする冷凍機。3. The refrigerator according to claim 1, wherein the resistance means is a manual adjustment valve.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3209659A JPH0552430A (en) | 1991-08-22 | 1991-08-22 | Refrigerating machine |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3209659A JPH0552430A (en) | 1991-08-22 | 1991-08-22 | Refrigerating machine |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH0552430A true JPH0552430A (en) | 1993-03-02 |
Family
ID=16576475
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP3209659A Pending JPH0552430A (en) | 1991-08-22 | 1991-08-22 | Refrigerating machine |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH0552430A (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1800069A2 (en) * | 2004-08-20 | 2007-06-27 | Carrier Corporation | Compressor loading control |
CN102422099A (en) * | 2009-05-08 | 2012-04-18 | 三菱电机株式会社 | Air conditioner |
ITPD20130166A1 (en) * | 2013-06-11 | 2014-12-12 | Mta Spa | REFRIGERATION APPARATUS |
CN113390200A (en) * | 2020-12-23 | 2021-09-14 | 荏原冷热系统(中国)有限公司 | Coupled heat pump unit |
-
1991
- 1991-08-22 JP JP3209659A patent/JPH0552430A/en active Pending
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1800069A2 (en) * | 2004-08-20 | 2007-06-27 | Carrier Corporation | Compressor loading control |
EP1800069A4 (en) * | 2004-08-20 | 2010-10-13 | Carrier Corp | Compressor loading control |
CN102422099A (en) * | 2009-05-08 | 2012-04-18 | 三菱电机株式会社 | Air conditioner |
US8881548B2 (en) | 2009-05-08 | 2014-11-11 | Mitsubishi Electric Corporation | Air-conditioning apparatus |
ITPD20130166A1 (en) * | 2013-06-11 | 2014-12-12 | Mta Spa | REFRIGERATION APPARATUS |
WO2014199317A1 (en) * | 2013-06-11 | 2014-12-18 | M.T.A. S.P.A. | Refrigeration apparatus |
US10156371B2 (en) | 2013-06-11 | 2018-12-18 | M.T.A. S.P.A. | Refrigeration apparatus |
CN113390200A (en) * | 2020-12-23 | 2021-09-14 | 荏原冷热系统(中国)有限公司 | Coupled heat pump unit |
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