JP3887587B2

JP3887587B2 - air conditioner

Info

Publication number: JP3887587B2
Application number: JP2002244981A
Authority: JP
Inventors: 郁男水野; 誠三澤; 寛彦延原
Original assignee: Yanmar Co Ltd
Current assignee: Yanmar Co Ltd
Priority date: 2002-08-26
Filing date: 2002-08-26
Publication date: 2007-02-28
Anticipated expiration: 2022-08-26
Also published as: JP2004085036A

Description

【０００１】
【発明の属する技術分野】
本発明は、空調機の施工時において行なわれる既設配管の洗浄能力に特化した空調機の構成と、該空調機による既設配管の洗浄方法に関する。
【０００２】
【従来の技術】
従来の空調機では、ＣＦＣ（クロロフルオロカ−ボン）やＨＣＦＣ（ハイドロクロロフルオロカ−ボン）といった塩素系冷媒（以下、「従来冷媒」とする）が使用されていたが、近年では、分子中に含まれる塩素が成層圏でオゾン層を破壊するため、代替として非塩素系冷媒であるＨＦＣ（ハイドロフルオロカ−ボン）（以下、「新冷媒」とする）が使用されるようなった。この新冷媒への代替に伴い、建物の既設配管を利用したままに、空調機（室外機・室内機）を新設する際には、圧縮機に使用される冷凍機油が異なるため、既設配管内の従来冷媒用の冷凍機油の残留物を除去する洗浄作業が行なわれている。この洗浄作業は、空調機を設置する前段階において、専用の配管洗浄装置を用いて行なわれている。
【０００３】
そして、この洗浄作業における被洗浄物、即ち、従来冷媒用の冷凍機油等の残留物は、新冷媒に対して溶解しないため（図７に示す新冷媒と被洗浄物の非相溶性）、従来は、「冷媒の流れの乱れにより配管壁面に付着した被洗浄物を剥ぎ取る」という理論の元、冷媒を気液二相流で流すことで液単相又はガス単相で流す場合よりも冷媒の流れの乱れを大きくし、既設配管の洗浄を行なっていた。このように、従来は、既設配管を流れる冷媒の状態に着目した洗浄を行なっており、前述の配管洗浄装置では、冷媒を気液二相状態で既設配管内を流すべく、予め冷媒を配管洗浄装置内で気液二相状態とするための冷媒回路設計としていた。
【０００４】
【発明が解決しようとする課題】
ところが、上述の既設配管は、建物内外に複雑に張り巡らされており、また、分岐点や角部も多く、冷媒の圧力変動が生じ易いものである。このように、洗浄装置内で気液二相状態とされた冷媒を、その気液二相状態を維持したままに既設配管の全区間を流すことは実際上極めて困難であるといえるとともに、既設配管内を流れる冷媒の状態を厳密に把握することも実際上極めて困難である。このようなことから、完全な気液二相状態で洗浄が行なわれる情況を作るのは困難であるといえる。
【０００５】
そこで、既設配管内を流れる冷媒の液体・気体といった相の状態に依存することなく、上記被洗浄物を確実に剥ぎ取ることで、既設配管内を効果的に洗浄を行なう手段の検討を行い、発明者らは、新冷媒を使用する冷媒回路にて使用されＰＶＥ（ポリビニールエーテル）などの合成油からなる圧縮機用の冷凍機油と、上述の被洗浄物である従来冷媒用の冷凍機油の相溶性に着目した（図７に示す冷凍機油（合成油）と被洗浄物の相溶性）。図８に示すグラフは、新冷媒（ＨＦＣ系冷媒）の冷媒回路の圧縮機に用いられる合成油からなる冷凍機油と、従来冷媒（ＣＦＣ系冷媒）の冷媒回路の圧縮機に用いられる鉱油からなる冷凍機油の相溶性の大小と、合成油からなる冷凍機油の温度の関係を示したグラフである。このグラフから、合成油からなる冷凍機油の温度が高くなるほど、両者の相溶性は大きくなることが解り、この合成油からなる冷凍機油の温度を高めた状態で既設配管に流すことができれば、被洗浄物（鉱油）を確実に溶かした上での洗浄を行なうことが可能となる。
【０００６】
ここで、従来の一般的な空調機の冷媒回路においては、新冷媒用の冷凍機油（合成油）をオイルセパレータにより分離し、再び圧縮機へ還流させる構成としているが、このオイルセパレータにおいては、冷凍機油を完全に分離することができないといった問題から、室外機配管を循環してアキュムレータに流れ込んだ冷凍機油を、Ｕ字管に備える油吸入孔より取り込んで、再び圧縮機に吸入させるようにしている。このように、オイルセパレータを通過後の冷媒中には微量の冷凍機油（合成油）が含有される点に着目し、この微量の冷凍機油（合成油）を既設配管の洗浄に有効に作用させる手段を検討した。
【０００７】
本発明は、以上に述べた両冷凍機油の温度と相溶性との関係に着目しつつ検討を行なうことで完成されたものであり、冷媒中に含まれる微量の冷凍機油（合成油）を、高温状態として既設配管内を通過させることで、鉱油からなる冷凍機油（被洗浄物）を冷凍機油（合成油）に溶解させ、被洗浄物の管壁からの剥離性の向上、即ち、既設配管の洗浄性の向上を図るとともに、この既設配管の洗浄を専用の洗浄装置によらずに新設の空調機自体で行なおうとするものである。
【０００８】
【課題を解決するための手段】
本発明の解決しようとする課題は以上のごとくであり、次に該課題を解決する為の手段を説明する。
空調機の施工時において、既設配管の洗浄を可能とする空調機であって、圧縮機（２）の吐出側に配置されるオイルセパレータ（１０）の出口側と、圧縮機（２）の吸入側を結ぶ第一冷媒バイパス管（７１）を設け、該第一冷媒バイパス管（７１）に第一冷媒バイパス弁（６１）を設け、冷媒回路にて新冷媒として使用される圧縮機用の冷凍機油を、被洗浄物である従来冷媒（ＣＦＣ系冷媒）の冷媒回路の圧縮機に用いられる鉱油からなる冷凍機油に対して相溶性を具備するＰＶＥ（ポリビニールエーテル）などの合成油を使用し、空調機の施工時の所定時間、前記第一冷媒バイパス弁（６１）を開いて、第一冷媒バイパス管（７１）より吐出冷媒を圧縮機（２）の吸入側にバイパスし、圧縮機（２）を吐出した後の冷媒の一部を再圧縮させ、吐出圧力を所定値よりも大とすることで、新冷媒中に含まれる合成油よりなる冷凍機油の温度上昇を図り、被洗浄物に対する冷凍機油の洗浄性の向上を図るものである。
【０００９】
【発明の実施の形態】
次に、本発明の実施の形態を、図面に基づいて説明する。
図１は本発明を適用したエンジンヒートポンプの冷媒回路図、図２は制御装置及び作動装置類の構成を示すブロック図、図３は既設配管の洗浄を行う第二の実施形態の構成を示す図、図４は同じく第三の実施形態の構成を示す図、図５は同じく第五の実施形態の構成を示す図、図６は同じく第六の実施形態の構成を示す図、図７は冷凍機油（合成油）と被洗浄物の相溶性を示す図、図８は冷凍機油の相溶性の大小と温度の関係を示したグラフである。
【００１０】
図１に示す冷媒回路図は、エンジン３で圧縮機２を駆動するエンジンヒートポンプの室外機１に備えた構成の実施例を示すものである。尚、以下の説明では、エンジンヒートポンプの室外機１の実施例とするが、本発明は、「エンジンヒートポンプ」に限らず、「電気エアコン」等、空調機全般に適用可能である。
【００１１】
図１において、空調機の室外機１は、空調を必要とする建物等の外に設置されるものであり、圧縮機２、冷媒蒸発熱供給器としてのエンジン廃熱回収器４、室外熱交換器５、アキュムレータ６、リキッドレシーバ７等の装置と、四方弁８、室外機配管８１・８２、オイルセパレータ１０等の弁・配管・フィルタ類より冷媒回路を形成している。
【００１２】
ここで、オイルセパレータ１０は、新冷媒用の冷凍機油（合成油）を分離して、再び圧縮機２へ還流させるものであるが、このオイルセパレータ１０では、冷凍機油（合成油）を完全に分離することができないことから、該オイルセパレータ１０を通過後の冷媒中には微量の冷凍機油（合成油）が含有されるものである。
【００１３】
また、前記圧縮機２は、クラッチ３３によるエンジン３の駆動の断接により内部の回転体を駆動する構成としており、このクラッチ３３は電磁クラッチより構成され、その断接は、室外機１を運転制御するコントローラ２５により制御されるようにしている。また、前記エンジン廃熱回収器４は、圧縮機２の吸入側、即ち、圧縮機２に吸入される冷媒の流れにおいて、圧縮機２の上流側に設けられている。尚、このエンジン廃熱回収器４は、エンジンヒートポンプにて本発明を実施する場合において冷媒蒸発熱供給器として適用されるものであり、電気エアコンにおいて実施する際は、電熱ヒータ等によりエンジン廃熱回収器４と同等の機能を代替させる構成とするものである。
【００１４】
また、室外機１には、ラジエータ１１と、冷却水三方弁１２、サーモスタット１３、冷却水ポンプ１４、排ガス熱交換器１５、冷却水管１６が備えられ、前記エンジン３とともに、エンジン冷却水回路を構成している。
【００１５】
また、図１に示すごとく、前記アキュムレータ６の底部には、回収弁２８を設けた排出管１９が接続され、該排出管１９の排出口側には、回収器２７が設けられている。また、アキュムレータ６内にはＵ字管８３を設け、該Ｕ字管８３の下部壁面には、上述したように、オイルセパレータ１０では分離されなかった圧縮機２の冷凍機油を、圧縮機２へ吸入させるための油吸入孔２４が設けられている。
【００１６】
また、前記室外熱交換器５とリキッドレシーバ７を接続する室外機配管８１には、暖房用膨張弁２１が設けられ、暖房時において室外熱交換器５に流入する直前にて冷媒の圧力制御を行なうようにしている。
【００１７】
また、アキュムレータ６のＵ字管８３の一端は上方を開口してアキュムレータ６の容器４０内の上部空間内に開放し、Ｕ字管８３の他端は圧縮機２の吸入側に主吐出管８４を介して通じており、該主吐出管８４には吐出管電磁開閉弁２９が設けられている。また、前記主吐出管８４おいて、吐出管電磁開閉弁２９の設置箇所よりも圧縮機２側（下流側）には、副吐出管８５の一端が接続されており、該副吐出管８５の他端はアキュムレータ６の容器４０内に挿入されて、該容器４０の上部内空間に通じている。また、これら主吐出管８４と、副吐出管８５には、それぞれ、オイルセパレータ１０の底部と連通する配管１０ａ・１０ｂが接続されており、オイルセパレータ１０にて分離された冷凍機油は、主吐出管８４・副吐出管８５に流れ、再び圧縮機２へと供給されるようになっている。また、副吐出管８５には、前記回収器２７の上部内空間に通じるガス冷媒戻り管８６が接続され、該ガス戻り管８６には、戻り管電磁開閉弁９４が設けられている。
