JPH02248703A - Hydraulic pressure valve with pressure compensation - Google Patents

Abstract

PURPOSE:To facilitate working for a valve main body by detecting pressures in the first and second operating ports respectively by check valves to decide the set pressures of the first and second pressure compensation valves and controlling the hydraulic pressure to one of the first and second operating ports. CONSTITUTION:When the pilot oil pressure is introduced in the first pressure receiving chamber 261 to move a spool 12 to the left, the discharge hydraulic pressure liquid of a pump 22 flows through the first pressure compensation valve 28 and the first operating port 18 to move a hydraulic actuator 23 to the left. At this time, the discharge hydraulic pressure separates a poppet valve 31 from the valve seat of a checking valve 32 to flow in the first port 16, and the load pressure is introduced into a pore 35, a back pressure chamber 34, a liquid hole 36, a pressure receiving chamber 37 and a pressure introduction port 39. In this case, however, as the load pressure is introduced from the outer hydraulic pressure valve with pressure compensation into the port 39, one higher load pressure is set on the first pressure compensation valve 28. The same operation is conducted to the second pressure compensation valve 30. Thus, the working for a valve main body 10 can be facilitated, and furthermore, the first and second operating ports 18, 19 can be set at different values of pressure.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、パワーショベルの液圧回路等に設けられる圧
力補償付液圧弁に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a hydraulic valve with pressure compensation provided in a hydraulic circuit of a power shovel, etc.

〔従来の技術〕[Conventional technology]

パワーショベルは旋回モータ、走行モータ、ブームシリ
ンダ、アームシリンダ、パケットシリンダ等の複数の液
圧アクチュエータを備えているので、その液圧回路は各
液圧アクチュエータに液圧を供給する複数の液圧弁を備
えている。Since a power excavator is equipped with multiple hydraulic actuators such as a swing motor, a travel motor, a boom cylinder, an arm cylinder, and a packet cylinder, its hydraulic circuit has multiple hydraulic valves that supply hydraulic pressure to each hydraulic actuator. We are prepared.

このように、複数の液圧弁を備えた液圧回路においては
、２つ以上の液圧弁を同時操作すると負荷圧の低い液圧
アクチュエータに液圧が供給されて負荷の高い液圧アク
チュエータには液圧が供給されなくなる。In this way, in a hydraulic circuit equipped with multiple hydraulic valves, when two or more hydraulic valves are operated simultaneously, hydraulic pressure is supplied to the hydraulic actuator with a low load pressure, and hydraulic pressure is supplied to the hydraulic actuator with a high load. Pressure is no longer supplied.

そこで、特開昭６０−１８８６０４号公報に示す圧力補
償付液圧弁が提案されている。Therefore, a hydraulic valve with pressure compensation has been proposed as disclosed in Japanese Patent Application Laid-Open No. 188604/1983.

つまり、第４図に示すように、弁本体１にスプール２を
設けて入口ポート３．４を作動ボ−ト５．６に連通−遮
断し、その作動ポート５゜６と連通・遮断されるブリッ
ジ通路７に圧力補償弁を設ける゛と共に、その圧力補償
弁を複数の液圧弁における最高作動圧によってセットさ
れるように構成して、複数の圧力補償付液圧弁の作動ポ
ート５，６に均一な流量が流れるようにしてあり、この
ようにすることで複数の液圧アクチュエータを同時操作
した時に負荷圧が異なってもそれぞれの液圧アクチュエ
ータに均一な流量を供給できる。That is, as shown in FIG. 4, a spool 2 is provided on the valve body 1 to communicate and cut off the inlet port 3.4 to the operating boat 5.6, and communicate and cut off the inlet port 5.6 to the operating port 5.6. A pressure compensating valve is provided in the bridge passage 7, and the pressure compensating valve is configured to be set by the highest operating pressure of the plurality of hydraulic valves, so that the pressure compensating valve is set uniformly to the operating ports 5 and 6 of the plurality of hydraulic pressure valves with pressure compensation. By doing so, even if the load pressures differ when a plurality of hydraulic actuators are operated simultaneously, a uniform flow rate can be supplied to each hydraulic actuator.

