JP2004092396A - Vane pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vane pump capable of suppressing the vibration and noise resulting from the variation in an air bubble content rate. <P>SOLUTION: In an side plate 50, there is formed a notch 52 for communicating a vane chamber 5 with a discharge port 4 in the pressure transition process from a suction process into a discharge process. The vane pump 1 having the pressure transition process from the suction process into the discharge process of the vane chamber 5 in a cam is provided with a pressure introducing passage 10 for connecting the vane chamber 5 with the discharge port 4. The pressure introducing passage 10 is formed to communicate to the vane chamber 5 to and from the notch 52. <P>COPYRIGHT: (C)2004,JPO

Description

ここで、Ｐ_ｖ：ベーン室圧力、Ｋ_ｅｃ：作動油の等価体積弾性係数、Ｖ_ｖ：べーン室容積、Ｑ_ｃ：カム形状に基づくベーン室容積変化による見かけ上の流量、Ｑ_ｐ１，Ｑ_ｐ２：吸込みおよび吐出ポートから流入する流量、Ｑ_１：ベーン室からの漏れ流量とする。
【０００６】
【数２】

ここで、Ｋ_ｆｍ：作動油の体積弾性係数、Ｋ_ａ：空気の体積弾性係数、Ｘ_ｏ：気泡混入率とする。
【０００７】
つまり、圧力が低いほど等価体積弾性係数が小さく、圧力が上昇すると急激に等価体積弾性係数が増大する特性を有する。従ってこの特性を圧力変化速度の式に適用すると、気泡混入率が大きな場合、圧力が低い時はベーン室への流入流量が多くないと昇圧速度を確保できないが、圧力が上昇してくると供給流量を少なくしないと昇圧速度が急激に上昇することになる。
【０００８】
従来のポートからの流量調整にノッチを用いる方法では、圧力遷移行程でノッチ開口面積が次第に増大するため、ベーン室への供給流量も次第に増大する。このため、気泡混入率の大きな条件では、振動騒音の低減が困難であった。
【０００９】
また、カム形状の変更で予圧縮量を増やした場合、気泡混入率が低下した条件では圧力の変化速度が大きくなりすぎて閉じ込み現象を発生し、種々の気泡混入率に対応することが困難であり、ベーンポンプの振動や騒音の原因になるという問題点があった。
【００１０】
本発明は上記の問題点に鑑みてなされたものであり、気泡含有率の変動に起因した振動や騒音を抑えられるベーンポンプを提供することを目的とする。
【００１１】
【課題を解決するための手段】
第１の発明は、回転するロータから摺動可能に突出する複数のベーンと、各ベーンの外周端部を摺接させてベーン室を画成するカムと、各ベーンの側端部を摺接させてベーン室を画成するサイドプレートとを備え、サイドプレートにロータの回転に伴ってベーン室が拡がる吸込行程でベーン室に作動流体を流入させる吸込ポートと、ロータの回転に伴ってベーン室が収縮する吐出行程でベーン室から作動流体を流出させる吐出ポートとを形成するベーンポンプに適用する。
【００１２】
そして、ベーン室が吸込行程から吐出行程に至る圧力遷移行程でベーン室と吐出ポートを結ぶ圧力導入路を備えたことを特徴とするものとした。
【００１３】
第２の発明は、第１の発明において、サイドプレートに圧力遷移行程で前記ベーン室を吐出ポートに連通するノッチを形成し、圧力導入路を通ってベーン室に流入する作動流体をノッチを通ってベーン室に流入する作動流体に衝突させる構成としたことを特徴とするものとした。
【００１４】
第３の発明は、第１または第２の発明において、圧力導入路としてサイドプレートに開口し吐出ポートからの圧力を導く導入孔を形成し、この導入孔にオリフィスを形成したことを特徴とするものとした。
【００１５】
第４の発明は、第１または第２の発明において、圧力導入路としてサイドプレートに開口し吐出ポートからの圧力を導く導入孔を形成し、ロータに各ベーン間に位置して開口する凹部を形成し、この凹部によって導入孔を所定のタイミングで開く構成としたことを特徴とするものとした。
【００１６】
第５の発明は、第１または第２の発明において、圧力導入路としてサイドプレートに開口し吐出ポートからの圧力を導く導入溝を形成し、ロータに各ベーン間に位置して開口する凹部を形成し、この凹部によって導入溝を所定のタイミングで開く構成としたことを特徴とするものとした。
【００１７】
