JP4208239B2

JP4208239B2 - Positive displacement machine

Info

Publication number: JP4208239B2
Application number: JP2003200831A
Authority: JP
Inventors: 功早瀬; 弘勝香曽我部; 和広遠藤; 健司東條; 健一大島
Original assignee: Hitachi Appliances Inc
Current assignee: Hitachi Global Life Solutions Inc
Priority date: 2003-07-24
Filing date: 2003-07-24
Publication date: 2009-01-14
Anticipated expiration: 2023-07-24
Also published as: JP2005042568A

Description

【０００１】
【発明の属する技術分野】
本発明は、容積形機械、および、該容積形機械を用いた冷凍空調機器などの効率と信頼性向上技術に関する。
【０００２】
【従来の技術】
従来のレシプロ式容積形機械における吸入行程は、特開平９−７２２７５号公報（特許文献1）の図７に記載の圧縮機のように作動室の容積が最大となった後に吸入弁が差圧により閉じることにより終了する構成であるか、特許文献1の図４に記載の４サイクルエンジンのように比較的複雑なカム機構により駆動される動弁機構の吸入弁が閉じることにより終了する構成であった。
【０００３】
また、従来のレシプロ式容積形機械では、特許文献１の図４に記載の４サイクルエンジンのような機構であるため、ピストンとクランク軸を連接させる連接棒から作用する力により、ピストン外周とその往復動を案内するシリンダ内周との間に摺動荷重が作用する構造であった。
【０００４】
【特許文献１】
特開平９−７２２７５号公報（図４、図７）
【０００５】
【発明が解決しようとする課題】
レシプロ式容積形機械を例えば膨張機として機能させるためには、高圧のガスを作動室の容積増大期間の途中まで吸入し、その後密閉された作動室のなかで最大容積まで膨張させて動力を取出すことが必要であるが、特許文献１の吸入弁では、作動室の容積増大期間の途中で作動室を吸入経路から遮断することができないか複雑な動弁機構を必要とするという問題があった。
【０００６】
本発明の第１の目的は、弁機構が安価に構成できるレシプロ式容積形機械、とりわけ、容積形膨張機を構成することである。
【０００７】
また、レシプロ式容積形機械におけるピストンとシリンダ間の摺動荷重は、摩擦損失と摺動部の損傷の原因となり、効率と信頼性の低下要因となっている。
【０００８】
本発明の第２の目的は、上記の摩擦損失と摺動部損傷を回避し高効率で高信頼性のレシプロ式容積形機械を構成することである。
【０００９】
更に、容積形機械を用いて膨張機を構成して冷凍サイクルにおける従来の絞り機構（膨張弁等）の代りとした場合、上記の膨張機の作動室内部には膨張前あるいは膨張後の段階で液冷媒が存在するため作動室内部の摺動面に供給された潤滑油が洗浄され、良好な潤滑状態が期待できない懸念がある。その際、上記従来技術のレシプロ式容積形機械を用いた膨張機では作動室の周囲のピストン外周とそのシリンダ内周との間に押付力が作用するため、信頼性の確保が困難となる。
【００１０】
本発明の第３の目的は、高圧の作動流体から動力を回収して高いシステム効率を実現するための膨張機を組込み込んだ冷凍空調システムの信頼性を確保することである。
【００１１】
【課題を解決するための手段】
第１の目的を達成するために、往復動部材が往復運動に伴って該往復運動方向の軸線回りの揺動運動を行うレシプロ式容積形機械において、バルブ機構のための可動部品を用いずに、往復動部材の前記運動を利用して作動空間をその容積の増減に応じて吸入室空間あるいは吐出室空間と交互に連通させるための連通経路を構成したものである。
また、第２の目的を達成するためには、ピストン頭部に作用する荷重によるピストン外周とシリンダ内周との間の押付力の発生を回避すると同時に、作動空間と吸入室空間あるいは吐出室空間とを連通させるための連通経路をそれぞれシリンダ内周の対向した位置に対となるように設けることにより吸入・吐出の連通経路の圧力がピストン側面に作用することによるシリンダ内周との間の押付力の発生を回避したものである。
さらに、第３の目的を達成するためには、往復運動部材の両端のピストン部に形成した２つの作動室の一方を圧縮機部分、他方を上記構成の膨張機部分として構成し、圧縮機部分で動力を供給して高圧にした作動流体の少なくとも一部を膨張機部分に導いて動力を回収しながら減圧する容積形機械を構成し、これを用いて冷凍空調機器などのシステム事例においては冷凍サイクルの圧縮行程と膨張行程とを行なわせるようにしたものである。
【００１２】
【発明の実施の形態】
以下、本発明の実施例を図１ないし図１０により説明する。図１は本発明の第1の実施例である冷媒を作動流体とした膨張・圧縮機の全体の側断面図である。図２、図３はそれぞれ図１におけるＢ−Ｂ断面図、Ｃ−Ｃ断面図である。図４は図１におけるＡ−Ａ断面図であり、図５、図６はそれぞれ図４におけるＤ−Ｄ断面図、Ｅ−Ｅ断面図である。図７は本発明の第１の実施例である膨張・圧縮機を冷凍・空調機器に適用した場合の冷凍サイクル構成図である。図８は本発明の第２の実施例であるポンプの軸直角方向の断面図であり、図９、図１０はそれぞれ図８におけるＦ−Ｆ断面図、Ｇ−Ｇ断面図である
図１ないし図６に本発明の第1の実施例である冷媒を作動流体とした膨張・圧縮機を示す。往復動部材１はその２つのピストン頭部１ａ、１ｂをそれぞれシリンダブロック２の２つの内周円筒面２ａ、２ｂにより案内されて往復運動と該往復運動方向軸線の回りの回転を行なえる様に支持されている。往復動部材１のピストン頭部１ａ、１ｂはその往復運動方向と直角方向で互いに反対側に突出した２つの円筒状のアーム部１ｃに挿入されてピン１ｄにより固定されている。前記２つのアーム部１ｃはそれぞれ球面ブッシュ３の内周円筒面に回転自在に挿入されている。２つの球面ブッシュ３の外周球面部は、それぞれ駆動軸４の駆動アーム部４ａにより駆動軸４の回転軸から半径方向に偏位した位置で球面対偶により支持されている。
【００１３】
その結果、往復動部材の２つのアーム部１ｃと２つの駆動軸４とは相対的な回転と互いの相対的な傾斜方向変化が可能の状態で、駆動軸４の回転軸から偏位した位置で連結されている。駆動軸４の駆動アーム部４ａの径方向反対側には釣合い質量４ｂが形成されている。また２つの駆動軸４はそれぞれ軸受フレーム５の軸受部５ａにより回転支持されている。２つの軸受フレーム５はそれらの軸受部５ａの中心軸が互いに同軸上に配置される様にそれぞれシリンダブロック２にボルトにより固定されている。シリンダブロック２に形成された２つの内周円筒面２ａ、２ｂの中心軸同士はやはり互いに同軸であり、更に、そのシリンダブロック２に固定された軸受フレーム５の軸受部中心軸とは、互いに直角になっている。
【００１４】
