JPH076501U - Pressure compensation valve - Google Patents

Pressure compensation valve

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Publication number
JPH076501U
JPH076501U JP3584193U JP3584193U JPH076501U JP H076501 U JPH076501 U JP H076501U JP 3584193 U JP3584193 U JP 3584193U JP 3584193 U JP3584193 U JP 3584193U JP H076501 U JPH076501 U JP H076501U
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JP
Japan
Prior art keywords
pressure
port
spool
check valve
load
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP3584193U
Other languages
Japanese (ja)
Inventor
光正 明石
年郎 高野
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Komatsu Ltd
Original Assignee
Komatsu Ltd
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Filing date
Publication date
Application filed by Komatsu Ltd filed Critical Komatsu Ltd
Priority to JP3584193U priority Critical patent/JPH076501U/en
Publication of JPH076501U publication Critical patent/JPH076501U/en
Pending legal-status Critical Current

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Abstract

(57)【要約】 【目的】 チェック弁部のスプールがスムーズに第１ポ
ートとポンプポートを遮断する位置に移動するようにす
る。 【構成】 チェック弁部２３と減圧弁部２４より成る圧
力補償弁２５において、そのチェック弁部２３の第１ポ
ート２９とポンプポート４４を連通・遮断するスプール
６０をスプリング１３１で第１ポート２９とポンプポー
ト４４を遮断する方向に押し、第１ポート２９よりポン
プポート４４に圧油が流れている時にその入口側圧力が
低下したらスプール６０がスプリング１３１で第１ポー
ト２９とポンプポート４４を遮断する位置に直ちに移動
するようにする。 (57) [Summary] [Purpose] The spool of the check valve unit should move smoothly to a position that shuts off the first port and pump port. [Structure] In a pressure compensating valve 25 composed of a check valve portion 23 and a pressure reducing valve portion 24, a spool 60 that connects and disconnects a first port 29 of the check valve portion 23 and a pump port 44 is connected to a first port 29 by a spring 131. When the pressure oil is flowing from the first port 29 to the pump port 44 when the pressure on the inlet side of the pump port 44 decreases, the spool 60 uses the spring 131 to shut off the first port 29 and the pump port 44. Try to move to position immediately.

Description

【考案の詳細な説明】[Detailed description of the device]

【０００１】[0001]

【産業上の利用分野】[Industrial applications]

本考案は、１つ又は複数の油圧ポンプの吐出圧油を複数のアクチュエータに供 給する圧油供給装置に用いる圧力補償弁に関する。 The present invention relates to a pressure compensating valve used in a pressure oil supply device that supplies the discharge pressure oil of one or a plurality of hydraulic pumps to a plurality of actuators.

【０００２】[0002]

【従来の技術】[Prior art]

かかる圧油供給装置としては図１に示すように、油圧ポンプ２０の吐出路２１ に複数の方向制御弁２２を設け、この各方向制御弁２２の入口側にチェック弁部 ２３と減圧弁部２４より成る圧力補償弁２５をそれぞれ設けたものが知られ、こ の方向制御弁２２と圧力補償弁２５は図２に示すように構成してある。 As shown in FIG. 1, such a pressure oil supply device is provided with a plurality of directional control valves 22 in a discharge passage 21 of a hydraulic pump 20, and a check valve portion 23 and a pressure reducing valve portion 24 are provided on the inlet side of each directional control valve 22. It is known that each pressure compensation valve 25 is provided, and the directional control valve 22 and the pressure compensation valve 25 are configured as shown in FIG.

【０００３】 すなわち、図２に示すように、弁ブロック３０は略直方体形状となり、この弁 ブロック３０の上部寄りにスプール孔３１が左右側面３２，３３に開口して形成 され、このスプール３１に開口した第１・第２アクチュエータポート３４，３５ が上面３６に開口して形成してあり、弁ブロック３０の下部寄りには左側面３２ に開口したチェック弁用孔３７と右側面３３に開口した減圧弁用孔３８が同心状 に形成され、前記チェック弁用孔３７に開口した第１ポート３９が前後面に開口 して形成され、前記減圧弁用孔３８に開口した第２、第３ポート４２，４３が前 後面に開口して形成してあり、複数の弁ブロック３０の前後面を突き合せて連結 すると各第１・第２・第３ポート３９，４２，４３が連通するようにしてある。That is, as shown in FIG. 2, the valve block 30 has a substantially rectangular parallelepiped shape, and a spool hole 31 is formed in the left and right side surfaces 32 and 33 near the upper portion of the valve block 30. The first and second actuator ports 34 and 35 are formed so as to open on the upper surface 36, and the check valve hole 37 opened on the left side surface 32 and the depressurization opening on the right side surface 33 are formed near the lower part of the valve block 30. The valve hole 38 is concentrically formed, the first port 39 opening to the check valve hole 37 is formed to open on the front and rear surfaces, and the second and third ports 42 opening to the pressure reducing valve hole 38. , 43 are formed to open at the front and rear surfaces, and when the front and rear surfaces of the plurality of valve blocks 30 are butted and connected to each other, the first, second, and third ports 39, 42, 43 communicate with each other. .

【０００４】 前記弁ブロック３０にはスプール孔３１に開口したポンプポート４４、第１・ 第２負荷圧検出ポート４５，４６、前記第１・第２アクチュエータポート３４， ３５、第１、第２タンクポート４７，４８が形成され、そのスプール孔３１に嵌 挿した主スプール４９には第１・第２小径部５０，５１と連通用溝５２が形成し てあり、主スプール４９には第１・第２負荷圧検出ポート４５，４６を常時連通 する第１油路５３及び第２負荷圧検出ポート４６と第２タンクポート４８を連通 ・遮断する第２油路５４が形成され、スプール４９はスプリングで各ポートを遮 断し、第２油路５４で第２負荷圧検出ポート４６と第２タンクポート４８を連通 する中立位置に保持され、スプール４９を右方に摺動すると第２小径部５１で第 ２アクチュエータポート３５を第２タンクポート４８に連通し、連通用溝５２で ポンプポート４４が第２負荷圧検出ポート４６に連通し、第１小径部５０で第１ アクチュエータポート３４が第１負荷圧検出ポート４５に連通し、かつ第２負荷 圧検出ポート４６と第２タンクポート４８が遮断する第１圧油供給位置となり、 スプール４９を左方に摺動すると第１小径部５０で第１アクチュエータポート３ ４を第１タンクポート４７に連通し、連通用溝５２でポンプポート４４が第１負 荷圧検出ポート４５に連通し、第２小径部５１で第２アクチュエータポート３５ が第２負荷圧検出ポート４６に連通し、かつ第２負荷圧検出ポート４６と第２タ ンクポート４８が遮断する第２圧油供給位置となって方向制御弁２２を構成して いる。The valve block 30 has a pump port 44 opened to the spool hole 31, first and second load pressure detection ports 45 and 46, first and second actuator ports 34 and 35, first and second tanks. Ports 47 and 48 are formed, the main spool 49 fitted in the spool hole 31 has first and second small diameter portions 50 and 51, and a communication groove 52. The main spool 49 has the first and second small diameter portions 50 and 51. A first oil passage 53 that constantly connects the second load pressure detection ports 45 and 46 and a second oil passage 54 that connects and disconnects the second load pressure detection port 46 and the second tank port 48 are formed, and the spool 49 is a spring. Each port is cut off with and the second oil passage 54 holds the neutral position where the second load pressure detection port 46 and the second tank port 48 communicate with each other. When the spool 49 slides to the right, the second small diameter portion 51 And second The actuator port 35 communicates with the second tank port 48, the pump groove 44 communicates with the second load pressure detection port 46 through the communication groove 52, and the first actuator port 34 detects the first load pressure through the first small diameter portion 50. It is in the first pressure oil supply position that communicates with the port 45, and the second load pressure detection port 46 and the second tank port 48 are shut off. When the spool 49 slides to the left, the first small diameter portion 50 causes the first actuator port to move. 34 is communicated with the first tank port 47, the pump groove 44 is communicated with the first load pressure detection port 45 through the communication groove 52, and the second actuator port 35 is detected with the second load pressure through the second small diameter portion 51. The directional control valve 22 is formed at a second pressure oil supply position that communicates with the port 46 and that the second load pressure detection port 46 and the second tank port 48 are shut off from each other.

