JP4300726B2

JP4300726B2 - Rotary gas compressor

Info

Publication number: JP4300726B2
Application number: JP2001288675A
Authority: JP
Inventors: 勝晴藤尾; 澤井　　清
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 2001-09-21
Filing date: 2001-09-21
Publication date: 2009-07-22
Anticipated expiration: 2021-09-21
Also published as: JP2003097471A

Description

【０００１】
【発明の属する技術分野】
本発明は回転式気体圧縮機の圧縮機構部の密封手段に関するものである。
【０００２】
【従来の技術】
昨今の地球環境保護問題に端を発して、従来から継続使用されているフロン冷媒に替わり自然冷媒、特に、二酸化炭素（ＣＯ２）冷媒を用いたヒートポンプシステムの研究開発が各分野で盛んに行われている。
【０００３】
しかしながら、従来のフロン冷媒を用いた冷凍サイクルでは、高圧側が３ＭＰａ以下であるのに対して、二酸化炭素（ＣＯ２）冷媒を用いた冷凍サイクルでは、低圧側が２．５〜５ＭＰａ，高圧側が１２〜１５ＭＰａにも達して高低圧力差が極めて大きく、圧縮機構部での高圧側から低圧側への気体漏れ損失の過大が懸念されている。
【０００４】
このような理由から、二酸化炭素（ＣＯ２）冷媒を用いた圧縮機として、隣接する圧縮室間の差圧を小さくできるスクロール圧縮機や多段圧縮機の改良検討が進められている。
【０００５】
特に、家庭用ヒートポンプシステムに搭載される圧縮機としては、生産性と耐久性および高性能・小型化の観点から多段圧縮機としては、密閉容器内が高圧型のローリングピストン型ロータリ式２段圧縮機が注目を浴びている。また、スクロール圧縮機としては圧縮機構部を収納する高圧密閉容器内が油分離機能を兼ね、別途に油分離器を要しない高圧型スクロール圧縮機が注目を浴びている。
【０００６】
図７は発明者が特開平４−１８７８８７号公報（特許第２７６８００４号公報）で提案したローリングピストン型ロータリ式２段圧縮機と冷凍サイクル配管系の接続図、図８は同圧縮機の縦断面図、図９は同圧縮機の部分縦断面図を示す。
【０００７】
図７〜図９において、従来のフロン系冷媒の吐出冷媒ガスが充満する密閉容器１００１内には電動機５、低段圧縮要素１００７と高段圧縮要素１００４と中板３６から成る２段圧縮機構が収納され、高段圧縮要素１００４のローリングピストン圧縮機構の高段ベーン１０３９の反シリンダ側には吐出圧力が作用する潤滑油３５が作用して高段ベーン１０３９の先端を高段ピストン１００９ｂに押圧している。一方、低段圧縮要素１００７のローリングピストン圧縮機構の低段ベーン１０３８の反シリンダ側には、油溜１０３５の潤滑油を中板１０３６に設けた絞り通路１０６１ａを有する給油通路１０６１を経由して中間圧力に減圧の後、低段ベーン背面室１０４４に導入された潤滑油が作用している。この付勢力によって、低段ベーン１０３８の先端が低段ピストン１００７ｂに押圧されてシリンダ内を吸入室と圧縮室とに区画する構成になっている。
【０００８】
なお、低段ベーン背面室１０４４に供給された潤滑油は、低段ベーン１０３８の摺動面を潤滑する一方、低段吐出室１０４５に流入した後、吐出冷媒ガスと共に連通路１０５５を経由して高段圧縮要素１００９の吸入側に吸い込まれ、圧縮の後、電動機室１００８に排出される。電動機室１００８で冷媒ガスから分離した潤滑油は油溜１０３５に収集される。
【０００９】
このように、高段ベーン１０３９の先端と高段ピストン１００９ｂとの接触力は、高段圧縮要素１００９の吐出圧力と高段圧縮要素１００９の吸入圧力（低段吐出圧力）との差圧力が作用する。また同様に、低段ベーン１０３８の先端と低段ピストン１００７ｂとの接触力は、低段圧縮要素１００７の吐出圧力と吸入圧力との差圧が作用する。したがって、低段ベーン１０３８の先端の摩擦損失動力や摩耗量が、高段吐出圧力と低段吸入圧力との差圧が作用する場合よりも半減する構成である。
【００１０】
このような構成のロータリ式２段圧縮機でＣＯ２冷媒ガスを使用する場合（吐出圧力と吸入圧力との差圧が極めて大きい状態）でも、高段ベーン１０３９や低段ベーン１０３８の先端に作用する荷重が半減するので摺動部の耐久性確保が可能となる。
【００１１】
【発明が解決しょうとする課題】
しかしながら、２段圧縮機構１００３の外周部の雰囲気圧力が吐出圧力相当のために潤滑油や冷媒ガスが、２段圧縮機構１００３の各圧縮室（シリンダ内）を形成するための構成部品間の接触固定面や摺動部隙間を介してシリンダ内に流入する漏洩量が多く、圧縮効率が著しく低下する課題があった。
【００１２】
なお、２段圧縮機構１００３の各圧縮室（シリンダ内）を形成するための構成部品間の接触固定面の間にシール部材を配置してシリンダ内への流体漏洩を防止する方策があるが、組立部品隙間の極めて小さい２段圧縮機構１００３の組立が困難である理由から上記の方策は実現不可能でもある。
【００１３】
図１０は、圧縮機構部の全体が高圧冷媒ガスや高圧潤滑油の雰囲気中にない場合のスクロール気体圧縮機の縦断面図を示す。
【００１４】
すなわち、モータ２００７に連結する駆動軸２００８を支持するフレーム２００３によって、密閉ケース２００１，２００２内が上部の吐出空間２０１３（高圧側）と下部のモータ室２０１５（低圧側）とに区画されている。吐出空間２０１３内に配置された鏡板２０１２はフレーム２００３に固定される一方、固定スクロール２０１１を固定している。固定スクロール２０１１に噛み合う旋回スクロール２０１０はフレーム２００３に支持されながら駆動軸２００８の偏心穴２００９に係合する。吐出空間２０１３の底部の吐出室油溜２０３６はフレーム２００３に設けられた極細通路２０１９を介してモータ室２０１５の底部の油溜２０１７に通じている構成である。
【００１５】
このような構成のスクロール気体圧縮機において、吐出室油溜２０３６の潤滑油は、鏡板２０１２および固定スクロール２０１１とフレーム２００３との接触固定面を通じて旋回スクロール（可動スクロール）２０１０の外側の吸入室２０３７に微小漏洩する。特に、冷凍サイクルにおける高圧側と低圧側との差圧が従来冷媒よりも極めて大きいＣＯ２冷媒ガスを使用する場合には、吐出室油溜２０３６と吸入室２０３７との差圧が大きいために吐出室油溜２０３６の潤滑油が吸入室２０３７に漏洩する量が多く、圧縮効率の著しい低下を招く課題があった。上述のロータリ式２段圧縮機で説明した場合と同様に、鏡板２０１２とフレーム２００３との接触固定面にシール部材を配置して吐出室油溜２０３６の潤滑油が吸入室２０３７に漏洩するのを防止する方策もあるが、鏡板２０１２とフレーム２００３との接触固定面にシール部材を配置することによって、圧縮室の微小隙間確保を要する旋回スクロール２０１０と固定スクロール２０１１の適正配置組立が困難であると言う理由から実現不可能である。
【００１６】
上記のような構成のスクロール気体圧縮機に限らず、例えば発明者が特公平７−７８３９１号公報で提案しているような、スクロール圧縮機構が高圧冷媒ガスや高圧潤滑油の雰囲気内に配置された構成のスクロール気体圧縮機の場合も同様の課題を有する。
【００１７】
本発明はこのような従来の課題を解決するものであり、圧縮機構部を囲む高圧流体（冷媒や潤滑油）が圧縮室内に流入漏洩するのを防止することを目的とするものである。
【００１８】
【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、圧縮機構部を囲む高圧雰囲気から組立済みの圧縮機構部を圧力的に遮断する手段を設けたものである。
【００１９】
上記遮断手段によって圧縮機構部を囲む高圧流体（冷媒や潤滑油）が圧縮室内に漏洩流入するのを阻止し、圧縮効率の低下防止を図ることができる。
【００２０】
【発明の実施の形態】
請求項１に記載の発明は、密閉容器内に電動機とその電動機に連結する圧縮機構部を収納し、圧縮機構部の圧縮気体を密閉容器内に排出する構成において、前記圧縮機構部は前記圧縮要素を低段圧縮要素と高段圧縮要素を順次直列接続した２段圧縮機構とし、それぞれの圧縮要素を連結すべく各圧縮要素に隣接して配置され且つ圧縮室の壁面構成の一部材
である中板の外周部を前記隔離手段で前記密閉容器内から圧力的に遮断するとともに、圧縮機構部の圧縮室を形成する構成部材間の結合面の外周部を密閉容器内から圧力的に遮断する隔離手段を設け、前記隔離手段は、低段圧縮要素の低段シリンダブロック、駆動軸を支持し且つ前記低段シリンダブロックと共に圧縮室を形成すべく前記低段シリンダブロックに固定された軸受部材、前記低段シリンダブロックと共に前記圧縮室を形成すべく前記低段シリンダブロックに隣接配置された中板の外周部を囲むべく環状部を備えた部材により構成したものである。
