JP2008296788A - Pneumatic booster and check valve with throttling for pneumatic booster - Google Patents

Pneumatic booster and check valve with throttling for pneumatic booster Download PDF

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JP2008296788A
JP2008296788A JP2007146204A JP2007146204A JP2008296788A JP 2008296788 A JP2008296788 A JP 2008296788A JP 2007146204 A JP2007146204 A JP 2007146204A JP 2007146204 A JP2007146204 A JP 2007146204A JP 2008296788 A JP2008296788 A JP 2008296788A
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valve
check valve
pressure chamber
valve body
pneumatic booster
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Mitsuhiro Endo
光弘 遠藤
Shuzo Watanabe
修三 渡辺
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Hitachi Ltd
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Hitachi Ltd
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Abstract

<P>PROBLEM TO BE SOLVED: To provide a pneumatic booster capable of enhancing brake feeling and stabilizing action of a check valve, and a check valve with throttling used for the pneumatic booster. <P>SOLUTION: The first check valve 30 with valve-opening pressure P1 and the second check valve 37 with valve-opening pressure P2 are arranged on a passage for connecting a constant pressure chamber 5 and a negative pressure source in series, and an orifice 43 is provided on a valve element 39 of the second check valve 37. Accordingly, even when stepping-in of a brake pedal is stopped on the midway, the brake feeling can be enhanced by gradually reducing a pressure of the constant pressure chamber 5 through the orifice 43 by pressure difference generated by the valve-opening pressure P2 of the second check valve 37 and gradually raising output. Here, since an outer peripheral surface of the valve element 39 is guided in an axial direction by a guide part 54 of the valve element 45, the valve element 39 is prevented from being inclined relative to an axis and action of the second check valve 37 can be stabilized. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

本発明は、自動車のディスクブレーキ等に用いられる気圧式倍力装置および該気圧式倍力装置に用いられる絞り付逆止弁に関する。   The present invention relates to a pneumatic booster used for an automobile disc brake or the like, and a check valve with a throttle used for the pneumatic booster.

一般に、ディスクブレーキを採用した自動車のブレーキシステムにおいては、ブレーキペダルとマスタシリンダとの間に気圧式倍力装置が配置される。この気圧式倍力装置は、密閉された倍力装置本体の内部が、出力軸が接続されたパワーピストンユニットによって定圧室と変圧室とに画成される。定圧室には、逆止弁を介してエンジンのインテークマニホールド（負圧源）が接続されて、変圧室には、必要に応じて大気が導入される。このような気圧式倍力装置では、定圧室を大気圧に対して負圧の状態にして、この状態で変圧室と大気とを連通させて変圧室に大気を導入する。これより、定圧室と変圧室との間に圧力差が生じて、パワーピストンユニットが定圧室側へ移動する。このようにして、入力軸に入力された力、すなわち、運転者がブレーキペダルを踏む力（以下、踏力という）は、倍力されて出力軸から出力される。   In general, in an automobile brake system employing a disc brake, a pneumatic booster is disposed between a brake pedal and a master cylinder. In this pneumatic booster, the inside of a sealed booster body is defined as a constant pressure chamber and a variable pressure chamber by a power piston unit to which an output shaft is connected. An intake manifold (negative pressure source) of the engine is connected to the constant pressure chamber via a check valve, and air is introduced into the variable pressure chamber as necessary. In such a pressure type booster, the constant pressure chamber is brought into a negative pressure state relative to the atmospheric pressure, and in this state, the variable pressure chamber and the atmosphere are communicated to introduce the atmosphere into the variable pressure chamber. Thus, a pressure difference is generated between the constant pressure chamber and the variable pressure chamber, and the power piston unit moves to the constant pressure chamber side. In this way, the force input to the input shaft, that is, the force by which the driver steps on the brake pedal (hereinafter referred to as pedaling force) is boosted and output from the output shaft.

ところで、上述した気圧式倍力装置においては、ブレーキの制動力を一定に保持する操作をした時のブレーキフィーリングを向上させることを目的として、定圧室と負圧源（インテークマニホールド）とが接続されるパイプに、定圧室側から負圧源側への気体の流動のみを許容する２つの逆止弁を直列に配置したものが知られている。例えば、特許文献１に記載の気圧式倍力装置では、第２逆止弁が第１逆止弁に対して定圧室側に配置されており、第２逆止弁には当該第２逆止弁の入口側と出口側とを常時連通させるオリフィス（絞り通路）が設けられる。この気圧式倍力装置によれば、ブレーキペダルが踏み込まれると、定圧室と変圧室との間に圧力差が生じて、パワーピストンユニットが前進する。これにより、定圧室の圧力は一旦上昇することになるが、各逆止弁が開弁されることにより当該定圧室の圧力が元の負圧に回復される。ここで、ブレーキペダルの踏み込みを停止した場合、定圧室の圧力が回復しても、各逆止弁の入口側と出口側とには、各逆止弁の開弁圧力によって生じる圧力差があるため、オリフィスを介して定圧室の圧力が徐々に抜けて、パワーピストンユニットがさらに前進して出力が増大されるようになっている。   By the way, in the above-described pneumatic booster, a constant pressure chamber and a negative pressure source (intake manifold) are connected for the purpose of improving the brake feeling when an operation is performed to keep the braking force of the brake constant. There is known a pipe in which two check valves that allow only gas flow from the constant pressure chamber side to the negative pressure source side are arranged in series in the pipe. For example, in the pneumatic booster described in Patent Document 1, the second check valve is disposed on the constant pressure chamber side with respect to the first check valve, and the second check valve includes the second check valve. An orifice (throttle passage) is provided to always communicate the inlet side and the outlet side of the valve. According to this pneumatic booster, when the brake pedal is depressed, a pressure difference is generated between the constant pressure chamber and the variable pressure chamber, and the power piston unit moves forward. As a result, the pressure in the constant pressure chamber once rises, but when each check valve is opened, the pressure in the constant pressure chamber is restored to the original negative pressure. Here, when the depression of the brake pedal is stopped, even if the pressure in the constant pressure chamber is recovered, there is a pressure difference caused by the opening pressure of each check valve between the inlet side and the outlet side of each check valve. For this reason, the pressure in the constant pressure chamber is gradually released through the orifice, and the power piston unit further advances to increase the output.

