JP3743343B2

JP3743343B2 - Scroll compressor

Info

Publication number: JP3743343B2
Application number: JP2001330440A
Authority: JP
Inventors: 秀信新宅; 文俊西脇; 寛長谷川; 光晴松尾
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 2001-10-29
Filing date: 2001-10-29
Publication date: 2006-02-08
Anticipated expiration: 2021-10-29
Also published as: JP2003139077A

Description

【０００１】
【発明の属する技術分野】
本発明は、業務用または家庭用、あるいは乗用車等の乗り物用の冷凍空調、あるいは冷蔵庫などに用いられる密閉型スクロール圧縮機に関するものである。
【０００２】
【従来の技術】
従来のスクロール圧縮機を図６を用いて説明する。図６のスクロール圧縮機は、密閉容器１内に圧縮機構部２、圧縮機構部２の下方に圧縮機構部２を駆動するための電動機３と、この電動機３の回転力を圧縮機構部２に伝達するための駆動軸４とを備え、密閉容器１内の下部には潤滑油溜り５が設けられている。圧縮機構部２は、渦巻きラップを有する旋回スクロール６と固定スクロール７を対向して組み合わせ、固定スクロール７と軸受けフレーム８とで旋回スクロール６の鏡板６ａを旋回運動が可能な隙間を有して挟み込んで保持された構成されている。また、電動機３はその巻線コイルのケーブルが、密閉容器１に封着された導入ターミナルに接続されて、密閉容器１の外部に引き出され、外部の電動機制御電源により駆動制御される。
【０００３】
吸入冷媒ガスは、固定スクロール７の鏡板７ａの外周から半径方向に貫通して設けた吸入管９より吸入され、固定スクロール７と旋回スクロール６とにより形成される圧縮室１０の外周に位置する吸入室１０ａより圧縮室１０ｂに流入する。旋回スクロール６は自転防止機構１１によって自転を防止され、偏心した駆動軸４により旋回軸受１２を介して旋回運動を行い、吸入冷媒ガスを順次圧縮室１０の中心方向に移送しながら圧縮し、吐出口１３よりリード弁１４を介して第１吐出室１５へ吐出する。
【０００４】
その後、圧縮され吐出された第１吐出室１５の高圧ガスは、軸受けフレーム８内の第１下降用連通路１６を通り、隔壁１７と圧縮機構部２と電動機３に囲まれた第２吐出室１８を経て、電動機３内の第２下降用連通路１９を通り下降する。さらに、電動機３外周に設けられた第１上昇用通路２０を通り電動機３を冷却した後、圧縮機構部２外周の第２上昇用通路（図示せず）を経て吐出管２１より機外へ圧送される。この間、吐出ガス中の潤滑油は遠心分離、衝突を繰り返して分離されて潤滑油溜り５に滴下する。
【０００５】
また、駆動軸４は軸受けフレーム８に固定した上主軸受２２と下主軸受２３で支持され、電動機３の駆動力により回転する。軸受けフレーム８と旋回スクロール６の間に形成された背圧室２４は、後述のように吸入圧力と吐出圧力の中間の圧力に維持されており、この背圧室２４の圧力により旋回スクロール６が固定スクロール７に押し付けられる構造となっている。
【０００６】
駆動軸４内には給油孔２５が、駆動軸４の各軸受部との摺動面には軸長手方向に微少通路２６（軸受隙間でも良い）が設けられている。上主軸受２２の電動機３側には、微少通路２６と給油孔２５を連通する貫通給油孔２８の対向する位置に潤滑油溝２９が設けられ、貫通給油孔２８から潤滑油溝２９に供給され溜まった潤滑油のシール作用により、上主軸受２２と駆動軸４の隙間から背圧室２４への高圧ガスの侵入が防止されている。
【０００７】
さらに、駆動軸４の下端は潤滑油溜り５内に浸漬されて、給油孔２５と貫通給油孔２８と微少通路２６によって背圧室２４と潤滑油溜り５は連通している。また、潤滑油溜り５は吐出圧力となっているが、微少通路２６により減圧されて、背圧室２４は吐出圧力と吸入圧力の中間の圧力である中間圧力に保たれている。したがって、潤滑油は吐出圧力のかかった潤滑油溜り５と背圧室２４との圧力差によって、給油孔２５を通じて上主軸受２２と旋回軸受１２に供給され、各軸受を潤滑したのち背圧室２４に供給される。背圧室２４に溜った潤滑油は背圧制御弁３１を介して吸入室１０ａ導かれ、そして圧縮室１０ｂへ入り、圧縮機構部２のシールと摺動部分の潤滑を行った後、吐出ガスとともに排出される。
【０００８】
尚、背圧室２４を中間圧力に保持する手段として、駆動軸４に設けた潤滑油溝と軸受けフレーム８に設けた旋回スクロール６背面の背圧仕切り帯および旋回スクロール６内に設けた減圧弁との組み合わせで、これを実現している例もある。
【０００９】
次に、図７を用いて背圧制御弁３１について説明する。図７は、背圧制御弁３１の近傍の断面図である。背圧室２４と吸入室１０ａは、背圧室２４から弁側連通孔３２と、弁となる鋼球３３を収容する調整室３４と、吸入室側連通孔３７を経由し連通している。鋼球３３は、バネ３５の弾性力により弁側連通孔３２に押さえつけられており、図７は弁側連通孔３２を鋼球３３が塞いでいる状態を示している。また、キャップ３６は、バネ３５を支持するとともに調整室３４内の潤滑油や冷媒ガスが吐出空間側へ漏れないようにシールされ固定スクロール７に固定されている。
【００１０】
図７に示す状態の鋼球３３には、下方の弁側連通孔３２より背圧室２４の圧力、上方よりバネ３５の弾性力と調整室３４の圧力（吸入室側連通孔３７を通じているため吸入室１０ａと同じ吸入圧）が作用しており、背圧室２４の圧力が上昇すると、バネ３５の弾性力に打ち勝ち鋼球３３が上方に押し込まれ、背圧室２４の潤滑油とガスが調整室３５に流れ、背圧室２４の圧力が低下し元の圧力に戻り、鋼球３３もバランス位置に戻る。このように運転時は、背圧室２４と吸入室１０ａとの圧力差がほぼ一定となるように、バネ３５により鋼球３３の開閉が制御される。
【００１１】
しかし、圧縮機が運転を停止した直後に、次のような課題が生じる。圧縮機が運転を停止すると、リード弁１４によって吐出口１３は閉じられ、吸入室１０ａは吸入圧力のままである。背圧室２４には、吐出圧力のかかった潤滑油溜り５から給油孔２５と貫通給油孔２８と微少通路２６を通じ潤滑油が流入する。そして、背圧室２４の圧力が上昇するため背圧制御弁３１が開き、背圧室２４の潤滑油は背圧制御弁３１と吸入室１０ａを経由して吸入側へ逆流して流出し、潤滑油溜り５の潤滑油が急激に減少することになる。