【００２１】
そしてこの構成によれば、密閉容器内の高圧（吐出圧力相当）流体（気体や潤滑油）が圧縮室を形成する構成部材間の結合面を介して圧縮室内に漏洩流入するのを阻止し、また、密閉容器内に吐出された流体（気体や潤滑油）が軸受部材と低段シリンダブロック、中板と低段シリンダブロックとの２箇所の接触固定面を介して低段圧縮要素の圧縮室の吸入側に漏洩流入するのを阻止し、著しい圧縮効率の低下防止を図れる。
【００２２】
請求項２に記載の発明は、隔離手段が、中板と高段圧縮要素の高段シリンダブロックとの接触固定面を密閉容器内から圧力的に遮断する手段を設けたものである。そしてこの構成によれば、密閉容器内の吐出流体（気体や潤滑油）が低段圧縮要素および高段圧縮要素の両圧縮室を形成すべく配置された構成部材の接触固定面を介して両圧縮室に漏洩流入するのを阻止し圧縮効率低下を防止できる。
【００２３】
請求項３に記載の発明は、隔離手段が、低段圧縮要素の低段吐出室を形成すべく低段圧縮要素の低段シリンダブロックの外周部を囲むように形成された吐出カバーを兼ねたものである。そしてこの構成によれば、低段圧縮要素を組立後に取り付けられた吐出カバーがその内部に圧縮室を配置する低段シリダブロックの外周部を密閉容器内の吐出流体雰囲気から遮断し、圧縮室への不要な漏洩流体流入を回避して圧縮効率の向上を図る。
【００２４】
【実施例】
以下本発明の実施例について図面を参照して説明する。
【００２５】
（実施例１）
図１は二酸化炭素（ＣＯ２）冷媒を使用したローリングピストン型ロータリ式２段圧縮機の縦断面を表し、図２は同圧縮機の部分縦断面を表し、図３は同圧縮機の低段シリンダブロックの外観図を表す。
【００２６】
密閉容器１の内部に、電動機２とその下部に２段圧縮機構３が配置されている。２段圧縮機構３は、高段圧縮要素４と、その下部に配置された低段圧縮要素５と、高段圧縮要素４および低段圧縮要素５の間に配置された中板６と、高段圧縮要素４および低段圧縮要素５を駆動すべく電動機２の回転子２ａに連結された駆動軸７と、駆動軸７を支持すべく高段圧縮要素４の高段シリンダブロック８に固定された主軸受９および低段圧縮要素５の低段シリンダブロック１０に固定された副軸受１１とから成る。
【００２７】
高段シリンダブロック８は密閉容器１に溶接固定され、その高段シリンダブロック８に中板６と低段シリンダブロック１０が固定されている。
【００２８】
主軸受９に取付られた高段吐出カバー１２は、主軸受９と共に高段吐出室１３を形成している。
【００２９】
中板６，低段シリンダブロック１０，副軸受１１の外周部を囲み且つシール部材９８を介して高段シリンダブロック８に取付られた低段吐出カバー２６の内部は低段吐出室２７を形成している。低段吐出カバー２６と副軸受１１との間にＯ―リング９７が介装され、密閉容器１内の油溜３２と低段吐出室２７との間が圧力的に隔離されている。
【００３０】
低段吐出室２７と高段吐出室１３との間は、副軸受１１，低段シリンダブロック１０，中板６，高段シリンダブロック８，主軸受９を貫通して設けられたバイパス通路９６で連通されている。バイパス通路９６の端部は、バイパス通路９６を開閉する弁体９５と、弁体９５を付勢するバネ手段９４が配置されており、低段吐出室２７から高段吐出室１３への冷媒ガスの流入のみ許容する逆止弁機構を形成している。
【００３１】
駆動軸７を貫通する油穴７ａの下端部には、遠心ポンプ手段９３が装着されており、遠心ポンプ手段９３によって、副軸受１１、低段圧縮要素５の低段ピストン７０の内側、高段圧縮要素４の高段ピストン６５の内側、主軸受９の各摺動面に油溜３２の潤滑油が給油される経路が形成されている。
【００３２】
高段圧縮要素４のシリンダ内で高段ピストン６５の外周面に接してシリンダ内を吸入室と圧縮室とに区画すべく配置された高段ベーン１５の反シリンダ側の高段ベーン背面室１６は、油溜３２に連通している。
【００３３】
上記と同様に、低段圧縮要素５の低段ベーン９２の反シリンダ側に配置された低段ベーン背面室３３にはバネ手段（コイルバネ）９１が配置され、低段ベーン９２の先端を低段ピストン７０に押圧付勢している。バネ手段（コイルバネ）９１を装着すべく低段ベーン背面室３３に設けられたバネ装着穴３４は、以下に述べる経路を経て密閉容器１内の油溜３２に連通している。
【００３４】
すなわち、バネ装着穴３４は、低段シリンダブロック１０と中板６の外周部と低段吐出カバー２６との間の間隙通路９０、中板６に設けられて絞り部を有する油穴６８、駆動軸７の油穴７ａに直交して設けられた半径方向油穴７ｂを順次経由して連通している。
【００３５】
また、低段ベーン背面室３３は、バネ装着穴３４よりも上部に流出口８９を有する給油路８８を介して低段吐出室２７に連通している。
【００３６】
低段吐出室２７は、副軸受１１，高段シリンダブロック１０，中板６を貫通して設けられた中間連通路８７を介して高段圧縮要素４の吸入室に通じている。
【００３７】
密閉容器１の上壁中央部の平坦部には電動機２に接続する電気接続端子８６が配置され、その外部接続端子８６ａには、絶縁樹脂材で結束した外部接続クラスター８５が挿入されている。その外部接続クラスター８５を囲むターミナルカバー８４の内形状は、例えば、電気接続端子８６を構成する端子が密閉容器１内の高圧ＣＯ２ガス圧力によって部分的に抜けようとする場合でも、外部接続クラスター８５が外部接続端子８６ａから外れることがないように設定されている。
【００３８】
密閉容器１の上壁に配置された吐出管８３の電動機室２９側開口端の近傍には、密閉容器１の内壁側に開口した遮蔽板８２が配置されており、電気接続端子８６の側から吐出管８３への直接的なガス流出を防でいる。
【００３９】
以上のように構成された二酸化炭素（ＣＯ２）冷媒ガスを使用したローリングピストン型ロータリ式２段圧縮機について、図１、図２、図３を参照しながらその動作を説明する。
【００４０】
低段圧縮要素５のシリンダ内に取り込まれた吸入冷媒ガスは、圧縮された後、低段吐出室２７に吐出される。低段吐出室２７の吐出冷媒ガスは、中間連通路８７を経由して高段圧縮要素４の吸入室に取り込まれ、圧縮の後、高段吐出室１３に吐出され、電動機室９に排出される。電動機室９に排出された冷媒ガスに混入する潤滑油の一部は分離され、油溜３２に収集される。潤滑油の一部が分離された高圧の吐出冷媒ガスは、吐出管８３を経て圧縮機外部配管系に送出される。
【００４１】
高段圧縮要素４の吐出冷媒ガス圧力が作用する油溜３２の潤滑油は、駆動軸７の下端部に配置された遠心ポンプ手段９３によって駆動軸７内の油穴７ａ，半径方向油穴７ｂ，低段ピストン７０の内径側空間，高段ピストン６５の内径側空間，主軸受９の軸受摺動面を順次経由して電動機室２９に排出され、再び、油溜３２に帰還する。
【００４２】
なお、遠心ポンプ手段９３から駆動軸７内の油穴７ａに排出された潤滑油に混入する冷媒ガスが油穴７ａの上部開口端から電動機室２９へ放出される。それによって、油穴７ａの潤滑油がガス抜きされるので、低段ピストン７０の内径摺動面，高段ピストン６５の内径摺動面，主軸受９の軸受摺動面にはガス噛み込みのない良好な油膜が形成される。
【００４３】
このような駆動軸７の摺動部給油過程途中の潤滑油は、中板６の絞り部を有する油穴６８を介して中間圧力に減圧の後、間隙通路９０，バネ装着穴３４，低段ベーン背面室３３，バネ装着穴３４よりも上部の流出口８９，中間連通路８７を順次経由して低段吐出室２７に供給される。中間連通路８７は絞り作用が生じることのない通路であるために、低段ベーン背圧室３３は低段吐出室２７と相当圧力となる。
【００４４】
低段ベーン背圧室３３と低段吐出室２７を連通する中間連通路８８の流出口８９がバネ装着穴３４よりも上部配置であるために、圧縮機停止中でも低段ベーン背圧室３３の潤滑油がその自重により低段吐出室２７に流出することなく、圧縮機再起動初期における低段ベーン９２の摺動部隙間の潤滑に提供される。
【００４５】
当然のことながら、圧縮機運転中も低段ベーン背圧室３３の潤滑油が十分に確保されて、低段ベーン９２の摺動部隙間の油膜密封作用と、低段ベーン９２を低段ピストンに押圧させる。
【００４６】
この押圧力は、低段ベーン背面室３３に油溜３２の潤滑油が減圧されることなく導入される場合に比較して半減しており、低段ピストン７０の外周面と低段ベーン９２の先端との摺動摩擦損失が小さく、摺動部摩耗も少ない特徴を有している。
【００４７】
また、高段シリンダブロック８と低段吐出カバー２６の間に介在するシール部材によって、低段ベーン背面室３３が密閉容器１内と圧力的に隔離されており、例え、油溜３２の油面が低下する場合でも、密閉容器１内の吐出冷媒ガスが低段ベーン背面室３３に漏洩することはない。また、密閉容器１内の吐出冷媒ガスや吐出圧力が作用する潤滑油が中板６と高段シリンダブロック８との接触結合面、中板６と低段シリンダブロック１０との接触結合面を介して高段圧縮要素４の圧縮室および低段圧縮要素５の圧縮室に直接的に漏洩流入することはない。
