JP3430160B2

JP3430160B2 - refrigerator

Info

Publication number: JP3430160B2
Application number: JP2001141250A
Authority: JP
Inventors: 哲哉斎藤; 義人木村; 泰樹浜野
Original assignee: 松下冷機株式会社
Priority date: 2001-05-11
Filing date: 2001-05-11
Publication date: 2003-07-28
Anticipated expiration: 2019-02-09
Also published as: JP2001355955A

Description

【発明の詳細な説明】【０００１】【発明の属する技術分野】本発明は、冷凍室と冷蔵室と
を互いに独立に冷却を行う冷却システムの冷媒量削減と
高効率化および安全性向上に関するものである。【０００２】【従来の技術】図1３に従来の冷却サイクル並びに冷蔵
庫の一例として、特公昭６２−２２３９６号公報に開示
されている冷蔵庫の概略図を示す。【０００３】１は一定速の圧縮機、２は凝縮器、３は冷
蔵室４内に配設された第一の蒸発器であり、５は、冷凍
室６内に配設された第二の蒸発器である。【０００４】７は冷蔵室冷却用である第一の蒸発器３の
冷媒回路上流側に配設された第一のキャピラリであり、
８は冷凍室冷却用である第二の蒸発器５の冷媒回路上流
側に配設された第二のキャピラリであり、９は冷凍室冷
却用の第二の蒸発器５の下流側に設けた逆止弁である。【０００５】１０は第一の蒸発器３の冷媒回路下流側に
配設された第一の開閉弁であり、１１は第二のキャピラ
リ８の冷媒回路上流側に設けられた第二の開閉弁であ
る。【０００６】以上のように構成された従来例の冷蔵庫に
ついて、以下その動作を説明する。【０００７】冷凍サイクルの運転は以下のように行われ
る。まず圧縮機１により圧縮された冷媒が凝縮器２で凝
縮液化される。凝縮された冷媒は第一のキャピラリ７も
しくは第二のキャピラリ８で減圧されて、それぞれ第一
の蒸発器３，第二の蒸発器５へ流入、蒸発気化された
後、再び圧縮機１へと吸入される。【０００８】冷媒が蒸発気化することにより比較的低温
となった第一の蒸発器３，第二の蒸発器５と冷蔵室４，
冷凍室６の空気が熱交換することにより各室が冷却され
る。【０００９】冷蔵庫の冷却運転は図示しない各室の温度
検知手段と制御手段により以下のように行われる。【００１０】冷蔵室４，冷凍室６の各温度検知手段が所
定値以上の温度上昇を検知すると圧縮機１が起動し、冷
凍サイクルの運転が行われる。冷蔵室４の温度検知手段
が所定値以下となるまで第一の開閉弁１０が開放とな
り、第二の開閉弁１１は閉止となる。【００１１】これにより冷媒は第二の蒸発器５には流入
することなく、第一の蒸発器３へのみ流れる。このとき
の冷凍サイクルの蒸発温度の設定は、冷蔵室４の温度設
定が５℃程度に対して−５〜０℃であり、通常の−３０
〜−２５℃の蒸発温度に対して２〜２．５倍の成績係数
で圧縮機の運転が可能である。【００１２】冷蔵室４が冷却されて温度が低下し、温度
検知手段が所定値以下を検知すると、第一の開閉弁１０
が閉止し、第二の開閉弁１１が開放となる。【００１３】これにより冷媒は第二の蒸発器５へと流入
し、冷凍室６の冷却が行われる。このときの冷凍サイク
ルの蒸発温度は冷凍室の温度設定が−１８℃程度に対し
通常の蒸発温度で冷却される。【００１４】以上のように冷蔵室４と冷凍室６とを蒸発
器への冷媒供給時間を分配して、交互に繰り返し冷却す
るので、冷蔵室４冷却時は独立的に冷媒を第一の蒸発器
へと循環させることで低圧圧力調整弁が不要で高蒸発温
度（−５〜０℃）が可能であり、圧縮機１の圧縮比を小
さくでき、高い成績係数で運転を行い効率化を図るもの
である。【００１５】さらに、逆止弁９は冷蔵室４冷却中の蒸発
温度が高いので、第二の蒸発器５に冷媒が流れ込むを防
止するものである。【００１６】また、冷凍室６の冷却を行う場合、冷蔵室
４の冷却中に比較して冷媒量が少なくてすむので、通常
は冷媒量過多となる。しかしながら第一の開閉弁１０が
第一の蒸発器３の下流側に設けてあり、これを閉止する
ので第一の蒸発器３に冷媒を溜め込むことが可能であ
り、冷媒量調節ができる。【００１７】【発明が解決しようとする課題】上記従来の冷蔵庫にあ
っては、冷蔵室４と冷凍室６とを蒸発器への冷媒供給時
間を分配して、交互に繰り返し冷却することで冷蔵室４
冷却時の冷凍サイクルを圧縮機１の成績係数がよい比較
的高蒸発温度（−５〜０℃）で運転することを可能とし
ている。【００１８】しかし、冷蔵室４冷却時において冷凍室６
の温度が例えば約−１８℃と低いために冷凍室６内に配
設された第二の蒸発器５の圧力は低圧となるので、第二
の蒸発器５に滞留した冷媒は第二の蒸発器５から流出し
にくい。その結果、第一の蒸発器３に十分な冷媒が供給
されず、冷媒循環量不足となり効率が低下することとな
る。【００１９】上記の要因により、必要な冷媒量が増大
し、可燃性冷媒を用いる場合には冷媒漏洩時の危険性が
大きく問題がある。【００２０】本発明は、以上のような従来の課題を解決
するもので、冷蔵室と冷凍室の冷却を切り替えて行う冷
却システムの冷媒量削減と効率向上を行うことで、省エ
ネルギーが可能である冷蔵庫を提供することを目的とす
る。【００２１】【課題を解決するための手段】この目的を達成するため
に本発明の冷蔵庫は、冷蔵室と冷凍室とで構成された冷
蔵庫箱体と、前記冷蔵室に第一の蒸発器を、前記冷凍室
に第二の蒸発器を配設し、圧縮機と、凝縮器と、第一の
キャピラリと、前記第一の蒸発器と、第二のキャピラリ
と、前記第二の蒸発器、前記第一の蒸発器または前記第
二の蒸発器への流路を交互に開閉し且つ双方への流路を
閉止可能な流路制御手段とよりなる冷凍サイクルと、前
記冷凍サイクルに封入された可燃性自然冷媒とを備え、
前記圧縮機と前記凝縮器と前記第一のキャピラリと前記
第一の蒸発器とで閉ループを形成するとともに、前記第
一のキャピラリと前記第一の蒸発器に並列となるように
前記第二のキャピラリと前記第二の蒸発器とを接続し、
前記流路制御手段により冷媒の流れを切り替えるもので
あり、前記第二の蒸発器の配管温度を検出する温度検知
手段を設け、冷凍室冷却から冷蔵室冷却へ切り替わる時
に、所定時間前記流路制御手段を閉止した状態で前記圧
縮機を運転した後、前記温度検知手段が所定温度以下を
検出すると前記流路制御手段を前記第一の蒸発器側に開
放して冷蔵室冷却を開始することを特徴とする。【００２２】この発明によれば、冷凍室冷却終了後、流
路制御手段を所定時間閉止し冷媒の流れを完全に遮断し
た状態で圧縮機を運転させることにより圧縮機内の圧力
が通常運転時と比較して低圧となるので、第二の蒸発器
内に滞留していた冷媒を第二の蒸発器から圧縮機側へ追
い出すことが可能となる。【００２３】その結果、冷蔵室冷却に切り替わった時に
冷蔵室を冷却するのに十分な冷媒が第一の蒸発器に供給
されるので冷媒循環量不足にならず、効率よく冷蔵室を
冷却することが可能となる。また、過度の圧力低下を防
止でき、圧縮機への負荷を軽減できる。【００２４】【００２５】【００２６】【００２７】また、冷媒を効率よく利用することができ
るので冷媒量を削減でき、可燃性冷媒の漏洩時の危険性
を小さくすることが可能となる。【００２８】【発明の実施の形態】本発明の請求項１に記載の発明
は、冷蔵室と冷凍室とで構成された冷蔵庫箱体と、前記
冷蔵室に第一の蒸発器を、前記冷凍室に第二の蒸発器を
配設し、圧縮機と、凝縮器と、第一のキャピラリと、前
記第一の蒸発器と、第二のキャピラリと、前記第二の蒸
発器、前記第一の蒸発器または前記第二の蒸発器への流
路を交互に開閉し且つ双方への流路を閉止可能な流路制
御手段とよりなる冷凍サイクルと、前記冷凍サイクルに
封入された可燃性自然冷媒とを備え、前記圧縮機と前記
凝縮器と前記第一のキャピラリと前記第一の蒸発器とで
閉ループを形成するとともに、前記第一のキャピラリと
前記第一の蒸発器に並列となるように前記第二のキャピ