【００１２】
リード弁１４を設けていない場合は、潤滑油溜り５の潤滑油の吸入側への逆流は発生しないが、吐出圧力と吸入圧力の差圧によって旋回スクロール６が逆転を起こす事が知られている。特開昭５７−７３８８６号に開示されているように、旋回スクロール６を逆転させないために、一般的にリード弁１４が取り付けられていることが多い。一方、特公平１−３４３１２号に開示されているように、吸入管９内部にバネと開閉弁を用いた吸入逆止弁を取り付け、旋回スクロール６の逆転防止と潤滑油の逆流を防止した実施例もある。
【００１３】
【発明が解決しようとする課題】
しかしながら上記従来のリード弁を用いた構成によれば、運転停止時の旋回スクロールの逆転は防止できるものの潤滑油の逆流は発生してしまい、潤滑油溜りの潤滑油減少による給油量不足が生じ、軸受けなどの摺動部で焼き付きや、摩耗が発生するという課題がある。
【００１４】
リード弁を用いない場合は、潤滑油の逆流は防止できるものの旋回スクロールの逆転が起こり、逆転音が発生してしまう等の課題がある上、さらに運転時の効率向上を考慮すると、旋回スクロールと固定スクロールのラップの巻き数を増加させ高圧縮比とする必要があり、圧縮機が大型化するといった課題もある。
【００１５】
一方、吸入逆止弁を取り付けて運転停止時の潤滑油の逆流を防止した場合、バネや開閉弁といった部品点数の増加や、吸入管等の加工精度の向上、組立生産性の悪化、また、図６の従来例のように吸入管が横から挿入されている場合にはスペースの制約から吸入弁が設置できないという課題を有していた。
【００１６】
本発明はこのような従来の課題を解決するものであり、運転停止時に旋回スクロールが逆転することなく、かつ潤滑油溜りの潤滑油が吸入側へ逆流するのを防止することができ、しかも簡易構造にして加工性および組立生産性の良い密閉型スクロール圧縮機を提供することを目的とする。
【００１７】
【課題を解決するための手段】
上記課題を解決するために本発明は、密閉容器内に、固定スクロールと旋回スクロールからなる圧縮機構部と、前記圧縮機構部を駆動する駆動軸と、前記駆動軸を支持する主軸受けを設けた軸受けフレームと、前記駆動軸を回転駆動する電動機が設けられ、
前記旋回スクロールの背面と前記軸受けフレームにて形成される背圧空間と前記圧縮機構部の吸入室とを連通する背圧連通孔と、前記背圧連通孔を開閉し前記背圧室の圧力を吸入圧力と吐出圧力の中間の圧力とする背圧制御手段を有し、
潤滑油溜りの潤滑油を、前記密閉容器内の吐出圧と前記背圧室の圧力差により前記駆動軸内に設けた給油孔と前記主軸受け摺動部を経由し前記背圧室へ供給し、さらに前記背圧室と吸入室の圧力差により前記背圧連通孔を経由し前記圧縮機構部に供給する給油機構とを備えたスクロール圧縮機において、
前記電動機の運転時には前記背圧連通孔を開け、停止時には閉じる背圧連通孔開閉手段を設けたことを特徴とするスクロール圧縮機である。
【００１８】
また、本発明は、前記背圧連通孔開閉手段が、前記背圧連通孔を開閉する弁体と、前記弁体を開閉駆動する弁体駆動部を有することを特徴とするスクロール圧縮機ものである。
【００１９】
また、前記背圧連通孔開閉手段が、前記背圧制御手段と一体に構成され、前記連通孔を開閉する前期背圧制御手段の開閉弁を兼ねる前期弁体と、前記背圧連通孔が閉じる側に前記弁体を押し付ける押し部材と、前記電動機の停止時のみ前記押し部材を介して前記弁体を押し付け前記背圧連通孔を閉じる弁体駆動部を有することを特徴とするスクロール圧縮機である。
【００２０】
また、本発明は、前記弁体駆動部が電磁コイルを有し、前記電磁コイルが前記電動機のコイルと直列または並列に結線されたことを特徴とするスクロール圧縮機である。
【００２１】
また、本発明は、前記電磁コイルと前記電動機のコイルが、前記密閉容器内で結線されたことを特徴とするスクロール圧縮機である。
【００２２】
【発明の実施の形態】
本発明の実施の形態におけるスクロール圧縮機の構成において、従来例として説明した図６と同一機能部品については同一番号を使用し、同一の構成および作用の説明は省くことにする。
【００２３】
尚、本発明の実施の形態におけるスクロール圧縮機は、ＨＦＣ４１０Ａを冷媒に用いた場合を例に説明するが、ＨＦＣ１３４ａ、ハイドロカーボン（ＨＣ）等の塩素を含まない冷媒や、二酸化炭素、従来のＨＣＦＣ２２などの冷媒を用いた場合にも同様に適用可能であり、同様の効果を得ることができる。
【００２４】
（実施の形態例１）
本発明の実施の形態１について、図１及び図２を用いて説明する。図１、図２は、本発明の実施の形態１におけるスクロール圧縮機の圧縮機構部主要部の縦断面図であり、図１は運転動作時、図２は運転停止時の状態を示したものである。
【００２５】
図１において、４１は背圧連通孔開閉弁で、吸入側連通孔３７を開閉できるように設置されている。また、３１は背圧制御弁で、図６の従来例と同様のものである。
【００２６】
背圧連通孔開閉弁４１は、吸入側連通孔３７と交差する弁ガイド孔４２と、弁ガイド孔４２内を移動可能に設置されその移動により交差する吸入側連通孔３７を開閉する棒状の弁体４３と、電磁力を弁体４３に作用させる電磁コイル４４と、弁体４３に吸入側連通孔３７を閉じる方向の弾性力を作用させるバネ４５と、弁体４３とバネ４５及び電磁コイル４４を支持し固定スクロール７に設置固定するホルダー４６とで構成されている。また、ホルダー４６の内側上部には鉄片４６ａが設置されており、電磁コイル４４が発生する磁界により鉄片４６ａが磁化され、弁体４３との間に電磁力による吸引力が作用し、弁体４３が上方に引き上げられる。ここでの電磁コイル４４は、制御電源４７に接続され、その通電を制御されている。また電磁コイル４４への通電は、電動機３の通電スイッチと連動して行なわれている。
【００２７】
図１は、スクロール圧縮機が運転されている時の状態で、制御電源４７により電磁コイル４４に通電され、弁体４３が電磁力の作用で図の上方に引き上げられ、吸入側連通孔３７が開いている状態を示している。
【００２８】
図２は、スクロール圧縮機の運転が停止された時の状態で、制御電源４７により電磁コイル４４の通電が切られ、弁体４３がバネ４５の弾性力の作用により図の下方に押し下げられ、弁体４３で吸入側連通孔３７が閉じられている状態を示している。
【００２９】
