JPH01291083A - Defrosting system for cold air circulating type showcase - Google Patents
Defrosting system for cold air circulating type showcaseInfo
- Publication number
- JPH01291083A JPH01291083A JP12035388A JP12035388A JPH01291083A JP H01291083 A JPH01291083 A JP H01291083A JP 12035388 A JP12035388 A JP 12035388A JP 12035388 A JP12035388 A JP 12035388A JP H01291083 A JPH01291083 A JP H01291083A
- Authority
- JP
- Japan
- Prior art keywords
- defrosting
- cooler
- cold air
- showcase
- liquid refrigerant
- 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
- 238000010257 thawing Methods 0.000 title claims abstract description 135
- 239000003507 refrigerant Substances 0.000 claims abstract description 70
- 239000007788 liquid Substances 0.000 claims abstract description 39
- 238000000034 method Methods 0.000 claims abstract description 22
- 238000001816 cooling Methods 0.000 claims abstract description 12
- 238000007710 freezing Methods 0.000 abstract description 3
- 230000008014 freezing Effects 0.000 abstract description 3
- 238000005286 illumination Methods 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 11
- 238000009423 ventilation Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 5
- 230000007423 decrease Effects 0.000 description 4
- 238000005057 refrigeration Methods 0.000 description 4
- 235000013305 food Nutrition 0.000 description 3
- 235000013372 meat Nutrition 0.000 description 3
- 241000251468 Actinopterygii Species 0.000 description 2
- 230000004397 blinking Effects 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 238000004321 preservation Methods 0.000 description 2
- 230000000717 retained effect Effects 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 235000011389 fruit/vegetable juice Nutrition 0.000 description 1
- 238000011534 incubation Methods 0.000 description 1
- 238000005192 partition Methods 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 238000004781 supercooling Methods 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
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
- F25B2347/00—Details for preventing or removing deposits or corrosion
- F25B2347/02—Details of defrosting cycles
- F25B2347/021—Alternate defrosting
Landscapes
- Defrosting Systems (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は精肉、鮮魚等の生鮮食糧品を扱う冷蔵用オーブ
ンショーケースを対象とした冷気循環形ショーケースの
除霜方式に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a defrosting system for a refrigerated oven showcase for handling perishable foods such as meat and fresh fish.
この種のショーケースに内蔵した冷却器に対する除霜方
式として、従来よりホットガス除霜、ヒ−タ除霜、オフ
サイクル除霜、空気除霜等の各種除霜方式が知られてお
り、かつショーケースの保冷運転の合間を縫ってタイマ
制御等により周期的に除霜を行うようにしている。Various defrosting methods such as hot gas defrosting, heater defrosting, off-cycle defrosting, and air defrosting have been known as defrosting methods for the cooler built into this type of showcase. Defrosting is performed periodically by timer control, etc., in between cold storage operations of the showcase.
一方、ショーケースでは除霜を行っている期間に冷却器
の冷却運転を中断すると、庫内に除霜熱で昇温した空気
が循環して庫内温度を高め、これが原因で庫内に陣列し
た商品の品温が上がって生鮮食糧品の品質劣化を来すお
それがある。On the other hand, in the showcase, if the cooling operation of the cooler is interrupted during the defrosting period, the air heated by the defrosting heat circulates inside the refrigerator, raising the temperature inside the refrigerator, which causes lines to form inside the refrigerator. There is a risk that the product temperature will rise and the quality of fresh foods may deteriorate.
そこで上記のように除霜時における商品の品温上昇を防
止する対策として、冷気循環路に２台の冷却器を並置配
備して冷凍機のコンデンシングユニットに接続し、各冷
却器の除霜を周期的に片方ずつ交互に行うとともに、除
霜時には除霜側の冷却器にコンデンシングユニットから
送出された高温、高圧の液冷媒を直接導入して液冷媒除
霜を行いつつ、該冷却器より出た過冷却の冷媒を他方の
冷却器に供給して冷却運転を継続するようにした除霜方
式が特願昭６２−１１６５１として同じ出願人より既に
提案されている。Therefore, as a measure to prevent the product temperature from rising during defrosting as described above, two coolers are placed side by side in the cold air circulation path and connected to the condensing unit of the refrigerator, and each cooler is defrosted. At the same time, during defrosting, high-temperature, high-pressure liquid refrigerant sent from the condensing unit is directly introduced into the cooler on the defrosting side to perform liquid refrigerant defrosting. The same applicant has already proposed a defrosting system in which the supercooled refrigerant discharged from one cooler is supplied to the other cooler to continue cooling operation.
次に第５＠、第６図により上記提案によるショーケース
の除霜方式を説明する。まず第５図は冷気循環形ショー
ケースの構成を示すもので、１は前面を開口したショー
ケースのケース本体、２は外箱、３は内箱、４は庫内の
商品陳列室であり、外箱２と内箱３と間には仕切壁を介
して内外２層のインチ、アウタ冷気ＷＩＩＷ路５，６が
画成されており、ここでインチ側の冷気循環路５にはイ
ンナフアンマとともに左右に並ぶ２台の冷却器８Ａ、
８Ｂが、またアウタ側の冷気循環路６にはアウタファン
９が設置されている。なお１０は冷却器８＾と８Ｂとの
境に設けていずれか一方の冷却器の通風出口を塞ぐエア
ダンパ、１１は庫内の天井、および各段の商品陳列棚毎
に取付けた庫内照明灯である。Next, the defrosting method for the showcase proposed above will be explained with reference to FIGS. 5 and 6. First, Fig. 5 shows the configuration of a cold air circulation type showcase, where 1 is the main body of the showcase with an open front, 2 is an outer box, 3 is an inner box, and 4 is a product display room inside the warehouse. Two layers of inch and outer cold air WIIW paths 5 and 6 are defined between the outer box 2 and the inner box 3 via a partition wall, and the cold air circulation path 5 on the inch side has left and right channels as well as an inner fan. Two coolers 8A lined up,
8B, and an outer fan 9 is installed in the cold air circulation path 6 on the outer side. Note that 10 is an air damper installed at the boundary between coolers 8^ and 8B to block the ventilation outlet of either cooler, and 11 is an interior lighting lamp installed on the ceiling of the refrigerator and on each product display shelf. It is.