【００１８】
また、前記オイルセパレータ１０と四方弁８とを結ぶ室外機配管７７には、第一冷媒バイパス弁６１を設けた第一冷媒バイパス管７１が接続され、圧縮機２から吐出してオイルセパレータ１０を通過した高温高圧ガス冷媒の一部を圧縮機２の吸入側の配管となる主吐出管８４に導くようにしている。
【００１９】
以上の室外機１の構成に対し、室内機３０は、空調を必要とする建物内等に設置されるものであり、室内熱交換器３１、室内機ファン３０ｆ、室内熱交換器用膨張弁３２等を備え、既設配管２０に接続される。尚、図においては、一機の室内機３０を設置した構成としているが、台数については、特に限定されるものではなく、二以上の室内機を配設する構成であってもよい。
【００２０】
図２は、エンジンヒートポンプの運転を制御する制御装置と、作動装置類の構成を示すものであり、制御装置であるコントローラ２５は、電磁弁からなる暖房用膨張弁２１、回収弁２８、吐出管電磁開閉弁２９、戻り管電磁開閉弁９４、室内熱交換器用膨張弁３２、冷却水三方弁１２と接続され、これらの弁の開閉制御を行い、更には、冷却水ポンプ１４のＯＮ・ＯＦＦ、エンジン３の回転数の制御、前記四方弁８の流路切換や、前記クラッチ３３の断接の制御を行なう構成としている。また、これらに加え、後述する冷媒回路の実施形態に応じ、図２に示すごとく、コントローラ２５は、電磁弁からなる第一〜第五冷媒バイパス弁（６１〜６５）や、洗浄用膨張弁２２、暖機用膨張弁２３、オイルセパレータバイパス三方弁５０の開度調整を行なうとともに、圧縮機２吐出後の冷媒圧力を検出する高圧圧力センサ６６の検出値が入力されるようになっている。
【００２１】
そして、図１に示すごとく、以上の室外機１と室内機３０とを、第一開閉弁１７・第二開閉弁１８にて既設配管２０を介して連通し、該既設配管２０に新冷媒を循環させるとともに、コントローラ２５による四方弁８の制御により、循環冷媒の流路を変更することで、暖房運転及び冷房運転を行なう構成としている。
【００２２】
以上のように構成したエンジンヒートポンプにおいて行なう暖房運転について説明すると、図１に示すごとく、圧縮機２により圧縮された冷媒は、高温高圧過熱蒸気の状態として、暖房方向に切換えられた四方弁８を経由して、室外機配管８２を通り、第一開閉弁１７から既設配管２０内を通って室内熱交換器３１へ送出される。室内熱交換器３１においては、高温高圧過熱蒸気状態の冷媒から室内空気に熱が放出されて、冷媒は高圧液体状態となる。この熱放出により室内の暖房が行われる。
【００２３】
高圧液体状態の冷媒は、第二開閉弁１８を通過して室外機配管８１へ戻り、リキッドレシーバ７、室外機配管７２’・７９を経由した後に、暖房用膨張弁２１にて急激に膨張して、低温低圧蒸気状態の冷媒となり、室外熱交換器５を通過する間に、外気より熱を得て加熱状態の蒸気となる。そして、加熱状態の蒸気は、四方弁８を経由し、エンジン廃熱回収器４にて蒸発してガス冷媒となってアキュムレータ６に流入し、圧縮機２に吸入され、上述の運転を繰り返す。
【００２４】
次に、冷房運転について説明すると、図１に示すごとく、圧縮機２により圧縮された冷媒は、高温高圧過飽和蒸気の冷媒（高温高圧ガス冷媒）となり、オイルセパレータ１０、四方弁８を経由して室外熱交換器５に圧送される。冷媒は、室外熱交換器５の冷却フィンを通過する間に室外ファン５ｆにより冷却されて、高温高圧過熱状態から高圧液相状態に液化する。
【００２５】
室外熱交換器５にて高圧液相状態になった冷媒は、リキッドレシーバ７にて気液分離され、室外機配管８１を通り、第二開閉弁１８に接続された既設配管２０内を通って、室内機３０へ送られる。この室内機３０においては、室内熱交換器用膨張弁３２にて減圧された後、室内熱交換器３１にて室内空気から熱を吸収して蒸発することにより室内空気を冷却し、室内機ファン３０ｆにより室内に送風して冷房効果をもたらすようにしている。その後、室内熱交換器３１にて蒸発した冷媒が、既設配管２０内を通って、第一開閉弁１７を通過し、四方弁８を経由して、アキュムレータ６に戻り、ガス冷媒となって圧縮機２に吸入され、上述の運転を繰り返す。
【００２６】
そして、上記構成とすることにより、エンジンヒートポンプ自体で既設配管２０の洗浄を行なえる構成となっているものであり、具体的には、エンジンヒートポンプの施工の際において、冷房運転又は暖房運転を行い、既設配管２０内に冷媒を通過させ、冷媒及び冷媒中に含有する冷凍機油（合成油）にて既設配管２０に付着した被洗浄物を剥ぎ取り、剥ぎ取られた被洗浄物を冷媒とともにエンジン廃熱回収器４へ流し、該エンジン廃熱回収器４にて冷媒を蒸発させてガス冷媒とする一方、被洗浄物を液体又は固体（不溶解物）のままにしてアキュムレータ６へ流入させ、アキュムレータ６へ流入した被洗浄物を、排出管１９より回収器２７へ排出するものである。以上のように、アキュムレータ６にて被洗浄物を分離し、該被洗浄物を回収器２７にて回収する構成として、専用の配管洗浄装置によらず、エンジンヒートポンプ自体にて既設配管２０の洗浄を行なう構成としている。
【００２７】
以上が本発明を適用する空調機（エンジンヒートポンプ）の構成と、該空調機自体による配管洗浄の概要であって、以下では、空調機の構成の詳細と、それに基づく効果について説明する。
【００２８】
本発明では、上述のごとく、専用の配管洗浄装置を用いることなく空調機（エンジンヒートポンプ）自体で配管洗浄を行なうものである。そして、この配管洗浄をより確実に行なうべく、既設配管２０を流れる冷媒の圧力をより高圧にする、換言すれば、圧縮機２の冷媒吐出圧力を所定値よりも大に維持することにより、冷媒の温度を上昇させ、この冷媒温度の上昇に伴わせて冷凍機油（合成油）の温度をより高くすることで、冷凍機油（合成油）と被洗浄物（鉱油）との相溶性を向上し、被洗浄物を管壁から剥離しやすいようにする、つまりは、冷凍機油（合成油）を含む循環冷媒による洗浄力を高めて洗浄を行なえる構成としている。以下、既設配管２０内に流す冷媒の圧力をより高圧とするための実施形態について説明する。
【００２９】
（１）第一の実施形態
本実施形態は、図１に示す冷媒回路構成により行われるものある。
即ち、室外熱交換器５と、圧縮機２と、該圧縮機２を吐出した冷媒中の冷凍機油を分離するオイルセパレータ１０と、冷房時と暖房時の冷媒流路を切替える四方弁８と、リキッドレシーバ７と、冷媒蒸発熱供給器（本明細書中ではエンジン廃熱回収器４）と、アキュムレータ６と、暖房用膨張弁２１と、これらを連通する冷媒配管を備える空調機（本明細書中ではエンジンヒートポンプ）において、前記オイルセパレータ１０と四方弁８とを結ぶ室外機配管７７と、圧縮機２の吸入側の主吐出管８４（又は副吐出管８５）とを結ぶ第一冷媒バイパス管７１を設けるとともに、前記第一冷媒バイパス管７１に、第一冷媒バイパス弁６１を設けた構成とするものである。本実施形態の目的とするところは、圧縮機２を吐出してオイルセパレータ１０を通過後の高温高圧ガス冷媒を、第一冷媒バイパス管７１を通して圧縮機２の吸入側の冷媒配管、即ち、主吐出管８４にバイパスさせることにより、圧縮機２に吸入される冷媒圧力を高めて圧縮機２から吐出される冷媒圧力をより高くするとともに、このように高圧となった冷媒を既設配管２０に通過させ、冷媒中に含まれる高温の冷凍機油（合成油）とともに既設配管２０内の洗浄を行うことである。つまりは、圧縮機２から、より高圧のガス冷媒を吐出させ、冷媒の高圧化に伴う冷媒の高温化をもとに、該冷媒中に含まれる冷凍機油（合成油）の温度上昇を図り、被洗浄物に対する冷凍機油（合成油）の洗浄性の向上を図るものである。
【００３０】
本構成において、圧縮機２より吐出した冷媒は、オイルセパレータ１０を通過後、一部は直接四方弁８へ送られる一方、残りは上記第一冷媒バイパス弁６１の開度に応じ、第一冷媒バイパス管７１を通じて圧縮機２の吸入側の主吐出管８４へ送られ再び圧縮機２へ吸入され、再圧縮されたのち、より高圧状態で圧縮機２より吐出する。つまりは、一度圧縮機２を吐出した後の冷媒の一部を再圧縮させることにより、より高圧の冷媒を圧縮機２より吐出させるのである。ここで、前記第一冷媒バイパス弁６１の開度は、圧縮機２吐出後の高圧圧力センサ６６による冷媒吐出圧力の検出値が所定値よりも大に維持されるようコントローラ２５で制御されるものである。尚、ここでいう冷媒吐出圧力の所定値は、試験により決定し、予めコントローラ２５に記憶されるものである。そして、圧縮機２より吐出した冷媒は、四方弁８より室外熱交換器５を介して室内機３０（冷房時冷媒流路設定の場合）へ流れる、又は四方弁８より直接室内機３０へ流れる（暖房時冷媒流路設定の場合）際に、既設配管２０を通過して管内壁を洗浄し、また、室内機３０から室外機１へ戻る際にも、既設配管２０を通過して管内壁を洗浄する。ここで、この既設配管２０を通過する冷媒は、上述した圧縮機２による再圧縮がされないものと比較して、より高圧高温の状態で既設配管２０を通過することになり、この冷媒中に含まれる冷凍機油（合成油）を温度が高い状態、即ち、高い洗浄性を持った状態で流すことができ、既設配管２０の管内壁に付着した被洗浄物（鉱油）を確実に剥離させた上で洗浄することができるとともに、その高い洗浄性から短時間での洗浄の完了を実現させるものである。
【００３１】
（２）第二の実施形態
本実施形態は、図３に示す冷媒回路構成により行われるものある。即ち、前記空調機の室外機１の冷媒配管において、四方弁８から室内機３０へ向かう冷媒の流れる冷媒配管に、冷媒の圧力を制御する洗浄用膨張弁２２・２２’を設けた構成とするものである。本実施形態の目的とするところは、第一の実施形態の構成に基づいた上で、圧縮機２から吐出される高圧の冷媒の圧力を、既設配管２０へ流入する直前において洗浄用膨張弁２２・２２’により制御することで、圧力制御された冷媒を既設配管２０へ流入させ、既設配管２０の管内径や長さに応じた配管洗浄を可能とするとともに、上記再圧縮により圧力が過剰となった際においても、既設配管２０へ流入する直前において減圧させることにより既設配管２０の損傷を防ぐ、換言すれば、冷媒圧力を洗浄にとって好適な値（許容最大圧力）に制御することを目的とするものである。尚、図３に示す構成において、圧縮機２より吐出して四方弁８、室外熱交換器５を経由させた冷媒を既設配管２０へ流す室外機配管８１に設けた洗浄用膨張弁２２は、該洗浄用膨張弁２２にて既設配管２０へ流入しようとする冷媒の圧力を制御するものであり、四方弁８を冷房時冷媒流路設定として洗浄運転を行う場合に機能させるものである。一方、四方弁８を暖房時冷媒流路設定として洗浄運転を行う場合では、圧縮機２より吐出して四方弁８を経由した冷媒を直接既設配管２０へ流す室外機配管８２に設けた洗浄用膨張弁２２’を機能させるものである。