本実施例では、弁体４３と弁ガイド孔４２の形状は、加工性と組立性を考慮し円筒形状としその断面直径は吸入側連通孔（φ１）を十分閉じることができる大きさφ２とし、弁ガイド孔４２と弁体４３の隙間は、冷媒ガスや潤滑油の漏れがないように（ここでは約１０μｍ）設定した。弁体４３には、電磁力の作用を考慮しＳ４５Ｃ材を用いた。弾性体のバネ４５にはコイルバネを用いた。尚、冷媒ガス、潤滑油、使用条件などにより、これらの仕様も異なることは言うまでもない。
【００３０】
次に、本実施例の動作を説明する。運転中は、電磁コイル４４に通電されると発生する電磁力により、図１のように弁体４３は上方に引き上げられ吸入側連通孔３７は開けられるため、図６の従来例と同じく背圧制御弁３１は機能する。
【００３１】
運転が停止すると、電磁コイル４４の通電が切れ電磁力が作用せず、図２のように弁体４３がバネ４５の弾性力の作用により図の下方に押し下げられ、弁体４３で吸入側連通孔３７が閉じられる。そのため、背圧室２４と吸入室１０ａの圧力差により背圧制御弁３１が開いても、背圧室２４から吸入室１０ａへの潤滑油やガスは流れない。従って、潤滑油溜り５の潤滑油が背圧制御弁３１と吸入室１０ａを経由して吸入側へ逆流することを防止でき、潤滑油溜り５の潤滑油が急激な減少を防止できる。
【００３２】
このように、上記実施の形態１の構成によれば、簡単な構成で確実に、運転停止時に弁体４３で吸入側連通孔３７を閉じることができるため、潤滑油溜り５から吸入側への潤滑油の逆流を防止することが可能となり、安価に、スクロール圧縮機の信頼性を向上することができる。
【００３３】
尚、弁体４３をＳ４５Ｃ材で構成したが、これに限るものはなく、さらにその断面形状は円に限らず、楕円、四角形でも、同様の効果が得られることは言うまでもない。また、弁体４３の弁ガイド孔４２に挿入される部分をアルミ材などの非磁性材や低透磁率の材料とし、電磁コイル４４の電磁力が作用する部分を磁性体や高透磁率の材料で構成しても、上記実施例と同様の動作を実現でき、同様の効果が得られることは言うまでもない。
【００３４】
（実施の形態例２）
次に、本発明の実施の形態２について、図３と図４を用いて説明する。図３、図４は、本発明の実施の形態２におけるスクロール圧縮機の圧縮機構部主要部の縦断面図であり、図３は運転動作時、図４は運転停止時の状態を示したものである。
【００３５】
実施の形態１との違いは、背圧連通孔開閉弁と背圧制御弁とが一体に構成され、ここでは、背圧制御弁の鋼球３３が両方の弁の役目をしている点である。
【００３６】
図３において、５１は背圧連通孔開閉弁で、調整室３４内の鋼球３３を下方に押し付ける棒状の押し部材５３と、押し部材５３が挿入されその移動方向を規制する弁ガイド孔５２と、押し部材５３を上方に引き上げる電磁力を作用さる電磁コイル５４と、押し部材５３を下方に押し下げ鋼球３３を弁側連通孔３２に押し付ける弾性力を作用させるバネ５５と、押し部材５３とバネ５５及び電磁コイル５５を内包支持し固定スクロール７に設置固定するホルダーキャップ５６で構成されている。また、ホルダーキャップ５６は、背圧制御弁３１のバネ３５を支持するとともに、調整室３４内の潤滑油や冷媒ガスが吐出空間側へ漏れないようにシールされ固定スクロール７に固定されている。ここでも実施の形態１と同様に、電磁コイル４４への通電は、電動機３の通電スイッチと連動して行なわれている。
【００３７】
次に、本実施例の動作を説明する。図１のように運転中は、背圧連通孔開閉弁５１の電磁コイル５４が通電され発生する電磁力により、押し部材５３が上方に引き上げられるため、押し部材５３は背圧制御弁３１の鋼球３３には接触しない。そのため従来と同様に、背圧制御弁３１は、背圧室２４の圧力と吸入室１０ａの圧力及びバネ３５の弾性力により弁側連通孔３２を開閉し、背圧室２４と吸入室１０ａの差圧がほぼ一定となるよう制御することができる。
【００３８】
運転が停止すると、コイル５４の通電が切れるため、図４のように押し部材５３がバネ５５の弾性力の作用により図の下方に押し下げられ、鋼球３３で弁側連通孔３２を閉じる。背圧室２４と吸入室１０ａの圧力差により鋼球３３が上方に力を受けても鋼球３３は上方にあがらず弁側連通孔３２を閉じたままにできるため、背圧室２４から吸入室１０ａへ潤滑油や冷媒ガスが流入することがない。従って、潤滑油溜り５の潤滑油が背圧制御弁３１と吸入室１０ａを経由して吸入側へ逆流することを防止でき、潤滑油溜り５の潤滑油が急激な減少も防止できる。
【００３９】
このように、上記実施の形態２の構成によれば、運転停止時に押し部材５３を介し鋼球３３で弁側連通孔３２を閉じることが可能となり、実施の形態１より簡単な構成で確実に、潤滑油溜り５から吸入側への潤滑油の逆流を防止することができ、安価に、スクロール圧縮機の信頼性の向上を実現することができる。
【００４０】
また、背圧連通孔開閉弁４１と背圧制御弁３１を一体化した構成にすることで、実施の形態１よりも部品点数や加工箇所を減らせるため、より加工性および組立生産性が向上できるとともにコスト低減も実現できる。
【００４１】
（実施の形態例３）
次に、本発明の実施の形態３について、図５を用いて説明する。図５は、電動機と背圧連通孔開閉弁及び制御電源との結線を示した図である。
【００４２】
本発明の実施の形態３と実施の形態１、２との違いは、背圧連通孔開閉弁６１の電磁コイル６２が、電動機３のコイルの巻線６４の一本と直列に、コンプレッサの密閉容器１の内部で接続されている点である。尚、背圧連通孔開閉弁６１の構成及び動作は、実施の形態１、２の背圧連通制御弁４１、５１と同様である。
【００４３】
実施の形態１、２においては、各々の背圧連通孔開閉弁４１、５１は、その電磁コイル４４，５４が、各々の制御電源４７と接続され、電動機３の通電スイッチと一緒に、その通電を制御されている。これらの構成では、電動機３の制御電源とは別に制御電源４７を設け、密閉容器１から電磁コイル４４，５４のケーブルを引き出す導入ターミナル３０も別に設けていた。
【００４４】
本実施例では、図５に示すように、背圧連通孔開閉弁６１の電磁コイル６２が、電動機３のコイル巻線６４の一本と直列に、コンプレッサの密閉容器１の内部で接続されている。スクロール圧縮機の運転時は電動機３に制御電源６７から通電されると、背圧連通孔開閉弁６１の電磁コイル６２にも通電され、背圧連通孔開閉弁６１が開かれる。また、スクロール圧縮機の運転が停止されると、制御電源６７からの通電が切られるため、電動機３の停止と共に、背圧連通孔開閉弁６１が閉じられる。