シリンダブロック２に形成された一方の内周円筒面２ａの開口端はボルトで固定されたシリンダヘッド６により閉塞されており、往復動部材のピストン頭部１ａとシリンダブロックの内周円筒面２ａとシリンダヘッド６とにより囲まれた作動室７が形成されている。往復動部材のピストン頭部１ａには作動室７への連絡通路１ｅ、１ｆ、１ｇが形成されている。連絡通路１ｅ、１ｆはそれぞれピストンを貫通してピストン側面の円筒面にそれぞれ２つの開口部を有し、互いには９０度方向が異なりピストン中心部で交差している。図１に図示されている連絡通路１eが吐出通路であり、図４に図示されている連絡通路１fが吸入通路である。連絡通路１ｇは前記１ｅ、１ｆの交差部と作動室７とを連通させている。シリンダブロック２にはそれぞれ内周円筒面２ａに開口する膨張機部吐出ポート２ｃおよび膨張機部吸入ポート２ｄが２つずつ形成されている。図１に図示されている２つの膨張機部吐出ポート２ｃは右側の一方が破線で示され左側のもう一方が一点鎖線で示されており、それぞれ断面（紙面）に対して前方および手前で内周円筒面２ａに開口しているが、互いにはほぼ１８０度対向した位置に開口している。膨張機部吐出ポート２ｃの内周円筒面２ａと反対側の２つの開口部をシリンダブロック２にボルト等（図示せず）により固定された２つのカバー８が閉塞しており、カバー８には膨張機部吐出配管９が連結されている。
【００１５】
図４に図示されている２つの膨張機部吸入ポート２ｄは右側の一方が一点鎖線で示され左側のもう一方が破線で示されており、それぞれ断面（紙面）に対して手前および前方で内周円筒面２ａに開口しているが、互いにはほぼ１８０度対向した位置に開口している。膨張機部吸入ポート２ｄの内周円筒面２ａと反対側の２つの開口部をシリンダブロック２にボルト等（図示せず）により固定された２つのカバー１０が閉塞しており、カバー１０には膨張機部吸入配管１１が連結されている。
【００１６】
一方上部には、往復動部材１のピストン頭部１ｂとシリンダブロック２の内周円筒面２ｂとシリンダヘッド１２とにより囲まれた作動室１３が形成されている。このピストン頭部１ｂには圧縮機部吸入ポート１ｈが形成され、更に、吸入バルブプレート１４がリベット１５により装着されている。リベット１５は吸入バルブプレート１４がピストン頭部１ｂの上端面から浮き上がれるように拘束しており、吸入行程において吸入ポート１ｈから作動室１３への冷媒ガスの流入を可能にしている。シリンダブロック２には圧縮機部吸入配管１６が連結されており、本第１の実施例の膨張・圧縮機内部はピストン頭部１ｂの背面に至るまで圧縮機の吸入圧力となって、前記の吸入ポート１ｈと圧縮機部吸入配管１６とが連絡されている。シリンダヘッド１２には圧縮機部吐出ポート１２ａが形成されており、吐出バルブプレート１７と吐出バルブ押え１８がボルト（図示せず）により固定されている。シリンダヘッド１２は、吐出空間１９を取囲む吐出室カバー２０と共にボルトによりシリンダブロック２に固定されている。吐出室カバー２０には圧縮機部吐出配管２１が連結されている。
【００１７】
２つの軸受フレーム５には、それぞれ駆動用モータ２２のステータ部２２ａがボルトで固定され、２つの駆動軸４にはそれぞれ軸受部５ａを挟んで駆動アーム部４ａの反対側に駆動用モータ２２のロータ部２２ｂが固定されている。ロータ部２２ｂには前述の釣合い質量４ｂと逆方向でより小さな遠心力を発生する釣合い質量２３が取付けられている。ステータ部２２ａとロータ部２２ｂとで構成される２組の駆動用モータ２２は同じものであるが、上記の膨張・圧縮機の全体構成中に互いに対向した姿勢で組込まれており、２つの駆動軸４を互いに逆方向に回転駆動する。本第１の実施例では、図１における右側の駆動用モータ２２と左側の駆動用モータ２２がそれぞれ図の右方向より観て時計方向、反時計方向に回転駆動する構成になっている。なお、２つの軸受フレーム５にはシリンダブロック２への固定ボルトによる共締めでモータカバー２４が固定されている。
【００１８】
以上の構成において２つの駆動軸４が互いに逆方向に回転駆動すると、駆動軸４の回転軸から半径方向に偏位した位置にある２つの球面ブッシュ３の球中心が図１の上下方向には同位相で往復運動し、図１の紙面垂直方向には互いに逆位相で往復運動するため、球面ブッシュ３により２つの円筒状のアーム部１ｃを支持された往復動部材１は、特許文献１（図８）にも示す様に図の上下方向に往復運動を行ないながらその往復運動方向軸線の回りの揺動を繰り返す。この時、往復動部材１のピストン頭部１ａに形成された連絡通路１ｅ、１ｆのそれぞれ２つずつのピストン側面開口部は、球面ブッシュ３の中心と駆動軸４の回転軸との偏位量に対して倍のストロークで上下方向に往復運動行なうが、揺動方向にはほぼピストン外径を２つの球面ブッシュ３の中心間距離で割った比率で揺動運動のストロークが縮小される。すなわち、それぞれ図２、図３、図５、図６に示される楕円軌跡２５を描く運動を行なう。
【００１９】
図２、図３および図４、図５には、それぞれの断面内に膨張機部吐出ポート２ｃおよび膨張機部吸入ポート２ｄの位置が記載されており、それらに対向した位置にあるピストン頭部１ａの連絡通路１ｅ、１ｆの前記開口部位置を破線にて示し、その運動の楕円軌跡２５を一点鎖線にて示してある。更に、前記の方向に各駆動軸４が回転する時の連絡通路１ｅ、１ｆ開口部の運動方向を矢印にて示す。
【００２０】
シリンダブロック２にはそれぞれ内周円筒面２ａに開口する膨張機部吐出ポート２ｃおよび膨張機部吸入ポート２ｄが２個ずつ形成されているが、膨張機部吸入ポート２ｄは膨張機部吐出ポート２ｃに比べて小さい。また、カバー１０に連結された膨張機部吸入配管１１を介して高圧の作動流体を供給し膨張機部吸入ポート２ｄを高圧の作動流体空間とし、膨張機部吐出ポート２ｃを低圧の作動流体空間としてカバー８に連結された膨張機部吐出配管９より減圧された作動流体を排出する構成である。
【００２１】
以上の構成により、作動室７はその容積が増大する吸入行程の初期期間のみピストン頭部１ａの連絡通路１ｆを介して膨張機部吸入ポート２ｄと導通して高圧の作動流体を吸入し、吸入行程の後期期間では吸入・吐出の両ポートと遮断された密閉空間となって容積を増大させ内部の作動流体を膨張させる。膨張機部吐出ポート２ｃは十分大きく、作動室７はその容積が減少する吐出行程の全期間でピストン頭部１ａの連絡通路１ｅを介して膨張機部吐出ポート２ｃと導通し、膨張して低圧となった作動流体を吐出する。これらの吸入経路と吐出経路には可動部品や複雑な弁機構がなく安価な構成である。
【００２２】
これに対して、上部の作動室１３は往復動部材１の往復運動に伴う容積の周期的な変化によって、圧縮機部吸入ポート１ｈから吸入した冷媒ガスを圧縮した後に圧縮機部吐出ポート１２ａから吐出する。すなわち、下部の作動室７は膨張機として機能し、上部の作動室１３は圧縮機として機能する。
【００２３】
上記構造の本第1の実施例では特に以下に説明する特長を有する。本第1の実施例では、吸入経路である膨張機部吸入ポート２ｄと連絡通路１ｆ、吐出経路である連絡通路１ｅと膨張機部吐出ポート２ｃをいずれも２個ずつ有しており、それはそれぞれシリンダブロックの内周円筒面２ａの略１８０度対向した位置に対になって開口している。往復動部材のピストン頭部１ａ側面の上記各ポート開口部に対応した部分にはそれぞれ吸入圧力や吐出圧力が作用してピストン頭部１ａを反対側に押し付けようとするが、反対側のほぼ同じ面積と圧力の開口部からの同じ力で打ち消される。したがって、側面部の圧力によりピストン頭部１ａをシリンダの内周円筒面２ａに押付ける力は発生しない。
【００２４】
また、本実施例１は特許文献１の記載の機構を用いており、ピストン頭部１ａ、１ｂの端面の作動室圧力による軸方向の荷重は、その荷重作用線（ピストン中心軸）方向から見た荷重点に対して点対称の位置にある２つの球面ブッシュ３により安定して支持される。したがって、本実施例ではピストン端面部の圧力によってもピストン頭部１ａ、１ｂをシリンダの内周円筒面２ａ，２ｂに押付ける力は発生しない。つまり、本実施例１によればピストンとシリンダとの間の摺動荷重が極めて小さく摩擦損失の小さいレシプロ式容積形機械を提供できるという効果がある。
