JPH0541099Y2

JPH0541099Y2 -

Info

Publication number: JPH0541099Y2
Application number: JP2926990U
Authority: JP
Priority date: 1989-12-01
Filing date: 1990-03-22
Publication date: 1993-10-18
Anticipated expiration: 2003-10-18
Also published as: JPH03107260U

Description

【考案の詳細な説明】〔産業上の利用分野〕本考案は、車両のブレーキやクラツチを液圧で
作動する液圧マスタシリンダに係り、詳しくは、
シリンダボデイに装置される作動ピストン等の組
付け性を向上しつつ、シリンダボデイの軽量及び
コンパクト化を図つたセンタバルブ型の液圧マス
タシリンダに関する。[Detailed description of the invention] [Industrial application field] The present invention relates to a hydraulic master cylinder that operates vehicle brakes and clutches using hydraulic pressure.
The present invention relates to a center valve type hydraulic master cylinder that is lightweight and compact while improving the ease of assembling an operating piston, etc. installed in the cylinder body.

[Conventional technology]

作動ピストンにバルブステムを挿通配置したセ
ンタバルブ型の液圧マスタシリンダとして、例え
ば特開昭62−8854号公報に示されるものがある。
この液圧マスタシリンダは、シリンダボデイに形
成されたシリンダ孔内に、一対の液圧発生機構を
備えるタンデム型で、各液圧発生機構は、有底円
筒状のシリンダ孔に移動可能に内挿される作動ピ
ストンを持ち、各作動ピストンのシリンダ孔底部
側に液圧室が、また作動ピストンのシリンダ孔開
口部側に給油室がそれぞれ画成される。 An example of a center valve type hydraulic master cylinder in which a valve stem is inserted through an operating piston is disclosed in Japanese Patent Application Laid-Open No. 62-8854.
This hydraulic master cylinder is a tandem type having a pair of hydraulic pressure generating mechanisms in a cylinder hole formed in the cylinder body, and each hydraulic pressure generating mechanism is movably inserted into the cylinder hole in the shape of a cylinder with a bottom. A hydraulic chamber is defined on the bottom side of the cylinder hole of each working piston, and an oil supply chamber is defined on the opening side of the cylinder hole of each working piston.

作動ピストンの中心軸上には、前後の液圧室と
給油室を連通するバルブ孔と、バルブステムが挿
通されるステム孔とが形成され、バルブステムの
一端に装着されたバルブシールは、それぞれ液圧
室に突出配置される。ステム孔に連続して各作動
ピストンに形成された半径方向のガイド孔には、
作動ピストンの移動を許容し且つ作動ピストンの
ステム孔からガイド孔に突出するバルブステムの
他端を支承して、バルブステムの後退限を規制す
るガイドピンが貫挿して設けられ、非作動時に
は、バルブステムと、液圧室に縮設したリターン
スプリングの弾発力にて、シリンダ孔の開口部方
向へ付勢される作動ピストンとがガイドピンに当
接して、双方の後退限が規制されるようになつて
いる。 A valve hole that communicates the front and rear hydraulic pressure chambers with the oil supply chamber and a stem hole through which the valve stem is inserted are formed on the central axis of the operating piston, and the valve seal attached to one end of the valve stem is It is arranged to protrude into the hydraulic pressure chamber. A radial guide hole formed in each actuating piston contiguous with the stem hole includes a
A guide pin is provided to allow movement of the operating piston, support the other end of the valve stem protruding from the stem hole of the operating piston to the guide hole, and restrict the retraction limit of the valve stem. The valve stem and the actuating piston, which is urged toward the opening of the cylinder hole by the elastic force of the return spring contracted in the hydraulic chamber, come into contact with the guide pin, and the retraction limit of both is restricted. It's becoming like that.

このように構成される液圧マスタシリンダは、
液圧発生時に、作動ピストンがシリンダ孔の底部
側へ移動すると、バルブシールが作動ピストン前
端のシール面に着座してバルブ孔を閉塞し、給油
室と液圧室との連通が遮断される。バルブステム
は、バルブシールがシール面に着座した状態で、
作動ピストンと共に液圧室側へ移動し、密閉され
た液圧室を縮小しながら液圧室に液圧を発生す
る。 The hydraulic master cylinder configured in this way is
When the working piston moves toward the bottom of the cylinder hole when hydraulic pressure is generated, the valve seal seats on the sealing surface of the front end of the working piston and closes the valve hole, cutting off communication between the oil supply chamber and the hydraulic pressure chamber. With the valve seal seated on the sealing surface, the valve stem
It moves toward the hydraulic pressure chamber together with the operating piston, and generates hydraulic pressure in the hydraulic pressure chamber while contracting the sealed hydraulic chamber.

また、上述の制動作用が解除されると、作動ピ
ストンが、液圧室に縮設したリターンスプリング
の弾発力を受けて、バルブステムと共にシリンダ
孔の開口部方向へ移動して行き、次にバルブステ
ムの他端がストツパピンに当接すると、バルブシ
ールが作動ピストンのシール面から離れてバルブ
孔が開かれ、給油室内の作動液が、作動ピストン
の後退に連れて液圧室へ補給されて行き、シリン
ダ孔の開口部方向へ移動を続ける作動ピストンが
ストツパピンと当接して後退限が規制される。 Moreover, when the above-mentioned braking action is released, the actuating piston moves toward the opening of the cylinder hole together with the valve stem under the elastic force of the return spring contracted in the hydraulic chamber, and then When the other end of the valve stem comes into contact with the stopper pin, the valve seal separates from the sealing surface of the working piston, opening the valve hole, and the working fluid in the oil supply chamber is replenished into the hydraulic pressure chamber as the working piston retreats. The actuating piston, which continues to move toward the opening of the cylinder hole, comes into contact with the stopper pin, and the backward limit is regulated.

[The problem that the idea attempts to solve]

このような構成にあつては、ストツパピンを取
付ける場合に、一次側では閉塞部材や保持部材等
の部品を用いるため、部品点数が増加して製品コ
ストが嵩み、一方二次側では、シリンダ孔に作動
ピストンを差込む場合に、ガイド孔の周方向の向
きを、シリンダボデイの外部から差込まれるスト
ツパピンに合わせ煩雑に設定しなければならず、
しかもシリンダボデイには、ストツパピンを取付
けるためのねじ孔を形成する工程を必要とする。 In such a configuration, when installing the stopper pin, parts such as a closing member and a holding member are used on the primary side, which increases the number of parts and increases the product cost.On the other hand, on the secondary side, the cylinder hole When inserting the operating piston into the cylinder body, the circumferential direction of the guide hole must be set in a complicated manner to match the stopper pin inserted from the outside of the cylinder body.
Furthermore, the cylinder body requires a step of forming a screw hole for attaching the stopper pin.

また、シリンダ孔の長さとして、シリンダ孔に
内挿される構成部品に作動ピストンのストローク
が加えられるため、必然的にシリンダボデイ長さ
が長くなり、殊に上述の如き複数の作動ピストン
を持つタンデム型では、シリンダボデイの長大化
が避けられない。 Furthermore, since the stroke of the working piston is added to the component inserted into the cylinder hole, the length of the cylinder body inevitably becomes long, especially in tandem cylinders with multiple working pistons as described above. For molds, it is unavoidable that the cylinder body becomes longer.

そこで本考案は、シリンダボデイのコンパクト
化を図り、組付け性と経済性に優れたセンタバル
ブ型の車両用液圧マスタシリンダを提供すること
を目的としている。 SUMMARY OF THE INVENTION An object of the present invention is to provide a center valve type vehicle hydraulic master cylinder that has a compact cylinder body and is easy to assemble and is economical.

[Means to solve the problem]