しかしながら、上述した従来の気圧式倍力装置においては、オリフィスが形成された第２逆止弁の弁体は開閉方向（軸方向）へ案内されておらず、開閉弁時に弁体に傾きが生じて当該弁体の動作が不安定になり、ブレーキフィーリングが悪化する虞がある。
第２６６２６７５号特許公報 However, in the conventional pneumatic booster described above, the valve body of the second check valve in which the orifice is formed is not guided in the opening / closing direction (axial direction), and the valve body is inclined when the valve is opened / closed. As a result, the operation of the valve body becomes unstable, and the brake feeling may deteriorate.
Japanese Patent No. 2666675

そこで、本発明は、上記事情に鑑みてなされたもので、ブレーキフィーリングを向上させることができると共に、逆止弁の動作を安定させることが可能な気圧式倍力装置および該気圧式倍力装置に用いられる絞り付逆止弁を提供することを課題としてなされたものである。   Therefore, the present invention has been made in view of the above circumstances, and can improve the brake feeling and can stabilize the operation of the check valve and the pneumatic booster. An object of the present invention is to provide a throttle check valve used in the apparatus.

上記課題を解決するために、本発明のうち請求項１に記載の発明は、倍力装置本体内を出力軸が取付けられたパワーピストンユニットによって定圧室と変圧室とに画成し、定圧室を負圧源に接続し、定圧室と負圧源とを接続する通路に、それぞれ所定の開弁圧力が設定されて定圧室側から負圧源側への気体の流動のみを許容する第１および第２の逆止弁を直列に、かつ、第２の逆止弁が定圧室側となるように配設し、さらに、第２の逆止弁の定圧室側と負圧源側とを常時連通する絞り通路を設けると共に、変圧室に大気を導入して定圧室と変圧室とに圧力差を生じさせてパワーピストンユニットを出力軸側へ移動させ、出力軸から倍力させた力を出力させる気圧式倍力装置において、第２の逆止弁は、通路に接続される弁本体と該弁本体内を移動する弁体とからなり、弁本体の内周面に形成される弁座に対して負圧源側に、弁体を通路軸方向へ案内するガイド部を有することを特徴とすることを特徴とする。
請求項２に記載の発明は、請求項１に記載の気圧式倍力装置において、第２の逆止弁は、弁体を弁座へ向けて付勢する弁ばねを弁体内部に収容することを特徴とする。
請求項３に記載の発明は、請求項１又は２に記載の気圧式倍力装置において、第２の逆止弁は、弁本体が定圧室側と負圧源側とに分割して構成され、分割された弁本体の接合部が弁本体の負圧源側に形成されることを特徴とする。
請求項４に記載の発明は、請求項１〜３のいずれかに記載の気圧式倍力装置において、絞り通路は、第２の逆止弁の弁体の段付孔によって形成されることを特徴とする。
請求項５に記載の発明は、請求項１に記載の気圧式倍力装置において、第１の逆止弁と第２の逆止弁とが一のハウジングにより一体に構成されることを特徴とする。
上記課題を解決するために、本発明のうち請求項６に記載の発明は、気圧式倍力装置の定圧室と負圧源とを接続する通路に設けられ、定圧室側から負圧源側への気体の流動のみを許容して、定圧室側と負圧源側とを常時連通する絞り通路を備える気圧式倍力装置用絞り付逆止弁において、弁座が設けられて通路に接続される弁本体と、該弁本体に収容される弁体とによって構成され、弁本体の弁座に対して負圧源側に弁体を通路軸方向へ案内するガイド部が設けられることを特徴とする。 In order to solve the above-mentioned problems, the invention according to claim 1 of the present invention is that the booster body is defined as a constant pressure chamber and a variable pressure chamber by a power piston unit to which an output shaft is attached. Is connected to the negative pressure source, and a predetermined valve opening pressure is set in each of the passages connecting the constant pressure chamber and the negative pressure source to allow only gas flow from the constant pressure chamber side to the negative pressure source side. And the second check valve are arranged in series and the second check valve is on the constant pressure chamber side, and further, the constant pressure chamber side and the negative pressure source side of the second check valve are connected to each other. In addition to providing a throttle passage that always communicates, introduces atmospheric pressure into the variable pressure chamber, creates a pressure difference between the constant pressure chamber and the variable pressure chamber, moves the power piston unit to the output shaft side, and boosts the force from the output shaft. In the pneumatic booster to output, the second check valve includes a valve body connected to the passage and the inside of the valve body. It is characterized by having a guide portion that guides the valve body in the passage axial direction on the negative pressure source side with respect to the valve seat formed on the inner peripheral surface of the valve body. And
According to a second aspect of the present invention, in the pneumatic booster of the first aspect, the second check valve houses a valve spring that biases the valve body toward the valve seat inside the valve body. It is characterized by that.
The invention according to claim 3 is the pneumatic booster according to claim 1 or 2, wherein the second check valve is configured such that the valve body is divided into a constant pressure chamber side and a negative pressure source side. The joint part of the divided valve body is formed on the negative pressure source side of the valve body.
The invention according to claim 4 is the pneumatic booster according to any one of claims 1 to 3, wherein the throttle passage is formed by a stepped hole of the valve body of the second check valve. Features.
According to a fifth aspect of the present invention, in the pneumatic booster according to the first aspect, the first check valve and the second check valve are integrally formed by a single housing. To do.
In order to solve the above-mentioned problem, the invention according to claim 6 of the present invention is provided in a passage connecting the constant pressure chamber of the pneumatic booster and the negative pressure source, from the constant pressure chamber side to the negative pressure source side. In a check valve with a throttle for a pneumatic booster equipped with a throttle passage that allows only the flow of gas to the constant pressure chamber and always connects the constant pressure chamber side and the negative pressure source side, a valve seat is provided and connected to the passage And a valve body accommodated in the valve body, and a guide portion for guiding the valve body in the axial direction of the passage is provided on the negative pressure source side with respect to the valve seat of the valve body. And