第６の発明は、第１または第２の発明において、ロータに各ベーンを摺動可能に収めるスリットを形成し、各スリットに吐出ポートからの圧力を導く背圧溝を備え、圧力導入路としてロータに各スリットとベーン室を結ぶ導入孔を形成し、各スリットで摺動するベーンによってこの導入孔を所定のタイミングで開く構成としたことを特徴とするものとした。
【００１８】
【発明の作用および効果】
第１の発明によると、圧力遷移行程で吐出ポートの圧力が圧力導入路を介してベーン室に導かれ、気泡含有率が増加した状態でも圧力遷移行程で圧力上昇が十分に行われ、気泡含有率の変動に起因したベーンポンプの振動や騒音を抑えられるとともに、ベーンポンプの圧力脈動を抑えられる。
【００１９】
ロータの回転速度が高まり、ベーン室の圧力が高まると、圧力導入路からの供給油量は圧力導入路の前後差圧の低下に伴って減少するため、圧力遷移行程でベーン室の圧力が急激に上昇することを回避し、ベーンポンプの振動や騒音を有効に抑えられる。
【００２０】
第２の発明によると、圧力導入路を通ってベーン室に流入する作動油がノッチを通ってベーン室に流入する作動油に衝突することにより、圧力導入路から噴出する作動油の流れを拡散する。これにより、圧力導入路からの噴流に発生するキャビテーション気泡が一箇所に集中して衝突することが回避され、その表面に壊食が生じることを防止できる。
【００２１】
第３の発明によると、オリフィスの開口径を任意に設定し、圧力遷移行程でベーン室の圧力上昇速度を略一定にすることにより、ベーンポンプの騒音を有効に低減できる。また、オリフィスを介して作動油が吐出ポートからベーン室へ急激に逆流することが抑えられ、ベーンポンプの圧力脈動を低減できる。
【００２２】
さらに、オリフィスの通過流量は油温の影響を受け難いため、広い温度範囲で安定した性能が得られる。
【００２３】
第４の発明によると、導入孔が所定のタイミングで開かれることにより、ロータの高回転時に圧力遷移行程の終了直前でベーン室の圧力が急激に上昇することを回避し、ベーンポンプの振動や騒音を有効に抑えられる。
【００２４】
第５の発明によると、導入溝が所定のタイミングで開かれることにより、ロータの高回転時に圧力遷移行程の終了直前でベーン室の圧力が急激に上昇することを回避し、ベーンポンプの振動や騒音を有効に抑えられる。
【００２５】
第６の発明によると、導入孔がベーンを介して所定のタイミングで開かれることにより、ロータの高回転時に圧力遷移行程の終了直前でベーン室の圧力が急激に上昇することを回避し、ベーンポンプの振動や騒音を有効に抑えられる。
【００２６】
【発明の実施の形態】
以下、本発明を車両に搭載される油圧源として設けられるベーンポンプに適用した実施の形態を添付図面に基づいて説明する。
【００２７】
まず、図１に本発明が適用可能なベーンポンプの一例を示す。ベーンポンプ１は、図示しないケーシングに回転可能に支持されるロータ３０と、このロータ３０に放射状に形成されるスリット３１と、このスリット３１から摺動可能に突出する１０枚のベーン２と、各ベーン２の外周端部を摺接させてベーン室５を画成するカム２０と、ロータ３０及び各ベーン２の側端部を摺接させてベーン室５を画成するサイドプレート５０とを主体として構成される。
【００２８】
ロータ３０は起動源からの回転が図示しない駆動軸を介して伝達され、図１に矢印で示すように回転する。各ベーン２は回転するロータ３０に対しそのラジアル方向に出入りしながらそれぞれの外周端部をカム２０の内周面に摺接させてベーン室５を拡縮する。
【００２９】
サイドプレート５０には対の吸込ポート３と対の吐出ポート４が形成される。ロータ３０の回転に伴って各ベーン２間で拡がるベーン室５には吸込ポート３から作動油が吸込まれ、各ベーン２間で収縮するベーン室５から作動油が吐出ポート４に吐出される。本実施の形態では、吸込ポート３は図示しない吸込通路を介してタンクに連通し、吐出ポート４はポンプ吐出通路を介して図示しない油圧アクチュエータに連通している。
【００３０】
サイドプレート５０には周方向に延びる背圧溝５１が形成される。この背圧溝５１には吐出ポート４の圧力が導かれ、この圧力により各ベーン２がロータ３０からラジアル方向に押し出される。
【００３１】
カム２０は、吸込ポート３と吐出ポート４が開口する領域に各ベーン２を摺接させてラジアル方向に変位させるカム曲線部２３を有し、吸込ポート３と吐出ポート４の間に位置する圧力遷移行程で各ベーン２を摺接させてラジアル方向の変位を小さくしたカム大円弧部２１とを有する。カム大円弧部２１はロータ３０の回転軸を中心とする所定の半径で湾曲する円弧面状に形成され、各ベーン２をロータ３０から所定の最大量で突出した状態を維持しながら摺接させるようになっている。
【００３２】
サイドプレート５０には吐出ポート４の一端から周方向に延びるノッチ５２が形成される。ノッチ５２は断面三角形の溝状に窪み、その深さが先端５２ａにかけて次第に小さくなっている。このノッチ５２は吸込行程から吐出行程に至る圧力遷移行程で、ベーン室５を吐出ポート４に連通する。
【００３３】
そして本発明は、図２の（ａ），（ｂ），（ｃ）図に示すように、圧力遷移行程でベーン室５と吐出ポート４を結ぶ圧力導入路１０を備える。
【００３４】
図２の（ｂ），（ｃ）はカム２０及びロータ３０等を展開した図であり、ロータ３０は図中白抜き矢印で示す方向に回転し、ベーン室５は同方向に移動する。本実施の形態では、圧力導入路１０としてサイドプレート５０のベーン２に摺接する表面に開口する導入孔５５が形成される。