上述の目的を達成するため、第１考案では、シ
リンダ孔に移動可能に内挿される液圧発生用の作
動ピストンに軸方向のステム孔を形成し、該ステ
ム孔にバルブステムを挿通して、バルブステムの
一端に装着されるバルブシールを、シリンダ孔に
画成される液圧室に突出配置し、前記作動ピスト
ンに半径方向のガイド孔をステム孔に連続して設
け、該ガイド孔に、作動ピストンの移動を許容し
且つ前記ステム孔からガイド孔に突出するバルブ
ステムの他端を支承して、バルブステムの後退限
を規制するストツパピンを貫挿させたセンタバル
ブ型車両用液圧マスタシリンダにおいて、前記作
動ピストンに、環状のアウタピストンをシリンダ
軸方向へ移動可能に外装して、該アウタピストン
に前記ガイド孔へ貫挿されるストツパピンを固設
し、このアウタピストンと作動ピストンとの間に
戻しスプリングを縮設して、アウタピストンをシ
リンダ孔の開口部方向へ付勢し、該シリンダ孔の
開口部側に、アウタピストンの後退限を規制する
抜止め部材を係着すると共に、シリンダ孔の底部
側に配設された作動ピストン弾発用のリターンス
プリングにてシリンダ孔の開口部方向へ付勢され
る作動ピストンを、アウタピストンに係合させて
作動ピストンの後退限を規制し、更に作動ピスト
ンが、液圧発生時にこの後退限位置からシリンダ
孔の底部側へ移動した際に、作動ピストンがアウ
タピストンと当接するまでの長さを、作動ピスト
ンのストロークよりも小さく設定している。 In order to achieve the above object, in the first invention, an axial stem hole is formed in an operating piston for generating hydraulic pressure that is movably inserted into a cylinder hole, and a valve stem is inserted into the stem hole. A valve seal attached to one end of the valve stem is disposed to protrude into a hydraulic pressure chamber defined in a cylinder hole, a radial guide hole is provided in the actuating piston continuous with the stem hole, and the guide hole includes: A center valve type vehicle hydraulic master cylinder that allows movement of an operating piston, supports the other end of the valve stem protruding from the stem hole to the guide hole, and has a stopper pin inserted therethrough for regulating the backward limit of the valve stem. An annular outer piston is mounted on the operating piston so as to be movable in the cylinder axial direction, a stopper pin that is inserted into the guide hole is fixed to the outer piston, and a stopper pin is fixed to the outer piston to be inserted into the guide hole, and between the outer piston and the operating piston, A return spring is compressed to urge the outer piston toward the opening of the cylinder hole, and a retaining member that restricts the backward limit of the outer piston is engaged with the opening side of the cylinder hole. The actuating piston, which is biased toward the opening of the cylinder hole by a return spring disposed on the bottom side of the actuating piston, engages with the outer piston to restrict the backward limit of the actuating piston, and further The length until the working piston comes into contact with the outer piston when the working piston moves from this retraction limit position to the bottom side of the cylinder hole when hydraulic pressure is generated is set smaller than the stroke of the working piston.

また第２考案では、シリンダ孔に移動可能に内
挿される液圧発生用の作動ピストンに軸方向のス
テム孔を形成し、該ステム孔にバルブステムを挿
通して、バルブステムの一端に装着されるバルブ
シールを、シリンダ孔に画成される液圧室に突出
配置し、前記作動ピストンの中間部に形成される
小径軸部に、半径方向のガイド孔をステム孔に連
続して設け、該ガイド孔に、作動ピストンの移動
を許容し且つ前記ステム孔からガイド孔に突出す
るバルブステムの他端を支承して、バルブステム
の後退限を規制するストツパピンを貫挿したセン
タバルブ型車両用液圧マスタシリンダにおいて、
前記作動ピストンを前部側分割体と後部側分割体
とを連結した２分割構成とし、前記小径軸部に環
状のアウタピストンをシリンダ軸方向へ移動可能
に外挿して、該アウタピストンに前記ガイド孔へ
貫挿されるストツパピンを固設し、このアウタピ
ストンと作動ピストンとの間に戻しスプリングを
縮設して、アウタピストンをシリンダ孔の開口部
方向へ付勢し、該アウタピストンの外周にＯリン
グ等の係止部材を装着し、前記シリンダ孔には、
この係止部材を収容して、前記戻しスプリングに
付勢されるアウタピストンの後退限を規制し且つ
このアウタピストンを後退限よりもシリンダ底部
側へは移動を許容する係合凹部を形成すると共
に、シリンダ孔の底部側に配設された作動ピスト
ン弾発用のリターンスプリングにてシリンダ孔の
開口部方向へ付勢される作動ピストンを、アウタ
ピストンに係合させて作動ピストンの後退限を規
制し、更に作動ピストンが、液圧発生時にこの後
退限位置からシリンダ孔の底部側へ移動した際
に、作動ピストンがアウタピストンと当接するま
での長さを、作動ピストンのストロークよりも小
さく設定している。 In the second invention, an axial stem hole is formed in the hydraulic pressure generating actuation piston that is movably inserted into the cylinder hole, and the valve stem is inserted into the stem hole and attached to one end of the valve stem. A valve seal is disposed to protrude into a hydraulic pressure chamber defined in the cylinder hole, and a radial guide hole is provided in a small diameter shaft portion formed in the middle portion of the actuating piston so as to be continuous with the stem hole. A center valve type vehicle fluid having a stopper pin inserted into the guide hole to allow movement of the actuating piston, support the other end of the valve stem protruding from the stem hole to the guide hole, and restrict the retraction limit of the valve stem. In the pressure master cylinder,
The operating piston has a two-part structure in which a front side divided body and a rear side divided body are connected, and an annular outer piston is movably inserted in the small diameter shaft portion in the cylinder axial direction, and the guide is attached to the outer piston. A stopper pin inserted into the hole is fixed, and a return spring is compressed between the outer piston and the operating piston to bias the outer piston toward the opening of the cylinder hole. A locking member such as a ring is attached to the cylinder hole.
An engagement recess is formed that accommodates the locking member and restricts the retraction limit of the outer piston biased by the return spring and allows the outer piston to move toward the cylinder bottom side beyond the retraction limit. The working piston, which is biased toward the opening of the cylinder hole by a return spring disposed on the bottom side of the cylinder hole for firing the working piston, engages with the outer piston to restrict the backward limit of the working piston. Furthermore, when the working piston moves from this retraction limit position to the bottom side of the cylinder hole when hydraulic pressure is generated, the length until the working piston comes into contact with the outer piston is set to be smaller than the stroke of the working piston. ing.

更に第３考案では、シリンダ孔に移動可能に内
挿される液圧発生用の作動ピストンに軸方向のス
テム孔を形成し、該ステム孔にバルブステムを挿
通して、バルブステムの一端に装着されるバルブ
シールを、シリンダ孔に画成される液圧室に突出
配置し、前記作動ピストンの中間部に形成される
小径軸部に、半径方向のガイド孔をステム孔に連
続して設け、該ガイド孔に、作動ピストンの移動
を許容し且つ前記ステム孔からガイド孔に突出す
るバルブステムの他端を支承して、バルブステム
の後退限を規制するストツパピンを貫挿したセン
タバルブ型車両用液圧マスタシリンダにおいて、
前記作動ピストンを前部側分割体と後部側分割体
とを連結した２分割構成とし、前記小径軸部に環
状のアウタピストンを外挿して両ピストン半体を
連結し、該アウタピストンに前記ガイド孔へ貫挿
されるストツパピンを固設すると共に、このアウ
タピストンを、Ｏリング等の係止部材にて前記シ
リンダ孔に固定し、該アウタピストンに、シリン
ダ孔の底部側に配設された作動ピストン弾発用の
リターンスプリングにてシリンダ孔の開口部方向
へ付勢される作動ピストンを支承させて、作動ピ
ストンの後退限を規制している。 Furthermore, in the third invention, an axial stem hole is formed in an actuating piston for generating hydraulic pressure that is movably inserted into a cylinder hole, a valve stem is inserted into the stem hole, and the valve stem is attached to one end of the valve stem. A valve seal is disposed to protrude into a hydraulic pressure chamber defined in the cylinder hole, and a radial guide hole is provided in a small diameter shaft portion formed in the middle portion of the actuating piston so as to be continuous with the stem hole. A center valve type vehicle fluid having a stopper pin inserted into the guide hole to allow movement of the actuating piston, support the other end of the valve stem protruding from the stem hole to the guide hole, and restrict the retraction limit of the valve stem. In the pressure master cylinder,
The operating piston has a two-part structure in which a front side divided body and a rear side divided body are connected, and an annular outer piston is inserted into the small diameter shaft portion to connect both piston halves, and the guide is attached to the outer piston. A stopper pin inserted into the hole is fixed, and this outer piston is fixed to the cylinder hole with a locking member such as an O-ring, and an actuating piston arranged on the bottom side of the cylinder hole is attached to the outer piston. The operating piston, which is urged toward the opening of the cylinder hole, is supported by an elastic return spring, and the backward limit of the operating piston is regulated.