したがって、請求項１に記載の気圧式倍力装置では、第２の逆止弁の弁本体内を移動する弁体が、通路に接続される弁本体の内周面に形成される弁座に対して負圧源側に設けられたガイド部によって通路軸方向へ案内される。
請求項２に記載の気圧式倍力装置では、第２の逆止弁の弁ばねが、弁体の内部に収容される。
請求項３に記載の気圧式倍力装置では、第２の逆止弁の分割された弁本体のそれぞれが、弁座から離れた位置で接合される。
請求項４に記載の気圧式倍力装置では、絞り通路（オリフィス）は、第２の逆止弁の弁体の段付孔によって形成される。
請求項５に記載の気圧式倍力装置では、直列または並列に配置される第１の逆止弁と第２の逆止弁とが一のハウジングにより一つの逆止弁に集約される。
請求項６に記載の気圧式倍力装置用絞り付逆止弁では、弁体が、弁座が設けられて通路に接続される弁本体の内周面の、弁座に対して負圧源側に設けられたガイド部によって通路軸方向へ案内される。 Therefore, in the pneumatic booster according to claim 1, the valve body that moves in the valve body of the second check valve is formed on the valve seat formed on the inner peripheral surface of the valve body connected to the passage. On the other hand, it is guided in the passage axial direction by a guide portion provided on the negative pressure source side.
In the pneumatic booster according to the second aspect, the valve spring of the second check valve is accommodated in the valve body.
In the pneumatic booster according to the third aspect, each of the divided valve bodies of the second check valve is joined at a position away from the valve seat.
In the pneumatic booster according to the fourth aspect, the throttle passage (orifice) is formed by a stepped hole of the valve body of the second check valve.
In the pneumatic booster according to the fifth aspect, the first check valve and the second check valve arranged in series or in parallel are integrated into one check valve by one housing.
7. A check valve with a throttle for a pneumatic booster according to claim 6, wherein the valve body is provided with a valve seat and is connected to the passage on the inner peripheral surface of the valve body with a negative pressure source with respect to the valve seat. It is guided in the direction of the passage axis by a guide portion provided on the side.

請求項１に記載の気圧式倍力装置によれば、開閉弁時に弁体が軸線に対して傾くのを防止して、第２の逆止弁の動作を安定させることができ、延いては、ブレーキフィーリングを向上させることができる。
請求項２に記載の気圧式倍力装置によれば、第２の逆止弁の全長（通路軸方向長さ）が短縮されて当該逆止弁を小型化することができる。
請求項３に記載の気圧式倍力装置によれば、例えば、第２の逆止弁の弁本体を合成樹脂によって形成し、分割されたそれぞれの弁本体を溶着によって接合して一体化させる場合、溶着時における弁座及びガイド部への熱影響を最小限に抑制することが可能になり、当該逆止弁の品質を確保することができる。
請求項４に記載の気圧式倍力装置によれば、第２の逆止弁の弁体に極めて小さい孔径の絞り通路を弁体の全長に亘って形成する場合と比較して、弁体の製造が容易であり、製造コストを削減することができる。
請求項５に記載の気圧式倍力装置によれば、定圧室と負圧源との間の配管を簡易化することができる。
請求項６に記載の気圧式倍力装置用絞り付逆止弁によれば、開閉弁時に弁体が軸線に対して傾くのを防止して、逆止弁の動作を安定させることができ、延いては、当該逆止弁を用いて構成された気圧式倍力装置を有するブレーキシステムのブレーキフィーリングを向上させることができる。 According to the pneumatic booster of the first aspect, it is possible to prevent the valve body from being inclined with respect to the axis during the opening / closing valve, and to stabilize the operation of the second check valve. Brake feeling can be improved.
According to the pneumatic booster of the second aspect, the entire length of the second check valve (the length in the passage axial direction) is shortened, and the check valve can be downsized.
According to the pneumatic booster of claim 3, for example, when the valve body of the second check valve is formed of synthetic resin, and the divided valve bodies are joined and integrated by welding It is possible to minimize the influence of heat on the valve seat and the guide portion during welding, and to ensure the quality of the check valve.
According to the pneumatic booster of the fourth aspect of the present invention, compared with the case where a throttle passage having a very small hole diameter is formed in the valve body of the second check valve over the entire length of the valve body, Manufacturing is easy and manufacturing costs can be reduced.
According to the pneumatic booster of the fifth aspect, the piping between the constant pressure chamber and the negative pressure source can be simplified.
According to the check valve with throttle for a pneumatic booster according to claim 6, it is possible to prevent the valve body from being inclined with respect to the axis at the time of opening and closing the valve, and to stabilize the operation of the check valve. As a result, it is possible to improve the brake feeling of a brake system having a pneumatic booster configured using the check valve.

本発明の一実施形態を図１および図２に基いて説明する。
図１に示されるように、本実施形態の気圧式倍力装置は、フロントシェル１とリアシェル２とによって内部が密閉された倍力装置本体３が形成される。該倍力装置本体３は、パワーピストンユニット４によって、前側（図１における左側）に配置される定圧室５と後側（図１における右側）に配置される変圧室６とに画成される。パワーピストンユニット４は、外周端部がシェル１およびシェル２によって密閉されたダイヤフラム７と、定圧室５側に配置されてダイヤフラム７の表面に接する薄板状のパワーピストン８と、ダイヤフラム７およびパワーピストン８の内周端部が気密に固着されて倍力装置本体３に対して軸方向（図１における左右方向）へ変位可能に設けられるバルブボディ９と、によって概略が構成される。なお、非作動状態（ブレーキペダルが操作されていない状態）では、パワーピストンユニット４は、リターンスプリング１０によって後方（図１における右方向）へ付勢される。 An embodiment of the present invention will be described with reference to FIGS. 1 and 2.
As shown in FIG. 1, the pneumatic booster of the present embodiment includes a booster body 3 whose inside is sealed by a front shell 1 and a rear shell 2. The booster body 3 is defined by a power piston unit 4 into a constant pressure chamber 5 disposed on the front side (left side in FIG. 1) and a variable pressure chamber 6 disposed on the rear side (right side in FIG. 1). . The power piston unit 4 includes a diaphragm 7 whose outer peripheral end is sealed by the shell 1 and the shell 2, a thin plate-like power piston 8 disposed on the constant pressure chamber 5 side and in contact with the surface of the diaphragm 7, the diaphragm 7 and the power piston An outline is constituted by a valve body 9 in which an inner peripheral end of 8 is fixed in an airtight manner so as to be displaceable in the axial direction (left-right direction in FIG. 1) with respect to the booster main body 3. In a non-operating state (a state where the brake pedal is not operated), the power piston unit 4 is urged rearward (rightward in FIG. 1) by the return spring 10.