【００４８】
低段ベーン背面室３３から低段吐出室２７を経由して高段圧縮要素４の吸入室に導入された適量の潤滑油は、高段圧縮要素４の圧縮室隙間の油膜密封作用に供され、圧縮効率を向上させる。
【００４９】
以上のように上記実施例によれば、密閉容器１内に電動機２と電動機２に連結する圧縮機構部を収納し、その圧縮機構部３ａの圧縮気体を密閉容器１内に排出する構成において、圧縮機構部３ａの圧縮室を形成する構成部材（高段シリンダブロック８と中板６、低段シリンダブロック１０と中板６）間の結合面の外周部を密閉容器１内から圧力的に遮断する隔離手段（高段シリンダブロック８と中板６と低段シリンダブロック１０と副軸受１１を囲む低段吐出カバー２６がシール部材９８を介して高段シリンダブロック８に取付られた状態）を設けたことにより、密閉容器１内の高圧（吐出圧力相当）流体（吐出冷媒ガスや潤滑油）が圧縮室を形成する構成部材間の接触結合面を介して圧縮室内に漏洩流入するのを阻止し、圧縮効率の低下防止を図ることができる。
【００５０】
また上記実施例によれば、圧縮機構部３ａは複数の圧縮要素（低段圧縮要素５、高段圧縮要素４）から成り、それぞれの圧縮要素を連結すべく各圧縮要素に隣接して配置され且つ圧縮室の壁面構成一部材である中板６の外周部を囲む形態で低段吐出カバー２６を配置して密閉容器１内から圧力的に遮断したことにより、中板６と各圧縮要素（４、５）の隣接面を介して密閉容器１内の高圧流体（吐出冷媒ガスや潤滑油）が圧縮室内に漏洩流入するのを回避し、圧縮効率の低下防止を図ることができる。
【００５１】
また上記実施例によれば、圧縮要素を低段圧縮要素５と高段圧縮要素４を順次直列接続した２段圧縮機構３としたことにより、密閉容器１内の吐出冷媒ガスや潤滑油が中板６を介して低段圧縮要素５および高段圧縮要素４の圧縮室の吸入側に漏洩流入するのを防止し、高段圧縮要素４における圧縮損失の発生を防止すると共に、低段圧縮要素５から高段圧縮要素４への圧縮損失の巡送りを回避して、圧縮効率の大幅な低下を防止することができる。
【００５２】
また上記実施例によれば、低段圧縮要素５の構成部品の外周部を密閉容器１内から圧力的に遮断する隔離手段を設けたことにより、密閉容器１内の吐出冷媒ガスや潤滑油が中板６を介して低段圧縮要素５の圧縮室の吸入側（低圧側）に漏洩流入し、高段圧縮要素４でも再び漏洩流体が再圧縮されることによる過剰な圧縮損失発生の防止を図ることができる。
【００５３】
また上記実施例によれば、隔離手段は、低段圧縮要素５の低段シリンダブロック１０、駆動軸７を支持し且つ低段シリンダブロック１０と共に圧縮室を形成すべく低段シリンダブロック１０に固定された副軸受１１、低段シリンダブロック１０と共に圧縮室を形成すべく低段シリンダブロック１０に隣接配置された中板６の外周部を囲むべく環状部を備えた低段吐出カバー２６としたことにより、密閉容器１内に吐出された流体（吐出冷媒ガスや潤滑油）が副軸受１１と低段シリンダブロック１０、中板６と低段シリンダブロック１０との２箇所の接触固定面を介して低段圧縮要素５の圧縮室の吸入側に漏洩流入するのを阻止し、著しい圧縮効率の低下を防止することがきる。
【００５４】
また上記実施例によれば、隔離手段は、中板６と高段圧縮要素４の高段シリンダブロック８との接合面を密閉容器１内から圧力的に遮断する手段を設けたことにより、密閉容器１内の吐出流体（吐出冷媒ガスや潤滑油）が低段圧縮要素５および高段圧縮要素４の両圧縮室を形成すべく配置された構成部材の接触固定面を介して両圧縮室に漏洩流入するのを阻止し圧縮効率低下を防止することができる。
【００５５】
また上記実施例によれば、隔離手段は、低段圧縮要素５の低段吐出室２７を形成すべく低段圧縮要素５の低段１０シリンダブロックの外周部を囲むように形成された低段吐出カバー２６を兼ねたことにより、低段圧縮要素５を組立後に取り付けられた低段吐出カバー２６がその内部に圧縮室を配置する低段シリダブロック１０の外周部を密閉容器１内の吐出冷媒ガスや潤滑油から遮断し、圧縮室への不要な漏洩流体流入を回避して圧縮効率の向上を図ることができる。
【００５６】
なお、上記実施例では、中板６の中間連通路８７と低段ベーン背面室３３との間を間隙通路９０を介して連通したが、間隙通路９０を介することなく直接的に連通しても良い。
そして、低段シリンダブロック１０との接触結合面の外周部にシール部材を配置して、密閉容器１内の吐出冷媒ガスや潤滑油と圧縮室との間を完全に隔離密封し、圧縮室への流体漏洩を回避することによる圧縮効率の向上を図ることができる。
【００５７】
（実施例２）
図４は密閉容器１内が二酸化炭素（ＣＯ２）の吐出冷媒ガスで充満するスクロール圧縮機の縦断面を示す。
【００５８】
電動機（モータ）３０１０に連結する駆動軸３００５を支持する本体フレーム３００２に固定スクロール３０３４が締結されている。固定スクロール３０３４に噛み合う旋回スクロール３０１４は本体フレーム３００２に支持されながら背圧室３０２０に配置され、駆動軸３００５の先端の偏心軸部３００８と、本体フレーム３００２に係止された自転阻止機構とに係合して旋回運動する。固定スクロール３０３４と旋回スクロール３０１４とが噛み合って形成する圧縮空間は、その外側部が吸入管３０２８に通じる吸入室３０２２を構成し、その中央部の圧縮室が吐出ポート３０２５に通じる。背圧室３０２０は絞り機能を有するバランス通路３０２６を介して吸入室３０２２に通じている。
【００５９】
固定スクロール３０３４の鏡板３０２１には吐出カバー３０９９が取付られて吐出室３０２４を形成する。吐出カバー３０９９は鏡板３０２１と本体フレーム３００２の外周部を囲む形態で配置されている。
【００６０】
固定スクロール３０３４の鏡板３０２１と本体フレーム３００２との締結外周部と、吐出カバー３０９９との間にＯ―リング３０９８が押圧介装され、密閉容器１内の吐出冷媒ガスが本体フレーム３００２の内部側（背圧室３０２０）に流入するのを防止している。
【００６１】
このような構成において、吸入室３０２２が３ＭＰａ，吐出室３０２４が１０ＭＰａ，背圧室が５ＭＰａの圧力状態を維持してスクロール圧縮機が運転される。密閉容器１内の冷媒ガスは、Ｏーリング３０９８のシール機能によって背圧室３０２０を経由する吸入室３０２２への漏洩流入を阻止される。これによって、圧縮効率の低下が防止され、高効率なスクロール圧縮機を提供する。
【００６２】
（実施例３）
図６は、固定スクロールの鏡板３０２１ａと本体フレーム３００２ａの締結面外周部に突起状部３０２１ｂと突起状部３００２ｂを設け、その隣接外周部をレーザ溶接等の集中溶接接合することにより、図５におけるＯーリング３０９８のシール機能に置き換えたスクロール圧縮機の部分断面図を示す。レーザ溶接等の集中溶接接合は、鏡板３０２１ａと本体フレーム３００２ａを溶接時の熱変形を伴うことなく溶接接合できる。また、鏡板３０２１ａと本体フレーム３００２ａの材質がアルミニューム合金等の場合の集中溶接接合には、電子ビーム溶接が適している。
【００６３】
なお、上記実施例では二酸化炭素冷媒を使用したローリングピストン型ロータリ式２段圧縮機およびスクロール圧縮機について説明したが、他の気体（例えば、酸素，窒素，ヘリウム，空気など）を圧縮する２段ローリングピストン型ロータリ式圧縮機およびスクロール圧縮機の場合も同様な作用・効果を生じるものである。
【００６４】
【発明の効果】
上記実施例から明かなように、請求項１に記載の発明は、密閉容器内に電動機とその電動機に連結する圧縮機構部を収納し、圧縮機構部の圧縮気体を密閉容器内に排出する構成において、前記圧縮機構部は前記圧縮要素を低段圧縮要素と高段圧縮要素を順次直列接続した２段圧縮機構とし、それぞれの圧縮要素を連結すべく各圧縮要素に隣接して配置され且つ圧縮室の壁面構成の一部材である中板の外周部を前記隔離手段で前記密閉容器内から圧力的に遮断するとともに、圧縮機構部の圧縮室を形成する構成部材間の結合面の外周部を密閉容器内から圧力的に遮断する隔離手段を設け、前記隔離手段は、低段圧縮要素の低段シリンダブロック、駆動軸を支持し且つ前記低段シリンダブロックと共に圧縮室を形成すべく前記低段シリンダブロックに固定された軸受部材、前記低段シリンダブロックと共に前記圧縮室を形成すべく前記低段シリンダブロックに隣接配置された中板の外周部を囲むべく環状部を備えた部材により構成したものである。
【００６５】
そしてこの構成によれば、密閉容器内の高圧（吐出圧力相当）流体（気体や潤滑油）が圧縮室を形成する構成部材間の結合面を介して圧縮室内に漏洩流入するのを阻止でき、また、密閉容器内に吐出された流体（気体や潤滑油）が軸受部材と低段シリンダブロック、中板と低段シリンダブロックとの２箇所の接触固定面を介して低段圧縮要素の圧縮室の吸入側に漏洩流入するのを阻止し、著しい圧縮効率が低下するのを防止できる。