ラリと前記第二の蒸発器とを接続し、前記流路制御手段
により冷媒の流れを切り替えるものであり、前記第二の
蒸発器の配管温度を検出する温度検知手段を設け、冷凍
室冷却から冷蔵室冷却へ切り替わる時に、所定時間前記
流路制御手段を閉止した状態で前記圧縮機を運転した
後、前記温度検知手段が所定温度以下を検出すると前記
流路制御手段を前記第一の蒸発器側に開放して冷蔵室冷
却を開始するものであり、冷凍室冷却終了後、流路制御
手段を所定時間閉止し冷媒の流れを完全に遮断した状態
で圧縮機を運転させることにより圧縮機内の圧力が通常
運転時と比較して低圧となるので、第二の蒸発器内に滞
留していた冷媒を第二の蒸発器から圧縮機側へ追い出す
ことが可能となる。その結果、冷蔵室冷却に切り替わっ
た時に冷蔵室を冷却するのに十分な冷媒が第一の蒸発器
に供給されるので冷媒循環量不足にならず、効率よく冷
蔵室を冷却することが可能となる。また、過度の圧力低
下を防止でき、圧縮機への負荷を軽減できる。【００２９】【００３０】【００３１】また、冷媒を効率よく利用することができ
るので冷媒量を削減でき、可燃性冷媒の漏洩時の危険性
を小さくすることが可能となる。【００３２】【実施例】以下、本発明の実施の形態について図１〜図
１２を用いて説明する。従来例と同一構成についてはそ
の詳細な説明を省略し、同一符号を付す。【００３３】（実施例１）図１は、本発明の実施例１に
おける冷蔵庫の縦断面図、図２は同実施例のタイムチャ
ートである。【００３４】２１は冷蔵庫箱体であり、比較的高温の区
画である冷蔵室４と比較的低温の区画である冷凍室６を
配置してあり、例えばウレタンのような断熱材で周囲と
断熱して構成している。食品等の収納物の出し入れは図
示しない断熱ドアを介して行われる。【００３５】冷蔵室４は冷蔵保存のために通常３〜５℃
で設定されているが、保鮮性向上のため若干低めの温
度、例えば−３〜０℃で設定されることもあり、収納物
によって、使用者が自由に上記のような温度設定を切り
替えることを可能としている場合もある、また、ワイン
や根野菜等の保鮮のために、例えば１０℃前後の若干高
めの温度設定とする場合もある。【００３６】冷凍室６は冷凍保存のために通常−２２〜
−１８℃で設定されているが、保鮮性向上のためより低
温の温度、例えば−３０〜−２５℃で設定されることも
ある。【００３７】冷凍サイクル１２は圧縮機１と凝縮器２と
第一の流路制御手段である第一の電動弁１０と第一のキ
ャピラリ７と第一の蒸発器３と第一のサクションライン
１８を順次接続し、第一の電動弁１０と第一のキャピラ
リ７と第一の蒸発器３と第一のサクションライン１８と
並列になるように第二の流路制御手段である第二の電動
弁１１と第二のキャピラリ８と第二の蒸発器５と第二の
サクションライン１９と第二のサクションライン途中に
逆止弁２０とを接続してある。【００３８】第一、第二の電動弁は例えばパルスモータ
により作動するものであり、開閉の作動中のみ通電され
るものである。【００３９】第一の蒸発器３は冷蔵室４内の、例えば冷
蔵室奥面に配設されており、近傍には冷蔵室４の区画内
空気を第一の蒸発器３に通過させて循環させる第一の電
動ファン１３が設けてある。【００４０】また、第二の蒸発器５は冷凍室６内の、例
えば冷凍室奥面に配設されており、近傍には冷凍室６の
区画内空気を第二の蒸発器５を通過させて循環させる第
二の電動ファン１４が設けてある。【００４１】圧縮機１と凝縮器２と第一の電動弁１０と
第二の電動弁１１と逆止弁２０は可燃性冷媒を使用した
場合に安全性向上の面から冷蔵庫箱体２１内での配管接
続箇所削減のために機械室１５に配設されている。【００４２】各蒸発器から戻ってくる冷媒は圧縮機吸入
管１６を通って、圧縮機１内空間へ放出された後、圧縮
機吐出管１７を通じて吐出される構成である。【００４３】また、圧縮機１は例えば回転数制御で冷媒
循環量を制御し冷凍能力を変化させることができる能力
可変型である。【００４４】また、冷蔵室４と冷凍室６には図示しない
区画内温度を検知する、例えばサーミスタである温度検
知手段を設けてあり、圧縮機１と第一の電動弁１０と第
二の電動弁１１と第一の電動ファン１３と第二の電動フ
ァン１４とを制御する図示しない制御手段とを備えてい
る。【００４５】以上のように構成された冷蔵庫について、
冷蔵室４と冷凍室６の冷却タイミングについて図２のタ
イムチャートを元に説明する。【００４６】圧縮機停止中に、冷蔵室４および冷凍室６
のいずれか一方の温度検知手段が、予め設定された所定
の温度以上を検知すると制御手段はこの信号を受け、例
えば冷凍室６の温度検知手段が予め設定された所定の温
度（ｔ２Ｈ）以上を検知すると圧縮機１と第二の電動フ
ァン１４を作動し、第二の電動弁１１を開放し、第一の
電動弁を閉止する（Ｔ１）。【００４７】圧縮機１の動作により吐出された高温高圧
の冷媒は、凝縮器２にて放熱して凝縮液化し、第二の電
動弁１１を経て第二のキャピラリ８に至る。その後、第
二のキャピラリ８で第二のサクションライン１９と熱交
換しながら減圧されて第二の蒸発器５に至る。第二の電
動ファン１４の作動により冷凍室６内の空気と積極的に
熱交換されて冷媒は第二の蒸発器５内で蒸発気化し熱交
換された空気はより低温の空気となって吐出され冷凍室
６を冷却する。気化した冷媒は、第二のサクションライ
ン１９を経て圧縮機１に吸入される。【００４８】冷凍室６冷却中に冷凍室６の温度検知手段
が予め設定された所定の温度（ｔ２Ｌ）以下を検知する
と、第二の電動弁１１を閉止し、第二の電動ファン１４
を停止して冷凍室６冷却を終了する（Ｔ２）。【００４９】所定時間、第一の電動弁１０と第二の電動
弁１１を閉止し冷媒の流れを遮断した状態で圧縮機を運
転する（Ｔ２〜Ｔ３）。【００５０】所定時間経過後、第一の電動弁１０を開放
し第一の電動ファン１３を作動して冷蔵室４冷却を開始
する（Ｔ３）。【００５１】冷媒は、第一の電動弁１０を経て第一のキ
ャピラリ７に至る。その後、第一のキャピラリ７で第一
のサクションライン１８と熱交換しながら減圧されて第
一の蒸発器３に至る。第一の電動ファン１３の作動によ
り冷蔵室４内の空気と積極的に熱交換されて冷媒は第一
の蒸発器３内で蒸発気化し熱交換された空気は比較的低
温の空気となって吐出され冷蔵室４を冷却する。気化し
た冷媒は、第一のサクションライン１８を経て圧縮機１
に吸入される。【００５２】冷蔵室４冷却中に冷凍室６の温度検知手段
が予め設定された所定の温度（ｔ２Ｈ）以上を検知する
と、第一の電動弁１０を閉止し同時に第一の電動ファン
１３を停止し、同時に第二の電動弁１１を開放し第二の
電動ファン１４を作動し、冷凍室６の冷却を開始する
（Ｔ４）。【００５３】以上の動作を繰り返し、冷媒の流れを切り
替えることにより、冷蔵室４と冷凍室６を交互に冷却
し、冷蔵室４と冷凍室６の温度検知手段が共に予め設定
された所定の温度（ｔ１およびｔ２Ｌ）より低いことを
検知すると、圧縮機１を停止する（Ｔ５）。【００５４】冷凍室冷却終了後、第一の電動弁１０およ
び第二の電動弁１１を所定時間閉止し冷媒の流れを完全
に遮断した状態で圧縮機を運転させることにより圧縮機
内の圧力が通常運転時と比較して低圧となるので、第二
の蒸発器内に滞留していた冷媒を第二の蒸発器から圧縮
機側へ追い出すことが可能となる。その結果、冷蔵室冷
却に切り替わった時に冷蔵室を冷却するのに十分な冷媒
が第一の蒸発器に供給されるので冷媒循環量不足になら
ず、効率よく冷蔵室を冷却することが可能となる。【００５５】また、冷媒を効率よく利用することができ
るので冷媒量を削減でき、可燃性冷媒を用いる場合には
冷媒漏洩時の危険性を小さくすることが可能となる。【００５６】なお、冷蔵室４冷却から冷凍室６冷却に切
り替わる時にも同様に、第一の電動弁１０および第二の
電動弁１１を共に閉止とした状態で所定時間圧縮機１を
運転した後、冷凍室６冷却を開始すると速やかに第一の
蒸発器３内に滞留している冷媒圧縮機１側へ追い出すこ
とができるので効率よく冷凍室冷却を行うことが可能と
なる。【００５７】なお、第一の流路制御手段１０および第二