【００３２】
本実施形態において、四方弁８を冷房時冷媒流路設定として洗浄運転を行う場合について説明すると、冷房時に圧縮機２より吐出される高温高圧ガス冷媒は、四方弁８を通過後、室外熱交換器５にて放熱して高温高圧液冷媒となった後、室外機配管８１から既設配管２０へ流入する直前において洗浄用膨張弁２２により圧力制御を行い、既設配管２０内で冷媒を矢印Ａ方向に流すことで洗浄するものである。尚、洗浄用膨張弁２２を通過する際に減圧されるが、該洗浄用膨張弁２２を通過するまでは高温高圧液冷媒であることから、該冷媒に含まれる冷凍機油（合成油）は高温状態であり、高い洗浄性を持った状態で既設配管２０へ流入し、既設配管２０を確実に洗浄することができる。
【００３３】
また、本実施形態において、四方弁８を暖房時冷媒流路設定として洗浄運転を行う場合について説明すると、冷房時圧縮機２より吐出される高温高圧ガス冷媒は、四方弁８を通過後、室外機配管８２から既設配管２０へ流入する直前において洗浄用膨張弁２２’により圧力制御を行い、既設配管２０内で冷媒を矢印Ｂ方向に流すことで洗浄するものである。この設定による洗浄運転では、圧縮機２吐出後の冷媒は、室外熱交換器５を通過させることなく既設配管２０に流入するので、上記冷房時冷媒流量設定とする場合に比して、冷媒を、より高温の状態で既設配管２０を循環させることができるといった点で有効である。
【００３４】
また、四方弁８の切換えにより、既設配管２０内で冷媒を矢印Ａと矢印Ｂの双方向に流すことにより、第一開閉弁１７と室内機３０とを結ぶ経路と、第二開閉弁１８と室内機３０とを結ぶ経路の両経路を均一に洗浄することもできる。
【００３５】
（３）第三の実施形態
本実施形態は、図４に示す冷媒回路構成により行われるものである。即ち、前記四方弁８から冷媒蒸発熱供給器（本明細書中ではエンジン廃熱回収器４）へ冷媒を流す室外機配管４７と、前記リキッドレシーバ７を結ぶ第二冷媒バイパス管７２を設けるとともに、該第二冷媒バイパス管７２に第二冷媒バイパス弁６２を設け、前記四方弁８が暖房時冷媒流路設定での冷媒流れにおける、四方弁８の下流側の室外機１の室外機配管８２と、前記室外熱交換器５と暖房用膨張弁２１との間の室外機配管８１ａとを結ぶ第三冷媒バイパス管７３を設けるとともに、該第三冷媒バイパス管７３に第三冷媒バイパス弁６３を設けた構成としている。本実施形態の目的とするところは、洗浄用膨張弁２２・２２’を備えた構成とする上記第二の実施形態において、四方弁８を冷房時冷媒流路設定として洗浄運転を行う際に、既設配管２０に流していた冷媒を逆向きに流すことを可能として、既設配管２０内を均一に洗浄すること、つまりは、既設配管２０内を流す冷媒の流れの向きを切り替えることで、既設配管２０内を流れる過程での冷媒及び冷凍機油（合成油）の温度低下による洗浄性の低下を防止し、より確実に既設配管２０内を洗浄することを目的とするものである。本実施形態においては、第一開閉弁１７・第二開閉弁１８を開いた状態において、まずは第三冷媒バイパス弁６３を閉じるとともに、暖房用膨張弁２１を開くことにより、室外機配管８１側に冷媒を流す設定とし、洗浄用膨張弁２２にて圧力制御を行いつつ、第二開閉弁１８より既設配管２０内へ冷媒を流入させて、既設配管２０内で、図において矢印Ａの向きに冷媒を流して所定時間の洗浄を行う。そののちに、洗浄用膨張弁２２’を閉じるとともに、暖房用膨張弁２１を閉じる一方、第三冷媒バイパス弁６３にて圧力制御をしつつ第三冷媒バイパス管７３へ冷媒を流し、第一開閉弁１７より既設配管２０内へ冷媒を流入させて、既設配管２０内で、図において矢印Ｂの向きに冷媒を流して所定時間の洗浄を行うものである。以上のように、既設配管２０内で冷媒を双方向に流すことにより、第一開閉弁１７と室内機３０とを結ぶ経路と、第二開閉弁１８と室内機３０とを結ぶ経路の両経路を限りなく同一条件に近い状態で洗浄することが可能となり、既設配管２０を均一に洗浄することができる。
【００３６】
さらに、本実施形態では、四方弁８を冷房時流路設定としつつ、第三冷媒バイパス管７３内に冷媒を通過させることで、既設配管２０内を矢印Ｂの向きに冷媒を流すとともに、室内機３０側より第二開閉弁１８を通って室外機１へ戻った冷媒を、一時リキッドレシーバ７に貯溜した後（暖房用膨張弁２１は閉じている）、リキッドレシーバ７より第二冷媒バイパス管７２’・７２を通過させたうえで、エンジン廃熱回収器４を通過させる回路を構成しており、該エンジン廃熱回収器４にて冷媒を蒸発させるとともに、冷媒にて洗浄された被洗浄物を、液体又は固体（不溶解物）のままアキュムレータ６へ流し、該アキュムレータ６にて分離できるようになっている。このように、第三冷媒バイパス管７３を通過させて既設配管２０の洗浄を行なう場合においては、第二冷媒バイパス管７２を通過させることで、室外熱交換器５内への冷媒の流れをバイパスさせることを可能としており、被洗浄物の室外熱交換器５の配管内への付着を防止できるようになっている。
【００３７】
（４）第四の実施形態
本実施形態は、図３又は図４に示す冷媒回路構成により行われるものである。即ち、前記四方弁８から冷媒蒸発熱供給器（本明細書中ではエンジン廃熱回収器４）へ冷媒を流す室外機配管４７と、前記リキッドレシーバ７を結ぶ第二冷媒バイパス管７２を設けるとともに、該第二冷媒バイパス管７２に第二冷媒バイパス弁６２を設けた構成としている。本実施形態の目的とするところは、第一又は第二の実施形態において、四方弁８を暖房時冷媒流路設定として、高温高圧ガス冷媒を室外機配管８２を通して第一開閉弁１７より既設配管２０へ流入させることで、該高温高圧ガス冷媒に含まれる冷凍機油を冷媒とともに洗浄性の高い高温状態で既設配管２０を洗浄することにより、より確実に洗浄を行なおうとするものである。本実施形態においては、前記四方弁８を暖房時流路設定としつつ、暖房用膨張弁２１を全閉とした状態で、圧縮機２吐出後の高温高圧ガス冷媒を室外機配管８２に流し、第一開閉弁１７を通過して既設配管２０へ流入させる。既設配管２０内では、被洗浄物が、高温の冷凍機油（合成油）により溶かされて管内壁より剥離し、高温高圧ガス冷媒とともに第二開閉弁１８を通過して室外機配管８１へ流入し、一時リキッドレシーバ７に貯溜させる。そして、被洗浄物を冷媒とともに第二冷媒バイパス管７２’・７２を通して、エンジン廃熱回収器４へ導くことで、アキュムレータ６にて被洗浄物と冷媒とを気液分離させるものである。以上のように、既設配管２０を高温高圧ガス冷媒に含有される洗浄性の高い状態の冷凍機油（合成油）により洗浄することで、既設配管２０の管内壁を確実に洗浄することができる。尚、上記第三の実施態様の後段と同様、被洗浄物を含んだ冷媒は、室外熱交換器５をバイパスしてアキュムレータ６へ導かれるため、被洗浄物の室外熱交換器５の配管内への付着を防止することができる。
【００３８】
（５）第五の実施形態
本実施形態は、図５に示す冷媒回路構成により行われるものである。即ち、リキッドレシーバ７に、該リキッドレシーバ７内の液体を攪拌する攪拌手段を設けるものであって、該攪拌手段は、圧縮機２から室外熱交換器５へ冷媒を流す室外機配管７７と、前記リキッドレシーバ７とを連通する第四冷媒バイパス管７４を設けるとともに、該第四冷媒バイパス管７４に第四冷媒バイパス弁６４を設けた構成とするものである。また、前記第四冷媒バイパス管７４の端部開口を、リキッドレシーバ７の底部近傍に配する構成とするものである。本実施形態の目的とするところは、第三及び第四の実施形態にて、洗浄後の冷媒等を一時リキッドレシーバ７に貯溜する場合において、第四冷媒バイパス弁６４を通じてリキッドレシーバ７の底部に圧入する高温高圧ガス冷媒により、冷媒等を攪拌することで、冷媒に冷凍機油と被洗浄物を混合させ、冷媒とともに、冷凍機油と被洗浄物を第二冷媒バイパス管７２を通じて流すことにより、リキッドレシーバ７内に冷凍機油や被洗浄物を残留させないことである。本実施形態では、第三及び第四の実施形態において、既設配管２０内に冷媒を矢印Ｂの方向へ流して洗浄を行なう際に、前記第四冷媒バイパス弁６４を開くことにより、リキッドレシーバ７内へ高温高圧ガス冷媒を圧入して、リキッドレシーバ７内の冷媒、冷凍機油、被洗浄物を攪拌し、冷媒の上面に浮遊する冷凍機油と被洗浄物を冷媒中に混合させるものである。また、上記第四冷媒バイパス弁６４の開閉については、連続的に開く制御、又は間欠的に開く制御のいずれの制御であってもよい。以上のようにして、リキッドレシーバ７内を攪拌し、リキッドレシーバ７内に冷凍機油や被洗浄物を残存させないようにして、洗浄運転終了後の通常運転時において、これら冷凍機油や被洗浄物の残存により誘発させる不具合を防止することができる。尚、本実施形態の構成では、バイパス管と弁により簡易に構成されるものであり、既存の空調機の回路を踏襲したままにして適用することができるものであるが、上記構成のほか、リキッドレシーバ７に回転軸に複数の攪拌羽根を備えてなる攪拌装置を設ける構成等、単純な構成のものであってもよい。
【００３９】
（６）第六の実施形態
本実施形態は、図６に示す冷媒回路構成により行われるものである。即ち、前記四方弁８を暖房時冷媒流路設定とした際における、四方弁８から室内機３０へ冷媒を流す室外機配管８２と、同じく前記四方弁８を暖房時冷媒流路設定とした際における、室内機からリキッドレシーバ７へ冷媒を流す室外機配管８１と、を結ぶ第五冷媒バイパス管７５を設けるとともに、該第五冷媒バイパス管７５に第五冷媒バイパス弁６５を設け、室外熱交換器５から冷媒蒸発熱供給器（エンジン廃熱回収器４）へ冷媒を流す室外機配管８９に、暖機用膨張弁２３を設けた構成とするものである。そして、以上の構成において、前記四方弁８を暖房時冷媒流路設定とするとともに、室外機配管にて冷媒を循環させる流路設定とし、四方弁８、第五冷媒バイパス弁６５、室外熱交換器５、暖機用膨張弁２３、冷媒蒸発熱供給器（エンジン廃熱回収器４）、アキュムレータ６の順に冷媒を循環させる暖機運転モードを実行するものである。本実施形態の目的とするところは、第四又は第五の実施形態における、四方弁８を暖房時冷媒流路設定として既設配管２０の洗浄運転を行なう前段階にて、四方弁８を暖房時冷媒流路設定として冷媒を循環させる「暖機運転」を行なうことにより、（１）洗浄運転開始前に、圧縮機２より吐出する高温高圧ガス冷媒の温度を定常状態とし、さらに、この高温高圧ガス冷媒とともに既設配管２０へ流入する冷凍機油の温度を上昇させて上記洗浄性を高めることにより、洗浄運転の開始直後から確実に既設配管２０の洗浄を行なうこと、また、（２）冷媒蒸発熱供給器（エンジン廃熱回収器４）にて十分な熱量を確保し、既設配管２０を通過後の冷媒を確実に蒸発させ、アキュムレータ６での気液分離を適確に行なうこと、さらには、（３）暖機運転後、四方弁８の設定を切換えることなく、洗浄運転に切換える、つまりは、冷媒の流れ方向を変更せずに洗浄運転に切換えることで、冷媒の流れ方向の変更に伴うエネルギーロスを発生させないことである。