【００４５】
この上記実施の形態３の構成によれば、第１、第２の実施例同様に停止時の潤滑油の逆流を防止できるとともに、電動機３の制御電源６７で電磁コイル６２の制御電源を兼ね共用でき、導入ターミナル６５も別に設ける必要なく、実施の形態１及び２より簡単で安価な構成で、スクロール圧縮機の信頼性の向上を実現することができる。
【００４６】
尚、上記実施の形態３においては、電磁コイル６２をコイル巻線６４に直列に接続した例を示したが、例えば図５のコイル巻線６４のＵ，Ｖ線間に並列に接続した構成にしても同様の効果が得られる。また、Ｕ，Ｖ，Ｗ線からの誘起電圧で通電する構成にしても、上記と同様の効果が得られる。
【００４７】
尚、コイル巻線６４のＵ，Ｖ、Ｗ線の結線方法も、他の結線方法でもよい。さらに、電動機もＵ，Ｖ，Ｗの３相で駆動されるものに限るものではなく、２相または多相で駆動される電動機や、直流電動機であっても、上記と同様の効果が得られる。
【００４８】
尚、上記実施の形態１〜３においては、背圧連通孔開閉弁の駆動手段として電磁コイルを用いたが、例えば電動機、流体機械など、他の駆動手段を用いてもよく、上記実施の形態１〜３と同様の効果が得られる。
【００４９】
尚、上記実施の形態１〜３においては、背圧連通孔開閉弁の弁の復元力としてバネによる弾性力を用いたが、例えば磁力や、冷媒ガスや潤滑油などの流体から受ける力、または重力など、他の復元力を用いてもよく、上記実施の形態１〜３と同様の効果が得られる。
【００５０】
【発明の効果】
本発明は、圧縮機の停止時に背圧連通孔を閉じるため、潤滑油溜りの潤滑油が吸入側へ逆流するのを抑制し、潤滑油の減少を防止することができ、簡易構造にして組立生産性がよく、信頼性の高い密閉型スクロール圧縮機を提供することができる。
【００５１】
また、背圧制御弁と背圧連通孔開閉手段を一体に構成することにより、コンパクトで設置スペースが少なくでき、設計の自由度が保て、部品点数も少なくてすむためより安価にでき、簡易構造で組立生産性を良くすることができる。
【００５２】
また、密閉容器内で、背圧連通孔開閉手段の電磁コイルと電動機のコイルと直列または並列に結線することにより、より簡単な構成でコンパクトにでき、設計の自由度が保て、部品点数も少なくてすむためより安価にでき、簡易構造で組立生産性を良くすることができる。
【図面の簡単な説明】
【図１】本発明の実施の形態１におけるスクロール圧縮機の運転動作時の主要部を拡大した縦断面図
【図２】本発明の実施の形態１におけるスクロール圧縮機の運転停止時の主要部を拡大した縦断面図
【図３】本発明の実施の形態２におけるスクロール圧縮機の運転動作時の主要部を拡大した縦断面図
【図４】本発明の実施の形態２におけるスクロール圧縮機の運転停止時の主要部を拡大した縦断面図
【図５】本発明の実施の形態３における接続説明の図
【図６】従来のスクロール圧縮機の縦断面図
【図７】従来のスクロール圧縮機の主要部を拡大した縦断面図
【符号の説明】
１密閉容器
２圧縮機構
３,６３電動機
４駆動軸
５潤滑油溜り
６旋回スクロール
７固定スクロール
８軸受けフレーム
２４背圧室
２５給油孔
３０，６５導入ターミナル
３１背圧調整弁
３２弁側連通孔
３３鋼球
３４調整室
３５バネ
３６キャップ
３７吸入側連通孔
４１，５１，６１背圧連通孔開閉弁
４２，５２弁ガイド孔
４３弁体
４４，５４電磁コイル
４５，５５バネ
４６ホルダー
４７，６７制御電源
５３押し部材
６４コイル巻線
６５導入ターミナル[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a hermetic scroll compressor for use in a refrigeration air conditioner for a vehicle for business use, home use, or a vehicle such as a passenger car, or a refrigerator.
[0002]
[Prior art]
A conventional scroll compressor will be described with reference to FIG. The scroll compressor of FIG. 6 includes a compression mechanism unit 2 in the hermetic container 1, an electric motor 3 for driving the compression mechanism unit 2 below the compression mechanism unit 2, and the rotational force of the electric motor 3 to the compression mechanism unit 2. A drive shaft 4 for transmission is provided, and a lubricating oil reservoir 5 is provided in the lower part of the sealed container 1. The compression mechanism unit 2 combines the orbiting scroll 6 having a spiral wrap and the fixed scroll 7 so as to face each other, and the fixed scroll 7 and the bearing frame 8 sandwich the end plate 6a of the orbiting scroll 6 with a gap capable of orbiting motion. Is held in. The electric motor 3 is connected to an introduction terminal sealed in the hermetic container 1 with the cable of the winding coil, drawn out of the hermetic container 1, and driven and controlled by an external motor control power source.