の流路制御手段１１は各々第一のキャピラリ７および第
二のキャピラリ８の入口側に設置するとしたが出口側に
設置するならば、冷媒減圧後の回路切り替えとなるので
流路制御手段の作動圧力差が小さく、小トルクで良いの
で小型化が可能であり、消費電力の低減にもなる。【００５８】なお、第一の流路制御手段１０および第二
の流路制御手段１１はパルスモーターにより制御される
電動弁としたが電磁弁を用いても同様の効果が得られ
る。【００５９】なお、冷媒の流れを切り替える手段として
第一の流路制御手段１０と第二の流路制御手段１１を用
いた例で説明したが、第一のキャピラリおよび第二のキ
ャピラリへの流路を交互に開閉でき、且つ同様に流路を
閉止できる構造である電動三方弁を用いても同様の効果
が得られ且つ収納性を向上することが可能となる。【００６０】（実施例２）図３は同実施例のタイムチャ
ートである。【００６１】なお、実施例１と同様の制御については説
明を省略する。【００６２】冷凍室６冷却中に冷凍室６の温度検知手段
が予め設定された所定の温度（ｔ２Ｌ）以下を検知する
と、第二の電動弁１１を閉止し、第二の電動ファン１４
を停止して冷凍室６冷却を終了し、圧縮機１の回転数を
上げる（Ｔ６）。【００６３】所定時間、第一の電動弁１０と第二の電動
弁１１を閉止し冷媒の流れを遮断した状態で圧縮機を通
常運転時より高回転で運転する（Ｔ６〜Ｔ７）。【００６４】所定時間経過後、第一の電動弁１０を開放
し第一の電動ファン１３を作動して、圧縮機を通常回転
数に戻し冷蔵室４冷却を開始する（Ｔ７）。【００６５】冷蔵室４冷却中に冷凍室６の温度検知手段
が予め設定された所定の温度（ｔ２Ｈ）以上を検知する
と、第一の電動弁１０を閉止し同時に第一の電動ファン
１３を停止し、同時に第二の電動弁１１を開放し第二の
電動ファン１４を作動し、冷凍室６の冷却を開始する
（Ｔ８）。【００６６】以上の動作を繰り返し、冷媒の流れを切り
替えることにより、冷蔵室４と冷凍室６を交互に冷却
し、冷蔵室４と冷凍室６の温度検知手段が共に予め設定
された所定の温度（ｔ１およびｔ２Ｌ）より低いことを
検知すると、圧縮機１を停止する（Ｔ９）。【００６７】冷凍室６冷却終了後、第一の電動弁１０お
よび第二の電動弁１１を所定時間閉止し冷媒の流れを完
全に遮断した状態で圧縮機１を通常運転時より高回転で
運転させることにより圧縮機１内の圧力が通常運転時と
比較してかなり低圧となり、第二の蒸発器５内に滞留し
ていた冷媒を第二の蒸発器５から圧縮機１側へ速やかに
追い出すことが可能となる。その結果、第一の電動弁１
０および第二の電動弁１１を共に閉止した状態で圧縮機
１を運転する時間を短縮することができ、冷蔵室４庫内
の昇温を低減でき、効率よく冷蔵室４を冷却することが
可能となる。【００６８】なお、第二の蒸発器５の配管温度を検出す
る温度検知手段を設け冷凍室冷却から冷蔵室冷却に切り
替わる時に、温度検知手段が所定温度以下を検出すると
第一の電動弁１０を開放し冷蔵室冷却を開始する制御手
段を備えると過度の圧力低下を防止でき、圧縮機１への
負荷を軽減できる。【００６９】（実施例３）実施例１と同一構成について
はその詳細な説明を省略し、同一符号を付す。【００７０】図４（ａ）は本発明の実施例３における第
二の蒸発器の概略図であり、図４（ｂ）は第二の蒸発器
に用いるフィンの概略図である。【００７１】第二の蒸発器５は平行に並べられ相互間を
気体が流動するフィン２３とフィン２３を貫通し、内部
を冷媒が入口から出口まで重力方向と逆方向に流動する
ことのない構造である伝熱管２２とで構成されている。【００７２】また、２４はフィン内に設けられた伝熱管
２２が貫通する空孔である。【００７３】第二の蒸発器５の伝熱管２２を冷媒が入口
から出口まで重力方向と逆方向に流動することのない構
造にすることにより、第二の蒸発器５内の流路抵抗が小
さくなる。その結果、冷凍室６冷却終了後、第一の電動
弁１０および第二の電動弁１１を所定時間閉止した状態
で圧縮機１を通常運転時より高回転で運転させる際に、
第二の蒸発器５内に滞留していた冷媒を第二の蒸発器５
から圧縮機１側へスムーズに追い出すことができるの
で、第一の電動弁１０および第二の電動弁１１を共に閉
止した状態で圧縮機１を運転する時間をさらに短縮する
ことができ、さらに効率よく冷蔵室４を冷却することが
可能となる。【００７４】また、冷凍室６冷却中、第二の蒸発器５内
の流路抵抗が小さいために圧縮機１へのオイル戻りが良
くなるので、冷媒循環量低下の要因となる第二の蒸発器
５内のオイル溜まりを防止することが可能となる。【００７５】なお、図４に示すように空気側の熱伝達率
を向上するために伝熱管２２を上方から下方にかけて重
力方向に対して交互に下降するような配管構造としてい
るが、重力方向に対して垂直に下降する配管構造であっ
ても良い、なお、本実施例においては図４に示すように
伝熱管２２が水平方向に並ぶことのない配管構造である
ものについて説明したが、図５に示すように伝熱管が水
平方向に並ぶ配管構造であっても冷媒の流れが入口から
出口まで重力方向と逆方向に流動することのない配管構
造であれば同様の効果が得られる。【００７６】なお、図６に示すように第二の蒸発器５の
伝熱管２２を重量方向に傾斜させると、第二の蒸発器５
内の流路抵抗がさらに小さくなり、圧縮機１側へよりス
ムーズに追い出すことができるので、第一の電動弁１０
および第二の電動弁１１を共に閉止した状態で圧縮機１
を運転する時間をさらに短縮することができ、さらに効
率よく冷蔵室４を冷却することが可能となる。【００７７】（実施例４）実施例１と同一構成について
はその詳細な説明を省略し、同一符号を付す。【００７８】図７は本発明の実施例４における冷蔵庫の
縦断面図である。【００７９】２１は冷蔵庫箱体であり、上方部に比較的
高温の区画である冷蔵室４を、下方部に比較的低温部で
ある冷凍室６を配置してあり、冷凍室６と機械室１５の
距離が近い構成となっている。その結果、第二のサクシ
ョンライン１９の配管長が従来に比べて短い構造となっ
ている。【００８０】第二のサクションライン１９の配管長が従
来に比べて短いために、第二のサクションライン１９の
流路抵抗が小さくなる。その結果、冷凍室６冷却終了
後、第一の電動弁１０および第二の電動弁１１を所定時
間閉止した状態で圧縮機１を運転させる際に、第二の蒸
発器５内に滞留していた冷媒を第二の蒸発器５から圧縮
機１側へさらにスムーズに追い出すことができるので、
第一の電動弁１０および第二の電動弁１１を共に閉止し
た状態で圧縮機１を運転する時間をさらに短縮すること
ができ、さらに効率よく冷蔵室４を冷却することが可能
となる。【００８１】（実施例５）実施例１と同一構成について
はその詳細な説明を省略し、同一符号を付す。【００８２】図８は本発明の実施例５における冷蔵庫の
縦断面図である。【００８３】図８において、第二の蒸発器５を出た後、
第二のサクションライン１９を冷蔵庫背面を沿って立ち
上げずに冷蔵庫底面を這わせた後、圧縮機へと繋げる配
管構造となっている。【００８４】また、第二のキャピラリ８と第二のサクシ
ョンライン１９は冷蔵庫底面の断熱材内部において熱交
換している。【００８５】従来、キャピラリと熱交換するために冷蔵
庫背面を立ち上げていたサクションラインを冷蔵庫底面
のスペースを有効利用することにより、第二のサクショ
ンライン１９を冷蔵庫背面を沿って立ち上げない配管構
造とすることが可能となり、第二のサクションライン１
９の流路抵抗が小さくなる。【００８６】その結果、冷凍室６冷却終了後、第一の電
動弁１０および第二の電動弁１１を所定時間閉止した状
態で圧縮機１を運転させる際に、第二の蒸発器５内に滞
留していた冷媒を第二の蒸発器５から圧縮機１側へさら
にスムーズに追い出すことができるので、第一の電動弁
１０および第二の電動弁１１を共に閉止した状態で圧縮
機１を運転する時間をさらに短縮することができ、さら
に効率よく冷蔵室４を冷却することが可能となる。【００８７】（実施例６）実施例１と同一構成について
はその詳細な説明を省略し、同一符号を付す。図９は本
発明の実施例６における冷蔵庫の縦断面であり、図１０
