JPH0420754A - Freezer and method for adjusting its freezing capacity - Google Patents
Freezer and method for adjusting its freezing capacityInfo
- Publication number
- JPH0420754A JPH0420754A JP12491390A JP12491390A JPH0420754A JP H0420754 A JPH0420754 A JP H0420754A JP 12491390 A JP12491390 A JP 12491390A JP 12491390 A JP12491390 A JP 12491390A JP H0420754 A JPH0420754 A JP H0420754A
- Authority
- JP
- Japan
- Prior art keywords
- refrigerant
- compressor
- pressure
- cycle
- automatic
- 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.)
- Granted
Links
- 238000000034 method Methods 0.000 title claims abstract description 23
- 238000007710 freezing Methods 0.000 title abstract 3
- 230000008014 freezing Effects 0.000 title abstract 3
- 239000003507 refrigerant Substances 0.000 claims abstract description 101
- 230000006835 compression Effects 0.000 claims abstract description 16
- 238000007906 compression Methods 0.000 claims abstract description 16
- 238000001514 detection method Methods 0.000 claims description 18
- 238000001816 cooling Methods 0.000 abstract description 22
- 238000012545 processing Methods 0.000 abstract description 6
- 238000007599 discharging Methods 0.000 abstract 4
- 239000001307 helium Substances 0.000 description 24
- 229910052734 helium Inorganic materials 0.000 description 24
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 24
- 238000005057 refrigeration Methods 0.000 description 20
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 8
- 230000007423 decrease Effects 0.000 description 5
- 239000007789 gas Substances 0.000 description 5
- 229910052757 nitrogen Inorganic materials 0.000 description 4
- 238000012360 testing method Methods 0.000 description 4
- 239000002699 waste material Substances 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 238000009795 derivation Methods 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 238000011144 upstream manufacturing Methods 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Devices That Are Associated With Refrigeration Equipment (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、ブライトンサイクルまたはクロードサイクル
を使用した冷凍機及びその冷凍能力の調整方法に関し、
詳しくは冷凍サイクル内に膨張機、例えば膨張タービン
を備えた冷凍機において、その冷凍能力の調整を効率よ
く行うことのできる冷凍機及び冷凍サイクル内に膨張機
を備えた冷凍機の冷凍能力の調整を効率よく行う方法に
関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a refrigerator using a Brighton cycle or a Claude cycle, and a method for adjusting its refrigeration capacity.
In detail, in a refrigerator equipped with an expander, such as an expansion turbine, in the refrigeration cycle, the refrigeration capacity can be efficiently adjusted.The refrigeration capacity of a refrigerator equipped with an expander in the refrigeration cycle can be adjusted. Concerning how to do it efficiently.
温度を数に乃至数十Ｋに保つ極低温装置の冷却用として
、ヘリウムを冷媒としたブライトンサイクルからなる冷
凍機及びクロードサイクルからなる冷凍機が知られてい
る。前記ブライトンサイクルは、圧縮機で昇圧した冷媒
ガス（ヘリウム）を、必要に応じて液体窒素等の補助寒
冷と熱交換させた後に、膨張タービンで断熱膨張して寒
冷を発生した帰還冷媒ガスと熱交換させて冷却し、冷却
器、例えばクライオポンプにおけるクライオパネルに導
入して被冷却物を冷却するものである。冷却器導出後の
冷媒ガスは、帰還冷媒として膨張タービンに導入されて
断熱膨張し、寒冷を発生した後に前記昇圧後の冷媒ガス
の冷却源となり、前記圧縮機に帰還する。即ち、このブ
ライトンサイクルは、冷媒を圧縮する圧縮機と、圧縮後
の冷媒を帰還冷媒により冷却する熱交換器と、冷却後の
冷媒を導入して被冷却物の冷却を行う冷却器と、冷却器
導出後の冷媒を断熱膨張させる膨張機とを備え、該膨張
後の冷媒を前記帰還冷媒として前記熱交換器に導入し、
熱交換器導出後の帰還冷媒を前記圧縮機に帰還吸入させ
る冷凍サイクルから構成されている。2. Description of the Related Art Refrigerators based on a Brighton cycle and a freezer based on a Claude cycle using helium as a refrigerant are known for use in cooling cryogenic equipment that maintains temperatures at several to several tens of K. In the Brighton cycle, refrigerant gas (helium) pressurized by a compressor is exchanged with auxiliary refrigeration such as liquid nitrogen as necessary, and then adiabatically expanded in an expansion turbine to generate refrigeration and return refrigerant gas and heat. The coolant is exchanged and cooled, and then introduced into a cooler, for example, a cryopanel in a cryopump, to cool the object to be cooled. The refrigerant gas discharged from the cooler is introduced into the expansion turbine as a return refrigerant, undergoes adiabatic expansion, generates cold, and then becomes a cooling source for the pressurized refrigerant gas, returning to the compressor. In other words, this Brighton cycle consists of a compressor that compresses refrigerant, a heat exchanger that cools the compressed refrigerant with return refrigerant, a cooler that introduces the cooled refrigerant to cool the object to be cooled, and an expander that adiabatically expands the refrigerant after being discharged from the heat exchanger, and introducing the expanded refrigerant into the heat exchanger as the return refrigerant;
It consists of a refrigeration cycle in which the refrigerant returned from the heat exchanger is sucked back into the compressor.
尚、冷凍サイクル内における膨張機の位置は、被冷却物
を冷却する冷却器の後に設ける場合の他に、該冷却器の
前に設ける場合、冷却器の前と後の両方に設ける場合、
さらに冷却器の前に複数基設ける場合等、条件に応じて
種々である。また、冷凍サイクルは、前記ブライトンサ
イクルのみならず、サイクル系内にジュールトムソン（
Ｊ−Ｔ）弁を設けて断熱自由膨張による温度降下をも併
せて行うクロードサイクルも極低温発生用の冷凍機に用
いられている。The position of the expander in the refrigeration cycle is not only when it is installed after the cooler that cools the object to be cooled, but also when it is installed before the cooler, when it is installed both before and after the cooler.