【００３５】
導入孔５５はノッチ５２より吸込ポート３側に位置して開口する。そして、導入孔５５はベーン室５が吸込ポート３との連通を遮断すると略同時にベーン室５に重合して接続する位置に形成され、圧力遷移行程の初期から吐出ポート４の作動油が導入孔５５を通ってベーン室５に流入する構成とする。
【００３６】
図２の（ｃ）に示すように、導入孔５５はその先端にオリフィス５６を有し、このオリフィス５６の開口径を任意に設定することにより、圧力遷移行程でベーン室５の圧力上昇速度が略一定になるようにする。
【００３７】
導入孔５５はその延長線がノッチ５２の延長線と交差するように開口し、導入孔５５を通ってベーン室５に流入する作動油をノッチ５２を通ってベーン室５に流入する作動油に衝突させる構成とする。導入孔５５はサイドプレート５０の表面に対して直交して開口する一方、ノッチ５２の底部はサイドプレート５０の表面に対して傾斜している。
【００３８】
以上のように構成されて、次に作用について説明する。
【００３９】
ロータ３０の回転に伴って各ベーン２の間に画成されるベーン室５は吸込ポート３に面する領域で拡大して吸込ポート３から作動油を吸込み、吐出ポート４に面する領域で収縮して作動油を吐出ポート４に吐出する。
【００４０】
ベーン室５が吸込ポート３との連通を遮断すると同時に導入路１０が吐出ポート４と連通し、続いてノッチ５２が吐出ポート４と連通し、圧力遷移行程でベーン室５の圧力が吐出ポート４と同等に高められる。これにより、吐出ポート４の圧力が導入孔５５及びノッチ５２を介してベーン室５に導かれる行程を最大限に確保し、気泡含有率が増加した状態でも図３に示すように圧力遷移行程で圧力上昇が十分に行われ、気泡含有率の変動に起因したベーンポンプ１の振動や騒音を抑えられるとともに、ベーンポンプ１の圧力脈動を抑えられる。
【００４１】
ロータ３０の回転速度が高まり、ベーン室５の圧力が高まると、圧力導入路１０からの供給油量は圧力導入路１０の前後差圧の低下に伴って減少するため、圧力遷移行程の終了直前でベーン室５の圧力が急激に上昇することを回避し、ベーンポンプ１の振動や騒音を有効に抑えられる。
【００４２】
圧力導入路１０がノッチ５２の吸込ポート３側に位置して開口することにより、ノッチ５２の開口面積が減少しているため、上記ロータ３０の高回転時に圧力上昇を抑える効果を高められる。
【００４３】
導入孔５５はオリフィス５６の開口径を任意に設定し、圧力遷移行程でベーン室５の圧力上昇速度を略一定にすることにより、ベーンポンプ１の騒音を有効に低減できる。また、導入孔５５にオリフィス５６を形成することにより、作動油が吐出ポート４からベーン室５へ急激に逆流することが抑えられ、ベーンポンプ１の圧力脈動を低減できる。
【００４４】
図２の（ｃ）に矢印で示すように、導入孔５５を通ってベーン室５に流入する作動油がノッチ５２を通ってベーン室５に流入する作動油に衝突することにより、導入孔５５から噴出する作動油の流れを拡散する。これにより、導入孔５５からの噴流に発生するキャビテーション気泡がサイドプレート５０の一箇所に衝突することが回避され、サイドプレート５０の表面に壊食が生じることを防止できる。
【００４５】
次に図４の（ａ），（ｂ）に示す他の実施の形態を説明する。なお、前記実施の形態と同一構成部には同一符号を付す。
【００４６】
ロータ３０に複数の凹部３２が各ベーン２間に形成される一方、導入孔５５がロータ３０の側面３３または凹部３２に対峙する位置に開口し、各凹部３２によって導入孔５５が所定のタイミングで開かれる構成とする。
【００４７】
導入孔５５は圧力遷移行程の前半に凹部３２に開口して開かれ、圧力遷移行程の後半に凹部３２が外れて側面３３によって閉じられる。
【００４８】
図４の（ａ）に矢印で示すように、導入孔５５はその延長線がノッチ５２の延長線と交差するように開口し、導入孔５５を通ってベーン室５に流入する作動油をノッチ５２を通ってベーン室５に流入する作動油に衝突させ、拡散する構成とする。
【００４９】
この場合、導入孔５５は圧力遷移行程の前半に開かれ、ベーン室５の昇圧が進んだ圧力遷移行程の後半に閉じることにより、ロータ３０の高回転時に圧力遷移行程でベーン室５の圧力が急激に上昇することを回避し、ベーンポンプ１の振動や騒音を有効に抑えられる。
【００５０】
次に図５の（ａ），（ｂ）に示す他の実施の形態を説明する。なお、前記実施の形態と同一構成部には同一符号を付す。
【００５１】
圧力導入路としてサイドプレート５０に背圧溝５１からラジアル方向に延びる導入溝５７が形成される一方、ロータ３０に複数の凹部３２が各ベーン２間に形成され、各凹部３２によって導入溝５７を所定のタイミングで開く構成とする。
【００５２】
導入溝５７は圧力遷移行程の前半に凹部３２に重合して開かれ、圧力遷移行程の後半に凹部３２が外れて側面３３によって閉じられる。
【００５３】
図５の（ａ）に矢印で示すように、導入溝５７はその延長線がノッチ５２の延長線と交差するように開口し、導入溝５７を通ってベーン室５に流入する作動油をノッチ５２を通ってベーン室５に流入する作動油に衝突させ、拡散する構成とする。
【００５４】
この場合も、導入溝５７は圧力遷移行程の前半に開かれ、ベーン室５の昇圧が進んだ圧力遷移行程の後半に閉じることにより、ロータ３０の高回転時に圧力遷移行程の終了直前でベーン室５の圧力が急激に上昇することを回避し、ベーンポンプ１の振動や騒音を有効に抑えられる。