かかるショーケースで、保冷運転時には各冷却器８Ａ、
８Ｂが共に冷却運転され、庫内の冷気循環路５．６に
はそれぞれ矢印Ａ、Ｂで示す冷気が循環通弧し、ケース
本体１の前面間口部に内外２′４の冷気エアカーテンを
吹出し形成し、外気の侵入を遮へいして庫内陳列商品を
保冷する。In such a showcase, during cold storage operation, each cooler 8A,
8B are both in cooling operation, and cold air shown by arrows A and B is circulated through the cold air circulation paths 5 and 6 inside the refrigerator, respectively, and cold air curtains from inside and outside 2'4 are blown out to the front opening of the case body 1. This prevents outside air from entering and keeps the products displayed inside the refrigerator cool.
一方、前記冷却器８＾、 ８Ｂを含む冷媒回路は第６図
の如くである０図において１２は冷凍機のコンデンシン
グユニットであり、該コンデンシングユニット１２に前
記２台の冷却器８＾、８Ｂが並列に配管接続されている
。また１３Ａ、 １３Ｂは膨張弁、１４Ａ、 １４Ｂは
冷却器８Ａ、 ８Ｂおよび膨張弁１３Ａ、 １３Ｂを迂
回するバイパス管路、１５Ａ、 １５Ｂは逆止弁、１６
は冷却器の上流側に介挿した冷媒入口側の電磁弁、１７
Ａ、 １７Ｂは出口側に介挿した′ｒ！Ｌ磁弁、１８Ａ
、 １８Ｂはバイパス管路１４Ａ、 １４Ｂに介挿した
電磁弁である。On the other hand, the refrigerant circuit including the coolers 8^ and 8B is as shown in Figure 6. In Figure 0, 12 is a condensing unit of the refrigerator, and the two coolers 8^ and 8B are connected to the condensing unit 12. 8B are connected by piping in parallel. Further, 13A and 13B are expansion valves, 14A and 14B are bypass pipes that bypass the coolers 8A and 8B and the expansion valves 13A and 13B, 15A and 15B are check valves, and 16
is a solenoid valve on the refrigerant inlet side inserted on the upstream side of the cooler, 17
A, 17B is 'r! inserted on the exit side. L solenoid valve, 18A
, 18B are solenoid valves inserted in the bypass pipes 14A, 14B.
かかる冷媒回路で、保冷運転時には第５図に示したエア
ダンパ１０を開放し、かつ第６図の電磁弁１６、１７Ａ
、 １７Ｂを開いてコンデンシングユニット１２を運転
する。これにより冷媒は実線矢印のように膨張弁１３Ａ
、 １３Ｂを通じて冷却器８Ａ、 ８８にに流れ、ここ
で蒸発してインチ冷気Ａを冷却する。In such a refrigerant circuit, during cold storage operation, the air damper 10 shown in FIG. 5 is opened, and the solenoid valves 16 and 17A shown in FIG.
, 17B is opened to operate the condensing unit 12. As a result, the refrigerant flows through the expansion valve 13A as shown by the solid line arrow.
, 13B to coolers 8A, 88 where it evaporates and cools the inch cold air A.
一方、所定の保冷運転時間が経過して除霜に移行すると
、冷却器８Ａ、 ８Ｂが片方ずつ次記に述べる液冷媒除
霜方式により交互に除霜される。ここでまず冷却器８＾
を除霜するには、エアダンパ１０（第５図）を冷却器８
＾側に倒して冷却器８Ａの通風出口を塞いだ上で、保冷
運転状態から電磁弁１６．１７Ａを閉、［磁弁１８＾を
開に切換える。これにより冷媒回路中には点線矢印で示
すように冷媒が流れるようになる。すなわちコンデンシ
ングユニット１２から送出された高温、高圧の液冷媒は
膨張弁を経由することなく、まずバイパス管＊ １４Ａ
を経て冷却器８＾に導入され、液冷媒の保育熱で冷却器
８Ａに付着している霜を融解して除霜する。またこの除
霜過程で液冷媒は過冷却状１！（温度低下）となって冷
却器８Ａより流出した後に、膨張弁１３Ｂを経て冷却器
８Ｂに入り、ここで蒸発して冷却器８Ｂを冷却運転する
。なおこの場合における冷却器８Ｂの冷凍能力は、定常
の保冷運転時と比べて冷媒が過冷却された分だけ増大す
る。これにより一方の冷却器８Ａを除霜している期間中
に、他方の冷却８Ｂで冷却運転を継続することができ、
庫内温度、商品の品温上昇を抑えることができる。On the other hand, when the predetermined cold storage operation time has elapsed and the operation shifts to defrosting, the coolers 8A and 8B are alternately defrosted one by one by the liquid refrigerant defrosting method described below. First of all, cooler 8^
To defrost the air damper 10 (Fig. 5),
After tilting it to the ^ side to block the ventilation outlet of the cooler 8A, close the solenoid valves 16 and 17A from the cold storage operation state, and switch the solenoid valve 18^ to open. This causes the refrigerant to flow in the refrigerant circuit as shown by the dotted arrow. In other words, the high-temperature, high-pressure liquid refrigerant sent out from the condensing unit 12 first passes through the bypass pipe*14A without passing through the expansion valve.
