JP3886186B2

JP3886186B2 - Reciprocating piston compressor

Info

Publication number: JP3886186B2
Application number: JP31457596A
Authority: JP
Inventors: 郁友梅岡; 泰彦田中; 一朗喜多
Original assignee: 松下冷機株式会社
Priority date: 1996-11-26
Filing date: 1996-11-26
Publication date: 2007-02-28
Anticipated expiration: 2016-11-26
Also published as: JPH10159718A

Description

【０００１】
【発明の属する技術分野】
本発明は、家庭用冷蔵庫等に用いられる比較的小型の往復ピストン圧縮機に関するものである。
【０００２】
【従来の技術】
近年、往復ピストン圧縮機は、小型化、組立の簡素化の観点から種々の改良がなされている。また、市場からは高効率化、低騒音化の要望も高い。
【０００３】
従来の往復ピストン圧縮機としては、特開平４−１６４１７４号公報や特公平５−８４８３７号公報に示されているものがある。
【０００４】
以下、図１６、図１７および図１８を参照にしながら、上記した特公平５−８４８３７号公報に示されている従来の往復ピストン圧縮機について説明する。
【０００５】
図１６は、従来の往復ピストン圧縮機の縦断面図、図１７は、図１６の拡大図であり、往復ピストン圧縮機を組み立てる前のコンロッドとピストンの分解図、図１８はコンロッドの大端部と小端部の分解組立平面図である。
【０００６】
図１６、図１７、図１８において、モータ・圧縮機ユニット１は、スプリング２によりハウジング３内に支持されている。クランクケース４は、モータの固定子５を据え付けるための支持台の役目をし、モータの回転子８を連結しているクランク軸７を支持するための軸受部６を備えている。また、クランクケース４はその内部でピストン１０が往復するシリンダ９を備えている。クランク軸７の上端には、偏芯軸１１が備えられている。シリンダ９にはシリンダ９の端部であってクランク軸７の反対側に、公知の方法で製造できるバルブプレート１７とシリンダヘッド１８が取り付けられている。コンロッド１９は小端部２０と大端部３０とからなり、ピストン１０とクランク軸７の偏芯軸１１とを連結している。
【０００７】
コンロッド１９の小端部２０は、小端孔部２１とここから半径方向にのびる長い第１突起部２２とからなり、この第１突起部２２は、コンロッド１９の腕部分を規定し、小端孔部２１は、ピストンピン１５によりピストン１０に連結されている。
【０００８】
コンロッド１９の大端部３０は、縦の溝３３を有する半径方向に伸びる短い第２突起部３２を備える大端孔部３１からなり、この大端孔部３１には、クランク軸７の偏芯軸１１が挿入されている。
【０００９】
大端孔部３１の溝３３は、第２突起部３２の内部に形成され、対抗し且つ平行である２個の面３４と、Ｖ字型に形成された内部の２個の第２端面３５とを備え、この第２端面３５の頂部には縦の窪み３６が備えられている。第１突起部２２の端部２７には、面２４とＶ字型の２個の第１端面２５が形成され、これらの第１端面２５は、溝３３の第２端面３５とそれぞれ完全に当接するように構成されている。
【００１０】
以上のように構成された従来の往復ピストン圧縮機について、以下その動作を説明する。
【００１１】
クランクケース４の軸受部６にクランク軸７が挿入された状態でコンロッド１９の大端部３０の大端孔部３１を偏芯軸１１に挿入し、小端孔部２１にピストンピン１５を挿入することで連結したピストン１０と小端部２０をシリンダ９の反クランク軸から挿入する。
【００１２】
その後、小端部２０の第１突起部２２の端部２７を大端部３０の第２突起部３２の溝３３に嵌め込み、第１突起部２２の面２４、第１端面２５と第１突起部３２の溝３３の面３４、第２端面３５をそれぞれ当接させ、溶接などの方法で固定される。大端部３０と、小端部２０が固定されたコンロッド１９は、クランク軸７の回転をピストン１０の往復動に変換して力を伝達することによりシリンダ９内の気体を圧縮する。
【００１３】
【発明が解決しようとする課題】
しかしながら、上記の従来の構成では、コンロッド１９の小端部２０と大端部３０の接合は、端部２７と溝３３の嵌め込みによって行われるので、端部２７の面２４、第１端面２５と溝３３の面３４、第２端面３５は、非常に高精度な面仕上げを行う必要があり、加工が困難である欠点があった。
【００１４】
また、上記従来の構成は、大端孔部３１の孔の軸心と溝３３の面３４、第２端面３５との平行、あるいは小端孔部２１の軸心と端部２７の面２４、第１端面２５との平行が少しでもずれるとコンロッド１９の大端孔部３１と小端孔部２１の軸がねじれたり、上下方向に力が加わった時には規定する端面がなく、上下方向の固定が非常に不安定となり、コンロッド１９のクランク軸７やピストンピン１５へのこじりが発生し、圧縮機の回転負荷を増大させ、騒音または振動の増大や効率低下を招く欠点があった。
【００１５】
本発明は、従来の課題を解決するもので、高精度で加工および組立が容易で、高効率で低騒音、低振動の往復ピストン圧縮機を提供することを目的とする。
【００１６】
また、上記従来の構成は、コンロッド１９の小端部２０と大端部３０の接合部への給油はハウジング３内のミスト状の油に頼っており、積極的な給油がなく、接合部の金属摩耗による信頼性の悪化を招く欠点があった。
【００１７】
本発明の他の目的は、コンロッド１９の接合部への積極的な給油を行い、信頼性を向上させることである。
【００１８】
【課題を解決するための手段】
この目的を達成するため本発明は、ピストンピンにより小端孔でピストンに連結された小端部と、大端孔でクランク軸の偏芯軸に連結された大端部を有するコンロッドを備える往復ピストン圧縮機であって、コンロッドの大端部は円筒形の円孔部とこれに連通する固定孔を有する突起部を有し、円孔部は底形状が半球形または略円錘形で、突起部の端面部から大端孔の中心方向へ大端孔に貫通しない深さで設けられており、小端部は半径方向に長い円筒形のロッド部を有し、ロッド部は端部に係止孔と先端が半球形または略円錘形の係止部を構成しておりこの係止部を突起部の円孔部に遊嵌または軽圧入すると共に、固定孔と係止孔を連通してロッキングピンを挿入することにより、係止部と円孔部を係止し、コンロッドの小端部の小端孔と大端部の大端孔の幾何学的軸の配置を同一平面上に維持するものである。
【００１９】
これにより、往復ピストン圧縮機の加工及び、組立が精度良く行われ、高効率で低騒音、低振動にすることができる。
【００２０】
また、ロッド部の円筒形の係止部と、突起部の円筒形の円孔部に平面部を設けるものである。
【００２１】
これにより、往復ピストン圧縮機の組立が容易に行えると共に、係止部の軸回りの挙動を規制でき、コンロッド挙動を安定させ、効率の低下や騒音、振動の増大を防止できる。
【００２２】
また、円孔部の頂部と大端孔を連通させる油孔を設け、この油孔とクランク軸の偏芯軸の油溝と連通させるものである。
【００２３】
これにより、コンロッドの小端部と大端部との接合部への積極的な給油が行え、金属摩耗を軽減し、往復ピストン圧縮機の信頼性を向上できる。
【００２４】
また、ロッド部の円筒形の係止部に係止溝と、突起部の平面部に固定溝を設け、ロッド部の係止部を突起部の円孔部に遊嵌又は軽圧入すると共に、固定溝から係止溝へ連通して固定板を嵌め込むことで、係止部と円孔部を係止し、コンロッドの小端部の小端孔と大端部の大端孔の幾何学的軸の配置を同一平面上に維持するものである。
【００２５】
これにより、コンロッドの小端部と大端部との固定を強固なものにすることができ、コンロッド挙動を安定させることができ、効率の低下や騒音、振動の増大を防止できる。
【００２６】
また、ロッド部と係止部との間に、円孔部との嵌合時に突起部の端面部と接合する補助平面部を有する保持部を設けるものである。
【００２７】
これにより、組立性が向上すると共に、補助平面部と端面部に働く荷重が軽減され、コンロッド挙動を安定させ、効率の低下や騒音、振動の低下を防止できる。
【００２８】
また、ロッド部と係止部との間に小端孔の円筒軸方向に平行な係止端面を有する第２係止突起部を設け、且つ大端部の突起部に大端孔の円筒軸方向に平行な固定端面を設け、小端部と大端部の連結時に係止端面と固定端面が接合し、小端部と大端部の嵌合位置を規定させるものである。
【００２９】
これにより、高精度で組立することができると共に、コンロッド挙動を安定させ、効率の低下や騒音、振動の増大を防止することができる。
【００３０】
【発明の実施の形態】
本発明は、ピストンピンにより小端孔でピストンに連結された小端部と、大端孔でクランク軸の偏芯軸に連結された大端部を有するコンロッドを備える往復ピストン圧縮機であって、コンロッドの大端部は円筒形の円孔部とこれに連通する固定孔を有する突起部を有し、円孔部は底形状が半球形または略円錘形で、突起部の端面部から大端孔の中心方向へ大端孔に貫通しない深さで設けられており、小端部は半径方向に長い円筒形のロッド部を有し、ロッド部は端部に係止孔と先端が半球形または略円錘形の係止部を構成しており、この係止部を突起部の円孔部に遊嵌または軽圧入すると共に、固定孔と係止孔を連通してロッキングピンを挿入することにより、係止部と円孔部を係止し、コンロッドの小端部の小端孔と大端部の大端孔の幾何学的軸の配置を同一平面上に維持するものである。
【００３１】
そして、圧縮機の運転中にあらゆる方向からコンロッドへ荷重が働く時に、小端部の半球形または略円錘形の係止部の先端は、大端部の円孔部の半球形または略円錘形の底面で面接触し、荷重が分散されエッジ部等での集中荷重を受けることがなくなる。また、大端部を小端部へ連結するときに、大端部の係止部の先端が半球形または略円錘形をしており、エッジ部がなく容易に小端部の円孔部へ嵌め込むことができる。さらに、ロッキングピンを小端部の係止孔と大端部の固定孔へ挿入して、両者を連結するときに、ロッキングピンは、自己の柔軟性により小端部の小端孔と大端部の大端孔のわずかな軸の振れを吸収して小端孔と大端孔の軸が一致するように自己補正して安定する作用がある。また、小端部のロッド部及び、大端部の円孔部は円筒形であることから、容易に高精度な加工ができる。