は本発明の実施例６における冷蔵庫の横断面図である。【００８８】図９において、２は冷蔵庫下部に設けられ
た機械室１５内に配設された凝縮器であり、１９は冷蔵
庫背面を沿って立ち上がらずに圧縮機１へと繋がる第二
のサクションラインである。【００８９】また図１０において、凝縮器２と第二のサ
クションライン１９は熱交換している。【００９０】以上の構成により構成された冷蔵庫につい
て、以下冷凍室６冷却時を例としてその動作を説明す
る。【００９１】圧縮機１の動作により吐出された高温高圧
の冷媒は、凝縮器２にて空気および比較的低温である第
二のサクションライン１９との熱交換により放熱して凝
縮液化し、第二の電動弁１１を経て第二のキャピラリ８
に至る。その後、第二のキャピラリ８で減圧されて第二
の蒸発器５に至る、第二の電動ファン１４の作動により
冷凍室６内の空気と積極的に熱交換されて冷媒は第二の
蒸発器５内で蒸発気化し熱交換された空気はより低温の
空気となって吐出され冷凍室６を冷却する。気化した冷
媒は、第二のサクションライン１９に至る。比較的低温
である冷媒は比較的高温である凝縮器２との熱交換によ
り吸熱して圧縮機１に吸入される。【００９２】第二のサクションラインを通る比較的低温
の冷媒により凝縮器を通る比較的高温の冷媒を冷却する
ことができるので、凝縮器２の放熱量が増加し、第二の
キャピラリ入口の過冷却度が大きくなり冷凍能力を向上
することができ、さらに効率よく冷凍室を冷却すること
が可能となる。【００９３】また、第二のサクションライン１９にて比
較的低温である冷媒は、比較的高温である凝縮器２との
熱交換により吸熱し、第二の蒸発器５内で蒸発しきれな
かった冷媒は第二のサクションライン１９内で蒸発する
ので、消費電力の増加および圧縮機１の損傷の原因とな
る液戻りを低減することが可能となる。【００９４】なお、本実施例においては第二のサクショ
ンライン１９を凝縮器２と熱交換させた仕様における冷
凍室冷却の効率向上について説明したが、第一のサクシ
ョンライン１８を凝縮器２と熱交換させた仕様において
も冷蔵室４冷却時に同様の効果が得られる。【００９５】（実施例７）実施例１と同一構成について
はその詳細な説明を省略し、同一符号を付す。【００９６】図１１は本発明の実施例７における冷蔵庫
の縦断面であり、図１２は本発明の実施例７における冷
蔵庫の横断面図である。【００９７】図１１，図１２において２５は機械室１５
内を這う第二のサクションライン下部に設けられた例え
ば樹脂成形された蒸発皿である。【００９８】また、図１１において２６は第二の蒸発器
５の下部に設置された排水口２７を有する例えば樹脂成
形された桶であり、排水口２７は蒸発皿２５に繋がって
いる。【００９９】以上の構成により、第二の蒸発器５に付着
した霜は除霜された後、除霜水となり排水口２７を経て
蒸発皿２５に貯蓄される。【０１００】また、冷凍室冷却時にシステム内の冷媒循
環量が過多になると、第二の蒸発器５内で蒸発しきれな
かった冷媒が圧縮へ戻る液戻りが生じる。液戻りが生じ
ると第二のサクションライン１９の配管温度が低下し、
配管表面に露付きが起こり冷蔵庫設置部に水漏れが生じ
品質問題となるばかりでなく漏電が起こる可能性もあ
り、特に可燃性冷媒を用いる場合には危険である。そこ
で、第二のサクションライン１９下部に蒸発皿を設ける
ことにより液戻り時の露を蒸発皿内に溜めることがで
き、安全性を向上できる。【０１０１】【発明の効果】本発明は、以上説明したような状態で実
施され、以下に記載されるような効果を奏する。【０１０２】可燃性冷媒を用いた冷却システムにおい
て、圧縮機と凝縮器と第一のキャピラリと冷蔵室に備え
た第一の蒸発器とで閉ループを形成するとともに、第一
のキャピラリと第一の蒸発器に並列となるように第二の
キャピラリと冷凍室に備えた第二の蒸発器とを接続し、
流路制御手段により冷媒の流れを切り替えるものであ
り、冷凍室冷却から冷蔵室冷却へ切り替わる時に、所定
時間流路制御手段を閉止した状態で圧縮機を運転した
後、第二の蒸発器の温度検知手段が所定温度以下を検出
すると流路制御手段を第一の蒸発器側に開放して冷蔵室
冷却を開始するものである。【０１０３】この発明によれば、冷凍室冷却終了後、流
路制御手段を所定時間閉止し冷媒の流れを完全に遮断し
た状態で圧縮機を運転させることにより圧縮機内の圧力
が通常運転時と比較して低圧となるので、第二の蒸発器
内に滞留していた冷媒を第二の蒸発器から圧縮機側へ追
い出すことが可能となる。その結果、冷蔵室冷却に切り
替わった時に冷蔵室を冷却するのに十分な冷媒が第一の
蒸発器に供給されるので冷媒循環量不足にならず、効率
よく冷蔵室を冷却することが可能となる。また、過度の
圧力低下を防止でき、圧縮機への負荷を軽減できる。ま
た、冷媒を効率よく利用することができるので冷媒量を
削減でき、可燃性冷媒の漏洩時の危険性を小さくするこ
とが可能となる。【０１０４】【０１０５】また、電動三方弁のように冷媒流路の切り
替えと閉止を単一の流路制御手段で実現すれば、切り替
え時、蒸発器への冷媒循環量不足を解消できるととも
に、流路制御手段の収納性を向上することができる。【０１０６】DETAILED DESCRIPTION OF THE INVENTION [0001] TECHNICAL FIELD The present invention relates to a refrigerator and a refrigerator.
The amount of refrigerant in the cooling system that cools
It relates to high efficiency and safety improvement. [0002] 2. Description of the Related Art FIG. 13 shows a conventional cooling cycle and refrigeration.
Disclosed in Japanese Patent Publication No. 62-22396 as an example of a warehouse
FIG. 1 shows a schematic view of a refrigerator. [0003] 1 is a constant speed compressor, 2 is a condenser, and 3 is a cooler.
The first evaporator is disposed in the storage room 4, and 5 is a freezer.
A second evaporator disposed in the chamber 6; [0004] Reference numeral 7 denotes a first evaporator 3 for cooling the refrigerator compartment.
A first capillary arranged upstream of the refrigerant circuit,
8 is a refrigerant circuit upstream of the second evaporator 5 for cooling the freezer compartment.
Is a second capillary disposed on the side, and 9 is a refrigerator
This is a check valve provided on the downstream side of the second evaporator 5 for rejection. [0005] 10 is located downstream of the first evaporator 3 in the refrigerant circuit.
Reference numeral 11 denotes a first on-off valve provided, and 11 denotes a second capillary valve.