バルブボディ９は、倍力装置本体３の後端部に対して後方（図１における右方向）へ突出された部分が円筒状に形成される。また、バルブボディ９には、前側端面に大径孔部１１と小径孔部１２とが同軸配置されており、大径孔部１１には、出力軸１３の基端部分に形成されたフランジ部１４がリアクションディスク１５を介して嵌合される。さらに、小径孔部１２には、プランジャ１６が摺動可能に嵌合されており、該プランジャ１６の後端部には入力軸１７が接続される。   The valve body 9 is formed in a cylindrical shape at a portion protruding rearward (rightward in FIG. 1) with respect to the rear end portion of the booster body 3. The valve body 9 has a large-diameter hole 11 and a small-diameter hole 12 coaxially arranged on the front end face. 14 is fitted through the reaction disk 15. Further, a plunger 16 is slidably fitted into the small diameter hole portion 12, and an input shaft 17 is connected to the rear end portion of the plunger 16.

バルブボディ９の円筒部分の内部には、ポペット弁１８が設けられる。該ポペット弁１８は、後端部がスプリング受け１９によってバルブボディ９の内周面に固定されており、前端部は中間部の蛇腹形状によって前後方向（図１における左右方向）へ進退可能になっている。なお、ポペット弁１８は、前端部が、スプリング受け１９との間に介装されたスプリング２０によって前方（図１における左方向）へ付勢される。また、入力軸１７は、当該入力軸１７のフランジ部２１とスプリング受け１９との間に介装されたスプリング２２によって、後方へ付勢される。   A poppet valve 18 is provided inside the cylindrical portion of the valve body 9. The poppet valve 18 has a rear end portion fixed to the inner peripheral surface of the valve body 9 by a spring receiver 19, and the front end portion can be advanced and retracted in the front-rear direction (left-right direction in FIG. 1) by the bellows shape of the intermediate portion. ing. The poppet valve 18 is urged forward (to the left in FIG. 1) by a spring 20 interposed between the poppet valve 18 and the spring receiver 19. The input shaft 17 is urged rearward by a spring 22 interposed between the flange portion 21 of the input shaft 17 and the spring receiver 19.

また、バルブボディ９には、当該バルブボディ９の内部と定圧室５とを連通させる通路２３と、当該バルブボディ９の内部と変圧室６とを連通させる通路２４とが形成される。バルブボディ９の内部は、後端部に設けられたフィルタ２５を介して大気に連通される。バルブボディ９の内周面には、ポペット弁１８が着座される弁座２６が形成されて、該弁座２６にポペット弁１８の前端部が着座することにより通路２３が遮断される。また、プランジャ１６の後端部には、ポペット弁１８が着座される弁座２７が形成されて、該弁座２７にポペット弁１８が着座することにより通路２４が遮断される。負圧源（本実施形態ではインテークマニホールド）に接続される通路２８は、フロントシェル１に設けられた負圧導入管２９に接続される。これにより、定圧室５は大気に対して負圧になる。   Further, the valve body 9 is formed with a passage 23 that communicates the inside of the valve body 9 with the constant pressure chamber 5 and a passage 24 that communicates the interior of the valve body 9 and the variable pressure chamber 6. The interior of the valve body 9 is communicated with the atmosphere via a filter 25 provided at the rear end. A valve seat 26 on which the poppet valve 18 is seated is formed on the inner peripheral surface of the valve body 9, and the passage 23 is blocked when the front end portion of the poppet valve 18 is seated on the valve seat 26. Further, a valve seat 27 on which the poppet valve 18 is seated is formed at the rear end portion of the plunger 16, and the passage 24 is blocked by the poppet valve 18 seated on the valve seat 27. A passage 28 connected to a negative pressure source (intake manifold in the present embodiment) is connected to a negative pressure introduction pipe 29 provided in the front shell 1. Thereby, the constant pressure chamber 5 becomes a negative pressure with respect to the atmosphere.

通路２８には、定圧室５側から負圧源側への気体の流動のみが許容される第１の逆止弁３０が設けられる。第１の逆止弁３０は、弁ばね３１の設定荷重がF1に設定されており、該弁ばね３１のばね力によって弁体３２が弁本体４４に形成された弁座３３に着座される。そして、第１の逆止弁３０は、入口３４側と出口３５側との圧力差が開弁圧力P1に到達した時点で、弁体３２が弁座３３から離間して開弁される。   The passage 28 is provided with a first check valve 30 that allows only gas flow from the constant pressure chamber 5 side to the negative pressure source side. In the first check valve 30, the set load of the valve spring 31 is set to F1, and the valve body 32 is seated on the valve seat 33 formed in the valve main body 44 by the spring force of the valve spring 31. When the pressure difference between the inlet 34 side and the outlet 35 side reaches the valve opening pressure P1, the first check valve 30 is opened while the valve body 32 is separated from the valve seat 33.