また、第４考案では、シリンダ孔の開口部側に
一次用の液圧発生機構を、該シリンダ孔の底部側
に二次用の液圧発生機構を配設して、両液圧発生
機構の間に第１液圧室を、二次用の液圧発生機構
とシリンダ孔の底部との間に第２液圧室をそれぞ
れ画成し、各液圧発生機構に、前記シリンダ孔に
移動可能に内挿される作動ピストンと、該作動ピ
ストンに形成された軸方向のステム孔に挿通さ
れ、一端に装着されたバルブシールをそれぞれの
液圧室に突出させたバルブステムと、前記ステム
孔に連続して作動ピストンに形成された半径方向
のガイド孔に挿通されるストツパピンとを備え、
前記シリンダ孔に、それぞれの液圧発生機構とリ
ザーバとを連通する連通路を開口して設けたタン
デム式のセンタバルブ型車両用液圧マスタシリン
ダにおいて、前記一次用液圧発生機構を、作動ピ
ストンに環状のアウタピストンをシリンダ軸方向
へ移動可能に外装して、該アウタピストンに、前
記ガイド孔へ貫挿されるストツパピンと、前記作
動ピストンに設けられた前部側カツプシールと共
にシリンダ孔を液密に摺動する後部側カツプシー
ルとを装着し、このアウタピストンと作動ピスト
ンとの間に戻しスプリングを縮設して、アウタピ
ストンをシリンダ孔の開口部方向へ付勢し、該シ
リンダ孔の開口部側に、アウタピストンの後退限
を規制する抜止め部材を係着すると共に、シリン
ダ孔の底部側に配設されたリターンスプリングに
てシリンダ孔の開口部方向へ付勢される作動ピス
トンを、アウタピストンに係合させて作動ピスト
ンの後退限を規制する構成とし、更に液圧発生時
に、前記アウタピストンの後部側カツプシール
が、この後退限位置から前記連通路へ到達するま
でのストロークをＥに、同じくこの作動ピストン
が、二次用液圧発生機構の作動ピストンに当接す
るまでのストロークをＡに、また二次用液圧発生
機構の作動ピストンが、前記シリンダ孔の底部に
当接するまでのストロークをＢに、更に一次用液
圧発生機構の作動ピストンが、前記アウタピスト
ンと当接するまでのクリアランスをＣとした場合
に、Ｅ＝Ａ＋Ｂ−Ｃの関係となるように、前記一
次用液圧発生機構の後部側カツプシールの位置を
設定している。 In addition, in the fourth invention, a primary hydraulic pressure generating mechanism is disposed on the opening side of the cylinder hole, and a secondary hydraulic pressure generating mechanism is disposed on the bottom side of the cylinder hole. A first hydraulic pressure chamber is defined in between, and a second hydraulic chamber is defined between the secondary hydraulic pressure generating mechanism and the bottom of the cylinder hole, and each hydraulic pressure generating mechanism is movable to the cylinder hole. an actuating piston inserted into the actuating piston; a valve stem that is inserted into an axial stem hole formed in the actuating piston and has a valve seal attached to one end protruding into each hydraulic pressure chamber; and a stopper pin inserted into a radial guide hole formed in the actuating piston,
In a tandem type center valve type vehicle hydraulic master cylinder in which a communication passage is opened in the cylinder hole to communicate between each hydraulic pressure generating mechanism and a reservoir, the primary hydraulic pressure generating mechanism is connected to the actuating piston. An annular outer piston is mounted so as to be movable in the axial direction of the cylinder, and the outer piston, together with a stopper pin inserted into the guide hole and a front cup seal provided on the operating piston, makes the cylinder hole liquid-tight. A sliding rear cup seal is installed, and a return spring is compressed between the outer piston and the operating piston to urge the outer piston toward the opening of the cylinder hole. A retaining member that restricts the retraction limit of the outer piston is engaged with the outer piston, and the actuating piston, which is urged toward the opening of the cylinder hole by a return spring disposed on the bottom side of the cylinder hole, is attached to the outer piston. The rear cup seal of the outer piston has a stroke E from the rear end position of the outer piston until it reaches the communication passage when hydraulic pressure is generated. A is the stroke until this working piston comes into contact with the working piston of the secondary hydraulic pressure generation mechanism, and A is the stroke until the working piston of the secondary hydraulic pressure generating mechanism comes into contact with the bottom of the cylinder hole. In addition to B, when the clearance between the working piston of the primary hydraulic pressure generating mechanism and the outer piston is C, the primary hydraulic pressure generating mechanism is adjusted so that the relationship E=A+B−C is satisfied. The position of the rear cup seal is set.

[Effect]

これら各考案では、シリンダ孔に内挿される構
成部品が予めユニツトとして組付けられ、シリン
ダ孔へユニツト状態で挿込まれる。アウタピスト
ンには、ストツパピンが一体に組付けされている
ため、シリンダ孔への差込みに周方向の限定がな
い。 In each of these designs, the components to be inserted into the cylinder hole are assembled in advance as a unit, and are inserted into the cylinder hole as a unit. Since the stopper pin is integrally assembled with the outer piston, there is no restriction in the circumferential direction when it can be inserted into the cylinder hole.

係止部材は、第２及び第３考案で、シリンダ孔
へ圧縮しながら差込まれ、係合凹部で拡開して係
合する。各考案において制動作用が行なわれる
と、作動ピストンがシリンダ孔の底部側へ移動し
て、液圧室に液圧を発生する。アウタピストンを
固定しない第１及び第２考案では、先ず作動ピス
トンが移動し、次に作動ピストンがアウタピスト
ンと係合して、両ピストンがシリンダ孔の底部側
へ一体に移動する。またタンデム式の第４考案で
は、一次及び二次用液圧発生機構の作動ピストン
とアウタピストンとが、それぞれ同様の作用を行
なう。 In the second and third inventions, the locking member is inserted into the cylinder hole while being compressed, and is expanded and engaged in the engagement recess. When a braking action is performed in each device, the actuating piston moves toward the bottom of the cylinder hole and generates hydraulic pressure in the hydraulic pressure chamber. In the first and second designs in which the outer piston is not fixed, first the working piston moves, then the working piston engages with the outer piston, and both pistons move together toward the bottom side of the cylinder hole. Furthermore, in the fourth design of the tandem type, the actuating piston and the outer piston of the primary and secondary hydraulic pressure generating mechanisms each perform the same function.

更に、第１考案では、作動ピストンの移動開始
から、作動ピストンがアウタピストンと当接する
までの長さがシリンダ孔の短縮長さとなり、また
第４考案では、クリアランスＣ分の長さがシリン
ダボデイの短縮長さとなる。 Furthermore, in the first design, the length from the start of movement of the working piston until the working piston comes into contact with the outer piston is the shortened length of the cylinder hole, and in the fourth design, the length corresponding to the clearance C is the shortened length of the cylinder body. The shortened length is .

〔Example〕

以下、本考案の一実施例を図面に基づいて説明
する。 Hereinafter, one embodiment of the present invention will be described based on the drawings.

液圧マスタシリンダ１は、シリンダボデイ２に
穿設された有底円筒状のシリンダ孔３内に、一次
用の液圧発生機構４と二次用の液圧発生機構５と
を備えるタンデム型で、負圧倍力装置６の前部に
連結されるシリンダボデイ２は、上部に補助油槽
７が一体に設けられ、該補助油槽７に、作動液を
貯留する合成樹脂製のリザーバ８がクランプ９を
用いて嵌着されている。 The hydraulic master cylinder 1 is of a tandem type, and includes a primary hydraulic pressure generating mechanism 4 and a secondary hydraulic pressure generating mechanism 5 in a bottomed cylindrical cylinder hole 3 bored in a cylinder body 2. The cylinder body 2 connected to the front part of the negative pressure booster 6 is integrally provided with an auxiliary oil tank 7 at the top, and a synthetic resin reservoir 8 for storing hydraulic fluid is connected to the clamp 9 in the auxiliary oil tank 7. It is fitted using.

一次用の液圧発生機構４は、シリンダ孔３内に
液密且つ移動可能に内挿される第１作動ピストン
４０と、二の作動ピン４０のステム孔４０ｄに挿
通される第１バルブステム４１と、同じく作動ピ
ストン４０に外挿される環状の第１アウタピスト
ン４２とを持つており、また二次用の液圧発生機
構５も同様に、第２作動ピストン５０と、ステム
孔５０ｅに挿通される第２バルブステム５１と、
環状の第２アウタピストン５２とを持つている。 The primary hydraulic pressure generating mechanism 4 includes a first actuating piston 40 that is fluid-tightly and movably inserted into the cylinder hole 3, and a first valve stem 41 that is inserted into the stem hole 40d of the second actuating pin 40. , also has an annular first outer piston 42 that is inserted outside the working piston 40, and the secondary hydraulic pressure generating mechanism 5 is similarly inserted into the second working piston 50 and the stem hole 50e. a second valve stem 51;
It has an annular second outer piston 52.

第１、第２作動ピストン４０，５０が内挿され
るシリンダ孔３には、両作動ピストン４０，５０
の間に第１液圧室４３が、また二次側の作動ピス
トン５０とシリンダ孔３の底部との間に第２液圧
室５３がそれぞれ画成される。両液圧室４３，５
３には、作動ピストン４０，５０をシリンダ孔３
の開口部方向へ付勢する第１、第２リターンスプ
リング１０，１１が縮設され、またこれら液圧室
４３，５３に形成される出力ポート４４，５４に
は、ブレーキやクラツチに連結される２系統のホ
ースが接続される。 Both working pistons 40, 50 are inserted into the cylinder hole 3 into which the first and second working pistons 40, 50 are inserted.
A first hydraulic chamber 43 is defined between the two, and a second hydraulic chamber 53 is defined between the secondary working piston 50 and the bottom of the cylinder hole 3. Both hydraulic pressure chambers 43, 5
3, the operating pistons 40 and 50 are inserted into the cylinder hole 3.
First and second return springs 10 and 11 are compressed to urge the hydraulic pressure chambers 43 and 53 toward the opening thereof, and output ports 44 and 54 formed in these hydraulic pressure chambers 43 and 53 are connected to a brake or a clutch. Two systems of hoses are connected.