The liquid refrigerant is then introduced into the cooler 8^, and the frost adhering to the cooler 8A is melted and defrosted by the incubation heat of the liquid refrigerant. Also, during this defrosting process, the liquid refrigerant reaches a supercooled state! (temperature decrease) and flows out from the cooler 8A, it enters the cooler 8B via the expansion valve 13B, where it evaporates and operates the cooler 8B for cooling. Note that the refrigerating capacity of the cooler 8B in this case is increased by an amount corresponding to the supercooling of the refrigerant compared to that during normal cold storage operation. As a result, while one cooler 8A is being defrosted, the other cooler 8B can continue cooling operation.
It is possible to suppress the rise in internal temperature and product temperature.
また冷却器８Ａの除霜が終了すると、続いて冷却器８Ｂ
の除霜が行われる。なおこの場合の除霜は前記の手順と
同様であり、冷却器８Ｂに高温、高圧の液冷媒を導入し
液冷媒除霜を行いつつ、冷却器８＾を冷却運転させる。Furthermore, when the defrosting of the cooler 8A is completed, the cooler 8B is
defrosting is performed. Note that defrosting in this case is the same as the above-mentioned procedure, and while a high temperature, high pressure liquid refrigerant is introduced into the cooler 8B and liquid refrigerant defrosting is performed, the cooler 8^ is operated for cooling.
〔発明が解決しようとする！ＩＢ）
ところで上記した除霜方式は、ショーケースが通常の周
囲温度条件で運転している限りは、商品の品温上昇を抑
えつつ各冷却器の除霜を行うことができる効果が得られ
るが、周囲気温の低い冬期でショーケースを据付けた店
舗を閉店した夜間に先記した除霜を行うと、次記のよう
な問題が派生する。[Invention tries to solve! IB) By the way, the defrosting method described above has the effect of defrosting each cooler while suppressing the rise in product temperature as long as the showcase is operating under normal ambient temperature conditions. If the above-mentioned defrosting is performed at night when a store with a showcase installed is closed during the winter season when the ambient temperature is low, the following problems will arise.
すなわち、冬期における閉店後の夜間では、ショーケー
スの庫内照明灯が全て消灯しており、かつ周囲温度も著
しく低下するので、シボ−ケースの冷凍負荷が昼間の状
態と比べて大幅に減少する運転状態となる。このために
前述のように除霜に際して液冷媒除霜を行うと、冷媒が
除ｎ便の冷却器を通流する過程で過冷却されるために、
冷却運転側の冷却器はその時点における冷凍負荷以上の
冷凍能力を発揮して庫内を必要以上に冷却し、この結果
として商品が冷え過ぎの状態となり、生鮮商品が凍るよ
うな事態を招く、シかも翌日になって店舗が開店すれば
日中は再び周１ｍ温度が高まり、かつ庫内照明灯も点灯
するため、これらの熱を受けて夜間の間に凍った商品が
解凍されるようになる。In other words, at night after closing in winter, all the lights inside the showcase are turned off and the ambient temperature drops significantly, so the refrigeration load on the warehouse case is significantly reduced compared to during the day. It will be in operation state. For this reason, when defrosting with liquid refrigerant as mentioned above, the refrigerant is supercooled during the process of flowing through the cooler.
The cooler on the cooling operation side exerts a refrigeration capacity that exceeds the refrigeration load at that time and cools the inside of the refrigerator more than necessary, resulting in products becoming too cold and causing a situation where perishable products freeze. However, when the store opens the next day, the temperature rises again during the day, and the lights inside the refrigerator are also turned on, allowing the frozen products to thaw during the night. Become.
ところで精肉、鮮魚等は一旦凍結したものを解凍すると
、ドリップと呼ばれる肉汁が出て鮮度が急速に低下する
。このために、前記のように夜間の間に凍結したシ四−
ケース内の陳列商品が翌日に解凍するような事態になる
と、商品価値が低下するような商品の保冷管理面での不
具合を招くことになる。By the way, when meat, fresh fish, etc. are frozen and thawed, meat juices called drips are released and the freshness rapidly decreases. For this purpose, as mentioned above, the frozen four
If the products displayed in the case thaw the next day, this will lead to problems with the cold storage management of the products, which will reduce the product value.
なおショーケースは、通常の保冷運転状態で庫内温度が
冷え過ぎる状態になれば、サーモスタットの動作で冷凍
機の運転を停止するようにして庫内温度！１１ｖｉを行
っているが、第６図で述べた液冷媒除霜方式では除霜中
に冷凍機を停止すると除霜も停止してしまうため、この
除霜期間中は庫内温度調節用サーモスタットが不動作状
態にｆｌ＆：さており、この結果として前記した庫内の
冷え過ぎの運転状態が起こり得る。In addition, in the showcase, if the temperature inside the refrigerator becomes too cold during normal cold storage operation, the thermostat will operate to stop the operation of the refrigerator. 11vi, but with the liquid refrigerant defrosting method described in Figure 6, if the refrigerator is stopped during defrosting, defrosting will also stop, so during this defrosting period, the thermostat for regulating the temperature inside the refrigerator will not be activated. fl&: is in an inactive state, and as a result, the above-mentioned operating state in which the interior of the refrigerator is too cold may occur.
本発明は上記の点にかんがみ成されたものであり、先記
のように２台の冷却器の間で交互に液冷媒除霜を行う除
霜方式を併用しながら、しかもショーケースの周囲温度
が低下する冬期の夜間、閉店後等では商品の凍結を防止
しつつ冷却器の除霜を行えるようにした冷気循環形シボ
−ケースの除霜方式を提供することを目的とする。The present invention has been made in consideration of the above points, and uses a defrosting method in which liquid refrigerant defrosts are carried out alternately between two coolers as described above. To provide a defrosting method for a cold air circulation type grain case, which can defrost a cooler while preventing products from freezing at night in winter when the temperature decreases, after the store is closed, etc.