【００６６】
請求項２に記載の発明は、密閉容器内に電動機とその電動機に連結する圧縮機構部を収納し、圧縮機構部の圧縮気体を密閉容器内に排出する構成において、圧縮機構部の圧縮室を形成する構成部材間の結合面の外周部を密閉容器内から圧力的に遮断する隔離手段を設けると共に、圧縮機構部が複数の圧縮要素から成り、それぞれの圧縮要素を連結すべく各圧縮要素に隣接して配置され且つ圧縮室の壁面構成一部材である中板の外周部を隔離手段で密閉容器内から圧力的に遮断し、圧縮要素を低段圧縮要素と高段圧縮要素を順次直列接続した２段圧縮機構とし、その低段圧縮要素の構成部品の外周部を密閉容器内から圧力的に遮断する隔離手段を設け、その隔離手段は、低段圧縮要素の低段シリンダブロック、駆動軸を支持し且つ低段シリンダブロックと共に圧縮室を形成すべく低段シリンダブロックに固定された軸受部材、低段シリンダブロックと共に圧縮室を形成すべく低段シリンダブロックに隣接配置された中板の外周部を囲むべく環状部を備えた部材とし、隔離手段が、中板と高段圧縮要素の高段シリンダブロックとの接合面を密閉容器内から圧力的に遮断する手段を設けたものである。そしてこの構成によれば、密閉容器内の吐出流体（気体や潤滑油）が低段圧縮要素および高段圧縮要素の両圧縮室を形成すべく配置された構成部材の接触固定面を介して両圧縮室に漏洩流入するのを阻止し圧縮効率低下を防止できる。
【００６７】
請求項３に記載の発明は、密閉容器内に電動機とその電動機に連結する圧縮機構部を収納し、圧縮機構部の圧縮気体を密閉容器内に排出する構成において、圧縮機構部の圧縮室を形成する構成部材間の結合面の外周部を密閉容器内から圧力的に遮断する隔離手段を設けると共に、圧縮機構部が複数の圧縮要素から成り、それぞれの圧縮要素を連結すべく各圧縮要素に隣接して配置され且つ圧縮室の壁面構成一部材である中板の外周部を隔離手段で密閉容器内から圧力的に遮断し、圧縮要素を低段圧縮要素と高段圧縮要素を順次直列接続した２段圧縮機構とし、その低段圧縮要素の構成部品の外周部を密閉容器内から圧力的に遮断する隔離手段を設け、その隔離手段は、低段圧縮要素の低段吐出室を形成すべく低段圧縮要素の低段シリンダブロックの外周部を囲むように形成された吐出カバーを兼ねたものである。そしてこの構成によれば、低段圧縮要素を組立後に吐出カバーを取り付け、その内部に圧縮室を配置する低段シリダブロックの外周部を密閉容器内の吐出流体雰囲気から遮断するので、圧縮機構部の組立が容易で、且つ、圧縮室への不要な漏洩流体流入を回避でき、圧縮効率の向上を図ることができる。
【図面の簡単な説明】
【図１】本発明の第１の実施例を示すローリングピストン型ロータリ式２段圧縮機の縦断面図
【図２】同圧縮機における圧縮機構部の部分断面図
【図３】同圧縮機における高段シリンダブロックの外観図
【図４】本発明の第２の実施例を示すスクロール圧縮機の縦断面図
【図５】同圧縮機におけるシール部を示す部分断面図
【図６】本発明の第３の実施例を示すスクロール圧縮機のシール部を表す部分断面図
【図７】従来のローリングピストン型ロータリ式２段圧縮機と冷凍サイクル配管系の接続図
【図８】同圧縮機の縦断面図
【図９】同圧縮機の部分縦断面図
【図１０】従来のスクロール圧縮機の縦断面図
【符号の説明】
１密閉容器
２電動機
３２段圧縮機構
３ａ圧縮機構部
４高段側圧縮要素
５低段側圧縮要素
６中板
７駆動軸
８高段シリンダブロック
１０低段シリンダブロック
２６低段吐出カバー
２７低段吐出室
３００１密閉容器
３００２本体フレーム
３００２ａ突起状部
３００３主軸受
３０１３旋回軸受部
３０１４旋回スクロール
３０１４ａ旋回スクロールラップ
３０１４ｂラップ支持円盤
３０２１鏡板
３０２１ｂ突起状部
３０２２吸入室
３０２４吐出室
３０２５吐出ポート
３０３４固定スクロール
３０３４ａ固定スクロールラップ
３０９７スクロール式圧縮機構
３０９８シール部材（Ｏ―リング）
３０９９吐出カバー[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a sealing means for a compression mechanism portion of a rotary gas compressor.
[0002]
[Prior art]
  Rising from recent global environmental protection problems, research and development of heat pump systems using natural refrigerants, especially carbon dioxide (CO2) refrigerants, in place of CFC refrigerants that have been used continuously has been actively conducted in various fields. ing.
[0003]
  However, in the refrigeration cycle using the conventional chlorofluorocarbon refrigerant, the high pressure side is 3 MPa or less, whereas in the refrigeration cycle using the carbon dioxide (CO2) refrigerant, the low pressure side is 2.5 to 5 MPa and the high pressure side is 12 to 15 MPa. The pressure difference between the high pressure and the low pressure is extremely large, and there is a concern about excessive gas leakage loss from the high pressure side to the low pressure side in the compression mechanism.
[0004]
  For these reasons, as a compressor using carbon dioxide (CO 2) refrigerant, improvement studies of a scroll compressor and a multistage compressor that can reduce the differential pressure between adjacent compression chambers are being promoted.
[0005]
  In particular, as a compressor installed in a heat pump system for home use, from the viewpoint of productivity, durability, high performance and downsizing, a multistage compressor is a high-pressure rolling piston type rotary two-stage compression inside a sealed container. The machine is attracting attention. Further, as a scroll compressor, a high-pressure scroll compressor that has an oil separation function inside the high-pressure sealed container that houses the compression mechanism and does not require a separate oil separator has attracted attention.
[0006]
  FIG. 7 is a connection diagram of a rolling piston type rotary two-stage compressor proposed by the inventor in Japanese Patent Application Laid-Open No. 4-187878 (Patent No. 2768004) and a refrigeration cycle piping system, and FIG. 8 is a longitudinal section of the compressor. 9 and 9 are partial longitudinal sectional views of the compressor.