【０００５】 前記チェック弁用孔３７は油路５６でポンプポート４４に開口し、そのチェッ ク弁用孔３７には前記第１ポート３９とポンプポート４４を連通遮断する弁６０ が嵌挿され、その弁６０はプラグ６１に設けたストッパ杆６２で図示位置より左 方に摺動しないように規制されて遮断位置に保持されてチェック弁部２３を構成 している。 前記減圧弁用孔３８は第４ポート５７と油路５８で第２負荷圧検出ポート４６ に連通し、この減圧弁用孔３８にはスプール６４が嵌挿されて第１圧力室６５と 第２圧力室６６を形成し、第１圧力室６５は第４ポート５７に連通し、第２圧力 室６６は第３ポート４３に連通し、前記スプール６４の盲穴６７に挿入したフリ ーピストン６８と盲穴６７底部との間にばね６９が設けられてフリーピストン６ ８はプラグ７０に当接し、かつスプール６４に一体的に設けた押杆７１が透孔７ ２より突出して前記弁６０をストッパ杆６２に当接しており、前記スプール６４ には第２ポート４２を盲穴６７に連通する細孔７３が形成されて減圧弁部２４を 構成し、この減圧弁部２４と前記チェック弁部２３とで圧力補償弁２５を構成し ている。The check valve hole 37 is opened to the pump port 44 through the oil passage 56, and the check valve hole 37 is fitted with a valve 60 that shuts off the communication between the first port 39 and the pump port 44. The valve 60 is restricted by a stopper rod 62 provided on a plug 61 so as not to slide to the left from the position shown in the figure, and is held at a shutoff position to form a check valve portion 23. The pressure reducing valve hole 38 communicates with the second load pressure detecting port 46 through the fourth port 57 and the oil passage 58, and the spool 64 is fitted in the pressure reducing valve hole 38 to connect the first pressure chamber 65 and the second pressure chamber 65. A pressure chamber 66 is formed, the first pressure chamber 65 communicates with the fourth port 57, the second pressure chamber 66 communicates with the third port 43, and the free piston 68 inserted in the blind hole 67 of the spool 64 and a blind piston 68 are connected to each other. A spring 69 is provided between the free piston 68 and the bottom of the hole 67 so that the free piston 68 abuts on the plug 70, and a push rod 71 integrally provided on the spool 64 projects from the through hole 72 so that the valve 60 is stopped by the stopper rod. 62, and a fine hole 73 is formed in the spool 64 to connect the second port 42 to the blind hole 67 to form the pressure reducing valve portion 24. The pressure reducing valve portion 24 and the check valve portion 23 are connected to each other. Pressure compensating valve 25.

【０００６】 そして、図１に示すように油圧ポンプ２０の吐出路２１を第１ポート３９、第 ２ポート４２に連通し、第３ポート４３に負荷圧検出路８２を接続し、第１・第 ２アクチュエータポート３４，３５にアクチュエータ８８が接続してある。 図２において、８３は油圧ポンプ８０の吐出流量を制御する斜板、８４はサー ボシリンダ、８５はポンプ調整用方向制御弁である。As shown in FIG. 1, the discharge passage 21 of the hydraulic pump 20 is communicated with the first port 39 and the second port 42, and the load pressure detection passage 82 is connected to the third port 43. An actuator 88 is connected to the two actuator ports 34 and 35. In FIG. 2, 83 is a swash plate that controls the discharge flow rate of the hydraulic pump 80, 84 is a servo cylinder, and 85 is a directional control valve for pump adjustment.

【０００７】 次に作動を図１に基づいて説明する。 方向制御弁２２が中立位置Ａのとき。 油圧ポンプ２０によってタンク８６から吸上げられた油は、吐出路２１を通っ てチェック弁部２３の開く方向の圧力室ａに案内される。この時、減圧弁部２４ の圧力室６５，６６は、ともにタンク８６に通じているので、この圧力室６５， ６６の圧力はともにゼロで、よって減圧弁部２４は、弱いばね６９によって押さ れ杆体７１がチェック弁部２３に当接しているだけである。 一方、ポンプ吐出圧は、ポンプ調整用方向制御弁８５のばね８７によって負荷 圧検出路８２の圧力との差圧がある一定に保たれる。いま、この差圧を２０ｋｇ ／ｃｍ2 とすると負荷圧検出路８２の圧力はゼロなので、ポンプ吐出圧は２０ｋ ｇ／ｃｍ2 まで上昇し、同時にチェック弁部２３の圧力室ａにポンプ吐出圧が流 入して方向制御弁２２の入口圧（チェック弁部６３の出口圧）がポンプ吐出圧と 等しくなるまでストロークし、等しくなれば、弱いばね６９によってレシートす る。 減圧弁部２４は、ストロークエンド時のみ、ポンプ吐出路８１と圧力室６６を 連通させる一方、チェック弁部２３は、ストロークエンドに達する前に、ポンプ 吐出路８１と出口側を連通させるので、方向制御弁２２が中立位置Ａのときは、 ポンプ吐出路２１と圧力室６６が連通することはなく、圧力室６５の圧力はゼロ のままである。Next, the operation will be described with reference to FIG. When the directional control valve 22 is in the neutral position A. The oil sucked up from the tank 86 by the hydraulic pump 20 is guided through the discharge passage 21 to the pressure chamber a in the opening direction of the check valve portion 23. At this time, since the pressure chambers 65 and 66 of the pressure reducing valve portion 24 both communicate with the tank 86, the pressures of the pressure chambers 65 and 66 are both zero, so the pressure reducing valve portion 24 is pressed by the weak spring 69. The rod 71 is only in contact with the check valve portion 23. On the other hand, the pump discharge pressure is kept constant by the spring 87 of the pump adjusting directional control valve 85, which is a differential pressure from the pressure of the load pressure detecting path 82. Now, assuming that this differential pressure is 20 kg / cm 2 , the pressure in the load pressure detection path 82 is zero, so the pump discharge pressure rises to 20 kg / cm 2, and at the same time, the pump discharge pressure enters the pressure chamber a of the check valve section 23. After flowing in, the stroke is made until the inlet pressure of the directional control valve 22 (the outlet pressure of the check valve portion 63) becomes equal to the pump discharge pressure, and when they become equal, the weak spring 69 makes a receipt. The pressure reducing valve portion 24 communicates the pump discharge passage 81 with the pressure chamber 66 only at the end of the stroke, while the check valve portion 23 communicates the pump discharge passage 81 with the outlet side before reaching the stroke end. When the control valve 22 is in the neutral position A, the pump discharge passage 21 and the pressure chamber 66 do not communicate with each other, and the pressure in the pressure chamber 65 remains zero.