第１の逆止弁３０と負圧導入管２９との間の通路３６には、第１の逆止弁３０に対して直列に配置されて該第１の逆止弁３０と同一方向への気体の流動のみが許容される第２の逆止弁３７が設けられる。該第２の逆止弁３７は、弁本体４５が、入口４１側（定圧室５側、図２における右側）を形成する弁分割体４６と出口４２側（負圧源側、図２における左側）を形成する弁分割体４７とに２分割されて構成される。入口４１側の弁分割体４６は、有底円筒状に形成されて弁体３９を収容する胴部４９と、該胴部４９の底部に開口した通路を有する接続部５０と、によって構成される。   A passage 36 between the first check valve 30 and the negative pressure introduction pipe 29 is arranged in series with respect to the first check valve 30 and extends in the same direction as the first check valve 30. A second check valve 37 that allows only gas flow is provided. In the second check valve 37, the valve main body 45 has a valve divided body 46 forming an inlet 41 side (constant pressure chamber 5 side, right side in FIG. 2) and an outlet 42 side (negative pressure source side, left side in FIG. 2). ), And is divided into two parts. The valve split body 46 on the inlet 41 side is configured by a body portion 49 that is formed in a bottomed cylindrical shape and accommodates the valve body 39, and a connection portion 50 that has a passage opened at the bottom of the body portion 49. .

弁分割体４６には、胴部４９の出口４２側の開口端部にフランジ部５１が形成されており、弁分割体４７の軸部５２を弁分割体４６の胴部４９の内周面に嵌合させて、弁分割体４６のフランジ部５１と弁分割体４７の軸部５２の基端部に形成されたフランジ部５３とを当接させる。そして、弁分割体４６のフランジ部５１と出口４２側の弁分割体４７のフランジ部５３とを溶着させて接合することにより、弁分割体４６と弁分割体４７とが一体化されて、弁本体４５が形成される。なお、弁分割体４６および弁分割体４７は合成樹脂を成形することにより形成される。   The valve split body 46 is formed with a flange portion 51 at the opening end of the trunk portion 49 on the outlet 42 side, and the shaft portion 52 of the valve split body 47 is formed on the inner peripheral surface of the trunk portion 49 of the valve split body 46. The flange part 51 of the valve | bulb division body 46 and the flange part 53 formed in the base end part of the axial part 52 of the valve | bulb division body 47 are contact | abutted by making it fit. Then, the valve split body 46 and the valve split body 47 are integrated by welding the flange portion 51 of the valve split body 46 and the flange portion 53 of the valve split body 47 on the outlet 42 side, and the valve split body 47 is integrated. A main body 45 is formed. The valve segment 46 and the valve segment 47 are formed by molding a synthetic resin.

弁本体４５（弁分割体４７）の胴部４９の内周面には、ガイド部５４が形成されており、このガイド部５４には、円柱状に形成された弁体３９が軸方向（通路軸方向、図２における左右方向）へ摺動可能に案内される。また、弁体３９の入口４１側（図２における右側）の端面には、シート保持部５６によって保持されるシート部５５が設けられる。弁体３９と弁分割体４７との間には、弁ばね３８が介装される。該弁ばね３８は、入口４１側（図２における右側）が、弁体３９の出口４２側（図２における左側）の端面に凹状に形成されたばね収容部４８に収容される。弁体３９のばね収容部４８の底部には、段階的に縮径して形成されるオリフィス４３（絞り通路）が設けられており、該オリフィス４３によって第２の逆止弁３７の入口４１側の通路と出口４２側の通路とが常時連通される。また、弁体３９の外周面には、第２の逆止弁３７の入口４１側の通路と出口４２側の通路とを連通させる通路溝５８が形成される。   A guide portion 54 is formed on the inner peripheral surface of the body portion 49 of the valve main body 45 (valve divided body 47), and a valve body 39 formed in a cylindrical shape is axially (passage) in the guide portion 54. It is guided so as to be slidable in the axial direction (left and right direction in FIG. 2). Further, a seat portion 55 that is held by a seat holding portion 56 is provided on the end surface of the valve body 39 on the inlet 41 side (right side in FIG. 2). A valve spring 38 is interposed between the valve body 39 and the valve split body 47. The valve spring 38 is accommodated in a spring accommodating portion 48 formed in a concave shape on the end surface on the outlet 42 side (left side in FIG. 2) of the valve body 39 on the inlet 41 side (right side in FIG. 2). At the bottom of the spring accommodating portion 48 of the valve body 39, an orifice 43 (throttle passage) formed by reducing the diameter in stages is provided, and the orifice 43 side of the second check valve 37 is provided by the orifice 43. And the passage on the outlet 42 side are always in communication. Further, a passage groove 58 is formed on the outer peripheral surface of the valve body 39 to communicate the passage on the inlet 41 side and the passage on the outlet 42 side of the second check valve 37.

第２の逆止弁３７は、弁ばね３８の設定荷重がF2に設定されており、該弁ばね３８のばね力によって弁体３９が弁本体４５に形成された弁座４０に着座される。そして、第２の逆止弁３７は、入口４１側と出口４２側との圧力差が開弁圧力P2に到達した時点で、弁体３９が弁座４０から離間して開弁される。また、第２の逆止弁３７の弁ばね３８の設定荷重F2は第１の逆止弁３０の弁ばね３１の設定荷重F1よりも大きく設定されており（F2＞F1）、第２の逆止弁３７は、第１の逆止弁３０の圧力差P1よりも大きな圧力差P2（P2＞P1）を以って開弁される。   In the second check valve 37, the set load of the valve spring 38 is set to F 2, and the valve body 39 is seated on the valve seat 40 formed in the valve body 45 by the spring force of the valve spring 38. When the pressure difference between the inlet 41 side and the outlet 42 side reaches the valve opening pressure P <b> 2, the second check valve 37 is opened by separating the valve body 39 from the valve seat 40. The set load F2 of the valve spring 38 of the second check valve 37 is set larger than the set load F1 of the valve spring 31 of the first check valve 30 (F2> F1), and the second reverse The stop valve 37 is opened with a pressure difference P2 (P2> P1) larger than the pressure difference P1 of the first check valve 30.