【００２５】
なお、本実施例１によれば、特許文献１にも記載してある通り、その採用している機構の基本的な特徴として振動の原因となる加振力がほとんど発生しないという効果もある。
【００２６】
図７に本発明の第１の実施例である膨張・圧縮機を冷凍・空調機器の冷凍サイクルに組込んだ場合のサイクル構成図を示す。中央の膨張・圧縮機２６は図１の第１の実施例である膨張・圧縮機である。図中の太線はサイクル配管２７であり太線上の矢印が内部の冷媒の流れ方向を示す。一般的な冷媒および運転条件下では、膨張・圧縮機２６の圧縮機部分で加圧されて高温高圧になった冷媒ガスは圧縮機部吐出配管２１より吐出され、サイクル配管２７を経て凝縮器２８に至りそこで放熱して凝縮し高圧の液冷媒となる。高圧の液冷媒の一部は次にサイクル配管２７を経ての2つの膨張機部吸入配管１１（図７中には図示せず。図４を参照）より膨張・圧縮機２６の膨張機部分に流入し、そこで減圧されながら一部がガス化して全体の容積を増大させ低圧の気液２相状態で２つの膨張機部吐出配管９より流出する。冷媒が２酸化炭素であり吐出圧が超臨界に達する場合は、上記の膨張機部分に流入する際の冷媒は液の状態でないが、いずれにしても膨張後は低圧の気液２相状態となって２つの膨張機部吐出配管９より流出する。その後、サイクル配管２７を経て蒸発器２９に至る。凝縮器２８から出た高圧冷媒の他の一部は、上記の膨張機を経由する経路とは並列に設けたサイクル配管経路を経由する構成となっているが、その経路に設けられた他の膨張手段３０により減圧されて低圧の気液２相状態でサイクル配管２７を経て蒸発器２９に至る。なお、膨張手段３０は、従来の冷凍サイクルにおける膨張弁やキャピラリーチューブなどと同様に絞りによるものであり、その絞り量を変えることにより冷凍サイクル全体の運転圧力や冷媒流量を制御するものである。
【００２７】
このシステム構成では、従来技術において凝縮器から出た高圧液冷媒の全量が膨張手段３０のような絞りを通過する際の圧力損失によって低下していた冷凍能力を膨張機で回収した動力分だけ回復させ、同量の消費動力を低減できるが、本発明第一の実施例の膨張・圧縮機２６を用いることで、更に下記の効果が発生する。このシステムでは前記の通り膨張・圧縮機２６の膨張機部分で減圧された冷媒は気液２相状態となって膨張機部吐出配管９より流出する。このため、膨張機部分の作動室１３内部では液冷媒によって表面に付着した潤滑油が洗われてしまう懸念がある。このため、膨張・圧縮機２６の全体あるいは冷凍・空調システム全体の信頼性を確保するには、作動室１３の内部表面の中でシリンダの内周円筒面２ａのように他の部品（ピストン頭部１ａ）と摺動を行なう表面の潤滑油が液冷媒で洗浄された際の摺動部の損傷を防止する対策が必要がある。本発明第一の実施例では上記摺動部に荷重をほとんど作用させないことによって摺動部の損傷を防止し信頼性の確保を可能にできるという効果がある。
【００２８】
図８ないし図１０に本発明の第２の実施例であるポンプを示す。本第の２の実施例の側断面は図１の下半分の膨張機部分の側断面と同じである。また、本第の２の実施例では、往復動部材３１の両端の２つピストン頭部３１ａ（一方は図示せず）は同一形状であり、その周囲に全く同じ作動室、吸入経路、吐出経路を持つものとする。以下、第１の実施例の膨張機部分と異なる部分について説明する。
【００２９】
図８に示されたシリンダブロック３２の２つの吸入ポート３２ｃは吐出ポート３２ｂ（図示せず、図１における吐出ポート２ｃと同一）と同様に往復動部材３１の往復動方向に長く、作動室３３の容積が増大している期間の全域で連絡通路３１ｅ、３１ｆを介して作動室３３と連通する。吐出ポート３２ｂも作動室３３の容積が減少している期間の全域で連絡通路３１ｄ、３１ｆ（ともに図示せず。図１における連絡通路１ｅ、１ｇと同一）を介して作動室３３と連通する。したがって、本第２の実施例は非圧縮性の液体を吸入して吐出するポンプとして機能する。本第の２の実施例では、吸入・吐出経路に可動部品や複雑な弁機構が無く安価な構成である点や、ピストンとシリンダ間に摺動荷重が発生しない点で第１の実施例と同様な効果が得られる。
【００３０】
なお、本発明の第１の実施例（図１〜図６）における下部の膨張機部分については、左右のモータ２２をそれぞれ逆方向に駆動すると、図２、図３、図５、図６における各連絡通路１ｅ、１ｆの開口部は楕円軌跡２５上を逆方向に移動し、吸入経路と吐出経路が入れ替わった状態で圧縮機として機能する。
【００３１】
更に本発明の第２の実施例（図８〜図１０）のポンプ部分については、吸入経路に高圧の油を導入し、吐出経路を減圧されて低圧となった油と連絡させると、２つの駆動軸４が出力軸となる油圧モータとして機能させることができる。
【００３２】
以上のとおり、各実施例の説明によって本発明によれば、バルブ機構のための可動部品を不要にでき、生産性が良く信頼性が高いレシプロ式容積形機械を提供できる。
【００３３】
また、本発明によれば、ピストンとシリンダ間の摺動荷重を大幅に低減し、機械摩擦損失と摺動部損傷のポテンシャルを低減できるので、高効率で高信頼性のレシプロ式容積形機械を提供できるという効果がある。
【００３４】
更に、本発明によれば、ピストンとシリンダ間の摺動荷重を大幅に低減することにより、膨張行程で気液２相状態となった冷媒により作動室内の潤滑状態が悪化しても摩耗・焼付きを防止できるので、膨張機による動力回収を行なう冷凍サイクルシステムの信頼性を向上できるという効果がある。
【００３５】
【発明の効果】
生産性、効率、信頼性を向上させたレシプロ式容積形機械を用い、これによって、冷凍サイクルにおいて膨張機により動力を回収する高効率なシステムの実用性を高めることができる。
【図面の簡単な説明】
【図１】本発明の第1の実施例である膨張・圧縮機の全体の側断面図。
【図２】図１におけるＢ−Ｂ断面図。
【図３】図１におけるＣ−Ｃ断面図。
【図４】図１におけるＡ−Ａ断面図。
【図５】図４におけるＤ−Ｄ断面図。
【図６】図４におけるＥ−Ｅ断面図。
【図７】本発明の第１の実施例である膨張・圧縮機を冷凍・空調機器に適用した場合の冷凍サイクル構成図。
【図８】本発明の第２の実施例であるポンプの軸直角方向の断面図。
【図９】図８におけるＦ−Ｆ断面図。
【図１０】図８における、Ｇ−Ｇ断面図。
【符号の説明】
１…往復動部材、１ａ…ピストン頭部、１ｂ…ピストン頭部、１ｃ…アーム部、１ｄ…ピン、１ｅ…連絡通路、１ｆ…連絡通路、１ｇ…連絡通路、１ｈ…圧縮機部吸入ポート、２…シリンダブロック、２ａ…内周円筒面、２ｂ…内周円筒面、２ｃ…膨張機部吐出ポート、２ｄ…膨張機部吸入ポート、３…球面ブッシュ、４…駆動軸、４ａ…駆動アーム部、４ｂ…釣合い質量、５…軸受フレーム、５ａ…軸受部、６…シリンダヘッド、７…作動室、８…カバー、９…膨張機部吐出配管、１０…カバー、１１…膨張機部吸入配管、１２…シリンダヘッド、１２ａ…圧縮機部吐出ポート、１３…作動室、１４…吸入バルブプレート、１５…リベット、１６…圧縮機部吸入配管、１７…吐出バルブプレート、１８…吐出バルブ押え、１９…吐出空間、２０…吐出室カバー、２１…圧縮機部吐出配管、２２…駆動用モータ、２２ａ…ステータ部、２２ｂ…ロータ部、２３…釣合い質量、２４…モータカバー、２５…楕円軌跡、２６…膨張・圧縮機、２７…サイクル配管、２８…凝縮器、２９…蒸発器、３０…膨張手段、３１…往復動部材、３１ａ…ピストン頭部、３１ｂ…アーム部、３１ｃ…ピン、３１ｄ…連絡通路、３１ｅ…連絡通路、３１ｆ…連絡通路、３１ｇ…連絡通路、３２…シリンダブロック、３２ａ…内周円筒面、３２ｂ…ポンプ吐出ポート３２ｃ…ポンプ吸入ポート、３３…作動室、３４…カバー、３５…ポンプ吸入配管。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a positive displacement machine and a technology for improving the efficiency and reliability of a refrigerating and air-conditioning apparatus using the positive displacement machine.