【０００８】 方向制御弁２２のいずれか一方のみ第１圧油供給位置Ｂにストロークさせる とき。 いま、左側の方向制御弁２２を第１圧油供給位置Ｂにストロークさせ、右側の 方向制御弁２２は、中立位置Ａとする。 方向制御弁２２をストロークさせポンプポート４４と第１アクチュエータポー ト３４を接続させ、同時に、第２アクチュエータ３５と第２タンクポート４８を 接続させる。この時第１アクチュエータポート３４とアクチュエータ８８を接続 する導管８９内の圧力（負荷圧）がポンプ吐出圧（２０ｋｇ／ｃｍ2 ）より大き いときはチェック弁部２３が圧力室ｂの圧力でレシートするため、アクチュエー タ８８の自然降下を防止することができる。 アクチュエータ８８の導管８９の圧力、すなわち負荷圧が第１油路５３、通路 ５８より減圧弁部２４の一方の圧力室６５に導かれる。他方の圧力室６６の圧力 はゼロであるため、減圧弁部２４は、チェック弁部２３から解離する方向にスト ロークエンドまでストロークし、減圧弁部２４の絞りを介して、ポンプ吐出路２ １と負荷圧検出路８２が連通する。前記導管８９内の圧力（負荷圧）がポンプ吐 出圧（＝２０ｋｇ／ｃｍ2 ）より大きいときは、チェック弁部２３の圧力室ｂの 圧力で閉じ、その圧力が、減圧弁部２４の一方の圧力室６５に導かれるため、他 方の圧力室６６とポンプ吐出路２１が連通しても、減圧弁部２４はストロークし たままである。一方、導管４１内の圧力（負荷圧）がポンプ吐出圧（＝２０ｋｇ ／ｃｍ2 ）より小さいときは、その負荷圧が減圧弁部２４の一方の圧力室６５に 導かれ、減圧弁部２４が一方の圧力室６５の圧力でストロークするが、他方の圧 力室６６の圧力が一方の圧力室６５の圧力（すなわち負荷圧）まで上昇すると、 弱いばね６９によって閉じチェック弁部２３に当接する。 いずれの場合でも、減圧弁部２４は、一方の圧力室６５内の圧力と他方の圧力 室６６内の圧力が等しくなるまで、ポンプ吐出路２１と圧力室６６を連通させ、 両圧力室６５，６６内の圧力が等しくなれば弱いばね６９によって閉じチェック 弁部２３に当接する。結果として負荷圧検出路８２内の圧力は、負荷圧と等しく なり、ポンプ吐出圧は、ポンプ調整用方向制御弁８５によって、ある差圧（ここ では２０ｋｇ／ｃｍ2 ）分だけ、負荷圧検出路８２内の圧力より高い圧力に制御 される。このポンプ吐出圧は、チェック弁部２３を介して、ポンプポート４４に 導かれているので、すなわち、方向制御弁２２の入口圧と出口圧（＝負荷圧）の 間には、差圧（＝２０ｋｇ／ｃｍ2 ）が保たれることになる。よって、方向制御 弁２２のストロークに伴なう入口側と出口側の間の絞りの開口面積の変化によっ てのみ、アクチュエータ８８へ供給される流量が制御される。 方向制御弁２２をストロークさせる際、アクチュエータ８８の導管８９あるい は９０と負荷圧導入用の第２油路５３が接続され、一方、第２油路５３は、減圧 弁部２４の一方の圧力室６５と接続されているが、減圧弁部２４において負荷圧 は、パイロット圧力（減圧弁部のセット圧力）としてのみ使われるので、その圧 力がぬけることはなく、すなわち、方向制御弁２２をストロークさせた際、負荷 圧がぬけることによるアクチュエータ８８の自然降下はない。When only one of the directional control valves 22 is stroked to the first pressure oil supply position B. Now, the left directional control valve 22 is stroked to the first pressure oil supply position B, and the right directional control valve 22 is set to the neutral position A. The directional control valve 22 is stroked to connect the pump port 44 and the first actuator port 34, and at the same time, connect the second actuator 35 and the second tank port 48. At this time, when the pressure (load pressure) in the conduit 89 connecting the first actuator port 34 and the actuator 88 is higher than the pump discharge pressure (20 kg / cm 2 ), the check valve portion 23 receives the pressure in the pressure chamber b. Therefore, it is possible to prevent the actuator 88 from naturally descending. The pressure of the conduit 89 of the actuator 88, that is, the load pressure, is introduced into the pressure chamber 65 of the pressure reducing valve portion 24 from the first oil passage 53 and the passage 58. Since the pressure in the other pressure chamber 66 is zero, the pressure reducing valve unit 24 strokes in the direction of disengagement from the check valve unit 23 to the stroke end, and through the throttle of the pressure reducing valve unit 24, the pump discharge passage 21 And the load pressure detection path 82 communicate with each other. When the pressure (load pressure) in the conduit 89 is higher than the pump discharge pressure (= 20 kg / cm 2 ), the pressure is closed by the pressure in the pressure chamber b of the check valve portion 23, and the pressure is reduced to one of the pressure reducing valve portions 24. Since the pressure reducing valve portion 24 is guided to the pressure chamber 65, the pressure reducing valve portion 24 remains in a stroke even when the other pressure chamber 66 communicates with the pump discharge passage 21. On the other hand, when the pressure (load pressure) in the conduit 41 is lower than the pump discharge pressure (= 20 kg / cm 2 ), the load pressure is guided to one pressure chamber 65 of the pressure reducing valve portion 24, and the pressure reducing valve portion 24 is Although the stroke is made by the pressure of one pressure chamber 65, when the pressure of the other pressure chamber 66 rises to the pressure of one pressure chamber 65 (that is, the load pressure), the weak spring 69 closes and abuts against the check valve portion 23. In any case, the pressure reducing valve section 24 makes the pump discharge passage 21 and the pressure chamber 66 communicate with each other until the pressure inside the one pressure chamber 65 and the pressure inside the other pressure chamber 66 become equal to each other. If the pressures in 66 become equal, a weak spring 69 makes contact with the closing check valve portion 23. As a result, the pressure in the load pressure detection path 82 becomes equal to the load pressure, and the pump discharge pressure is adjusted by the pump adjustment directional control valve 85 by a certain differential pressure (here, 20 kg / cm 2 ). The pressure is controlled to be higher than the pressure in 82. This pump discharge pressure is guided to the pump port 44 via the check valve portion 23, that is, between the inlet pressure and the outlet pressure (= load pressure) of the directional control valve 22, a differential pressure (= 20 kg / cm 2 ) will be maintained. Therefore, the flow rate supplied to the actuator 88 is controlled only by the change in the opening area of the throttle between the inlet side and the outlet side due to the stroke of the directional control valve 22. When the directional control valve 22 is stroked, the conduit 89 or 90 of the actuator 88 and the second oil passage 53 for introducing the load pressure are connected, while the second oil passage 53 is connected to the pressure of one of the pressure reducing valve portions 24. Although it is connected to the chamber 65, the load pressure in the pressure reducing valve section 24 is used only as pilot pressure (set pressure of the pressure reducing valve section), so the pressure is not lost, that is, the directional control valve 22 is When the stroke is made, there is no spontaneous lowering of the actuator 88 due to the release of the load pressure.

【０００９】 前記負荷圧検出路８２はもう一方の方向制御弁２２に配設されている圧力補償 弁２５の減圧弁部２４の他方の圧力室６６にも接続されているが、減圧弁部２４ の一方の圧力室６５は、方向制御弁２２の中立位置Ａによってタンク８６と接続 しているため、負荷圧導入用の第１油路５３内の圧力はゼロで、よって圧力室６ ６内の圧力によって減圧弁部２４は、チェック弁部２３を閉じる方向に付勢する 。一方、チェック弁部２４を開く方向の圧力室ａには、ポンプ吐出路８１よりポ ンプ吐出圧が導かれるため、全体として、ポンプ吐出圧と負荷圧検出路８２内の 圧力の差圧分（＝２０ｋｇ／ｃｍ2 ）によってチェック弁部２３及び減圧弁部２ ４をチェック弁部２３の開く方向にストロークさせるが、わずかにストロークし ポンプポート４４の圧力がその差圧（＝２０ｋｇ／ｃｍ2 ）になれば、弱いばね ６９によってレシートし、結果として、ストロークエンドまで減圧弁部２４がス トロークすることはなく、方向制御弁２２側の油圧制御には、何ら影響すること はない。The load pressure detection path 82 is also connected to the other pressure chamber 66 of the pressure reducing valve portion 24 of the pressure compensating valve 25 arranged in the other directional control valve 22, but the pressure reducing valve portion 24 Since one of the pressure chambers 65 is connected to the tank 86 by the neutral position A of the directional control valve 22, the pressure in the first oil passage 53 for introducing the load pressure is zero, and therefore the pressure chamber 66 is The pressure reducing valve 24 urges the check valve 23 in the closing direction. On the other hand, since the pump discharge pressure is introduced from the pump discharge passage 81 to the pressure chamber a in the direction of opening the check valve portion 24, as a whole, the pressure difference between the pump discharge pressure and the pressure in the load pressure detection passage 82 ( = 20 kg / cm 2 ), the check valve portion 23 and the pressure reducing valve portion 24 are stroked in the opening direction of the check valve portion 23, but a slight stroke occurs, and the pressure of the pump port 44 is the differential pressure (= 20 kg / cm 2 ). In this case, the weak spring 69 causes a receipt, and as a result, the pressure reducing valve portion 24 does not strike until the stroke end, and the hydraulic control on the directional control valve 22 side is not affected at all.