次に、本実施形態の作用を説明する。
ブレーキペダルを踏み込むと、入力軸１７が前進（図１における左方向へ移動）する。これにより、プランジャ１６の弁座２７がポペット弁１８から離間されて、大気が通路２４から変圧室６へ導入される。この時、定圧室５は大気圧に対して負圧であるため、定圧室５と変圧室６との間に圧力差が生じて、パワーピストンユニット４がリターンスプリング１０を圧縮するようにして前進することにより、倍力された力が出力軸１３から出力される。そして、パワーピストンユニット４が前進するのに伴って定圧室５の容積が小さくなり、定圧室５の圧力が上昇すると、第１の逆止弁３０および第２の逆止弁３７がそれぞれ開弁して、定圧室５を元の圧力状態（ブレーキペダルを操作する前の圧力状態）に回復させる。 Next, the operation of this embodiment will be described.
When the brake pedal is depressed, the input shaft 17 moves forward (moves leftward in FIG. 1). As a result, the valve seat 27 of the plunger 16 is separated from the poppet valve 18, and the atmosphere is introduced from the passage 24 into the variable pressure chamber 6. At this time, since the constant pressure chamber 5 is negative with respect to the atmospheric pressure, a pressure difference is generated between the constant pressure chamber 5 and the variable pressure chamber 6 so that the power piston unit 4 compresses the return spring 10 and moves forward. By doing so, the boosted force is output from the output shaft 13. When the volume of the constant pressure chamber 5 decreases as the power piston unit 4 moves forward and the pressure in the constant pressure chamber 5 increases, the first check valve 30 and the second check valve 37 are opened. Then, the constant pressure chamber 5 is restored to the original pressure state (pressure state before operating the brake pedal).

ここで、ブレーキの制動力を一定に保持するためにブレーキペダルの踏み込みを停止させると、負圧源側の圧力と定圧室５側の圧力との圧力差が減少して、その圧力差がP2に到達した時点で、第２の逆止弁３７が開弁する。この時、第２の逆止弁３７の弁体３９は、弁ばね３８を圧縮するようにして、外周面が弁本体４５の内周面に形成されたガイド部５４によって軸方向（通路軸方向、図２における左方向）へ案内されながら移動する。第２の逆止弁３７が開弁されることで、第２の逆止弁３７の弁体３９のオリフィス４３および通路溝５８だけで負圧源と定圧室５とが連通される。これにより、定圧室５の圧力はゆっくりと低下して、これに伴い、パワーピストンユニット４が徐々に前進して出力を上昇させる。この状態では、第１の逆止弁３０の入口３４側の圧力が次第に上昇して当該入口３４側の圧力と出口３５側の圧力との圧力差がP1以上であり、第１の逆止弁３０は開弁された状態にある。   Here, when the depression of the brake pedal is stopped to keep the braking force of the brake constant, the pressure difference between the pressure on the negative pressure source side and the pressure on the constant pressure chamber 5 side decreases, and the pressure difference becomes P2 The second check valve 37 is opened at the point of time when the value is reached. At this time, the valve body 39 of the second check valve 37 compresses the valve spring 38 so that the outer peripheral surface is axially formed by the guide portion 54 formed on the inner peripheral surface of the valve main body 45 (the passage axial direction). , And moves while being guided in the left direction in FIG. By opening the second check valve 37, the negative pressure source and the constant pressure chamber 5 are communicated only by the orifice 43 and the passage groove 58 of the valve body 39 of the second check valve 37. As a result, the pressure in the constant pressure chamber 5 slowly decreases, and the power piston unit 4 gradually advances and increases the output accordingly. In this state, the pressure on the inlet 34 side of the first check valve 30 gradually increases, and the pressure difference between the pressure on the inlet 34 side and the pressure on the outlet 35 side is P1 or more, and the first check valve 30 is in the opened state.

そして、入口３４側の圧力と出口３５側の圧力との圧力差がP1よりも小さくなった時点で第１の逆止弁３０が開弁して、負圧源と定圧室５との連通が遮断されることにより、最終的に、ブレーキの制動力が一定に保持されることになる。   When the pressure difference between the pressure on the inlet 34 side and the pressure on the outlet 35 side becomes smaller than P1, the first check valve 30 opens, and the communication between the negative pressure source and the constant pressure chamber 5 is established. By shutting off, the braking force of the brake is finally held constant.