[0002]
[Prior art]
The suction stroke in the conventional reciprocating positive displacement machine is such that the suction valve has a differential pressure after the working chamber has a maximum volume as in the compressor shown in FIG. 7 of Japanese Patent Laid-Open No. 9-72275 (Patent Document 1). Or a configuration that ends when the intake valve of the valve mechanism that is driven by a relatively complicated cam mechanism, such as the four-cycle engine described in FIG. 4 of Patent Document 1, is closed. there were.
[0003]
Further, since the conventional reciprocating positive displacement machine is a mechanism like the four-cycle engine shown in FIG. 4 of Patent Document 1, the piston outer periphery and its force are applied by the force acting from the connecting rod that connects the piston and the crankshaft. The sliding load acts between the inner periphery of the cylinder that guides the reciprocating motion.
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 9-72275 (FIGS. 4 and 7)
[0005]
[Problems to be solved by the invention]
In order for a reciprocating positive displacement machine to function as an expander, for example, high-pressure gas is sucked in the middle of the volume increase period of the working chamber, and then expanded to the maximum volume in the sealed working chamber to extract power. However, the suction valve of Patent Document 1 has a problem that the working chamber cannot be shut off from the suction path in the middle of the volume increase period of the working chamber or a complicated valve mechanism is required. .
[0006]
A first object of the present invention is to construct a reciprocating positive displacement machine, in particular, a positive displacement expander, in which a valve mechanism can be constructed at low cost.
[0007]
In addition, the sliding load between the piston and the cylinder in the reciprocating positive displacement machine causes friction loss and damage to the sliding portion, which causes a reduction in efficiency and reliability.
[0008]
A second object of the present invention is to constitute a reciprocating positive displacement machine that avoids the above-mentioned friction loss and sliding part damage and has high efficiency and high reliability.
[0009]
Furthermore, when the expander is configured using a positive displacement machine and is used instead of the conventional throttle mechanism (expansion valve, etc.) in the refrigeration cycle, the inside of the working chamber of the expander is in a stage before or after expansion. Since liquid refrigerant exists, the lubricating oil supplied to the sliding surface inside the working chamber is washed, and there is a concern that a good lubricating state cannot be expected. At that time, in the expander using the above-described conventional reciprocating positive displacement machine, a pressing force acts between the outer periphery of the piston around the working chamber and the inner periphery of the cylinder, making it difficult to ensure reliability.