上記第１、第２作動ピストン４０，５０は、第
１液圧室４３内に配設されるバルブケース４５と
連結ボルト１２とリテーナ１３とで、それぞれ別
個に前進または後退可能に連結されており、シリ
ンダ孔３を液密に摺動する前後部のカツプシール
１４ａ，１４ｂの間に、第１給油室４６と第２給
油室５６が形成され、第１給油室４６は、第１連
通路１５ａ，１５ｂと第１区画室７ａを介して、
また第２給油室５６は、第２連通路１６と第２区
画室７ｂを介して、それぞれリザーバ８と連通し
ている。 The first and second actuating pistons 40 and 50 are connected by a valve case 45 disposed in a first hydraulic chamber 43, a connecting bolt 12, and a retainer 13 so as to be able to move forward or backward independently. , a first oil supply chamber 46 and a second oil supply chamber 56 are formed between the front and rear cup seals 14a and 14b that slide liquid-tightly in the cylinder hole 3, and the first oil supply chamber 46 is connected to the first communication passage 15a, 15b and the first compartment 7a,
Further, the second oil supply chamber 56 communicates with the reservoir 8 via the second communication passage 16 and the second compartment 7b, respectively.

一次側の第１作動ピストン４０は、前部外周に
大径のフランジ４０ａを持ち、後部に小径軸部４
０ｂを持つている。小径軸部４０ｂには、上述の
アウタピストン４２が移動可能に外挿され、また
小径軸部４０ｂの後端に開口する嵌合穴４０ｃに
は、負圧倍力装置６のプツシユロツド６ａが突出
配置される。 The first working piston 40 on the primary side has a large-diameter flange 40a on the outer periphery of the front part, and a small-diameter shaft part 4 on the rear part.
It has 0b. The above-mentioned outer piston 42 is movably inserted into the small diameter shaft portion 40b, and a push rod 6a of the negative pressure booster 6 is arranged to protrude from a fitting hole 40c that opens at the rear end of the small diameter shaft portion 40b. be done.

第１作動ピストン４０の中心軸上には、第１バ
ルブステム４１が挿通されるステム孔４０ｄと、
第１液圧室４３及び第１給油室４６とを連通する
複数のバルブ孔４０ｅとが、前端のシール面４０
ｈに開口して設けられ、また小径軸部４０ｂに
は、このステム孔４０ｄとバルブ孔４０ｅとに連
続するスリツト状のガイド孔４０ｆが、第１作動
ピストン４０の半径方向に貫通して設けられてい
る。 On the central axis of the first working piston 40, there is a stem hole 40d through which the first valve stem 41 is inserted;
A plurality of valve holes 40e that communicate with the first hydraulic chamber 43 and the first oil supply chamber 46 are connected to the sealing surface 40 at the front end.
A slit-shaped guide hole 40f, which is continuous with the stem hole 40d and the valve hole 40e, is provided in the small diameter shaft portion 40b and extends through the first actuating piston 40 in the radial direction. ing.

第１バルブステム４１は、一端に装着したバル
ブシール４１ａを、第１作動ピストン４０の先端
で第１リターンスプリング１０の一端を支承する
前述のバルブケース４５内に突出させてバルブ孔
４０ｅに挿通され、バルブシール４１ａとバルブ
ケース４５との間に縮設されるバルブスプリング
１７にて、シリンダ孔３の開口部方向へ付勢され
る。 The first valve stem 41 is inserted into the valve hole 40e with the valve seal 41a attached to one end protruding into the aforementioned valve case 45 that supports one end of the first return spring 10 at the tip of the first actuating piston 40. , is biased toward the opening of the cylinder hole 3 by a valve spring 17 compressed between the valve seal 41a and the valve case 45.

一次側の第１アウタピストン４２は、円筒部４
２ａの後端外周に、前記カツプシール１４ｂが嵌
合されるシール溝４２ｂと、第１作動ピストン４
０のフランジ４０ａと共にシリンダ孔３を摺動す
る大径のフランジ４２ｃとを持つており、円筒部
４２ａには、ピン孔４２ｄ，４２ｄが半径方向に
穿設されている。 The first outer piston 42 on the primary side has a cylindrical portion 4
A seal groove 42b into which the cup seal 14b is fitted is formed on the outer periphery of the rear end of the first actuating piston 2a.
The cylindrical portion 42a has a large-diameter flange 42c that slides in the cylinder hole 3 together with a large-diameter flange 40a, and pin holes 42d, 42d are bored in the radial direction in the cylindrical portion 42a.

このように形成される第１アウタピストン４２
は、円筒部４２ａの先端と第１作動ピストン４０
のフランジ４０ａとの間に、第１戻しスプリング
１８を縮設して、第１作動ピストン４０の小径軸
部４０ｂに外装され、ガイド孔４０ｆと位置合わ
せしたピン孔４２ｄ，４２ｄに、前記ガイド孔４
０ｆに貫挿される第１ストツパピン１９を嵌合し
て、第１作動ピストン４０の軸方向へ移動可能に
且つ周方向へ回動不能に連結される。 The first outer piston 42 formed in this way
is the tip of the cylindrical portion 42a and the first working piston 40
A first return spring 18 is compressed between the flange 40a of the first actuating piston 40, and pin holes 42d, 42d, which are mounted on the small diameter shaft portion 40b of the first actuating piston 40 and aligned with the guide hole 40f, are inserted into the guide hole. 4
A first stopper pin 19 that is inserted through 0f is fitted, and the first actuating piston 40 is connected movably in the axial direction and unrotatably in the circumferential direction.

一方、二次側の第２作動ピストン５０は、中間
部を半径方向に切断して２分割された前部側分割
体５０ａと後部側分割体５０ｂとからなつてい
る。前部側分割体５０ａは、前部外周に大径のフ
ランジ５０ｃを持ち、後部に小径軸部５０ｄを持
つている。前部側分割体５０ａの中心軸上には、
第２バルブステム５１が挿通されるステム孔５０
ｅと、第２液圧室５３及び第２給油室５６とを連
通する複数のバルブ孔５０ｆとが、前端のシール
面５０ｍに開口して設けられ、また小径軸部５０
ｄには、ステム孔５０ｅとバルブ孔５０ｆとに連
続するスリツト状のガイド孔５０ｇが、第２作動
ピストン５０の半径方向に貫通して設けられてい
る。 On the other hand, the second working piston 50 on the secondary side is composed of a front divided body 50a and a rear divided body 50b, which are divided into two parts by cutting the intermediate part in the radial direction. The front divided body 50a has a large diameter flange 50c on the outer periphery of the front part and a small diameter shaft part 50d on the rear part. On the central axis of the front side divided body 50a,
Stem hole 50 into which the second valve stem 51 is inserted
e, a plurality of valve holes 50f communicating with the second hydraulic pressure chamber 53 and the second oil supply chamber 56 are provided to open at the sealing surface 50m at the front end, and the small diameter shaft portion 50
d, a slit-shaped guide hole 50g that is continuous with the stem hole 50e and the valve hole 50f is provided so as to pass through the second actuating piston 50 in the radial direction.

第２バルブステム５１は、先端に装着したバル
ブシール５１ａを、第２作動ピストン５０の先端
で第２リターンスプリング１１の一端を支承する
バルブケース５５内に突出させてステム孔５０ｅ
に挿通され、バルブシール５１ａとバルブケース
５５との間に縮設されるバルブスプリング２０に
て、シリンダ孔３の開口部方向へ付勢される。 The second valve stem 51 has a valve seal 51a attached to the tip thereof projected into a valve case 55 that supports one end of the second return spring 11 at the tip of the second actuating piston 50, and a stem hole 50e.
The valve spring 20 is inserted into the cylinder hole 3 and compressed between the valve seal 51a and the valve case 55, and is urged toward the opening of the cylinder hole 3.

また、後部側分割体５０ｂは、外周に前記カツ
プシール１４ｂが嵌合されるシール溝５０ｈと、
前部側分割体５０ａのフランジ５０ｃと共にシリ
ンダ孔３を摺動するフランジ５０ｉとが周設さ
れ、更に先端面と後端面に嵌合穴５０ｊとボルト
収容穴５０ｋとが凹設されている。両分割体５０
ａ，５０ｂは、前部側分割体５０ａの小径軸部５
０ｄに、第２戻しスプリング２１と第２アウタピ
ストン５２とを外装し、小径軸部５０ｄの後端を
後部側分割体５０ｂの嵌合穴５０ｊに圧入して一
体化される。 Further, the rear divided body 50b has a seal groove 50h on the outer periphery in which the cup seal 14b is fitted;
A flange 50i that slides in the cylinder hole 3 together with the flange 50c of the front divided body 50a is provided around the flange 50i, and a fitting hole 50j and a bolt receiving hole 50k are recessed in the front end surface and the rear end surface. Both divided bodies 50
a, 50b are small diameter shaft portions 5 of the front side divided body 50a.
0d, the second return spring 21 and the second outer piston 52 are externally mounted, and the rear end of the small diameter shaft portion 50d is press-fitted into the fitting hole 50j of the rear side divided body 50b to be integrated.