上記ｍｌ！Ｊ！を解決するために、本発明の除霜方式に
おいては、庫内の冷気循環路に並置した２台の冷却器に
対し、通常の周囲温度条件の運転中における除霜時には
片方ずつ交互に液冷媒除霜を行い、一方、冬期の閉店後
の夜間等に除霜する場合には、除霜に際してショーケー
スの庫内照明灯の消灯。The above ml! J! In order to solve this problem, in the defrosting method of the present invention, liquid refrigerant is alternately applied to two coolers placed in parallel in the cold air circulation path inside the refrigerator during defrosting during operation under normal ambient temperature conditions. On the other hand, if defrosting is carried out at night after the store is closed in the winter, the lighting inside the showcase should be turned off during defrosting.
周囲外気温低下の条件で各冷却器への冷媒供給を停止し
、冷却器の除霜を液冷媒除霜からオフサイクル除霜に切
換えて除霜を行うものとする。Defrosting is performed by stopping the refrigerant supply to each cooler under conditions of a decrease in the ambient outside temperature, and switching the defrosting of the cooler from liquid refrigerant defrosting to off-cycle defrosting.
また、庫内にインチ、アウタ冷気循環路を存して内外２
層のエアカーテンを吹出し形成するシボ−ケースに対し
ては、通常時は前記と同様に２台の冷却器に対して交互
に液冷媒除霜を行うとともに、冬期の閉店後の夜間等に
除霜する場合には、除霜に際してショーケースの庫内照
明灯の消灯。In addition, there is an inch and an outer cold air circulation path inside the refrigerator, and there are two inner and outer cold air circulation paths.
Normally, liquid refrigerant defrost is applied to the two coolers alternately in the same way as described above, and defrosting is performed at night after the store is closed in the winter, etc. for the case where a layered air curtain is blown out. In case of frost, turn off the interior lighting of the showcase during defrosting.
周囲外気温低下の条件で各冷却器への冷媒供給を停止す
るとともに、アウタ冷気循環路のファンを逆転し、冷却
器の除霜を前記の液冷媒除霜から逆転ファンにより外気
を導入する空気除霜に切換えるようにする。When the ambient outside temperature drops, the refrigerant supply to each cooler is stopped, and the fan in the outer cold air circulation path is reversed to defrost the cooler. Switch to defrosting.
上記において、除霜を液冷媒除霜からオフサイクル除霜
、ないし空気除霜に切換えるための手段としては、庫内
照明灯の照明スイッチの点滅に連動動作するリレー、お
よびショーケースの周囲外気温が設定温度以下に低下し
た条件で動作する外気温サーモスタットを備え、これら
の動作信号を基に冷却器を含む冷凍機の冷媒回路に介挿
した電磁弁の開閉制御、並びにアウタファンの正、逆転
側柵を行うようにする。In the above, the means for switching the defrosting from liquid refrigerant defrosting to off-cycle defrosting or air defrosting include a relay that operates in conjunction with the blinking of the light switch of the interior light, and the ambient temperature of the showcase. Equipped with an outside temperature thermostat that operates when the outside temperature drops below the set temperature, and based on these operating signals, it controls the opening and closing of the solenoid valve inserted in the refrigerant circuit of the refrigerator including the cooler, as well as forward and reverse rotation of the outer fan. Make sure to install side fences.
ここで、周囲温度が低下している冬期の夜間。Here, at night in winter when the ambient temperature is dropping.
閉店時に除霜を行う際に、前記のように照明灯の消灯２
周囲外気温低下の条件で除霜をオフサイクル除霜に切換
えることより、冷却器への冷媒供給を停止した非冷却状
態で冷気循環路を通風する循環空気で冷却器の表面に付
着しいてる霜が除霜されるようになる。したがってＩＫ
６図で述べた液冷媒除霜方式で問題となっていた冷媒の
過冷却に起因する庫内の冷え過ぎを防止しつつ除霜を行
うことができる。When defrosting at closing time, turn off the lighting 2 as described above.
By switching defrosting to off-cycle defrosting when the ambient temperature drops, the refrigerant supply to the cooler is stopped and the circulating air that passes through the cold air circulation path is used to remove frost that forms on the surface of the cooler. will be defrosted. Therefore IK
Defrosting can be performed while preventing the inside of the refrigerator from becoming too cold due to overcooling of the refrigerant, which was a problem with the liquid refrigerant defrosting method described in FIG.
また、特にＩＩ冷冷気循環クシヨーケース対しては、各
冷却器への冷媒供給を停止するとともに、さらにアウタ
ファンを逆転して空気除霜に切換えることにより、アウ
タ冷気Ｗｉ環路の冷気吹出口を通じてショーケース周囲
より吸い込まれた外気がアウタ冷気循環路を逆方向に巡
回した後に、その冷気吸込口より隣接するインナ冷気循
環路内に取り込まれて冷却器を通風するようになる。し
たがって前記のオフサイクル除霜と同様に庫内の冷え過
ぎ防止を図りつつ、さらに外気の保有熱を有効に活用し
て冷却器を効果的に早期に除霜することができるように
なる。In addition, especially for the II cold air circulation case, by stopping the refrigerant supply to each cooler and also reversing the outer fan and switching to air defrosting, the cold air outlet of the outer cold air Wi loop can be used to cool the air. After the outside air sucked in from around the case circulates in the outer cold air circulation path in the opposite direction, it is taken into the adjacent inner cold air circulation path through the cold air suction port to ventilate the cooler. Therefore, like the above-described off-cycle defrosting, it is possible to prevent the interior of the refrigerator from becoming too cold, and to effectively utilize the heat retained in the outside air to effectively defrost the cooler at an early stage.