[0010]
A third object of the present invention is to ensure the reliability of a refrigeration air conditioning system incorporating an expander for recovering power from a high-pressure working fluid to achieve high system efficiency.
[0011]
[Means for Solving the Problems]
In order to achieve the first object, in a reciprocating positive displacement machine in which a reciprocating member swings around an axis in the reciprocating direction as the reciprocating member moves, without using a movable part for a valve mechanism. The communication path for alternately communicating the working space with the suction chamber space or the discharge chamber space according to the increase / decrease of the volume by using the motion of the reciprocating member is configured.
In order to achieve the second object, the generation of pressing force between the piston outer periphery and the cylinder inner periphery due to the load acting on the piston head is avoided, and at the same time, the working space and the suction chamber space or the discharge chamber space are avoided. By providing a communication path to communicate with each other at opposite positions on the cylinder inner circumference, the pressure between the suction and discharge communication paths acts on the side surface of the piston, and pressing between the cylinder inner circumference It avoids the generation of force.
Further, in order to achieve the third object, one of the two working chambers formed in the piston portions at both ends of the reciprocating member is configured as a compressor portion, and the other is configured as an expander portion having the above-described configuration. A positive displacement machine that reduces the pressure while recovering power by supplying at least a part of the working fluid that has been supplied with power to a high pressure to the expander part is used for refrigeration and air conditioning equipment. The compression stroke and the expansion stroke of the cycle are performed.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to FIGS. FIG. 1 is a side sectional view of an entire expansion / compression machine using a refrigerant as a working fluid according to a first embodiment of the present invention. 2 and 3 are a BB sectional view and a CC sectional view, respectively, in FIG. 4 is an AA cross-sectional view in FIG. 1, and FIGS. 5 and 6 are a DD cross-sectional view and an EE cross-sectional view in FIG. 4, respectively. FIG. 7 is a configuration diagram of a refrigeration cycle when the expansion / compressor according to the first embodiment of the present invention is applied to a refrigeration / air-conditioning apparatus. 8 is a cross-sectional view in the direction perpendicular to the axis of a pump according to a second embodiment of the present invention. FIGS. 9 and 10 are cross-sectional views taken along the lines FF and GG in FIG. FIG. 6 shows an expansion / compression machine using a refrigerant as a working fluid according to the first embodiment of the present invention. The reciprocating member 1 has its two piston heads 1a and 1b guided by the two inner cylindrical surfaces 2a and 2b of the cylinder block 2, respectively, so that it can reciprocate and rotate around the reciprocating direction axis. It is supported. Piston heads 1a and 1b of the reciprocating member 1 are inserted into two cylindrical arm portions 1c protruding in opposite directions perpendicular to the reciprocating direction and fixed by pins 1d. The two arm portions 1c are rotatably inserted into the inner peripheral cylindrical surface of the spherical bush 3. The outer spherical surface portions of the two spherical bushes 3 are supported by spherical pairs at positions displaced in the radial direction from the rotation axis of the drive shaft 4 by the drive arm portions 4a of the drive shaft 4, respectively.
[0013]
As a result, the two arm portions 1c of the reciprocating member and the two drive shafts 4 are displaced from the rotation axis of the drive shaft 4 in a state in which the relative rotation and the relative tilt direction change are possible. It is connected with. On the opposite side in the radial direction of the drive arm portion 4a of the drive shaft 4, a balance mass 4b is formed. The two drive shafts 4 are rotatably supported by bearing portions 5a of the bearing frame 5, respectively. The two bearing frames 5 are fixed to the cylinder block 2 with bolts so that the central axes of the bearing portions 5a are arranged coaxially with each other. The central axes of the two inner peripheral cylindrical surfaces 2a and 2b formed on the cylinder block 2 are also coaxial with each other, and are perpendicular to the bearing unit central axis of the bearing frame 5 fixed to the cylinder block 2. It has become.
[0014]
The open end of one inner peripheral cylindrical surface 2a formed in the cylinder block 2 is closed by a cylinder head 6 fixed with bolts, and the piston head 1a of the reciprocating member and the inner peripheral cylindrical surface 2a of the cylinder block A working chamber 7 surrounded by the cylinder head 6 is formed. Communication passages 1e, 1f, and 1g to the working chamber 7 are formed in the piston head 1a of the reciprocating member. Each of the communication passages 1e and 1f passes through the piston and has two openings on the cylindrical surface of the side surface of the piston. The communication passages 1e and 1f are different from each other by 90 degrees and intersect at the center of the piston. A communication passage 1e shown in FIG. 1 is a discharge passage, and a communication passage 1f shown in FIG. 4 is a suction passage. The communication passage 1g communicates the intersection of 1e and 1f with the working chamber 7. The cylinder block 2 is formed with two each of an expander section discharge port 2c and an expander section suction port 2d that open to the inner peripheral cylindrical surface 2a. The two expander section discharge ports 2c shown in FIG. 1 are indicated by a broken line on the right side and a dashed line on the other side on the left side. Although it opens to the circumferential cylindrical surface 2a, it opens in the position which mutually opposed substantially 180 degree | times. Two covers 8 fixed to the cylinder block 2 with bolts or the like (not shown) are closed at two openings on the opposite side of the inner peripheral cylindrical surface 2a of the expander section discharge port 2c. The expander section discharge pipe 9 is connected.
[0015]
The two expander section suction ports 2d shown in FIG. 4 are shown with a one-dot chain line on the right side and a broken line on the other side on the left side. Although it opens to the circumferential cylindrical surface 2a, it opens in the position which mutually opposed substantially 180 degree | times. Two covers 10 fixed to the cylinder block 2 with bolts or the like (not shown) are closed at two openings on the opposite side of the inner peripheral cylindrical surface 2a of the expander section suction port 2d. The expander section suction pipe 11 is connected.
[0016]
On the other hand, a working chamber 13 surrounded by the piston head 1b of the reciprocating member 1, the inner peripheral cylindrical surface 2b of the cylinder block 2 and the cylinder head 12 is formed in the upper part. The piston head 1b is formed with a compressor portion suction port 1h, and a suction valve plate 14 is mounted by a rivet 15. The rivet 15 constrains the suction valve plate 14 to be lifted from the upper end surface of the piston head 1b, and allows the refrigerant gas to flow into the working chamber 13 from the suction port 1h in the suction stroke. A compressor section suction pipe 16 is connected to the cylinder block 2, and the inside of the expansion / compressor of the first embodiment becomes the suction pressure of the compressor up to the back surface of the piston head 1b. The suction port 1h and the compressor section suction pipe 16 are communicated with each other. A compressor discharge port 12a is formed in the cylinder head 12, and a discharge valve plate 17 and a discharge valve retainer 18 are fixed by bolts (not shown). The cylinder head 12 is fixed to the cylinder block 2 by bolts together with a discharge chamber cover 20 that surrounds the discharge space 19. A compressor section discharge pipe 21 is connected to the discharge chamber cover 20.
