JPS6277548A - Refrigerator - Google Patents

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

【発明の詳細な説明】 いて超低温を得る冷凍装置に関する。[Detailed description of the invention] The present invention relates to a refrigeration system that obtains ultra-low temperatures.

〔従来の技術〕[Conventional technology]

従来、非共沸混合冷媒を用いて超低温を得る冷凍装置と
して、第１図に示す構成のものは既に公知である。この
システムは、圧縮機１から吐出した非共沸混合冷媒ガス
を第１凝縮器２で一部凝縮し、次いで気液分離器３でよ
り高沸点成分の液とより低沸点成分のガスとに分離して
、液は分流経路を第２膨張弁８で減圧後、二重管形カス
ケード熱交換器４の内管部の第２蒸発器４を通り圧縮機
１の吸入管路に達する。一方、ガスは主冷媒回路を該二
重管形カスケード熱交換器４を形成する第２凝縮器４を
経て、第１膨張弁６で減圧、第１蒸発器７で超低温を発
生した後、前記高沸点成分と合流、次いで圧縮機１に吸
入し冷凍サイクルを形成している。このような冷凍装置
では、常温で凝縮する冷媒以外に、沸点が低く常温で凝
縮しない冷媒を多量に含む混合冷媒が使用されるため、
冷媒回路内の圧力が上昇し、特に起動時には実使用でき
ない程、″吐出圧力が異常高圧になる欠点があった。異
常高圧の主原因は、停止時のバランス圧力が高く、した
がって起動直後の圧縮機吐出量が非常に大きくなるため
である。さらに、起動直後は第２蒸発器４が部材の熱容
量などによって冷却力が十分得られないことや、低沸点
冷媒成分が主冷媒回路に十分滞留していないため、こと
さら圧力上昇を助長している。2. Description of the Related Art Conventionally, as a refrigeration system that obtains an ultra-low temperature using a non-azeotropic mixed refrigerant, one having the configuration shown in FIG. 1 has already been known. In this system, a non-azeotropic mixed refrigerant gas discharged from a compressor 1 is partially condensed in a first condenser 2, and then separated into a liquid with a higher boiling point component and a gas with a lower boiling point component in a gas-liquid separator 3. After being separated, the liquid passes through the branch path to reduce the pressure at the second expansion valve 8, passes through the second evaporator 4 in the inner tube portion of the double-tube cascade heat exchanger 4, and reaches the suction line of the compressor 1. On the other hand, the gas passes through the main refrigerant circuit through the second condenser 4 forming the double-tube cascade heat exchanger 4, is depressurized by the first expansion valve 6, is heated to an extremely low temperature by the first evaporator 7, and then It is combined with high boiling point components and then sucked into the compressor 1 to form a refrigeration cycle. Such refrigeration equipment uses a mixed refrigerant that contains a large amount of refrigerant that has a low boiling point and does not condense at room temperature, in addition to a refrigerant that condenses at room temperature.
The pressure in the refrigerant circuit increases, and the discharge pressure becomes abnormally high, especially at startup, to the point where it cannot be used in practice.The main cause of the abnormally high pressure is that the balance pressure is high at the time of shutdown, and therefore the compression immediately after startup This is because the machine discharge amount becomes extremely large.Furthermore, immediately after startup, the second evaporator 4 may not be able to obtain sufficient cooling power due to the heat capacity of its components, and low boiling point refrigerant components may not sufficiently accumulate in the main refrigerant circuit. This is particularly contributing to the rise in pressure.

〔解決しようとする問題点〕[Problem to be solved]

本発明の目的は、起動時における圧力上昇を抑えて安全
なプルダウン運転が行える超低温冷凍装置を提供するこ
とにある。An object of the present invention is to provide an ultra-low temperature refrigeration system that can perform safe pull-down operation by suppressing pressure rise during startup.

〔問題点を解決するための手段および作用〕本発明は、
特にこの種の冷凍装置において、第２凝縮器と第１膨張
弁の間に開閉弁を介設し、圧縮機の起動に際し該開閉弁
を閉止して第１膨張弁を通しての流れを停止し、分流経
路の第２膨張弁だけを絞り装置として使用することによ
り速かに圧縮機の吸入圧力を低下させ、さらに第２蒸発
器内の温度も所定の低温に下がった時点で、該開閉弁を
開放する構成としたものである。この次め、起動時、圧
縮機の吸入ガス量は、第１蒸発器に滞留していたものと
第２膨張弁を通して流入するものに限定されるため、起
動直後の圧力上昇を小さく抑えることができる。つづい
て第２蒸発器内の温度が下がって低沸点成分冷媒が第２
凝縮器内に凝縮液化して溜まりだ・すと、循環冷媒が高
沸点成分側に濃度変化し、高圧圧力はますます低下して
安全運転に入ることができ、所期の目的を達成すること
ができる。[Means and effects for solving the problems] The present invention has the following features:
In particular, in this type of refrigeration system, an on-off valve is interposed between the second condenser and the first expansion valve, and when the compressor is started, the on-off valve is closed to stop the flow through the first expansion valve. By using only the second expansion valve in the split flow path as a throttling device, the suction pressure of the compressor is quickly reduced, and when the temperature inside the second evaporator has also fallen to a predetermined low temperature, the opening/closing valve is turned on. It is configured to be open. Next, at startup, the amount of gas taken into the compressor is limited to the amount of gas remaining in the first evaporator and that flowing in through the second expansion valve, making it possible to keep the pressure rise to a small level immediately after startup. can. Subsequently, the temperature in the second evaporator decreases and the low boiling point component refrigerant flows into the second evaporator.
When the refrigerant condenses and liquefies and accumulates in the condenser, the concentration of the circulating refrigerant changes to the higher boiling point component side, and the high pressure decreases further, enabling safe operation and achieving the intended purpose. I can do it.

