JPH0297870A - Refrigerating machine - Google Patents
Refrigerating machineInfo
- Publication number
- JPH0297870A JPH0297870A JP25149188A JP25149188A JPH0297870A JP H0297870 A JPH0297870 A JP H0297870A JP 25149188 A JP25149188 A JP 25149188A JP 25149188 A JP25149188 A JP 25149188A JP H0297870 A JPH0297870 A JP H0297870A
- Authority
- JP
- Japan
- Prior art keywords
- flow path
- path resistance
- cooler
- freezing
- increase
- 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
- 238000001514 detection method Methods 0.000 claims abstract description 17
- 230000005856 abnormality Effects 0.000 claims abstract description 14
- 239000007788 liquid Substances 0.000 claims abstract description 14
- 230000002159 abnormal effect Effects 0.000 claims abstract description 5
- 238000001816 cooling Methods 0.000 claims description 4
- 238000007710 freezing Methods 0.000 abstract description 23
- 230000008014 freezing Effects 0.000 abstract description 23
- 239000012267 brine Substances 0.000 abstract description 11
- HPALAKNZSZLMCH-UHFFFAOYSA-M sodium;chloride;hydrate Chemical compound O.[Na+].[Cl-] HPALAKNZSZLMCH-UHFFFAOYSA-M 0.000 abstract description 11
- 230000000694 effects Effects 0.000 abstract description 4
- 238000000034 method Methods 0.000 abstract description 2
- 230000003247 decreasing effect Effects 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 5
- 239000003507 refrigerant Substances 0.000 description 5
- 238000005057 refrigeration Methods 0.000 description 2
- 230000002123 temporal effect Effects 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000005070 sampling Methods 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〕
本発明は冷凍機で凍結温度付近の液体を製造中に被冷却
液体が凍結した場合に、この凍結を解除し連続運転を可
能とした冷凍機に関するものである。なお、本明細書に
おいて、プラインとは冷水その他の被冷却水を指すもの
とする。[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a refrigeration system that unfreezes the liquid to be cooled and enables continuous operation when the liquid to be cooled freezes during the production of liquid near the freezing temperature in a refrigeration machine. It's about machines. Note that in this specification, prine refers to cold water or other water to be cooled.
従来この種の冷凍機としては、実願昭55−12893
3号(公開実用昭和57−50670)の明細書及び図
面に開示されたものがあった。この冷凍機は、冷却内で
プラインが凍った場合に、流路壁や伝熱管表面に氷が付
着して流路断面積が減少し、プラインの流路抵抗が増大
することを利用して、該流路抵抗が所定の設定値を越え
た時に、冷凍機の容量を減少させて凍結を解除するよう
に構成されていた。即ち、第5図に示す如く、凍結の発
生していない通常の状態での流路抵抗Bが、時点t、で
プラインの凍結発生によって増大し、設定値Aを越えた
時点t1において、異常検出がされ、冷凍機容量を減少
させる凍結解除動作を開始するようになっている。Conventionally, this type of refrigerator was manufactured by Utility Application No. 55-12893.
There was something disclosed in the specification and drawings of No. 3 (Public Publication of Practical Use 1984-50670). This refrigerator takes advantage of the fact that when the plines freeze in the cooling chamber, ice adheres to the channel walls and the surface of the heat transfer tube, reducing the channel cross-sectional area and increasing the flow resistance of the plines. When the flow path resistance exceeds a predetermined set value, the capacity of the refrigerator is reduced to release the freezing. That is, as shown in FIG. 5, the flow path resistance B in a normal state without freezing increases at time t due to the occurrence of freezing of the pline, and at time t1 when it exceeds the set value A, an abnormality is detected. is started, and an unfreezing operation that reduces the capacity of the refrigerator is started.
上記の如〈従来この種の冷凍機は、通常の状態での流路
抵抗Bが、ブラインの凍結発生(時点t、)によって増
大し、流路抵抗が設定値Aを越えた時点t、において、
冷凍機容量を減少させる凍結解除動作を開始するため、
冷却器内で凍結が発生した場合、流路抵抗が通常の状態
Bから設定値Aに増加するまでの間異常を検出すること
ができず、凍結発生の時点t1から異常検出の時点t、
までの所用時間Cが長いものになってしまうという欠点
があった。As mentioned above, in conventional refrigerators of this type, the flow path resistance B in the normal state increases when the brine freezes (time t), and at the time t when the flow path resistance exceeds the set value A. ,
To start the unfreezing operation that reduces the refrigerator capacity,
When freezing occurs in the cooler, an abnormality cannot be detected until the flow path resistance increases from the normal state B to the set value A, and from the time t1 of freezing occurrence to the time t of abnormality detection,
The disadvantage is that the time C required to complete the process is long.