【００１０】 方向制御弁２２のいずれも第１圧油供給位置Ｂにストロークさせるとき。 −各アクチュエータ８８に必要とされる流量の合計が油圧ポンプ２０の最 大吐出流量位置のとき。 いま、方向制御弁２２をともに第１圧油供給位置Ｂにストロークさせ、各ポン プポート４４と各導管８９と各負荷圧導用の第１油路５３をそれぞれ接続させた とする。 一方の減圧弁部２４は、圧力室６６内の圧力が一方の圧力室６５内の圧力に等 しくなるまで、また他方の減圧弁部２４は、圧力室６６内の圧力が、一方の圧力 室６５内の圧力に等しくなるまで、それぞれストロークエンドまでストロークし たままである。いま、二つのアクチュエータ８８，８８の負荷圧のうち、左側の アクチュエータ８８の負荷圧がより大きいとする。仮に、左側アクチュエータ２ ６の負荷圧を１００（ｋｇ／ｃｍ2 ）、右側のアクチュエータ２７の負荷圧を１ ０（ｋｇ／ｃｍ2 ）とする。負荷圧検出路８２は、絞り９１を介してタンク８６ と接続されているので、方向制御弁ストローク前は負荷圧検出路８２内の圧力は ゼロである。よって、各減圧弁部２４は負荷圧検出用の第１油路５３内の圧力に よってもストロークし、ポンプ吐出圧が圧力検出導管３４内の圧力と連通させる 。 負荷圧検出路８２内の圧力が低圧側である右側のアクチュエータ８８の導管９ ０内の圧力（１０ｋｇ／ｃｍ2 ）まで上昇すると、まず、右方の圧力補償弁２５ の減圧弁部２４が閉じる。左方の圧力補償弁２５の減圧弁部２４はストロークし たままであり、負荷圧検出路８２内の圧力はポンプ吐出圧（２０ｋｇ／ｃｍ2 ） と等しくなるまで上昇する。このとき高圧側である左側のアクチュエータ８８の 方向制御弁５５のポンプポート４４の圧力は１００（ｋｇ／ｃｍ2 ）であり、圧 力補償弁２５のチェック弁部２３は閉じていて、減圧弁部２４とは解離している 。一方圧力補償弁２５の減圧弁部２４は、二つの圧力室６５と６６内の圧力の差 （２０−１０＝１０ｋｇ／ｃｍ2 ）でチェック弁部２３を閉じる方向に付勢する 。一方、チェック弁部２３の開く方向の圧力室ａ内の圧力（ポンプ吐出圧）は２ ０（ｋｇ／ｃｍ2 ）であるため、結果として方向制御弁２２のポンプポート４４ の圧力が１０（ｋｇ／ｃｍ2 ）になるまでチェック弁部２３が開いた後、弱いば ね６９によってレシートする。 ポンプ調整用方向制御弁８５によって、ある差圧（２０ｋｇ／ｃｍ2 ）分だけ 、負荷圧検出路８２内の圧力（２０ｋｇ／ｃｍ2 ）より高い圧力にポンプ吐出圧 が制御される（４０ｋｇ／ｃｍ2 ）。このときも高圧側の圧力補償弁２５のチェ ック弁部２３は閉じたままで減圧弁部２４はストロークしたままで負荷圧検出路 ８２内の圧力は４０（ｋｇ／ｃｍ2 ）となり、一方、低圧側の圧力補償弁２５の 減圧弁部２４は、負荷圧検出路８２と負荷圧導入用の第１油路５３内の圧力差（ ＝３０ｋｇ／ｃｍ2 ）でチェック弁部２３を閉じる方向に付勢し、結果として方 向制御弁２２のポンプポート４４の圧力は１０ｋｇ／ｃｍ2 のままである。 このようにして、負荷圧検出路８２内の圧力とポンプ吐出圧が上昇し続け、や がてポンプ吐出圧が高圧側のアクチュエータ８８の負荷圧（１００ｋｇ／ｃｍ2 ）と等しくなると、高圧側の圧力補償弁２５の減圧弁部２３の二つの圧力室６５ と６６内の圧力はともに１００ｋｇ／ｃｍ2 となり、弱いばね６９によって、閉 じチェック弁部２３に当接する。このとき低圧側の圧力補償弁２５の減圧弁部２ ４は負荷圧検出路８２と負荷圧導入用の第１油路５３内の圧力差（１００−１０ ＝９０ｋｇ／ｃｍ2 ）でチェック弁部２３を閉じる方向に付勢し、結果として低 圧側の方向制御弁２２のポンプポート４４の圧力は１０ｋｇ／ｃｍ2 のままであ る。 再び、ポンプ調整用方向制御弁８５によって、ポンプ吐出圧が１２０（ｋｇ／ ｃｍ2 ）に制御される。 このとき高圧側の圧力補償弁２５の減圧弁部２３は、弱いばね６９によってチ ェック弁部２３に当接しているだけであり、チェック弁部２３の二つの圧力室ａ とｂの圧力差によって、ここで始めてチェック弁部２３が開き、ポンプ吐出圧（ １２０ｋｇ／ｃｍ2 ）が方向制御弁２２のポンプポート４４に導かれる。一方、 低圧側の圧力補償弁２５の減圧弁部２４は負荷圧検出路８２と負荷圧導入用の第 １油路５３内の圧力差（＝９０ｋｇ／ｃｍ2 ）分でチェック弁部２３を閉じる方 向に付勢し続けるが、チェック弁部２３の開く方向の圧力室ａ内の圧力が１２０ （ｋｇ／ｃｍ2 ）になったので方向制御弁２２の入口ポート４４の圧力が３０（ ｋｇ／ｃｍ2 ）（１２０−９０）となる状態で、チェック弁部２３及び減圧弁部 ２４が圧力バランスする。すなわち、チェック弁部２３及び減圧弁部２４はわず かにストロークし、チェック弁部２３において、１２０ｋｇ／ｃｍ2 から３０ｋ ｇ／ｃｍ2 になるように絞っている状態となる。 ここで初めて、この油圧制御系はつり合い、高圧側の方向制御弁２２のポンプ ポート４４の圧力が１２０ｋｇ／ｃｍ2 、低圧側の方向制御弁２２のポンプポー ト４４の圧力が３０ｋｇ／ｃｍ2 となり、すなわち、二つの方向制御弁２２，２ ２の入口圧と出口圧（負荷圧）の差は、ともに２０ｋｇ／ｃｍ2 に保たれること により、二つの方向制御弁２２，２２はともに、ストローク分だけで、アクチュ エータ８８，８８に供給する流量を制御することができるようになる。When any of the directional control valves 22 is stroked to the first pressure oil supply position B. -When the total flow rate required for each actuator 88 is at the maximum discharge flow rate position of the hydraulic pump 20. Now, it is assumed that the directional control valves 22 are both stroked to the first pressure oil supply position B and the respective pump ports 44, the respective conduits 89, and the respective first oil passages 53 for introducing the load pressure are connected. One of the pressure reducing valve portions 24 has the pressure in the pressure chamber 66 equal to the pressure in the one pressure chamber 65, and the other pressure reducing valve portion 24 has the pressure in the pressure chamber 66 equal to that of the one pressure chamber 65. It continues to stroke to the end of each stroke until it becomes equal to the pressure in 65. Now, assume that the load pressure of the left actuator 88 is larger than the load pressure of the two actuators 88, 88. It is assumed that the load pressure of the left actuator 26 is 100 (kg / cm 2 ) and the load pressure of the right actuator 27 is 10 (kg / cm 2 ). Since the load pressure detection path 82 is connected to the tank 86 via the throttle 91, the pressure in the load pressure detection path 82 is zero before the stroke of the directional control valve. Therefore, each pressure reducing valve section 24 also strokes due to the pressure in the first oil passage 53 for detecting the load pressure, and the pump discharge pressure communicates with the pressure in the pressure detection conduit 34. When the pressure in the load pressure detection path 82 rises to the pressure (10 kg / cm 2 ) in the conduit 90 of the actuator 88 on the right side, which is the low pressure side, first, the pressure reducing valve portion 24 of the pressure compensating valve 25 on the right side closes. . The pressure reducing valve portion 24 of the pressure compensating valve 25 on the left side is still in a stroke, and the pressure in the load pressure detecting path 82 rises until it becomes equal to the pump discharge pressure (20 kg / cm 2 ). At this time, the pressure of the pump port 44 of the directional control valve 55 of the left-side actuator 88 on the high pressure side is 100 (kg / cm 2 ), the check valve portion 23 of the pressure compensation valve 25 is closed, and the pressure reducing valve portion is closed. It is dissociated from 24. On the other hand, the pressure reducing valve portion 24 of the pressure compensating valve 25 urges the check valve portion 23 in the closing direction by the difference in pressure (20-10 = 10 kg / cm 2 ) in the two pressure chambers 65 and 66. On the other hand, the pressure in the pressure chamber a in the opening direction of the check valve portion 23 (pump discharge pressure) is 20 (kg / cm 2 ), and as a result, the pressure of the pump port 44 of the directional control valve 22 is 10 (kg / Cm 2 ), the check valve portion 23 is opened, and then a receipt is made with a weak bar 69. The pump adjusting directional control valve 85 controls the pump discharge pressure to a pressure higher than the pressure (20 kg / cm 2 ) in the load pressure detection path 82 by a certain pressure difference (20 kg / cm 2 ) (40 kg / cm 2 ). 2 ). Also at this time, the pressure in the load pressure detection path 82 becomes 40 (kg / cm 2 ) while the check valve portion 23 of the high-pressure side pressure compensating valve 25 remains closed and the pressure reducing valve portion 24 remains stroked. The pressure reducing valve portion 24 of the pressure compensating valve 25 on the low pressure side is closed in the direction in which the check valve portion 23 is closed due to the pressure difference (= 30 kg / cm 2 ) in the load pressure detecting passage 82 and the first oil passage 53 for introducing the load pressure. Energized, resulting in the pressure at pump port 44 of directional control valve 22 remaining at 10 kg / cm 2 . In this way, the pressure in the load pressure detection path 82 and the pump discharge pressure continue to rise, and when the pump discharge pressure eventually becomes equal to the load pressure (100 kg / cm 2 ) of the high pressure side actuator 88, the high pressure side The pressures in the two pressure chambers 65 and 66 of the pressure reducing valve section 23 of the pressure compensating valve 25 are both 100 kg / cm 2 , and the weak spring 69 makes contact with the closing check valve section 23. At this time, the pressure reducing valve portion 24 of the pressure compensating valve 25 on the low pressure side has a check valve portion due to a pressure difference (100-10 = 90 kg / cm 2 ) in the load pressure detecting passage 82 and the first oil passage 53 for introducing the load pressure. 23 is urged in the closing direction, and as a result, the pressure of the pump port 44 of the directional control valve 22 on the low pressure side remains 10 kg / cm 2 . Again, the pump adjusting directional control valve 85 controls the pump discharge pressure to 120 (kg / cm 2 ). At this time, the pressure reducing valve portion 23 of the pressure compensating valve 25 on the high pressure side is only in contact with the check valve portion 23 by the weak spring 69, and due to the pressure difference between the two pressure chambers a and b of the check valve portion 23. For the first time, the check valve portion 23 is opened and the pump discharge pressure (120 kg / cm 2 ) is introduced to the pump port 44 of the directional control valve 22. On the other hand, the pressure reducing valve portion 24 of the pressure compensating valve 25 on the low pressure side closes the check valve portion 23 by the pressure difference (= 90 kg / cm 2 ) in the load pressure detecting passage 82 and the first oil passage 53 for introducing the load pressure. Although the pressure continues to be urged in the direction, the pressure in the pressure chamber a in the opening direction of the check valve portion 23 becomes 120 (kg / cm 2 ), so the pressure of the inlet port 44 of the directional control valve 22 becomes 30 (kg / kg / cm 2 ) (120-90), the check valve portion 23 and the pressure reducing valve portion 24 balance the pressure. That is, the check valve 23 and the pressure reducing valve section 24 and Hawazu crab stroke, the check valve unit 23, a state in which focus on consist 120 kg / cm 2 to 30k g / cm 2. For the first time, the hydraulic control system is balanced so that the pressure of the pump port 44 of the directional control valve 22 on the high pressure side is 120 kg / cm 2 and the pressure of the pump port 44 of the directional control valve 22 on the low pressure side is 30 kg / cm 2 . That is, since the difference between the inlet pressure and the outlet pressure (load pressure) of the two directional control valves 22 and 22 is maintained at 20 kg / cm 2 , both of the two directional control valves 22 and 22 are equivalent to the stroke amount. Only by doing so, it becomes possible to control the flow rate supplied to the actuators 88, 88.