〔実施例〕〔Example〕

以下１本発明の一実施例を第２図により説明する。圧縮
機１、第１凝縮器２、気液分離器３、第２凝縮器４′、
第１膨張弁６、第１蒸発器７、第２膨張弁８、第２蒸発
器４を要素とした構成は、第１図の従来装置と同一であ
り、本発明では更に主冷媒回路の気液分離器３、第２凝
縮器４間に逆止弁９を、第２凝縮器４、第１膨張弁６間
に開閉弁、例えば電磁弁５を介設している０ この冷媒回路の運転は、次のように行われる。An embodiment of the present invention will be described below with reference to FIG. Compressor 1, first condenser 2, gas-liquid separator 3, second condenser 4',
The configuration including the first expansion valve 6, first evaporator 7, second expansion valve 8, and second evaporator 4 is the same as the conventional device shown in FIG. A check valve 9 is interposed between the liquid separator 3 and the second condenser 4, and an on-off valve, such as a solenoid valve 5, is interposed between the second condenser 4 and the first expansion valve 6. is performed as follows.

まず装置の起動に際して、電磁弁５を閉止しておく。こ
の状態で、圧縮機１から吐出され几冷媒は、一部凝縮器
２で液化し、気液分離器３で高沸点成分の液と低沸点成
分のガスとに分離される。液は第２膨張弁８を経て第２
蒸発器４に到り、そこで冷却作用の後、圧縮機１の吸入
側に戻る。以下同様の循環が繰返される。一方、低沸点
成分のガスは、第２蒸発器４の冷却作用の進展にともな
い、逆止弁９を経て第２凝縮器４内に液化、貯留されて
いく。ここで、起動時、圧縮機１に吸入される冷媒は、
第１蒸発器７内滞留分と第２膨張弁８通過分に限定され
るため、起動直後の高圧圧力上昇−め高圧圧力の低下を
助長し、速かに安全運転に移ることかできる。その後、
高圧圧力が十分低下し、第２蒸発器４出口温度も所定温
度に下がったことを、別途センサ（図示せず）により検
知し電磁弁５を開くことにより、定常運転に入ることが
できる０なお、ここで定常運転後、圧縮機１の停止と止
弁９と電磁弁５の作用で定常運転時に第２凝縮器４に滞
留していた低沸点冷媒成分をそのまま封止込むことがで
き、起動時の高圧圧力上昇をより効果的に抑制す慝こと
ができる。こうすることで、従来一般に運転停止時のバ
ランス圧力低下を狙った膨張タンクを設置不要にするこ
ともできる。また、起動運転や０Ｎ−ＯＦＦ！転じた場
合の冷凍サイクル内冷媒濃度分布の安定化を早めること
もできる。First, when starting up the device, the solenoid valve 5 is closed. In this state, the liquefied refrigerant discharged from the compressor 1 is partially liquefied in the condenser 2, and separated into a high-boiling component liquid and a low-boiling component gas in the gas-liquid separator 3. The liquid passes through the second expansion valve 8 and enters the second
It reaches the evaporator 4 where, after a cooling effect, it returns to the suction side of the compressor 1. The same cycle is repeated thereafter. On the other hand, as the cooling action of the second evaporator 4 progresses, the low boiling point component gas passes through the check valve 9 and is liquefied and stored in the second condenser 4. Here, the refrigerant sucked into the compressor 1 at startup is:
Since it is limited to the amount that remains in the first evaporator 7 and the amount that passes through the second expansion valve 8, the increase in high pressure immediately after startup and the decrease in high pressure are promoted, and safe operation can be quickly started. after that,
A separate sensor (not shown) detects that the high pressure has decreased sufficiently and the temperature at the outlet of the second evaporator 4 has also decreased to a predetermined temperature, and by opening the solenoid valve 5, steady operation can be started. After steady operation, the low boiling point refrigerant component that had remained in the second condenser 4 during steady operation can be sealed as it is by stopping the compressor 1 and the action of the stop valve 9 and the solenoid valve 5. It is possible to more effectively suppress the rise in high-pressure pressure at the time of use. By doing so, it is also possible to eliminate the need to install an expansion tank that conventionally aims to reduce the balance pressure when the operation is stopped. Also, starting operation and 0N-OFF! It is also possible to hasten the stabilization of the refrigerant concentration distribution in the refrigeration cycle in the case of a change.