【００５５】
次に図６に示す他の実施の形態を説明する。なお、前記実施の形態と同一構成部には同一符号を付す。
【００５６】
圧力導入路としてロータ３０に各スリット３１とベーン室５を結ぶ導入孔３５が形成され、各スリット３１内で摺動するベーン２によって導入孔３５を所定のタイミングで開閉される構成とする。
【００５７】
導入孔３５は圧力遷移行程の前半にスリット３１から大きく伸び出したベーン２によって開かれ、圧力遷移行程の後半にスリット３１に入り込むベーン２によって閉じられる。
【００５８】
この場合も、導入孔３５は圧力遷移行程の前半に開かれ、ベーン室５の昇圧が進んだ圧力遷移行程の後半に閉じることにより、ロータ３０の高回転時に圧力遷移行程の終了直前でベーン室５の圧力が急激に上昇することを回避し、ベーンポンプ１の振動や騒音を有効に抑えられる。
【００５９】
なお、この圧力導入路がノッチより先にベーン室に連通する構成に限らず、圧力導入路がノッチと同時もしくはノッチより後にベーン室に連通する構成としても良い。
【００６０】
本発明は上記の実施の形態に限定されずに、例えばトランスミッションの油圧源以外にも適用でき、その技術的な思想の範囲内において種々の変更がなしうることは明白である。
【図面の簡単な説明】
【図１】本発明が適用されるベーンポンプの側面図。
【図２】本発明の実施の形態を示し、（ａ）はベーンポンプの断面図、（ｂ）、（ｃ）はベーンポンプの展開図。
【図３】同じく本発明と従来例を比較した作動特性図。
【図４】他の実施の形態を示し、（ａ）はベーンポンプの断面図、（ｂ）、（ｃ）はベーンポンプの展開図。
【図５】さらに他の実施の形態を示し、（ａ）はベーンポンプの断面図、（ｂ）、（ｃ）はベーンポンプの展開図。
【図６】さらに他の実施の形態を示すベーンポンプの展開図。
【符号の説明】
１　ベーンポンプ
２　ベーン
３　吸込ポート
４　吐出ポート
５　ベーン室
１０　圧力導入路
２０　カム
２１　カム大円弧部
２３　カム曲線部
３０　ロータ
３１　スリット
３２　凹部
３５　導入孔
５０　サイドプレート
５１　背圧溝
５２　ノッチ
５５　導入孔
５６　オリフィス
５７　導入溝[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an improvement of a vane pump which is used, for example, as a hydraulic pressure source for a vehicle and has a high content of air bubbles in a working fluid and is not stable.
[0002]
[Prior art]
Conventionally, as this kind of vane pump, as disclosed in Japanese Patent Application Laid-Open No. 2001-248569, for example, in order to adjust a pressure waveform in a pressure transition process from a suction process to a discharge process, precompression by a change in volume of a vane chamber is performed. And a notch that connects the vane chamber to the discharge port to mitigate the pressure change at the discharge port.
[0003]
[Problems to be solved by the invention]
By the way, the speed at which the pressure in the vane chamber rises depends on the compressibility of the hydraulic oil, and changes in particular depending on the bubble content of the hydraulic oil.
[0004]
The rate of change of the pressure in the vane chamber is expressed by the following equation.
[0005]
(Equation 1)

Here, P _v : vane chamber pressure, K _ec : equivalent bulk modulus of hydraulic oil, V _v : vane chamber volume, Q _c : apparent flow rate due to vane chamber volume change based on cam shape, Q _p1 , Q _p2 : a flow rate flowing from the suction and discharge ports, and Q ₁ : a leak flow rate from the vane chamber.