【００３２】
これにより、圧縮機の組立時や運転時にねじれやこじりによる回転負荷の増大が防止されることとなる。
【００３３】
また、ロッド部の円筒形の係止部と、突起部の円筒形の円孔部に平面部を設けるものである。
【００３４】
そして、小端部の係止部を大端部の円孔部へ嵌め込むときに、係止部の平面部と円孔部の平面部が嵌合位置決めとなり、係止部の係止孔と円孔部の固定孔がほぼ一致し、ロッキングピンの挿入時に孔の位置あわせをすることなく、容易に組み立ることが可能になると共に、係止部の軸回りの挙動が防止され、コンロッドの挙動が安定することとなる。
【００３５】
また、円孔部の頂部と大端孔を連通させる油孔を設け、この油孔とクランク軸の偏芯軸の油溝と連通させるものである。
【００３６】
そして、圧縮機の運転中に小端部の係止部と大端部の円孔部への積極的な給油が行われ、金属接触による摩耗が軽減されることとなる。
【００３７】
また、ロッド部の円筒形の係止部に係止溝と、突起部の平面部に固定溝を設け、ロッド部の係止部を突起部の円孔部に遊嵌又は軽圧入すると共に、固定溝から係止溝へ連通して固定板を嵌め込むことで、係止部と円孔部を係止し、コンロッドの小端部の小端孔と大端部の大端孔の幾何学的軸の配置を同一平面上に維持するものである。
【００３８】
そして、大端部と小端部が固定板で強固に固定されることで、コンロッド挙動が安定することとなる。
【００３９】
また、ロッド部と係止部との間に、円孔部との嵌合時に突起部の端面部と接合する補助平面部を有する保持部を設けたものである。
【００４０】
そして、係止部の円孔部への嵌め込み代が規定され、組立性が向上すると共に、端面部と補助平面部との接合面へ受ける荷重の分散が図れ、コンロッド挙動が安定することとなる。
【００４１】
また、ロッド部と係止部との間に小端孔の円筒軸方向に平行な係止端面を有する第２係止突起部を設け、且つ大端部の突起部に大端孔の円筒軸方向に平行な固定端面を設け、小端部と大端部の連結時に係止端面と固定端面が接合し、小端部と大端部の嵌合位置を規定させるものである。
【００４２】
そして、係止部を円孔部へ嵌め込む時に、係止端面と固定端面の接合により、係止部円筒形の軸回り位置と、嵌め込み代が規定され、係止孔と固定孔へロッキングピンを挿入する時に微妙な孔位置調整をする必要がなく、容易に組立が可能となると共に、係止端面と固定端面のため、コンロッドの係止部の軸回りや左右方向が固定され、コンロッド挙動が安定することとなる。
【００４３】
【実施例】
以下、本発明による往復ピストン圧縮機の実施例について、図面を参照しながら説明する。なお、従来と同一構成については、同一符号を付して詳細な説明を省略する。
【００４４】
（実施例１）
図１は、本発明の実施例１による往復ピストン圧縮機の縦断面図である。図２は図１の拡大図であり、往復ピストン圧縮機を組み立てる前のコンロッドとピストンの分解図、図３は、図１のコンロッドの組立前の平面図、図４は、図１のコンロッドの組立時の部分縦断面図である。
【００４５】
図１において、１９はコンロッドで、一端を小端部５０の小端孔５１に遊嵌されたピストン１５でピストン１０と連結され、他端を大端部５２の大端孔５３で、クランク軸７の偏芯軸１１に遊嵌して連結されている。
【００４６】
図２において、ピストン１０と、ピストンピン１５と小端部５０は、シリンダ９の反クランク軸７側から挿入され、コンロッド１９の大端部５２は、クランク軸７の偏芯軸１１に鉛直上方から挿入される。
【００４７】
コンロッド１９の大端部５２は、円周方向に円孔部５４を有すると共に、円孔部５４と貫通する固定孔５５を有する突起部５６を備える。円孔部５４は、大端孔５３と直角を成し、突起部５６の端面部５７から大端孔５３に貫通しない深さで加工されている。小端部５０は、小端孔５１と直角を成すロッド部５８が円周方向に伸びており、その先端には係止孔５９を有した係止部６０がある。
【００４８】
図３、図４において、６１は係止部６０の先端で、半球形または、略円錘形に加工された係止突起部である。６２は係止突起部６１の係止頂部であり、丸く加工されている。６３は円孔部５４の半球形または略円錘形に加工された固定溝部であり、６４は固定溝部の溝頂部である。
【００４９】
係止部６０を円孔部５４に挿入した後、大端部５２の突起部５６の固定孔５５からロッキングピン６５を小端部５０の係止部６０の係止孔５９へ挿入することで、コンロッド１９の小端部５０と大端部５２は連結固定される。
【００５０】
以上のような構成において、以下その動作を説明する。
円孔部５４は小端部５０の連結部である係止部６０は、いずれも円筒形であるので加工が簡単でしかも寸法精度が出やすい。
【００５１】
係止部６０を円孔部５４へ遊嵌または軽圧入するときに、係止部６０の先端である係止突起部６２は半球形または略円錘形であるので円孔部５４へスムーズに嵌め込まれる。
【００５２】
また、係止部６０と円孔部５４はいずれも円筒形であるので、円筒軸回りに若干振らせることができ、小端孔５１と大端孔５３の円筒軸が組立時にねじれて入りにくいこともなくなる。
【００５３】
そして、係止部６０を円孔部６０を円孔部５４へ嵌め込み後、係止頂部６２は丸く加工されていることから、溝頂部６４とのクリアランスをわずかに残して嵌め込まれる。このとき、わずかなアッセンブルオイルがこのクリアランスに保持されている。
【００５４】
次に、ロッキングピン６５を係止孔５９と固定孔５５へ挿入すると、ロッキングピン６５は、自己の変形で嵌め込み時にわずかにねじれている小端孔５１と大端孔５３の円筒軸のねじれを同一軸方向に補正して係止部６０を円孔部５４へ固定する。
【００５５】
さらに、圧縮機が運転中に圧縮負荷等の要因で小端孔５１と大端孔５３の円筒軸のねじれが発生したとき、ロッキングピン６５はこの負荷によりわずかに変形して圧縮機メカのバランスが良好なところで安定する。
【００５６】
また、コンロッド１９は回転挙動を並進挙動に変換していることから、圧縮機の運転中に、大端部５２は係止部６０を介して小端部５０へ、図３に示す前後、左右方向及び、わずかであるが図４に示す上下方向等のあらゆる方向の力が係止部６０と円孔部５４へ働くこととなる。この時に、係止部６０の先端が半球形または略円錘形に加工されていることから、あらゆる方向に対面する面が形成される。このため、小端部５０と大端部５２の円筒軸は圧縮機の運転中において、同一方向に安定し、クランク軸７の回転力を係止部６０での損失をほとんどなしに、ピストンピン１５へ力を伝達することができる。
【００５７】
以上のように本実施例の往復ピストン圧縮機は、コンロッド１９の大端部５２は円筒形の円孔部５４とこれに連通する固定孔５５を有する突起部５６を有し、円孔部５４は底形状が半球形または略円錘形で、突起部５６の端面部５７から大端孔５３の中心方向へ大端孔５３に貫通しない深さで設けられており、小端部５０は半径方向に長い円筒形のロッド部５８を有し、ロッド部５８は端部に係止孔５９と先端が半球形または略円錘形の係止部６０を構成しており、この係止部６０を突起部５６の円孔部５４に遊嵌または軽圧入すると共に、固定孔５５と係止孔５９を連通してロッキングピン６５を挿入することにより、係止部６０と円孔部５４を係止し、コンロッド１９の小端部５０の小端孔５１と大端部５２の大端孔５３の幾何学的軸の配置を同一平面上に維持したもので、高精度で加工、組立が容易で、小端孔５１と大端孔５３の円筒軸のねじれに起因する回転負荷の増大による効率の低下や、小端孔５１とピストンピン１５や、大端孔５３と偏芯軸１１、係止部６０と円孔部５４等の異常なこじりによる騒音、振動の増大を防止することができる。
【００５８】
（実施例２）
図５は、本発明の実施例２による往復ピストン圧縮機のコンロッドの組立前の平面図、図６は図５のＡ矢視からの組立前の大端部Ａ矢視図。図７はコンロッドの組立時の部分縦断面図である。実施例１と同一構成については同一符号を付して詳細な説明を省略する。
【００５９】
図５、図６、図７において、７０は、大端部５２の円筒形の円孔部５４の円筒軸方向に設けられた固定平面部である。固定溝部６３は固定平面部７０のため、円孔部５４の円筒径より１段径を小さくして加工されている。７１は、小端部５０の円筒形の係止部６０の円筒軸方向に設けられた係止平面部である。固定溝部６３と同様に、係止突起部６１は係止平面部７１のため、係止部６０の円筒径より１段径を小さくして加工されている。
【００６０】
以上のような構成において、以下その動作を説明する。
係止部６０を円孔部５４へ嵌め込むとき、係止平面部７１と固定平面部７０が一種の位置決めガイダーの役目をはたし、嵌め込みと同時に微妙にずれていた係止孔５９と固定孔５５は精度良く一致し、ロッキングピン６５を簡単に挿入できる。
【００６１】
また、係止部６０の軸回り挙動が、係止平面７０と固定平面７１の接合により、規制されコンロッド１９の挙動が安定する。
【００６２】
以上のように本実施例の往復ピストン圧縮機は、ロッド部５８の円筒形の係止部６０に係止端面部７１を設け、突起部５６の円筒形の円孔部５４に固定平面部７０を設けた構成としているので、コンロッド１９の組立時、係止部６０を円孔部５４へ嵌め込むと同時に係止孔５９と固定孔５５の位置が精度良く一致し、ロッキングピン６５の挿入が簡単に行え、組立を容易にできる。
【００６３】
また、係止部６０の軸回り挙動が規制され、コンロッド挙動を安定させることができる。
【００６４】
なお、本実施例において、係止平面部７１から係止孔５９が設けられ、固定平面部７０は固定孔５５から設けられているが、これらの平面部が円筒形の周辺のどの位置にあろうとも同様の効果が得られるものである。
【００６５】
（実施例３）
図８は、本発明の実施例３による往復ピストン圧縮機の吸入行程時のコンロッドと偏心軸の部分縦断面図、図９は圧縮行程時のコンロッドと偏芯軸の部分縦断面図である。実施例１と同一構成については同一符号を付して詳細な説明を省略する。
【００６６】
図８、図９において、７５はクランク軸７内に設けられた第１給油孔で、偏芯軸１１内に設けられた第２給油孔７６と連通している。第２給油孔７６は偏芯軸１１の上方端面に開放し、且つ第２給油孔７６の途中から半径方向へ、偏芯軸１１の外周の油溝７８に連通する横油孔７７が設けられている。横油孔７７と油溝７８はクランク軸７の軸心方向側に向けられている。７９は固定溝部６３の溝頂部６４から大端孔５３へ連通している連通油孔である。