Furthermore, there are various cases depending on the conditions, such as when multiple units are provided in front of the cooler. In addition, the refrigeration cycle includes not only the Brighton cycle but also the Joule-Thomson (
J-T) The Claude cycle, which also includes a valve and lowers the temperature by adiabatic free expansion, is also used in refrigerators for generating cryogenic temperatures.
一方、極低温に保持された定常運転時における熱損失が
極小となるように設計されている極低温装置においては
、定常時の冷却能力はそれほど必要としないが、該装置
を所定の極低温まで冷却する予冷時の冷却能力は、予冷
時間の短縮の観点からできるだけ大きいものが要求され
、著しい場合には、予冷時冷却能力が定常時冷却能力の
２倍以上の冷凍機を必要としていた。そのため極低温装
置に用いる冷凍機では、該極低温装置を所定温度まで冷
却するための予冷時の冷却能力を目標として設計する必
要があった。On the other hand, cryogenic equipment that is designed to minimize heat loss during steady-state operation maintained at a cryogenic temperature does not require much cooling capacity during steady-state operation; The cooling capacity during precooling is required to be as large as possible from the viewpoint of shortening the precooling time, and in severe cases, a refrigerator whose cooling capacity during precooling is twice or more than the steady state cooling capacity is required. Therefore, it is necessary to design a refrigerator used in a cryogenic device with a target cooling capacity during precooling to cool the cryogenic device to a predetermined temperature.
従って、極低温装置の定常運転時に余剰となる冷凍機の
冷凍能力を調整する必要があるが、従来は以下に示す方
法により行われていた。Therefore, it is necessary to adjust the surplus refrigerating capacity of the refrigerator during steady operation of the cryogenic apparatus, but this has conventionally been done by the method described below.
（１）冷凍機に付設した内部ヒーターにより余剰寒冷分
を消費する。(1) Excess cold water is consumed by an internal heater attached to the refrigerator.
（２）膨張タービン人口弁の開度を絞って寒冷発生量を
減少させる。(2) Reduce the amount of cold generation by narrowing the opening of the expansion turbine artificial valve.
（３）液化窒素等の補助寒冷量を絞って寒冷発生量を減
少させる。(3) Reduce the amount of cold generated by reducing the amount of supplementary cold such as liquefied nitrogen.
（４）圧縮機の吐出圧力を下げて膨張タービンの膨張比
を下げる。(4) Lower the discharge pressure of the compressor to lower the expansion ratio of the expansion turbine.
（５）圧縮機の内部バイパス等による風量調整により冷
媒流量を減少させる。(5) Reduce the refrigerant flow rate by adjusting the air volume using an internal bypass of the compressor, etc.
しかしながら、上述の（１）〜（３）の方法では、圧縮
機の運転状態が予冷時と定常時とて同一であるため、圧
縮機動力は余剰冷凍能力分浪費されることになる。また
、上記（４）の方法では、膨張タビンの膨張比あるいは
膨張タービンの出入口の温度が予冷時と定常時とで異な
るため、膨張タービンを最適設計点で運転することがで
きず、効率が低下して圧縮機動力に無駄を生じることに
なる。However, in the methods (1) to (3) described above, since the operating state of the compressor is the same during precooling and during steady state, the compressor power is wasted by the excess refrigerating capacity. In addition, in method (4) above, the expansion ratio of the expansion turbine or the temperature at the entrance and exit of the expansion turbine differs between precooling and steady state, making it impossible to operate the expansion turbine at the optimal design point, resulting in a decrease in efficiency. This results in wasted compressor power.
また、上記（５）の方法においても、膨張タービンの特
性により、圧縮機の吐出圧力が一定のままであれば、該
膨張タービンにおける風量が一定となるため、該風量を
減少させるためには膨張タービンの入口圧力を下げざる
を得ず、前記（４）の方法と同様に効率が低下し、動力
の浪費となる。Also, in the method (5) above, due to the characteristics of the expansion turbine, if the discharge pressure of the compressor remains constant, the air volume in the expansion turbine remains constant. The inlet pressure of the turbine has to be lowered, resulting in a decrease in efficiency and a waste of power, similar to the method (4) above.
また、一方では、従来の極低温装置が比較的小型の実験
装置であり、定常時の運転時間も比較的短かったため、
上記のような圧縮機動力費の浪費もそれほど問題とされ
ていなかったが、人工衛星やその他の設備を宇宙環境下
で試験するための試験設備（スペースチェンバ）では、
試験体を収容する空間が大きくなるとともに、その試験
時間も長くなるため、上記定常時の動力費の浪費も大き
な問題となる。On the other hand, conventional cryogenic equipment was relatively small experimental equipment, and the operating time in steady state was relatively short.
The waste of compressor power costs as mentioned above was not considered to be much of a problem, but in test facilities (space chambers) for testing artificial satellites and other equipment in the space environment,
As the space for accommodating the test specimen becomes larger, the test time also becomes longer, and the waste of power costs during the steady state becomes a major problem.
また、ガスの液化装置等において、例えば２基の液化装
置に対して１基の冷凍機を配設した場合は、１基の液化
装置の運転停止時には冷凍機の必要冷凍能力が半分とな
るが、従来は上記同様に冷凍能力を調整していたため、
同様の動力費の無駄を生じていた。In addition, in a gas liquefaction device, for example, if one refrigerator is installed for two liquefaction devices, the required refrigerating capacity of the refrigerator will be halved when one liquefaction device stops operating. , Previously, the refrigeration capacity was adjusted in the same way as above,
This resulted in a similar waste of power costs.