[0003]
The suction refrigerant gas is sucked in from a suction pipe 9 provided in a radial direction from the outer periphery of the end plate 7 a of the fixed scroll 7, and is sucked in the outer periphery of the compression chamber 10 formed by the fixed scroll 7 and the orbiting scroll 6. It flows into the compression chamber 10b from the chamber 10a. The orbiting scroll 6 is prevented from rotating by an anti-rotation mechanism 11, performs an orbiting motion via an orbiting bearing 12 by an eccentric drive shaft 4, compresses the sucked refrigerant gas while sequentially transporting it toward the center of the compression chamber 10, and discharges it. Discharge from the outlet 13 to the first discharge chamber 15 via the reed valve 14.
[0004]
Thereafter, the compressed and discharged high-pressure gas in the first discharge chamber 15 passes through the first lowering communication passage 16 in the bearing frame 8, and is surrounded by the partition wall 17, the compression mechanism portion 2, and the electric motor 3. After passing through 18, the electric vehicle 3 descends through the second descending communication passage 19. Further, after cooling the electric motor 3 through the first ascending passage 20 provided on the outer periphery of the electric motor 3, it is pumped from the discharge pipe 21 to the outside of the apparatus via the second ascending passage (not shown) on the outer periphery of the compression mechanism section 2. Is done. During this time, the lubricating oil in the discharged gas is separated by repeated centrifugal separation and collision and dropped into the lubricating oil reservoir 5.
[0005]
The drive shaft 4 is supported by an upper main bearing 22 and a lower main bearing 23 fixed to the bearing frame 8, and is rotated by the driving force of the electric motor 3. The back pressure chamber 24 formed between the bearing frame 8 and the orbiting scroll 6 is maintained at an intermediate pressure between the suction pressure and the discharge pressure, as will be described later. It is structured to be pressed against the fixed scroll 7.
[0006]
An oil supply hole 25 is provided in the drive shaft 4, and a minute passage 26 (may be a bearing gap) is provided in a longitudinal direction of the shaft on a sliding surface with each bearing portion of the drive shaft 4. On the motor 3 side of the upper main bearing 22, a lubricating oil groove 29 is provided at a position opposed to a through oil supply hole 28 that communicates the minute passage 26 and the oil supply hole 25, and is supplied from the through oil supply hole 28 to the lubricating oil groove 29. The sealing action of the accumulated lubricating oil prevents high-pressure gas from entering the back pressure chamber 24 through the gap between the upper main bearing 22 and the drive shaft 4.
[0007]
Further, the lower end of the drive shaft 4 is immersed in the lubricating oil reservoir 5, and the back pressure chamber 24 and the lubricating oil reservoir 5 communicate with each other through the oil supply hole 25, the through oil supply hole 28 and the minute passage 26. Further, although the lubricating oil reservoir 5 is at the discharge pressure, the pressure is reduced by the minute passage 26, and the back pressure chamber 24 is maintained at an intermediate pressure which is an intermediate pressure between the discharge pressure and the suction pressure. Accordingly, the lubricating oil is supplied to the upper main bearing 22 and the orbiting bearing 12 through the oil supply hole 25 due to a pressure difference between the lubricating oil reservoir 5 to which the discharge pressure is applied and the back pressure chamber 24, and after lubricating each bearing, the back pressure chamber is supplied. 24. Lubricating oil accumulated in the back pressure chamber 24 is guided to the suction chamber 10a through the back pressure control valve 31, and enters the compression chamber 10b to lubricate the seal and the sliding portion of the compression mechanism 2 and then discharge gas. It is discharged with.
[0008]
Incidentally, as means for maintaining the back pressure chamber 24 at an intermediate pressure, a lubricating oil groove provided on the drive shaft 4 and a back pressure partition band on the back of the orbiting scroll 6 provided on the bearing frame 8 and a pressure reducing valve provided in the orbiting scroll 6 are provided. There is an example which realizes this in combination with.
[0009]
Next, the back pressure control valve 31 will be described with reference to FIG. FIG. 7 is a cross-sectional view of the vicinity of the back pressure control valve 31. The back pressure chamber 24 and the suction chamber 10 a communicate from the back pressure chamber 24 via a valve side communication hole 32, an adjustment chamber 34 that houses a steel ball 33 that serves as a valve, and a suction chamber side communication hole 37. The steel ball 33 is pressed against the valve side communication hole 32 by the elastic force of the spring 35, and FIG. 7 shows a state where the steel ball 33 closes the valve side communication hole 32. The cap 36 supports the spring 35 and is sealed and fixed to the fixed scroll 7 so that the lubricating oil and refrigerant gas in the adjustment chamber 34 do not leak to the discharge space side.
[0010]
The steel ball 33 in the state shown in FIG. 7 has a pressure in the back pressure chamber 24 from the lower valve side communication hole 32, an elastic force of the spring 35 and a pressure in the adjustment chamber 34 from the upper side (because the suction chamber side communication hole 37 is passed through When the pressure in the back pressure chamber 24 rises and the pressure in the back pressure chamber 24 rises, the elastic force of the spring 35 is overcome and the steel ball 33 is pushed upward, so that the lubricating oil and gas in the back pressure chamber 24 are It flows into the adjustment chamber 35, the pressure in the back pressure chamber 24 decreases and returns to the original pressure, and the steel ball 33 also returns to the balance position. Thus, during operation, the opening and closing of the steel ball 33 is controlled by the spring 35 so that the pressure difference between the back pressure chamber 24 and the suction chamber 10a becomes substantially constant.
[0011]
However, immediately after the compressor stops operating, the following problems arise. When the compressor stops operating, the discharge port 13 is closed by the reed valve 14, and the suction chamber 10a remains at the suction pressure. Lubricating oil flows into the back pressure chamber 24 from the lubricating oil reservoir 5 to which discharge pressure is applied through the oil supply hole 25, the through oil supply hole 28, and the minute passage 26. Then, since the pressure in the back pressure chamber 24 increases, the back pressure control valve 31 opens, and the lubricating oil in the back pressure chamber 24 flows back to the suction side through the back pressure control valve 31 and the suction chamber 10a and flows out. Lubricating oil in the lubricating oil reservoir 5 is rapidly reduced.
[0012]
In the case where the reed valve 14 is not provided, the backflow of the lubricating oil reservoir 5 to the suction side of the lubricating oil does not occur, but it is known that the orbiting scroll 6 reverses due to the differential pressure between the discharge pressure and the suction pressure. . As disclosed in JP-A-57-73886, a reed valve 14 is generally attached in order to prevent the orbiting scroll 6 from being reversed. On the other hand, as disclosed in Japanese Examined Patent Publication No. 1-334312, an intake check valve using a spring and an on-off valve is attached inside the intake pipe 9 to prevent reverse rotation of the orbiting scroll 6 and backflow of lubricating oil. There are also examples.