【００６７】
以上のような構成において、以下その動作を説明する。
図８、図９に示している点は油粒を表し、矢印は油の流れを示している。
【００６８】
圧縮機の吸入行程時において、ハウジング３の底部に溜まっている潤滑油（図示せず）は、圧縮機の回転に伴い、クランク軸７の第１給油孔７５の遠心ポンプ作用により、第２給油孔７６へ押し上げられる。そして、偏芯軸１１の回転による遠心力により、油粒は第２給油孔７６から横油孔７７を介して偏芯軸１１の外周に設けられている油溝７８へ導かれる。また、一部の油粒は偏芯軸１１の上方からハウジング３内へ放出される。
【００６９】
そこで、図８のように圧縮機の吸入行程時においては、油溝７８がクランク軸７の軸心方向に位置しているため、油溝７８とコンロッド１９の大端部５２に設けられた連通油孔７９とが連通する。さらに、小端部５０は反クランク軸７側へ引っ張られ、大端部５２はクランク軸７側へ引っ張られる。これにより、係止突起部６１と固定溝部６３との間にわずかな隙間が生じることとなり、遠心力により油溝７８へ到達した油粒はその慣性力を失うことなく連通油孔７９をとおり、係止突起部６１と固定溝部６３のわずかな隙間へ導かれる。
【００７０】
また、図９のような圧縮行程時においては、油溝７８と連通油孔７９は連通せず、且つ小端部５０から圧縮荷重を受け、係止突起部６１と固定溝部６３は互いに押し付け合うこととなる。これにより、吸入行程時に隙間に導かれた油粒は押し付けられ、わずかな隙間からロッキングピン６５、または、連通油孔７９を逆流し、偏芯軸１１の上下部からハウジング３内へ放出される。また、横油孔７７を介して油溝７８へ導かれた油粒は、大端孔５３と偏芯軸１１の潤滑油として給油されることとなる。
【００７１】
このことから、潤滑油はコンロッド１９の連結部である係止突起部６１と固定溝部６３へまんべんなく給油されると共に、潤滑油が循環することで、連結部周辺の冷却効果としても働き、摺動損失を軽減し、金属接触による摩耗を防止することができる。
【００７２】
以上のように本実施例の往復のピストン圧縮機は、大端孔５３と固定溝部６３の溝頂部６４と連通した連通油孔７９を設け、且つ偏芯軸１１の油溝７８と連通油孔７９を連通させることから構成されているので、潤滑油をコンロッド１９の連結部である係止突起部６１と固定溝部６３へ積極的な給油を行うことができる。これにより、摺動損失の増大と金属接触による摩耗を防止することができる。
【００７３】
なお、本実施例において、油溝７８と連通油孔７９は吸入行程時に連通するとしたが、その外の行程時または常時連通しても良く、同様の効果が得られるものである。
【００７４】
（実施例４）
図１０は、本発明の実施例４による往復ピストン圧縮機のコンロッドの組立前の平面図、図１１は、図１０のコンロッドの組立時の部分縦断面図である。実施例１と同一構成については同一符号を付して詳細な説明を省略する。
【００７５】
図１０、図１１において、８０は小端部５０の円筒形の係止部６０の外周に設けられた係止溝８０であり、８１は大端部５２の突起部５６に設けられた固定溝である。固定溝８１は円孔部５４に一部連通している。８２は係止部６０を円孔部５４へ固定するための固定板で、固定板８２の先端は鍵条の突起を構成するカギ部を有している。
【００７６】
以上のような構成において、以下その動作を説明する。
係止部６０を円孔部５４へ嵌め込むと、係止溝８０と固定溝８１の溝が重なる。その後、固定板８２を固定溝８１から係止溝８０へ連通して挿入され、且つ固定板８２の先端であるカギ部８３が突起部５６の端面へ嵌め込まれる。これにより、係止部６０は円孔部５４の底部へ押し付けられ固定される。
【００７７】
このことから、係止突起部６１と固定溝部６３で受けていた荷重を殆ど固定板８２で受けることとなり、コンロッド１９の連結を強固にすることができ、コンロッド挙動が安定する。
【００７８】
以上のように本実施例の往復ピストン圧縮機は、小端部５０の係止部６０の外周に係止溝８０と、大端部５２の突起部５６に円孔部５４に連通する固定溝８１を設け、係止部６０を円孔部５４へ嵌め込んだ後、先端にカギ部８３を有する固定板８２を固定溝８１から係止溝８０へ連通して嵌め込み、小端部５０と大端部５２を連結固定する構成とすることで、係止部６０は円孔部５４へ強固に固定され、圧縮機運転中にコンロッド１９へ働く荷重の殆どを固定板８２で支え、コンロッド挙動を安定させることができる。
【００７９】
（実施例５）
図１２は、本発明の実施例５による往復ピストン圧縮機のコンロッドの組立前の平面図、図１３は、図１２のコンロッドの組立時の部分縦断面図である。実施例１と同一構成については同一符号を付して詳細な説明を省略する。
【００８０】
図１２、図１３において、８５は大端部５２の突起部５６の端面部５７の平面と相対する平面を有する補助平面部８６を有する小端部５０のロッド部５８と係止部６０との間に設けられた保持部である。
【００８１】
以上のような構成において、以下その動作を説明する。
係止部６０を円孔部５４へ嵌め込むときに、補助平面部８６が端面部５７と接合する。これにより、係止部６０の円孔部５４へ嵌め込み代が規定でき、ロッキングピン６５を簡単に係止孔５９と固定孔５５へ挿入し、コンロッド１９を組み立てることができる。
【００８２】
また、圧縮機の圧縮行程時に受ける荷重を補助平面部８６で受けることができ、コンロッド１９の挙動を安定させることができる。
【００８３】
以上のように本実施例の往復ピストン圧縮機は、係止部６０とロッド部５８との間に、突起部５６の端面部５７に相対する補助平面部８６を有した保持部８５を設ける構成とすることで、係止部６０の円孔部５４への嵌め込み代が規定でき、簡単に、コンロッド１９を組み立てることができると共に、圧縮行程時の荷重を補助平面部で受けることで、コンロッド１９の挙動を安定させることができる。
【００８４】
なお、本実施例には、係止突起部６１と固定溝部６３を設けているが、無くても同様の効果が得られる。
【００８５】
（実施例６）
図１４は、本発明の実施例６に依る往復ピストン圧縮機のコンロッドの組立前の平面図、図１５は、図１４のコンロッドの組立時の部分縦断面図である。実施例１と同一構成については同一符号を付して詳細な説明を省略する。
【００８６】
図１４、図１５において、９０は小端孔５１の円筒軸と平行に設けられた係止端面９１を有するロッド部５８と係止部６０との間に設けられた第２係止突起部であり、９２は係止端面９１と相対する大端孔５３の円筒軸と平行に設けられた突起部５６の固定端面である。
【００８７】
以上のような構成において、以下その動作を説明する。
係止部６０を円孔部５４へ嵌め込むときに、係止端面９１と固定端面９２が接合し、係止部６０の嵌め込み代と、左右方向の位置を規定することから、係止孔５９と固定孔５５の位置が精度良く一致する。これにより、ロッキングピン６５を簡単に係止孔５９と固定孔５５へ挿入することができ、コンロッド１９の組立を容易に行うことができる。
【００８８】
また、第２係止突起部９１のため、圧縮機の運転中に、小端部５０と大端部５２が係止部６０の軸回りや左右方向にずれることを規制し、コンロッド１９の連結を強固にでき、コンロッド１９の挙動を安定させることができる。
【００８９】
以上のように本実施例の往復ピストン圧縮機は、係止部６０とロッド部５８との間に小端孔５１の円筒軸と平行な係止端面９１を有する第２係止突起部を設け、それに相対する大端孔５３の円筒軸と平行な固定端面９２を突起部５６に設けた構成とすることで、係止部６０と円孔部５４との嵌め込み時に係止端面９１と固定端面９２とが接合し、係止孔５９と固定孔５５を精度良く一致させることができ、組み立てを容易に行うことができる。また、小端部５０と大端部５２との係止部６０の軸回りや左右方向の固定を強固にすることができ、コンロッド１９の挙動を安定させることができる。
【００９０】
なお、本実施例には、係止突起部６１と固定溝部６３を設けているが、無くても同様の効果が得られる。
【００９１】
【発明の効果】
以上説明したように本発明は、ピストンピンにより小端孔でピストンに連結された小端部と、大端孔でクランク軸の偏芯軸に連結された大端部を有するコンロッドを備える往復ピストン圧縮機であって、コンロッドの大端部は円筒形の円孔部とこれに連通する固定孔を有する突起部を有し、円孔部は底形状が半球形または略円錘形で、突起部の端面部から大端孔の中心方向へ大端孔に貫通しない深さで設けられており、小端部は半径方向に長い円筒形のロッド部を有し、ロッド部は端部に係止孔と先端が半球形または略円錘形の係止部を構成しており、この係止部を突起部の円孔部に遊嵌または軽圧入すると共に、固定孔と係止孔を連通してロッキングピンを挿入することにより、係止部と円孔部を係止し、コンロッドの小端部の小端孔と大端部の大端孔の幾何学的軸の配置を同一平面上に維持することで、高精度に加工、組立が容易にでき、且つ小端孔と大端孔のねじれや嵌合物とのこじりを防止することができ、回転負荷の増大による効率低下と、騒音、振動の増大を防止することができる。
【００９２】
また、ロッド部の円筒形の係止部と、突起部の円筒形の円孔部に平面部を設けたことで、係止部を円孔部へ嵌め込む時の位置決めができ、コンロッドの組立を精度良く行うことができると共に、係止部の軸回りが固定され、回転負荷の増大による効率低下や騒音、振動の増大を防止できる。
【００９３】
また、円孔部の頂部と大端孔を連通させる油孔を設け、この油孔とクランク軸の偏芯軸の油溝と連通させることで、係止部と円孔部へ積極的な給油が行え、金属接触による摩耗を防止でき、信頼性を向上させることができる。
【００９４】
また、ロッド部の円筒形の係止部に係止溝と、突起部の平面部に固定溝を設け、ロッド部の係止部を突起部の円孔部に遊嵌又は軽圧入すると共に、固定溝から係止溝へ連通して固定板を嵌め込むことで、係止部と円孔部を係止し、コンロッドの小端部の小端孔と大端部の大端孔の幾何学的軸の配置を同一平面上に維持することで、係止部と円孔部との連結を固定板で強固に行うことができ、コンロッドの挙動を安定させることができる。これにより、連結のゆる等に起因する圧縮機の回転負荷の増大による効率の低下や騒音、振動の増大を低減することができる。
【００９５】