そこで、本発明は、冷凍機の最大の冷凍能力を効率よく
得られるとともに、冷凍能力の調整も動力費の無駄を生
じることなく効率よく行うことのできる冷凍機及びその
冷凍能力の調整方法を提供することを目的としている。SUMMARY OF THE INVENTION Therefore, the present invention provides a refrigerator and a method for adjusting its cooling capacity, which can efficiently obtain the maximum refrigerating capacity of the refrigerator and also adjust the refrigerating capacity efficiently without wasting power costs. It is intended to.
〔課題を解決するための手段〕
上記した目的を達成するために、本発明の冷凍機は、第
１の構成として、ブライトンサイクルまたはクロードサ
イクルを使用した冷凍機において、該サイクル内の冷媒
量を制御するとともに、該サイクル内に設けた冷媒用圧
縮機の圧縮比を一定もしくは略一定に保った状態で圧力
レベルを変更し得る圧縮機の吸入圧力、吐出圧力制御手
段を設けたことを特徴とし、第２の構成として、冷媒用
タンクを設けるとともに、冷媒用圧縮機の冷媒導入経路
及び冷媒導出経路を、それぞれ冷媒自動導入弁及び冷媒
自動導出弁を介して前記冷媒用タンクに接続し、かつ前
記冷媒導入経路と冷媒導出経路とを結ぶバイパス経路を
自動バイパス弁を介して設け、前記冷媒用圧縮機の吐出
圧力を検出し、該検出圧力により前記冷媒自動導入弁及
び冷媒自動導出弁を制御する冷媒用圧縮機吐出圧力検出
制御設定器と、該冷媒用圧縮機の吸入圧力を検出し、該
検出圧力により前記自動バイパス弁を制御する冷媒用圧
縮機吸入圧力検出制御設定器とを設け、該冷媒用圧縮機
吐出圧力検出制御設定器と冷媒用圧縮機吸入圧力検出制
御設定器とを連動させるカスケード制御器を設けたこと
を特徴としている。[Means for Solving the Problems] In order to achieve the above-mentioned object, the refrigerator of the present invention has a first configuration in which, in a refrigerator using a Brighton cycle or a Claude cycle, the amount of refrigerant in the cycle is reduced. In addition to controlling the refrigerant compressor provided in the cycle, the refrigerant compressor is characterized by being provided with suction pressure and discharge pressure control means that can change the pressure level while keeping the compression ratio of the refrigerant compressor constant or substantially constant. , as a second configuration, a refrigerant tank is provided, and a refrigerant introduction route and a refrigerant outlet route of the refrigerant compressor are connected to the refrigerant tank via an automatic refrigerant introduction valve and an automatic refrigerant discharge valve, respectively, and A bypass path connecting the refrigerant introduction route and the refrigerant outlet route is provided via an automatic bypass valve, the discharge pressure of the refrigerant compressor is detected, and the detected pressure controls the automatic refrigerant introduction valve and the automatic refrigerant outlet valve. a refrigerant compressor discharge pressure detection control setting device, and a refrigerant compressor suction pressure detection control setting device that detects the suction pressure of the refrigerant compressor and controls the automatic bypass valve based on the detected pressure, The present invention is characterized by providing a cascade controller that interlocks the refrigerant compressor discharge pressure detection control setting device and the refrigerant compressor suction pressure detection control setting device.
また、本発明の冷凍機の冷凍能力の調整方法は、第１の
構成として、ブライトンサイクルまたはクロードサイク
ルを使用した冷凍機の冷凍能力を調整する方法において
、該サイクル内の冷媒用圧縮機の冷媒導出経路に設けた
冷媒自動導出弁と、該圧縮機の冷媒導入経路に設けた冷
媒自動導入弁とにより冷媒吐出圧力を制御するとともに
、冷媒導出経路と冷媒導入経路とを結ぶバイパス経路に
設けた自動バイパス弁により、前記冷媒用圧縮機の冷媒
吸入圧力を制御し、前配圧縮機の圧縮比を略一定に維持
しつつ圧力レベルを変更することを特徴とし、第２の構
成として、被冷却物または冷却器出口の温度を検出し、
該検出温度により冷媒用圧縮機における冷媒循環量を調
節し、該冷凍機の寒冷発生量を調節することを特徴とし
、第３の構成として、被冷却物または冷却器出口の温度
を検出し、該検出温度により冷媒用圧縮機の圧縮比を略
一定に維持しつつ圧力レベルを変更し、該冷凍機の寒冷
発生量を調節することを特徴としている。The method for adjusting the refrigerating capacity of a refrigerating machine of the present invention includes, as a first configuration, a method for adjusting the refrigerating capacity of a refrigerating machine using a Brighton cycle or a Claude cycle. The refrigerant discharge pressure is controlled by an automatic refrigerant discharge valve provided in the derivation path and an automatic refrigerant introduction valve provided in the refrigerant introduction path of the compressor, and an automatic refrigerant introduction valve provided in the bypass path connecting the refrigerant derivation path and the refrigerant introduction path. The refrigerant suction pressure of the refrigerant compressor is controlled by an automatic bypass valve, and the pressure level is changed while maintaining the compression ratio of the upstream compressor approximately constant. Detects the temperature of the object or cooler outlet,
The refrigerant circulation amount in the refrigerant compressor is adjusted based on the detected temperature, and the amount of cold generated by the refrigerator is adjusted.As a third configuration, the temperature of the object to be cooled or the outlet of the cooler is detected, It is characterized in that the detected temperature changes the pressure level while keeping the compression ratio of the refrigerant compressor substantially constant, and adjusts the amount of cold generated by the refrigerator.
上記のように、圧縮機の吸入圧力と吐出圧力の比を同一
もしくは路間−とすることにより、膨張機（膨張タービ
ン等）における膨張比も同一もしくは路間−にてき、膨
張機の効率低下を避けることができる。また、圧力レベ
ルを下げることにより圧縮機の動力費を低減できる。As mentioned above, by making the ratio of the suction pressure and discharge pressure of the compressor the same or between the passages, the expansion ratio in the expander (expansion turbine, etc.) will also be the same or between the passages, reducing the efficiency of the expander. can be avoided. Furthermore, by lowering the pressure level, the power cost of the compressor can be reduced.