【００４０】
本実施形態は、第四又は第五の実施形態で、四方弁８を暖房時冷媒流路設定として洗浄する場合、即ち、圧縮機２より吐出した高温高圧ガス冷媒を、室外熱交換器５を通さずに、室外機配管８２より既設配管２０へ流入させて洗浄を行なう場合に適用されるものであり、洗浄運転の前段階において、第一開閉弁１７及び第二開閉弁１８を閉じ、第二冷媒バイパス弁６２を閉じ、暖房用膨張弁２１を開くとともに、四方弁８を暖房時冷媒流路設定とし、第五冷媒バイパス弁６５を開き、エンジン３、圧縮機２を運転して、室外機１内で冷媒を循環させる。この際の冷媒の循環について説明すると、圧縮機２を吐出した高温高圧ガス冷媒は、四方弁８より室外機配管８２へ流れるが、第一開閉弁１７は閉じているため、冷媒は、途中で分岐する第五冷媒バイパス管７５から室外機配管８１へ流れ、第二開閉弁１８が閉じているため、リキッドレシーバ７へ流入し、室外機配管７２’・７９を介して室外機配管８１を通って室外熱交換器５を通過後、暖機用膨張弁２３にて所定の圧力、即ち、エンジン廃熱回収器４で蒸発し得る圧力に減圧後、エンジン廃熱回収器４にて蒸発してアキュムレータ６へ流入し、再び圧縮機２に吸入される。以上の暖機運転を所定時間行なった後、第一開閉弁１７及び第二開閉弁１８を開くとともに、第五冷媒バイパス弁６５を閉じ、暖房用膨張弁２１を閉じることにより、四方弁８から高温高圧ガス冷媒を既設配管２０へ流入することで、上述した既設配管２０の洗浄運転を行なうのである。
【００４１】
以上の暖機運転を行なうことで、洗浄運転開始直後から、確実に既設配管２０の洗浄、アキュムレータ６での気液分離が行なえる。また、この暖機運転の終了後、洗浄運転に切換わる際には、四方弁８の切換えが行なわれないので、冷媒の流れ方向の変更に伴うエネルギーロスが発生することがなく、エネルギー効率のよい洗浄運転を行なうことができる。尚、上記暖機運転では、第二冷媒バイパス弁６２を閉じる一方、暖房用膨張弁２１を開くことにより、室外熱交換器５を通過させる流路設定としたが、この設定とは逆の設定、即ち、第二冷媒バイパス弁６２を開く一方、暖房用膨張弁２１を閉じることにより、第二冷媒バイパス管７２を通じさせ室外熱交換器５をバイパスさせる流路設定としてもよい。この場合には、暖機用膨張弁２３で行なうところの圧力制御を第二冷媒バイパス弁６２により行なう。
【００４２】
（７）第七の実施形態
本実施形態は、上記第一から第六の実施形態において、全量の内の一部の冷媒がオイルセパレータ１０をバイパスする回路を形成することにより、オイルセパレータ１０にて冷凍機油（合成油）の一部を敢えて分離させずに、冷媒中の冷凍機油（合成油）の含有量を多くした上で既設配管２０を洗浄することにより、既設配管２０内の洗浄をより確実に、効率よく行なおうとするものである。具体的には、図１、図３〜図６に示すごとく、圧縮機２と四方弁８とを結ぶ室外機配管７７に、オイルセパレータ１０を直列に接続して設ける（オイルセパレータ１０を必ず通過させるように接続する）とともに、該オイルセパレータ１０をバイパスさせるべく、オイルセパレータ１０の外部において、オイルセパレータ１０の吸入側と吐出側の配管を結ぶオイルセパレータバイパス管８８を設け、オイルセパレータ１０の吸入側の配管と、オイルセパレータバイパス管８８の接続部にオイルセパレータバイパス三方弁５０を設ける構成とするものである。以上の構成にて、オイルセパレータバイパス三方弁５０の開閉（ポートの切換え）をコントローラ２５により制御する、つまりは、洗浄運転時ではオイルセパレータバイパス管８８を通過させる側にオイルセパレータバイパス三方弁５０を切換えてオイルセパレータ１０をバイパスさせることにより、既設配管２０に冷凍機油の含有量の多い冷媒が供給されるようになって、既設配管２０内の洗浄をより確実に、効率よく行なうことができるようになる。尚、オイルセパレータバイパス三方弁５０については、分流式として、完全にオイルセパレータ１０をバイパスする構成、又は、混合式として、一部の冷媒をバイパスさせる構成のいずれの構成であってもよく、特に限定されるものでない。
【００４３】
【発明の効果】
本発明は以上のごとく構成したので、次のような効果を奏するのである。
空調機の施工時において、既設配管の洗浄を可能とする空調機であって、圧縮機（２）の吐出側に配置されるオイルセパレータ（１０）の出口側と、圧縮機（２）の吸入側を結ぶ第一冷媒バイパス管（７１）を設け、該第一冷媒バイパス管（７１）に第一冷媒バイパス弁（６１）を設け、冷媒回路にて新冷媒として使用される圧縮機用の冷凍機油を、被洗浄物である従来冷媒（ＣＦＣ系冷媒）の冷媒回路の圧縮機に用いられる鉱油からなる冷凍機油に対して相溶性を具備するＰＶＥ（ポリビニールエーテル）などの合成油を使用し、空調機の施工時の所定時間、前記第一冷媒バイパス弁（６１）を開いて、第一冷媒バイパス管（７１）より吐出冷媒を圧縮機（２）の吸入側にバイパスし、圧縮機（２）を吐出した後の冷媒の一部を再圧縮させ、吐出圧力を所定値よりも大とすることで、新冷媒中に含まれる合成油よりなる冷凍機油の温度上昇を図り、被洗浄物に対する冷凍機油の洗浄性の向上を図るので、圧縮機にて冷媒を再圧縮させることで、より高圧高温の状態で既設配管内に冷媒を通過させ、この冷媒中に含まれる冷凍機油（合成油）を温度が高い状態（相溶性の高い状態）、即ち、高い洗浄性を持った状態として、冷媒とともに被洗浄物を管内壁より剥離させることで、既設配管の洗浄を確実に行なうことができる。
また、この既設配管の洗浄は、従来行なわれていた専用の洗浄装置によらず、新設する空調機自体で行なうことができる。
【００４４】
また、前記第一冷媒バイパス配管より圧縮機の吸入側の冷媒配管に高温高圧冷媒を供給して、圧縮機の冷媒吐出圧力を所定値よりも大に維持しつつ所定時間既設配管内に冷媒を循環させるとともに、既設配管を通過後の冷媒を冷媒蒸発熱供給器にて蒸発させるので、より高圧高温の状態で既設配管内に冷媒を通過させ、この冷媒中に含まれる冷凍機油（合成油）を温度が高い状態（相溶性の高い状態）、即ち、高い洗浄性を持った状態として、冷媒とともに被洗浄物を管内壁より剥離させることで、既設配管の洗浄を確実に行なうことができる。
【図面の簡単な説明】
【図１】本発明を適用したエンジンヒートポンプの冷媒回路図である。
【図２】制御装置及び作動装置類の構成を示すブロック図である。
【図３】既設配管の洗浄を行う第二の実施形態の構成を示す図である。
【図４】同じく第三の実施形態の構成を示す図である。
【図５】同じく第五の実施形態の構成を示す図である。
【図６】同じく第六の実施形態の構成を示す図である。
【図７】冷凍機油（合成油）と被洗浄物の相溶性を示す図である。
【図８】冷凍機油の相溶性の大小と温度の関係を示したグラフである。
【符号の説明】
２圧縮機
４冷媒蒸発熱供給器
５室外熱交換器
６アキュムレータ
８四方弁
１０オイルセパレータ
２１暖房用膨張弁
７１第一冷媒バイパス管[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a configuration of an air conditioner specialized in the cleaning ability of existing pipes performed at the time of construction of the air conditioner, and a method for cleaning existing pipes by the air conditioner.
[0002]
[Prior art]
In conventional air conditioners, chlorinated refrigerants (hereinafter referred to as “conventional refrigerants”) such as CFC (chlorofluorocarbon) and HCFC (hydrochlorofluorocarbon) have been used. In order to destroy the ozone layer in the stratosphere, chlorine contained in HFC (hydrofluorocarbon) (hereinafter referred to as “new refrigerant”), which is a non-chlorine refrigerant, has been used instead. With the replacement of this new refrigerant, when installing an air conditioner (outdoor unit / indoor unit) while using the existing piping of the building, the refrigeration oil used in the compressor is different, so the existing piping A cleaning operation for removing the residue of the refrigeration oil for the conventional refrigerant is performed. This cleaning operation is performed using a dedicated pipe cleaning device in a stage before installing the air conditioner.