〔発明が解決しようとする課題〕[Problem to be solved by the invention]

かかる圧力補償付液圧弁において、作動ポート５．６の
圧力を圧力補償弁に導くために弁本体１１；０字状のブ
リッジ通路７を形成しているので、その弁本体１の製作
・加工が大変な面倒となると共に、ブリッジ通路７と作
動ポート５゜６をスプール２で連通・遮断しているので
、スプール２が中立位置の時に作動ポート５，６がスプ
ール２と弁孔８との間よりタンク側に洩れることがあり
、液圧アクチュエータが微動してしまうことがある。In such a hydraulic pressure valve with pressure compensation, the valve body 11 is formed with a O-shaped bridge passage 7 in order to guide the pressure of the operating port 5.6 to the pressure compensation valve, so the manufacture and processing of the valve body 1 is easy. This is very troublesome, and since the bridge passage 7 and the operating ports 5 and 6 are communicated and blocked by the spool 2, the operating ports 5 and 6 are connected between the spool 2 and the valve hole 8 when the spool 2 is in the neutral position. This may cause leakage to the tank side, causing the hydraulic actuator to move slightly.

そこで、本発明は前述の課題を解決できるようにした圧
力補償付液圧弁を提供することを目的とする。SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a hydraulic valve with pressure compensation that can solve the above-mentioned problems.

〔課題を解決するための手段及び作用〕第１・第２作動
ポートの圧力を検出する２つのチエツク弁と、その検出
した圧力により圧力をセットする２つの圧力補償弁をそ
れぞれ設けた圧力補償式液圧弁であり、 これによって、弁本体に複雑形状の溝を形成しなくとも
良いと共に、スプール中立時に第１・第２作動ポートよ
りタンク側への液洩れがなく、しかも第１・第２作動ポ
ートの圧力を別々にセットできる。[Means and actions for solving the problem] A pressure compensation type equipped with two check valves that detect the pressure of the first and second operating ports, and two pressure compensation valves that set the pressure based on the detected pressure. This is a hydraulic valve, which eliminates the need to form a complicated groove in the valve body, prevents liquid from leaking from the first and second actuating ports to the tank side when the spool is in the neutral position, and also prevents liquid from leaking from the first and second actuating ports to the tank side. Port pressure can be set separately.

〔実　施　例〕〔Example〕

第１図に示すように、弁本体１０の弁孔１１にスプール
１２が嵌押され。その弁孔１１の軸方向中間に出口ポー
ト１３が形成しであると共に、この出口ポート１３の両
側に第１・第２ポンプポート１４，１５、第１・第２ポ
ート１６゜１７、第１−第２作動ポート１８，１９、第
１・第２タンクポート２０，２１がそれぞれ形成され、
第１・第２ポンプポート１４，１５は液圧ポンプ２２の
吐出側に連通し、第１−第２作動ポート１８．１９は液
圧アクチュエータ２３の第１・第２室２３１，２３２に
連通し、第１拳第２タンクポート２０．２１はタンク２
４にそれぞれ連通している。As shown in FIG. 1, the spool 12 is fitted into the valve hole 11 of the valve body 10. An outlet port 13 is formed in the axial middle of the valve hole 11, and on both sides of the outlet port 13 there are first and second pump ports 14, 15, first and second ports 16°17, Second operating ports 18, 19, first and second tank ports 20, 21 are formed, respectively.
The first and second pump ports 14 and 15 communicate with the discharge side of the hydraulic pump 22, and the first and second operating ports 18 and 19 communicate with the first and second chambers 231 and 232 of the hydraulic actuator 23. , the first fist second tank port 20.21 is the tank 2
4 are connected to each other.

前記スプール１２はスブリンーグ２５で各ポートを遮断
する中立位置に保持され、第１受圧室２６、又は第２受
圧室２６２にパイロット圧が供給されると中立位置より
左右に移動して第１・第２位置となる。The spool 12 is held at a neutral position where each port is blocked by a subring 25, and when pilot pressure is supplied to the first pressure receiving chamber 26 or the second pressure receiving chamber 262, it moves from the neutral position to the left and right to close the first and second pressure receiving chambers. This will be the 2nd position.

前記出口ポート１３と第１ポート１６を連通ずる第１通
路２７には第１圧力補償弁２８が設けであると共に、出
口ポート１３と第２ポート１７を連通ずる第２通路２９
には第２圧力補償弁３０が設けである。A first passage 27 that communicates between the outlet port 13 and the first port 16 is provided with a first pressure compensating valve 28, and a second passage 29 that communicates between the outlet port 13 and the second port 17 is provided.
A second pressure compensating valve 30 is provided.