二次側の第２アウタピストン５２は、円筒部５
２ａの外周に大径のフランジ５２ｂを持ち、該フ
ランジ５２ｂの外周にシール溝５２ｃが凹設され
ると共に、円筒部５２ａに、ピン孔５２ｄ，５２
ｄは半径方向に穿設されており、第２アウタピス
トン５２は、シール溝５２ｃにＯリング２２を嵌
着して、上述の如く、第２作動ピストン５０の両
分割体５０ａ，５０ｂを嵌合連結する前に小径軸
部５０ｄに外装され、ガイド孔５０ｇと位置合わ
せしたピン孔５２ｄ，５２ｄに、上記ガイド孔５
０ｇへ貫挿される第２ストツパピン２３を嵌合し
て、第２作動ピストン５０の軸方向へ移動可能に
且つ周方向へ回動不能に連結される。 The second outer piston 52 on the secondary side has a cylindrical portion 5
2a has a large-diameter flange 52b on the outer periphery, and a seal groove 52c is recessed on the outer periphery of the flange 52b, and pin holes 52d, 52 are formed in the cylindrical portion 52a.
d is bored in the radial direction, and the second outer piston 52 fits the O-ring 22 into the seal groove 52c to fit the two divided bodies 50a and 50b of the second working piston 50 as described above. Before connection, the guide hole 5 is inserted into the pin holes 52d, 52d which are mounted on the small diameter shaft portion 50d and aligned with the guide hole 50g.
The second stopper pin 23 inserted through the second actuating piston 50 is fitted to connect the second actuating piston 50 so as to be movable in the axial direction and unrotatable in the circumferential direction.

シリンダ孔３には、前記補助油槽７の第１区画
室７ａの略下方位置に、上述のＯリング２２を収
容する係合凹部２４が周設されている。この係合
凹部２４は、Ｏリング２２を収容して、第２戻し
スプリング２１に付勢される第２アウタピストン
５２の後退限を規制する段部２４ａと、この段部
２４ａからシリンダ孔３の底部側へ窄まり、Ｏリ
ング２２を案内して、第２アウタピストン５２の
後退限からシリンダ孔底部側への移動を許容する
テーパ面２４ｂとからなつている。 An engagement recess 24 for accommodating the above-mentioned O-ring 22 is provided around the cylinder hole 3 at a position substantially below the first compartment 7a of the auxiliary oil tank 7. The engagement recess 24 includes a stepped portion 24a that accommodates the O-ring 22 and restricts the backward limit of the second outer piston 52 urged by the second return spring 21, and a stepped portion 24a that extends from the stepped portion 24a to the cylinder hole 3. It is comprised of a tapered surface 24b that tapers toward the bottom side, guides the O-ring 22, and allows the second outer piston 52 to move from the retraction limit to the bottom side of the cylinder hole.

第１液圧室４３内に配設される前記連結ボルト
１２は、頭部１２ａをリテーナ１３内に配置さ
れ、軸部１２ｂにバルブケース４５のおねじ４５
ａを螺合して、第１リターンスプリング１０の弾
発力で離間方向へ付勢されるリテーナ１３とバル
ブケース４５とを連結している。 The connecting bolt 12 disposed within the first hydraulic pressure chamber 43 has a head 12a disposed within the retainer 13, and a shaft portion 12b connected to a male thread 45 of the valve case 45.
a is screwed together to connect the retainer 13 and the valve case 45, which are urged apart by the elastic force of the first return spring 10.

このように構成される一次用及び二次用の液圧
発生機構４，５は、シリンダ孔３に装着される前
に、予め第１作動ピストン４０から二次側のバル
ブケース５５までが、ユニツトとして一体に組付
けられる。このユニツトは、第２リターンスプリ
ング１１を内挿したシリンダ孔３に差込まれ、シ
リンダ孔３の開口部に抜止め用のサークリツプ２
５が係着される。 The primary and secondary hydraulic pressure generating mechanisms 4 and 5 configured in this way are assembled in advance from the first working piston 40 to the secondary side valve case 55 before being installed in the cylinder hole 3. It is assembled as one piece. This unit is inserted into a cylinder hole 3 into which a second return spring 11 is inserted, and a circlip 2 is attached to the opening of the cylinder hole 3 to prevent it from coming out.
5 is attached.

シリンダ孔３に差込まれた上記ユニツトは、第
１戻しスプリング１８に弾発される第１アウタピ
ストン４２が、後退限をサークリツプ２５にて規
制される。一方２次側では、シリンダ孔３へ圧縮
しながら差込まれたＯリング２２が、係合凹部２
４で拡開し、係合凹部２４の段部２４ａと係合し
て、第２戻しスプリング２１に弾発される第２ア
ウタピストン５２の後退限が規制される。 In the unit inserted into the cylinder hole 3, the first outer piston 42, which is urged by the first return spring 18, is limited in its backward movement by the circlip 25. On the other hand, on the secondary side, the O-ring 22 inserted into the cylinder hole 3 while being compressed is inserted into the engagement recess 2.
4, and engages with the stepped portion 24a of the engagement recess 24, thereby restricting the backward limit of the second outer piston 52 that is urged by the second return spring 21.

また、第１、第２作動ピストン４０，５０は、
第１、第２液圧室４３，５３に縮設される第１、
第２リターンスプリング１０，１１の弾発力に
て、それぞれシリンダ孔３の開口部方向へ付勢さ
れ、第１作動ピストン４０は、小径軸部４０ｂの
段部４０ｇが、第１アウタピストン４２の先端と
当接して、第２作動ピストン５０は、小径軸部５
０ｄの段部５０ｌが、第２アウタピストン５２の
先端と当接して、それぞれ後退限を規制される。 Further, the first and second working pistons 40 and 50 are
A first contracted to the first and second hydraulic chambers 43 and 53,
The first working piston 40 is biased toward the opening of the cylinder hole 3 by the elastic force of the second return springs 10 and 11, so that the stepped portion 40g of the small diameter shaft portion 40b is aligned with the first outer piston 42. The second actuating piston 50 is in contact with the tip of the small diameter shaft portion 5
The stepped portion 50l of 0d comes into contact with the tip of the second outer piston 52, and the backward limit of each is restricted.

第１、第２バルブステム４１，５１は、第１及
び第２作動ピストン４０，５０が、上述の後退限
位置にあるとき、ガイド孔４０ｆ，５０ｇに突出
する他端が、それぞれ第１及び第２ストツパピン
１９，２３と当接して、シリンダ孔３の底部側へ
押し戻され、各バルブシール４１ａ，５１ａが、
第１及び第２作動ピストン４０，５０のシール面
４０ｈ，５０ｍから離れて、第１液圧室４３と第
１給油室４６との連通と、第２液圧室５３と第２
給油室５６との連通がそれぞれ許容される（第１
図）。 The first and second valve stems 41 and 51 have their other ends protruding into the guide holes 40f and 50g located at the first and second valve stems, respectively, when the first and second actuating pistons 40 and 50 are in the above-mentioned backward limit positions. The two valve seals 41a, 51a come into contact with the two stopper pins 19, 23 and are pushed back to the bottom side of the cylinder hole 3.
The communication between the first hydraulic pressure chamber 43 and the first oil supply chamber 46 and the communication between the second hydraulic pressure chamber 53 and the second
Communication with the oil supply chamber 56 is allowed (first
figure).

液圧発生機構４，５が上述のように設定される
と、一次側では、液圧室４３に第１作動ピストン
４０のストロークＡが、第１ストツパピン１９の
後部に、ガイド孔４０ｆによるクリアランスＣが
それぞれ設定され、二次側では、液圧室５３に第
２作動ピストン５０のストロークＢが、後部側分
割体５０ｂと第２アウタピストン５２との間にク
リアランスD₁がそれぞれ設定されると共に、第
２ストツパピン２３の後部に、ガイド孔５０ｇに
よるクリアランスD₂が設定される。 When the hydraulic pressure generating mechanisms 4 and 5 are set as described above, on the primary side, the stroke A of the first actuating piston 40 is applied to the hydraulic pressure chamber 43, and the clearance C due to the guide hole 40f is applied to the rear part of the first stopper pin 19. are set respectively, and on the secondary side, a stroke B of the second working piston 50 is set in the hydraulic pressure chamber 53, a clearance _D1 is set between the rear side divided body 50b and the second outer piston 52, and A clearance D ₂ is set at the rear of the second stopper pin 23 by the guide hole 50g.