以下、本発明を図面に示す実施例に基づいて、さらに詳
細に説明する。Hereinafter, the present invention will be explained in more detail based on embodiments shown in the drawings.
第１図は本発明を適用したブライトンサイクル冷凍機の
一実施例を示している。この冷凍機１は、極低温及び高
真空を得るためのもので、圧縮比を一定もしくは略一定
に保った状態で圧力レベルを変えることのできる型式の
圧縮機２と、液体窒素タンク３からの液体窒素等の補助
寒冷及び帰還ヘリウムにより、前記昇圧後のヘリウムを
冷却する第１熱交換器４と、該ヘリウムを帰還ヘリウム
により所定温度にまで冷却する第２熱交換器５と、該第
２熱交換器５で冷却された極低温のヘリウムを導入して
被冷却物Ａの冷却と同時に、例えばスペースチェンバー
等において高真空を形成するクライオパネル等の冷却器
６と、該冷却器６を導出した後のヘリウムを断熱膨張さ
せる膨張タービン７と、該膨張タービン７の前段に配設
された内部ヒーター８とを備えた冷凍サイクルからなる
主回路９と、ヘリウムタンク１０及び該ヘリウムタンク
１０から前記圧縮機２の両日にそれぞれ接続されたヘリ
ウム導入経路１１とヘリウム導出経路１２と、この両経
路１１．１２中に設けられた冷媒自動導入弁１１ａ及び
冷媒自動導出弁１２ａと吐出圧力検出制御設定器１３と
を有する吐出圧力制御手段（冷媒量制御手段）１４と、
必要な冷却能力に応じて設定され、圧縮機２の吸入圧力
を制御する自動バイパス弁１５ａを有するバイパス経路
１５、及び吸入圧力を検出し、設定値に応じて制御する
吸入圧力検出制御設定器１６からなる吸入圧力制御手段
１７と、起動、停止時のためのタービン人口弁１８と、
そしてこれらを統一制御するカスケード制御器１９とか
ら構成されている。FIG. 1 shows an embodiment of a Brighton cycle refrigerator to which the present invention is applied. This refrigerator 1 is used to obtain extremely low temperatures and high vacuum, and includes a compressor 2 that can change the pressure level while keeping the compression ratio constant or almost constant, and a compressor 2 that can change the pressure level while keeping the compression ratio constant or almost constant. A first heat exchanger 4 that cools the pressurized helium using auxiliary cooling such as liquid nitrogen and returned helium; a second heat exchanger 5 that cools the helium to a predetermined temperature using returned helium; At the same time as cooling the object A by introducing cryogenic helium cooled by the heat exchanger 5, a cooler 6 such as a cryopanel that forms a high vacuum in, for example, a space chamber, and the cooler 6 are introduced. A main circuit 9 includes a refrigeration cycle including an expansion turbine 7 that adiabatically expands the helium after heating, an internal heater 8 disposed upstream of the expansion turbine 7, a helium tank 10, and a helium tank 10. A helium introduction path 11 and a helium extraction path 12 connected to both sides of the compressor 2, an automatic refrigerant introduction valve 11a and an automatic refrigerant extraction valve 12a provided in both paths 11 and 12, and a discharge pressure detection control setting device. 13, a discharge pressure control means (refrigerant amount control means) 14,
A bypass path 15 having an automatic bypass valve 15a that is set according to the required cooling capacity and controls the suction pressure of the compressor 2, and a suction pressure detection control setting device 16 that detects the suction pressure and controls it according to the set value. a suction pressure control means 17 consisting of; a turbine artificial valve 18 for starting and stopping;
It also includes a cascade controller 19 that controls these in a unified manner.
この冷凍機１において、まず被冷却物Ａを常温から冷却
（予冷）する時には、吐出圧力検出制御設定器１３及び
吸入圧力検出制御設定器１６の設定値を可能な限り上げ
て膨張タービン７の最大処理運転を行う。そして被冷却
物Ａが最終冷却温度に達した後は、定常時の被冷却物Ａ
の減少熱負荷に合わせて吐出圧力検出制御設定器１３の
設定値を下げると同時に、前記予冷時の圧縮機吐出圧力
と吸入圧力との設定値比率（圧縮比）を一定に保つよう
に吸入圧力検出制御設定器１６の設定値も下げる。In this refrigerator 1, when cooling (precooling) the object to be cooled A from room temperature, the setting values of the discharge pressure detection control setting device 13 and the suction pressure detection control setting device 16 are raised as much as possible to maximize the expansion turbine 7. Perform processing operation. After the cooled object A reaches the final cooling temperature, the cooled object A during steady state is
At the same time, the setting value of the discharge pressure detection control setting device 13 is lowered in accordance with the decreasing heat load of The setting value of the detection control setting device 16 is also lowered.
一般に、膨張タービン処理量は、膨張タービン入口温度
が一定の場合には、膨張タービン入口圧力、即ち圧縮機
吐出圧力に比例するとともに、圧縮機処理風量は、吸入
圧力に比例する。従って、圧縮機２の圧縮比を一定とす
れば、吸入圧力減少時の圧縮機処理風量と吐出圧力減少
時の膨張タビン処理量とを合致させることが可能であり
、定常時の必要冷凍負荷減少時も、それに応した圧縮機
動力及び寒冷を得ることができる。Generally, when the expansion turbine inlet temperature is constant, the expansion turbine throughput is proportional to the expansion turbine inlet pressure, that is, the compressor discharge pressure, and the compressor throughput is proportional to the suction pressure. Therefore, if the compression ratio of the compressor 2 is kept constant, it is possible to match the compressor processing air volume when the suction pressure decreases and the expansion turbine processing volume when the discharge pressure decreases, which reduces the required refrigeration load during steady state. The compressor power and refrigeration can be obtained accordingly.