【００１１】 −各アクチュエータ８８，８８に必要とされる流量は合計が油圧ポンプ８ ０の最大吐出流量以上のとき。 いま、アクチュエータ８８，８８の負荷圧および必要流量を左側のアクチュエ ータ８８が１００ｋｇ／ｃｍ2 、５０１／ｍｉｎ、右側のアクチュエータ８８が １０ｋｇ／ｃｍ2 、５０１／ｍｉｎとする。油圧ポンプ８０の最大吐出流量が１ ００１／ｍｉｎ以上のときは、前述の通り、方向制御弁２２，２２の入口圧と出 口圧の差が一定に保たれる（＝２０ｋｇ／ｃｍ2 ）ため、ストロークによって流 量制御ができ、５０１／ｍｉｎずつ流量分配することはできる。 次に、油圧ポンプ８０の滞在吐出量が７０１／ｍｉｎになったとする。二つの 方向制御弁２２，２２の入口圧は前述の通り１２０ｋｇ／ｃｍ2 、３０ｋｇ／ｃ ｍ2 であるので、高圧側の方向制御弁２２への流量が５０１／ｍｉｎから２０１ ／ｍｉｎに減る。低圧側の方向制御弁２２への流量は、５０１／ｍｉｎのままで ある。二つの方向制御弁２２，２２のストローク（開口面積）を変えないとする と、高圧側の方向制御弁２２の入口圧と出口圧の差圧が流量が減った分、２０ｋ ｇ／ｃｍ2 から下がる。いま、差圧が１４ｋｇ／ｃｍ2 、すなわち、入口圧が、 １２０ｋｇ／ｃｍ2 から１１４（１００＋１４）ｋｇ／ｃｍ2 に下がったとする 。この時圧力補償弁２５の減圧弁部２４の二つの圧力室６５，６６の圧力は、と もに１００ｋｇ／ｃｍ2 のままであるから、減圧弁部２４は弱いばね６９によっ てチェック弁部２３に当接しているだけであり、チェック弁部２３の閉じる方向 の圧力室ｂ内の圧力が１２０ｋｇ／ｃｍ2 から１１４ｋｇ／ｃｍ2 に減少すれば 、チェック弁部２３が開いたまま（ストロークエンド）で、チェック弁部２３の 開く方向の圧力室ａ内の圧力、すなわち、ポンプ吐出圧が１２０ｋｇ／ｃｍ2 か ら１１４ｋｇ／ｃｍ2 に減少する。この時（ポンプ吐出流量不足時）にはポンプ 吐出圧はポンプ調整用方向制御弁８５の制御によらなくなる。 一方、低圧側の圧力補償弁２５の減圧弁部２４の二つの圧力室６５と６６は、 １００ｋｇ／ｃｍ2 、１０ｋｇ／ｃｍ2 のままで、その差圧９０ｋｇ／ｃｍ2 で チェック弁部６３の閉じる方向に付勢し続ける。一方、チェック弁部２３の開く 方向の圧力室ａ内の圧力、すなわちポンプ吐出圧が１１４ｋｇ／ｃｍ2 に減少し たので、チェック弁部２３の閉じる方向の圧力室ｂ内の圧力が３０ｋｇ／ｃｍ2 から２４ｋｇ／ｃｍ2 に減少した状態でチェック弁部２３及び減圧弁部２４が圧 力バランスする。よって、低圧側の方向制御弁２２の入口圧と出口圧の差圧は２ ０ｋｇ／ｃｍ2 から１４ｋｇ／ｃｍ2 （２４−１０）に減少する。方向制御弁２ ２のこの差圧の減少により低圧側のアクチュエータ８８への供給流量は５０１／ ｍｉｎから減少し、その分高圧側のアクチュエータ８８への供給流量が２０１／ ｍｉｎから増える。 すなわち、方向制御弁２２および２２の入口圧と出口圧の差圧が等しく、かつ 、二つのアクチュエータ８８，８８への供給量がともに３５１／ｍｉｎずつに分 配される状態で、この油圧制御系がつり合う。-The total flow rate required for each actuator 88, 88 is greater than or equal to the maximum discharge flow rate of the hydraulic pump 80. Now, the load pressure and the required flow rate of the actuator 88, 88 left actuator 88 is 100kg / cm 2, 501 / min , the right actuator 88 and 10kg / cm 2, 501 / min . When the maximum discharge flow rate of the hydraulic pump 80 is 1001 / min or more, the difference between the inlet pressure and the outlet pressure of the directional control valves 22, 22 is kept constant (= 20 kg / cm 2 ) as described above. , The flow rate can be controlled by the stroke, and the flow rate can be distributed by 501 / min. Next, assume that the stay discharge amount of the hydraulic pump 80 becomes 701 / min. Since the inlet pressure of the two directional control valves 22 and 22 are described above 120kg / cm 2, 30kg / c m 2, flow to the high pressure side of the directional control valve 22 is reduced to 201 / min from 501 / min. The flow rate to the low-pressure side directional control valve 22 remains at 501 / min. Assuming that the strokes (opening areas) of the two directional control valves 22 and 22 are not changed, the differential pressure between the inlet pressure and the outlet pressure of the directional control valve 22 on the high pressure side is reduced by 20 kg / cm 2 due to the decrease in the flow rate. Go down. Now, assume that the differential pressure is 14 kg / cm 2 , that is, the inlet pressure is reduced from 120 kg / cm 2 to 114 (100 + 14) kg / cm 2 . At this time, the pressures of the two pressure chambers 65 and 66 of the pressure reducing valve portion 24 of the pressure compensating valve 25 remain at 100 kg / cm 2 , and therefore the pressure reducing valve portion 24 is checked by the weak spring 69. If the pressure inside the pressure chamber b in the closing direction of the check valve portion 23 decreases from 120 kg / cm 2 to 114 kg / cm 2 , the check valve portion 23 remains open (stroke end). ), the direction of the pressure in the pressure chamber a to open the check valve unit 23, i.e., the pump discharge pressure is reduced to 120 kg / cm 2 or et 114 kg / cm 2. At this time (when the pump discharge flow rate is insufficient), the pump discharge pressure is not controlled by the pump adjustment directional control valve 85. On the other hand, the two pressure chambers 65 and 66 of the pressure reducing valve portion 24 of the pressure compensating valve 25 on the low pressure side remain 100 kg / cm 2 and 10 kg / cm 2 , and the differential pressure of 90 kg / cm 2 causes the check valve portion 63 to be Continue to push in the closing direction. On the other hand, since the pressure in the pressure chamber a in the opening direction of the check valve portion 23, that is, the pump discharge pressure is reduced to 114 kg / cm 2 , the pressure in the pressure chamber b in the closing direction of the check valve portion 23 is 30 kg / cm 2. The check valve portion 23 and the pressure reducing valve portion 24 balance the pressure in the state where the pressure is reduced from 2 to 24 kg / cm 2 . Therefore, the differential pressure between the inlet pressure and the outlet pressure of the directional control valve 22 on the low pressure side is reduced from 20 kg / cm 2 to 14 kg / cm 2 (24-10). Due to the decrease in the differential pressure of the directional control valve 22, the supply flow rate to the low-pressure side actuator 88 decreases from 501 / min, and the supply flow rate to the high-pressure side actuator 88 increases from 201 / min. That is, in the state where the differential pressure between the inlet pressure and the outlet pressure of the directional control valves 22 and 22 is equal, and the supply amounts to the two actuators 88, 88 are both divided into 351 / min, the hydraulic control system is controlled. Balance.