また、ロッド部と係止部との間に、円孔部との嵌合時に突起部の端面部と接合する補助平面部を有する保持部を設けたことで、係止部と円孔部の連結が効率良く行われると共に、補助平面部と端面部で圧縮時に働く荷重を分散させることができ、コンロッドの挙動を安定させることができる。これにより、圧縮機の回転負荷の増大による効率の低下や騒音、振動の増大を防止できる。
【００９６】
また、ロッド部と係止部との間に小端孔の円筒軸方向に平行な係止端面を有する第２係止突起部を設け、且つ大端部の突起部に大端孔の円筒軸方向に平行な固定端面を設け、小端部と大端部の連結時に係止端面と固定端面が接合し、小端部と大端部の嵌合位置を規定させることで、精度良く係止部と円孔部を連結することができ、組立性が向上すると共に、コンロッドの係止部の軸回りや、左右方向のずれが防止され、コンロッドの挙動が安定する。これにより、回転負荷の増大による効率の低下や騒音、振動の増大を防止することができる。
【図面の簡単な説明】
【図１】本発明による往復ピストン圧縮機の実施例１の縦断面図
【図２】同実施例の往復ピストン圧縮機の往復ピストンの往復ピストン圧縮機を組み立てる前のコンロッドとピストンの分解図
【図３】同実施例の往復ピストン圧縮機のコンロッドの組立前の平面図
【図４】同実施例の往復ピストン圧縮機のコンロッドの組立時の部分縦断面図
【図５】本発明の往復ピストン圧縮機の実施例２のコンロッド組立前の平面図
【図６】本発明の往復ピストン圧縮機の実施例２のコンロッドの組立前の大端部Ａ矢視図
【図７】本発明の往復ピストン圧縮機の実施例２のコンロッドの組立時の部分縦断面図
【図８】本発明の往復ピストン圧縮機の実施例３の吸入行程時のコンロッドと偏芯軸の部分縦断面図
【図９】本発明の往復ピストン圧縮機の実施例３の圧縮行程時のコンロッドと偏芯軸の部分縦断面図
【図１０】本発明の往復ピストン圧縮機の実施例４のコンロッドの組立前の平面図
【図１１】本発明の往復ピストン圧縮機の実施例４のコンロッドの組立時の部分縦断面図
【図１２】本発明の往復ピストン圧縮機の実施例５のコンロッドの組立前の平面図
【図１３】本発明の往復ピストン圧縮機の実施例５のコンロッドの組立時の部分縦断面図
【図１４】本発明の往復ピストン圧縮機の実施例６のコンロッドの組立前の平面図
【図１５】本発明の往復ピストン圧縮機の時実施例６のコンロッドの組立時の部分縦断面図
【図１６】従来の往復ピストン圧縮機の縦断面図
【図１７】従来の往復ピストン圧縮機の組み立てる前のコンロッドとピストンの分解図
【図１８】従来の往復ピストン圧縮機のコンロッドの大端部と小端部の分解組立平面図
【符号の説明】
３ハウジング
７クランク軸
１０ピストン
１１偏芯軸
１５ピストンピン
１９コンロッド
５０小端部
５１小端孔
５２大端部
５３大端孔
５４円孔部
５５固定孔
５６突起部
５７端面部
５８ロッド部
５９係止孔
６０係止部
６１係止突起部
６３固定溝部
６５ロッキングピン
７０固定平面部
７１係止平面部
７５第１給油孔
７６第２給油孔
７７横油孔
７８油溝
７９連通油孔
８０係止溝
８１固定溝
８２固定板
８３カギ部
８５保持部
８６補助平面部
９０第２係止突起部
９１係止端面
９２固定端面[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a relatively small reciprocating piston compressor used for a household refrigerator or the like.
[0002]
[Prior art]
In recent years, the reciprocating piston compressor has been improved in various ways from the viewpoint of miniaturization and simplification of assembly. In addition, there is a high demand for higher efficiency and lower noise from the market.
[0003]
Conventional reciprocating piston compressors include those disclosed in Japanese Patent Application Laid-Open No. 4-164174 and Japanese Patent Publication No. 5-84837.
[0004]
Hereinafter, a conventional reciprocating piston compressor disclosed in the above-mentioned Japanese Patent Publication No. 5-84837 will be described with reference to FIGS. 16, 17 and 18.
[0005]
16 is a longitudinal sectional view of a conventional reciprocating piston compressor, FIG. 17 is an enlarged view of FIG. 16, an exploded view of a connecting rod and a piston before assembling the reciprocating piston compressor, and FIG. 18 is a large end portion of the connecting rod. FIG.
[0006]
In FIGS. 16, 17, and 18, the motor / compressor unit 1 is supported in the housing 3 by a spring 2. The crankcase 4 serves as a support base for installing the stator 5 of the motor and includes a bearing portion 6 for supporting the crankshaft 7 connecting the rotor 8 of the motor. The crankcase 4 includes a cylinder 9 in which the piston 10 reciprocates. An eccentric shaft 11 is provided at the upper end of the crankshaft 7. A valve plate 17 and a cylinder head 18 that can be manufactured by a known method are attached to the cylinder 9 at the end of the cylinder 9 and on the opposite side of the crankshaft 7. The connecting rod 19 includes a small end portion 20 and a large end portion 30, and connects the piston 10 and the eccentric shaft 11 of the crankshaft 7.
[0007]
The small end portion 20 of the connecting rod 19 includes a small end hole portion 21 and a long first protruding portion 22 extending in a radial direction from the small end hole portion 21, and the first protruding portion 22 defines an arm portion of the connecting rod 19. The hole 21 is connected to the piston 10 by the piston pin 15.
[0008]
The large end portion 30 of the connecting rod 19 includes a large end hole portion 31 having a short second protrusion 32 extending in the radial direction having a vertical groove 33, and the large end hole portion 31 includes an eccentricity of the crankshaft 7. A shaft 11 is inserted.
[0009]
The groove 33 of the large end hole 31 is formed inside the second protrusion 32, and is opposed to and parallel to two surfaces 34, and two internal second end surfaces 35 formed in a V shape. And a vertical recess 36 is provided at the top of the second end surface 35. The end portion 27 of the first protrusion 22 is formed with a surface 24 and two V-shaped first end surfaces 25, and these first end surfaces 25 are completely in contact with the second end surface 35 of the groove 33. It is configured to touch.
[0010]
The operation of the conventional reciprocating piston compressor configured as described above will be described below.