即ち、予冷時にはヘリウム導入回路１１の弁１１ａが開
となり、主回路９内にタンク１０よりヘリウムを導入し
て吐出圧力を上げ、該主回路９の圧力レベルを上げるこ
とにより、主回路９内を流れるヘリウム量を可能な限り
増量し、圧縮機２や膨張タービン７、その他の設備の最
大能力での運転を行い、該冷凍機１における冷却能力を
最大に引出して予冷時間の短縮を図る。この時、吸入圧
力検出制御設定器１６により自動バイパス弁１５ａの開
度をＪｉｌ！ｒ１シて圧縮機２における圧縮比を一定に
保つように吸入圧力を調節する。That is, during precooling, the valve 11a of the helium introduction circuit 11 is opened, helium is introduced into the main circuit 9 from the tank 10 to increase the discharge pressure, and by raising the pressure level of the main circuit 9, the inside of the main circuit 9 is The amount of flowing helium is increased as much as possible, the compressor 2, the expansion turbine 7, and other equipment are operated at their maximum capacity, and the cooling capacity of the refrigerator 1 is maximized to shorten the precooling time. At this time, the opening degree of the automatic bypass valve 15a is set to Jil! by the suction pressure detection control setting device 16. The suction pressure is adjusted so as to keep the compression ratio in the compressor 2 constant.
そして定常時には、冷媒導入自動弁１１ａを閉とし、ヘ
リウム導出回路１２の冷媒導出自動弁１２ａを開いて主
回路９内を流れるヘリウムをヘリウムタンク１０に回収
し、該主回路９内のヘリウム量を減らして吐出圧力を下
げる。この時、吸入圧力検出制御設定器１６により自動
バイパス弁１５ａの開度を調節して圧縮機２における圧
縮比を一定に保つように吸入圧力を下げながら主回路９
の圧力レベルを下げることにより、圧縮機吐出圧力に依
存する膨張タービン入口圧力と、圧縮機吸入圧力に依存
する膨張タービン出口圧力との比（膨張比）を略一定に
保つことができ、該膨張タビン７の能力を最大に生かし
た運転を続けることができる。During normal operation, the automatic refrigerant inlet valve 11a is closed, the automatic refrigerant outlet valve 12a of the helium outlet circuit 12 is opened, and the helium flowing in the main circuit 9 is collected into the helium tank 10, and the amount of helium in the main circuit 9 is reduced. Reduce the discharge pressure. At this time, the suction pressure detection control setting device 16 adjusts the opening degree of the automatic bypass valve 15a to keep the compression ratio in the compressor 2 constant while lowering the suction pressure in the main circuit 9.
By lowering the pressure level of the expansion turbine, the ratio (expansion ratio) between the expansion turbine inlet pressure, which depends on the compressor discharge pressure, and the expansion turbine outlet pressure, which depends on the compressor suction pressure, can be kept approximately constant. It is possible to continue operating the Tabin 7 by making the most of its capabilities.
また、圧縮比を一定もしくは略一定に保った状態で圧力
レベルを変えることのできる型式の圧縮機２として、例
えばスクリュー式、ルーツ式、可動翼式、往復動式等の
体積型圧縮機を用いることにより、予冷時と定常時のヘ
リウム流量（風量）の差を、圧縮機吸入圧力を制御する
ことにより調整できる。これにより、圧縮機本体は、予
冷時の吸入圧力が高くなるので、予冷時、定常時共に同
一サイズでよくなり、従来法のように予冷時の冷凍能力
を満足させるために大きなサイズの圧縮機を選定する必
要がなくなる。In addition, as the type of compressor 2 that can change the pressure level while keeping the compression ratio constant or approximately constant, for example, a positive displacement compressor such as a screw type, Roots type, movable blade type, or reciprocating type is used. As a result, the difference in helium flow rate (air volume) during precooling and during steady state can be adjusted by controlling the compressor suction pressure. This increases the suction pressure during precooling, so the compressor body can be of the same size for both precooling and steady state operations. There is no need to select.
また、内部ヒーター８は、定常時の冷凍能力の微調整用
として用いるものであり、補助寒冷量の調整弁３ａも同
様に補助調整用として設けられている。従ってこれらの
内部ヒーター８や補助寒冷剤を省略しても本発明の冷凍
機を構成することができ、本発明方法を実施することは
可能である。Further, the internal heater 8 is used for fine adjustment of the refrigeration capacity during steady state, and the auxiliary cooling amount adjustment valve 3a is also provided for auxiliary adjustment. Therefore, even if the internal heater 8 and the auxiliary cryogen are omitted, the refrigerator of the present invention can be constructed and the method of the present invention can be practiced.
また、前述の吸入圧力検出制御設定器１６．吐出圧力検
出制御設定器１３．冷却器導出後のヘリウム温度を測定
する温度計２０等をカスケード制御器１９と連結し、該
温度計２０の検出温度または被冷却物Ａの温度によって
系全体をカスケード制御することにより、予冷から定常
運転までの全自動運転が可能である。In addition, the above-mentioned suction pressure detection control setting device 16. Discharge pressure detection control setting device 13. By connecting a thermometer 20 etc. that measures the helium temperature after being led out of the cooler to the cascade controller 19, and controlling the entire system in cascade based on the temperature detected by the thermometer 20 or the temperature of the object to be cooled A, it is possible to change the temperature from pre-cooling to steady state. Fully automatic operation is possible up to the point of operation.
次に実験例を説明する。Next, an experimental example will be explained.
上記第１図と同様の構成の冷凍機を、窒素を２０に以下
で凝縮させてスペースチェンバ内を高真空度とするため
のクライオパネル冷却用冷凍機に用いた。予冷時と定常
時の冷凍機の状態を第１表に示す。A refrigerator having a configuration similar to that shown in FIG. 1 above was used as a refrigerator for cooling a cryopanel for condensing nitrogen to 20 ml or less to create a high degree of vacuum in a space chamber. Table 1 shows the conditions of the refrigerator during precooling and steady state.