〔発明の効果〕〔Effect of the invention〕

本発明によれば、起動時の高圧圧力上昇を小さく抑え、
速かに安全運転を行わせるようにするこ第１図は従来の
冷凍装置回路図０第２図は本発明の冷凍装置回路図であ
る。According to the present invention, the rise in high pressure at startup is suppressed to a small level,
Figure 1 is a circuit diagram of a conventional refrigeration system, and Figure 2 is a circuit diagram of a refrigeration system according to the present invention.

図面において、１：圧縮機、２：第１凝縮器、３：気液
分離器、４：二重管形カスケード熱交換弁、６：第１膨
張弁、７：第１蒸発器、８：第２膨張弁、９：逆止弁。In the drawings, 1: compressor, 2: first condenser, 3: gas-liquid separator, 4: double pipe cascade heat exchange valve, 6: first expansion valve, 7: first evaporator, 8: first 2 expansion valve, 9: check valve.

ｈ４濃人　　ｋ明１０工ｔｎ伐４；ネ工第１図 第２図 手続補正書 昭和。。年０、月口日　　１ 昭和６０年　特許願　第２１５２８９号２、発明の名称 冷凍装置　　　　　　　　　　　　　　　　。h4 thick man k Ming 10 work tn cutting 4; Ne work Figure 1 Figure 2 Procedural amendment Showa. . Year 0, month end date 1 1985 Patent Application No. 215289 2, Title of Invention Refrigeration equipment.

３、補正をする者 ン 事件との関係　　特許出願人 住所　　兵庫県西宮市小曽根町１丁目５番２５号名称　
　（２８５＞　新明和工業株式会社代表者　玉　河　晋
　次 ４、補正命令の日付 自　　発 ５、補正により増加する発明の数 な　　し ６、補正の対象 明細書の第６ページ第１０行目と第１１行目の蜀に下記
の文を補充する。3. Relationship with the person making the amendment Patent applicant address 1-5-25 Kozone-cho, Nishinomiya City, Hyogo Prefecture Name
(285> ShinMaywa Industries Co., Ltd. Representative Susumuji Tamagawa 4. Date of amendment order 5. No increase in the number of inventions due to the amendment 6. Page 6, line 10 of the specification subject to amendment Add the following sentence to Shu in line 11.

記 以上、本実施例によれば、第１膨張弁の作用を亭止させ
ることで、起動時の高圧圧力上昇を小さく抑えることが
できる、さらに低沸点冷媒成分をｇ２凝縮器に液として
貯留することにより、高圧圧力の低下を助長することが
できる、また、第２距縮器入口に逆止弁を設けることに
より停止時のべ２ンス圧力を下げるための膨張タンクを
不要にすることもできるなどの効果がある。As described above, according to this embodiment, by stopping the action of the first expansion valve, the high pressure rise at startup can be suppressed to a small level, and furthermore, the low boiling point refrigerant component is stored as a liquid in the g2 condenser. By providing a check valve at the inlet of the second range condenser, an expansion tank for lowering the base pressure during stoppage can be eliminated. There are effects such as

Claims (2)

【特許請求の範囲】[Claims] （１）非共沸混合冷媒を用い、圧縮機、第１凝縮器、気
液分離器、第２凝縮器、第１膨張弁、第１蒸発器を順次
環状に配管接続する主冷媒回路と、前記気液分離器と前
記圧縮機の吸入管路の間を第２膨張弁、および前記第２
凝縮器と熱交換可能な状態にある第２蒸発器を接続する
分流経路とを有するものにおいて、前記第２凝縮器と第
１膨張弁を連絡する管路に開閉弁を介設し、前記圧縮機
起動後、所定の時間該開閉弁を閉止する構成としたこと
を特徴とする冷凍装置。(1) A main refrigerant circuit using a non-azeotropic mixed refrigerant and sequentially connecting a compressor, a first condenser, a gas-liquid separator, a second condenser, a first expansion valve, and a first evaporator with piping in an annular manner; A second expansion valve and a second expansion valve are connected between the gas-liquid separator and the suction pipe line of the compressor.
In the device having a branch path connecting the condenser and a second evaporator in a state where heat exchange is possible, an on-off valve is interposed in a pipe connecting the second condenser and the first expansion valve, and the compression A refrigeration system characterized in that the opening/closing valve is closed for a predetermined period of time after the machine is started. （２）前記気液分離器と第２凝縮器を連絡する管路に、
逆止弁を介設した特許請求の範囲第１項記載の冷凍装置
。(2) A pipe connecting the gas-liquid separator and the second condenser,
The refrigeration system according to claim 1, which includes a check valve.