[0011]
With the crankshaft 7 inserted into the bearing 6 of the crankcase 4, the large end hole 31 of the large end 30 of the connecting rod 19 is inserted into the eccentric shaft 11, and the piston pin 15 is inserted into the small end hole 21. By doing so, the piston 10 and the small end portion 20 connected to each other are inserted from the counter crankshaft of the cylinder 9.
[0012]
Thereafter, the end portion 27 of the first protrusion portion 22 of the small end portion 20 is fitted into the groove 33 of the second protrusion portion 32 of the large end portion 30, and the surface 24, the first end surface 25, and the first protrusion of the first protrusion portion 22 are fitted. The surface 34 and the second end surface 35 of the groove 33 of the portion 32 are brought into contact with each other and fixed by a method such as welding. The connecting rod 19 to which the large end portion 30 and the small end portion 20 are fixed compresses the gas in the cylinder 9 by converting the rotation of the crankshaft 7 into the reciprocating motion of the piston 10 and transmitting the force.
[0013]
[Problems to be solved by the invention]
However, in the above-described conventional configuration, the joining of the small end 20 and the large end 30 of the connecting rod 19 is performed by fitting the end 27 and the groove 33, so that the surface 24 of the end 27, the first end surface 25, The surface 34 and the second end surface 35 of the groove 33 need to be finished with very high accuracy, and have a drawback that it is difficult to process.
[0014]
Further, the above-described conventional configuration is such that the axial center of the hole of the large end hole portion 31 is parallel to the surface 34 of the groove 33, the second end surface 35, or the axial center of the small end hole portion 21 and the surface 24 of the end portion 27, If the parallelism with the first end face 25 is slightly deviated, the shafts of the large end hole 31 and the small end hole 21 of the connecting rod 19 are twisted or there is no end face to be defined when a force is applied in the vertical direction, and the vertical direction is fixed. Becomes very unstable, causing the connecting rod 19 to be twisted to the crankshaft 7 and the piston pin 15, increasing the rotational load of the compressor, leading to an increase in noise or vibration and a reduction in efficiency.
[0015]
SUMMARY OF THE INVENTION An object of the present invention is to provide a reciprocating piston compressor that is highly accurate, easy to process and assemble, highly efficient, low noise, and low vibration.
[0016]
Further, in the above-described conventional configuration, the oil supply to the joint portion of the small end portion 20 and the large end portion 30 of the connecting rod 19 relies on the mist-like oil in the housing 3, and there is no positive oil supply. There was a defect that caused deterioration of reliability due to metal wear.
[0017]
Another object of the present invention is to positively supply oil to the joint portion of the connecting rod 19 and improve reliability.
[0018]
[Means for Solving the Problems]
To achieve this object, the present invention is a reciprocating comprising a connecting rod having a small end connected to a piston by a piston pin at a small end hole and a large end connected to an eccentric shaft of the crankshaft by a large end hole. A piston compressor, the large end of the connecting rod has a cylindrical circular hole and a protrusion having a fixed hole communicating with the cylindrical circular hole, and the circular hole is hemispherical or substantially conical in shape at the bottom, It is provided at a depth that does not penetrate through the large end hole from the end face of the projection to the center of the large end hole, the small end has a cylindrical rod portion that is long in the radial direction, and the rod portion is at the end. The locking hole and the tip constitute a hemispherical or substantially conical locking part, and this locking part is loosely fitted or lightly press-fitted into the circular hole part of the protrusion, and the fixing hole and the locking hole are communicated By inserting the locking pin, the locking portion and the circular hole portion are locked, and the small end hole of the small end portion of the connecting rod is The arrangement of the geometric axis of the larger end hole of the end portion is to keep on the same plane.
[0019]
Thereby, processing and assembly of the reciprocating piston compressor are performed with high accuracy, and high efficiency, low noise, and low vibration can be achieved.
[0020]
Further, a flat portion is provided in the cylindrical locking portion of the rod portion and the cylindrical circular hole portion of the protrusion portion.
[0021]
As a result, the reciprocating piston compressor can be easily assembled, the behavior of the locking portion around the axis can be regulated, the connecting rod behavior can be stabilized, and the decrease in efficiency and the increase in noise and vibration can be prevented.
[0022]
Further, an oil hole is provided for communicating the top of the circular hole with the large end hole, and the oil hole is communicated with the oil groove of the eccentric shaft of the crankshaft.
[0023]
Thereby, it is possible to actively supply oil to the joint portion between the small end portion and the large end portion of the connecting rod, reduce metal wear, and improve the reliability of the reciprocating piston compressor.
[0024]
In addition, a locking groove is provided in the cylindrical locking portion of the rod portion, and a fixing groove is provided in the flat portion of the protruding portion, and the locking portion of the rod portion is loosely fitted or lightly press-fitted into the circular hole portion of the protruding portion, By engaging the fixing plate in communication with the locking groove from the fixing groove, the locking part and the circular hole part are locked, and the geometry of the small end hole at the small end of the connecting rod and the large end hole at the large end The arrangement of the target axes is maintained on the same plane.
[0025]
Thereby, fixation with the small end part of a connecting rod and a large end part can be strengthened, a connecting rod behavior can be stabilized, and the fall of efficiency, the increase in a noise, and a vibration can be prevented.
[0026]
In addition, a holding portion having an auxiliary flat surface portion that is joined to the end surface portion of the protruding portion when fitted with the circular hole portion is provided between the rod portion and the locking portion.
[0027]
As a result, the assemblability is improved, the load acting on the auxiliary flat surface portion and the end surface portion is reduced, the connecting rod behavior is stabilized, and the decrease in efficiency, noise and vibration can be prevented.
[0028]
Further, a second locking projection having a locking end surface parallel to the cylindrical axis direction of the small end hole is provided between the rod portion and the locking portion, and the cylindrical shaft of the large end hole is provided at the large end projection. A fixed end surface parallel to the direction is provided, and when the small end portion and the large end portion are connected, the locking end surface and the fixed end surface are joined to define a fitting position between the small end portion and the large end portion.
[0029]
As a result, the assembly can be performed with high accuracy, the connecting rod behavior can be stabilized, and the decrease in efficiency and the increase in noise and vibration can be prevented.
[0030]
DETAILED DESCRIPTION OF THE INVENTION
The present invention is a reciprocating piston compressor comprising a connecting rod having a small end portion connected to a piston by a small end hole by a piston pin and a large end portion connected to an eccentric shaft of a crankshaft by a large end hole. The large end of the connecting rod has a cylindrical circular hole and a protrusion having a fixed hole communicating with the cylindrical hole. The bottom of the circular hole has a hemispherical shape or a substantially conical shape and extends from the end surface of the protrusion. It is provided at a depth that does not penetrate the large end hole toward the center of the large end hole, the small end portion has a cylindrical rod portion that is long in the radial direction, and the rod portion has a locking hole and a tip at the end portion. A hemispherical or substantially conical locking portion is configured, and this locking portion is loosely fitted or lightly press-fitted into the circular hole portion of the projection, and the locking pin is connected to the locking hole by connecting the fixing hole and the locking hole. By inserting, the locking part and the circular hole part are locked, the geometry of the small end hole of the connecting rod small end part and the large end hole of the large end part It is intended to maintain coplanar the arrangement of the specific axis.
[0031]
When a load is applied to the connecting rod from any direction during the operation of the compressor, the tip of the small end semispherical or substantially conical locking portion is the large end circular hole or hemispherical or substantially circular. Surface contact is made at the bottom surface of the spindle, and the load is dispersed so that the concentrated load at the edge portion and the like is not received. Also, when connecting the large end to the small end, the tip of the locking portion at the large end has a hemispherical shape or a substantially conical shape, and there is no edge and it is easy to make a circular hole at the small end. Can be fitted. Furthermore, when the locking pin is inserted into the locking hole at the small end and the fixing hole at the large end, and the two are connected, the locking pin is self-flexible so that the locking pin is connected to the small end hole and the large end at the small end. It absorbs the slight shaft runout of the large end hole of the part and stabilizes itself by correcting itself so that the small end hole and the large end hole are aligned. In addition, since the rod portion at the small end and the circular hole portion at the large end are cylindrical, high-precision processing can be easily performed.
[0032]
This prevents an increase in rotational load due to twisting or twisting during assembly or operation of the compressor.
[0033]
Further, a flat portion is provided in the cylindrical locking portion of the rod portion and the cylindrical circular hole portion of the protrusion portion.
[0034]
When the locking portion of the small end portion is fitted into the circular hole portion of the large end portion, the flat portion of the locking portion and the flat portion of the circular hole portion are fitted and positioned, The fixed holes of the circular holes are almost the same, and it is possible to easily assemble without aligning the holes when inserting the locking pin, and the behavior of the locking part around the axis is prevented. The behavior will be stable.
[0035]
Further, an oil hole is provided for communicating the top of the circular hole with the large end hole, and the oil hole is communicated with the oil groove of the eccentric shaft of the crankshaft.
[0036]
Then, during the operation of the compressor, positive oiling is performed on the locking portion at the small end portion and the circular hole portion at the large end portion, and wear due to metal contact is reduced.
[0037]
In addition, a locking groove is provided in the cylindrical locking portion of the rod portion, and a fixing groove is provided in the flat portion of the protruding portion, and the locking portion of the rod portion is loosely fitted or lightly press-fitted into the circular hole portion of the protruding portion, By engaging the fixing plate in communication with the locking groove from the fixing groove, the locking part and the circular hole part are locked, and the geometry of the small end hole at the small end of the connecting rod and the large end hole at the large end The arrangement of the target axes is maintained on the same plane.
[0038]
Then, the connecting rod behavior is stabilized by firmly fixing the large end portion and the small end portion with the fixing plate.