[0006]
(Equation 2)

_{Here, K fm:} the bulk modulus of the hydraulic fluid, _{K a:} volume elasticity coefficient of the air, _{X o:} a bubbly rate.
[0007]
In other words, the lower the pressure, the lower the equivalent bulk modulus, and the higher the pressure, the sharper the equivalent bulk modulus. Therefore, when this characteristic is applied to the equation of the pressure change rate, when the bubble mixing rate is large, when the pressure is low, the flow rate into the vane chamber cannot be secured unless the flow rate into the vane chamber is large, but when the pressure increases, the supply rate increases. If the flow rate is not reduced, the boosting speed will increase sharply.
[0008]
In the conventional method using a notch for adjusting the flow rate from the port, the notch opening area gradually increases in the pressure transition step, so that the supply flow rate to the vane chamber also gradually increases. For this reason, it was difficult to reduce the vibration noise under the condition of a large bubble mixing ratio.
[0009]
In addition, when the pre-compression amount is increased by changing the cam shape, the pressure change speed becomes too large under the condition that the bubble mixing ratio is reduced, causing a trapping phenomenon, and it is difficult to cope with various bubble mixing ratios. However, there is a problem that the vane pump causes vibration and noise.
[0010]
The present invention has been made in view of the above problems, and an object of the present invention is to provide a vane pump capable of suppressing vibration and noise caused by a change in bubble content.
[0011]
[Means for Solving the Problems]
According to a first aspect of the present invention, a plurality of vanes slidably protruding from a rotating rotor, a cam that slidably contacts an outer peripheral end of each vane to define a vane chamber, and slidably contacts a side end of each vane. A suction port for allowing a working fluid to flow into the vane chamber during a suction stroke in which the vane chamber expands with the rotation of the rotor, and a vane chamber with the rotation of the rotor. And a discharge port through which the working fluid flows out of the vane chamber during the contraction of the discharge stroke.
[0012]
Further, the vane chamber is provided with a pressure introduction path connecting the vane chamber and the discharge port in a pressure transition process from a suction process to a discharge process.
[0013]
According to a second aspect of the present invention, in the first aspect, a notch is formed in the side plate to connect the vane chamber to the discharge port in a pressure transition step, and the working fluid flowing into the vane chamber through the pressure introduction passage passes through the notch. In this case, the working fluid flows into the vane chamber.
[0014]
A third invention is characterized in that, in the first or second invention, an introduction hole which opens to the side plate and guides pressure from the discharge port is formed as a pressure introduction passage, and an orifice is formed in the introduction hole. It was taken.
[0015]
According to a fourth aspect of the present invention, in the first or second aspect, an introduction hole is formed in the side plate as a pressure introduction path and guides pressure from a discharge port, and the rotor is provided with a concave portion located between each vane and opened. The introduction hole is opened at a predetermined timing by the concave portion.
[0016]
According to a fifth aspect, in the first or second aspect, an introduction groove which opens to the side plate and guides pressure from the discharge port is formed as a pressure introduction path, and a concave portion which is located between the vanes and opened is formed in the rotor. The introduction groove is opened at a predetermined timing by the concave portion.
[0017]
According to a sixth aspect of the present invention, in the first or second aspect, a slit is formed in the rotor to slidably accommodate each vane, and a back pressure groove is provided in each slit to guide pressure from the discharge port. An introduction hole is formed in the rotor to connect each slit to the vane chamber, and the introduction hole is opened at a predetermined timing by a vane sliding in each slit.
[0018]
Function and Effect of the Invention
According to the first aspect, the pressure of the discharge port is guided to the vane chamber through the pressure introduction path in the pressure transition step, and even when the bubble content is increased, the pressure is sufficiently increased in the pressure transition step, and The vibration and noise of the vane pump caused by the fluctuation of the rate can be suppressed, and the pressure pulsation of the vane pump can be suppressed.
[0019]
When the rotation speed of the rotor increases and the pressure in the vane chamber increases, the amount of oil supplied from the pressure introduction path decreases as the pressure difference across the pressure introduction path decreases. The vibration and noise of the vane pump can be effectively suppressed.
[0020]
According to the second invention, the flow of the hydraulic oil ejected from the pressure introduction path is diffused by the hydraulic oil flowing into the vane chamber through the pressure introduction path colliding with the hydraulic oil flowing into the vane chamber through the notch. I do. As a result, it is possible to prevent cavitation bubbles generated in the jet from the pressure introduction path from colliding in a concentrated manner at one location, thereby preventing erosion on the surface thereof.
[0021]
According to the third aspect, the noise of the vane pump can be effectively reduced by arbitrarily setting the opening diameter of the orifice and making the pressure rising speed of the vane chamber substantially constant during the pressure transition stroke. In addition, it is possible to suppress a rapid backflow of the hydraulic oil from the discharge port to the vane chamber through the orifice, and it is possible to reduce pressure pulsation of the vane pump.