次に、第２図に基づいて、本発明をクロードサイクルを
使用した冷凍機３０に適用した一実施例を説明する。Next, an embodiment in which the present invention is applied to a refrigerator 30 using a Claude cycle will be described based on FIG.
上記クロードサイクルの基本構成は、極低温発生部にＪ
−Ｔ膨張弁３１が設けられていて、該膨張弁３１による
冷媒のＪ−Ｔ膨張によって膨張タービンの出口温度より
もさらに低い温度まで、即ち冷媒の液化領域の低温まで
の極低温を得るようにした点が異なるのみで、他は前記
ブライトンサイクルと路間−である。従って、本実施例
における冷凍能力の調整方法も、前記ブライトンサイク
ルを使用した冷凍機の冷凍能力の調整方法と同様であり
、装置構成も上記冷凍サイクルの基本構成の相違部分を
除き、他は同一に構成できる。The basic configuration of the above Claude cycle is that J
- a T-expansion valve 31 is provided so that the J-T expansion of the refrigerant by said expansion valve 31 obtains a cryogenic temperature even lower than the outlet temperature of the expansion turbine, i.e. to the low temperature of the liquefaction region of the refrigerant; The only difference is that this is the same as the Brighton cycle. Therefore, the method for adjusting the refrigerating capacity in this example is the same as the method for adjusting the refrigerating capacity of the refrigerator using the Brighton cycle, and the device configuration is the same except for the difference in the basic configuration of the refrigerating cycle. It can be configured as follows.
第２図において、冷媒用圧縮機２よりカスケード制御器
１９まては、前記ブライトンサイクル冷凍機の場合と同
様であるため、対応部分に同一符号を付してその詳細な
説明は省略する。膨張タービン３２に導入する冷媒ヘリ
ウムは、主回路９の途中から分岐して分岐流３３を形成
し、膨張タービン３２て膨張して発生した寒冷は、ター
ビン熱交換器３４で主流れ３５を冷却して帰還流となる
。In FIG. 2, the components from the refrigerant compressor 2 to the cascade controller 19 are the same as those of the Brighton cycle refrigerator, so corresponding parts are given the same reference numerals and detailed explanation thereof will be omitted. The refrigerant helium introduced into the expansion turbine 32 branches from the middle of the main circuit 9 to form a branched flow 33 , and the cold generated by expansion in the expansion turbine 32 cools the main flow 35 in the turbine heat exchanger 34 . It becomes a return flow.
冷媒ヘリウムの主流れ３５は、さらにＪ−Ｔ熱交換器３
６てＪ−Ｔ膨張後冷却器６から帰還する帰還冷媒ヘリウ
ムと熱交換して降温した後、Ｊ−Ｔ膨張弁３１で膨張降
温して冷却器６に入り、被冷却物を冷却し、前記Ｊ−Ｔ
熱交換器３６．タービン熱交換器３４．第２熱交換器５
．第１熱交換器４を経て圧縮機２へ帰還する。また、図
中、３７は冷却器の温度を検出する温度計、３８．３９
は起動時の予冷用バイパス回路、３８ａ、３９ａは予冷
用バイパス弁、４０は流量調節弁である。The main flow 35 of refrigerant helium is further passed through the J-T heat exchanger 3
After the J-T expansion, the temperature is lowered by exchanging heat with the return refrigerant helium that returns from the cooler 6, and then expanded by the J-T expansion valve 31 to lower the temperature and enter the cooler 6 to cool the object to be cooled. J-T
Heat exchanger 36. Turbine heat exchanger 34. Second heat exchanger 5
．． It returns to the compressor 2 via the first heat exchanger 4. In addition, in the figure, 37 is a thermometer that detects the temperature of the cooler, 38.39
38a and 39a are pre-cooling bypass valves, and 40 is a flow control valve.
また、第３図は、前記冷却器がクライオパネルや熱交換
器ではなく、槽または容器４０内の被冷却物４１が冷媒
液中に浸漬状態にある場合を示している。この場合は、
例えば超電導マグネットの冷却等の場合であって、容器
４０内は略大気圧付近であり、主回路９内の冷媒は経路
９ａから導入され、経路９ｂから帰還する。また４２は
被冷却物４１の温度を検出する温度計である。Further, FIG. 3 shows a case where the cooler is not a cryopanel or a heat exchanger, and the object 41 to be cooled in the tank or container 40 is immersed in the refrigerant liquid. in this case,
For example, in the case of cooling a superconducting magnet, the inside of the container 40 is at approximately atmospheric pressure, and the refrigerant in the main circuit 9 is introduced through the path 9a and returned through the path 9b. Further, 42 is a thermometer that detects the temperature of the object 41 to be cooled.
このような構成のクロードサイクル冷凍機においても、
前記第１図に示したブライトンサイクル冷凍機と同様に
して冷凍能力を調整することができ、同様の効果を得る
ことができる。Even in a Claude cycle refrigerator with such a configuration,
Refrigeration capacity can be adjusted in the same manner as the Brighton cycle refrigerator shown in FIG. 1, and similar effects can be obtained.