[0007]
  7 to 9, a two-stage compression mechanism including an electric motor 5, a low-stage compression element 1007, a high-stage compression element 1004, and an intermediate plate 36 is contained in a sealed container 1001 filled with a refrigerant gas discharged from a conventional fluorocarbon refrigerant. The lubricating oil 35 on which the discharge pressure acts acts on the opposite cylinder side of the high-stage vane 1039 of the rolling piston compression mechanism of the high-stage compression element 1004 to press the tip of the high-stage vane 1039 against the high-stage piston 1009b. ing. On the other hand, on the opposite cylinder side of the low-stage vane 1038 of the rolling piston compression mechanism of the low-stage compression element 1007, an intermediate is provided via an oil supply passage 1061 having a throttle passage 1061 a provided with lubricating oil in an oil reservoir 1035 in the intermediate plate 1036. After the pressure is reduced, the lubricating oil introduced into the low-stage vane back chamber 1044 acts. With this urging force, the tip of the low stage vane 1038 is pressed by the low stage piston 1007b, and the inside of the cylinder is partitioned into a suction chamber and a compression chamber.
[0008]
  The lubricating oil supplied to the low-stage vane back chamber 1044 lubricates the sliding surface of the low-stage vane 1038 and flows into the low-stage discharge chamber 1045 and then passes through the communication passage 1055 together with the discharged refrigerant gas. It is sucked into the suction side of the high-stage compression element 1009 and is discharged into the electric motor room 1008 after compression. Lubricating oil separated from the refrigerant gas in the electric motor chamber 1008 is collected in an oil reservoir 1035.
[0009]
  As described above, the contact force between the tip of the high stage vane 1039 and the high stage piston 1009b is a pressure difference between the discharge pressure of the high stage compression element 1009 and the suction pressure (low stage discharge pressure) of the high stage compression element 1009. To do. Similarly, the contact force between the tip of the low stage vane 1038 and the low stage piston 1007b is the differential pressure between the discharge pressure and the suction pressure of the low stage compression element 1007. Therefore, the friction loss power and the amount of wear at the tip of the low stage vane 1038 are halved as compared with the case where the differential pressure between the high stage discharge pressure and the low stage suction pressure acts.
[0010]
  Even when the CO2 refrigerant gas is used in the rotary type two-stage compressor having such a configuration (when the differential pressure between the discharge pressure and the suction pressure is extremely large), it acts on the tips of the high-stage vane 1039 and the low-stage vane 1038. Since the load is halved, the durability of the sliding portion can be ensured.
[0011]
[Problems to be solved by the invention]
  However, since the atmospheric pressure at the outer peripheral portion of the two-stage compression mechanism 1003 is equivalent to the discharge pressure, the lubricating oil and the refrigerant gas contact between the components for forming each compression chamber (inside the cylinder) of the two-stage compression mechanism 1003. There was a large amount of leakage flowing into the cylinder through the fixed surface and the sliding portion gap, and there was a problem that the compression efficiency was remarkably lowered.
[0012]
  There is a measure to prevent fluid leakage into the cylinder by disposing a seal member between the contact fixing surfaces between the components for forming each compression chamber (inside the cylinder) of the two-stage compression mechanism 1003. The above-mentioned measures are not feasible because it is difficult to assemble the two-stage compression mechanism 1003 having a very small assembly part gap.
[0013]
  FIG. 10 is a longitudinal sectional view of the scroll gas compressor when the entire compression mechanism is not in an atmosphere of high-pressure refrigerant gas or high-pressure lubricating oil.
[0014]
  That is, the frame 2003 that supports the drive shaft 2008 connected to the motor 2007 divides the sealed case 2001, 2002 into an upper discharge space 2013 (high pressure side) and a lower motor chamber 2015 (low pressure side). The end plate 2012 disposed in the discharge space 2013 is fixed to the frame 2003, and the fixed scroll 2011 is fixed. The orbiting scroll 2010 that meshes with the fixed scroll 2011 is engaged with the eccentric hole 2009 of the drive shaft 2008 while being supported by the frame 2003. A discharge chamber oil reservoir 2036 at the bottom of the discharge space 2013 is configured to communicate with an oil reservoir 2017 at the bottom of the motor chamber 2015 via an extra-fine passage 2019 provided in the frame 2003.
[0015]
  In the scroll gas compressor having such a configuration, the lubricating oil in the discharge chamber oil reservoir 2036 is transferred to the suction chamber 2037 outside the orbiting scroll (movable scroll) 2010 through the contact fixed surface between the end plate 2012 and the fixed scroll 2011 and the frame 2003. Small leak. In particular, when using CO2 refrigerant gas in which the differential pressure between the high pressure side and the low pressure side in the refrigeration cycle is much larger than that of the conventional refrigerant, the discharge chamber has a large differential pressure between the discharge chamber oil reservoir 2036 and the suction chamber 2037. There is a large amount of the lubricating oil in the oil reservoir 2036 leaking into the suction chamber 2037, and there is a problem in that the compression efficiency is significantly reduced. As in the case of the rotary type two-stage compressor described above, a seal member is disposed on the contact fixing surface between the end plate 2012 and the frame 2003 so that the lubricant in the discharge chamber oil reservoir 2036 leaks into the suction chamber 2037. Although there is a measure to prevent this, it is difficult to properly arrange and assemble the orbiting scroll 2010 and the fixed scroll 2011 that require a minute clearance in the compression chamber by arranging the seal member on the contact fixing surface between the end plate 2012 and the frame 2003. It is impossible to realize for the reason.
[0016]
  Not only the scroll gas compressor configured as described above, but also a scroll compression mechanism as proposed by the inventors in Japanese Patent Publication No. 7-78391 is arranged in an atmosphere of high-pressure refrigerant gas or high-pressure lubricating oil. The scroll gas compressor having the above configuration has the same problem.
[0017]
  The present invention solves such a conventional problem, and an object of the present invention is to prevent a high-pressure fluid (refrigerant or lubricating oil) surrounding a compression mechanism from flowing into and leaking into a compression chamber.
[0018]
[Means for Solving the Problems]
  In order to solve the above problems, the present invention is provided with means for pressure-blocking the assembled compression mechanism from the high-pressure atmosphere surrounding the compression mechanism.
[0019]
  The blocking means prevents the high-pressure fluid (refrigerant or lubricating oil) surrounding the compression mechanism from leaking into the compression chamber, thereby preventing the compression efficiency from being lowered.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
  The invention according to claim 1 is a configuration in which an electric motor and a compression mechanism connected to the electric motor are housed in a sealed container, and the compressed gas of the compression mechanism is discharged into the sealed container.The compression mechanism section is a two-stage compression mechanism in which the compression element is connected in series with a low-stage compression element and a high-stage compression element, and is arranged adjacent to each compression element so as to connect the compression elements. One member of wall structure
And the outer peripheral portion of the intermediate plate is pressure-blocked from the inside of the sealed container by the isolation means,Isolation means for pressure-blocking the outer peripheral portion of the joint surface between the constituent members forming the compression chamber of the compression mechanism portion from the inside of the sealed containerThe separating means includes a low-stage cylinder block of a low-stage compression element, a bearing member that supports the drive shaft and is fixed to the low-stage cylinder block so as to form a compression chamber together with the low-stage cylinder block, and the low-stage cylinder In order to form the compression chamber together with the block, it is constituted by a member provided with an annular portion so as to surround the outer peripheral portion of the intermediate plate arranged adjacent to the low-stage cylinder block.It is a thing.
[0021]
  And according to this configuration, the high-pressure (equivalent to discharge pressure) fluid (gas or lubricating oil) in the sealed container is prevented from leaking into the compression chamber via the coupling surface between the constituent members forming the compression chamber,Further, the fluid (gas or lubricating oil) discharged into the sealed container is a compression chamber of the low-stage compression element through two contact fixing surfaces of the bearing member and the low-stage cylinder block, and the middle plate and the low-stage cylinder block. Prevents leakage into the suction side of theThe reduction in compression efficiency can be prevented.
[0022]
  Claim2In the invention described in (1), the isolation means is provided with means for pressure-blocking the contact fixing surface between the middle plate and the high-stage cylinder block of the high-stage compression element from the inside of the sealed container. According to this configuration, the discharged fluid (gas or lubricating oil) in the hermetic container is both connected via the contact fixing surfaces of the constituent members arranged to form both the compression chambers of the low-stage compression element and the high-stage compression element. It is possible to prevent leakage from flowing into the compression chamber and prevent a reduction in compression efficiency.