[0039]
Further, a holding portion having an auxiliary flat surface portion that is joined to the end surface portion of the protruding portion when fitted with the circular hole portion is provided between the rod portion and the locking portion.
[0040]
And the fitting allowance to the circular hole part of a locking part is prescribed | regulated, while an assembly property improves, the dispersion | distribution of the load received to the joining surface of an end surface part and an auxiliary plane part can be aimed at, and a connecting rod behavior will be stabilized. .
[0041]
Further, a second locking projection having a locking end surface parallel to the cylindrical axis direction of the small end hole is provided between the rod portion and the locking portion, and the cylindrical shaft of the large end hole is provided at the large end projection. A fixed end surface parallel to the direction is provided, and when the small end portion and the large end portion are connected, the locking end surface and the fixed end surface are joined to define a fitting position between the small end portion and the large end portion.
[0042]
When the locking portion is fitted into the circular hole portion, the locking end surface and the fixed end surface are joined to define the cylindrical portion position of the locking portion and the fitting margin, and the locking pin is inserted into the locking hole and the fixing hole. There is no need to finely adjust the hole position when inserting the rod, and it is easy to assemble. Will be stable.
[0043]
【Example】
Embodiments of a reciprocating piston compressor according to the present invention will be described below with reference to the drawings. In addition, about the same structure as the past, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.
[0044]
Example 1
1 is a longitudinal sectional view of a reciprocating piston compressor according to a first embodiment of the present invention. 2 is an enlarged view of FIG. 1, an exploded view of the connecting rod and the piston before assembling the reciprocating piston compressor, FIG. 3 is a plan view before assembling the connecting rod of FIG. 1, and FIG. It is a partial longitudinal cross-sectional view at the time of an assembly.
[0045]
In FIG. 1, reference numeral 19 denotes a connecting rod, one end of which is connected to the piston 10 by a piston 15 loosely fitted in the small end hole 51 of the small end portion 50, and the other end is a large end hole 53 of the large end portion 52. 7 is loosely fitted and connected to the eccentric shaft 11.
[0046]
In FIG. 2, the piston 10, the piston pin 15, and the small end portion 50 are inserted from the side opposite to the crankshaft 7 of the cylinder 9, and the large end portion 52 of the connecting rod 19 is vertically above the eccentric shaft 11 of the crankshaft 7. Is inserted from.
[0047]
The large end portion 52 of the connecting rod 19 has a circular hole portion 54 in the circumferential direction and a protrusion 56 having a fixing hole 55 that penetrates the circular hole portion 54. The circular hole portion 54 forms a right angle with the large end hole 53 and is processed to a depth that does not penetrate the large end hole 53 from the end surface portion 57 of the protrusion 56. In the small end portion 50, a rod portion 58 that forms a right angle with the small end hole 51 extends in the circumferential direction, and a locking portion 60 having a locking hole 59 is provided at the tip thereof.
[0048]
3 and 4, reference numeral 61 denotes a front end of the locking portion 60, which is a locking protrusion processed into a hemispherical shape or a substantially conical shape. Reference numeral 62 denotes a locking top of the locking projection 61, which is processed into a round shape. 63 is a fixed groove portion processed into a hemispherical shape or a substantially conical shape of the circular hole portion 54, and 64 is a groove top portion of the fixed groove portion.
[0049]
After inserting the locking portion 60 into the circular hole portion 54, the locking pin 65 is inserted into the locking hole 59 of the locking portion 60 of the small end portion 50 from the fixing hole 55 of the projection portion 56 of the large end portion 52. The small end 50 and the large end 52 of the connecting rod 19 are connected and fixed.
[0050]
The operation of the above configuration will be described below.
Since the circular hole portion 54 is a connecting portion of the small end portion 50 and both of the locking portions 60 are cylindrical, processing is easy and dimensional accuracy is easily obtained.
[0051]
When the engaging portion 60 is loosely fitted or lightly press-fitted into the circular hole portion 54, the engaging protrusion 62, which is the tip of the engaging portion 60, is hemispherical or substantially conical, so that it smoothly enters the circular hole portion 54. It is inserted.
[0052]
Further, since both the locking portion 60 and the circular hole portion 54 are cylindrical, they can be slightly swung around the cylindrical axis, and the cylindrical shafts of the small end hole 51 and the large end hole 53 are not easily twisted during assembly. Nothing will happen.
[0053]
Then, after engaging the locking portion 60 with the circular hole portion 60 into the circular hole portion 54, the locking top portion 62 is processed into a round shape, so that the clearance with the groove top portion 64 is left slightly. At this time, a small amount of assembly oil is held in this clearance.
[0054]
Next, when the locking pin 65 is inserted into the locking hole 59 and the fixing hole 55, the locking pin 65 causes twisting of the cylindrical shafts of the small end hole 51 and the large end hole 53 that are slightly twisted when fitted due to its own deformation. The locking portion 60 is fixed to the circular hole portion 54 by correcting in the same axial direction.
[0055]
Further, when the cylindrical shaft of the small end hole 51 and the large end hole 53 is twisted due to a compression load or the like during the operation of the compressor, the locking pin 65 is slightly deformed by this load and the balance of the compressor mechanism is increased. Is stable where it is good.
[0056]
Further, since the connecting rod 19 converts the rotational behavior into the translational behavior, during operation of the compressor, the large end portion 52 is moved to the small end portion 50 via the locking portion 60, and the front, rear, left and right shown in FIG. The force in all directions such as the direction and the up and down direction shown in FIG. 4 acts on the locking portion 60 and the circular hole portion 54. At this time, since the tip of the locking portion 60 is processed into a hemispherical shape or a substantially conical shape, a surface facing in any direction is formed. For this reason, the cylindrical shafts of the small end portion 50 and the large end portion 52 are stabilized in the same direction during the operation of the compressor, and the rotational force of the crankshaft 7 is hardly lost at the locking portion 60, and the piston pin 15 can transmit the force.
[0057]
As described above, in the reciprocating piston compressor of this embodiment, the large end portion 52 of the connecting rod 19 has the cylindrical circular hole portion 54 and the protruding portion 56 having the fixing hole 55 communicating with the cylindrical circular hole portion 54. The bottom shape is hemispherical or substantially conical, and is provided at a depth that does not penetrate the large end hole 53 from the end surface portion 57 of the projection 56 toward the center of the large end hole 53, and the small end portion 50 has a radius. The rod portion 58 has a cylindrical rod portion 58 that is long in the direction. The rod portion 58 forms a locking hole 59 at the end and a locking portion 60 having a hemispherical or substantially conical shape at the tip. Is loosely fitted or lightly press-fitted into the circular hole portion 54 of the projection 56, and the locking hole 59 and the circular hole portion 54 are engaged by inserting the locking pin 65 through the fixing hole 55 and the locking hole 59. The geometric axis of the small end hole 51 in the small end 50 of the connecting rod 19 and the large end hole 53 in the large end 52 is fixed. The device is maintained on the same plane, and it is easy to process and assemble with high accuracy. The efficiency decreases due to an increase in rotational load caused by the twist of the cylindrical shaft of the small end hole 51 and the large end hole 53, and the small end. It is possible to prevent an increase in noise and vibration due to abnormal twisting of the hole 51 and the piston pin 15, the large end hole 53 and the eccentric shaft 11, the locking portion 60 and the circular hole portion 54, and the like.
[0058]
(Example 2)
5 is a plan view of the reciprocating piston compressor according to the second embodiment of the present invention before the assembly of the connecting rod, and FIG. 6 is a view of the large end A before the assembly from the A arrow of FIG. FIG. 7 is a partial longitudinal sectional view when the connecting rod is assembled. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
[0059]
5, 6, and 7, reference numeral 70 denotes a fixed plane portion provided in the cylindrical axis direction of the cylindrical circular hole portion 54 of the large end portion 52. Since the fixed groove portion 63 is the fixed flat surface portion 70, the fixed groove portion 63 is processed by making the step diameter smaller than the cylindrical diameter of the circular hole portion 54. Reference numeral 71 denotes a locking flat portion provided in the cylindrical axis direction of the cylindrical locking portion 60 of the small end portion 50. Similarly to the fixed groove 63, the locking projection 61 is a locking flat surface portion 71, and is processed with a one-step diameter smaller than the cylindrical diameter of the locking portion 60.
[0060]
The operation of the above configuration will be described below.
When the locking portion 60 is fitted into the circular hole portion 54, the locking flat surface portion 71 and the fixed flat surface portion 70 act as a kind of positioning guider, and the locking hole 59 that is slightly shifted at the same time as the locking is fixed. The holes 55 coincide with each other with accuracy, and the locking pin 65 can be easily inserted.
[0061]
Further, the behavior of the locking portion 60 about the axis is restricted by the joining of the locking plane 70 and the fixed plane 71, and the behavior of the connecting rod 19 is stabilized.
[0062]
As described above, in the reciprocating piston compressor of this embodiment, the locking end surface portion 71 is provided in the cylindrical locking portion 60 of the rod portion 58, and the fixed flat surface portion 70 is provided in the cylindrical circular hole portion 54 of the protruding portion 56. When the connecting rod 19 is assembled, the locking portion 60 is fitted into the circular hole portion 54, and at the same time the positions of the locking hole 59 and the fixing hole 55 are accurately matched, and the locking pin 65 is inserted. Easy to perform and easy to assemble.
[0063]
Further, the behavior around the axis of the locking portion 60 is restricted, and the connecting rod behavior can be stabilized.
[0064]
In this embodiment, the locking hole 59 is provided from the locking flat part 71 and the fixing flat part 70 is provided from the fixing hole 55, but these flat parts are located at any position on the periphery of the cylindrical shape. The same effect can be obtained with wax.