[0013]
[Problems to be solved by the invention]
However, according to the configuration using the above-described conventional reed valve, although the reverse rotation of the orbiting scroll at the time of operation stop can be prevented, the backflow of the lubricating oil occurs, resulting in an insufficient amount of oil supply due to a decrease in the lubricating oil in the lubricating oil pool, There is a problem that seizure or wear occurs in a sliding portion such as a bearing.
[0014]
When the reed valve is not used, the reverse flow of the lubricating oil can be prevented, but there are problems such as the reverse rotation of the orbiting scroll and the occurrence of reverse rotation noise. It is necessary to increase the number of windings of the fixed scroll wrap to obtain a high compression ratio, and there is a problem that the compressor is increased in size.
[0015]
On the other hand, if a check valve is installed to prevent backflow of lubricating oil when operation is stopped, the number of parts such as springs and on / off valves will increase, the processing accuracy of suction pipes will improve, assembly productivity will deteriorate, When the suction pipe is inserted from the side as in the conventional example of FIG. 6, there is a problem that the suction valve cannot be installed due to space limitations.
[0016]
The present invention solves such a conventional problem and can prevent the turning scroll from reversing when the operation is stopped and prevent the lubricating oil in the lubricating oil pool from flowing backward to the suction side. An object of the present invention is to provide a hermetic scroll compressor having a structure and good workability and assembly productivity.
[0017]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention is provided with a compression mechanism portion composed of a fixed scroll and a turning scroll, a drive shaft for driving the compression mechanism portion, and a main bearing for supporting the drive shaft in a sealed container. A bearing frame and an electric motor for rotationally driving the drive shaft;
A back pressure communication hole communicating the back pressure space formed by the back surface of the orbiting scroll and the bearing frame and the suction chamber of the compression mechanism, and opening and closing the back pressure communication hole to reduce the pressure of the back pressure chamber. It has back pressure control means that makes the pressure intermediate between the suction pressure and the discharge pressure,
Lubricating oil in the lubricating oil reservoir is supplied to the back pressure chamber via an oil supply hole provided in the drive shaft and the main bearing sliding portion due to a pressure difference between the discharge pressure in the sealed container and the back pressure chamber. Further, in the scroll compressor further comprising an oil supply mechanism that supplies the compression mechanism portion via the back pressure communication hole due to a pressure difference between the back pressure chamber and the suction chamber.
The scroll compressor is provided with a back pressure communication hole opening / closing means that opens the back pressure communication hole during operation of the electric motor and closes it when the motor stops.
[0018]
Further, the present invention provides the scroll compressor, wherein the back pressure communication hole opening / closing means includes a valve body that opens and closes the back pressure communication hole, and a valve body drive unit that drives the valve body to open and close. is there.
[0019]
The back pressure communication hole opening / closing means is configured integrally with the back pressure control means, and the previous pressure valve body serving also as the opening / closing valve of the previous pressure control means for opening / closing the communication hole, and the back pressure communication hole are closed. A scroll compressor, comprising: a pressing member that presses the valve body to a side; and a valve body driving unit that presses the valve body through the pressing member only when the electric motor is stopped and closes the back pressure communication hole. is there.
[0020]
Further, the present invention is the scroll compressor, wherein the valve body driving unit has an electromagnetic coil, and the electromagnetic coil is connected in series or in parallel with the coil of the electric motor.
[0021]
The present invention is the scroll compressor, wherein the electromagnetic coil and the coil of the electric motor are connected in the sealed container.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
In the configuration of the scroll compressor according to the embodiment of the present invention, the same reference numerals are used for the same functional parts as in FIG. 6 described as the conventional example, and the description of the same configuration and operation is omitted.
[0023]
The scroll compressor according to the embodiment of the present invention will be described using an example in which HFC410A is used as a refrigerant. However, a refrigerant not containing chlorine such as HFC134a and hydrocarbon (HC), carbon dioxide, and conventional HCFC22. Similarly, when a refrigerant such as is used, the same effect can be obtained.
[0024]
(Embodiment 1)
Embodiment 1 of the present invention will be described with reference to FIGS. 1 and 2 are longitudinal sectional views of the main part of the compression mechanism of the scroll compressor according to Embodiment 1 of the present invention. FIG. 1 shows a state during operation, and FIG. 2 shows a state when operation is stopped. It is.
[0025]
In FIG. 1, reference numeral 41 denotes a back pressure communication hole opening / closing valve, which is installed so as to open and close the suction side communication hole 37. Reference numeral 31 denotes a back pressure control valve which is the same as the conventional example of FIG.
[0026]
The back pressure communication hole opening / closing valve 41 is a rod-shaped valve that opens and closes the valve guide hole 42 that intersects the suction side communication hole 37 and the suction side communication hole 37 that is installed so as to be movable in the valve guide hole 42. Body 43, electromagnetic coil 44 for applying electromagnetic force to valve body 43, spring 45 for applying elastic force in the direction of closing suction side communication hole 37 to valve body 43, valve body 43, spring 45 and electromagnetic coil 44. And a holder 46 that is installed and fixed to the fixed scroll 7. Further, an iron piece 46 a is installed on the inner upper portion of the holder 46, the iron piece 46 a is magnetized by the magnetic field generated by the electromagnetic coil 44, and an attractive force due to electromagnetic force acts between the valve element 43 and the valve element 43. Is raised upward. Here, the electromagnetic coil 44 is connected to a control power supply 47 and its energization is controlled. Further, energization of the electromagnetic coil 44 is performed in conjunction with the energization switch of the electric motor 3.
[0027]
FIG. 1 shows a state in which the scroll compressor is in operation. The control power supply 47 energizes the electromagnetic coil 44, the valve element 43 is pulled upward by the action of electromagnetic force, and the suction side communication hole 37 is formed. Shows open state.
[0028]
FIG. 2 shows a state in which the operation of the scroll compressor is stopped, the energization of the electromagnetic coil 44 is turned off by the control power supply 47, and the valve body 43 is pushed downward by the action of the elastic force of the spring 45. A state in which the suction side communication hole 37 is closed by the valve body 43 is shown.
[0029]
In the present embodiment, the shape of the valve body 43 and the valve guide hole 42 is a cylindrical shape in consideration of processability and assemblability, and the cross-sectional diameter thereof is a size φ2 that can sufficiently close the suction side communication hole (φ1). The gap between the valve guide hole 42 and the valve body 43 was set so that refrigerant gas and lubricating oil did not leak (here, about 10 μm). S45C material was used for the valve body 43 in consideration of the action of electromagnetic force. A coil spring was used as the elastic spring 45. Needless to say, these specifications differ depending on the refrigerant gas, lubricating oil, use conditions, and the like.