第１図ないし第４図は本発明の実施例を示すものであり
、第１図は冷却器の除霜を液冷媒除霜／オフサイクル除
霜に切換える除霜制御回路図、第２図は第１図の応用実
施例として複数台のショーケースを同一場所に連ねて裾
付けた場合の除霜制御回路系統図、第３図は冷却器の除
霜を液冷媒除ｎ／空気除霜に切換える２層エアカーテン
式冷気循環形シッーケースに対する除霜制御回路図、第
４図は第３図の方式による空気除霜時における庫内の通
風状態図であり、第１図〜第４図において第５図、第６
図に対応する同一部分には同じ符号が付しである。Figures 1 to 4 show embodiments of the present invention, with Figure 1 being a defrosting control circuit diagram for switching the defrosting of the cooler to liquid refrigerant defrosting/off cycle defrosting, and Figure 2 being a defrosting control circuit diagram for switching the defrosting of the cooler to liquid refrigerant defrosting/off-cycle defrosting. As an applied example of Fig. 1, a defrosting control circuit system diagram is shown when multiple showcases are connected in the same place. Fig. 3 shows the defrosting of the cooler by liquid refrigerant defrosting/air defrosting. Fig. 4 is a defrosting control circuit diagram for a switching two-layer air curtain type cold air circulation type air case. Figure 5, 6th
Identical parts corresponding to the figures are given the same reference numerals.
まず第１図において、１９はショーケースに組み込まれ
た除霜コントローラであり、該コントローラ１９の内部
にはタイマ制御等によりショーケースを保冷運転から除
霜に切換えた上で第６図に示した冷媒回路の各電磁弁１
６．１７Ａ、 １７Ｂ、 １８Ａ、 １８Ｂを開閉制御
する電磁弁制御回路２０を備えている。また２１は庫内
照明灯１１の電源回路に介挿した照明スイッチ、２２は
照明スイッチに連動して照明灯１１の点滅を検出する補
助リレー（ＸＩ） 、２３はショーケースの周囲温度が
設定温度（１０〜１５°Ｃ程度）以下に低下した際に動
作する外気温サーモスタット、２４はその補助リレー（
ｘ２）であり、各補助リレー２２．２４の動作信号を前
記したコントローラ１９の電磁弁制御回路２０へ入力し
て除霜を液冷媒除霜からオフサイクル除霜へ切換えるよ
うに各リレー接点が電磁弁制御回路に組み込まれている
。First, in FIG. 1, reference numeral 19 is a defrosting controller built into the showcase. Inside the controller 19, the controller 19 switches the showcase from cold storage operation to defrosting mode using timer control, etc., as shown in FIG. 6. Each solenoid valve 1 in the refrigerant circuit
6. Equipped with a solenoid valve control circuit 20 that controls opening and closing of 17A, 17B, 18A, and 18B. In addition, 21 is a lighting switch inserted in the power supply circuit of the interior lighting lamp 11, 22 is an auxiliary relay (XI) that detects blinking of the lighting lamp 11 in conjunction with the lighting switch, and 23 is a lighting switch that is set to the ambient temperature of the showcase. 24 is the auxiliary relay (
x2), and each relay contact is connected to an electromagnetic valve so that the operation signal of each auxiliary relay 22, 24 is input to the solenoid valve control circuit 20 of the controller 19 described above to switch defrosting from liquid refrigerant defrosting to off-cycle defrosting. Built into the valve control circuit.
次に上記によるショーケースの除霜動作に付いて説明す
る。まず通常の周囲温度条件で、かつ庫内照明灯１１を
点灯してショーケースを運転している状態では、コント
ローラ１９に組み込まれたタイマの制御により、第６図
で述べたように各冷却器８＾、 ８Ｂが所定時間の周期
で交互に液冷媒除霜方式で除霜される。Next, the defrosting operation of the showcase as described above will be explained. First, under normal ambient temperature conditions and when the showcase is operating with the interior lighting 11 turned on, each cooler is controlled by a timer built into the controller 19, as described in FIG. 8^ and 8B are defrosted alternately at predetermined time intervals using a liquid refrigerant defrosting method.
一方、冬期の夜間、閉店時には周囲温度が低下し、かつ
照明灯１１も消灯している。この状態になると第１図の
補助リレー２２．２４を介してコントローラ１９に照明
灯の消灯検出信号、並びに外気温低下検出信号が入力さ
れる。この条件下でショーケースが保冷運転から除霜に
移行すると、前記信号を基にコントローラ１９は、第６
図に示した各ｔｍ弁のうち、電磁弁１６．１８＾、１８
Ｂを閉、電磁弁１７Ａ。On the other hand, at night in winter, when the store is closed, the ambient temperature drops and the lighting 11 is also turned off. When this state is reached, an illumination light extinguishment detection signal and an outside temperature drop detection signal are input to the controller 19 via the auxiliary relays 22 and 24 shown in FIG. When the showcase shifts from cold preservation operation to defrosting under this condition, the controller 19 operates the sixth
Among the tm valves shown in the figure, solenoid valves 16, 18^, 18
Close B, solenoid valve 17A.
１７Ｂを開の状態に切換える。したがって保冷運転時に
冷媒が冷却器８Ａ、 ８Ｂを通流していた状態から、各
冷却器への冷媒流入が遮断され、同時に冷却器内に残留
しいてる冷媒は戻り管路を通じてコンデンシングユニッ
ト１２に回収された後、コンデンシングユニット１２は
圧縮機に付属する低圧スイッチの動作で運転停止となる
。Switch 17B to the open state. Therefore, from the state in which refrigerant was flowing through the coolers 8A and 8B during cold storage operation, the flow of refrigerant to each cooler is cut off, and at the same time, the refrigerant remaining in the cooler is recovered to the condensing unit 12 through the return pipe. After that, the condensing unit 12 is shut down by the operation of a low pressure switch attached to the compressor.