[0022]
Further, the flow rate through the orifice is hardly affected by the oil temperature, so that stable performance can be obtained in a wide temperature range.
[0023]
According to the fourth aspect, by opening the introduction hole at a predetermined timing, it is possible to avoid a sudden rise in the pressure of the vane chamber immediately before the end of the pressure transition step at the time of high rotation of the rotor, and to prevent vibration and noise of the vane pump. Can be effectively suppressed.
[0024]
According to the fifth aspect, the introduction groove is opened at a predetermined timing, so that the pressure in the vane chamber is prevented from sharply increasing immediately before the end of the pressure transition step at the time of high rotation of the rotor, and the vibration and noise of the vane pump are reduced. Can be effectively suppressed.
[0025]
According to the sixth aspect, the introduction hole is opened at a predetermined timing via the vane, so that the pressure in the vane chamber is prevented from sharply increasing immediately before the end of the pressure transition step at the time of high rotation of the rotor. Vibration and noise can be effectively suppressed.
[0026]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment in which the present invention is applied to a vane pump provided as a hydraulic pressure source mounted on a vehicle will be described with reference to the accompanying drawings.
[0027]
First, FIG. 1 shows an example of a vane pump to which the present invention can be applied. The vane pump 1 includes a rotor 30 rotatably supported by a casing (not shown), a slit 31 radially formed in the rotor 30, ten vanes 2 slidably projecting from the slit 31, and each vane. A cam 20 that slides the outer peripheral end of the vane 2 to define the vane chamber 5, and a side plate 50 that slides the side end of the rotor 30 and each vane 2 to define the vane chamber 5. Be composed.
[0028]
The rotation from the starting source is transmitted to the rotor 30 via a drive shaft (not shown), and the rotor 30 rotates as shown by an arrow in FIG. Each vane 2 slides its outer peripheral end against the inner peripheral surface of the cam 20 while moving in and out of the rotating rotor 30 in the radial direction to expand and contract the vane chamber 5.
[0029]
A pair of suction ports 3 and a pair of discharge ports 4 are formed in the side plate 50. Hydraulic oil is sucked from the suction port 3 into the vane chamber 5 that expands between the vanes 2 with the rotation of the rotor 30, and hydraulic oil is discharged from the vane chamber 5 that contracts between the vanes 2 to the discharge port 4. In the present embodiment, the suction port 3 communicates with the tank via a suction passage (not shown), and the discharge port 4 communicates with a hydraulic actuator (not shown) via a pump discharge passage.
[0030]
A back pressure groove 51 extending in the circumferential direction is formed in the side plate 50. The pressure of the discharge port 4 is guided to the back pressure groove 51, and each vane 2 is pushed out from the rotor 30 in the radial direction by this pressure.
[0031]
The cam 20 has a cam curve portion 23 for sliding each vane 2 in a radial direction by sliding each vane 2 in an area where the suction port 3 and the discharge port 4 are opened, and a pressure located between the suction port 3 and the discharge port 4. A cam large arc portion 21 in which the displacement in the radial direction is reduced by sliding the vanes 2 in a transition process. The cam large arc portion 21 is formed in a circular arc shape curved at a predetermined radius around the rotation axis of the rotor 30, and slides the vanes 2 while maintaining a state of protruding from the rotor 30 by a predetermined maximum amount. It has become.
[0032]
The side plate 50 is formed with a notch 52 extending from one end of the discharge port 4 in the circumferential direction. The notch 52 is recessed in a triangular groove shape, and its depth gradually decreases toward the tip 52a. The notch 52 communicates the vane chamber 5 with the discharge port 4 in a pressure transition step from a suction step to a discharge step.
[0033]
Further, as shown in FIGS. 2A, 2B, and 2C, the present invention includes a pressure introduction path 10 connecting the vane chamber 5 and the discharge port 4 in a pressure transition step.
[0034]
2B and 2C are developed views of the cam 20, the rotor 30, and the like. The rotor 30 rotates in a direction indicated by a white arrow in the figure, and the vane chamber 5 moves in the same direction. In the present embodiment, an introduction hole 55 is formed as a pressure introduction passage 10 on the surface of the side plate 50 that is in sliding contact with the vane 2.
[0035]
The introduction hole 55 is located closer to the suction port 3 than the notch 52 and opens. The introduction hole 55 is formed at a position where the vane chamber 5 cuts off communication with the suction port 3 and almost simultaneously overlaps with and connects to the vane chamber 5, and the hydraulic oil of the discharge port 4 is supplied from the beginning of the pressure transition process. It is configured to flow into the vane chamber 5 through 55.
[0036]
As shown in FIG. 2 (c), the introduction hole 55 has an orifice 56 at its tip, and by setting the opening diameter of the orifice 56 arbitrarily, the pressure rise speed of the vane chamber 5 in the pressure transition stroke is reduced. Make it almost constant.