[0065]
(Example 3)
FIG. 8 is a partial longitudinal sectional view of the connecting rod and the eccentric shaft during the suction stroke of the reciprocating piston compressor according to the third embodiment of the present invention, and FIG. 9 is a partial longitudinal sectional view of the connecting rod and the eccentric shaft during the compression stroke. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
[0066]
8 and 9, reference numeral 75 denotes a first oil supply hole provided in the crankshaft 7 and communicates with a second oil supply hole 76 provided in the eccentric shaft 11. The second oil supply hole 76 is opened at the upper end surface of the eccentric shaft 11 and a lateral oil hole 77 communicating with the oil groove 78 on the outer periphery of the eccentric shaft 11 is provided from the middle of the second oil supply hole 76 in the radial direction. ing. The lateral oil hole 77 and the oil groove 78 are directed to the axial direction side of the crankshaft 7. A communication oil hole 79 communicates from the groove top 64 of the fixed groove 63 to the large end hole 53.
[0067]
The operation of the above configuration will be described below.
The point shown in FIG. 8, FIG. 9 represents the oil grain, and the arrow has shown the flow of oil.
[0068]
During the intake stroke of the compressor, the lubricating oil (not shown) accumulated at the bottom of the housing 3 is supplied to the second oil supply by the centrifugal pump action of the first oil supply hole 75 of the crankshaft 7 as the compressor rotates. It is pushed up to the hole 76. The oil particles are guided from the second oil supply hole 76 to the oil groove 78 provided on the outer periphery of the eccentric shaft 11 by the centrifugal force generated by the rotation of the eccentric shaft 11. Some oil particles are discharged from above the eccentric shaft 11 into the housing 3.
[0069]
Therefore, as shown in FIG. 8, during the intake stroke of the compressor, the oil groove 78 is positioned in the axial direction of the crankshaft 7, so that the communication provided in the oil groove 78 and the large end 52 of the connecting rod 19 is provided. The oil hole 79 communicates. Further, the small end portion 50 is pulled toward the crankshaft 7 side, and the large end portion 52 is pulled toward the crankshaft 7 side. As a result, a slight gap is generated between the locking projection 61 and the fixed groove 63, and the oil particles reaching the oil groove 78 by centrifugal force pass through the communication oil hole 79 without losing its inertial force. It is guided to a slight gap between the locking projection 61 and the fixing groove 63.
[0070]
Further, during the compression stroke as shown in FIG. 9, the oil groove 78 and the communication oil hole 79 do not communicate with each other, and a compression load is received from the small end portion 50, so that the locking projection 61 and the fixed groove 63 are pressed against each other. It will be. As a result, the oil particles guided to the gap during the suction stroke are pressed, flow backward through the locking pin 65 or the communication oil hole 79 from the slight gap, and are discharged into the housing 3 from the upper and lower portions of the eccentric shaft 11. . Further, the oil particles guided to the oil groove 78 through the lateral oil hole 77 are supplied as lubricating oil for the large end hole 53 and the eccentric shaft 11.
[0071]
From this, the lubricating oil is evenly supplied to the locking projection 61 and the fixing groove 63 which are the connecting portions of the connecting rod 19, and the lubricating oil circulates to act as a cooling effect around the connecting portion, and slides. Loss can be reduced and wear due to metal contact can be prevented.
[0072]
As described above, the reciprocating piston compressor of the present embodiment is provided with the communication oil hole 79 communicating with the large end hole 53 and the groove top portion 64 of the fixed groove portion 63, and also with the oil groove 78 of the eccentric shaft 11 and the communication oil hole. 79 is configured to communicate with each other, so that the lubricating oil can be positively supplied to the locking projection 61 and the fixing groove 63 which are the connecting portions of the connecting rod 19. As a result, an increase in sliding loss and wear due to metal contact can be prevented.
[0073]
In the present embodiment, the oil groove 78 and the communication oil hole 79 communicate with each other during the intake stroke. However, the oil groove 78 and the communication oil hole 79 may communicate with each other during the other stroke, or the same effect can be obtained.
[0074]
Example 4
10 is a plan view of the reciprocating piston compressor according to the fourth embodiment of the present invention before assembly of the connecting rod, and FIG. 11 is a partial longitudinal sectional view of the connecting rod of FIG. 10 when assembled. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
[0075]
10 and 11, reference numeral 80 denotes a locking groove 80 provided on the outer periphery of the cylindrical locking portion 60 of the small end portion 50, and 81 denotes a fixing groove provided on the projection 56 of the large end portion 52. It is. The fixing groove 81 is partially communicated with the circular hole portion 54. Reference numeral 82 denotes a fixing plate for fixing the locking portion 60 to the circular hole portion 54, and the distal end of the fixing plate 82 has a key portion constituting a protrusion of the key.
[0076]
The operation of the above configuration will be described below.
When the locking portion 60 is fitted into the circular hole portion 54, the locking groove 80 and the fixing groove 81 overlap each other. Thereafter, the fixing plate 82 is inserted from the fixing groove 81 to the locking groove 80 and inserted, and the key portion 83 that is the tip of the fixing plate 82 is fitted into the end surface of the protrusion 56. Thereby, the locking part 60 is pressed against the bottom part of the circular hole part 54 and fixed.
[0077]
Therefore, almost the load received by the locking projection 61 and the fixing groove 63 is received by the fixing plate 82, so that the connecting rod 19 can be firmly connected, and the connecting rod behavior is stabilized.
[0078]
As described above, the reciprocating piston compressor according to the present embodiment includes the locking groove 80 on the outer periphery of the locking portion 60 of the small end portion 50 and the fixed groove communicating with the circular hole portion 54 on the protrusion 56 of the large end portion 52. 81, and after engaging the locking portion 60 into the circular hole portion 54, a fixing plate 82 having a key portion 83 at the tip thereof is connected to the locking groove 80 from the fixing groove 81, and is inserted into the large end portion 50. By adopting a configuration in which the end portion 52 is connected and fixed, the locking portion 60 is firmly fixed to the circular hole portion 54, and most of the load acting on the connecting rod 19 during the operation of the compressor is supported by the fixing plate 82, so that the connecting rod behavior is improved. It can be stabilized.
[0079]
(Example 5)
12 is a plan view of a reciprocating piston compressor according to a fifth embodiment of the present invention before assembly of a connecting rod, and FIG. 13 is a partial longitudinal sectional view of the connecting rod of FIG. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
[0080]
12 and 13, reference numeral 85 denotes the rod portion 58 of the small end portion 50 having the plane opposite to the plane of the end surface portion 57 of the projection portion 56 of the large end portion 52 and the locking portion 60. It is the holding | maintenance part provided in between.
[0081]
The operation of the above configuration will be described below.
When the engaging portion 60 is fitted into the circular hole portion 54, the auxiliary flat surface portion 86 is joined to the end surface portion 57. Thereby, a fitting margin can be defined in the circular hole portion 54 of the locking portion 60, and the connecting pin 19 can be assembled by easily inserting the locking pin 65 into the locking hole 59 and the fixing hole 55.
[0082]
Further, the load received during the compression stroke of the compressor can be received by the auxiliary flat surface portion 86, and the behavior of the connecting rod 19 can be stabilized.
[0083]
As described above, the reciprocating piston compressor of this embodiment is configured such that the holding portion 85 having the auxiliary flat surface portion 86 facing the end surface portion 57 of the projection portion 56 is provided between the locking portion 60 and the rod portion 58. By doing so, the allowance for fitting the locking portion 60 into the circular hole portion 54 can be defined, the connecting rod 19 can be assembled easily, and the load during the compression stroke is received by the auxiliary plane portion, thereby connecting rod 19 The behavior of can be stabilized.
[0084]
In this embodiment, the locking projection 61 and the fixing groove 63 are provided, but the same effect can be obtained without them.
[0085]
(Example 6)
FIG. 14 is a plan view of the reciprocating piston compressor according to the sixth embodiment of the present invention before assembly of the connecting rod, and FIG. 15 is a partial longitudinal sectional view of the connecting rod of FIG. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
[0086]
14 and 15, reference numeral 90 denotes a second locking projection provided between the rod portion 58 having the locking end surface 91 provided parallel to the cylindrical axis of the small end hole 51 and the locking portion 60. And 92 is a fixed end face of the projection 56 provided parallel to the cylindrical axis of the large end hole 53 facing the locking end face 91.
[0087]
The operation of the above configuration will be described below.
When the locking portion 60 is fitted into the circular hole portion 54, the locking end surface 91 and the fixed end surface 92 are joined to define the fitting margin of the locking portion 60 and the position in the left-right direction. And the position of the fixing hole 55 coincide with each other with high accuracy. Thereby, the locking pin 65 can be easily inserted into the locking hole 59 and the fixing hole 55, and the connecting rod 19 can be easily assembled.
[0088]
Further, because of the second locking projection 91, the small end 50 and the large end 52 are prevented from being displaced around the axis of the locking portion 60 or in the left-right direction during operation of the compressor, and the connecting rod 19 is connected. And the behavior of the connecting rod 19 can be stabilized.
[0089]
As described above, the reciprocating piston compressor of the present embodiment is provided with the second locking projection portion having the locking end surface 91 parallel to the cylindrical axis of the small end hole 51 between the locking portion 60 and the rod portion 58. In addition, the fixed end surface 92 parallel to the cylindrical axis of the large end hole 53 is provided in the protrusion 56 so that the engaging end surface 91 and the fixed end surface are fitted when the engaging portion 60 and the circular hole portion 54 are fitted. 92 is joined, the locking hole 59 and the fixing hole 55 can be made to coincide with each other with high accuracy, and assembly can be easily performed. Further, the fixing of the locking portion 60 between the small end portion 50 and the large end portion 52 around the axis and in the left-right direction can be strengthened, and the behavior of the connecting rod 19 can be stabilized.