A second on-off valve provided upstream of the refrigerant circuit of
You. In the conventional refrigerator configured as described above,
The operation will be described below. The operation of the refrigeration cycle is performed as follows.
You. First, the refrigerant compressed by the compressor 1 is condensed by the condenser 2.
It is condensed. The condensed refrigerant is also the first capillary 7
Or the pressure is reduced by the second capillary 8,
Into the evaporator 3 and the second evaporator 5 and are vaporized
Thereafter, it is sucked into the compressor 1 again. Relatively low temperature due to evaporation of refrigerant
The first evaporator 3, the second evaporator 5, and the refrigerator compartment 4,
Each room is cooled by the air in the freezing room 6 exchanging heat.
You. The cooling operation of the refrigerator depends on the temperature of each room (not shown).
This is performed as follows by the detection means and the control means. Each temperature detecting means of the refrigerator compartment 4 and the freezer compartment 6 is provided
Compressor 1 starts when a temperature rise above a certain value is detected,
The operation of the freeze cycle is performed. Temperature detection means for refrigerator compartment 4
The first opening / closing valve 10 is opened until the pressure falls below a predetermined value.
Accordingly, the second on-off valve 11 is closed. As a result, the refrigerant flows into the second evaporator 5
It flows only to the first evaporator 3 without performing. At this time
The setting of the evaporation temperature of the refrigeration cycle
The temperature is -5 to 0 ° C with respect to about 5 ° C, and the normal -30
2-2.5 times the coefficient of performance for evaporation temperature of ~ -25 ° C
The operation of the compressor is possible. The refrigerator compartment 4 is cooled and its temperature drops.
When the detection means detects a value equal to or less than a predetermined value, the first on-off valve 10
Is closed, and the second on-off valve 11 is opened. As a result, the refrigerant flows into the second evaporator 5
Then, the freezing room 6 is cooled. The frozen cycle at this time
Temperature of the freezer compartment is about -18 ℃
Cooled at normal evaporation temperature. As described above, the refrigerator compartment 4 and the freezer compartment 6 are evaporated.
Distribute the refrigerant supply time to the cooler
Therefore, when the refrigerator compartment 4 is cooled, the refrigerant is independently supplied to the first evaporator.
High evaporation temperature by eliminating the need for a low-pressure pressure regulating valve
(-5 to 0 ° C), and the compression ratio of the compressor 1 can be reduced.
Driving with a high coefficient of performance to improve efficiency
It is. Further, the check valve 9 is used for evaporating during the cooling of the refrigerator compartment 4.
Since the temperature is high, the refrigerant is prevented from flowing into the second evaporator 5.
It stops. When the freezing room 6 is cooled, a refrigerator room is used.
Normally, the amount of refrigerant is smaller than during cooling of 4.
Becomes excessive in the refrigerant amount. However, the first on-off valve 10
It is provided downstream of the first evaporator 3 and is closed.
Therefore, it is possible to store the refrigerant in the first evaporator 3.
Thus, the amount of refrigerant can be adjusted. [0017] SUMMARY OF THE INVENTION
That is, when the refrigerator compartment 4 and the freezer compartment 6 are connected to the refrigerant supply to the evaporator.
Is distributed and alternately cooled repeatedly, so that the refrigerator compartment 4
Comparison of refrigeration cycle during cooling with good coefficient of performance of compressor 1
Operating at an extremely high evaporation temperature (-5 to 0 ° C)
ing. However, when the refrigerator compartment 4 is cooled, the freezer compartment 6
Temperature is as low as about −18 ° C.
Since the pressure of the second evaporator 5 provided is low,
The refrigerant that has accumulated in the evaporator 5 flows out of the second evaporator 5
Hateful. As a result, sufficient refrigerant is supplied to the first evaporator 3
This will result in insufficient refrigerant circulation and lower efficiency.
You. Due to the above factors, the required amount of refrigerant increases.
However, when using flammable refrigerants, there is
There is a big problem. The present invention solves the above conventional problems.
Refrigeration compartment and freezer compartment
By reducing the amount of refrigerant in the cooling system and improving efficiency.
The aim is to provide refrigerators that are capable of energy
You. [0021] [MEANS FOR SOLVING THE PROBLEMS] To achieve this object
The refrigerator of the present invention comprises a refrigerator and a freezer.
A storage box and a first evaporator in the refrigerator compartment,
A second evaporator, a compressor, a condenser, and a first evaporator.
A capillary, the first evaporator, and a second capillary
And the second evaporator, the first evaporator or the second evaporator.
Alternately open and close the flow path to the two evaporators and open the flow path to both
Closeable flow path control meansAnd the refrigeration cycle consisting of
Combustible natural refrigerant enclosed in the refrigeration cycleWith
The compressor, the condenser, the first capillary and the
Forming a closed loop with the first evaporator,
So as to be in parallel with one capillary and the first evaporator
Connecting the second capillary and the second evaporator,
The refrigerant flow is switched by the flow path control means.
Yes,Temperature detection for detecting the pipe temperature of the second evaporator
Providing means,When switching from freezer compartment cooling to refrigerator compartment cooling
ToWhile the flow path control means is closed for a predetermined time, the pressure
After operating the compressor, the temperature detecting means detects that the temperature is lower than a predetermined temperature.
Upon detection, the flow path control means is opened to the first evaporator side.
Release to start refrigerator coolingIt is characterized by the following. According to the present invention, after the freezer compartment cooling is completed, the flow
The flow control means is closed for a predetermined time to completely shut off the refrigerant flow.
Operating the compressor with the compressor
Is lower than in normal operation, so the second evaporator
Refrigerant staying in the air is transferred from the second evaporator to the compressor side.
It is possible to go out. As a result, when switching to the refrigerator compartment cooling,
Sufficient refrigerant supplied to the first evaporator to cool the refrigerator compartment
The cooling room is not efficiently circulated.
It becomes possible to cool.It also prevents excessive pressure drop.
Can be stopped and the load on the compressor can be reduced. [0024] [0025] [0026] [0027]Also, Refrigerant can be used efficiently
Therefore, the amount of refrigerant can be reduced, and the danger of leakage of flammable refrigerant
Can be reduced. [0028] DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention
Is a refrigerator box composed of a refrigerator compartment and a freezer compartment,
The first evaporator in the refrigerator compartment and the second evaporator in the freezer compartment
Arrange, compressor, condenser, first capillary, front
The first evaporator, the second capillary, and the second evaporator.
Flow to the generator, the first evaporator or the second evaporator
A flow path system that can open and close paths alternately and close the flow path to both sides
MeansAnd a refrigeration cycle consisting of
Enclosed combustible natural refrigerantAnd the compressor and the compressor
A condenser, the first capillary, and the first evaporator.
While forming a closed loop, with the first capillary
The second capillaries are arranged in parallel with the first evaporator.
Connected to the second evaporator and the flow path control means.
The flow of the refrigerant is switched byThe second
A temperature detecting means for detecting a pipe temperature of the evaporator is provided,frozen
When switching from room cooling to refrigerator storage cooling,The predetermined time
The compressor was operated with the flow path control means closed
Later, when the temperature detecting means detects a predetermined temperature or less, the
Open the flow path control means to the first evaporator side to cool the refrigerator
StartAfter cooling the freezer, the flow path is controlled.
The means is closed for a predetermined time and the flow of refrigerant is completely shut off
By operating the compressor at
Since the pressure is lower than during operation, the gas remains in the second evaporator.
Expelled refrigerant from the second evaporator to the compressor
It becomes possible. As a result, it switches to refrigerator compartment cooling.
The first evaporator has enough refrigerant to cool the refrigerator compartment when
To be efficiently cooled
It becomes possible to cool the storage room.Also, excessive pressure low
Lowering can be prevented, and the load on the compressor can be reduced. [0029] [0030] [0031]Also, Refrigerant can be used efficiently
Therefore, the amount of refrigerant can be reduced, and the danger of leakage of flammable refrigerant
Can be reduced. [0032] BRIEF DESCRIPTION OF THE DRAWINGS FIG.
12 will be described. For the same configuration as the conventional example,
Is omitted and the same reference numerals are given. (Embodiment 1) FIG. 1 shows Embodiment 1 of the present invention.
FIG. 2 is a vertical sectional view of the refrigerator in FIG.
It is. Reference numeral 21 denotes a refrigerator box, which is a section having a relatively high temperature.
Refrigerator room 4 which is a picture and freezer room 6 which is a relatively low temperature compartment
It is arranged, for example, with insulation around urethane
Insulated and configured. Figure of putting in and out of things such as food
This is done through an insulated door not shown. The refrigerator compartment 4 is usually at 3 to 5 ° C. for refrigerated storage.