【００１２】 一つの油圧ポンプ８０によって負荷されるアクチュエータが３つ以上のとき 。 アクチュエータが３つ以上のときも、方向制御弁と油圧ポンプの間に、同じチ ェック弁部２３及び減圧弁部２４を備えた圧力補償弁２５を配設し、各減圧弁部 の閉じる方向の圧力差を負荷圧検出路８２によってすべて連通するだけで、アク チュエータが３つ以上のときも前述の作動原理による作動が実現される。When the number of actuators loaded by one hydraulic pump 80 is three or more. Even when there are three or more actuators, a pressure compensating valve 25 having the same check valve section 23 and pressure reducing valve section 24 is disposed between the directional control valve and the hydraulic pump, and the pressure compensating valve 25 in the closing direction of each pressure reducing valve section is arranged. Even if the number of actuators is three or more, the operation according to the above-described operation principle can be realized by simply communicating all the pressure differences through the load pressure detection path 82.

【００１３】[0013]

【考案が解決しようとする課題】[Problems to be solved by the device]

かかる圧力補償弁であると、油圧ポンプ２０の吐出圧油がチェック弁部２３よ り第１又は第２アクチュエータポート３４，３５に供給されている状態では、そ のチェック弁部２５のスプール６０は減圧弁部２４のスプール６４によってのみ 第１ポート３９とポンプポート４４を閉じる方向に押されるから、負荷の大きな アクチュエータを微速で作動させた後に負荷の小さなアクチュエータを全速で作 動しようとした瞬間に負荷の大きなアクチュエータの負荷圧が油圧ポンプ２０の 吐出路２１へ逆流し、負荷の大きなアクチュエータが負荷により一瞬動いてしま う。 With such a pressure compensating valve, the spool 60 of the check valve portion 25 is in a state where the discharge pressure oil of the hydraulic pump 20 is supplied from the check valve portion 23 to the first or second actuator ports 34, 35. Since the first port 39 and the pump port 44 are pushed in the direction of closing only by the spool 64 of the pressure reducing valve unit 24, the actuator with a large load is operated at a very low speed and then the actuator with a small load is operated at the full speed. The load pressure of the actuator with a large load flows backward to the discharge passage 21 of the hydraulic pump 20, and the actuator with a large load moves for a moment due to the load.

【００１４】 例えば図１において左側のアクチュエータ８８がパワーショベルのブームを上 げ下げするブームシリンダ、右側のアクチュエータ８８がパワーショベルのアー ムを上げ下げするシリンダ又は走行油圧モータとした場合に、左側の方向制御弁 ２２を微操作して油圧ポンプ２０の吐出圧油をブームシリンダの上げ室に供給す ることでブーム上げ動作し、次に右側の方向制御弁２２をフルストローク操作し た場合について説明すると、For example, when the actuator 88 on the left side in FIG. 1 is a boom cylinder that raises and lowers the boom of the power shovel, and the actuator 88 on the right side is a cylinder that raises and lowers the arm of the power shovel or a traveling hydraulic motor, the left direction A description will be given of the case where the control valve 22 is finely operated to supply the discharge pressure oil of the hydraulic pump 20 to the raising chamber of the boom cylinder to perform the boom raising operation, and then the right direction control valve 22 is fully stroked. ,

【００１５】 前述の左側の方向制御弁２２のスプール４９を微ストローク操作してポンプポ ート４４と第１アクチュエータポート３４を若干開口させると、その第１アクチ ュエータポート３４の圧力まで油圧ポンプ２０の吐出路２１の圧力が上昇し、チ ェック弁部２３の第１ポート３９の圧力が上昇するためにスプール６０が右方に 移動して第１ポート３９とポンプポート４４を開口させることで、油圧ポンプ２ ０の吐出圧油がブームシリンダの上げ室に供給されてブームを微速で上げ動作す る。この時、油圧ポンプ２０を駆動するエンジンは低速回転となって油圧ポンプ ２０の吐出量は少量となっている。When the spool 49 of the left side directional control valve 22 is slightly stroked to slightly open the pump port 44 and the first actuator port 34, the hydraulic pump 20 discharges up to the pressure of the first actuator port 34. The pressure in the passage 21 rises, and the pressure in the first port 39 of the check valve portion 23 rises, so that the spool 60 moves to the right to open the first port 39 and the pump port 44, thereby making the hydraulic pump 20 discharge pressure oil is supplied to the raising chamber of the boom cylinder to raise the boom at a slow speed. At this time, the engine that drives the hydraulic pump 20 rotates at a low speed, and the discharge amount of the hydraulic pump 20 is small.

【００１６】 この状態で右側の方向制御弁２２のスプール４９をフルストローク操作すると 油圧ポンプ２０の吐出量が少量のために油圧ポンプ２０の吐出圧油の全量が瞬間 負荷の小さなアームシリンダに流れる。 このアームシリンダに流れるのはアームシリンダ側（右側）の圧力補償弁２５ がブーム負荷圧により作動終了までの間である。In this state, when the spool 49 of the right direction control valve 22 is fully stroked, the discharge amount of the hydraulic pump 20 is small, so that the entire amount of the hydraulic oil discharged from the hydraulic pump 20 instantaneously flows to the arm cylinder having a small load. The flow to the arm cylinder is until the pressure compensating valve 25 on the arm cylinder side (right side) is operated by the boom load pressure.

【００１７】 このために、油圧ポンプ２０の吐出路２１の圧力は瞬間的に負荷の小さなアー ム負荷圧の圧力まで低下する。 この時、ブーム側の圧力補償弁２５の減圧弁部２４のスプール６４は第２負荷 圧検出ポート４６の負荷圧と第２圧力室６６の圧力でバランスし、チェック弁２ ３の第１ポート３９の圧力が低下すると同時にポンプポート４４の圧力も低下す るためにスプール６０が直ちに左方に動くことができない。 したがって、負荷の軽いアームシリンダを操作した瞬間ブームシリンダの負荷 圧がチェック弁部２３の第１ポート３９より油圧ポンプ２０の吐出路２１に逆流 し、ブームシリンダが一瞬縮少してブームが一瞬落下する。Therefore, the pressure in the discharge passage 21 of the hydraulic pump 20 instantaneously drops to the arm load pressure with a small load. At this time, the spool 64 of the pressure reducing valve portion 24 of the boom side pressure compensating valve 25 is balanced by the load pressure of the second load pressure detecting port 46 and the pressure of the second pressure chamber 66, and the first port 39 of the check valve 23. The pressure in the pump port 44 decreases at the same time as the pressure in the pump 60 decreases, so that the spool 60 cannot immediately move to the left. Therefore, at the moment when the arm cylinder with a light load is operated, the load pressure of the boom cylinder flows back to the discharge passage 21 of the hydraulic pump 20 from the first port 39 of the check valve unit 23, the boom cylinder contracts for a moment, and the boom falls for a moment. .

【００１８】 そこで、本考案は前述の課題を解決できるようにした圧力補償弁を提供するこ とを目的とする。Therefore, an object of the present invention is to provide a pressure compensating valve capable of solving the above problems.