前記第１圧力補償弁２８はポペット弁３１を弁座３２に
押しつけてあり、そのポペット弁３１はチエツク弁３２
を構成するピストン３３の先端部に嵌合されて背圧室３
４を形成し、その背圧室３４は細孔３５で第１ポート１
６に連通し、かつピストン３３に形成した液孔３６で受
圧室３・７に連通会遮断され、ポペット３１は背圧室３
４と受圧室３７内の液圧で弁座３２に押しつけられてお
り、さらに受圧室３７は細孔３８で圧力導入ポート３９
に開口している。The first pressure compensation valve 28 has a poppet valve 31 pressed against a valve seat 32, and the poppet valve 31 is pressed against a check valve 32.
The back pressure chamber 3 is fitted into the tip of the piston 33 constituting the
4, the back pressure chamber 34 is connected to the first port 1 with a pore 35.
The poppet 31 communicates with the pressure receiving chambers 3 and 7 through a liquid hole 36 formed in the piston 33, and the poppet 31 communicates with the back pressure chamber 3.
4 and the pressure receiving chamber 37 are pressed against the valve seat 32 by the hydraulic pressure in the pressure receiving chamber 37, and the pressure receiving chamber 37 is further connected to the pressure introduction port 39 through the small hole 38.
It is open to

なお、第２圧力補償弁３０は第１圧力補償弁２８と同一
となっている。Note that the second pressure compensation valve 30 is the same as the first pressure compensation valve 28.

次に作動を説明する。Next, the operation will be explained.

第１受圧室２６．にパイロット圧油を供給してスプール
１２を第２図のように左方の第１位置に向けて移動する
と、第１ポンプポート１４と出口ポート１３が連通し、
第１ポート１６と第１作動ポート１８が連通し、第２作
動ポート１９が第２タンクポート２１に連通する。First pressure receiving chamber 26. When pilot pressure oil is supplied to the spool 12 and the spool 12 is moved toward the first position on the left as shown in FIG. 2, the first pump port 14 and the outlet port 13 are brought into communication.
The first port 16 and the first working port 18 communicate with each other, and the second working port 19 communicates with the second tank port 21 .

これにより、液圧ポンプ２２の吐出圧液は第１ポンプポ
ート１４−出口ポート１３→第１通路２７−第１圧力補
償弁２８−第１ポート１６→第１作動ポート１８と流れ
て液圧アクチュエータ２３の第１室２３１に供給され、
その第２室２３２内の液圧は第２作動ポート１９→第２
タンクポート２１よりタンク２４に流出する。As a result, the discharge pressure liquid of the hydraulic pump 22 flows from the first pump port 14 to the outlet port 13 to the first passage 27 to the first pressure compensating valve 28 to the first port 16 to the first operating port 18 to reach the hydraulic actuator. 23 is supplied to the first chamber 231,
The hydraulic pressure in the second chamber 232 is changed from the second operating port 19 to the second
It flows out from the tank port 21 to the tank 24.

この時、出口ポート１３より流出した液圧はポペット弁
３１の前面に作用してポペット弁３１を弁座３２より離
隔して第１ポート１６に流れるが、第１作動ポート１８
の圧力、つまり負荷圧が細孔３５、背圧室３４、液孔３
６、受圧室３７と流れ、圧力導入ポート３９に導かれる
。At this time, the hydraulic pressure flowing out from the outlet port 13 acts on the front surface of the poppet valve 31, separating the poppet valve 31 from the valve seat 32 and flowing to the first port 16.
The pressure, that is, the load pressure, is
6. It flows into the pressure receiving chamber 37 and is led to the pressure introduction port 39.