The temperature is set slightly lower to improve freshness.
Degree, for example, it may be set at -3 to 0 ° C.
Allows the user to freely switch the temperature setting as described above.
In some cases, it is possible to change
For freshness of vegetables and root vegetables, for example, slightly higher around 10 ° C
In some cases, a temperature setting may be used. The freezer compartment 6 usually has a temperature range of -22 to refrigerated storage.
Set at -18 ° C, but lower for better freshness
Temperature may be set at a temperature of, for example, -30 to -25 ° C.
is there. The refrigerating cycle 12 includes a compressor 1 and a condenser 2
The first motor-operated valve 10 and the first key
Capillary 7, first evaporator 3, and first suction line
18 are sequentially connected, and the first motor-operated valve 10 and the first capillary are connected.
And the first evaporator 3 and the first suction line 18
The second electric motor which is the second flow path control means so as to be in parallel
The valve 11, the second capillary 8, the second evaporator 5, and the second
In the middle of the suction line 19 and the second suction line
The check valve 20 is connected. The first and second electric valves are, for example, pulse motors.
The power is supplied only during the opening / closing operation.
Things. The first evaporator 3 is, for example, a chiller in the refrigerator compartment 4.
It is located in the back of the storage room, and in the vicinity of the compartment of the refrigerator room 4
A first electrode for circulating air through the first evaporator 3
A moving fan 13 is provided. Further, the second evaporator 5 is provided inside the freezer 6, for example.
For example, it is disposed on the back of the freezer compartment, and near the freezer compartment 6
The second in which the air in the compartment is circulated through the second evaporator 5
Two electric fans 14 are provided. The compressor 1, the condenser 2, the first motor-operated valve 10,
The second electric valve 11 and the check valve 20 use a flammable refrigerant.
Pipe connection in the refrigerator box 21 to improve safety
It is arranged in the machine room 15 to reduce the number of connection points. The refrigerant returning from each evaporator is supplied to the compressor.
After being discharged into the space inside the compressor 1 through the pipe 16,
It is configured to be discharged through the machine discharge pipe 17. The compressor 1 is controlled, for example, by controlling the rotation speed.
Ability to control circulating volume and change refrigeration capacity
It is a variable type. Further, the refrigerator compartment 4 and the freezer compartment 6 are not shown.
Detects the temperature inside the compartment, for example, a temperature sensor such as a thermistor
The compressor 1, the first motor-operated valve 10, and the
The second electric valve 11, the first electric fan 13, and the second electric fan
Control means (not shown) for controlling the
You. Regarding the refrigerator configured as described above,
The timing of cooling the refrigerator compartment 4 and the freezer compartment 6 is shown in FIG.
Explanation will be made based on the im chart. While the compressor is stopped, the refrigerator compartment 4 and the freezer compartment 6
One of the temperature detecting means is set to a predetermined predetermined value.
The control means receives this signal when it detects
For example, if the temperature detecting means of the freezing room 6 is set to a predetermined temperature,
Degree (t2H) or more, the compressor 1 and the second electric fan
Activate the fan 14, open the second motor-operated valve 11, and
The electric valve is closed (T1). High temperature and high pressure discharged by the operation of the compressor 1
Is radiated by the condenser 2 to be condensed and liquefied,
It reaches the second capillary 8 via the valve train 11. Then
Heat exchange with the second suction line 19 in the second capillary 8
Then, the pressure is reduced while reaching the second evaporator 5. Second electricity
By the operation of the moving fan 14, the air in the freezing room 6 is positively
The heat is exchanged, and the refrigerant evaporates and evaporates in the second evaporator 5 and exchanges heat.
The exchanged air is discharged as colder air and
Cool 6 The vaporized refrigerant is supplied to the second suction line.
The refrigerant is sucked into the compressor 1 through the compressor 19. Means for detecting the temperature of the freezing compartment 6 during cooling of the freezing compartment 6
Detects below a predetermined temperature (t2L)
Then, the second electric valve 11 is closed and the second electric fan 14 is closed.
Is stopped and cooling of the freezing compartment 6 is terminated (T2). For a predetermined time, the first motor-operated valve 10 and the second motor-operated valve
Operate the compressor with the valve 11 closed and the refrigerant flow shut off.
(T2 to T3). After a predetermined time has elapsed, the first motor-operated valve 10 is opened.
Activate the first electric fan 13 to start cooling the refrigerator compartment 4
(T3). The refrigerant passes through the first motor-operated valve 10 and enters the first key.
It reaches Capillary 7. After that, the first capillary 7
The pressure is reduced while exchanging heat with the suction line 18
One evaporator 3 is reached. The operation of the first electric fan 13
Heat exchange with the air in the refrigerator compartment 4
The air that has been evaporated and heat exchanged in the evaporator 3 is relatively low
It is discharged as warm air and cools the refrigerator compartment 4. Vaporization
The refrigerant that has passed through the first suction line 18
Inhaled. Temperature detecting means of the freezer compartment 6 during the cooling of the refrigerator compartment 4
Detects a temperature equal to or higher than a predetermined temperature (t2H) set in advance.
And the first electric fan 10 is closed and the first electric fan
13 and at the same time, the second motor-operated valve 11 is opened and the second
Activate the electric fan 14 to start cooling the freezer 6.
(T4). The above operation is repeated to cut off the refrigerant flow.
By alternately cooling the refrigerator compartment 4 and the freezer compartment 6 alternately
And the temperature detecting means of the refrigerator compartment 4 and the freezer compartment 6 are both preset.
That the temperature is lower than the predetermined temperature (t1 and t2L).
Upon detection, the compressor 1 is stopped (T5). After cooling the freezer compartment, the first motor-operated valve 10 and
And the second motor-operated valve 11 is closed for a predetermined time to complete the flow of the refrigerant.
The compressor is operated by shutting off the compressor
The internal pressure is lower than during normal operation.
From the second evaporator
It is possible to drive out to the machine side. As a result, the refrigerator compartment
Sufficient refrigerant to cool the refrigerator compartment when switched to cooling
Is supplied to the first evaporator.
Therefore, it is possible to efficiently cool the refrigerator compartment. Further, the refrigerant can be used efficiently.
Therefore, the amount of refrigerant can be reduced, and when a flammable refrigerant is used,
The danger at the time of refrigerant leakage can be reduced. Incidentally, the cooling from the refrigerator compartment 4 to the freezer compartment 6 is switched.
Similarly, when switching, the first motor-operated valve 10 and the second
The compressor 1 is turned on for a predetermined time while both the motor-operated valves 11 are closed.
After the operation, the cooling of the freezing compartment 6 is started and the first
It is driven out to the refrigerant compressor 1 side which is retained in the evaporator 3.
Can cool the freezer compartment efficiently.
Become. The first flow path control means 10 and the second flow path control means
Of the first capillary 7 and the second
It was set at the entrance side of the second capillary 8 but at the exit side
If installed, the circuit will be switched after the refrigerant is depressurized.
The operating pressure difference of the flow path control means is small and small torque is sufficient.
In addition, the size can be reduced, and the power consumption can be reduced. The first flow path control means 10 and the second flow path control means
Is controlled by a pulse motor.
Although a motor-operated valve was used, a similar effect can be obtained by using a solenoid valve.
You. As means for switching the flow of the refrigerant,
Using the first flow path control means 10 and the second flow path control means 11
As described in the previous example, the first capillary and the second key
The channel to the capillary can be opened and closed alternately, and the channel
The same effect can be obtained by using an electric three-way valve that can be closed.
Can be obtained and the storability can be improved. (Embodiment 2) FIG. 3 shows a time chart of the embodiment.
It is. The control similar to that of the first embodiment will be described.
Description is omitted. Temperature detecting means of the freezing room 6 during freezing of the freezing room 6
Detects below a predetermined temperature (t2L)
Then, the second electric valve 11 is closed and the second electric fan 14 is closed.
To stop the freezing room 6 cooling and reduce the number of revolutions of the compressor 1
Raise (T6). For a predetermined time, the first motor-operated valve 10 and the second motor-operated valve
With the valve 11 closed and the refrigerant flow shut off,
Operate at a higher speed than during normal operation (T6 to T7). After a predetermined time has elapsed, the first motor-operated valve 10 is opened.
Activate the first electric fan 13 to rotate the compressor normally.
Then, the cooling of the refrigerator compartment 4 is started (T7). Means for detecting the temperature of the freezer compartment 6 during the cooling of the refrigerator compartment 4
Detects a temperature equal to or higher than a predetermined temperature (t2H) set in advance.