[0023]
  Claim3In the invention described in (2), the separating means also serves as a discharge cover formed so as to surround the outer periphery of the low-stage cylinder block of the low-stage compression element so as to form a low-stage discharge chamber of the low-stage compression element. . According to this configuration, the discharge cover attached after the assembly of the low-stage compression element blocks the outer periphery of the low-stage cylinder block in which the compression chamber is disposed from the discharge fluid atmosphere in the sealed container, and enters the compression chamber. To improve the compression efficiency by avoiding unnecessary leakage fluid inflow.
[0024]
【Example】
  Embodiments of the present invention will be described below with reference to the drawings.
[0025]
  Example 1
  1 shows a longitudinal section of a rolling piston type rotary two-stage compressor using carbon dioxide (CO2) refrigerant, FIG. 2 shows a partial longitudinal section of the compressor, and FIG. 3 shows a low-stage cylinder of the compressor. An external view of the block is shown.
[0026]
  Inside the hermetic container 1, an electric motor 2 and a two-stage compression mechanism 3 are disposed below the electric motor 2. The two-stage compression mechanism 3 includes a high-stage compression element 4, a low-stage compression element 5 disposed below the high-stage compression element 4, a middle plate 6 disposed between the high-stage compression element 4 and the low-stage compression element 5, A drive shaft 7 connected to the rotor 2a of the electric motor 2 to drive the stage compression element 4 and the low stage compression element 5, and a high stage cylinder block 8 of the high stage compression element 4 to support the drive shaft 7 are fixed. And a secondary bearing 11 fixed to the low-stage cylinder block 10 of the low-stage compression element 5.
[0027]
  The high stage cylinder block 8 is fixed to the hermetic container 1 by welding, and the middle plate 6 and the low stage cylinder block 10 are fixed to the high stage cylinder block 8.
[0028]
  The high-stage discharge cover 12 attached to the main bearing 9 forms a high-stage discharge chamber 13 together with the main bearing 9.
[0029]
  A low-stage discharge chamber 27 is formed inside the low-stage discharge cover 26 that surrounds the outer periphery of the middle plate 6, the low-stage cylinder block 10, and the auxiliary bearing 11 and is attached to the high-stage cylinder block 8 via a seal member 98. ing. An O-ring 97 is interposed between the low stage discharge cover 26 and the auxiliary bearing 11, and the oil reservoir 32 in the hermetic container 1 and the low stage discharge chamber 27 are isolated from each other by pressure.
[0030]
  Between the low-stage discharge chamber 27 and the high-stage discharge chamber 13 is a bypass passage 96 provided through the auxiliary bearing 11, the low-stage cylinder block 10, the middle plate 6, the high-stage cylinder block 8, and the main bearing 9. It is communicated. At the end of the bypass passage 96, a valve body 95 that opens and closes the bypass passage 96 and a spring means 94 that biases the valve body 95 are disposed, and the refrigerant gas from the low stage discharge chamber 27 to the high stage discharge chamber 13 is disposed. The check valve mechanism that allows only the inflow of is formed.
[0031]
  Centrifugal pump means 93 is attached to the lower end of the oil hole 7 a that penetrates the drive shaft 7. By the centrifugal pump means 93, the auxiliary bearing 11, the inside of the low stage piston 70 of the low stage compression element 5, the high stage. A path through which the lubricating oil in the oil reservoir 32 is supplied is formed inside the high-stage piston 65 of the compression element 4 and on each sliding surface of the main bearing 9.
[0032]
  The high-stage vane back chamber 16 on the side opposite to the cylinder of the high-stage vane 15 disposed to contact the outer peripheral surface of the high-stage piston 65 in the cylinder of the high-stage compression element 4 and partition the inside of the cylinder into a suction chamber and a compression chamber. Communicates with the oil reservoir 32.
[0033]
  Similarly to the above, a spring means (coil spring) 91 is arranged in the low-stage vane back chamber 33 arranged on the side opposite to the cylinder of the low-stage vane 92 of the low-stage compression element 5, and the tip of the low-stage vane 92 is arranged at the low stage. The piston 70 is pressed and urged. A spring mounting hole 34 provided in the low-stage vane back chamber 33 for mounting a spring means (coil spring) 91 communicates with the oil reservoir 32 in the hermetic container 1 through a path described below.
[0034]
  That is, the spring mounting hole 34 is a gap passage 90 between the lower stage cylinder block 10 and the outer peripheral part of the middle plate 6 and the lower stage discharge cover 26, an oil hole 68 provided in the middle plate 6 and having a throttle part, driving A radial oil hole 7b provided perpendicular to the oil hole 7a of the shaft 7 is communicated sequentially.
[0035]
  Further, the low stage vane back chamber 33 communicates with the low stage discharge chamber 27 via an oil supply passage 88 having an outlet 89 above the spring mounting hole 34.
[0036]
  The low-stage discharge chamber 27 communicates with the suction chamber of the high-stage compression element 4 through an intermediate communication passage 87 provided through the auxiliary bearing 11, the high-stage cylinder block 10, and the middle plate 6.
[0037]
  An electrical connection terminal 86 connected to the electric motor 2 is disposed on the flat portion at the center of the upper wall of the sealed container 1, and an external connection cluster 85 bound with an insulating resin material is inserted into the external connection terminal 86a. The inner shape of the terminal cover 84 surrounding the external connection cluster 85 is, for example, the case where the terminals constituting the electrical connection terminal 86 are partially removed by the high-pressure CO 2 gas pressure in the sealed container 1. Is set so as not to be disconnected from the external connection terminal 86a.
[0038]
  In the vicinity of the opening end on the motor chamber 29 side of the discharge pipe 83 disposed on the upper wall of the sealed container 1, a shielding plate 82 opened on the inner wall side of the sealed container 1 is disposed, and from the electric connection terminal 86 side. The direct gas outflow to the discharge pipe 83 is prevented.
[0039]
  The operation of the rolling piston type rotary two-stage compressor using the carbon dioxide (CO2) refrigerant gas configured as described above will be described with reference to FIGS. 1, 2, and 3.
[0040]
  The suction refrigerant gas taken into the cylinder of the low stage compression element 5 is compressed and then discharged into the low stage discharge chamber 27. The refrigerant gas discharged from the low-stage discharge chamber 27 is taken into the suction chamber of the high-stage compression element 4 via the intermediate communication passage 87, and is discharged to the high-stage discharge chamber 13 after being compressed and discharged to the motor chamber 9. The A part of the lubricating oil mixed in the refrigerant gas discharged into the electric motor chamber 9 is separated and collected in the oil reservoir 32. The high-pressure discharged refrigerant gas from which a part of the lubricating oil has been separated is sent to the compressor external piping system via the discharge pipe 83.
[0041]
  Lubricating oil in the oil reservoir 32 on which the refrigerant gas pressure discharged from the high-stage compression element 4 acts is supplied to the oil hole 7a and the radial oil hole 7b in the drive shaft 7 by centrifugal pump means 93 disposed at the lower end of the drive shaft 7. , The inner diameter side space of the low stage piston 70, the inner diameter side space of the high stage piston 65, and the bearing sliding surface of the main bearing 9 are sequentially discharged to the motor chamber 29 and returned to the oil reservoir 32 again.
[0042]
  The refrigerant gas mixed in the lubricating oil discharged from the centrifugal pump means 93 into the oil hole 7a in the drive shaft 7 is discharged from the upper opening end of the oil hole 7a to the electric motor chamber 29. As a result, the lubricating oil in the oil hole 7 a is degassed, so that the inner sliding surface of the low stage piston 70, the inner sliding surface of the high stage piston 65, and the bearing sliding surface of the main bearing 9 are filled with gas. No good oil film is formed.
[0043]
  Lubricating oil in the course of lubrication of the sliding portion of the drive shaft 7 is reduced to an intermediate pressure through an oil hole 68 having a throttle portion of the intermediate plate 6, and then the gap passage 90, the spring mounting hole 34, and the low step. The vane rear chamber 33, the outlet 89 above the spring mounting hole 34, and the intermediate communication passage 87 are sequentially supplied to the low-stage discharge chamber 27. Since the intermediate communication passage 87 is a passage that does not cause a throttling action, the low-stage vane back pressure chamber 33 has an equivalent pressure to the low-stage discharge chamber 27.
[0044]
  Since the outlet 89 of the intermediate communication path 88 that communicates the low-stage vane back pressure chamber 33 and the low-stage discharge chamber 27 is located above the spring mounting hole 34, the low-stage vane back pressure chamber 33 does not stop even when the compressor is stopped. Lubricating oil is provided to lubricate the sliding part gap of the low stage vane 92 at the initial stage of restart of the compressor without flowing out into the low stage discharge chamber 27 by its own weight.
[0045]
  As a matter of course, the lubricating oil in the low-stage vane back pressure chamber 33 is sufficiently ensured even during the operation of the compressor, and the oil film sealing action of the sliding portion gap of the low-stage vane 92 and the low-stage vane 92 are combined with the low-stage piston. To press.