[0090]
In this embodiment, the locking projection 61 and the fixing groove 63 are provided, but the same effect can be obtained without them.
[0091]
【The invention's effect】
As described above, the present invention is a reciprocating piston comprising a connecting rod having a small end portion connected to a piston by a small end hole by a piston pin and a large end portion connected to an eccentric shaft of the crankshaft by a large end hole. The large end portion of the connecting rod has a cylindrical circular hole portion and a protrusion portion having a fixed hole communicating therewith, and the circular hole portion has a hemispherical shape or a substantially conical shape, and has a protrusion shape. It is provided at a depth that does not penetrate the large end hole from the end face of the section toward the center of the large end hole, and the small end section has a cylindrical rod section that is long in the radial direction, and the rod section is engaged with the end section. The stop hole and the tip constitute a hemispherical or substantially conical locking part, and the locking part is loosely fitted or lightly press-fitted into the circular hole part of the protrusion, and the fixing hole and the locking hole are communicated with each other. By inserting the locking pin, the locking part and the circular hole part are locked, and the small end hole and the large end hole of the connecting rod are large. By maintaining the geometric axis arrangement of the large end holes on the same plane, high-precision processing and assembly can be facilitated, and twisting of the small and large end holes and twisting of fittings It is possible to prevent a decrease in efficiency due to an increase in rotational load, and an increase in noise and vibration.
[0092]
In addition, the cylindrical locking part of the rod part and the cylindrical circular hole part of the protrusion part are provided with a flat part, so that the positioning when the locking part is fitted into the circular hole part can be performed, and the connecting rod is assembled. Can be performed with high accuracy, and the axis of the locking portion is fixed, so that it is possible to prevent a decrease in efficiency and an increase in noise and vibration due to an increase in rotational load.
[0093]
In addition, an oil hole that connects the top of the circular hole portion and the large end hole is provided, and the oil hole and the oil groove of the eccentric shaft of the crankshaft are connected to each other, thereby positively supplying oil to the locking portion and the circular hole portion. Thus, wear due to metal contact can be prevented, and reliability can be improved.
[0094]
In addition, a locking groove is provided in the cylindrical locking portion of the rod portion, and a fixing groove is provided in the flat portion of the protruding portion, and the locking portion of the rod portion is loosely fitted or lightly press-fitted into the circular hole portion of the protruding portion, By engaging the fixing plate in communication with the locking groove from the fixing groove, the locking part and the circular hole part are locked, and the geometry of the small end hole at the small end of the connecting rod and the large end hole at the large end By maintaining the arrangement of the target shaft on the same plane, the locking portion and the circular hole portion can be firmly connected with the fixing plate, and the behavior of the connecting rod can be stabilized. Thereby, the fall of the efficiency by the increase in the rotation load of the compressor resulting from loose connection etc., and the increase in noise and vibration can be reduced.
[0095]
In addition, by providing a holding portion having an auxiliary flat surface portion that joins the end surface portion of the protruding portion when fitted to the circular hole portion between the rod portion and the locking portion, the locking portion and the circular hole portion The connection is efficiently performed, and the load acting at the time of compression can be dispersed between the auxiliary plane portion and the end surface portion, and the behavior of the connecting rod can be stabilized. Thereby, the fall of the efficiency by the increase in the rotation load of a compressor, and the increase in a noise and a vibration can be prevented.
[0096]
Further, a second locking projection having a locking end surface parallel to the cylindrical axis direction of the small end hole is provided between the rod portion and the locking portion, and the cylindrical shaft of the large end hole is provided at the large end projection. A fixed end surface parallel to the direction is provided, and when the small end and the large end are connected, the locking end surface and the fixed end surface are joined, and the fitting position between the small end and the large end is defined, thereby locking with high precision. The connecting portion and the circular hole portion can be connected to improve the assemblability, and the connecting rod's locking portion can be prevented from being displaced around the axis and in the lateral direction, thereby stabilizing the behavior of the connecting rod. Thereby, it is possible to prevent a decrease in efficiency and an increase in noise and vibration due to an increase in rotational load.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a reciprocating piston compressor according to a first embodiment of the present invention.
FIG. 2 is an exploded view of a connecting rod and a piston before assembling the reciprocating piston compressor of the reciprocating piston of the reciprocating piston compressor of the same embodiment.
FIG. 3 is a plan view of the reciprocating piston compressor of the same embodiment before connecting rods are assembled.
FIG. 4 is a partial longitudinal sectional view of the reciprocating piston compressor of the same embodiment when the connecting rod is assembled.
FIG. 5 is a plan view of a reciprocating piston compressor according to a second embodiment of the present invention before assembling a connecting rod.
FIG. 6 is a view of the large end portion A as viewed in the direction of the arrow A before assembling the connecting rod of the reciprocating piston compressor of the second embodiment of the present invention.
7 is a partial longitudinal cross-sectional view of the reciprocating piston compressor according to the second embodiment of the present invention during assembly of the connecting rod. FIG.
FIG. 8 is a partial longitudinal sectional view of a connecting rod and an eccentric shaft during a suction stroke of a reciprocating piston compressor according to a third embodiment of the present invention.
FIG. 9 is a partial longitudinal sectional view of a connecting rod and an eccentric shaft during a compression stroke of a reciprocating piston compressor according to a third embodiment of the present invention.
FIG. 10 is a plan view of a reciprocating piston compressor according to a fourth embodiment of the present invention before assembly of a connecting rod according to a fourth embodiment.
FIG. 11 is a partial vertical cross-sectional view of the reciprocating piston compressor according to the fourth embodiment of the present invention during assembly of the connecting rod.
12 is a plan view of a reciprocating piston compressor according to a fifth embodiment of the present invention before assembly of a connecting rod according to a fifth embodiment. FIG.
FIG. 13 is a partial longitudinal sectional view of the reciprocating piston compressor according to the fifth embodiment of the present invention during assembly of the connecting rod.
14 is a plan view of a reciprocating piston compressor according to a sixth embodiment of the present invention before assembly of a connecting rod according to Embodiment 6. FIG.
FIG. 15 is a partial longitudinal sectional view of the reciprocating piston compressor of the present invention when the connecting rod of the sixth embodiment is assembled.
FIG. 16 is a longitudinal sectional view of a conventional reciprocating piston compressor.
FIG. 17 is an exploded view of a connecting rod and a piston before assembling a conventional reciprocating piston compressor.
FIG. 18 is an exploded plan view of a large end and a small end of a connecting rod of a conventional reciprocating piston compressor.
[Explanation of symbols]
3 Housing
7 Crankshaft
10 piston
11 Eccentric shaft
15 Piston pin
19 Connecting rod
50 Small end
51 Small end hole
52 Large end
53 Large end hole
54 Round hole
55 Fixing hole
56 Projection
57 End face
58 Rod part
59 Locking hole
60 Locking part
61 Locking protrusion
63 Fixed groove
65 Locking pin
70 Fixed plane part
71 Locking plane part
75 1st oil hole
76 Second oil hole
77 Horizontal oil hole
78 Oil Groove
79 Communication hole
80 Locking groove
81 Fixed groove
82 Fixed plate
83 Key
85 Holding part
86 Auxiliary plane
90 Second locking projection
91 Locking end face
92 Fixed end face

Claims

A reciprocating piston compressor comprising a connecting rod having a small end connected to a piston by a small end hole by a piston pin and a large end connected to an eccentric shaft of the crankshaft by a large end hole, The end portion has a cylindrical circular hole portion and a protruding portion having a fixing hole communicating with the cylindrical hole portion. The circular hole portion has a hemispherical shape or a substantially conical shape in the bottom shape, and extends from the end surface portion of the protruding portion to the large end hole. It is provided at a depth that does not penetrate the large end hole in the center direction, and the small end has a cylindrical rod portion that is long in the radial direction. Consists of a conical locking portion, and this locking portion is loosely fitted or lightly press-fitted into the circular hole portion of the projection, and the locking pin is connected to the locking hole to insert a locking pin The locking portion and the circular hole portion are locked, and the geometric axis of the small end hole of the connecting rod and the large end hole of the large end portion is arranged. Reciprocating piston compressor and maintains the coplanar.

2. A reciprocating piston compressor according to claim 1, wherein a flat portion is provided in the cylindrical locking portion of the rod portion and the cylindrical circular hole portion of the projection portion.

2. A reciprocating piston compressor according to claim 1, wherein an oil hole is provided for communicating the top of the circular hole and the large end hole, and the oil hole is communicated with an oil groove of an eccentric shaft of the crankshaft.

A locking groove is provided in the cylindrical locking portion of the rod portion, and a fixing groove is provided in the flat portion of the protruding portion. The locking portion of the rod portion is loosely fitted or lightly press-fitted into the circular hole portion of the protruding portion, and the fixing groove. The locking plate and the circular hole are locked by inserting the fixing plate in communication with the locking groove, and the geometric axis of the small end hole of the connecting rod and the large end hole of the large end The reciprocating piston compressor according to claim 1, wherein the arrangement is maintained on the same plane.

2. The reciprocating piston compression according to claim 1, wherein a holding part having an auxiliary flat part joined to the end face part of the projection part when fitting with the circular hole part is provided between the rod part and the locking part. Machine.

A second locking projection having a locking end surface parallel to the cylindrical axis direction of the small end hole is provided between the rod portion and the locking portion, and the large end protruding portion is arranged in the cylindrical axis direction of the large end hole. 2. A parallel fixed end face is provided, and the engaging end face and the fixed end face are joined when the small end portion and the large end portion are connected, and the fitting position of the small end portion and the large end portion is defined. The reciprocating piston compressor described.