[0037]
The introduction hole 55 is opened such that its extension line intersects with the extension line of the notch 52, and the hydraulic oil flowing into the vane chamber 5 through the introduction hole 55 is changed to the hydraulic oil flowing into the vane chamber 5 through the notch 52. It is configured to collide. The introduction hole 55 opens perpendicular to the surface of the side plate 50, while the bottom of the notch 52 is inclined with respect to the surface of the side plate 50.
[0038]
The operation as described above will now be described.
[0039]
As the rotor 30 rotates, the vane chamber 5 defined between the vanes 2 expands in a region facing the suction port 3, sucks hydraulic oil from the suction port 3, and contracts in a region facing the discharge port 4. Then, the hydraulic oil is discharged to the discharge port 4.
[0040]
At the same time as the vane chamber 5 cuts off the communication with the suction port 3, the introduction passage 10 communicates with the discharge port 4, and subsequently, the notch 52 communicates with the discharge port 4. As high as. Thereby, the stroke in which the pressure of the discharge port 4 is guided to the vane chamber 5 through the introduction hole 55 and the notch 52 is maximized, and even in the state where the bubble content is increased, the pressure transition stroke is performed as shown in FIG. The pressure is sufficiently increased, and the vibration and noise of the vane pump 1 caused by the fluctuation of the bubble content can be suppressed, and the pressure pulsation of the vane pump 1 can be suppressed.
[0041]
When the rotation speed of the rotor 30 increases and the pressure in the vane chamber 5 increases, the amount of oil supplied from the pressure introduction passage 10 decreases with a decrease in the differential pressure across the pressure introduction passage 10. As a result, the pressure in the vane chamber 5 can be prevented from rapidly increasing, and the vibration and noise of the vane pump 1 can be effectively suppressed.
[0042]
Since the pressure introducing passage 10 is located on the suction port 3 side of the notch 52 and opened, the opening area of the notch 52 is reduced, so that the effect of suppressing the pressure increase when the rotor 30 rotates at a high speed can be enhanced.
[0043]
The noise of the vane pump 1 can be effectively reduced by arbitrarily setting the opening diameter of the orifice 56 of the introduction hole 55 and making the pressure rise speed of the vane chamber 5 substantially constant during the pressure transition process. Further, by forming the orifice 56 in the introduction hole 55, the rapid backflow of the hydraulic oil from the discharge port 4 to the vane chamber 5 is suppressed, and the pressure pulsation of the vane pump 1 can be reduced.
[0044]
As shown by an arrow in FIG. 2C, the hydraulic oil flowing into the vane chamber 5 through the introduction hole 55 collides with the hydraulic oil flowing into the vane chamber 5 through the notch 52, whereby the introduction hole 55 is formed. Diffuses the flow of hydraulic oil ejected from the This prevents cavitation bubbles generated in the jet from the introduction hole 55 from colliding with one portion of the side plate 50, thereby preventing erosion on the surface of the side plate 50.
[0045]
Next, another embodiment shown in FIGS. 4A and 4B will be described. The same components as those of the above-described embodiment are denoted by the same reference numerals.
[0046]
While the plurality of recesses 32 are formed in the rotor 30 between the vanes 2, the introduction holes 55 are opened at positions facing the side surfaces 33 or the recesses 32 of the rotor 30, and the introduction holes 55 are formed by the respective recesses 32 at a predetermined timing. Open configuration.
[0047]
The introduction hole 55 is opened and opened to the concave portion 32 in the first half of the pressure transition process, and the concave portion 32 comes off and is closed by the side surface 33 in the second half of the pressure transition process.
[0048]
As shown by an arrow in FIG. 4A, the introduction hole 55 is opened such that its extension line intersects with the extension line of the notch 52, so that the working oil flowing into the vane chamber 5 through the introduction hole 55 is notched. A configuration is adopted in which the hydraulic fluid collides with the hydraulic oil flowing into the vane chamber 5 through the air passage 52 and diffuses.
[0049]
In this case, the introduction hole 55 is opened in the first half of the pressure transition process, and closed in the second half of the pressure transition process in which the pressure in the vane chamber 5 is increased, so that the pressure in the vane chamber 5 is increased during the pressure transition process when the rotor 30 is rotating at a high speed. A sudden rise is avoided, and vibration and noise of the vane pump 1 can be effectively suppressed.
[0050]
Next, another embodiment shown in FIGS. 5A and 5B will be described. The same components as those of the above-described embodiment are denoted by the same reference numerals.
[0051]
An introduction groove 57 extending in the radial direction from the back pressure groove 51 is formed in the side plate 50 as a pressure introduction passage, while a plurality of recesses 32 are formed between the vanes 2 in the rotor 30, and the introduction groove 57 is formed by each recess 32. Open at a predetermined timing.
[0052]
The introduction groove 57 is overlapped with the concave portion 32 in the first half of the pressure transition process and is opened.