以上説明したように、本発明によれば、冷凍サイクル内
に膨張機を備えた冷凍機における圧縮機の圧縮比を、一
定乃至略一定に保ちながらサイクル内の圧力レベルを制
御して冷凍サイクル内の冷媒量を調整し、これによって
冷凍機冷凍能力の調整を行うようにしたので、冷凍能力
を変化させても膨張機の膨張比を略一定に維持すること
ができ、膨張機を最も好ましい状態で運転できる。これ
により効率よく寒冷を発生させることができ、寒冷損失
の低減を図れるとともに、必要寒冷減少時は、圧縮機の
圧力レベルを下げることにより圧縮機の動力費の低減も
図れる。As explained above, according to the present invention, the compression ratio of the compressor in a refrigerator equipped with an expander in the refrigeration cycle is kept constant or substantially constant, and the pressure level in the cycle is controlled. The amount of refrigerant in the refrigerator is adjusted, and the refrigerating capacity of the refrigerator is adjusted accordingly, so even if the refrigerating capacity is changed, the expansion ratio of the expander can be maintained approximately constant, and the expander can be kept in the most favorable state. I can drive. This makes it possible to efficiently generate refrigeration, reduce refrigeration loss, and reduce compressor power costs by lowering the pressure level of the compressor when the required refrigeration decreases.
また、上記機能を備えた冷凍機において、各部の弁に自
動弁、圧力検出制御設定器を用いて上記操作を自動制御
とし、ざらにカスケード制御器を用いて冷却器出口温度
または被冷却物温度を検出し、これによってカスケード
制御を行い、全自動運転とすることができる。In addition, in a refrigerator equipped with the above functions, the above operations are automatically controlled using automatic valves and pressure detection control settings for each part, and a cascade controller is used to control the temperature of the cooler outlet temperature or the temperature of the cooled object. This enables cascade control and fully automatic operation.
また、圧縮機本体も、予冷時吸入圧力を高くすることて
、従来法に用いるものより大きなサイズのものを選定す
る必要がない。Furthermore, by increasing the suction pressure during precooling, there is no need to select a compressor body larger than that used in the conventional method.
【図面の簡単な説明】
第１図は本発明を適用したブライトンサイクル冷凍機の
一実施例を示す系統図、第２図は本発明を適用したクロ
ードサイクル冷凍機の一実施例を示す系統図、第３図は
被冷却物の他の実施例を示す説明図である。[Brief Description of the Drawings] Fig. 1 is a system diagram showing an embodiment of a Brighton cycle refrigerator to which the present invention is applied, and Fig. 2 is a system diagram showing an embodiment of a Claude cycle refrigerator to which the present invention is applied. , FIG. 3 is an explanatory diagram showing another embodiment of the object to be cooled.
Claims (1)
した冷凍機において、該サイクル内の冷媒量を制御する
とともに、該サイクル内に設けた冷媒用圧縮機の圧縮比
を一定もしくは略一定に保った状態で圧力レベルを変更
し得る圧縮機の吸入圧力、吐出圧力制御手段を設けたこ
とを特徴とする冷凍機。 ２、ブライトンサイクルまたはクロードサイクルを使用
した冷凍機において、冷媒用タンクを設けるとともに、
冷媒用圧縮機の冷媒導入経路及び冷媒導出経路を、それ
ぞれ冷媒自動導入弁及び冷媒自動導出弁を介して前記冷
媒用タンクに接続し、かつ前記冷媒導入経路と冷媒導出
経路とを結ぶバイパス経路を自動バイパス弁を介して設
け、前記冷媒用圧縮機の吐出圧力を検出し、該検出圧力
により前記冷媒自動導入弁及び冷媒自動導出弁を制御す
る冷媒用圧縮機吐出圧力検出制御設定器と、該冷媒用圧
縮機の吸入圧力を検出し、該検出圧力により前記自動バ
イパス弁を制御する冷媒用圧縮機吸入圧力検出制御設定
器とを設け、該冷媒用圧縮機吐出圧力検出制御設定器と
冷媒用圧縮機吸入圧力検出制御設定器とを連動させるカ
スケード制御器を設けたことを特徴とする冷凍機。 ３、前記冷媒用圧縮機が体積型圧縮機であることを特徴
とする請求項１または２記載の冷凍機。 ４、ブライトンサイクルまたはクロードサイクルを使用
した冷凍機の冷凍能力を調整する方法において、該サイ
クル内の冷媒用圧縮機の冷媒導出経路に設けた冷媒自動
導出弁と、該圧縮機の冷媒導入経路に設けた冷媒自動導
入弁とにより冷媒吐出圧力を制御するとともに、冷媒導
出経路と冷媒導入経路とを結ぶバイパス経路に設けた自
動バイパス弁により、前記冷媒用圧縮機の冷媒吸入圧力
を制御し、前記圧縮機の圧縮比を略一定に維持しつつ圧
力レベルを変更することを特徴とする冷凍機の冷凍能力
の調整方法。 ５、前記冷媒自動導出弁及び冷媒自動導入弁の調節を、
冷媒圧縮機吐出圧力を検出して、この検出圧力により行
い、かつ自動バイパス弁の制御を、冷媒用圧縮機の吸入
圧力を検出して、この検出圧力により行うことにより、
前記冷媒用圧縮機における冷媒循環量を制御して、該圧
縮機の圧縮比を略一定に維持しつつ圧力レベルを変更す
ることを特徴とする請求項４記載の冷凍機の冷凍能力の
調整方法。 ６、ブライトンサイクルまたはクロードサイクルを使用
した冷凍機の冷凍能力を調整する方法において、被冷却
物または冷却器出口の温度を検出し、該検出温度により
冷媒用圧縮機における冷媒循環量を調節し、該冷凍機の
寒冷発生量を調節することを特徴とする冷凍機の冷凍能
力の調整方法。 ７、ブライトンサイクルまたはクロードサイクルを使用
した冷凍機の冷凍能力を調整する方法において、被冷却
物または冷却器出口の温度を検出し、該検出温度により
冷媒用圧縮機の圧縮比を略一定に維持しつつ圧力レベル
を変更し、該冷凍機の寒冷発生量を調節することを特徴
とする冷凍機の冷凍能力の調整方法。 ８、前記冷媒用圧縮機が体積型圧縮機であることを特徴
とする請求項４乃至７いずれかに記載の冷凍機の冷凍能
力の調整方法。[Claims] 1. In a refrigerator using a Brighton cycle or a Claude cycle, the amount of refrigerant in the cycle is controlled, and the compression ratio of a refrigerant compressor provided in the cycle is kept constant or approximately constant. A refrigerating machine characterized by being provided with means for controlling suction pressure and discharge pressure of a compressor, which can change the pressure level while maintaining the same pressure level. 2. In a refrigerator using the Brighton cycle or Claude cycle, a refrigerant tank is provided, and
A refrigerant introduction route and a refrigerant outlet route of the refrigerant compressor are connected to the refrigerant tank via an automatic refrigerant introduction valve and an automatic refrigerant outlet valve, respectively, and a bypass route connecting the refrigerant introduction route and the refrigerant outlet route is provided. a refrigerant compressor discharge pressure detection control setting device that is provided via an automatic bypass valve, detects the discharge pressure of the refrigerant compressor, and controls the automatic refrigerant introduction valve and the automatic refrigerant discharge valve based on the detected pressure; a refrigerant compressor suction pressure detection control setting device that detects the suction pressure of the refrigerant compressor and controls the automatic bypass valve based on the detected pressure; A refrigerator characterized by being provided with a cascade controller that interlocks with a compressor suction pressure detection control setting device. 