他方、この圧力導入ポート３９は複数の圧力補償付液圧
弁において相互に連通されるので、受圧室３７内の圧力
は最大圧、つまり最も負荷圧が高い液圧アクチュエータ
に見合う圧力となって、ポペット弁３１を弁座３２に押
しつける力はその圧力によって決定されるので、第１圧
力補償弁２８のセット圧は最も負荷圧が高い液圧アクチ
ュエータに見合うセット圧となる。On the other hand, since this pressure introduction port 39 is communicated with each other in a plurality of pressure compensated hydraulic valves, the pressure in the pressure receiving chamber 37 becomes the maximum pressure, that is, the pressure corresponding to the hydraulic actuator with the highest load pressure, and the poppet Since the force that presses the valve 31 against the valve seat 32 is determined by the pressure, the set pressure of the first pressure compensation valve 28 is a set pressure that corresponds to the hydraulic actuator with the highest load pressure.

前記圧力導入ポート３９は液圧ポンプ２２の容量制御部
材４０に連通し、液圧ポンプ２２の容量を、その吐出圧
Ｐ、が前記検出した最高圧Ｐ０よりも所定圧力、例えば
２０ｋｇ／ｃ−高くなるようにセットされ、メータイン
の圧力差ΔＰ１つまり第１ポンプポート１４と出口ポー
ト１３の連通面積による第１ポンプポート１４と出口ポ
ート１３の圧力差を例えば２０ｋｇ／ｃ−に一定にコン
トロールされる。The pressure introduction port 39 communicates with the capacity control member 40 of the hydraulic pump 22, and controls the capacity of the hydraulic pump 22 so that its discharge pressure P is a predetermined pressure, for example, 20 kg/c higher than the detected maximum pressure P0. The meter-in pressure difference ΔP1, that is, the pressure difference between the first pump port 14 and the outlet port 13 due to the communication area between the first pump port 14 and the outlet port 13, is controlled to be constant, for example, 20 kg/c-.

また、複数の圧力補償付液圧弁におけるメータインの圧
力差が同一であるから、複数の圧力補償付液圧弁を同時
操作した時に液圧ポンプ２２の吐出液圧を各液圧アクチ
ュエータに流量分配して供給して同時に作動できる。In addition, since the meter-in pressure difference in multiple pressure-compensated hydraulic valves is the same, when multiple pressure-compensated hydraulic valves are operated simultaneously, the discharge hydraulic pressure of the hydraulic pump 22 is distributed to each hydraulic actuator. can be supplied and operated at the same time.

また、第１作動ポート１８の圧力と第２作動ポート１９
の圧力を別々のチエツク弁３２．３２により検出するよ
うにしたので、その受圧室面積を異ならせたり、スプリ
ングセットを変化させることで第１圧力補償弁２８のセ
ット圧と第２圧力補償弁３０のセット圧を異ならせるこ
とができる。Moreover, the pressure of the first working port 18 and the second working port 19
Since the pressure of the first pressure compensating valve 28 and the second pressure compensating valve 30 are detected by separate check valves 32 and 32, the set pressure of the first pressure compensating valve 28 and that of the second pressure compensating valve 30 can be adjusted by changing the areas of the pressure receiving chambers or changing the spring set. The set pressure can be made different.

したがって、油圧アクチュエータ２３を負荷に抗して移
動する場合も戻し方向と移動する場合とに対応した圧力
にそれぞれセットできる。Therefore, even when the hydraulic actuator 23 is moved against a load, pressures can be set corresponding to the return direction and the case where the hydraulic actuator 23 is moved.

第３図は使用例を示し、液圧ポンプ２２の吐出側に２つ
の圧力補償付液圧弁を設けて２つの液圧アクチュエータ
、例えばパワーシ６ヨベルのブームシリンダ６０とアー
ムシリンダ６１に液圧を供給するようにしてあり、第１
・第２圧力補償弁２８．３０はメータリング部、つまり
出口ポート１３と第１番第２ポンプポート１４゜１５の
連通・遮断部６２の下流側に設けであるので、メータリ
ング部の開度を変更することで流量を制御でき、ブーム
シリンダ６０に多量の液圧を供給し、アームシリンダ６
１への液圧を少量することができる。FIG. 3 shows an example of use, in which two pressure-compensated hydraulic valves are provided on the discharge side of the hydraulic pump 22 to supply hydraulic pressure to two hydraulic actuators, such as the boom cylinder 60 and arm cylinder 61 of a power shovel. The first
- Since the second pressure compensating valve 28,30 is provided downstream of the metering section, that is, the communication/blocking section 62 between the outlet port 13 and the first and second pump ports 14 and 15, the opening degree of the metering section By changing the flow rate, a large amount of hydraulic pressure is supplied to the boom cylinder 60, and the arm cylinder 6
The hydraulic pressure to 1 can be reduced by a small amount.