[0017]
A stator portion 22a of a drive motor 22 is fixed to each of the two bearing frames 5 with bolts, and the two drive shafts 4 have a bearing portion 5a sandwiched between the drive arm portion 4a and the opposite side of the drive arm portion 4a. The rotor part 22b is fixed. A balance mass 23 that generates a smaller centrifugal force in the opposite direction to the balance mass 4b is attached to the rotor portion 22b. The two sets of drive motors 22 composed of the stator portion 22a and the rotor portion 22b are the same, but are incorporated in the above-described overall configuration of the expansion / compression device in a posture facing each other, so that two drives The shaft 4 is rotationally driven in opposite directions. In the first embodiment, the right drive motor 22 and the left drive motor 22 in FIG. 1 are configured to rotate in a clockwise direction and a counterclockwise direction as viewed from the right direction in the drawing. Note that the motor cover 24 is fixed to the two bearing frames 5 by fastening them together with fixing bolts to the cylinder block 2.
[0018]
In the above configuration, when the two drive shafts 4 are rotationally driven in directions opposite to each other, the spherical centers of the two spherical bushes 3 that are displaced in the radial direction from the rotational shaft of the drive shaft 4 are in the vertical direction in FIG. A reciprocating member 1 in which two cylindrical arm portions 1c are supported by a spherical bush 3 because they reciprocate in the same phase and reciprocate in mutually opposite phases in the direction perpendicular to the paper surface of FIG. As shown in FIG. 8), the reciprocating motion in the vertical direction of the figure is repeated while reciprocating in the vertical direction. At this time, the two piston side surface openings of each of the communication passages 1e and 1f formed in the piston head 1a of the reciprocating member 1 are displaced from the center of the spherical bush 3 and the rotation shaft of the drive shaft 4. However, the stroke of the oscillating motion is reduced by a ratio obtained by dividing the outer diameter of the piston by the distance between the centers of the two spherical bushes 3 in the oscillating direction. That is, the motion which draws the elliptical locus | trajectory 25 shown by FIG.2, FIG.3, FIG.5 and FIG. 6, respectively is performed.
[0019]
2, 3, 4, and 5, the positions of the expander section discharge port 2 c and the expander section suction port 2 d are shown in the respective cross sections, and the piston heads that are in a position facing them are shown. The positions of the openings of the communication passages 1e and 1f of 1a are indicated by broken lines, and an elliptical locus 25 of the movement is indicated by a one-dot chain line. Furthermore, the direction of movement of the communication passages 1e and 1f when the drive shafts 4 rotate in the aforementioned direction is indicated by arrows.
[0020]
The cylinder block 2 is formed with two each of an expander part discharge port 2c and an expander part suction port 2d that open to the inner peripheral cylindrical surface 2a. The expander part suction port 2d is an expander part discharge port 2c. Smaller than Further, a high-pressure working fluid is supplied through an expander section suction pipe 11 connected to the cover 10, the expander section suction port 2 d is used as a high-pressure working fluid space, and the expander section discharge port 2 c is used as a low-pressure working fluid space. The decompressed working fluid is discharged from the expander section discharge pipe 9 connected to the cover 8.
[0021]
With the above configuration, the working chamber 7 is connected to the expander unit suction port 2d through the communication passage 1f of the piston head 1a only during the initial period of the suction stroke in which the volume increases, and sucks high pressure working fluid. In the latter period of the stroke, the internal working fluid is expanded by increasing the volume by forming a sealed space that is blocked from both the suction and discharge ports. The expander section discharge port 2c is sufficiently large, and the working chamber 7 is electrically connected to the expander section discharge port 2c through the communication passage 1e of the piston head 1a during the entire discharge stroke in which the volume of the expander section decreases. The working fluid is discharged. These suction path and discharge path are inexpensive because there are no moving parts or complicated valve mechanisms.
[0022]
On the other hand, the upper working chamber 13 compresses the refrigerant gas sucked from the compressor portion suction port 1h by the periodic change of the volume accompanying the reciprocating motion of the reciprocating member 1, and then from the compressor portion discharge port 12a. Discharge. That is, the lower working chamber 7 functions as an expander, and the upper working chamber 13 functions as a compressor.
[0023]
The first embodiment having the above-described structure has the following features. In the first embodiment, there are two each of the expander section suction port 2d and the communication path 1f as the suction path, and the two communication paths 1e and the expander section discharge port 2c as the discharge paths. The cylinder block has a pair of openings at positions facing the inner circumferential cylindrical surface 2a of the cylinder block at approximately 180 degrees. The suction pressure and the discharge pressure act on the portions corresponding to the respective port openings on the side surface of the piston head 1a of the reciprocating member to try to press the piston head 1a to the opposite side. Counteract with the same force from the area and pressure openings. Therefore, no force is generated to press the piston head 1a against the inner circumferential cylindrical surface 2a of the cylinder due to the pressure on the side surface.
[0024]
Further, the first embodiment uses the mechanism described in Patent Document 1, and the axial load due to the working chamber pressure on the end surfaces of the piston heads 1a and 1b is viewed from the direction of the load acting line (piston central axis). It is stably supported by the two spherical bushes 3 that are point-symmetric with respect to the load point. Therefore, in this embodiment, no force is generated to press the piston heads 1a, 1b against the inner peripheral cylindrical surfaces 2a, 2b of the cylinder even by the pressure at the piston end surface. That is, according to the first embodiment, there is an effect that it is possible to provide a reciprocating positive displacement machine having a very small sliding load between the piston and the cylinder and a small friction loss.
[0025]
In addition, according to the first embodiment, as described in Patent Document 1, as a basic feature of the mechanism employed, there is also an effect that an excitation force that causes vibration is hardly generated.
[0026]
FIG. 7 shows a cycle configuration diagram when the expansion / compressor according to the first embodiment of the present invention is incorporated in the refrigeration cycle of the refrigeration / air-conditioning equipment. The central expansion / compression machine 26 is an expansion / compression machine according to the first embodiment of FIG. The thick line in the figure is the cycle piping 27, and the arrow on the thick line indicates the flow direction of the internal refrigerant. Under general refrigerant and operating conditions, the refrigerant gas that has been pressurized at the compressor portion of the expansion / compressor 26 to become high temperature and high pressure is discharged from the compressor discharge pipe 21 and passes through the cycle pipe 27 to the condenser 28. In this way, heat is dissipated and condensed to form a high-pressure liquid refrigerant. Part of the high-pressure liquid refrigerant is then transferred to the expander portion of the expander / compressor 26 from the two expander section suction pipes 11 (not shown in FIG. 7; see FIG. 4) via the cycle pipe 27. It flows in and is partly gasified while being decompressed there to increase the entire volume, and flows out from the two expander section discharge pipes 9 in a low-pressure gas-liquid two-phase state. When the refrigerant is carbon dioxide and the discharge pressure reaches supercriticality, the refrigerant flowing into the expander part is not in a liquid state, but in any case, after expansion, a low-pressure gas-liquid two-phase state And flows out of the two expander section discharge pipes 9. Thereafter, it reaches the evaporator 29 via the cycle pipe 27. The other part of the high-pressure refrigerant exiting from the condenser 28 is configured to pass through a cycle piping path provided in parallel with the path passing through the expander. The pressure is reduced by the expansion means 30 and reaches the evaporator 29 via the cycle pipe 27 in a low-pressure gas-liquid two-phase state. The expansion means 30 is based on a throttle like an expansion valve and a capillary tube in a conventional refrigeration cycle, and controls the operating pressure and refrigerant flow rate of the entire refrigeration cycle by changing the amount of the throttle.