また、所用時間Cを短くするために設定値Aを通常の流
路抵抗Bの近傍に設定した場合、設定値Aと通常の流路
抵抗Bの差が小さくなり、流路抵抗が設定値Aから元の
通常の流路抵抗Bに復帰したことを検出することが難し
くなる。従って、流路抵抗が元の通常の流路抵抗Bに復
帰したことによって、凍結の解除を検出して凍結解除動
作を終了させることができないという不都合があった。Furthermore, if the set value A is set close to the normal flow path resistance B in order to shorten the required time C, the difference between the set value A and the normal flow path resistance B becomes small, and the flow path resistance becomes the set value A. It becomes difficult to detect that the flow path resistance B has returned to the original normal flow path resistance. Therefore, since the flow path resistance has returned to the original normal flow path resistance B, there is a problem in that it is not possible to detect the unfreezing and complete the unfreezing operation.
本発明は上述の点に鑑みてなされたもので、凍結発生か
ら異常検出までの所用時間が短く、且つ流路抵抗が通常
の状態に復帰したら直ちに凍結解除動作を終了させるこ
とができる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 points, and provides a refrigerator that takes a short time from the occurrence of freezing to the detection of an abnormality, and can immediately terminate the unfreezing operation once the flow path resistance returns to the normal state. It is about providing.
上記課題を解決するため本発明は冷凍機を、冷却器と、
該冷却器内を流れる被冷却液体の流路抵抗を検出する流
路抵抗検出手段と、該、流路抵抗の所定時間毎の増加量
が設定増加量を越えた場合に冷却器の冷却容量を減少制
御する容量制御装置とを具備する構成とした。In order to solve the above problems, the present invention includes a refrigerator, a cooler,
a flow path resistance detection means for detecting the flow path resistance of the liquid to be cooled flowing in the cooler; and the cooling capacity of the cooler when the amount of increase in the flow path resistance at each predetermined time exceeds a set increase amount. The structure includes a capacity control device that performs reduction control.
また、前記冷凍機において、流路抵抗が所定の許容範囲
を越えて異常となった場合に、異常検出及び容量減少動
作を開始する構成とした。Furthermore, the refrigerator is configured to start abnormality detection and capacity reduction operation when the flow path resistance exceeds a predetermined allowable range and becomes abnormal.
また、前記冷凍機において、流路抵抗検出手段として、
冷却器における被冷却液体の出入口での圧力差を検出し
て流路抵抗を検出する手段を用いる構成とした。Further, in the refrigerator, as a flow path resistance detection means,
The configuration uses means for detecting the pressure difference at the inlet and outlet of the liquid to be cooled in the cooler to detect the flow path resistance.
冷凍機を上記の如く構成することにより、冷却容量の減
少制御を流路抵抗の所定時間毎の増加量が設定増加量を
越えたか否かで行なうので、従来の冷凍機に比較し、凍
結を早期に検出できその解除が可能になると共に、凍結
検出の信頼性が向上し、凍結点付近の液体の製造を安定
的に連続して行なうことが可能となる。By configuring the refrigerator as described above, the cooling capacity is controlled to decrease depending on whether the amount of increase in flow path resistance at each predetermined time exceeds the set increase amount, so compared to conventional refrigerators, freezing is reduced. It is possible to detect the freeze at an early stage and release it, and the reliability of the freeze detection is improved, making it possible to stably and continuously produce a liquid near the freezing point.
以下、本発明の実施例を図面に基づいて説明する。 Embodiments of the present invention will be described below based on the drawings.