この実施形態では以下の効果を奏する。
本実施形態によれば、定圧室５と負圧源とを接続させる通路に、開弁圧力P1の第１の逆止弁３０と開弁圧力P2の第２の逆止弁３７とを直列に配設して、第２の逆止弁３７にその入口４１側と出口４２側とを常時連通させるオリフィス４３（絞り通路）を設けたので、ブレーキの制動力を一定に保持するためにブレーキペダルの踏み込みを途中で停止した場合であっても、第２の逆止弁３７の開弁圧力P2によって生じる入口４１側と出口４２側との圧力差によって、オリフィス４３を介して徐々に定圧室５の圧力を低下させて出力を徐々に上昇させることにより、ブレーキフィーリングを向上させることができる。
本実施形態によれば、第２の逆止弁３７の弁体３９の外周面が弁本体４５の内周面に形成されたガイド部５４によって軸方向（通路軸方向）へ案内されるので、弁体３９が軸線に対して傾くのを防止して、第２の逆止弁３７の動作を安定させることができる。
また、本実施形態によれば、第２の逆止弁３７の弁ばね３８が、弁体３９に形成された凹状のばね収容部４８（弁体内部）に収容されるので、第２の逆止弁３７の全長（通路軸方向長さ）が短縮されて当該逆止弁３７を小型化することができる。
また、本実施形態によれば、第２の逆止弁３７の入口４１側（定圧室５側）の弁分割体４６と出口４２側（負圧源側）の弁分割体４７とのそれぞれが、弁座４０から離れた位置で溶着されて接合されることで一体化されるので、溶着時における弁座４０への熱影響を最小限に抑制することが可能になり、当該逆止弁３７の動作を保証して品質を確保することができる。
また、本実施形態によれば、第２の逆止弁３７の弁体３９に形成されるオリフィス４３（絞り通路）を段付孔によって構成したので、第２の逆止弁３７の弁体３９に極めて小さい孔径のオリフィス４３（絞り通路）を通しで形成する場合と比較して、当該弁体３９の製造が容易であり、製造コストを削減することができる。 This embodiment has the following effects.
According to this embodiment, the first check valve 30 having the valve opening pressure P1 and the second check valve 37 having the valve opening pressure P2 are connected in series to the passage connecting the constant pressure chamber 5 and the negative pressure source. Since the second check valve 37 is provided with the orifice 43 (throttle passage) that always communicates the inlet 41 side and the outlet 42 side with the second check valve 37, the brake pedal is used to keep the braking force of the brake constant. Even when the stepping of the valve is stopped halfway, the constant pressure chamber 5 is gradually passed through the orifice 43 due to the pressure difference between the inlet 41 side and the outlet 42 side caused by the valve opening pressure P2 of the second check valve 37. The brake feeling can be improved by lowering the pressure and gradually increasing the output.
According to the present embodiment, the outer peripheral surface of the valve body 39 of the second check valve 37 is guided in the axial direction (passage axial direction) by the guide portion 54 formed on the inner peripheral surface of the valve body 45. The valve body 39 can be prevented from being inclined with respect to the axis, and the operation of the second check valve 37 can be stabilized.
Further, according to the present embodiment, the valve spring 38 of the second check valve 37 is accommodated in the concave spring accommodating portion 48 (inside the valve element) formed in the valve element 39, so that the second reverse valve The overall length of the check valve 37 (the length in the passage axial direction) is shortened, and the check valve 37 can be downsized.
Further, according to the present embodiment, each of the valve divided body 46 on the inlet 41 side (constant pressure chamber 5 side) and the valve divided body 47 on the outlet 42 side (negative pressure source side) of the second check valve 37 is provided. Since they are integrated by being welded and joined at a position away from the valve seat 40, it is possible to minimize the influence of heat on the valve seat 40 during welding, and the check valve 37 The operation can be guaranteed to ensure the quality.
In addition, according to the present embodiment, the orifice 43 (throttle passage) formed in the valve body 39 of the second check valve 37 is configured by the stepped hole, so that the valve body 39 of the second check valve 37 is formed. Compared with the case where the orifice 43 (throttle passage) having a very small hole diameter is formed through the valve body 39, the valve body 39 can be easily manufactured and the manufacturing cost can be reduced.

なお、実施形態は上記に限定されるものではなく、例えば次のように構成してもよい。
図３に示されるように、図１に示される実施形態において直列に配置される第１の逆止弁３０と第２の逆止弁３７とを同一のハウジングに配置して一体化させた逆止弁６１を用いて気圧式倍力装置を構成してもよい。この場合、第２の逆止弁３７の出口６３側に第１の逆止弁３０が構成される。該第１の逆止弁３０は、円板状に形成された弾性体からなる弁体６４が、その弾性力によって弁座６５に着座される。なお、図３において、図１に示される実施形態に対して同一又は相当する構成要素には同一の符号を付与して、その詳細な説明を省略する。ここで、符号６６は弁体６４を出口６３側から支持する支持部材、符号６７は弁体６４の中心の孔に嵌着された軸部材である。
この実施形態によれば、通路に単独で直列に配置されていた第１の逆止弁３０と第２の逆止弁３７とが一つの逆止弁６１に集約されるので、定圧室５と負圧源との間の配管を簡易化することができる。 In addition, embodiment is not limited above, For example, you may comprise as follows.
As shown in FIG. 3, the first check valve 30 and the second check valve 37 arranged in series in the embodiment shown in FIG. 1 are arranged in the same housing and integrated. A pneumatic booster may be configured using the stop valve 61. In this case, the first check valve 30 is configured on the outlet 63 side of the second check valve 37. In the first check valve 30, a valve body 64 made of an elastic body formed in a disc shape is seated on the valve seat 65 by its elastic force. In FIG. 3, the same reference numerals are given to the same or corresponding components in the embodiment shown in FIG. 1, and detailed description thereof is omitted. Here, reference numeral 66 denotes a support member that supports the valve body 64 from the outlet 63 side, and reference numeral 67 denotes a shaft member that is fitted into the central hole of the valve body 64.
According to this embodiment, since the first check valve 30 and the second check valve 37 that are arranged in series alone in the passage are integrated into one check valve 61, the constant pressure chamber 5 and The piping between the negative pressure source can be simplified.

本実施形態の気圧式倍力装置の全体を示す縦断面図である。It is a longitudinal section showing the whole pneumatic pressure booster of this embodiment. 本実施形態の気圧式倍力装置の第２の逆止弁の縦断面図である。It is a longitudinal cross-sectional view of the 2nd non-return valve of the pneumatic booster of this embodiment. 他の実施形態の気圧式倍力装置の逆止弁の縦断面図である。It is a longitudinal cross-sectional view of the check valve of the pneumatic booster of other embodiment.

符号の説明Explanation of symbols

３ 倍力装置本体、４ パワーピストンユニット、５ 定圧室、６ 変圧室、３７ 第２の逆止弁、３８ 弁ばね、３９ 弁体、４０ 弁座、４１ 入口、４２ 出口、４３ オリフィス（絞り通路）、４８ ばね収容部（弁体内部）、５０ 接続部、５４ ガイド部 3 Booster body 4 Power piston unit 5 Constant pressure chamber 6 Transformer chamber 37 Second check valve 38 Valve spring 39 Valve body 40 Valve seat 41 Inlet 42 Outlet 43 Orifice (throttle passage) ), 48 Spring accommodating part (inside valve body), 50 connection part, 54 guide part

Claims (6)