また、第１アウタピストン４２に嵌着された後
部側のカツプシール１４ｂは、後退限位置から第
１連通路１５ｂに到達するまでのストロークＥ
が、上記ストロークＡ＋ストロークＢ−クリアラ
ンスＣに設定され、更に第２アウタピストン５２
に嵌着された後部側のＯリング２２では、後退限
位置から第２連通路１６に到達するまでのストロ
ークＦが、上記ストロークＢ−クリアランスD₁
（若しくはクリアランスD₂のいずれか短い長さ）
に設定される。これにより、各作動ピストン４
０，５０が、それぞれのストロークＡ，Ｂを最大
に前進した場合にも、カツプシール１４ｂとＯリ
ング２２が、第１連通路１５ｂや第２連通路１６
を塞がないようになつている。 Further, the rear cup seal 14b fitted to the first outer piston 42 has a stroke E from the backward limit position to the first communication passage 15b.
is set to the above stroke A + stroke B - clearance C, and the second outer piston 52
In the rear O-ring 22 fitted to the rear O-ring 22, the stroke F from the backward limit position to the second communicating path 16 is equal to the stroke B minus the clearance D ₁
(or clearance D ₂ , whichever is shorter)
is set to This allows each working piston 4
0 and 50 advance to the maximum in their respective strokes A and B, the cup seal 14b and the O-ring 22 are not connected to the first communication passage 15b or the second communication passage 16.
It is designed so that it does not block the area.

次に、上述のように構成された本実施例の作用
を説明する。 Next, the operation of this embodiment configured as described above will be explained.

非作動時における両液圧発生機構４，５は、作
動ピストン４０，５０とアウタピストン４２，５
２が、上述の如く第１図に示す後退限位置にあ
り、バルブシール４１ａ，５１ａは、シール面４
０ｈ，５０ｍから所定量離間していて、第１液圧
室４３は第１給油室４６と、第２液圧室５３は第
２給油室５６と、それぞれバルブ孔４０ｅ，５０
ｆを介して連通している。 Both hydraulic pressure generating mechanisms 4, 5 when not in operation include operating pistons 40, 50 and outer pistons 42, 5.
2 is at the retraction limit position shown in FIG. 1 as described above, and the valve seals 41a and 51a
0h, 50m, and the first hydraulic pressure chamber 43 is connected to the first oil supply chamber 46, the second hydraulic pressure chamber 53 is connected to the second oil supply chamber 56, and the valve holes 40e, 50, respectively.
It communicates via f.

次に、制動操作によつてプツシユロツド６ａが
作動すると、第１作動ピストン４０がシリンダ孔
３の底部側へ前進し、更に第１リターンスプリン
グ１０を介して、第２作動ピストン５０がシリン
ダ孔３の底部側へ押し込まれる。 Next, when the push rod 6a is actuated by a braking operation, the first actuating piston 40 advances toward the bottom side of the cylinder hole 3, and the second actuating piston 50 moves forward to the bottom side of the cylinder hole 3 via the first return spring 10. Pushed towards the bottom.

第１、第２アウタピストン４２，５２は、両作
動ピストン４０，５０の前進初期に、各戻しスプ
リング１８，２１の弾発力にて後退限位置にその
まま止どまり、第１、第２ストツパピン１９，２
３との当接を離れた各バルブステム４１，５１
は、バルブスプリング１７，２０に押圧されてス
テム孔４０ｄ，５０ｅに没入して行き、バルブシ
ール４１ａ，５１ａがシール面４０ｈ，５０ｍに
それぞれ着座して、バルブ孔４０ｅ，５０ｆが閉
塞され、第１液圧室４３と第１給油室４６、及び
第２液圧室５３と第２給油室５６との連通が遮断
される。 At the initial stage of forward movement of both working pistons 40, 50, the first and second outer pistons 42, 52 are stopped at their respective retreat limit positions by the elastic forces of the return springs 18, 21, and the first and second stopper pins 19, 2
Each valve stem 41, 51 that has left contact with the valve
are pressed by the valve springs 17, 20 and sink into the stem holes 40d, 50e, and the valve seals 41a, 51a seat on the sealing surfaces 40h, 50m, respectively, closing the valve holes 40e, 50f and blocking communication between the first hydraulic pressure chamber 43 and the first oil supply chamber 46, and between the second hydraulic pressure chamber 53 and the second oil supply chamber 56.

作動ピストン４０，５０は、アウタピストン４
２，５２とのクリアランスＣ，Ｄを縮小しながら
前進を続け、クリアランスＣ，Ｄが埋められる
と、アウタピストン４２，５２が作動ピストン４
０，５０と一体となつて前進を開始する。 The working pistons 40 and 50 are the outer piston 4
2 and 52, and when the clearances C and D are filled, the outer pistons 42 and 52 move toward the working piston 4.
0 and 50 and start moving forward.

そして、第２液圧室５３が縮小されて行き、第
２液圧室５３内の作動液が所定値に高まると、第
２作動ピストン５０が停止状態となつて、第１作
動ピストン４０と第１アウタピストン４２のみ
が、連結ボルト１２の頭部をリテーナ１３に押し
込みながら前進し、第１液圧室４３を縮小して、
内部の作動液を所定値に昇圧する。 Then, when the second hydraulic pressure chamber 53 is reduced and the hydraulic fluid in the second hydraulic pressure chamber 53 increases to a predetermined value, the second working piston 50 comes to a stopped state, and the first working piston 40 and Only the first outer piston 42 moves forward while pushing the head of the connecting bolt 12 into the retainer 13, and contracts the first hydraulic chamber 43.
Pressurizes the internal hydraulic fluid to a predetermined value.

この時、一次用液圧発生機構４のカツプシール
１４ｂのストロークＥが、ストロークＡ＋ストロ
ークＢ−クリアランスＣに、また二次用液圧発生
機構５のＯリング２２のストロークＦが、上記ス
トロークＢ−クリアランスD₁若しくはクリアラ
ンスD₂のいずれか短い長さにそれぞれ設定され
ているので、作動ピストン４０，５０が、それぞ
れのストロークＡ，Ｂを最大に前進した場合に
も、各連通路１５ｂ，１６を閉塞することがない
ので、作動ピストン４０，５０の前進による第１
及び第２給油室４６，５６への作動液の供給が確
保される。 At this time, the stroke E of the cup seal 14b of the primary hydraulic pressure generation mechanism 4 is equal to the stroke A + stroke B - clearance C, and the stroke F of the O ring 22 of the secondary hydraulic pressure generation mechanism 5 is equal to the stroke B - clearance Since the length is set to the shorter of either D ₁ or clearance D ₂ , even when the working pistons 40 and 50 advance their respective strokes A and B to the maximum, the communication passages 15b and 16 are not blocked. Therefore, the first movement due to the advance of the working pistons 40,
And the supply of hydraulic fluid to the second oil supply chambers 46, 56 is ensured.

次に、上述の制動作用が解除されると、プツシ
ユロツド６ａが後退して、戻しスプリング１８，
２１よりもセツト荷重の高い第１及び第２リター
ンスプリング１０，１１が、その弾発力にて、作
動ピストン４０，５０をシリンダ孔３の開口部方
向へ押し戻す。 Next, when the above-mentioned braking action is released, the push rod 6a retreats and the return spring 18,
The first and second return springs 10 and 11, which have a higher set load than the return spring 21, push the actuating pistons 40 and 50 back toward the opening of the cylinder hole 3 with their elastic force.

次に、各作動ピストン４０，５０の段部４０
ｇ，５０ｌが、それぞれ第１、第２アウタピスト
ン４２，５２の先端と当接して、第１、第２バル
ブステム４１，５１が、第１及び第２ストツパピ
ン１９，２３との当接によつて押し込まれ、バル
ブシール４１ａ，５１ａがシール面４０ｈ，５０
ｍから離れて、各液圧室４３，５３がそれぞれ給
油室４６，５６と連通し、液圧室４３，５３へ作
動液の補給が開始される。 Next, the stepped portion 40 of each working piston 40, 50
g, 50l are in contact with the tips of the first and second outer pistons 42, 52, respectively, and the first and second valve stems 41, 51 are in contact with the first and second stopper pins 19, 23. The valve seals 41a and 51a are pushed in and the seal surfaces 40h and 50
The hydraulic pressure chambers 43 and 53 are communicated with the oil supply chambers 46 and 56, respectively, and supply of hydraulic fluid to the hydraulic pressure chambers 43 and 53 is started.

作動ピストン４０，５０は、第１、第２アウタ
ピストン４２，５２と一体となつてシリンダ孔３
を後退し、第１アウタピストン４２がサークリツ
プ２５に当接し、また第２アウタピストン５２
が、係合凹部２４の段部２４ａに嵌合して、それ
ぞれの後退を停止する。 The actuating pistons 40, 50 are integrated with the first and second outer pistons 42, 52 and are connected to the cylinder hole 3.
is moved backward, the first outer piston 42 contacts the circlip 25, and the second outer piston 52
are fitted into the stepped portions 24a of the engagement recesses 24 to stop their respective retreats.

本実施例は、作動ピストン４０，５０やアウタ
ピストン４２，５２を始めとする液圧発生機構
４，５の殆どの部品が、シリンダ孔３へ装着前に
ユニツト化されるので、これら部品の組付けとシ
リンダ３への装着が頗る容易に行なえる。 In this embodiment, most of the parts of the hydraulic pressure generating mechanisms 4 and 5, including the actuating pistons 40 and 50 and the outer pistons 42 and 52, are assembled into a unit before being installed in the cylinder hole 3. It is extremely easy to attach and attach to the cylinder 3.