またこの状態になると冷却器８Ａ、 ８Ｂへの冷媒供給
が遮断されるとともに、各冷却器の内部には冷媒が無く
なるので冷却が行われず、一方では第５図に示した冷気
循環路５にファン７による空気循環送風が継続している
。したがって冷却器８Ａ、 ８Ｂはオフサイクル除霜の
状態となり、これにより冷却器の温度がここを通風する
空気の温度に近づき、そして空気温度がＯ′Ｃ以上にな
れば、冷却器の表面に付着している霜が融解除去される
ようになる。In addition, in this state, the refrigerant supply to the coolers 8A and 8B is cut off, and there is no refrigerant inside each cooler, so cooling is not performed.On the other hand, a fan is installed in the cold air circulation path 5 shown in FIG. Air circulation and blowing by No. 7 continues. Therefore, the coolers 8A and 8B are in a state of off-cycle defrosting, and as a result, the temperature of the coolers approaches the temperature of the air ventilated through them, and if the air temperature exceeds O'C, deposits on the surface of the coolers will be removed. The frost that is present will now melt and be removed.
なお除霜が進行して冷却器の温度があらかじめ設定した
除霜終了温度（５°Ｃ程度）まで上昇する状態になれば
、除霜終了サーモスタットの信号で除霜が解除されてシ
ョーケースは再び保冷運転に戻る。If defrosting progresses and the temperature of the cooler rises to the preset defrost end temperature (approximately 5°C), the defrost will be canceled by the signal from the defrost end thermostat and the showcase will open again. Return to cold storage operation.
第２図は同一場所に複数台のショーケースを連結して据
付けた場合の除霜制御回路の系統図を示したものであり
、１．ｎ、ＩＩＩで示す各基のショーケース毎に装備し
たコントローラ１９に対し、１台の外気温サーモスタッ
ト２３を共通に接続したものである。これにより除霜制
御回路が簡略となり、かつ各基のショーケースＩ〜■を
同期してオフサイクル除霜に切換えることが可能となる
。Figure 2 shows a system diagram of the defrosting control circuit when multiple showcases are connected and installed in the same location.1. One outside temperature thermostat 23 is commonly connected to the controller 19 installed in each showcase shown by n and III. This simplifies the defrosting control circuit, and allows each of the showcases I to (2) to be switched to off-cycle defrosting in synchronization.
次に第３図、第４図に２層冷気循環形シッーケースを対
象とした本発明除霜方式の別な実施例を示す、まず第３
図の除霜制御回路において、コントローラ１９には先記
実施例（第１図）で述べた電磁弁制御回路２０の他に、
第４図におけるアウタファン９を正転、逆転に切換え制
御するファン制御回路２５を備えており、ここに電磁弁
制御回路２ｏと同様に照明灯回路に介挿した補助リレー
２２．および外気温サーモスタット２３の回路に介挿し
た補助リレー２４の各リレー接点が組み込まれている。Next, Fig. 3 and Fig. 4 show another embodiment of the defrosting method of the present invention for a two-layer cold air circulation type case.
In the defrosting control circuit shown in the figure, the controller 19 includes, in addition to the solenoid valve control circuit 20 described in the previous embodiment (FIG. 1).
It is equipped with a fan control circuit 25 that switches and controls the outer fan 9 in FIG. 4 between normal rotation and reverse rotation, and an auxiliary relay 22. The relay contacts of an auxiliary relay 24 inserted into the circuit of the outside temperature thermostat 23 are also incorporated.
かかる除霜制御回路で、まず通常の周囲温度条件で、か
つ庫内照明灯１１を点灯してショーケースを運転してい
る状態では、第１図の実施例と同様にコントローラ１９
に組み込まれたタイマの制御により、第６図で述べたよ
うに各冷却器８Ａ、 ８Ｂが所定時間の周期で交互に液
冷媒除霜方式で除霜される。In this defrosting control circuit, when the showcase is operated under normal ambient temperature conditions and with the interior lighting 11 turned on, the controller 19 is activated as in the embodiment shown in FIG.
As described in FIG. 6, each of the coolers 8A and 8B is defrosted by the liquid refrigerant defrosting method alternately at a predetermined period of time under the control of a timer built into the cooler.
一方、周囲温度が低下し、かつ照明灯１１が消灯してい
る冬期の夜間、閉店状態で、ショーケースが保冷運転か
ら除霜に移行すると、第１図の実施例と同様に電磁弁制
御回路２０が冷却器８＾、 ８Ｂへの冷媒供給を停止す
るように各電磁弁を制御するとともに、同時にファン制
御回路２５により庫内のアウタ冷気循環路６に設置した
アウタファン９を正転から逆転に切換え、次記のように
空気除霜を開始する。On the other hand, when the showcase shifts from cold preservation operation to defrosting operation at night in winter when the ambient temperature is low and the illumination lights 11 are turned off, the solenoid valve control circuit 20 controls each electromagnetic valve to stop the refrigerant supply to the coolers 8^, 8B, and at the same time, the fan control circuit 25 changes the outer fan 9 installed in the outer cold air circulation path 6 inside the refrigerator from normal rotation to reverse rotation. and start air defrosting as described below.
すなわち、空気除霜の状態になると庫内での通風状態が
第４図で示すように、アウタ冷気循環路６には矢印Ｂｏ
で示すように第５図に示した保冷運転時の冷気流Ｂと逆
向きに空気が通風する。したがってケース本体１の前面
側でインナ冷気循環路５の冷気吹出口から吹き出た空気
流ＡＯはケース本体１の前面にエアカーテンを吹出し形
成しつつ、その一部はショーケース周囲から吸い込む外
気と合流してアウタ冷気循環路６の冷気吹出口より吸い
込まれ、アウタ冷気循環路６内を巡回した後にその冷気
吸込口より一旦吹出し、さらにケース本体１の前面を流
下するインナ冷気循環路５側のエアカーテンと合流して
インナ冷気循環路５に吸い込まれるように通風する。つ
まりケース本体１の前面にエアカーテンを吹出し形成し
つつ、ショーケースの周囲から吸い込んだ外気がアウタ
冷気循環路６を巡回した後にエアカーテンと合流してイ
ンナ冷気循環路５へ積極的に取り込まれるようになる。That is, when the air defrost condition is reached, the ventilation condition inside the refrigerator changes as shown in FIG.