したがって、従来のようにブームシリンダＢＯ用の高速
弁と低速弁を設けてブームシリンダ６０に多量の液圧を
供給する必要がなくなる。Therefore, it is no longer necessary to provide a high speed valve and a low speed valve for the boom cylinder BO to supply a large amount of hydraulic pressure to the boom cylinder 60 as in the conventional case.

〔発明の効果〕〔Effect of the invention〕

第１作動ポート１８の圧力と第２作動ポート１９の圧力
をそれぞれチエツク弁で検出し、その検出圧力に基づい
て第１・第２圧力補償弁２８゜３０のセット圧をそれぞ
れ決定して第１Φ第２作動ポート１８．１９のいずれか
一方への液圧をコントロールしているので、弁本体１０
に０字状の溝を形成する必要がなく、弁本体１０を容品
に製作、加工できると共に、第１作動ポート１８の圧力
と第２作動ポート１９の圧力とを異なる値にセットでき
、しかもスプール１２の中立時に第１・第２作動ポート
１８．１９の圧力がタンク側に洩れたりしない。The pressure in the first working port 18 and the pressure in the second working port 19 are detected by check valves, and based on the detected pressures, set pressures for the first and second pressure compensating valves 28 and 30 are respectively determined. Since the hydraulic pressure to either the second operating port 18 or 19 is controlled, the valve body 10
There is no need to form a 0-shaped groove in the valve body 10, and the valve body 10 can be manufactured and processed into a compact shape, and the pressure in the first operating port 18 and the pressure in the second operating port 19 can be set to different values. When the spool 12 is in the neutral state, the pressure in the first and second operating ports 18, 19 does not leak to the tank side.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は本発明の実施例を示す断面図、第２図は作動説
明図、第３図は使用例の説明図、第４図は従来例の断面
図である。 １０は弁本体、１２はスプール、 １４．１５は第１・第２ポンプポート、１８．１９は第
１・第２作動ポート、 ２８．３０は第１・第２圧力補償弁、 ３２はチエツク。FIG. 1 is a sectional view showing an embodiment of the present invention, FIG. 2 is an explanatory view of operation, FIG. 3 is an explanatory view of an example of use, and FIG. 4 is a sectional view of a conventional example. 10 is the valve body, 12 is the spool, 14.15 is the first and second pump ports, 18.19 is the first and second operating ports, 28.30 is the first and second pressure compensating valves, and 32 is the check.

Claims (1)

【特許請求の範囲】 　弁本体１０に、第１作動ポート１８を第１ポンプポー
ト１４と第１タンクポート２０にそれぞれ連通・遮断す
るとともに第２作動ポート１９を第２ポンプポート１５
と第２タンクポート２１にそれぞれ連通・遮断するスプ
ール１２を設け、前記第１ポンプポート１４より第１作
動ポート１８に流れる液体の圧力を設定する第１圧力補
償弁２８と、第１作動ポート１８の圧力を検出するチエ
ツク弁３２を設け、 前記第２ポンプポート１５より第２作動ポート１９に流
れる液体の圧力を設定する第２圧力補償弁３０と、第２
作動ポート１９の圧力を検出するチエツク弁３２を設け
、 前記各チエツク弁３２により検出した圧力における最高
圧で圧力補償弁のセツト圧を決定する構成としたことを
特徴とする圧力補償付液圧弁。[Claims] In the valve body 10, the first operating port 18 is connected to and disconnected from the first pump port 14 and the first tank port 20, respectively, and the second operating port 19 is connected to the second pump port 15.
A first pressure compensating valve 28 is provided with a spool 12 that communicates with and blocks the second tank port 21 and sets the pressure of the liquid flowing from the first pump port 14 to the first operating port 18, and the first operating port 18. a second pressure compensating valve 30 for setting the pressure of the liquid flowing from the second pump port 15 to the second operating port 19;
A hydraulic pressure valve with pressure compensation, characterized in that a check valve 32 is provided to detect the pressure of the operating port 19, and the set pressure of the pressure compensation valve is determined by the highest pressure among the pressures detected by each of the check valves 32.