第1図は本発明に係る冷凍機の構成を示す図である。同
図において、3は冷媒を冷却する冷却器、4はブライン
入口、5はブライン出口、6はブライン人口4とブライ
ン出口5との圧力差を検出して伝送する差圧伝送器、7
はマイクロコンピュータ、8は冷凍機の容量を制御する
容量制御装置、9は伝熱管、10は冷媒入口、11は冷
媒出口である。マイクロコンピュータ7は差圧伝送器6
の出力(ブライン人口4とブライン出口5との圧力差)
かも流路抵抗を検出し、との流路抵抗の増加量が所定の
設定増加量を越えたか否かの判断し、流路抵抗が後述す
る不感帯Hを越えたことによる異常検出及び容量制御装
置8の容量減少動作開始するかの判断を行なうものであ
る。このマイクロコンピュータ7は容量制御装置8に搭
載されている。FIG. 1 is a diagram showing the configuration of a refrigerator according to the present invention. In the figure, 3 is a cooler that cools the refrigerant, 4 is a brine inlet, 5 is a brine outlet, 6 is a differential pressure transmitter that detects and transmits the pressure difference between the brine population 4 and the brine outlet 5, and 7
1 is a microcomputer, 8 is a capacity control device for controlling the capacity of the refrigerator, 9 is a heat exchanger tube, 10 is a refrigerant inlet, and 11 is a refrigerant outlet. The microcomputer 7 is a differential pressure transmitter 6
output (pressure difference between brine population 4 and brine outlet 5)
A capacity control device that detects flow path resistance, determines whether the increase in flow path resistance exceeds a predetermined set increase amount, and detects an abnormality when the flow path resistance exceeds a dead zone H, which will be described later. It is determined whether or not to start the capacity reduction operation of step 8. This microcomputer 7 is installed in a capacity control device 8.
上記構成の冷凍機において、冷却器3の内部でブライン
の凍結が始まった場合、流路壁や伝熱管9の表面に氷が
付着していき、流路断面が次第に減少して、冷却器3に
おけるブラインの流路抵抗が増加する傾向を示す。この
流路抵抗の増加していく傾向に着目し、早期に凍結を検
出するために、マイクロコンピュータ7は所定時間ごと
に差圧伝送器6の出力から、流路抵抗を算定し、この流
路抵抗の増加量が所定の設定増加量を越えて異常となっ
た場合に、冷凍機の容量を減少させて凍結の解除を行な
うように構成されている。即ち、第2図において、凍結
の発生していない状態での流路抵抗りが、凍結の発生す
る時点t、から増加を始め、所定時間E(サンプリング
時間)ごとの増加量Fが所定の設定増加量を越えた場合
に異常(凍結)の検出を行ない、容量減少制御を行なう
。また、流路抵抗は第3図に示すように、プラインの凍
結が発生していない通常の状態Gでも、凍結とは無関係
な流量の変動等に起因する流路抵抗の微ノド変動があり
、前記変動中に現れる流路抵抗の増加傾向による誤った
異常検出を防止するために流路抵抗の前記変動を包含す
るような許容範囲、所謂不感帯Hを設定し、プラインの
凍結が発生して流路抵抗がこの不感帯Hを越えて増加し
た時点t、において、異常検出及び容量制御装置8の動
作を開始させるように構成している。In the refrigerator having the above configuration, when the brine begins to freeze inside the cooler 3, ice will adhere to the flow path walls and the surfaces of the heat transfer tubes 9, and the cross section of the flow path will gradually decrease. The brine flow path resistance tends to increase. Focusing on this tendency of increasing flow path resistance, in order to detect freezing early, the microcomputer 7 calculates the flow path resistance from the output of the differential pressure transmitter 6 at predetermined intervals, and If the amount of increase in resistance exceeds a predetermined set amount of increase and becomes abnormal, the capacity of the refrigerator is reduced to remove the freezing. That is, in FIG. 2, the flow path resistance in a state where no freezing has occurred starts to increase from time point t when freezing occurs, and the amount of increase F for each predetermined time E (sampling time) is set at a predetermined setting. If the increased amount is exceeded, an abnormality (freezing) is detected and capacity reduction control is performed. Furthermore, as shown in Fig. 3, even in the normal state G where no freezing of the line occurs, there are slight fluctuations in the flow path resistance due to fluctuations in flow rate unrelated to freezing. In order to prevent erroneous abnormality detection due to the increasing tendency of the flow path resistance that appears during the fluctuations, a tolerance range that includes the fluctuations in the flow path resistance, the so-called dead zone H, is set. At time t when the road resistance increases beyond this dead zone H, the abnormality detection and capacity control device 8 is configured to start operating.