また、前記従来例の閉塞部材や保持部材等の部
品が不要となるので、組付け性の向上と低コスト
化とが図れる。殊に、双方のストツパピン１９，
２３が、シリンダ孔３へ装着する前に予めユニツ
トとして組付けされるので、シリンダ孔３へ装着
するユニツトに、ストツパピン１９，２３による
周方向の制約がなくなつて、自由に差込むことが
でき、またストツパピン１９，２３を取付けるた
めのねじ孔を不要とすることができる。 Further, since parts such as the closing member and the holding member of the conventional example are not required, ease of assembly and cost reduction can be achieved. In particular, both stopper pins 19,
23 is pre-assembled as a unit before being installed in the cylinder hole 3, the unit to be installed in the cylinder hole 3 is free from circumferential restrictions imposed by the stopper pins 19 and 23, and can be inserted freely. Further, screw holes for attaching the stopper pins 19, 23 can be made unnecessary.

更に、一次側のカツプシール１４ｂのストロー
クＥを、ストロークＡ＋ストロークＢ−クリアラ
ンスＣに、また二次側のＯリング２２のストロー
クＦを、ストロークＢ−クリアランスD₁または
D₂にそれぞれ設定して、各作動ピストン４０，
５０が、ストロークＡ，Ｂを最大に前進した場合
に、いずれも第１連通路１５ｂや第２連通路１６
を塞がないようにしたから、両給油室４６，５６
への作動液の供給を確保すると共に、カツプシー
ル１４ｂやＯリング２２が、これら連通路１５
ｂ，１６に食われて損傷することがなくなる。 Furthermore, the stroke E of the cup seal 14b on the primary side is equal to stroke A + stroke B - clearance C, and the stroke F of the O-ring 22 on the secondary side is equal to stroke B - clearance D ₁ or
D ₂ respectively, each working piston 40,
50 advances strokes A and B to the maximum, both the first communication passage 15b and the second communication passage 16
Since I made sure not to block the oil supply chambers 46 and 56,
The cup seal 14b and O-ring 22 ensure the supply of hydraulic fluid to these communication passages 15.
b, 16 will no longer eat and damage it.

しかも、本実施例では、一次側の液圧発生機構
４の構成によつて、従来形状ではストロークＥ＝
ストロークＡ＋ストロークＢであつたのに対し、
クリアランスＣの長さ分を短縮でき、同じく二次
側の液圧発生機構５の構成によつて、従来形状で
はストロークＦ＝ストロークＢであつたのに対
し、クリアランスD₁またはD₂の長さを短縮でき
る。従つて、本実施例では、シリンダ孔３の長さ
がクリアランスＣ＋クリアランスD₁またはD₂分
短縮化され、シリンダボデイ２を短かく且つ軽量
でコンパクトに設計でき、配置スペースの少ない
エンジンルームへの取付け自由度を向上させるこ
とができる。 Moreover, in this embodiment, due to the configuration of the primary side hydraulic pressure generating mechanism 4, the stroke E=
While it was stroke A + stroke B,
The length of the clearance C can be shortened, and due to the configuration of the hydraulic pressure generating mechanism 5 on the secondary side, the length of the clearance D ₁ or D ₂ can be reduced, whereas in the conventional shape stroke F = stroke B. can be shortened. Therefore, in this embodiment, the length of the cylinder hole 3 is shortened by clearance C + clearance D ₁ or D ₂ , and the cylinder body 2 can be designed to be short, lightweight, and compact, and can be installed in the engine room with little space. The degree of freedom in installation can be improved.

尚、上記実施例の一次側では、第１ストツパピ
ン１９の後部にガイド孔４０ｆによるクリアラン
スＣを設定したが、第１アウタピストン４２の後
方へ突出する第１作動ピストン４０の小径軸部４
０ｂに、第１アウタピストン４２と係合する突部
を形成して、第１アウタピストン４２が前進する
までのクリアランスを設定してもよい。 Note that on the primary side of the above embodiment, a clearance C is set at the rear of the first stopper pin 19 by the guide hole 40f, but the small diameter shaft portion 4 of the first actuating piston 40 protruding rearward of the first outer piston 42
0b may be formed with a protrusion that engages with the first outer piston 42 to set a clearance until the first outer piston 42 moves forward.

また、二次用液圧発生機構５では、Ｏリング２
２を、第２アウタピストン５２とシリンダ孔３の
双方に嵌合して、第２アウタピストン５２を固定
させ、第２作動ピストン５０のみを作動するよう
にして、第２アウタピストン５２を第２作動ピス
トン５０の後退限規制のみに用いてもよい。この
場合、両ピストン５０，５２の間に設定されるク
リアランスD₁またはD₂は、ストロークＢよりも
若干大き目に設定され、第１，２及び第４考案の
効果のうち、組付け性と経済性の効果を果す。 In addition, in the secondary hydraulic pressure generation mechanism 5, the O-ring 2
2 is fitted into both the second outer piston 52 and the cylinder hole 3, the second outer piston 52 is fixed, and only the second actuating piston 50 is actuated. It may be used only to limit the backward movement of the actuating piston 50. In this case, the clearance D ₁ or D ₂ set between both pistons 50 and 52 is set slightly larger than the stroke B, and among the effects of the first, second and fourth inventions, ease of assembly and economy are achieved. It has a sexual effect.

更に、タンデム式を限定した第４考案を除く第
１乃至第３考案は、単独若しくは複数を組合わせ
て自由に用いることが可能である。 Furthermore, the first to third designs, excluding the fourth design which is limited to the tandem type, can be freely used alone or in combination.

[Effect of idea]

以上説明したように、第１乃至第３考案では、
作動ピストンやアウタピストンを始めとする殆ど
の部品が、シリンダ孔へ装着前にユニツト化でき
るので、部品の組付けとシリンダ孔への装着が頗
る容易に行なえる。 As explained above, in the first to third ideas,
Since most of the parts, including the operating piston and the outer piston, can be assembled into a unit before being installed in the cylinder hole, it is extremely easy to assemble the parts and install them in the cylinder hole.

また、従来用いていた閉塞部材や保持部材等の
部品が不要となるので、組付け性の向上と低コス
ト化とが図れ、しかも、ストツパピンがシリンダ
孔へ装着する前に予めユニツトとして組付けされ
るので、シリンダ孔へ装着するユニツトに、スト
ツパピンによる周方向の制約がなくなつて自由に
差込むことができ、またストツパピンを取付ける
ためのねじ孔を不要とすることができる。 In addition, since conventionally used parts such as closing members and holding members are no longer required, ease of assembly and cost reduction can be achieved.Moreover, the stopper pin can be assembled as a unit in advance before being installed in the cylinder hole. Therefore, the unit to be installed in the cylinder hole can be freely inserted without being restricted in the circumferential direction by the stopper pin, and there is no need for a screw hole for attaching the stopper pin.

更に、第１考案では、作動ピストンが、液圧発
生時にシリンダ孔の底部側へ移動した際に、作動
ピストンがアウタピストンと当接するまでの長さ
を、作動ピストンのストロークよりも小さく設定
することにより、シリンダ孔の長さを短縮化でき
て、シリンダボデイを短かく且つ軽量でコンパク
トに設計でき、配置スペースの少ないエンジンル
ームへの取付け自由度を向上させることができ
る。 Furthermore, in the first invention, when the working piston moves toward the bottom side of the cylinder hole when hydraulic pressure is generated, the length until the working piston comes into contact with the outer piston is set to be smaller than the stroke of the working piston. As a result, the length of the cylinder hole can be shortened, the cylinder body can be designed to be short, lightweight, and compact, and the degree of freedom for installation in an engine room with little space can be improved.

また、タンデム式の第４考案では、従来のシリ
ンダボデイから、両液圧発生機構のクリアランス
をプラスした長さを短縮できるので、より一層の
軽量化とコンパクト化とが図れる。 Furthermore, in the fourth design of the tandem type, the length of the conventional cylinder body plus the clearance of both hydraulic pressure generating mechanisms can be shortened, making it possible to achieve further weight reduction and compactness.