【００１９】[0019]

【課題を解決するための手段】[Means for Solving the Problems]

弁ブロック３０にチェック弁用孔３７に開口した第１ポート３９及びチェック 弁用孔３７をポンプポート４４に連通する油路５６を形成し、そのチェック弁用 孔３７に第１ポート３９と油路５６を連通・遮断し、かつ遮断位置でストップさ れるスプール６０を挿入してチェック弁部２３とし、前記弁ブロック３０は減圧 弁用孔３８に開口する第２・第３ポート４２，４３を形成し、この減圧弁用孔３ ８に第２・第３ポート４２，４３を連通・遮断するスプール６４を嵌挿して第１ 圧力室６５と第２圧力室６６を形成し、その第１圧力室６５を負荷圧検出ポート に連通し、第２圧力室６６をで第３ポート４３に連通し、前記スプール６４をば ね６９で一方向に付勢して前記チェック弁部２３のスプール６０を遮断位置に押 しつけ保持して減圧弁部２４とし、前記第１・第２ポート３９，４２に油圧ポン プ２０の吐出路２１を接続し、前記第３ポート４３に負荷圧検出路８２を接続し た圧力補償弁において、前記チェック弁部２３のスプール６０を第１ポート３９ とポンプポート４４を遮断方向に押すスプリング１３１を設けた圧力補償弁。 弁ブロック３０にチェック弁用孔３７に開口した第１ポート３９及びチェック 弁用孔３７をポンプポート４４に連通する油路５６を形成し、そのチェック弁用 孔３７に第１ポート３９と油路５６を連通・遮断し、かつ遮断位置でストップさ れるスプール６０を挿入してチェック弁部２３とし、前記弁ブロック３０に減圧 弁用孔３８に開口する第２・第３ポート４２，４３を形成し、この減圧弁用孔３ ８に第２・第３ポート４２，４３を連通・遮断するスプール６４に嵌挿して第１ 圧力室６５と第２圧力室６６を形成し、その第１圧力室６５を負荷圧検出ポート に連通し、第２圧力室６６をで第３ポート４３に連通し、前記スプール６４をば ね６９で一方向に付勢して前記チェック弁部２３のスプール６０を遮断位置に押 しつけ保持して減圧弁部２４とし、前記第１・第２ポート３９，４２に油圧ポン プ２０の吐出路２１を接続し、前記第３ポート４３に負荷圧検出路８２を接続し た圧力補償弁において、前記チェック弁部２３のスプール６０に押杆１２１を設 け、この押杆１２１を第２圧力室６５に突出して減圧弁部２４のスプール６４に 当接した圧力補償弁。 The valve block 30 is provided with a first port 39 opened to the check valve hole 37 and an oil passage 56 for communicating the check valve hole 37 with the pump port 44, and the check valve hole 37 is provided with the first port 39 and the oil passage 56. The check valve portion 23 is formed by inserting the spool 60 that connects and shuts off 56 and is stopped at the shut-off position, and the valve block 30 forms the second and third ports 42 and 43 opening to the pressure reducing valve hole 38. Then, a spool 64 for communicating / blocking the second / third ports 42, 43 is fitted into the pressure reducing valve hole 38 to form a first pressure chamber 65 and a second pressure chamber 66. 65 communicates with the load pressure detection port, the second pressure chamber 66 communicates with the third port 43 by, and the spool 64 is urged in one direction by the spring 69 to shut off the spool 60 of the check valve portion 23. Hold in place In the pressure compensating valve having the pressure valve section 24, the discharge passage 21 of the hydraulic pump 20 connected to the first and second ports 39 and 42, and the load pressure detection passage 82 connected to the third port 43, A pressure compensation valve provided with a spring 131 that pushes the spool 60 of the valve portion 23 in the closing direction of the first port 39 and the pump port 44. The valve block 30 is provided with a first port 39 opened to the check valve hole 37 and an oil passage 56 for communicating the check valve hole 37 with the pump port 44, and the check valve hole 37 is provided with the first port 39 and the oil passage 56. A check valve portion 23 is formed by inserting a spool 60 that connects and shuts off 56 and is stopped at the shut-off position, and forms second and third ports 42 and 43 in the valve block 30 that open to the pressure reducing valve hole 38. Then, the first pressure chamber 65 and the second pressure chamber 66 are formed by fitting the spool 64 for communicating / blocking the second / third ports 42, 43 into the pressure reducing valve hole 38 to form the first pressure chamber 65 and the second pressure chamber 66. 65 communicates with the load pressure detection port, the second pressure chamber 66 communicates with the third port 43 by, and the spool 64 is urged in one direction by the spring 69 to shut off the spool 60 of the check valve portion 23. Hold in place In the pressure compensating valve having the pressure valve section 24, the discharge passage 21 of the hydraulic pump 20 connected to the first and second ports 39 and 42, and the load pressure detection passage 82 connected to the third port 43, A pressure compensation valve in which a pushing rod 121 is provided on the spool 60 of the valve portion 23, the pushing rod 121 is projected into the second pressure chamber 65 and abuts against the spool 64 of the pressure reducing valve portion 24.

【００２０】[0020]

【作 用】[Work]

チェック弁部２３のスプール６０はスプリング１３１で第１ポート３９とポン プポート４４を遮断する方向に押されているので、負荷の大きなアクチュエータ を微速動作し、次いで負荷の小さなアクチュエータを全速で動作した瞬間に油圧 ポンプ２０の吐出圧力が負荷の小さなアクチュエータの負荷圧まで低下した時に チェック弁部２３のスプール６０は直ちに第１ポート３９とポンプポート４４を 遮断する位置に移動して負荷の大きなアクチュエータの負荷圧が油圧ポンプの吐 出路２１に逆流することがなく、負荷の大きなアクチュエータが負荷によって一 瞬動くことを防止できる。 チェック弁部２３のスプール６０は押杆１２０に作用する負荷圧で第１ポート ３９とポンプポート４４を遮断する方向に押されているので、負荷の大きなアク チュエータを微速動作し、次いで負荷の小さなアクチュエータを全速で動作した 瞬間に油圧ポンプ２０の吐出圧力が負荷の小さなアクチュエータの負荷圧まで低 下した時にチェック弁部２３のスプール６０は直ちに第１ポート３９とポンプポ ート４４を遮断する位置に移動して負荷の大きなアクチュエータの負荷圧が油圧 ポンプ２０の吐出路２１に逆流することがなく、負荷の大きなアクチュエータが 負荷によって一瞬動くことを防止できる。 Since the spool 60 of the check valve unit 23 is pushed by the spring 131 in the direction to shut off the first port 39 and the pump port 44, the moment the actuator with a large load operates at a slight speed, and then the actuator with a small load operates at full speed. When the discharge pressure of the hydraulic pump 20 drops to the load pressure of the actuator with a small load, the spool 60 of the check valve portion 23 immediately moves to a position that shuts off the first port 39 and the pump port 44, and the load of the actuator with a large load is loaded. The pressure does not flow back into the discharge passage 21 of the hydraulic pump, and it is possible to prevent the actuator with a large load from momentarily moving due to the load. Since the spool 60 of the check valve portion 23 is pushed in the direction to shut off the first port 39 and the pump port 44 by the load pressure acting on the push rod 120, the actuator having a large load operates at a slight speed, and then the actuator having a small load operates. When the discharge pressure of the hydraulic pump 20 is reduced to the load pressure of the actuator with a small load at the moment when the actuator is operated at full speed, the spool 60 of the check valve unit 23 immediately moves to the position where it shuts off the first port 39 and the pump port 44. The load pressure of the actuator having a large load does not flow back into the discharge passage 21 of the hydraulic pump 20, and the actuator having a large load can be prevented from moving for a moment due to the load.

【００２１】[0021]

【実 施 例】【Example】

図３に示すように、チェック弁部２３のスプール６０に減圧弁部２４側に開口 した内孔１３０を形成し、減圧弁部２４のスプール６４の小径部７１の先端部７ １ａを内孔１３０内に臨ませ、その先端部２１ａと内孔１３０内にスプリング１ ３１を設けてスプール６０を第１ポート３９とポンプポート４４を閉じる方向に 付勢する。 As shown in FIG. 3, the spool 60 of the check valve portion 23 is formed with an inner hole 130 that opens toward the pressure reducing valve portion 24 side, and the tip portion 71 a of the small diameter portion 71 of the spool 64 of the pressure reducing valve portion 24 is formed into the inner hole 130. A spring 131 is provided in the front end portion 21a and in the inner hole 130 so as to urge the spool 60 in the direction of closing the first port 39 and the pump port 44.

【００２２】 これにより、前述のように負荷の大きなアクチュエータを微速動作し、次に負 荷の小さなアクチュエータを全速作動した瞬間に油圧ポンプ２０の吐出圧が負荷 の小さなアクチュエータの負荷圧まで低下すると、スプリング１３１でスプール ６０が直ちに第１ポート３９とポンプポート４４を遮断する位置に移動するから 負荷の大きなアクチュエータが負荷により一瞬動くことがない。As a result, as described above, when the actuator having a large load is operated at a slight speed, and then the discharge pressure of the hydraulic pump 20 is reduced to the load pressure of the actuator having a small load at the moment when the actuator having a small load is operated at full speed, The spring 131 immediately moves the spool 60 to a position where it blocks the first port 39 and the pump port 44, so that the actuator with a large load does not move for a moment due to the load.