倍力装置本体内を出力軸が取付けられたパワーピストンユニットによって定圧室と変圧室とに画成し、前記定圧室を負圧源に接続し、前記定圧室と前記負圧源とを接続する通路に、それぞれ所定の開弁圧力が設定されて前記定圧室側から前記負圧源側への気体の流動のみを許容する第１および第２の逆止弁を直列に、かつ、第２の逆止弁が前記定圧室側となるように配設し、さらに、前記第２の逆止弁の前記定圧室側と前記負圧源側とを常時連通する絞り通路を設けると共に、前記変圧室に大気を導入して前記定圧室と前記変圧室とに圧力差を生じさせて前記パワーピストンユニットを前記出力軸側へ移動させ、前記出力軸から倍力させた力を出力させる気圧式倍力装置において、
前記第２の逆止弁は、前記通路に接続される弁本体と該弁本体内を移動する弁体とからなり、前記弁本体の内周面に形成される弁座に対して前記負圧源側に、前記弁体を通路軸方向へ案内するガイド部を有することを特徴とする気圧式倍力装置。 The booster body is divided into a constant pressure chamber and a variable pressure chamber by a power piston unit to which an output shaft is attached. The constant pressure chamber is connected to a negative pressure source, and the constant pressure chamber and the negative pressure source are connected. First and second check valves, each of which has a predetermined valve opening pressure set in the passage and allows only the gas flow from the constant pressure chamber side to the negative pressure source side, are connected in series, and the second The check valve is disposed so as to be on the constant pressure chamber side, and further provided with a throttle passage that always communicates the constant pressure chamber side of the second check valve with the negative pressure source side, and the variable pressure chamber Pneumatic booster that introduces air into the constant pressure chamber and the variable pressure chamber to cause a pressure difference to move the power piston unit to the output shaft side and output a boosted force from the output shaft In the device
The second check valve includes a valve body connected to the passage and a valve body that moves in the valve body, and the negative pressure is applied to a valve seat formed on an inner peripheral surface of the valve body. A pneumatic booster having a guide portion on the source side for guiding the valve body in a passage axial direction. 前記第２の逆止弁は、前記弁体を前記弁座へ向けて付勢する弁ばねを前記弁体内部に収容することを特徴とする請求項１に記載の気圧式倍力装置。 2. The pneumatic booster according to claim 1, wherein the second check valve houses a valve spring that urges the valve body toward the valve seat inside the valve body. 前記第２の逆止弁は、前記弁本体が前記定圧室側と前記負圧源側とに分割して構成され、分割された前記弁本体の接合部が前記弁本体の前記負圧源側に形成されることを特徴とする請求項１又は２に記載の気圧式倍力装置。 The second check valve is configured such that the valve body is divided into the constant pressure chamber side and the negative pressure source side, and the joint portion of the divided valve body is the negative pressure source side of the valve body. The pneumatic booster according to claim 1 or 2, wherein the pneumatic booster is formed as follows. 前記絞り通路は、前記第２の逆止弁の前記弁体の段付孔によって形成されることを特徴とする請求項１〜３のいずれかに記載の気圧式倍力装置。 4. The pneumatic booster according to claim 1, wherein the throttle passage is formed by a stepped hole of the valve body of the second check valve. 前記第１の逆止弁と前記第２の逆止弁とが一のハウジングにより一体に構成されることを特徴とする請求項１に記載の気圧式倍力装置。 The pneumatic booster according to claim 1, wherein the first check valve and the second check valve are integrally formed by a single housing. 気圧式倍力装置の定圧室と負圧源とを接続する通路に設けられ、前記定圧室側から前記負圧源側への気体の流動のみを許容して、前記定圧室側と前記負圧源側とを常時連通する絞り通路を備える気圧式倍力装置用絞り付逆止弁において、
弁座が設けられて前記通路に接続される弁本体と、該弁本体に収容される弁体とによって構成され、前記弁本体の前記弁座に対して前記負圧源側に前記弁体を通路軸方向へ案内するガイド部が設けられることを特徴とする気圧式倍力装置用絞り付逆止弁。 Provided in a passage connecting the constant pressure chamber and the negative pressure source of the pneumatic booster, allowing only the flow of gas from the constant pressure chamber side to the negative pressure source side, the constant pressure chamber side and the negative pressure In a check valve with a throttle for a pneumatic booster having a throttle passage that always communicates with the source side,
A valve body provided with a valve seat and connected to the passage, and a valve body accommodated in the valve body, and the valve body on the negative pressure source side with respect to the valve seat of the valve body A check valve with throttle for a pneumatic booster, characterized in that a guide portion for guiding in the axial direction of the passage is provided.
JP2007146204A 2007-05-31 2007-05-31 Pneumatic booster and check valve with throttling for pneumatic booster Pending JP2008296788A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104309431A (en) * 2014-10-15 2015-01-28 雷东玉 T-shaped inverted triangular servo electro-tricycle

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Publication number Priority date Publication date Assignee Title
JPS57122465A (en) * 1981-01-23 1982-07-30 Hitachi Metals Ltd Developing deveice for magnetic toner
JPS5879460A (en) * 1981-11-02 1983-05-13 Nippon Densan Kk Brushless motor
JPS60183661A (en) * 1984-03-02 1985-09-19 Nec Corp Information processing unit
JP2662675B2 (en) * 1988-03-31 1997-10-15 トキコ株式会社 Pneumatic booster
JP2001099338A (en) * 1999-09-29 2001-04-10 Daikin Ind Ltd Check valve

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57122465A (en) * 1981-01-23 1982-07-30 Hitachi Metals Ltd Developing deveice for magnetic toner
JPS5879460A (en) * 1981-11-02 1983-05-13 Nippon Densan Kk Brushless motor
JPS60183661A (en) * 1984-03-02 1985-09-19 Nec Corp Information processing unit
JP2662675B2 (en) * 1988-03-31 1997-10-15 トキコ株式会社 Pneumatic booster
JP2001099338A (en) * 1999-09-29 2001-04-10 Daikin Ind Ltd Check valve

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104309431A (en) * 2014-10-15 2015-01-28 雷东玉 T-shaped inverted triangular servo electro-tricycle

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