[0030]
Next, the operation of this embodiment will be described. During operation, because the electromagnetic force generated when the electromagnetic coil 44 is energized, the valve body 43 is pulled upward and the suction side communication hole 37 is opened as shown in FIG. The control valve 31 functions.
[0031]
When the operation is stopped, the energization of the electromagnetic coil 44 is cut off and the electromagnetic force does not act, and the valve body 43 is pushed downward by the action of the elastic force of the spring 45 as shown in FIG. The hole 37 is closed. Therefore, even if the back pressure control valve 31 is opened due to a pressure difference between the back pressure chamber 24 and the suction chamber 10a, lubricating oil and gas from the back pressure chamber 24 to the suction chamber 10a do not flow. Therefore, the lubricating oil in the lubricating oil reservoir 5 can be prevented from flowing back to the suction side via the back pressure control valve 31 and the suction chamber 10a, and the lubricating oil in the lubricating oil reservoir 5 can be prevented from rapidly decreasing.
[0032]
As described above, according to the configuration of the first embodiment, the suction side communication hole 37 can be closed with the valve body 43 when the operation is stopped reliably with a simple configuration. It becomes possible to prevent the backflow of the lubricating oil, and the reliability of the scroll compressor can be improved at a low cost.
[0033]
In addition, although the valve body 43 was comprised with S45C material, it is not restricted to this, Furthermore, it cannot be overemphasized that the same effect is acquired even if the cross-sectional shape is not restricted to a circle | round | yen but an ellipse and a square. Further, a portion inserted into the valve guide hole 42 of the valve body 43 is made of a non-magnetic material such as an aluminum material or a low magnetic permeability material, and a portion where the electromagnetic force of the electromagnetic coil 44 acts is made of a magnetic material or a high magnetic permeability material. Of course, the same operation as in the above embodiment can be realized and the same effect can be obtained.
[0034]
(Embodiment 2)
Next, a second embodiment of the present invention will be described with reference to FIGS. 3 and 4 are longitudinal sectional views of the main part of the compression mechanism of the scroll compressor according to Embodiment 2 of the present invention. FIG. 3 shows a state during operation, and FIG. 4 shows a state when operation is stopped. It is.
[0035]
The difference from the first embodiment is that the back pressure communication hole opening / closing valve and the back pressure control valve are integrally formed, and here, the steel ball 33 of the back pressure control valve serves as both valves. is there.
[0036]
In FIG. 3, reference numeral 51 denotes a back pressure communication hole opening / closing valve, a rod-shaped pressing member 53 that presses the steel ball 33 in the adjustment chamber 34 downward, and a valve guide hole 52 into which the pressing member 53 is inserted and restricts its moving direction. , An electromagnetic coil 54 that exerts an electromagnetic force that pulls the push member 53 upward, a spring 55 that pushes the push member 53 downward and pushes the steel ball 33 against the valve-side communication hole 32, and a push member 53 and a spring And a holder cap 56 that supports the inner coil 55 and the electromagnetic coil 55 and is fixed to the fixed scroll 7. The holder cap 56 supports the spring 35 of the back pressure control valve 31 and is sealed and fixed to the fixed scroll 7 so that the lubricating oil and the refrigerant gas in the adjustment chamber 34 do not leak to the discharge space side. Here, similarly to the first embodiment, the energization of the electromagnetic coil 44 is performed in conjunction with the energization switch of the electric motor 3.
[0037]
Next, the operation of this embodiment will be described. During operation as shown in FIG. 1, the pushing member 53 is pulled upward by the electromagnetic force generated when the electromagnetic coil 54 of the back pressure communication hole opening / closing valve 51 is energized. It does not touch the sphere 33. Therefore, as in the conventional case, the back pressure control valve 31 opens and closes the valve side communication hole 32 by the pressure of the back pressure chamber 24, the pressure of the suction chamber 10a, and the elastic force of the spring 35, and the back pressure chamber 24 and the suction chamber 10a. The differential pressure can be controlled to be substantially constant.
[0038]
When the operation is stopped, the coil 54 is de-energized. Therefore, as shown in FIG. 4, the pushing member 53 is pushed downward by the action of the elastic force of the spring 55, and the valve-side communication hole 32 is closed by the steel ball 33. Even if the steel ball 33 receives a force upward due to the pressure difference between the back pressure chamber 24 and the suction chamber 10a, the steel ball 33 does not rise upward and the valve side communication hole 32 can be kept closed. Lubricating oil or refrigerant gas does not flow into the chamber 10a. Therefore, it is possible to prevent the lubricating oil in the lubricating oil reservoir 5 from flowing back to the suction side via the back pressure control valve 31 and the suction chamber 10a, and it is possible to prevent the lubricating oil in the lubricating oil reservoir 5 from rapidly decreasing.
[0039]
As described above, according to the configuration of the second embodiment, the valve side communication hole 32 can be closed with the steel ball 33 via the push member 53 when the operation is stopped. The backflow of the lubricating oil from the lubricating oil reservoir 5 to the suction side can be prevented, and the reliability of the scroll compressor can be improved at a low cost.
[0040]
In addition, since the back pressure communication hole opening / closing valve 41 and the back pressure control valve 31 are integrated, the number of parts and the processing points can be reduced as compared with the first embodiment, so that workability and assembly productivity are further improved. As well as cost reduction.
[0041]
(Embodiment 3)
Next, Embodiment 3 of the present invention will be described with reference to FIG. FIG. 5 is a diagram showing connections between the electric motor, the back pressure communication hole opening / closing valve, and the control power source.
[0042]
The difference between the third embodiment of the present invention and the first and second embodiments is that the electromagnetic coil 62 of the back pressure communication hole opening / closing valve 61 is sealed in series with one of the coil windings 64 of the motor 3. It is a point connected inside the container 1. The configuration and operation of the back pressure communication hole opening / closing valve 61 are the same as those of the back pressure communication control valves 41 and 51 of the first and second embodiments.
[0043]
In the first and second embodiments, each back pressure communication opening / closing valve 41, 51 has its electromagnetic coils 44, 54 connected to each control power supply 47, and its energization together with the energization switch of the motor 3. Being controlled. In these configurations, the control power supply 47 is provided separately from the control power supply of the electric motor 3, and the introduction terminal 30 for drawing out the cables of the electromagnetic coils 44 and 54 from the sealed container 1 is also provided separately.