[0046]
  This pressing force is halved compared to the case where the lubricating oil in the oil reservoir 32 is introduced into the low-stage vane back chamber 33 without being depressurized, and the outer circumferential surface of the low-stage piston 70 and the low-stage vane 92 The sliding friction loss with the tip is small, and the sliding part wear is small.
[0047]
  Further, the low-stage vane back chamber 33 is pressure-separated from the inside of the hermetic container 1 by a sealing member interposed between the high-stage cylinder block 8 and the low-stage discharge cover 26, for example, the oil level of the oil reservoir 32. Even when the pressure drops, the discharged refrigerant gas in the sealed container 1 does not leak into the low-stage vane back chamber 33. Further, the refrigerant gas discharged from the sealed container 1 and the lubricating oil on which the discharge pressure acts act via the contact coupling surface between the middle plate 6 and the high stage cylinder block 8 and the contact coupling surface between the middle plate 6 and the low stage cylinder block 10. Therefore, the leakage does not flow directly into the compression chamber of the high-stage compression element 4 and the compression chamber of the low-stage compression element 5.
[0048]
  An appropriate amount of lubricating oil introduced from the low-stage vane back chamber 33 into the suction chamber of the high-stage compression element 4 via the low-stage discharge chamber 27 is used to seal the oil film in the compression chamber gap of the high-stage compression element 4. , Improve the compression efficiency.
[0049]
  As described above, according to the above-described embodiment, the motor 2 and the compression mechanism connected to the motor 2 are housed in the sealed container 1, and the compressed gas of the compression mechanism 3a is discharged into the sealed container 1. The outer peripheral portion of the joint surface between the constituent members (the high-stage cylinder block 8 and the middle plate 6, the low-stage cylinder block 10 and the middle plate 6) forming the compression chamber of the compression mechanism 3a is pressure-blocked from the inside of the sealed container 1. Separating means (a state in which the low-stage discharge cover 26 surrounding the high-stage cylinder block 8, the middle plate 6, the low-stage cylinder block 10, and the auxiliary bearing 11 is attached to the high-stage cylinder block 8 via the seal member 98). This prevents high-pressure (equivalent to discharge pressure) fluid (discharge refrigerant gas or lubricating oil) in the sealed container 1 from leaking into the compression chamber via the contact coupling surfaces between the components forming the compression chamber. , Prevent compression efficiency It can be achieved.
[0050]
  Further, according to the above embodiment, the compression mechanism section 3a is composed of a plurality of compression elements (the low-stage compression element 5 and the high-stage compression element 4), and is arranged adjacent to each compression element to connect the respective compression elements. In addition, the low-stage discharge cover 26 is disposed in a form surrounding the outer peripheral portion of the middle plate 6 which is a member constituting the wall surface of the compression chamber and is blocked from the inside of the sealed container 1 by pressure, whereby the middle plate 6 and each compression element ( It is possible to prevent the high-pressure fluid (discharged refrigerant gas or lubricating oil) in the sealed container 1 from leaking and flowing into the compression chamber via the adjacent surfaces 4 and 5), thereby preventing the compression efficiency from being lowered.
[0051]
  Further, according to the above embodiment, since the compression element is the two-stage compression mechanism 3 in which the low-stage compression element 5 and the high-stage compression element 4 are sequentially connected in series, the discharged refrigerant gas and the lubricating oil in the sealed container 1 are contained in the middle. The leakage of the low-stage compression element 5 and the high-stage compression element 4 to the suction side of the compression chamber through the plate 6 is prevented, the occurrence of compression loss in the high-stage compression element 4 is prevented, and the low-stage compression element It is possible to prevent compression loss from being transferred from 5 to the high-stage compression element 4 and to prevent a significant reduction in compression efficiency.
[0052]
  Further, according to the above embodiment, by providing the isolating means for pressure-blocking the outer peripheral portion of the components of the low-stage compression element 5 from the inside of the sealed container 1, the discharged refrigerant gas and the lubricating oil in the sealed container 1 Prevention of excessive compression loss caused by leaking into the suction side (low pressure side) of the compression chamber of the low-stage compression element 5 via the intermediate plate 6 and re-compression of the leaked fluid in the high-stage compression element 4 again. Can be planned.
[0053]
  Further, according to the above embodiment, the separating means is fixed to the low-stage cylinder block 10 so as to support the low-stage cylinder block 10 and the drive shaft 7 of the low-stage compression element 5 and to form a compression chamber together with the low-stage cylinder block 10. The low-stage discharge cover 26 is provided with an annular portion so as to surround the outer peripheral portion of the intermediate plate 6 disposed adjacent to the low-stage cylinder block 10 so as to form a compression chamber together with the auxiliary bearing 11 and the low-stage cylinder block 10. Thus, the fluid (discharged refrigerant gas or lubricating oil) discharged into the hermetic container 1 passes through two contact fixing surfaces of the auxiliary bearing 11 and the low-stage cylinder block 10 and the middle plate 6 and the low-stage cylinder block 10. It is possible to prevent leakage and flow into the suction side of the compression chamber of the low-stage compression element 5 and prevent a significant reduction in compression efficiency.
[0054]
  Further, according to the above embodiment, the separating means is provided with means for pressure-blocking the joint surface between the middle plate 6 and the high-stage cylinder block 8 of the high-stage compression element 4 from the inside of the sealed container 1. The discharge fluid (discharge refrigerant gas and lubricating oil) in the container 1 is supplied to both compression chambers via contact fixing surfaces of components arranged to form both compression chambers of the low-stage compression element 5 and the high-stage compression element 4. It is possible to prevent leakage and inflow and prevent a reduction in compression efficiency.
[0055]
  Further, according to the above embodiment, the isolating means is a low stage formed so as to surround the outer periphery of the low stage 10 cylinder block of the low stage compression element 5 so as to form the low stage discharge chamber 27 of the low stage compression element 5. By serving also as the discharge cover 26, the low-stage discharge cover 26 attached after the low-stage compression element 5 is assembled has the outer peripheral portion of the low-stage cylinder block 10 in which the compression chamber is disposed inside the discharge refrigerant in the sealed container 1. By blocking from gas and lubricating oil, unnecessary leakage fluid inflow into the compression chamber can be avoided and compression efficiency can be improved.
[0056]
  In the above embodiment, the intermediate communication passage 87 of the intermediate plate 6 and the low-stage vane back chamber 33 communicate with each other via the gap passage 90, but they may communicate directly without the gap passage 90. good.
Then, a seal member is arranged on the outer peripheral portion of the contact coupling surface with the low-stage cylinder block 10 to completely isolate and seal the discharged refrigerant gas or lubricating oil in the hermetic container 1 and the compression chamber, and to the compression chamber. The compression efficiency can be improved by avoiding fluid leakage.
[0057]
  (Example 2)
  FIG. 4 shows a longitudinal section of a scroll compressor in which the sealed container 1 is filled with carbon dioxide (CO2) discharge refrigerant gas.
[0058]
  A fixed scroll 3034 is fastened to a main body frame 3002 that supports a drive shaft 3005 connected to an electric motor (motor) 3010. The orbiting scroll 3014 meshing with the fixed scroll 3034 is disposed in the back pressure chamber 3020 while being supported by the main body frame 3002, and is related to the eccentric shaft portion 3008 at the tip of the drive shaft 3005 and the rotation prevention mechanism locked to the main body frame 3002. Together, it turns. A compression space formed by meshing the fixed scroll 3034 and the orbiting scroll 3014 constitutes a suction chamber 3022 whose outer portion communicates with the suction pipe 3028, and its compression chamber communicates with the discharge port 3025. The back pressure chamber 3020 communicates with the suction chamber 3022 through a balance passage 3026 having a throttle function.
[0059]
  A discharge cover 3099 is attached to the end plate 3021 of the fixed scroll 3034 to form a discharge chamber 3024. The discharge cover 3099 is disposed so as to surround the outer periphery of the end plate 3021 and the main body frame 3002.
[0060]
  An O-ring 3098 is pressed between the fastening outer peripheral portion of the end plate 3021 of the fixed scroll 3034 and the main body frame 3002 and the discharge cover 3099, and the discharged refrigerant gas in the sealed container 1 is moved to the inner side of the main body frame 3002 ( Inflow into the back pressure chamber 3020) is prevented.
[0061]
  In such a configuration, the scroll compressor is operated with the suction chamber 3022 maintained at 3 MPa, the discharge chamber 3024 maintained at 10 MPa, and the back pressure chamber maintained at 5 MPa. The refrigerant gas in the sealed container 1 is prevented from leaking into the suction chamber 3022 via the back pressure chamber 3020 by the sealing function of the O-ring 3098. This prevents a reduction in compression efficiency and provides a highly efficient scroll compressor.