And the first electric fan 10 is closed and the first electric fan
13 and at the same time, the second motor-operated valve 11 is opened and the second
Activate the electric fan 14 to start cooling the freezer 6.
(T8). The above operation is repeated to cut off the flow of the refrigerant.
By alternately cooling the refrigerator compartment 4 and the freezer compartment 6 alternately
And the temperature detecting means of the refrigerator compartment 4 and the freezer compartment 6 are both preset.
That the temperature is lower than the predetermined temperature (t1 and t2L).
Upon detection, the compressor 1 is stopped (T9). After the freezing compartment 6 has been cooled, the first motor-operated valve 10 and
And the second motor-operated valve 11 is closed for a predetermined time to complete the refrigerant flow.
With the compressor 1 at a higher speed than during normal operation with
By operating the compressor, the pressure in the compressor 1 becomes lower than that during normal operation.
The pressure becomes considerably lower than that of the second evaporator 5,
The refrigerant that has been flowing from the second evaporator 5 to the compressor 1
You can be kicked out. As a result, the first motor-operated valve 1
0 and the second motor-operated valve 11 are both closed.
The operation time of 1 can be reduced, and 4 refrigerator compartments
Temperature can be reduced, and the refrigerator compartment 4 can be efficiently cooled.
It becomes possible. The pipe temperature of the second evaporator 5 is detected.
Temperature detection means to switch from freezer compartment cooling to refrigerator compartment cooling.
When the temperature detection means detects below the predetermined temperature
A controller that opens the first motor-operated valve 10 and starts cooling the refrigerator compartment
By providing a stage, an excessive pressure drop can be prevented, and
The load can be reduced. (Embodiment 3) Regarding the same configuration as Embodiment 1.
Are omitted from detailed description, and are denoted by the same reference numerals. FIG. 4A shows the third embodiment of the present invention.
FIG. 4B is a schematic view of a second evaporator, and FIG.
FIG. The second evaporators 5 are arranged in parallel and
The gas flows through the fins 23 and the fins 23 and
Refrigerant flows from the inlet to the outlet in the direction opposite to the direction of gravity
And a heat transfer tube 22 having no such structure. Reference numeral 24 denotes a heat transfer tube provided in the fin.
22 is a through hole. The refrigerant enters the heat transfer tube 22 of the second evaporator 5.
Structure that does not flow in the direction opposite to the direction of gravity from
The flow path resistance in the second evaporator 5 is reduced.
It will be cheap. As a result, the first electric
The state in which the valve 10 and the second electric valve 11 are closed for a predetermined time
When operating the compressor 1 at a higher speed than during normal operation,
The refrigerant staying in the second evaporator 5 is removed from the second evaporator 5.
From the compressor to the compressor 1 side
Then, the first motor-operated valve 10 and the second motor-operated valve 11 are both closed.
Further shorten the time for operating the compressor 1 in the stopped state
Can cool the refrigerator compartment 4 more efficiently.
It becomes possible. Further, during the cooling of the freezing compartment 6, the inside of the second evaporator 5 is
Oil return to compressor 1 is good due to low flow path resistance
The second evaporator, which causes a decrease in the amount of circulating refrigerant
5 can be prevented from accumulating in the oil. Note that, as shown in FIG.
In order to improve the heat transfer, the heat transfer tube 22
Piping structure that descends alternately in the direction of force
However, the piping structure descends vertically to the direction of gravity.
In this embodiment, as shown in FIG.
It is a piping structure in which the heat transfer tubes 22 are not arranged in a horizontal direction.
The heat transfer tube was made of water as shown in FIG.
Refrigerant flow from inlet
Piping structure that does not flow in the opposite direction of gravity to the outlet
The same effect can be obtained if it is made. As shown in FIG. 6, the second evaporator 5
When the heat transfer tube 22 is inclined in the weight direction, the second evaporator 5
The flow path resistance inside is further reduced, and the
The first motor-operated valve 10
And the second motor-operated valve 11 are closed.
Operation time can be further reduced,
It becomes possible to cool the refrigerator compartment 4 efficiently. (Embodiment 4) Regarding the same configuration as Embodiment 1
Are omitted from detailed description, and are denoted by the same reference numerals. FIG. 7 shows a refrigerator according to the fourth embodiment of the present invention.
It is a longitudinal cross-sectional view. Reference numeral 21 denotes a refrigerator box, which is relatively
The refrigerator compartment 4, which is a high-temperature section, is placed below a relatively low-temperature section.
A certain freezing room 6 is arranged, and the freezing room 6 and the machine room 15
The distance is short. As a result, the second sacrifice
The piping length of the connection line 19 is shorter than before.
ing. When the pipe length of the second suction line 19 is
Because it is shorter than before, the second suction line 19
The flow path resistance is reduced. As a result, the freezing room 6 cooling is completed.
Then, the first motor-operated valve 10 and the second motor-operated valve 11 are
When the compressor 1 is operated in the closed state, the second steam
The refrigerant staying in the generator 5 is compressed from the second evaporator 5
Because you can drive out to the machine 1 side more smoothly,
Close both the first motor-operated valve 10 and the second motor-operated valve 11
To further reduce the time for operating the compressor 1 with the compressor 1
To cool the refrigerator compartment 4 more efficiently
Becomes (Embodiment 5) Regarding the same configuration as in Embodiment 1
Are omitted from detailed description, and are denoted by the same reference numerals. FIG. 8 shows a refrigerator according to the fifth embodiment of the present invention.
It is a longitudinal cross-sectional view. In FIG. 8, after leaving the second evaporator 5,
Stand the second suction line 19 along the back of the refrigerator
After creeping the bottom of the refrigerator without raising it, connect it to the compressor.
It has a tube structure. The second capillary 8 and the second sacrifice
Heating line 19 heat exchanges inside the insulation on the bottom of the refrigerator.
Has been replaced. Conventionally, it is refrigerated to exchange heat with the capillary.
The suction line that started the back of the refrigerator is the bottom of the refrigerator
By effectively utilizing the space of the second
Piping system that does not start line 19 along the back of the refrigerator
And the second suction line 1
9 becomes smaller. As a result, after the freezing compartment 6 has been cooled, the first power
The state in which the valve 10 and the second electric valve 11 are closed for a predetermined time
When the compressor 1 is operated in the state of
The retained refrigerant is discharged from the second evaporator 5 to the compressor 1 side.
First motorized valve because it can be driven out smoothly
Compression with both 10 and second motor-operated valve 11 closed
The time for operating the machine 1 can be further reduced, and
It is possible to efficiently cool the refrigerator compartment 4. (Sixth Embodiment) Regarding the same configuration as the first embodiment
Are omitted from detailed description, and are denoted by the same reference numerals. Figure 9 is a book
FIG. 10 is a vertical cross-sectional view of the refrigerator according to the sixth embodiment of the present invention,
FIG. 13 is a cross-sectional view of a refrigerator according to a sixth embodiment of the present invention. In FIG. 9, 2 is provided at the lower part of the refrigerator.
19 is a condenser provided in the machine room 15 which has been refrigerated.
The second that leads to the compressor 1 without standing along the back of the warehouse
Is the suction line. In FIG. 10, the condenser 2 and the second
The action line 19 exchanges heat. The refrigerator having the above configuration is described.
In the following, the operation will be described with the freezing room 6 being cooled as an example.
You. High temperature and high pressure discharged by the operation of the compressor 1
Refrigerant in the condenser 2 is air and relatively low-temperature refrigerant
The heat is exchanged with the second suction line 19 to release heat and
The second capillary 8 is condensed through the second motor-operated valve 11
Leads to. Thereafter, the pressure is reduced by the second capillary 8 and the second
Operation of the second electric fan 14 which reaches the evaporator 5
The refrigerant is actively exchanged with the air in the freezer 6 and the refrigerant
The air evaporated and heat exchanged in the evaporator 5 has a lower temperature.
It is discharged as air and cools the freezing compartment 6. Vaporized cold
The medium reaches the second suction line 19. Relatively low temperature
Is cooled by heat exchange with the condenser 2, which is relatively hot.
Heat is absorbed by the compressor 1. Relatively low temperature through the second suction line
Cools relatively hot refrigerant passing through the condenser
Therefore, the heat radiation of the condenser 2 is increased,
The degree of subcooling at the capillary inlet increases, improving the refrigeration capacity
Can cool the freezer more efficiently
Becomes possible. Further, the second suction line 19
The relatively low-temperature refrigerant is supplied to the relatively high-temperature condenser 2.