第4図は上記構成の冷凍機の動作を示すフローチャート
である。差圧伝送器6は前述のように、冷却器3におけ
るプライン人口4及びプライン出口5の圧力差を検出し
マイクロコンピュータ7に伝送している。マイクロコン
ピュータ7は、差圧伝送器6からの圧力差を所定時間ご
とにサンプリングし、該圧力差から流路抵抗を検出する
(ステップ101 )、前記圧力差をサンプリングして
検出した流路抵抗が許容範囲(第3図の不感帯H)に収
まっているか否かを判断しくステップ102)、収まっ
ている場合は、このサンプリングして検出、した流路抵
抗をマイクロコンピュータ7のメモリに格納する(ステ
ップ103)、プラインの凍結により、サンプリングし
た圧力差が許容範囲を越えた場合は、メモリ内に格納し
である所定時間前の流路抵抗との差から流路抵抗の増加
量を算出し、該流路抵抗の増加量が設定増加量を越えた
か否を判断しくステップ104)、流路抵抗の増加量が
設定増加量を越えた場合には、i量制御装置8に異常検
出信号を出力して、容量減少動作による凍結解除を行な
い(ステップ105)、その流路抵抗をメモリ内に格納
する(ステップ102)、また、前記ステップ104に
おいて、流路抵抗の増加量が設定増加量を越えない場合
もその流路抵抗をメモリ内に格納する(ステップ102
)。FIG. 4 is a flowchart showing the operation of the refrigerator configured as described above. As described above, the differential pressure transmitter 6 detects the pressure difference between the line inlet 4 and the line outlet 5 in the cooler 3 and transmits it to the microcomputer 7. The microcomputer 7 samples the pressure difference from the differential pressure transmitter 6 at predetermined time intervals and detects the flow path resistance from the pressure difference (step 101). It is determined whether or not it falls within the allowable range (dead zone H in FIG. 3) (step 102), and if it falls within the tolerance range (dead zone H in FIG. 3), the sampled and detected flow path resistance is stored in the memory of the microcomputer 7 (step 102). 103) If the sampled pressure difference exceeds the allowable range due to freezing of the line, calculate the amount of increase in flow path resistance from the difference from the flow path resistance stored in memory a predetermined time ago, and It is determined whether the increase amount of the flow path resistance exceeds the set increase amount (step 104), and if the increase amount of the flow path resistance exceeds the set increase amount, an abnormality detection signal is output to the i-quantity control device 8. Then, unfreezing is performed by a capacity reduction operation (step 105), and the flow path resistance is stored in memory (step 102), and in step 104, it is determined that the amount of increase in the flow path resistance does not exceed the set increase amount. In this case, the flow path resistance is also stored in memory (step 102).
).
なお、前記マイクロコンピュータ7でサンプリングする
圧力差は所定時間ごとの平均圧力差でもよく、この圧力
差から流路抵抗を検出してもよい、また、異常検出の確
度を向上させるために、マイクロコンピュータ7におい
て、連続或いは断続的に所定回数の異常検出が行なわれ
た場合に、異常検出信号を容量制御装置8に出力するよ
うにしてもよい。Note that the pressure difference sampled by the microcomputer 7 may be an average pressure difference at predetermined time intervals, and the flow path resistance may be detected from this pressure difference. In step 7, an abnormality detection signal may be output to the capacity control device 8 when abnormality detection is performed a predetermined number of times continuously or intermittently.
以上、説明したように本発明によれば、冷却器における
被冷却液体の流路抵抗の所定時間ごとの増加量が所定の
設定増加量を越えて異常となった場合に、容量減少制御
を行なう容量制御装置を備えることにより、従来のこの
種の冷凍機に比較し、早期に被冷却液体の凍結を検出し
、その凍結を解除することを可能にすると共に、凍結の
検出に関する信頼性を向上させ、凍結点付近の液体を製
造する冷凍機の安定した連続運転を可能とするという優
れた効果が得られる。As explained above, according to the present invention, when the amount of increase in the flow path resistance of the liquid to be cooled in the cooler at each predetermined time exceeds a predetermined set increase amount and becomes abnormal, capacity reduction control is performed. Equipped with a capacity control device, compared to conventional refrigerators of this type, it is possible to detect freezing of the liquid to be cooled and unfreeze it earlier, and improve the reliability of freezing detection. This provides the excellent effect of enabling stable continuous operation of a refrigerator that produces liquid near the freezing point.