As shown in FIG. 5, air flows in the opposite direction to the cold air flow B during the cold storage operation shown in FIG. Therefore, the air flow AO blown out from the cold air outlet of the inner cold air circulation path 5 on the front side of the case body 1 blows out and forms an air curtain on the front side of the case body 1, and a part of it merges with the outside air sucked in from around the showcase. The air on the inner cold air circulation path 5 side is sucked in from the cold air outlet of the outer cold air circulation path 6, circulates within the outer cold air circulation path 6, is once blown out of the cold air suction port, and then flows down the front surface of the case body 1. Ventilation is carried out so that it merges with the curtain and is sucked into the inner cold air circulation path 5. In other words, while forming an air curtain on the front surface of the case body 1, outside air is drawn in from around the showcase, circulates through the outer cold air circulation path 6, merges with the air curtain, and is actively taken into the inner cold air circulation path 5. It becomes like this.
しかも外気温は庫内の冷却温度よりも高く、したがって
外気の保有熱により冷却器８＾、 ８Ｂに付着している
霜は早期に除霜されるようになる。またこの除霜期間中
は不完全ながらケース本体１の前面にはエアカーテンが
吹出し形成されるので、商品陳列室４内への外気熱侵入
が阻止され、商品の品温上昇を抑えることができる。Furthermore, the outside temperature is higher than the cooling temperature inside the refrigerator, so the frost adhering to the coolers 8^ and 8B is quickly defrosted due to the retained heat of the outside air. Also, during this defrosting period, an air curtain is blown out on the front of the case body 1, although it is incomplete, so that outside heat is prevented from entering the product display room 4, and the rise in product temperature can be suppressed. .
本発明の除霜方式は、以上説明したように構成されてい
るので、次記の効果を奏する。Since the defrosting method of the present invention is configured as described above, it achieves the following effects.
すなわち、冷凍負荷の減少する冬期の夜間、閉店後の運
転状態で除霜を行う際には、通常の周囲温度条件で実施
する液冷媒除霜からオフサイクル除霜、ないしアウタフ
ァンの逆転による空気除霜に切換えることにより、この
条件での液冷媒除霜で問題となっていた冷媒の過冷却に
起因する庫内の冷え過ぎ、商品凍結の問題を解消して、
商品の凍結防止を図りつつ冷却器に付着している霜を良
好に除霜することができ、これによって生鮮食品等の商
品品質維持に優れた効果を発揮することができる。In other words, when defrosting is performed at night in the winter when the refrigeration load is reduced, or when the store is in operation after the store is closed, it is necessary to switch from liquid refrigerant defrosting performed under normal ambient temperature conditions to off-cycle defrosting or air defrosting by reversing the outer fan. By switching to defrosting, the problem of liquid refrigerant defrosting under these conditions, which was caused by overcooling of the refrigerant and causing the interior to become too cold and products to freeze, was resolved.
It is possible to effectively defrost the frost adhering to the cooler while preventing products from freezing, thereby achieving an excellent effect in maintaining the quality of products such as fresh foods.
第１図ないし第４図は本発明の実施例を示すものであり
、第１図は冷却器の除霜を液冷媒除霜／オフサイクル除
霜に切換える除霜制御回路図、第２図は第１図の応用実
施例として複数台のショーケースを同一場所に連ねて据
付けた場合の除霜制御回路系統図、第３図は２層エアカ
ーテン式冷気循環形シゴーケースを対象に冷却器の除霜
を液冷媒除霜／空気除霜に切換える除霜制御回路図、第
４図は第３図の方式による空気除霜時における庫内の通
風状態図、第５図は保冷運転状態の庫内通風状態を表し
た冷気循環形ショーケースの構成断面図、第６図は従来
より実施されている液冷媒除霜方式を示す冷凍機の冷媒
回路図である。各図において、
１ニジチーケースのケース本体、５：インナ冷気循環路
、６：アウタ冷気循環路、７：インナファン、８Ａ、８
８：冷却器、９：アウタファン、１１：庫内照明灯、１
２：冷凍機のコンデンシングユニット、１３Ａ、 １３
８：膨張弁、１４Ａ、 １４Ｂ：バイパス管路、ｉ６．
１７Ａ、 １７Ｂ、 １８Ａ、 １８Ｂ：電磁弁、１９
：コントローラ、２０：１１Ｍ１弁制御回路、２１：照
明スイッチ、２２．２４：補助リレー、２３：外気温サ
ーモスタット、２５：アウタファン制御回路。
第２図
第４図Figures 1 to 4 show embodiments of the present invention, with Figure 1 being a defrosting control circuit diagram for switching the defrosting of the cooler to liquid refrigerant defrosting/off cycle defrosting, and Figure 2 being a defrosting control circuit diagram for switching the defrosting of the cooler to liquid refrigerant defrosting/off-cycle defrosting. As an applied example of Fig. 1, a defrosting control circuit system diagram is shown when multiple showcases are installed in the same location. A defrosting control circuit diagram that switches the frost to liquid refrigerant defrosting/air defrosting, Figure 4 is a diagram of the ventilation inside the refrigerator during air defrosting using the method shown in Figure 3, and Figure 5 is the interior of the refrigerator during cold storage operation. FIG. 6 is a cross-sectional view of the configuration of a cold air circulation type showcase showing a ventilation state, and a refrigerant circuit diagram of a refrigerator showing a conventional liquid refrigerant defrosting system. In each figure, 1 case body of the rainbow case, 5: inner cold air circulation path, 6: outer cold air circulation path, 7: inner fan, 8A, 8
8: Cooler, 9: Outer fan, 11: Interior lighting, 1
2: Refrigerator condensing unit, 13A, 13
8: expansion valve, 14A, 14B: bypass pipe, i6.