Absorbs heat due to heat exchange and is not completely evaporated in the second evaporator 5
The used refrigerant evaporates in the second suction line 19.
Therefore, power consumption may be increased and the compressor 1 may be damaged.
Liquid return can be reduced. In this embodiment, the second suction
Cooling in the specification in which the heat exchange line 19 is exchanged with the condenser 2.
I explained how to improve the efficiency of freezing chamber cooling.
In the specification in which the heat exchange line 18 exchanges heat with the condenser 2
The same effect can be obtained when the refrigerator compartment 4 is cooled. (Embodiment 7) Regarding the same configuration as in Embodiment 1
Are omitted from detailed description, and are denoted by the same reference numerals. FIG. 11 shows a refrigerator according to the seventh embodiment of the present invention.
FIG. 12 is a cross-sectional view of the cooling device according to the seventh embodiment of the present invention.
It is a cross-sectional view of a storage. In FIGS. 11 and 12, reference numeral 25 denotes a machine room 15.
Illustration provided at the bottom of the second suction line crawling inside
This is an evaporating dish made of resin. In FIG. 11, reference numeral 26 denotes a second evaporator.
5 having a drain port 27 installed at the lower part of
The drain is connected to the evaporating dish 25.
I have. With the above structure, the second evaporator 5 adheres.
After the frost is defrosted, it becomes defrosted water and passes through the drain 27.
It is stored in the evaporating dish 25. Further, the refrigerant circulation in the system during cooling of the freezing room is performed.
If the ring amount becomes excessive, it cannot be completely evaporated in the second evaporator 5.
A liquid return occurs in which the used refrigerant returns to compression. Liquid return occurs
Then, the piping temperature of the second suction line 19 decreases,
Dew condensation on the piping surface causes water leakage at the refrigerator installation part
Not only is it a quality problem, but there is a
This is dangerous especially when a flammable refrigerant is used. There
Then, an evaporating dish is provided below the second suction line 19.
As a result, dew at the time of liquid return can be stored in the evaporating dish.
Safety can be improved. [0101] According to the present invention, the present invention is implemented in the state described above.
And has the following effects. [0102]Cooling system using flammable refrigerant
hand,Prepared for compressor, condenser, first capillary and refrigerator
Form a closed loop with the first evaporator
So that the second capillary is in parallel with the first evaporator
Connect the capillary and the second evaporator provided in the freezer,
The flow of the refrigerant is switched by flow control means.
At the time of switching from freezer compartment cooling to refrigerator compartment cooling.
The compressor was operated with the time flow control means closed
rear,Temperature detection means of the second evaporator detects below a predetermined temperature
Then, the flow path control means is opened to the first evaporator side and the refrigerator compartment is opened.
CoolingTo start. According to the present invention, after cooling the freezing compartment,
The flow control means is closed for a predetermined time to completely shut off the refrigerant flow.
Operating the compressor with the compressor
Is lower than in normal operation, so the second evaporator
Refrigerant staying in the air is transferred from the second evaporator to the compressor side.
It is possible to go out. As a result, we switched to refrigerator compartment cooling.
In the first place, enough refrigerant to cool the refrigerator compartment
Since it is supplied to the evaporator, there is no shortage of refrigerant circulating amount and efficiency
It becomes possible to cool the refrigerator compartment well.Also excessive
Pressure drop can be prevented, and the load on the compressor can be reduced. Ma
Also, since the refrigerant can be used efficiently,
Reduce the risk of flammable refrigerant leakage.
It becomes possible. [0104] In addition, as in the case of an electric three-way valve, the refrigerant flow path is cut off.
If switching and closing are realized by a single channel control means,
The shortage of refrigerant circulation to the evaporator
In addition, the storability of the flow path control means can be improved. [0106]

【図面の簡単な説明】【図１】本発明の請求項１および２の実施例における冷
蔵庫の縦断面図【図２】本発明の請求項１の実施例おける冷蔵庫のタイ
ムチャート【図３】本発明の請求項２の実施例おける冷蔵庫のタイ
ムチャート【図４】（ａ）本発明の請求項３の実施例おける第二の
蒸発器の概略正面図（ｂ）同側面図【図５】同実施例おける第二の蒸発器の概略斜視図【図６】同実施例おける第二の蒸発器の正面図【図７】本発明の請求項４の実施例における冷蔵庫の縦
断面図【図８】本発明の請求項５の実施例における冷蔵庫の縦
断面図【図９】本発明の請求項６の実施例における冷蔵庫の縦
断面図【図１０】本発明の請求項６の実施例における冷蔵庫の
横断面図【図１１】本発明の請求項７の実施例における冷蔵庫の
縦断面図【図１２】本発明の請求項７の実施例における冷蔵庫の
横断面図【図１３】従来の冷蔵庫の概略図【符号の説明】１圧縮機２凝縮器３第一の蒸発器４冷蔵室５第二の蒸発器６冷凍室７第一のキャピラリ８第二のキャピラリ１０第一の流路制御手段１１第二の流路制御手段１２冷凍サイクル１３第一の電動ファン１４第二の電動ファン１５機械室１６圧縮機吸込管１７圧縮機吐出管１８第一のサクションライン１９第二のサクションライン２０逆止弁２１冷蔵庫箱体BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view of a refrigerator in the first and second embodiments of the present invention. FIG. 2 is a time chart of the refrigerator in the first embodiment of the present invention. FIG. 4 is a time chart of a refrigerator according to the second embodiment of the present invention; FIG. 4A is a schematic front view of a second evaporator according to the third embodiment of the present invention; FIG. FIG. 6 is a schematic perspective view of a second evaporator in the embodiment. FIG. 6 is a front view of the second evaporator in the embodiment. FIG. 7 is a longitudinal sectional view of a refrigerator in an embodiment of the present invention. 8 is a longitudinal sectional view of the refrigerator according to the fifth embodiment of the present invention. FIG. 9 is a longitudinal sectional view of the refrigerator according to the sixth embodiment of the present invention. FIG. 10 is a longitudinal sectional view of the refrigerator according to the sixth embodiment of the present invention. FIG. 11 is a longitudinal sectional view of the refrigerator according to the seventh embodiment of the present invention. 13 is a cross-sectional view of a refrigerator according to the seventh embodiment of the present invention. FIG. 13 is a schematic diagram of a conventional refrigerator. [Description of References] 1 Compressor 2 Condenser 3 First evaporator 4 Refrigerator 5 Second Evaporator 6 Freezer 7 First capillary 8 Second capillary 10 First flow path control means 11 Second flow path control means 12 Refrigeration cycle 13 First electric fan 14 Second electric fan 15 Machine room 16 Compressor suction pipe 17 Compressor discharge pipe 18 First suction line 19 Second suction line 20 Check valve 21 Refrigerator box

───────────────────────────────────────────────────── フロントページの続き (56)参考文献特開昭58−219366（ＪＰ，Ａ) 特開平４−43262（ＪＰ，Ａ) 特開平８−170859（ＪＰ，Ａ) 実開昭59−45467（ＪＰ，Ｕ) (58)調査した分野(Int.Cl.⁷，ＤＢ名) F25D 13/00 101 ──────────────────────────────────────────────────続き Continuation of the front page (56) References JP-A-58-219366 (JP, A) JP-A-4-43262 (JP, A) JP-A-8-170859 (JP, A) 45467 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F25D 13/00 101

Claims

(57) [Claims 1] A refrigerator box composed of a refrigerator compartment and a freezer compartment, a first evaporator in the refrigerator compartment, and a second evaporator in the freezer compartment. Disposed, a compressor, a condenser, a first capillary, the first evaporator, a second capillary, and the second evaporator, the first evaporator or the second evaporator. A refrigeration cycle comprising flow control means capable of alternately opening and closing the flow path to the evaporator and closing the flow path to both sides;
A natural refrigerant sealed in a cycle , wherein the compressor, the condenser, the first capillary, and the first evaporator form a closed loop, and the first capillary and the first evaporator. The second capillary and the second evaporator are connected so as to be in parallel with the evaporator, and the flow of the refrigerant is switched by the flow path control means,
Temperature detecting means for detecting a pipe temperature of the second evaporator;
Provided, when switched to the refrigerator compartment cooling from the freezer compartment cooling, place
In a state where the flow path control means is closed for a fixed time, the compressor is operated.
After the operation, the temperature detecting means detects a predetermined temperature or less.
Then, open the flow path control means to the first evaporator side
Refrigerator characterized by starting cooling in a refrigerator.