[0062]
  (Example 3)
  FIG. 6 is a plan view of the fixed scroll end plate 3021a and the main body frame 3002a provided with a protruding portion 3021b and a protruding portion 3002b on the outer periphery of the fastening surface. The fragmentary sectional view of the scroll compressor replaced with the sealing function of the O-ring 3098 is shown. Concentrated welding joining such as laser welding can weld and join the end plate 3021a and the main body frame 3002a without thermal deformation during welding. Further, electron beam welding is suitable for concentrated welding joining when the material of the end plate 3021a and the main body frame 3002a is aluminum alloy or the like.
[0063]
  In the above embodiment, the rolling piston type rotary two-stage compressor and scroll compressor using carbon dioxide refrigerant have been described. However, the second stage compresses other gas (for example, oxygen, nitrogen, helium, air, etc.). In the case of a rolling piston type rotary compressor and a scroll compressor, similar actions and effects are produced.
[0064]
【The invention's effect】
  As is apparent from the above embodiments, the invention according to claim 1 is configured such that an electric motor and a compression mechanism connected to the electric motor are housed in a sealed container, and compressed gas from the compression mechanism is discharged into the sealed container. InThe compression mechanism section is a two-stage compression mechanism in which the compression element is connected in series with a low-stage compression element and a high-stage compression element, and is arranged adjacent to each compression element so as to connect the compression elements. While isolating the outer peripheral portion of the intermediate plate, which is one member of the wall structure, from the inside of the sealed container by the isolation means,Isolation means for pressure-blocking the outer peripheral portion of the joint surface between the constituent members forming the compression chamber of the compression mechanism portion from the inside of the sealed containerThe separating means includes a low-stage cylinder block of a low-stage compression element, a bearing member that supports the drive shaft and is fixed to the low-stage cylinder block so as to form a compression chamber together with the low-stage cylinder block, and the low-stage cylinder In order to form the compression chamber together with the block, it is constituted by a member provided with an annular portion so as to surround the outer peripheral portion of the intermediate plate arranged adjacent to the low-stage cylinder block.It is a thing.
[0065]
  And according to this configuration, it is possible to prevent high-pressure (equivalent to discharge pressure) fluid (gas or lubricating oil) in the sealed container from leaking into the compression chamber via the coupling surface between the constituent members forming the compression chamber,Further, the fluid (gas or lubricating oil) discharged into the sealed container is a compression chamber of the low-stage compression element through two contact fixing surfaces of the bearing member and the low-stage cylinder block, and the middle plate and the low-stage cylinder block. Prevents leakage into the suction side of theA reduction in compression efficiency can be prevented.
[0066]
  Claim2The invention described in 1 is configured such that the motor and the compression mechanism connected to the motor are housed in the sealed container, and the compression chamber of the compression mechanism is formed in the structure in which the compressed gas of the compression mechanism is discharged into the sealed container. Isolating means for pressure-blocking the outer peripheral portion of the connecting surface between the members from the inside of the sealed container is provided, and the compression mechanism portion is composed of a plurality of compression elements, and is adjacent to each compression element to connect the respective compression elements. Two stages in which the outer peripheral part of the middle plate, which is a member constituting the wall surface of the compression chamber, is pressure-blocked from the inside of the sealed container by the isolation means, and the compression element is sequentially connected in series with the low-stage compression element and the high-stage compression element As a compression mechanism, there is provided isolation means for pressure-blocking the outer periphery of the components of the low-stage compression element from the inside of the sealed container, and the isolation means supports the low-stage cylinder block and the drive shaft of the low-stage compression element. And low stage cylinder block A bearing member fixed to the low-stage cylinder block to form a compression chamber together, and an annular portion to surround the outer periphery of the intermediate plate disposed adjacent to the low-stage cylinder block to form a compression chamber together with the low-stage cylinder block The isolation means is provided with means for pressure-blocking the joint surface between the middle plate and the high-stage cylinder block of the high-stage compression element from the inside of the sealed container. According to this configuration, the discharged fluid (gas or lubricating oil) in the hermetic container is both connected via the contact fixing surfaces of the constituent members arranged to form both the compression chambers of the low-stage compression element and the high-stage compression element. It is possible to prevent leakage from flowing into the compression chamber and prevent a reduction in compression efficiency.
[0067]
  Claim3The invention described in 1 is configured such that the motor and the compression mechanism connected to the motor are housed in the sealed container, and the compression chamber of the compression mechanism is formed in the structure in which the compressed gas of the compression mechanism is discharged into the sealed container. Isolating means for pressure-blocking the outer peripheral portion of the coupling surface between the members from the inside of the sealed container is provided, and the compression mechanism portion is composed of a plurality of compression elements, and is adjacent to each compression element to connect the respective compression elements. Two stages in which the outer peripheral part of the middle plate, which is a member constituting the wall surface of the compression chamber, is pressure-blocked from the inside of the sealed container by the isolation means, and the compression element is sequentially connected in series with the low-stage compression element and the high-stage compression element An isolating means is provided as a compression mechanism for pressure-blocking the outer peripheral portion of the component of the low-stage compression element from the inside of the sealed container, and the isolation means is a low-stage to form a low-stage discharge chamber of the low-stage compression element. Outside the lower cylinder block of the compression element Parts in which also serves as the formed discharge cover to surround the. According to this configuration, the discharge cover is attached after the low-stage compression element is assembled, and the outer periphery of the low-stage cylinder block in which the compression chamber is disposed is shielded from the discharge fluid atmosphere in the sealed container. Can be easily assembled and unnecessary leakage fluid inflow into the compression chamber can be avoided, and compression efficiency can be improved.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a rolling piston type rotary two-stage compressor showing a first embodiment of the present invention.
FIG. 2 is a partial sectional view of a compression mechanism section in the compressor.
Fig. 3 External view of high-stage cylinder block in the same compressor
FIG. 4 is a longitudinal sectional view of a scroll compressor showing a second embodiment of the present invention.
FIG. 5 is a partial sectional view showing a seal portion in the compressor.
FIG. 6 is a partial sectional view showing a seal portion of a scroll compressor according to a third embodiment of the present invention.
FIG. 7 is a connection diagram of a conventional rolling piston type rotary two-stage compressor and a refrigeration cycle piping system.
FIG. 8 is a longitudinal sectional view of the compressor.
FIG. 9 is a partial longitudinal sectional view of the compressor.
FIG. 10 is a longitudinal sectional view of a conventional scroll compressor
[Explanation of symbols]
  1 Airtight container
  2 Electric motor
  3 Two-stage compression mechanism
  3a Compression mechanism
  4 High-stage compression element
  5 Low stage compression element
  6 Middle plate
  7 Drive shaft
  8 High cylinder block
  10 Low stage cylinder block
  26 Low-stage discharge cover
  27 Low discharge chamber
  3001 Airtight container
  3002 Body frame
  3002a Protruding part
  3003 Main bearing
  3013 Slewing bearing
  3014 Orbiting scroll
  3014a Orbiting scroll wrap
  3014b Wrap support disk
  3021 End plate
  3021b Protruding part
  3022 Suction chamber
  3024 Discharge chamber
  3025 Discharge port
  3034 fixed scroll
  3034a Fixed scroll wrap
  3097 scroll compression mechanism
  3098 Sealing member (O-ring)
  3099 Discharge cover

Claims

In a configuration in which an electric motor and a compression mechanism connected to the electric motor are housed in a sealed container, and the compressed gas of the compression mechanism is discharged into the sealed container, between the constituent members forming the compression chamber of the compression mechanism A rotary gas compressor provided with an isolating means for pressure-blocking the outer peripheral portion of the coupling surface from the inside of the sealed container , wherein the compression mechanism section sequentially converts the compression element into a low-stage compression element and a high-stage compression element. A two-stage compression mechanism connected in series is provided, and the outer peripheral portion of the intermediate plate, which is disposed adjacent to each compression element and is a member of the wall surface configuration of the compression chamber, is connected by the isolation means to connect the compression elements. Isolating means for pressure-blocking from the inside and pressure-blocking the outer peripheral portion of the components of the low-stage compression element from the inside of the sealed container is provided, and the isolation means includes a low-stage cylinder block of the low-stage compression element, Supports the drive shaft and A bearing member fixed to the low-stage cylinder block to form a compression chamber together with the low-stage cylinder block, and a middle plate disposed adjacent to the low-stage cylinder block to form the compression chamber together with the low-stage cylinder block. A rotary gas compressor comprising a member having an annular portion so as to surround an outer peripheral portion .

2. The rotary gas compressor according to claim 1, wherein the isolating means is configured to pressure-block a joint surface between the intermediate plate and the high-stage cylinder block of the high-stage compression element from the inside of the sealed container .

The isolation means is configured to serve also as a discharge cover formed so as to surround an outer peripheral portion of a low-stage cylinder block of the low-stage compression element so as to form a low-stage discharge chamber of the low-stage compression element. rotary gas compressor according to.