[0003]
In addition, the object to be cleaned in this cleaning operation, that is, the residue such as the refrigerating machine oil for the conventional refrigerant does not dissolve in the new refrigerant (incompatibility between the new refrigerant and the object to be cleaned shown in FIG. 7). Is based on the theory that "the object to be cleaned attached to the wall surface of the pipe due to the turbulence of the refrigerant flow is stripped off", and the refrigerant is made to flow in a liquid single-phase or gas single-phase by flowing the refrigerant in a gas-liquid two-phase flow. The turbulence of the flow was increased and the existing piping was cleaned. As described above, conventionally, cleaning is performed by paying attention to the state of the refrigerant flowing in the existing pipe. In the above-described pipe cleaning apparatus, the refrigerant is previously washed in the pipe in order to flow the refrigerant in the existing pipe in a gas-liquid two-phase state. The refrigerant circuit was designed to be in a gas-liquid two-phase state in the device.
[0004]
[Problems to be solved by the invention]
However, the existing pipes described above are intricately stretched inside and outside the building, and there are many branch points and corners, so that the pressure fluctuation of the refrigerant is likely to occur. Thus, it can be said that it is practically extremely difficult to flow the refrigerant that has been in the gas-liquid two-phase state in the cleaning device through the entire section of the existing piping while maintaining the gas-liquid two-phase state. It is extremely difficult in practice to accurately grasp the state of the refrigerant flowing in the pipe. For this reason, it can be said that it is difficult to create a situation where cleaning is performed in a completely gas-liquid two-phase state.
[0005]
Therefore, without depending on the phase of the liquid or gas of the refrigerant flowing in the existing piping, the means for effectively cleaning the existing piping is examined by reliably removing the object to be cleaned, The inventors of the present invention have used a compressor refrigerating machine oil made of a synthetic oil such as PVE (polyvinyl ether) used in a refrigerant circuit using a new refrigerant, and a conventional refrigerating machine oil for a refrigerant that is the above-mentioned object to be cleaned. Attention was paid to the compatibility (compatibility between the refrigerating machine oil (synthetic oil) and the object to be cleaned shown in FIG. 7). The graph shown in FIG. 8 is composed of refrigeration oil made of synthetic oil used in the compressor of the refrigerant circuit of the new refrigerant (HFC refrigerant) and mineral oil used in the compressor of the refrigerant circuit of the conventional refrigerant (CFC refrigerant). It is the graph which showed the size of the compatibility of refrigerating machine oil, and the relationship of the temperature of the refrigerating machine oil which consists of synthetic oils. From this graph, it can be seen that the higher the temperature of the refrigerating machine oil composed of synthetic oil, the greater the compatibility between the two, and if the temperature of the refrigerating machine oil composed of this synthetic oil is raised, it can flow through the existing piping. It is possible to carry out washing after reliably dissolving the washed product (mineral oil).
[0006]
Here, in the refrigerant circuit of the conventional general air conditioner, the refrigeration oil (synthetic oil) for the new refrigerant is separated by the oil separator and recirculated to the compressor again. In this oil separator, Because of the problem that the refrigeration oil cannot be completely separated, the refrigeration oil that circulates in the outdoor unit piping and flows into the accumulator is taken in from the oil suction hole provided in the U-shaped pipe, and is again sucked into the compressor. Yes. Thus, paying attention to the fact that a small amount of refrigerating machine oil (synthetic oil) is contained in the refrigerant after passing through the oil separator, this small amount of refrigerating machine oil (synthetic oil) is allowed to effectively act on the cleaning of existing piping. The means were examined.
[0007]
The present invention has been completed by conducting a study while paying attention to the relationship between the temperature and compatibility of the two refrigerating machine oils described above, and a small amount of refrigerating machine oil (synthetic oil) contained in the refrigerant, By passing through the existing piping as a high temperature state, the refrigerating machine oil (object to be cleaned) made of mineral oil is dissolved in the refrigerating machine oil (synthetic oil), and the peelability from the pipe wall of the object to be cleaned is improved. In addition to improving the cleanability of the existing air-conditioner, the existing air-conditioner itself is intended to clean the existing piping without using a dedicated cleaning device.
[0008]
[Means for Solving the Problems]
The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.
An air conditioner capable of cleaning existing piping during construction of the air conditioner, the outlet side of the oil separator (10) disposed on the discharge side of the compressor (2), and the suction of the compressor (2) The first refrigerant bypass pipe (71) connecting the two sides is provided, the first refrigerant bypass pipe (71) is provided with the first refrigerant bypass valve (61), and the compressor is used as a new refrigerant in the refrigerant circuit. The machine oil used is a synthetic oil such as PVE (polyvinyl ether) that is compatible with refrigerating machine oil made of mineral oil used in the compressor of the refrigerant circuit of the conventional refrigerant (CFC refrigerant) that is the object to be cleaned. The first refrigerant bypass valve (61) is opened for a predetermined time during construction of the air conditioner, and the discharged refrigerant is bypassed from the first refrigerant bypass pipe (71) to the suction side of the compressor (2). 2) Recompress some of the refrigerant after discharging The discharge pressure than a predetermined value by a large, achieving an increase in the temperature of the refrigerating machine oil consisting of synthetic oil contained in the new refrigerant, to improve the cleaning of the refrigerating machine oil for the object to be cleaned Is.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a refrigerant circuit diagram of an engine heat pump to which the present invention is applied, FIG. 2 is a block diagram showing the configuration of a control device and operating devices, and FIG. 3 is a diagram showing the configuration of a second embodiment for cleaning existing piping. 4 is a diagram showing the configuration of the third embodiment, FIG. 5 is a diagram showing the configuration of the fifth embodiment, FIG. 6 is a diagram showing the configuration of the sixth embodiment, and FIG. FIG. 8 is a graph showing the relationship between the compatibility of the machine oil (synthetic oil) and the object to be cleaned, and FIG.
[0010]
The refrigerant circuit diagram shown in FIG. 1 shows an embodiment of a configuration provided in an outdoor unit 1 of an engine heat pump that drives a compressor 2 with an engine 3. In the following description, the engine heat pump outdoor unit 1 will be described as an example, but the present invention is not limited to the “engine heat pump” but can be applied to general air conditioners such as an “electric air conditioner”.
[0011]
In FIG. 1, an outdoor unit 1 of an air conditioner is installed outside a building or the like that requires air conditioning, and includes a compressor 2, an engine waste heat recovery unit 4 as a refrigerant evaporating heat supply unit, and outdoor heat exchange. A refrigerant circuit is formed by devices such as the vessel 5, the accumulator 6, the liquid receiver 7, and the like, the four-way valve 8, the outdoor unit pipes 81 and 82, and the valves / pipe / filters such as the oil separator 10.
[0012]
Here, the oil separator 10 separates the refrigerating machine oil (synthetic oil) for the new refrigerant and recirculates it to the compressor 2 again. In this oil separator 10, the refrigerating machine oil (synthetic oil) is completely removed. Since it cannot be separated, the refrigerant after passing through the oil separator 10 contains a small amount of refrigerating machine oil (synthetic oil).
[0013]
The compressor 2 is configured to drive an internal rotating body by connecting / disconnecting driving of the engine 3 by the clutch 33. The clutch 33 is configured by an electromagnetic clutch, and the connecting / disconnecting operation of the outdoor unit 1 is performed. It is controlled by the controller 25 that controls it. The engine waste heat recovery unit 4 is provided on the suction side of the compressor 2, that is, on the upstream side of the compressor 2 in the flow of refrigerant sucked into the compressor 2. The engine waste heat recovery device 4 is applied as a refrigerant evaporative heat supply device when the present invention is implemented by an engine heat pump. When implemented in an electric air conditioner, the engine waste heat is collected by an electric heater or the like. The function equivalent to that of the recovery device 4 is substituted.
[0014]
The outdoor unit 1 includes a radiator 11, a cooling water three-way valve 12, a thermostat 13, a cooling water pump 14, an exhaust gas heat exchanger 15, and a cooling water pipe 16, and constitutes an engine cooling water circuit together with the engine 3. is doing.
[0015]
As shown in FIG. 1, a discharge pipe 19 provided with a recovery valve 28 is connected to the bottom of the accumulator 6, and a recovery device 27 is provided on the discharge port side of the discharge pipe 19. Further, a U-shaped tube 83 is provided in the accumulator 6, and the refrigerating machine oil of the compressor 2 that has not been separated by the oil separator 10 is supplied to the compressor 2 on the lower wall surface of the U-shaped tube 83 as described above. An oil suction hole 24 for inhaling is provided.
[0016]
The outdoor unit piping 81 connecting the outdoor heat exchanger 5 and the liquid receiver 7 is provided with a heating expansion valve 21, and the pressure control of the refrigerant is performed immediately before flowing into the outdoor heat exchanger 5 during heating. I try to do it.
[0017]
Further, one end of the U-shaped tube 83 of the accumulator 6 opens upward and opens into the upper space in the container 40 of the accumulator 6, and the other end of the U-shaped tube 83 is connected to the main discharge tube 84 on the suction side of the compressor 2. The main discharge pipe 84 is provided with a discharge pipe electromagnetic opening / closing valve 29. Further, in the main discharge pipe 84, one end of the sub discharge pipe 85 is connected to the compressor 2 side (downstream side) from the place where the discharge pipe electromagnetic on-off valve 29 is installed. The other end is inserted into the container 40 of the accumulator 6 and communicates with the upper inner space of the container 40. The main discharge pipe 84 and the sub discharge pipe 85 are connected to pipes 10a and 10b communicating with the bottom of the oil separator 10, respectively, and the refrigerating machine oil separated by the oil separator 10 is supplied to the main discharge pipe. It flows into the pipe 84 and the sub-discharge pipe 85 and is supplied to the compressor 2 again. The sub-discharge pipe 85 is connected to a gas refrigerant return pipe 86 that communicates with the upper internal space of the recovery device 27, and a return pipe electromagnetic opening / closing valve 94 is provided in the gas return pipe 86.
[0018]
A first refrigerant bypass pipe 71 provided with a first refrigerant bypass valve 61 is connected to the outdoor unit pipe 77 connecting the oil separator 10 and the four-way valve 8, and the oil separator 10 is discharged from the compressor 2. Part of the high-temperature and high-pressure gas refrigerant that has passed is guided to a main discharge pipe 84 that is a pipe on the suction side of the compressor 2.
[0019]
In contrast to the configuration of the outdoor unit 1 described above, the indoor unit 30 is installed in a building or the like that requires air conditioning, and includes an indoor heat exchanger 31, an indoor unit fan 30f, an indoor heat exchanger expansion valve 32, and the like. And is connected to the existing pipe 20. In addition, in the figure, although it is set as the structure which installed the one indoor unit 30, it does not specifically limit about the number, The structure which arrange | positions two or more indoor units may be sufficient.