[0044]
In this embodiment, as shown in FIG. 5, the electromagnetic coil 62 of the back pressure communication hole opening / closing valve 61 is connected in series with one coil winding 64 of the electric motor 3 inside the hermetic container 1 of the compressor. Yes. When the electric motor 3 is energized from the control power supply 67 during operation of the scroll compressor, the electromagnetic coil 62 of the back pressure communication hole on / off valve 61 is also energized, and the back pressure communication hole on / off valve 61 is opened. Further, when the operation of the scroll compressor is stopped, the power supply from the control power supply 67 is cut off, so that the back pressure communication hole opening / closing valve 61 is closed along with the stop of the electric motor 3.
[0045]
According to the configuration of the third embodiment, the backflow of the lubricating oil at the time of stopping can be prevented as in the first and second examples, and the control power 67 of the motor 3 can also be used as the control power of the electromagnetic coil 62. In addition, it is not necessary to provide the introduction terminal 65 separately, and the reliability of the scroll compressor can be improved with a simpler and cheaper configuration than those of the first and second embodiments.
[0046]
In the third embodiment, the example in which the electromagnetic coil 62 is connected in series to the coil winding 64 is shown. However, for example, the electromagnetic coil 62 is connected in parallel between the U and V lines of the coil winding 64 in FIG. However, the same effect can be obtained. Further, the same effect as described above can be obtained even if the configuration is such that the induced voltage is applied from the U, V, and W lines.
[0047]
In addition, the connection method of the U, V, and W lines of the coil winding 64 may be other connection methods. Furthermore, the electric motor is not limited to one driven in three phases of U, V, and W, and the same effect as described above can be obtained even if the electric motor is driven in two or multiple phases or a DC motor. .
[0048]
In the first to third embodiments, the electromagnetic coil is used as the driving means for the back pressure communication hole opening / closing valve. However, other driving means such as an electric motor and a fluid machine may be used. The same effect as 1-3 is acquired.
[0049]
In the first to third embodiments, the elastic force by the spring is used as the restoring force of the back pressure communication hole opening / closing valve. For example, the magnetic force, the force received from a fluid such as refrigerant gas or lubricating oil, or Other restoring forces such as gravity may be used, and the same effect as in the first to third embodiments can be obtained.
[0050]
【The invention's effect】
Since the back pressure communication hole is closed when the compressor is stopped, the lubricating oil in the lubricating oil pool can be prevented from flowing back to the suction side, and the reduction of the lubricating oil can be prevented. A hermetic scroll compressor with high productivity and high reliability can be provided.
[0051]
In addition, the back pressure control valve and back pressure communication hole opening / closing means are integrated into a single unit, making it compact and reducing installation space, maintaining design flexibility, and reducing the number of parts, making it cheaper and simpler. The structure can improve assembly productivity.
[0052]
In addition, by connecting the electromagnetic coil of the back pressure communication hole opening / closing means and the coil of the motor in series or in parallel in a sealed container, it can be made compact with a simpler configuration, maintaining the degree of design freedom and the number of parts. Since it can be reduced, the cost can be reduced, and the assembly productivity can be improved with a simple structure.
[Brief description of the drawings]
FIG. 1 is an enlarged longitudinal sectional view of a main part of a scroll compressor according to Embodiment 1 of the present invention during operation. FIG. 2 is a main part of the scroll compressor according to Embodiment 1 of the present invention when operation is stopped. FIG. 3 is a longitudinal cross-sectional view enlarging a main part during operation of the scroll compressor according to the second embodiment of the present invention. FIG. 4 is a view of the scroll compressor according to the second embodiment of the present invention. Fig. 5 is an enlarged vertical cross-sectional view of the main part when the operation is stopped. Fig. 5 is a diagram for explaining connection in the third embodiment of the present invention. Fig. 6 is a vertical cross-sectional view of a conventional scroll compressor. Vertical section of the main part
DESCRIPTION OF SYMBOLS 1 Airtight container 2 Compression mechanism 3,63 Electric motor 4 Drive shaft 5 Lubricating oil reservoir 6 Orbiting scroll 7 Fixed scroll 8 Bearing frame 24 Back pressure chamber 25 Oil supply holes 30 and 65 Introduction terminal 31 Back pressure adjustment valve 32 Valve side communication hole 33 Steel Ball 34 Adjustment chamber 35 Spring 36 Cap 37 Suction side communication holes 41, 51, 61 Back pressure communication hole on / off valve 42, 52 Valve guide hole 43 Valve body 44, 54 Electromagnetic coil 45, 55 Spring 46 Holder 47, 67 Control power supply 53 Push member 64 Coil winding 65 Introduction terminal

Claims

In a sealed container, a compression mechanism portion composed of a fixed scroll and a turning scroll, a drive shaft for driving the compression mechanism portion, a bearing frame provided with a main bearing for supporting the drive shaft, and the drive shaft are driven to rotate. An electric motor is provided,
A back pressure communication hole communicating the back pressure space formed by the back surface of the orbiting scroll and the bearing frame and the suction chamber of the compression mechanism, and opening and closing the back pressure communication hole to reduce the pressure of the back pressure chamber. It has back pressure control means that makes the pressure between the suction pressure and the discharge pressure,
Lubricating oil in the lubricating oil reservoir is supplied to the back pressure chamber via the oil supply hole provided in the drive shaft and the main bearing sliding portion due to the pressure difference between the discharge pressure in the sealed container and the back pressure chamber. Further, in the scroll compressor further comprising an oil supply mechanism that supplies the compression mechanism portion via the back pressure communication hole due to a pressure difference between the back pressure chamber and the suction chamber.
A scroll compressor comprising a back pressure communication hole opening / closing means that opens the back pressure communication hole when the motor is in operation and closes the motor when the motor is stopped.

2. The scroll compressor according to claim 1, wherein the back pressure communication hole opening / closing means includes a valve body that opens and closes the back pressure communication hole and a valve body drive unit that drives the valve body to open and close.

The back pressure communication hole opening / closing means is configured integrally with the back pressure control means, the valve body serving also as the on / off valve of the back pressure control means in the previous period, the pressing member pressing the valve body toward the side where the back pressure communication hole is closed, and the electric motor 3. The scroll compressor according to claim 1, further comprising: a valve body drive unit that presses the valve body through the pressing member only when the engine is stopped and closes the back pressure communication hole. 4.

The scroll compressor according to any one of claims 1 to 3, wherein the valve body drive unit includes an electromagnetic coil, and the electromagnetic coil is connected in series or in parallel with the coil of the electric motor.

The scroll compressor according to any one of claims 1 to 4, wherein the electromagnetic coil and the coil of the electric motor are connected in a sealed container.