3. The refrigerator according to claim 1 or 2, wherein the refrigerant compressor is a volumetric compressor. 4. In a method for adjusting the refrigerating capacity of a refrigerator using a Brighton cycle or a Claude cycle, an automatic refrigerant discharge valve provided in a refrigerant discharge path of a refrigerant compressor in the cycle and a refrigerant introduction path of the compressor are provided. The refrigerant discharge pressure is controlled by the provided automatic refrigerant introduction valve, and the refrigerant suction pressure of the refrigerant compressor is controlled by the automatic bypass valve provided in the bypass path connecting the refrigerant outlet path and the refrigerant introduction path. A method for adjusting the refrigerating capacity of a refrigerating machine, characterized by changing the pressure level while maintaining the compression ratio of the compressor substantially constant. 5. Adjustment of the automatic refrigerant discharge valve and automatic refrigerant introduction valve,
By detecting the refrigerant compressor discharge pressure and controlling the automatic bypass valve using the detected pressure, detecting the suction pressure of the refrigerant compressor and controlling the automatic bypass valve using the detected pressure.
5. The method for adjusting the refrigerating capacity of a refrigerating machine according to claim 4, wherein the refrigerant circulation amount in the refrigerant compressor is controlled to change the pressure level while maintaining the compression ratio of the compressor substantially constant. . 6. A method for adjusting the refrigerating capacity of a refrigerator using a Brighton cycle or a Claude cycle, in which the temperature of the object to be cooled or the outlet of the cooler is detected, and the amount of refrigerant circulated in the refrigerant compressor is adjusted according to the detected temperature; A method for adjusting the refrigerating capacity of a refrigerating machine, which comprises adjusting the amount of cold generated by the refrigerating machine. 7. In a method for adjusting the refrigerating capacity of a refrigerator using a Brighton cycle or a Claude cycle, the temperature of the object to be cooled or the outlet of the cooler is detected, and the compression ratio of the refrigerant compressor is maintained approximately constant based on the detected temperature. 1. A method for adjusting the refrigerating capacity of a refrigerating machine, the method comprising: adjusting the amount of cold generated by the refrigerating machine by changing the pressure level while 8. The method for adjusting the refrigerating capacity of a refrigerator according to any one of claims 4 to 7, wherein the refrigerant compressor is a volumetric compressor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12491390A JP2873388B2 (en) | 1990-05-15 | 1990-05-15 | Refrigerator and method for adjusting refrigeration capacity |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12491390A JP2873388B2 (en) | 1990-05-15 | 1990-05-15 | Refrigerator and method for adjusting refrigeration capacity |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0420754A true JPH0420754A (en) | 1992-01-24 |
| JP2873388B2 JP2873388B2 (en) | 1999-03-24 |
Family
ID=14897219
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12491390A Expired - Fee Related JP2873388B2 (en) | 1990-05-15 | 1990-05-15 | Refrigerator and method for adjusting refrigeration capacity |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2873388B2 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008232455A (en) * | 2007-03-16 | 2008-10-02 | Osaka City Univ | Dilution refrigerating machine |
| JP2012189314A (en) * | 2011-03-08 | 2012-10-04 | Linde Ag | Refrigeration equipment |
| JP2015227775A (en) * | 2010-05-12 | 2015-12-17 | ブルックス オートメーション インコーポレイテッド | System for cryogenic cooling |
| EP2940406A4 (en) * | 2013-05-31 | 2016-06-15 | Maekawa Seisakusho Kk | Brayton cycle refrigeration device |
-
1990
- 1990-05-15 JP JP12491390A patent/JP2873388B2/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008232455A (en) * | 2007-03-16 | 2008-10-02 | Osaka City Univ | Dilution refrigerating machine |
| JP2015227775A (en) * | 2010-05-12 | 2015-12-17 | ブルックス オートメーション インコーポレイテッド | System for cryogenic cooling |
| US10156386B2 (en) | 2010-05-12 | 2018-12-18 | Brooks Automation, Inc. | System and method for cryogenic cooling |
| JP2012189314A (en) * | 2011-03-08 | 2012-10-04 | Linde Ag | Refrigeration equipment |
| EP2940406A4 (en) * | 2013-05-31 | 2016-06-15 | Maekawa Seisakusho Kk | Brayton cycle refrigeration device |
| EP3153795A1 (en) * | 2013-05-31 | 2017-04-12 | Mayekawa Mfg. Co., Ltd. | Brayton cycle refrigerating apparatus |
| US9863669B2 (en) | 2013-05-31 | 2018-01-09 | Mayekawa Mfg. Co., Ltd. | Brayton cycle type refrigerating apparatus |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2873388B2 (en) | 1999-03-24 |
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