[0027]
In this system configuration, the refrigeration capacity, which has been reduced due to the pressure loss when the total amount of high-pressure liquid refrigerant discharged from the condenser in the prior art passes through the throttle such as the expansion means 30, is recovered by the power recovered by the expander. However, the same amount of power consumption can be reduced, but the use of the expansion / compressor 26 according to the first embodiment of the present invention further produces the following effects. In this system, as described above, the refrigerant decompressed in the expander portion of the expander / compressor 26 enters a gas-liquid two-phase state and flows out from the expander section discharge pipe 9. For this reason, there exists a possibility that the lubricating oil adhering to the surface may be washed inside the working chamber 13 of the expander portion by the liquid refrigerant. For this reason, in order to ensure the reliability of the entire expansion / compressor 26 or the entire refrigeration / air conditioning system, other parts (piston heads) such as the inner peripheral cylindrical surface 2a of the cylinder in the inner surface of the working chamber 13 are used. It is necessary to take measures to prevent the sliding portion from being damaged when the lubricating oil on the surface sliding with the portion 1a) is washed with the liquid refrigerant. In the first embodiment of the present invention, there is an effect that the sliding portion can be prevented from being damaged and reliability can be ensured by applying almost no load to the sliding portion.
[0028]
8 to 10 show a pump according to a second embodiment of the present invention. The side cross section of the second embodiment is the same as the side cross section of the lower half expander portion of FIG. In the second embodiment, the two piston heads 31a (one not shown) at both ends of the reciprocating member 31 have the same shape, and have the same working chamber, suction path, and discharge path around them. Shall have. Hereinafter, a different part from the expander part of 1st Example is demonstrated.
[0029]
The two suction ports 32c of the cylinder block 32 shown in FIG. 8 are long in the reciprocating direction of the reciprocating member 31 similarly to the discharge port 32b (not shown, the same as the discharge port 2c in FIG. 1), and the working chamber 33 The working chamber 33 communicates with each other through the communication passages 31e and 31f throughout the entire period during which the volume of the chamber increases. The discharge port 32b also communicates with the working chamber 33 through communication passages 31d and 31f (both not shown; the same as the communication passages 1e and 1g in FIG. 1) throughout the period during which the volume of the working chamber 33 is decreasing. Therefore, the second embodiment functions as a pump that sucks and discharges incompressible liquid. The second embodiment is different from the first embodiment in that the suction and discharge paths have no movable parts or complicated valve mechanisms and are inexpensive and that no sliding load is generated between the piston and the cylinder. Similar effects can be obtained.
[0030]
For the lower expander portion in the first embodiment (FIGS. 1 to 6) of the present invention, when the left and right motors 22 are driven in opposite directions, respectively, in FIGS. 2, 3, 5, and 6. The openings of the communication passages 1e and 1f move in the reverse direction on the elliptical locus 25, and function as a compressor in a state where the suction path and the discharge path are switched.
[0031]
Further, in the pump portion of the second embodiment (FIGS. 8 to 10) of the present invention, when high-pressure oil is introduced into the suction path and the discharge path is depressurized to communicate with low-pressure oil, The drive shaft 4 can function as a hydraulic motor that serves as an output shaft.
[0032]
As described above, according to the description of each embodiment, according to the present invention, it is possible to provide a reciprocating positive displacement machine that can eliminate the need for moving parts for the valve mechanism, and has high productivity and high reliability.
[0033]
In addition, according to the present invention, the sliding load between the piston and the cylinder can be greatly reduced, and the potential for mechanical friction loss and sliding portion damage can be reduced. Therefore, a highly efficient and highly reliable reciprocating positive displacement machine can be achieved. There is an effect that it can be provided.
[0034]
Further, according to the present invention, the sliding load between the piston and the cylinder is greatly reduced, so that the refrigerant that has become a gas-liquid two-phase state in the expansion stroke is worn and burned even if the lubrication state in the working chamber deteriorates. Since sticking can be prevented, there is an effect that the reliability of the refrigeration cycle system for recovering power by the expander can be improved.
[0035]
【The invention's effect】
By using a reciprocating positive displacement machine with improved productivity, efficiency, and reliability, it is possible to increase the practicality of a highly efficient system that recovers power by an expander in a refrigeration cycle.
[Brief description of the drawings]
FIG. 1 is a side sectional view of an entire expansion / compression machine according to a first embodiment of the present invention.
FIG. 2 is a cross-sectional view taken along the line BB in FIG.
3 is a cross-sectional view taken along the line CC in FIG.
4 is a cross-sectional view taken along line AA in FIG.
FIG. 5 is a cross-sectional view taken along line DD in FIG.
6 is a cross-sectional view taken along line EE in FIG.
FIG. 7 is a configuration diagram of a refrigeration cycle when the expansion / compressor according to the first embodiment of the present invention is applied to a refrigeration / air conditioning apparatus.
FIG. 8 is a cross-sectional view in a direction perpendicular to the axis of a pump according to a second embodiment of the present invention.
9 is a cross-sectional view taken along line FF in FIG.
10 is a cross-sectional view taken along line GG in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Reciprocating member, 1a ... Piston head, 1b ... Piston head, 1c ... Arm part, 1d ... Pin, 1e ... Communication path, 1f ... Communication path, 1g ... Communication path, 1h ... Compressor part suction port, 2 ... Cylinder block, 2a ... Inner peripheral cylindrical surface, 2b ... Inner peripheral cylindrical surface, 2c ... Expander section discharge port, 2d ... Expander section suction port, 3 ... Spherical bush, 4 ... Drive shaft, 4a ... Drive arm section 4 ... Balance mass, 5 ... Bearing frame, 5a ... Bearing part, 6 ... Cylinder head, 7 ... Working chamber, 8 ... Cover, 9 ... Expander part discharge pipe, 10 ... Cover, 11 ... Expander part suction pipe, DESCRIPTION OF SYMBOLS 12 ... Cylinder head, 12a ... Compressor part discharge port, 13 ... Working chamber, 14 ... Suction valve plate, 15 ... Rivet, 16 ... Compressor part suction piping, 17 ... Discharge valve plate, 18 ... Discharge valve retainer, 19 ... Discharge space, DESCRIPTION OF SYMBOLS 0 ... Discharge chamber cover, 21 ... Compressor part discharge piping, 22 ... Drive motor, 22a ... Stator part, 22b ... Rotor part, 23 ... Balance mass, 24 ... Motor cover, 25 ... Ellipse locus, 26 ... Expansion / compression 27 ... cycle piping, 28 ... condenser, 29 ... evaporator, 30 ... expansion means, 31 ... reciprocating member, 31a ... piston head, 31b ... arm part, 31c ... pin, 31d ... communication passageway, 31e ... Communication passage, 31f ... Communication passage, 31g ... Communication passage, 32 ... Cylinder block, 32a ... Inner cylindrical surface, 32b ... Pump discharge port 32c ... Pump suction port, 33 ... Work chamber, 34 ... Cover, 35 ... Pump suction pipe .