[0020]
FIG. 2 shows the configuration of a control device that controls the operation of the engine heat pump and the operating devices. The controller 25 that is a control device includes a heating expansion valve 21, a recovery valve 28, and a discharge pipe that are electromagnetic valves. The electromagnetic on-off valve 29, the return pipe electromagnetic on-off valve 94, the indoor heat exchanger expansion valve 32, and the cooling water three-way valve 12 are connected to control the opening and closing of these valves. The engine 3 is controlled in number of revolutions, the flow of the four-way valve 8 is switched, and the clutch 33 is connected / disconnected. In addition to these, according to the embodiment of the refrigerant circuit described later, as shown in FIG. 2, the controller 25 includes first to fifth refrigerant bypass valves (61 to 65) composed of electromagnetic valves, and a cleaning expansion valve 22. The opening of the warm-up expansion valve 23 and the oil separator bypass three-way valve 50 is adjusted, and the detection value of the high-pressure sensor 66 that detects the refrigerant pressure after discharging the compressor 2 is input.
[0021]
Then, as shown in FIG. 1, the outdoor unit 1 and the indoor unit 30 described above are communicated with each other through the existing pipe 20 by the first on-off valve 17 and the second on-off valve 18, and a new refrigerant is supplied to the existing pipe 20. While being circulated, the controller 25 controls the four-way valve 8 to change the flow path of the circulating refrigerant so that the heating operation and the cooling operation are performed.
[0022]
The heating operation performed in the engine heat pump configured as described above will be described. As shown in FIG. 1, the refrigerant compressed by the compressor 2 has a four-way valve 8 switched in the heating direction as a state of high-temperature high-pressure superheated steam. Via the outdoor unit pipe 82, the first on-off valve 17 passes through the existing pipe 20 and is sent to the indoor heat exchanger 31. In the indoor heat exchanger 31, heat is released from the refrigerant in the high-temperature and high-pressure superheated vapor state to the indoor air, and the refrigerant enters a high-pressure liquid state. This heat release causes room heating.
[0023]
The refrigerant in the high-pressure liquid state passes through the second on-off valve 18 and returns to the outdoor unit piping 81, and then rapidly expands in the heating expansion valve 21 after passing through the liquid receiver 7 and the outdoor unit piping 72 ′ and 79. Thus, the refrigerant becomes a low-temperature and low-pressure vapor state, and while passing through the outdoor heat exchanger 5, heat is obtained from the outside air to become a heated vapor. The heated steam evaporates in the engine waste heat recovery device 4 through the four-way valve 8 to become a gas refrigerant, flows into the accumulator 6, is sucked into the compressor 2, and repeats the above operation.
[0024]
Next, the cooling operation will be described. As shown in FIG. 1, the refrigerant compressed by the compressor 2 becomes a high-temperature high-pressure supersaturated vapor refrigerant (high-temperature high-pressure gas refrigerant) and passes through the oil separator 10 and the four-way valve 8. It is pumped to the outdoor heat exchanger 5. The refrigerant is cooled by the outdoor fan 5f while passing through the cooling fins of the outdoor heat exchanger 5, and is liquefied from the high-temperature high-pressure superheated state to the high-pressure liquid phase state.
[0025]
The refrigerant that has been in a high-pressure liquid phase state in the outdoor heat exchanger 5 is separated into gas and liquid by the liquid receiver 7, passes through the outdoor unit pipe 81, and passes through the existing pipe 20 connected to the second opening / closing valve 18. , Sent to the indoor unit 30. In this indoor unit 30, after the pressure is reduced by the indoor heat exchanger expansion valve 32, the indoor heat exchanger 31 absorbs heat from the indoor air and evaporates it to cool the indoor air, and the indoor unit fan 30f Thus, the air is blown into the room to bring about a cooling effect. Thereafter, the refrigerant evaporated in the indoor heat exchanger 31 passes through the existing pipe 20, passes through the first on-off valve 17, returns to the accumulator 6 through the four-way valve 8, and is compressed as a gas refrigerant. Inhaled by the machine 2, the above operation is repeated.
[0026]
And by setting it as the said structure, it becomes the structure which can wash the existing piping 20 with engine heat pump itself, Specifically, in the case of construction of an engine heat pump, cooling operation or heating operation is performed. Then, the refrigerant is passed through the existing pipe 20, the object to be cleaned attached to the existing pipe 20 is peeled off with the refrigerant and the refrigerating machine oil (synthetic oil) contained in the refrigerant, and the object to be cleaned together with the refrigerant is removed from the engine. It is made to flow to the waste heat recovery unit 4 and the engine waste heat recovery unit 4 evaporates the refrigerant to be a gas refrigerant, while the object to be cleaned is left in a liquid or solid (insoluble matter) state and flows into the accumulator 6. The object to be cleaned that has flowed into the accumulator 6 is discharged from the discharge pipe 19 to the recovery device 27. As described above, the object to be cleaned is separated by the accumulator 6 and the object to be cleaned is recovered by the recovery device 27. The engine heat pump itself cleans the existing pipe 20 without using the dedicated pipe cleaning device. It is set as the structure which performs.
[0027]
The above is the outline of the configuration of the air conditioner (engine heat pump) to which the present invention is applied and the pipe cleaning by the air conditioner itself. Hereinafter, the details of the configuration of the air conditioner and the effects based thereon will be described.
[0028]
In the present invention, as described above, pipe cleaning is performed by the air conditioner (engine heat pump) itself without using a dedicated pipe cleaning device. And in order to perform this piping washing | cleaning more reliably, by making the pressure of the refrigerant | coolant which flows through the existing piping 20 into a high pressure, in other words, maintaining the refrigerant | coolant discharge pressure of the compressor 2 larger than a predetermined value, The temperature of refrigeration oil (synthetic oil) and the temperature of refrigeration oil (synthetic oil) are increased as the refrigerant temperature increases, thereby improving the compatibility of refrigeration oil (synthetic oil) and the object to be cleaned (mineral oil). The object to be cleaned is easily peeled off from the tube wall, that is, the cleaning can be performed by increasing the cleaning power by the circulating refrigerant including the refrigerating machine oil (synthetic oil). Hereinafter, an embodiment for increasing the pressure of the refrigerant flowing in the existing pipe 20 will be described.
[0029]
(1) First embodiment
This embodiment is performed by the refrigerant circuit configuration shown in FIG.
That is, the outdoor heat exchanger 5, the compressor 2, the oil separator 10 that separates the refrigeration oil in the refrigerant discharged from the compressor 2, the four-way valve 8 that switches the refrigerant flow path during cooling and heating, An air conditioner (this specification) including a liquid receiver 7, a refrigerant evaporative heat supply device (in this specification, an engine waste heat recovery device 4), an accumulator 6, a heating expansion valve 21, and a refrigerant pipe communicating these components. In the engine heat pump, the first refrigerant bypass pipe connecting the outdoor unit pipe 77 connecting the oil separator 10 and the four-way valve 8 and the main discharge pipe 84 (or sub discharge pipe 85) on the suction side of the compressor 2. 71, and the first refrigerant bypass pipe 61 is provided in the first refrigerant bypass pipe 71. The object of the present embodiment is that the high-temperature and high-pressure gas refrigerant discharged from the compressor 2 and passed through the oil separator 10 passes through the first refrigerant bypass pipe 71 and is connected to the refrigerant pipe on the suction side of the compressor 2, that is, the main By bypassing the discharge pipe 84, the refrigerant pressure sucked into the compressor 2 is increased to increase the refrigerant pressure discharged from the compressor 2, and the high-pressure refrigerant passes through the existing pipe 20. And cleaning the existing pipe 20 together with the high-temperature refrigerating machine oil (synthetic oil) contained in the refrigerant. In other words, a higher-pressure gas refrigerant is discharged from the compressor 2, and the temperature of the refrigerating machine oil (synthetic oil) contained in the refrigerant is increased based on the high temperature of the refrigerant accompanying the increase in the refrigerant pressure. The improvement of the washing | cleaning property of the refrigerating machine oil (synthetic oil) with respect to a to-be-cleaned object is aimed at.
[0030]
In this configuration, after the refrigerant discharged from the compressor 2 passes through the oil separator 10, a part of the refrigerant is directly sent to the four-way valve 8, while the rest depends on the opening of the first refrigerant bypass valve 61. It is sent to the main discharge pipe 84 on the suction side of the compressor 2 through the bypass pipe 71 and is again sucked into the compressor 2 and recompressed, and then discharged from the compressor 2 in a higher pressure state. That is, a higher pressure refrigerant is discharged from the compressor 2 by recompressing a part of the refrigerant once discharged from the compressor 2. Here, the opening degree of the first refrigerant bypass valve 61 is controlled by the controller 25 so that the detected value of the refrigerant discharge pressure by the high-pressure sensor 66 after discharge of the compressor 2 is maintained larger than a predetermined value. It is. The predetermined value of the refrigerant discharge pressure here is determined by a test and stored in the controller 25 in advance. The refrigerant discharged from the compressor 2 flows from the four-way valve 8 via the outdoor heat exchanger 5 to the indoor unit 30 (in the case of cooling refrigerant flow path setting), or directly flows from the four-way valve 8 to the indoor unit 30. When the refrigerant flow path is set for heating, the pipe inner wall is washed by passing through the existing pipe 20, and also when returning from the indoor unit 30 to the outdoor unit 1, the pipe inner wall passes through the existing pipe 20. Wash. Here, the refrigerant passing through the existing pipe 20 passes through the existing pipe 20 in a higher pressure and high temperature state than the refrigerant not recompressed by the compressor 2 described above, and is included in this refrigerant. Refrigeration machine oil (synthetic oil) can be allowed to flow in a high temperature state, that is, in a state having high detergency, and the object to be cleaned (mineral oil) adhering to the inner wall of the existing pipe 20 is securely peeled off. In addition, the cleaning can be completed in a short time due to its high detergency.
[0031]
(2) Second embodiment
This embodiment is performed by the refrigerant circuit configuration shown in FIG. That is, in the refrigerant pipe of the outdoor unit 1 of the air conditioner, the expansion pipes 22 and 22 'for controlling the pressure of the refrigerant are provided in the refrigerant pipe through which the refrigerant flows from the four-way valve 8 to the indoor unit 30. Is. The purpose of this embodiment is based on the configuration of the first embodiment, and immediately before the pressure of the high-pressure refrigerant discharged from the compressor 2 flows into the existing pipe 20, the cleaning expansion valve 22. -Control by 22 'allows the pressure-controlled refrigerant to flow into the existing pipe 20 and enables pipe cleaning according to the pipe inner diameter and length of the existing pipe 20, and the recompression causes excessive pressure. In this case, the purpose is to prevent damage to the existing pipe 20 by reducing the pressure immediately before flowing into the existing pipe 20, in other words, to control the refrigerant pressure to a value suitable for cleaning (allowable maximum pressure). To do. In the configuration shown in FIG. 3, the cleaning expansion valve 22 provided in the outdoor unit pipe 81 that flows the refrigerant discharged from the compressor 2 and passed through the four-way valve 8 and the outdoor heat exchanger 5 to the existing pipe 20 is: The cleaning expansion valve 22 controls the pressure of the refrigerant that is about to flow into the existing pipe 20, and functions when the four-way valve 8 is set to the cooling refrigerant flow path setting for the cleaning operation. On the other hand, in the case of performing the cleaning operation with the four-way valve 8 set as the refrigerant flow channel during heating, the cleaning unit provided in the outdoor unit pipe 82 that discharges the refrigerant from the compressor 2 and passes the refrigerant through the four-way valve 8 directly to the existing pipe 20. The expansion valve 22 'is made to function.