第1図は本発明の冷凍機の構成を示す図、第2図及び第
3図は本発明の冷凍機の流路抵抗の時間的変化を示す図
、第4図は本発明の冷凍機の動作を示すフローチャート
、第5図は従来の冷凍機における流路抵抗の時間的変化
を示す図である。
図中、3・・・・冷却器、4・・・・プライン入口、5
・・・・プライン出口、6・・・・差圧伝送器、7・・
・・マイクロコンピュータ、8・・・・容量制御装置、
9・・・・伝熱管、10・・・・冷媒入口、11・・・
・冷媒出口。
代理人 弁理士 熊 谷 隆(外1名)第3
図
第5
図
両q−
欝藺
截ムイ―FIG. 1 is a diagram showing the configuration of the refrigerator of the present invention, FIGS. 2 and 3 are diagrams showing temporal changes in flow path resistance of the refrigerator of the present invention, and FIG. 4 is a diagram showing the structure of the refrigerator of the present invention. A flowchart showing the operation, FIG. 5 is a diagram showing temporal changes in flow path resistance in a conventional refrigerator. In the figure, 3... Cooler, 4... Pline inlet, 5
...Pline outlet, 6...Differential pressure transmitter, 7...
...Microcomputer, 8...Capacity control device,
9... Heat exchanger tube, 10... Refrigerant inlet, 11...
・Refrigerant outlet. Agent Patent attorney Takashi Kumagai (1 other person) Figure 3 Figure 5
Claims (3)
抵抗を検出する流路抵抗検出手段と、該流路抵抗の所定
時間毎の増加量が設定増加量を越えた場合に冷却器の冷
却容量を減少制御する容量制御装置とを具備することを
特徴とする冷凍機。(1) A cooler, a flow path resistance detection means for detecting the flow path resistance of the liquid to be cooled flowing in the cooler, and a flow path resistance detection means for detecting the flow path resistance of the liquid to be cooled flowing within the cooler; A refrigerator comprising: a capacity control device that controls a reduction in the cooling capacity of a cooler.
った場合に、異常検出及び前記容量制御の容量減少動作
を開始することを特徴とする請求項(1)記載の冷凍機
。(2) The refrigerator according to claim 1, wherein when the flow path resistance exceeds a predetermined allowable range and becomes abnormal, the abnormality detection and the capacity reduction operation of the capacity control are started.
冷却液体の出入口での圧力差を検出して流路抵抗を検出
する手段を用いることを特徴とする請求項(1)又は(
2)記載の冷凍機。(3) As the flow path resistance detection means, means for detecting the flow path resistance by detecting a pressure difference between the inlet and outlet of the liquid to be cooled in the cooler is used.
2) The refrigerator described.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP63251491A JPH0711373B2 (en) | 1988-10-04 | 1988-10-04 | refrigerator |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP63251491A JPH0711373B2 (en) | 1988-10-04 | 1988-10-04 | refrigerator |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH0297870A true JPH0297870A (en) | 1990-04-10 |
JPH0711373B2 JPH0711373B2 (en) | 1995-02-08 |
Family
ID=17223589
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP63251491A Expired - Fee Related JPH0711373B2 (en) | 1988-10-04 | 1988-10-04 | refrigerator |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH0711373B2 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH05133693A (en) * | 1991-11-12 | 1993-05-28 | Daikin Ind Ltd | Water cooling device |
JPWO2021166040A1 (en) * | 2020-02-17 | 2021-08-26 |
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JPS6191438A (en) * | 1984-10-11 | 1986-05-09 | Matsushita Electric Ind Co Ltd | Method of controlling defrosting of heat pump type air conditioner |
JPS6330938A (en) * | 1986-07-24 | 1988-02-09 | Nec Corp | Microprogram control device |
JPS6330938U (en) * | 1986-08-19 | 1988-02-29 |
-
1988
- 1988-10-04 JP JP63251491A patent/JPH0711373B2/en not_active Expired - Fee Related
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
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JPS5839440U (en) * | 1981-09-09 | 1983-03-15 | 株式会社日立製作所 | Defrosting control of air-cooled heat pump air conditioners |
JPS6191438A (en) * | 1984-10-11 | 1986-05-09 | Matsushita Electric Ind Co Ltd | Method of controlling defrosting of heat pump type air conditioner |
JPS6330938A (en) * | 1986-07-24 | 1988-02-09 | Nec Corp | Microprogram control device |
JPS6330938U (en) * | 1986-08-19 | 1988-02-29 |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH05133693A (en) * | 1991-11-12 | 1993-05-28 | Daikin Ind Ltd | Water cooling device |
JPWO2021166040A1 (en) * | 2020-02-17 | 2021-08-26 | ||
WO2021166040A1 (en) * | 2020-02-17 | 2021-08-26 | 三菱電機株式会社 | Refrigeration cycle device |
Also Published As
Publication number | Publication date |
---|---|
JPH0711373B2 (en) | 1995-02-08 |
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