[Brief explanation of the drawing]

図は本考案の一実施例を示し、第１図は液圧マ
スタシリンダの断面正面図、第２図は一次側の作
動ピストンやアウタピストンの分解斜視図、第３
図は二次側の作動ピストンやアウタピストンの分
解斜視図面である。１……液圧マスタシリンダ、２……シリンダボ
デイ、３……シリンダ孔、１０……第１リターン
スプリング、１１……第２リターンスプリング、
１４ａ，１４ｂ……カツプシール、１７，２０…
…バルブスプリング、１８……第１戻しスプリン
グ、１９……第１ストツパピン、２１……第２戻
しスプリング、２２……本考案の係止部材となる
Ｏリング、２３……第２ストツパピン、２４……
係合凹部、２５……本考案の抜止め部材となるサ
ークリツプ、４０……第１作動ピストン、５０…
…第２作動ピストン、４０ｄ，５０ｅ……ステム
孔、４１……第１バルブステム、５１……第２バ
ルブステム、４２……第１アウタピストン、５２
……第２アウタピストン、４３……第１液圧室、
５３……第２液圧室、Ａ……第１作動ピストン４
０のストローク、Ｂ……第２作動ピストン５０の
ストローク、Ｃ……第１作動ピストン４０が第１
アウタピストン４２と当接するまでのクリアラン
ス、D₁，D₂……第２作動ピストン５０が第２ア
ウタピストン５２と当接するまでのクリアラン
ス、Ｅ……一次側のカツプシール１４ｂのストロ
ーク、Ｆ……二次側のカツプシール１４ｂのスト
ローク。 The figures show one embodiment of the present invention, in which Fig. 1 is a cross-sectional front view of a hydraulic master cylinder, Fig. 2 is an exploded perspective view of the primary side working piston and outer piston, and Fig. 3 is an exploded perspective view of the primary side working piston and outer piston.
The figure is an exploded perspective view of the secondary side working piston and outer piston. DESCRIPTION OF SYMBOLS 1... Hydraulic pressure master cylinder, 2... Cylinder body, 3... Cylinder hole, 10... First return spring, 11... Second return spring,
14a, 14b...Kap seal, 17, 20...
... Valve spring, 18 ... First return spring, 19 ... First stopper pin, 21 ... Second return spring, 22 ... O-ring serving as the locking member of the present invention, 23 ... Second stopper pin, 24 ... …
Engagement recess, 25... Circlip serving as a retaining member of the present invention, 40... First operating piston, 50...
...Second working piston, 40d, 50e...Stem hole, 41...First valve stem, 51...Second valve stem, 42...First outer piston, 52
...Second outer piston, 43...First hydraulic chamber,
53...Second hydraulic chamber, A...First working piston 4
0 stroke, B... Stroke of the second working piston 50, C... The first working piston 40 is the first
Clearance until it contacts the outer piston 42, D ₁ , D ₂ ... Clearance until the second working piston 50 contacts the second outer piston 52, E ... Stroke of the primary side cup seal 14b, F... Two Stroke of the next side cup seal 14b.

Claims

[Claims for Utility Model Registration] 1. An axial stem hole is formed in an actuating piston for generating hydraulic pressure that is movably inserted into a cylinder hole, and a valve stem is inserted into the stem hole to form one end of the valve stem. A valve seal mounted on the cylinder hole is arranged to protrude into a hydraulic pressure chamber defined in the cylinder hole, and a radial guide hole is provided in the working piston in succession to the stem hole, and the movement of the working piston is provided in the guide hole. In the center valve type vehicle hydraulic master cylinder, which supports the other end of the valve stem protruding from the stem hole to the guide hole, and has a stopper pin inserted therethrough for regulating the retraction limit of the valve stem. an annular outer piston is mounted on the piston so as to be movable in the cylinder axial direction, and a stopper pin that is inserted into the guide hole is fixed to the outer piston;
A return spring is compressed between the outer piston and the actuating piston to urge the outer piston toward the opening of the cylinder hole, and to prevent the outer piston from moving backward. At the same time as engaging the stop member, the actuating piston, which is urged toward the opening of the cylinder hole by a return spring disposed on the bottom side of the cylinder hole for repelling the actuating piston, is engaged with the outer piston. Regulates the retraction limit of the working piston,
Furthermore, when the working piston moves from this retraction limit position to the bottom side of the cylinder hole when hydraulic pressure is generated,
A center valve type vehicle hydraulic master cylinder characterized in that the length of the working piston until it comes into contact with the outer piston is set smaller than the stroke of the working piston. 2. An axial stem hole is formed in an operating piston for generating hydraulic pressure that is movably inserted into the cylinder hole, a valve stem is inserted into the stem hole, and a valve seal is attached to one end of the valve stem. A radial guide hole is provided in a small-diameter shaft portion formed in the middle portion of the actuating piston, which protrudes into a hydraulic pressure chamber defined by a cylinder hole, and is continuous with the stem hole, A center valve type vehicle hydraulic master cylinder in which a stopper pin is inserted through which the piston is allowed to move and which supports the other end of the valve stem protruding from the stem hole to the guide hole and regulates the backward limit of the valve stem, The operating piston has a two-part structure in which a front side divided body and a rear side divided body are connected, and an annular outer piston is movably inserted in the small diameter shaft portion in the cylinder axial direction, and the guide is attached to the outer piston. A stopper pin inserted into the hole is fixed, and a return spring is compressed between the outer piston and the operating piston to bias the outer piston toward the opening of the cylinder hole. A locking member such as a ring is installed, and the locking member is accommodated in the cylinder hole to regulate the retraction limit of the outer piston urged by the return spring and to move the outer piston beyond the retraction limit. An engagement recess is formed on the bottom side of the cylinder to allow movement, and the working piston is urged toward the opening of the cylinder hole by a return spring for repelling the working piston, which is disposed on the bottom side of the cylinder hole. is engaged with the outer piston to restrict the retraction limit of the actuating piston, and furthermore, when the actuating piston moves from this retraction limit position to the bottom side of the cylinder hole when hydraulic pressure is generated, the actuating piston comes into contact with the outer piston. A center valve type hydraulic master cylinder for a vehicle, characterized in that the length until contact is set smaller than the stroke of an operating piston. 3. An axial stem hole is formed in the hydraulic pressure generating actuation piston that is movably inserted into the cylinder hole, a valve stem is inserted into the stem hole, and a valve seal is attached to one end of the valve stem. A radial guide hole is provided in a small-diameter shaft portion formed in the middle portion of the actuating piston that protrudes into a hydraulic pressure chamber defined by a cylinder hole, and is continuous with the stem hole; A center valve type vehicle hydraulic master cylinder in which a stopper pin is inserted through which the piston is allowed to move and which supports the other end of the valve stem protruding from the stem hole to the guide hole and regulates the backward limit of the valve stem, The operating piston has a two-part structure in which a front side divided body and a rear side divided body are connected, and an annular outer piston is inserted into the small diameter shaft portion to connect both piston halves, and the guide is attached to the outer piston. A stopper pin inserted into the hole is fixed, and this outer piston is fixed to the cylinder hole with a locking member such as an O-ring, and an actuating piston arranged on the bottom side of the cylinder hole is attached to the outer piston. A center valve type hydraulic master cylinder for a vehicle, characterized in that a return spring for elasticity supports an operating piston that is urged toward the opening of a cylinder hole, thereby regulating the backward limit of the operating piston. 4 A primary hydraulic pressure generation mechanism is provided on the opening side of the cylinder hole, a secondary hydraulic pressure generation mechanism is provided on the bottom side of the cylinder hole, and a primary hydraulic pressure generation mechanism is provided between both hydraulic pressure generation mechanisms.
a second hydraulic pressure chamber is defined between the secondary hydraulic pressure generation mechanism and the bottom of the cylinder hole;
Each hydraulic pressure generating mechanism includes an actuation piston movably inserted into the cylinder hole, and a valve seal inserted into an axial stem hole formed in the actuation piston and attached to one end of each hydraulic pressure chamber. a valve stem that protrudes from the cylinder hole; and a stopper pin that is inserted into a radial guide hole formed in the actuating piston so as to be continuous with the stem hole, and a hydraulic pressure generating mechanism and a reservoir are respectively installed in the cylinder hole. In a tandem type center valve type vehicle hydraulic master cylinder provided with an open communication passage, the primary hydraulic pressure generating mechanism is provided with an annular outer piston mounted on the operating piston so as to be movable in the cylinder axial direction. A stopper pin that is inserted into the guide hole and a rear cup seal that slides liquid-tightly in the cylinder hole together with the front cup seal provided on the operating piston are attached to the outer piston, and the outer piston and A return spring is compressed between the actuating piston and the outer piston to urge the outer piston toward the opening of the cylinder hole, and a retaining member that restricts the retraction limit of the outer piston is engaged on the opening side of the cylinder hole. At the same time, the working piston, which is urged toward the opening of the cylinder hole by a return spring disposed at the bottom side of the cylinder hole, engages with the outer piston to restrict the backward limit of the working piston. Furthermore, when hydraulic pressure is generated, the stroke of the rear cup seal of the outer piston from this retraction limit position to the communication passage is E, and this working piston is also the working piston of the secondary hydraulic pressure generating mechanism. A is the stroke until it touches the bottom of the cylinder hole, and B is the stroke until the working piston of the secondary hydraulic pressure generation mechanism comes into contact with the bottom of the cylinder hole.
Further, when the clearance between the working piston of the primary hydraulic pressure generating mechanism and the outer piston is C, the rear side of the primary hydraulic pressure generating mechanism is set so that the relationship E=A+B−C is satisfied. A center valve type vehicle hydraulic master cylinder characterized by a set cup seal position.