[0032]
In the present embodiment, the case of performing the washing operation with the four-way valve 8 set as the refrigerant flow path during cooling will be described. The high-temperature and high-pressure gas refrigerant discharged from the compressor 2 during cooling passes through the four-way valve 8 and then performs outdoor heat exchange. After the heat is dissipated in the vessel 5 to become a high-temperature and high-pressure liquid refrigerant, pressure control is performed by the cleaning expansion valve 22 immediately before flowing into the existing pipe 20 from the outdoor unit pipe 81, and the refrigerant is passed through the existing pipe 20 in the direction of arrow A It is to be washed by flowing it. Although the pressure is reduced when passing through the cleaning expansion valve 22, it is a high-temperature and high-pressure liquid refrigerant until it passes through the cleaning expansion valve 22. Therefore, the refrigerating machine oil (synthetic oil) contained in the refrigerant has a high temperature. It is a state, it flows in into the existing piping 20 in the state with high detergency, and the existing piping 20 can be wash | cleaned reliably.
[0033]
Further, in the present embodiment, the case where the washing operation is performed with the four-way valve 8 set as the refrigerant flow path during heating will be described. After the high-temperature and high-pressure gas refrigerant discharged from the compressor 2 during cooling passes through the four-way valve 8, the outdoor Immediately before flowing from the machine pipe 82 to the existing pipe 20, pressure is controlled by the cleaning expansion valve 22 ′, and the refrigerant is washed by flowing the refrigerant in the direction of the arrow B in the existing pipe 20. In the cleaning operation by this setting, the refrigerant discharged from the compressor 2 flows into the existing pipe 20 without passing through the outdoor heat exchanger 5, so that the refrigerant is not used as compared with the case of setting the cooling refrigerant flow rate. This is effective in that the existing pipe 20 can be circulated at a higher temperature.
[0034]
Further, by switching the four-way valve 8, the refrigerant flows in the existing pipe 20 in both directions indicated by the arrows A and B, whereby the path connecting the first on-off valve 17 and the indoor unit 30, the second on-off valve 18, Both paths of the path connecting the indoor unit 30 can be washed uniformly.
[0035]
(3) Third embodiment
This embodiment is performed by the refrigerant circuit configuration shown in FIG. In other words, an outdoor unit pipe 47 for flowing the refrigerant from the four-way valve 8 to the refrigerant evaporating heat supply unit (in this specification, the engine waste heat recovery unit 4) and a second refrigerant bypass pipe 72 connecting the liquid receiver 7 are provided. The second refrigerant bypass pipe 72 is provided with a second refrigerant bypass valve 62, and the outdoor unit piping 82 of the outdoor unit 1 on the downstream side of the four-way valve 8 in the refrigerant flow when the four-way valve 8 is in the heating refrigerant flow path setting. And a third refrigerant bypass pipe 73 connecting the outdoor heat exchanger 5 and the outdoor unit piping 81a between the heating expansion valve 21 and a third refrigerant bypass valve 63 in the third refrigerant bypass pipe 73. The configuration is provided. The purpose of this embodiment is that when performing the cleaning operation with the four-way valve 8 set as the cooling refrigerant flow path setting in the second embodiment having the configuration including the cleaning expansion valves 22 and 22 ′, The existing pipe 20 can be made to flow in the reverse direction, and the existing pipe 20 can be washed uniformly, that is, the direction of the refrigerant flowing through the existing pipe 20 can be switched to change the existing pipe 20 An object of the present invention is to prevent the cleaning performance from being deteriorated due to a decrease in the temperature of the refrigerant and the refrigerating machine oil (synthetic oil) in the process of flowing through the interior 20, and to clean the existing piping 20 more reliably. In the present embodiment, in a state where the first on-off valve 17 and the second on-off valve 18 are opened, first, the third refrigerant bypass valve 63 is closed and the heating expansion valve 21 is opened, so that the outdoor unit pipe 81 side is opened. The refrigerant is set to flow, the pressure is controlled by the cleaning expansion valve 22, and the refrigerant is caused to flow into the existing pipe 20 from the second on-off valve 18. To wash for a predetermined time. After that, the cleaning expansion valve 22 ′ is closed and the heating expansion valve 21 is closed, while the pressure is controlled by the third refrigerant bypass valve 63, the refrigerant is supplied to the third refrigerant bypass pipe 73, and the first opening / closing is performed. The refrigerant is caused to flow from the valve 17 into the existing pipe 20, and in the existing pipe 20, the refrigerant is caused to flow in the direction of arrow B in the drawing to perform cleaning for a predetermined time. As described above, both paths of the path connecting the first on-off valve 17 and the indoor unit 30 and the path connecting the second on-off valve 18 and the indoor unit 30 by flowing the refrigerant bidirectionally in the existing pipe 20 are provided. It becomes possible to wash | clean in the state close | similar to the same conditions as much as possible, and the existing piping 20 can be wash | cleaned uniformly.
[0036]
Furthermore, in the present embodiment, while the four-way valve 8 is set to the cooling flow path, the refrigerant is passed through the third refrigerant bypass pipe 73 to cause the refrigerant to flow in the direction of the arrow B in the existing pipe 20, and the indoor unit The refrigerant that has returned to the outdoor unit 1 through the second opening / closing valve 18 from the 30 side is temporarily stored in the liquid receiver 7 (the heating expansion valve 21 is closed), and then the second refrigerant bypass pipe 72 from the liquid receiver 7. '· 72 is used to construct a circuit through which the engine waste heat recovery unit 4 passes, and the engine waste heat recovery unit 4 evaporates the refrigerant and is cleaned with the refrigerant. Is allowed to flow into the accumulator 6 as a liquid or solid (insoluble matter) and can be separated by the accumulator 6. As described above, when the existing piping 20 is washed by passing through the third refrigerant bypass pipe 73, the refrigerant flow into the outdoor heat exchanger 5 is bypassed by passing through the second refrigerant bypass pipe 72. It is possible to prevent the object to be cleaned from adhering to the piping of the outdoor heat exchanger 5.
[0037]
(4) Fourth embodiment
This embodiment is performed by the refrigerant circuit configuration shown in FIG. 3 or FIG. In other words, an outdoor unit pipe 47 for flowing the refrigerant from the four-way valve 8 to the refrigerant evaporating heat supply unit (in this specification, the engine waste heat recovery unit 4) and a second refrigerant bypass pipe 72 connecting the liquid receiver 7 are provided. The second refrigerant bypass valve 62 is provided in the second refrigerant bypass pipe 72. The object of the present embodiment is that, in the first or second embodiment, the four-way valve 8 is set as a refrigerant flow channel for heating, and the high-temperature and high-pressure gas refrigerant passes through the outdoor unit pipe 82 from the first on-off valve 17. By letting it flow into 20, the existing piping 20 is washed more reliably by washing the existing pipe 20 in a high temperature state with high washing performance together with the refrigerant in the high-temperature and high-pressure gas refrigerant. In the present embodiment, the high-temperature and high-pressure gas refrigerant discharged from the compressor 2 is allowed to flow through the outdoor unit pipe 82 in a state in which the heating expansion valve 21 is fully closed while the four-way valve 8 is set to the heating flow path setting. It passes through one open / close valve 17 and flows into the existing pipe 20. In the existing pipe 20, the object to be cleaned is melted by high-temperature refrigeration oil (synthetic oil) and peeled off from the inner wall of the pipe, passes through the second on-off valve 18 together with the high-temperature high-pressure gas refrigerant, and flows into the outdoor unit pipe 81. , Temporarily stored in the liquid receiver 7. Then, the object to be cleaned is guided to the engine waste heat recovery unit 4 through the second refrigerant bypass pipes 72 'and 72 together with the refrigerant, whereby the object to be cleaned and the refrigerant are separated from each other by the accumulator 6. As described above, the pipe inner wall of the existing pipe 20 can be reliably washed by washing the existing pipe 20 with the refrigerating machine oil (synthetic oil) having a high washability contained in the high-temperature and high-pressure gas refrigerant. As in the latter stage of the third embodiment, the refrigerant containing the object to be cleaned bypasses the outdoor heat exchanger 5 and is guided to the accumulator 6, so that the inside of the pipe of the outdoor heat exchanger 5 for the object to be cleaned Adhesion to can be prevented.
[0038]
(5) Fifth embodiment
This embodiment is performed by the refrigerant circuit configuration shown in FIG. That is, the liquid receiver 7 is provided with stirring means for stirring the liquid in the liquid receiver 7, and the stirring means includes an outdoor unit pipe 77 for flowing a refrigerant from the compressor 2 to the outdoor heat exchanger 5, and A fourth refrigerant bypass pipe 74 that communicates with the liquid receiver 7 is provided, and a fourth refrigerant bypass valve 64 is provided in the fourth refrigerant bypass pipe 74. Further, the end opening of the fourth refrigerant bypass pipe 74 is arranged near the bottom of the liquid receiver 7. The purpose of this embodiment is that in the third and fourth embodiments, when the refrigerant or the like after washing is stored in the temporary liquid receiver 7, the liquid receiver 7 is connected to the bottom of the liquid receiver 7 through the fourth refrigerant bypass valve 64. By mixing the refrigerating machine oil and the object to be cleaned with the refrigerant by agitating the refrigerant or the like with the high-temperature and high-pressure gas refrigerant to be injected, the refrigerating machine oil and the object to be cleaned are allowed to flow through the second refrigerant bypass pipe 72 together with the refrigerant. That is, refrigeration oil and objects to be cleaned are not left in the receiver 7. In this embodiment, in the third and fourth embodiments, the liquid receiver 7 is opened by opening the fourth refrigerant bypass valve 64 when washing is performed by flowing the refrigerant in the direction of the arrow B in the existing pipe 20. A high-temperature high-pressure gas refrigerant is injected into the liquid, the refrigerant, the refrigerator oil, and the object to be cleaned in the liquid receiver 7 are agitated, and the refrigerant oil and the object to be cleaned floating on the upper surface of the refrigerant are mixed in the refrigerant. Further, the opening and closing of the fourth refrigerant bypass valve 64 may be any control of continuous opening control or intermittent opening control. As described above, the liquid receiver 7 is agitated so that the refrigerating machine oil and the object to be cleaned do not remain in the liquid receiver 7, and during the normal operation after the completion of the cleaning operation, Problems caused by remaining can be prevented. In addition, in the configuration of the present embodiment, it is simply configured by a bypass pipe and a valve, and can be applied while following the circuit of an existing air conditioner. The liquid receiver 7 may have a simple configuration such as a configuration in which a stirring device including a plurality of stirring blades is provided on the rotating shaft.