Claims

A reciprocating member having an outer peripheral cylindrical surface that performs reciprocating motion and a swinging motion about an axis in the reciprocating motion direction; and an inner peripheral cylindrical surface that supports the reciprocating member so that the reciprocating motion and the swinging motion are possible. In a displacement type machine that has a cylinder member having a closed space adjacent to the reciprocating member as a working space, and reciprocates the reciprocating member to change the volume of the working space to transfer and compress the working fluid. A low-pressure working fluid space and the working chamber during a period in which the volume of the working space is increased via a suction port opened in the inner peripheral cylindrical surface of the cylinder member and a suction passage provided in the reciprocating member; Are connected to each other, and a high pressure is generated during at least a part of the period in which the volume of the working space is reduced via the discharge port opened in the inner peripheral cylindrical surface of the cylinder member and the discharge passage provided in the reciprocating member. Working flow A volume communicating the working chamber and the suction port and the discharge port, wherein the suction port and the discharge port have an even number so as to be paired with each other at a position facing substantially 180 degrees on the inner peripheral cylindrical surface of the cylinder member. Shape compressor

A reciprocating member having an outer cylindrical surface that performs reciprocating motion and a swinging motion about an axis in the reciprocating motion direction; and an inner peripheral cylindrical surface that supports the reciprocating member so that the reciprocating motion and the swinging motion are possible. In the positive displacement machine, in which the cylinder member and a closed space adjacent to the reciprocating member are used as a working space, and the reciprocating member is reciprocated to change the volume of the working space to transfer and compress the working fluid. A high-pressure working fluid space and at least a part of a period during which the volume of the working space is increased via a suction port opened in the inner peripheral cylindrical surface of the member and a suction passage provided in the reciprocating member. A low-pressure working fluid is communicated with the working chamber during a period when the volume of the working space is reduced via a discharge port opened on the inner peripheral cylindrical surface of the cylinder member and a discharge passage provided in the reciprocating member. Sky And the working chamber communicate with each other, and each of the suction port and the discharge port has an even number so as to be paired at a position opposed to approximately 180 degrees on the inner peripheral cylindrical surface of the cylinder member. Compressor.

A reciprocating member comprising an outer peripheral cylindrical surface portion that is guided by another member to perform a reciprocating motion and a swinging motion about an axis in the reciprocating motion direction, and two arm portions projecting on opposite sides in a direction perpendicular to the reciprocating motion direction. And a cylinder member having an inner peripheral cylindrical surface portion that guides an outer peripheral cylindrical surface portion of the reciprocating member, and a position displaced radially from the rotation axis while rotating in opposite directions around the coaxial rotation axis, respectively. As a component, there are two shaft members that support one of the arm portions of the reciprocating member so that relative rotation and change of the rotation axis direction are possible, and bearing members that support rotation of the two shaft members. A closed space adjacent to the reciprocating member is used as a working space, and the two reciprocating members are reciprocated by rotation of the two shaft members in opposite directions to change the volume of the working space, Compression In a positive displacement machine, a low-pressure working fluid space during a period in which the volume of the working space is increased via a suction port opened on an inner peripheral cylindrical surface of the cylinder member and a suction passage formed in the reciprocating member. At least one of the periods when the volume of the working space is reduced via the discharge port opened in the inner peripheral cylindrical surface of the cylinder member and the discharge passage provided in the reciprocating member. The working fluid space and the working chamber communicate with each other in a part period, and the suction port and the discharge port are even numbers so as to be paired at positions facing each other at approximately 180 degrees on the inner peripheral cylindrical surface of the cylinder member. A positive displacement compressor characterized by having.

A reciprocating member comprising an outer peripheral cylindrical surface portion that is guided by another member to perform a reciprocating motion and a swinging motion about an axis in the reciprocating motion direction, and two arm portions projecting on opposite sides in a direction perpendicular to the reciprocating motion direction. And a cylindrical member having an inner peripheral cylindrical surface portion for guiding an outer peripheral cylindrical surface portion of the reciprocating member, and a position displaced in a radial direction from the rotational axis while rotating in opposite directions around the coaxial rotational axis, respectively. Two shaft members that support one of the arm portions of the reciprocating member so as to be capable of relative rotation and change in the rotation axis direction, and a bearing member that supports rotation of the two shaft members are constituent elements. A closed space adjacent to the reciprocating member is used as a working space, and the reciprocating member is reciprocated by rotation of the two shaft members in opposite directions to change the volume of the working space, thereby transferring the working fluid. And compression In the positive displacement machine, at least a part of a period during which the volume of the working space is increased via a suction port opened on the inner peripheral cylindrical surface of the cylinder member and a suction passage provided in the reciprocating member. The high-pressure working fluid space and the working chamber communicate with each other during the period, and the volume of the working space decreases via a discharge port opened on the inner peripheral cylindrical surface of the cylinder member and a discharge passage provided in the reciprocating member. The low-pressure working fluid space and the working chamber communicate with each other during the period, and the suction port and the discharge port are respectively paired at positions facing each other at approximately 180 degrees on the inner peripheral cylindrical surface of the cylinder member. A positive displacement compressor characterized by having an even number.

The working chamber space formed adjacent to one end of the reciprocating member communicates with the high-pressure working fluid space during a part of the period during which the volume is increasing, and the low-pressure operation is performed during the period when the volume is decreasing. 5. A function as an expander part by communicating with a fluid space, and a working space formed adjacent to the other end of the reciprocating member as a compressor part. The displacement machine described.

6. The expander part of the positive displacement machine of claim 5 is used as an expansion means, and the compressor part of the positive displacement machine of claim 5 is used as a compression means to compress low-pressure refrigerant gas, which is compressed to a high temperature and high pressure. A cooling means for radiating heat from the refrigerant gas, an expansion means for depressurizing the cooled high-pressure refrigerant, a heating means for evaporating the liquid refrigerant portion after being depressurized, and connecting them together to close. A refrigeration cycle apparatus having a pipe forming a cycle as a component.

The refrigeration cycle apparatus according to claim 6, wherein carbon dioxide is used as the refrigerant gas.