[0053]
As shown by an arrow in FIG. 5A, the introduction groove 57 is opened such that its extension line intersects with the extension line of the notch 52, and the operating oil flowing into the vane chamber 5 through the introduction groove 57 is notched. A configuration is adopted in which the hydraulic fluid collides with the hydraulic oil flowing into the vane chamber 5 through the air passage 52 and diffuses.
[0054]
In this case as well, the introduction groove 57 is opened in the first half of the pressure transition stroke and closed in the second half of the pressure transition stroke in which the pressure in the vane chamber 5 has been increased, so that the rotor 30 is rotated at a high speed and immediately before the end of the pressure transition stroke. 5 can be prevented from rapidly increasing, and the vibration and noise of the vane pump 1 can be effectively suppressed.
[0055]
Next, another embodiment shown in FIG. 6 will be described. The same components as those of the above-described embodiment are denoted by the same reference numerals.
[0056]
Introducing holes 35 connecting the slits 31 and the vane chambers 5 are formed in the rotor 30 as pressure introducing paths, and the introducing holes 35 are opened and closed at predetermined timing by the vanes 2 sliding in the slits 31.
[0057]
The introduction hole 35 is opened by the vane 2 greatly extending from the slit 31 in the first half of the pressure transition stroke, and is closed by the vane 2 entering the slit 31 in the second half of the pressure transition stroke.
[0058]
Also in this case, the introduction hole 35 is opened in the first half of the pressure transition process and closed in the second half of the pressure transition process in which the pressure in the vane chamber 5 has been increased, so that the rotor 30 is rotated at high speed and immediately before the end of the pressure transition process. 5 can be prevented from rapidly increasing, and the vibration and noise of the vane pump 1 can be effectively suppressed.
[0059]
The pressure introduction path is not limited to the configuration in which the pressure introduction path communicates with the vane chamber before the notch, and the pressure introduction path may be configured to communicate with the vane chamber at the same time as the notch or after the notch.
[0060]
The present invention is not limited to the above-described embodiment, but can be applied to, for example, other than the hydraulic pressure source of the transmission, and it is apparent that various changes can be made within the technical idea.
[Brief description of the drawings]
FIG. 1 is a side view of a vane pump to which the present invention is applied.
FIG. 2 shows an embodiment of the present invention, in which (a) is a sectional view of a vane pump, and (b) and (c) are developed views of the vane pump.
FIG. 3 is an operation characteristic diagram comparing the present invention and a conventional example.
4A and 4B show another embodiment, in which FIG. 4A is a sectional view of a vane pump, and FIGS. 4B and 4C are development views of the vane pump.
5A and 5B show still another embodiment, wherein FIG. 5A is a sectional view of a vane pump, and FIGS. 5B and 5C are development views of the vane pump.
FIG. 6 is a development view of a vane pump showing still another embodiment.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 vane pump 2 vane 3 suction port 4 discharge port 5 vane chamber 10 pressure introduction path 20 cam 21 cam large arc 23 cam curve 30 rotor 31 slit 32 recess 35 introduction hole 50 side plate 51 back pressure groove 52 notch 55 introduction hole 56 Orifice 57 introduction groove

Claims (6)

A plurality of vanes slidably projecting from the rotating rotor;
A cam that slides the outer peripheral end of each vane to define a vane chamber;
A side plate that defines a vane chamber by sliding a side end of each vane,
A suction port through which a working fluid flows into the vane chamber in a suction stroke in which the vane chamber expands with the rotation of the rotor on the side plate;
A discharge port for discharging a working fluid from the vane chamber in a discharge stroke in which the vane chamber contracts with rotation of the rotor,
A vane pump, wherein the vane chamber has a pressure introduction path connecting the vane chamber and a discharge port in a pressure transition process from a suction process to a discharge process. A working fluid flowing into the vane chamber through the pressure introduction passage into the vane chamber through the pressure introduction passage is formed with a notch communicating the vane chamber with the discharge port in the pressure transition process on the side plate. The vane pump according to claim 1, wherein the vane pump is configured to collide with the vane pump. Forming an introduction hole that opens to the side plate and guides pressure from the discharge port as the pressure introduction path,
The vane pump according to claim 1, wherein an orifice is formed in the introduction hole. Forming an introduction hole that opens to the side plate and guides pressure from the discharge port as the pressure introduction path,
Forming a concave portion that is located between the vanes and that opens in the rotor,
The vane pump according to claim 1, wherein an introduction hole is opened at a predetermined timing by the concave portion. Forming an introduction groove that opens to the side plate and guides pressure from the discharge port as the pressure introduction path,
Forming a concave portion that is located between the vanes and that opens in the rotor,
The vane pump according to claim 1, wherein the introduction groove is opened at a predetermined timing by the concave portion. Forming a slit for slidably storing each of the vanes in the rotor,
Each slit has a back pressure groove for guiding pressure from the discharge port,
Forming an introduction hole connecting each slit and the vane chamber to the rotor as the pressure introduction path,
The vane pump according to claim 1 or 2, wherein the introduction hole is opened at a predetermined timing by each vane sliding on each slit.

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