[0039]
(6) Sixth embodiment
This embodiment is performed by the refrigerant circuit configuration shown in FIG. That is, when the four-way valve 8 is set to the heating refrigerant flow path, the outdoor unit pipe 82 for flowing refrigerant from the four-way valve 8 to the indoor unit 30 and the four-way valve 8 is also set to the heating refrigerant flow path setting. In addition, a fifth refrigerant bypass pipe 75 connecting the indoor unit to the outdoor unit pipe 81 for flowing the refrigerant from the indoor unit to the liquid receiver 7 is provided, and a fifth refrigerant bypass valve 65 is provided in the fifth refrigerant bypass pipe 75 for outdoor heat exchange. The warm-up expansion valve 23 is provided in the outdoor unit pipe 89 that allows the refrigerant to flow from the cooler 5 to the refrigerant evaporative heat supply unit (engine waste heat recovery unit 4). In the above configuration, the four-way valve 8 is set to a heating-time refrigerant flow path setting and a flow path setting to circulate the refrigerant in the outdoor unit piping, and the four-way valve 8, the fifth refrigerant bypass valve 65, the outdoor heat exchange is set. The warm-up operation mode in which the refrigerant is circulated in the order of the unit 5, the warm-up expansion valve 23, the refrigerant evaporative heat supplier (engine waste heat recovery unit 4), and the accumulator 6 is executed. The object of the present embodiment is that the four-way valve 8 is heated in the stage before the cleaning operation of the existing pipe 20 is performed with the four-way valve 8 set as the heating refrigerant flow path setting in the fourth or fifth embodiment. By performing the “warm-up operation” for circulating the refrigerant as the refrigerant flow path setting, (1) the temperature of the high-temperature high-pressure gas refrigerant discharged from the compressor 2 is set to a steady state before the start of the cleaning operation, and this high-temperature high-pressure The temperature of the refrigerating machine oil that flows into the existing pipe 20 together with the gas refrigerant is increased to improve the cleaning performance, thereby reliably cleaning the existing pipe 20 immediately after the start of the cleaning operation, and (2) heat of refrigerant evaporation A sufficient amount of heat is secured by the supply device (engine waste heat recovery device 4), the refrigerant after passing through the existing pipe 20 is surely evaporated, and the gas-liquid separation in the accumulator 6 is performed appropriately. (3) Warm-up After switching, switching to the washing operation without switching the setting of the four-way valve 8, that is, switching to the washing operation without changing the refrigerant flow direction does not cause an energy loss due to the change in the refrigerant flow direction. That is.
[0040]
This embodiment is the fourth or fifth embodiment. When the four-way valve 8 is washed as the heating refrigerant flow path setting, that is, the high-temperature high-pressure gas refrigerant discharged from the compressor 2 is passed through the outdoor heat exchanger 5. This is applied when washing is performed by flowing into the existing pipe 20 from the outdoor unit pipe 82 without passing through, and the first on-off valve 17 and the second on-off valve 18 are closed before the cleaning operation. The two refrigerant bypass valve 62 is closed, the heating expansion valve 21 is opened, the four-way valve 8 is set to the heating refrigerant flow path, the fifth refrigerant bypass valve 65 is opened, the engine 3 and the compressor 2 are operated, and the outdoor The refrigerant is circulated in the machine 1. The circulation of the refrigerant at this time will be described. The high-temperature and high-pressure gas refrigerant discharged from the compressor 2 flows from the four-way valve 8 to the outdoor unit pipe 82. However, since the first on-off valve 17 is closed, the refrigerant Since the second on-off valve 18 is closed from the branched fifth refrigerant bypass pipe 75 to the outdoor unit pipe 81, it flows into the liquid receiver 7 and passes through the outdoor unit pipe 81 through the outdoor unit pipes 72 'and 79. After passing through the outdoor heat exchanger 5, the pressure is reduced to a predetermined pressure by the warm-up expansion valve 23, that is, a pressure that can be evaporated by the engine waste heat recovery unit 4, and then evaporated by the engine waste heat recovery unit 4. It flows into the accumulator 6 and is sucked into the compressor 2 again. After the above warm-up operation is performed for a predetermined time, the first on-off valve 17 and the second on-off valve 18 are opened, the fifth refrigerant bypass valve 65 is closed, and the heating expansion valve 21 is closed, so that the four-way valve 8 By flowing the high-temperature high-pressure gas refrigerant into the existing pipe 20, the above-described cleaning operation of the existing pipe 20 is performed.
[0041]
By performing the above warm-up operation, immediately after the start of the cleaning operation, the existing pipe 20 can be reliably cleaned and the gas-liquid separation in the accumulator 6 can be performed. In addition, when switching to the cleaning operation after the warm-up operation is completed, the four-way valve 8 is not switched, so that no energy loss occurs due to the change in the refrigerant flow direction, and energy efficiency is improved. Good cleaning operation can be performed. In the warming-up operation, the second refrigerant bypass valve 62 is closed while the heating expansion valve 21 is opened to set the flow path for allowing the outdoor heat exchanger 5 to pass. However, this setting is opposite to this setting. That is, it is good also as a flow-path setting which bypasses the outdoor heat exchanger 5 through the 2nd refrigerant | coolant bypass pipe 72 by opening the 2nd refrigerant | coolant bypass valve 62, and closing the heating expansion valve 21. FIG. In this case, the pressure control performed by the warm-up expansion valve 23 is performed by the second refrigerant bypass valve 62.
[0042]
(7) Seventh embodiment
In this embodiment, in the first to sixth embodiments, by forming a circuit in which a part of the refrigerant bypasses the oil separator 10 in the total amount, the oil separator 10 is used for the refrigerating machine oil (synthetic oil). By washing the existing pipe 20 after increasing the content of the refrigerating machine oil (synthetic oil) in the refrigerant without deliberately separating a part, the inside of the existing pipe 20 is more reliably and efficiently cleaned. It is something to try. Specifically, as shown in FIGS. 1 and 3 to 6, an oil separator 10 is connected in series to an outdoor unit pipe 77 connecting the compressor 2 and the four-way valve 8 (the oil separator 10 must be passed). In order to bypass the oil separator 10, an oil separator bypass pipe 88 connecting the suction side and discharge side piping of the oil separator 10 is provided outside the oil separator 10. The oil separator bypass three-way valve 50 is provided at the connection portion between the side pipe and the oil separator bypass pipe 88. With the above configuration, the controller 25 controls the opening and closing (port switching) of the oil separator bypass three-way valve 50, that is, the oil separator bypass three-way valve 50 is disposed on the side through which the oil separator bypass pipe 88 is passed during the cleaning operation. By switching and bypassing the oil separator 10, the refrigerant having a large amount of refrigerating machine oil is supplied to the existing pipe 20, so that the existing pipe 20 can be cleaned more reliably and efficiently. become. Note that the oil separator bypass three-way valve 50 may have any configuration such as a configuration in which the oil separator 10 is completely bypassed as a split flow type, or a configuration in which a part of the refrigerant is bypassed as a mixed type. It is not limited.
[0043]
【The invention's effect】
Since the present invention is configured as described above, the following effects can be obtained.
An air conditioner capable of cleaning existing piping during construction of the air conditioner, the outlet side of the oil separator (10) disposed on the discharge side of the compressor (2), and the suction of the compressor (2) The first refrigerant bypass pipe (71) connecting the two sides is provided, the first refrigerant bypass pipe (71) is provided with the first refrigerant bypass valve (61), and the compressor is used as a new refrigerant in the refrigerant circuit. The machine oil used is a synthetic oil such as PVE (polyvinyl ether) that is compatible with refrigerating machine oil made of mineral oil used in the compressor of the refrigerant circuit of the conventional refrigerant (CFC refrigerant) that is the object to be cleaned. The first refrigerant bypass valve (61) is opened for a predetermined time during construction of the air conditioner, and the discharged refrigerant is bypassed from the first refrigerant bypass pipe (71) to the suction side of the compressor (2). 2) Recompress some of the refrigerant after discharging The discharge pressure than a predetermined value by a large, achieving an increase in the temperature of the refrigerating machine oil consisting of synthetic oil contained in the new refrigerant, to improve the cleaning of the refrigerating machine oil for the object to be cleaned Therefore, by recompressing the refrigerant with the compressor, the refrigerant is passed through the existing piping in a higher pressure and high temperature state, and the refrigeration oil (synthetic oil) contained in the refrigerant is in a high temperature state (compatible). High state), that is, a state having high detergency, the object to be cleaned is separated from the inner wall of the pipe together with the refrigerant, so that the existing pipe can be reliably cleaned.
In addition, the existing piping can be cleaned by the newly installed air conditioner itself, not by a dedicated cleaning device that has been conventionally performed.
[0044]
In addition, the high-temperature and high-pressure refrigerant is supplied from the first refrigerant bypass pipe to the refrigerant pipe on the suction side of the compressor, and the refrigerant is kept in the existing pipe for a predetermined time while maintaining the refrigerant discharge pressure of the compressor larger than a predetermined value. Since the refrigerant that has passed through the existing pipe is circulated in the refrigerant evaporative heat supply device, the refrigerant is passed through the existing pipe at a higher pressure and temperature, and the refrigerating machine oil (synthetic oil) contained in this refrigerant By placing the object to be cleaned together with the refrigerant from the inner wall of the pipe in a high temperature state (high compatibility state), that is, a state having high detergency, the existing piping can be reliably washed.
[Brief description of the drawings]
FIG. 1 is a refrigerant circuit diagram of an engine heat pump to which the present invention is applied.
FIG. 2 is a block diagram showing a configuration of a control device and actuators.
FIG. 3 is a diagram showing a configuration of a second embodiment for cleaning existing piping.
FIG. 4 is also a diagram showing a configuration of a third embodiment.
FIG. 5 is a diagram similarly showing a configuration of a fifth embodiment.
FIG. 6 is a diagram similarly showing the configuration of the sixth embodiment.
FIG. 7 is a view showing the compatibility between refrigerating machine oil (synthetic oil) and an object to be cleaned.
FIG. 8 is a graph showing the relationship between the compatibility of refrigeration oil and the temperature.
[Explanation of symbols]
2 Compressor
4 Refrigerant evaporative heat supplier
5 Outdoor heat exchanger
6 Accumulator
8 Four-way valve
10 Oil separator
21 Expansion valve for heating
71 First refrigerant bypass pipe

Claims

An air conditioner capable of cleaning existing piping during construction of the air conditioner, the outlet side of the oil separator (10) disposed on the discharge side of the compressor (2), and the suction of the compressor (2) The first refrigerant bypass pipe (71) connecting the two sides is provided, the first refrigerant bypass pipe (71) is provided with the first refrigerant bypass valve (61), and the compressor is used as a new refrigerant in the refrigerant circuit. The machine oil is a synthetic oil that has compatibility with the refrigerating machine oil made of mineral oil used in the compressor of the refrigerant circuit of the conventional refrigerant (CFC refrigerant) that is the object to be cleaned. After the first refrigerant bypass valve (61) is opened for a predetermined time, the refrigerant discharged from the first refrigerant bypass pipe (71) is bypassed to the suction side of the compressor (2), and the compressor (2) is discharged. Recompress a part of the refrigerant to make the discharge pressure higher than the specified value. In, achieving an increase in the temperature of the refrigerating machine oil consisting of synthetic oil contained in the new refrigerant, the air conditioner, characterized in that to improve the cleaning of the refrigerating machine oil for the object to be cleaned.