17A, 17B, 18A, 18B: Solenoid valve, 19
: Controller, 20: 11M1 valve control circuit, 21: Lighting switch, 22.24: Auxiliary relay, 23: Outside temperature thermostat, 25: Outer fan control circuit. Figure 2 Figure 4
Claims (1)
の冷却器を並置配備し、かつ各冷却器の除霜を周期的に
片方ずつ交互に行うとともに、除霜時には除霜側の冷却
器に高温、高圧の液冷媒を直接導入して液冷媒除霜を行
いつつ、該冷却器より出た過冷却の冷媒を他方の冷却器
に供給して冷却運転を継続するようにした冷気循環形シ
ョーケースにおいて、除霜に際して庫内照明灯の消灯、
周囲外気温低下の条件で各冷却器への冷媒供給を停止し
、冷却器の除霜を前記の液冷媒除霜からオフサイクル除
霜に切換えるようにしたことを特徴とする冷気循環形シ
ョーケースの除霜方式。 ２）庫内にインナ、アウタ冷気循環路を有して内外２層
のエアカーテンを吹出し形成するショーケースに対して
そのインナ冷気循環路内に２台の冷却器を並置配備し、
かつ各冷却器の除霜を周期的に片方ずつ交互に行うとと
もに、除霜時には除霜側の冷却器に高温、高圧の液冷媒
を直接導入して液冷媒除霜を行いつつ、該冷却器より出
た過冷却の冷媒を他方の冷却器に供給して冷却運転を継
続するようにした冷気循環形ショーケースにおいて、除
霜に際してショーケースの庫内照明灯の消灯、周囲外気
温低下の条件で各冷却器への冷媒供給を停止するととも
に、アウタ冷気循環路のファンを逆転し、冷却器の除霜
を前記の液冷媒除霜から逆転ファンにより外気を導入す
る空気除霜に切換えるようにしたことを特徴とする冷気
循環形ショーケースの除霜方式。[Scope of Claims] 1) Two coolers are arranged side by side together with fans in the cold air circulation path of the showcase, and each cooler is defrosted periodically one by one. While defrosting the liquid refrigerant by directly introducing a high-temperature, high-pressure liquid refrigerant into the frost-side cooler, the supercooled refrigerant discharged from the cooler is supplied to the other cooler to continue cooling operation. In the cold air circulation type showcase, when defrosting, the interior lights are turned off and
A cold air circulation type showcase characterized in that the refrigerant supply to each cooler is stopped under conditions of a drop in ambient outside temperature, and the defrosting of the coolers is switched from the liquid refrigerant defrosting to off-cycle defrosting. Defrosting method. 2) For a showcase that has an inner and an outer cold air circulation path in the refrigerator and forms a two-layer air curtain inside and outside, two coolers are placed side by side in the inner cold air circulation path,
In addition, each cooler is periodically defrosted one by one, and at the time of defrosting, high-temperature, high-pressure liquid refrigerant is directly introduced into the cooler on the defrosting side to perform liquid refrigerant defrosting. In a cold air circulation type showcase that supplies supercooled refrigerant from one cooler to the other cooler to continue cooling operation, the conditions for turning off the interior lights of the showcase and lowering the ambient outside temperature during defrosting. At the same time, the refrigerant supply to each cooler is stopped, the fan in the outer cold air circulation path is reversed, and the defrosting of the cooler is switched from the liquid refrigerant defrosting described above to air defrosting in which outside air is introduced by a reversing fan. A defrosting method for cold air circulation type showcases.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63120353A JPH0726782B2 (en) | 1988-05-17 | 1988-05-17 | Defroster for cold air circulation type showcase |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63120353A JPH0726782B2 (en) | 1988-05-17 | 1988-05-17 | Defroster for cold air circulation type showcase |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01291083A true JPH01291083A (en) | 1989-11-22 |
| JPH0726782B2 JPH0726782B2 (en) | 1995-03-29 |
Family
ID=14784118
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63120353A Expired - Lifetime JPH0726782B2 (en) | 1988-05-17 | 1988-05-17 | Defroster for cold air circulation type showcase |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0726782B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03177773A (en) * | 1989-12-05 | 1991-08-01 | Fuji Electric Co Ltd | Defrosting of cold air circulation type open showcase |
| JP2007024443A (en) * | 2005-07-20 | 2007-02-01 | Sanyo Electric Co Ltd | Air conditioner and control method of air conditioner |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5034873U (en) * | 1973-07-25 | 1975-04-14 | ||
| JPS57108576A (en) * | 1980-12-26 | 1982-07-06 | Fuji Electric Co Ltd | Refrigerated showcase with front door |
| JPS60191171A (en) * | 1984-03-13 | 1985-09-28 | サンデン株式会社 | Showcase |
| JPS6115062A (en) * | 1984-06-29 | 1986-01-23 | 富士電機株式会社 | Defrostation system of open showcase |
-
1988
- 1988-05-17 JP JP63120353A patent/JPH0726782B2/en not_active Expired - Lifetime
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5034873U (en) * | 1973-07-25 | 1975-04-14 | ||
| JPS57108576A (en) * | 1980-12-26 | 1982-07-06 | Fuji Electric Co Ltd | Refrigerated showcase with front door |
| JPS60191171A (en) * | 1984-03-13 | 1985-09-28 | サンデン株式会社 | Showcase |
| JPS6115062A (en) * | 1984-06-29 | 1986-01-23 | 富士電機株式会社 | Defrostation system of open showcase |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03177773A (en) * | 1989-12-05 | 1991-08-01 | Fuji Electric Co Ltd | Defrosting of cold air circulation type open showcase |
| JP2007024443A (en) * | 2005-07-20 | 2007-02-01 | Sanyo Electric Co Ltd | Air conditioner and control method of air conditioner |
| JP4703299B2 (en) * | 2005-07-20 | 2011-06-15 | 三洋電機株式会社 | Air conditioner |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0726782B2 (en) | 1995-03-29 |
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