【００２３】 図３において、減圧弁部２４のスプール６４の盲穴６７にフリーピストン６８ を嵌挿して圧力室１０２を形成し、前記スプール６４に第２ポート４２と第３ポ ート４３を連通・遮断するスリット状の開口１００を形成し、前記圧力室１０２ をダンパ用絞り１０３で前記開口１００に連通し、第２圧力室６６を細孔１０１ で第３ポート４３に連通してある。 また、前記チェック弁部２３を構成するスプール６０に小径部１０４を形成し て第１ポート３９と遮断した圧力室１０５を構成し、この圧力室１０５を油孔１ ０７ダンパ用絞り１０６で第１ポート３９に連通してある。In FIG. 3, the free piston 68 is fitted into the blind hole 67 of the spool 64 of the pressure reducing valve portion 24 to form the pressure chamber 102, and the second port 42 and the third port 43 are communicated with the spool 64. A slit-shaped opening 100 for blocking is formed, the pressure chamber 102 is communicated with the opening 100 by the damper diaphragm 103, and the second pressure chamber 66 is communicated with the third port 43 by the fine hole 101. Further, a small diameter portion 104 is formed on the spool 60 constituting the check valve portion 23 to form a pressure chamber 105 which is isolated from the first port 39, and the pressure chamber 105 is formed by the oil hole 107 damper throttle 106 as a first portion. It communicates with port 39.

【００２４】 図４は第２実施例を示し、チェック弁部２３のスプール６０に押杆１２０を減 圧弁部２４側に向けて一体的に設け、減圧弁部２４の押杆７１を廃止し、その押 杆１２０を透孔７２より第１圧力室６５に突出して減圧弁部２４のスプール６４ に当接してある。FIG. 4 shows a second embodiment, in which the push rod 120 is integrally provided on the spool 60 of the check valve portion 23 toward the pressure reducing valve portion 24 side, and the push rod 71 of the pressure reducing valve portion 24 is eliminated. The pushing rod 120 projects from the through hole 72 into the first pressure chamber 65 and abuts on the spool 64 of the pressure reducing valve portion 24.

【００２５】 このようにすれば、押杆１２０に第２圧力室６５の負荷圧が作用してスプール ６０を第１ポート３９とポンプポート４４を遮断する方向に押すので、前述のよ うに負荷の大きなアクチュエータを微速動作し、次に負荷の小さなアクチュエー タを全速作動した瞬間に油圧ポンプ２０の吐出圧が負荷の小さなアクチュエータ の負荷圧まで低下した時に押杆１２０に作用する負荷の大きなアクチュエータの 負荷圧によりスプール６０が直ちに第１ポート３９とポンプポート４４を遮断す る位置に移動するから負荷の大きなアクチュエータが負荷により一瞬動くことが ない。In this way, the load pressure of the second pressure chamber 65 acts on the push rod 120 and pushes the spool 60 in the direction of shutting off the first port 39 and the pump port 44. When a large actuator is operated at a slight speed and then an actuator with a small load is operated at full speed, when the discharge pressure of the hydraulic pump 20 drops to the load pressure of the actuator with a small load, the load of the actuator with a large load acting on the pushing rod 120 The pressure causes the spool 60 to immediately move to a position where it blocks the first port 39 and the pump port 44, so that the actuator with a large load does not move for a moment due to the load.

【００２６】[0026]

【考案の効果】[Effect of device]

チェック弁部２３のスプール６０はスプリング１３１で第１ポート３９とポン プポート４４を遮断する方向に押されているので、負荷の大きなアクチュエータ を微速動作し、次いで負荷の小さなアクチュエータを全速で動作した瞬間に油圧 ポンプ２０の吐出圧力が負荷の小さなアクチュエータの負荷圧まで低下した時に チェック弁部２３のスプール６０は直ちに第１ポート３９とポンプポート４４を 遮断する位置に移動して負荷の大きなアクチュエータの負荷圧が油圧ポンプ２０ の吐出路２１に逆流することがなく、負荷の大きなアクチュエータが負荷によっ て一瞬動くことを防止できる。 チェック弁部２３のスプール６０は押杆１２０に作用する負荷圧で第１ポート ３９とポンプポート４４を遮断する方向に押されているので、負荷の大きなアク チュエータを微速動作し、次いで負荷の小さなアクチュエータを全速で動作した 瞬間に油圧ポンプ２０の吐出圧力が負荷の小さなアクチュエータの負荷圧まで低 下した時にチェック弁部２３のスプール６０は直ちに第１ポート３９とポンプポ ート４４を遮断する位置に移動して負荷の大きなアクチュエータの負荷圧が油圧 ポンポ２０の吐出路２１に逆流することがなく、負荷の大きなアクチュエータが 負荷によって一瞬動くことを防止できる。 Since the spool 60 of the check valve unit 23 is pushed by the spring 131 in the direction to shut off the first port 39 and the pump port 44, the moment the actuator with a large load operates at a slight speed, and then the actuator with a small load operates at full speed. When the discharge pressure of the hydraulic pump 20 drops to the load pressure of the actuator with a small load, the spool 60 of the check valve portion 23 immediately moves to a position that shuts off the first port 39 and the pump port 44, and the load of the actuator with a large load is loaded. The pressure does not flow back into the discharge passage 21 of the hydraulic pump 20, and it is possible to prevent the actuator with a large load from moving for a moment due to the load. Since the spool 60 of the check valve portion 23 is pushed in the direction to shut off the first port 39 and the pump port 44 by the load pressure acting on the push rod 120, the actuator having a large load operates at a slight speed, and then the actuator having a small load operates. When the discharge pressure of the hydraulic pump 20 is reduced to the load pressure of the actuator with a small load at the moment when the actuator is operated at full speed, the spool 60 of the check valve unit 23 immediately moves to the position where it shuts off the first port 39 and the pump port 44. It is possible to prevent the load pressure of the actuator having a large load from moving back to the discharge passage 21 of the hydraulic pump 20 and moving the actuator having a large load for a moment due to the load.

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

【図１】従来の圧油供給装置の線図的構成説明図であ
る。FIG. 1 is a schematic diagram illustrating a conventional pressure oil supply device.

【図２】従来の圧油供給装置の断面図である。FIG. 2 is a cross-sectional view of a conventional pressure oil supply device.

【図３】本考案の第１実施例を示す断面図である。FIG. 3 is a sectional view showing a first embodiment of the present invention.

【図４】本考案の第２実施例を示す断面図である。FIG. 4 is a sectional view showing a second embodiment of the present invention.

【符号の説明】[Explanation of symbols]

２０…油圧ポンプ、２１…吐出路、２２…方向制御弁、
２３…チェック弁部、２４…減圧弁部、２５…圧力補償
弁、３０…弁ブロック、３１…スプール孔、３４…第１
アクチュエータポート、３５…第２アクチュエータポー
ト、３７…チェック弁用孔、３８…減圧弁用孔、３９…
第１ポート、４２…第２ポート、４３…第３ポート、４
４…ポンプポート、４５…第１負荷圧検出ポート、４６
…第２負荷圧検出ポート、４７…第１タンクポート、４
８…第２タンクポート、４９…主スプール、５３…第１
油路、５４…第２油路、５６…油孔、５８…油孔、６０
…スプール、６４…スプール、６５…第１圧力室、６６
…第２圧力室、６９…ばね、８２…負荷圧検出路、８８
…アクチュエータ、１２０…押杆、１３１…スプリン
グ。20 ... Hydraulic pump, 21 ... Discharge passage, 22 ... Direction control valve,
23 ... Check valve part, 24 ... Pressure reducing valve part, 25 ... Pressure compensation valve, 30 ... Valve block, 31 ... Spool hole, 34 ... First
Actuator port, 35 ... Second actuator port, 37 ... Check valve hole, 38 ... Pressure reducing valve hole, 39 ...
1st port, 42 ... 2nd port, 43 ... 3rd port, 4
4 ... Pump port, 45 ... First load pressure detection port, 46
… Second load pressure detection port, 47… First tank port, 4
8 ... Second tank port, 49 ... Main spool, 53 ... First
Oil passage, 54 ... Second oil passage, 56 ... Oil hole, 58 ... Oil hole, 60
... Spool, 64 ... Spool, 65 ... First pressure chamber, 66
... second pressure chamber, 69 ... spring, 82 ... load pressure detection path, 88
... actuator, 120 ... push rod, 131 ... spring.

Claims (3)

【実用新案登録請求の範囲】[Scope of utility model registration request] 【請求項１】 弁ブロック３０にチェック弁用孔３７に
開口した第１ポート３９及びチェック弁用孔３７をポン
プポート４４に連通する油路５６を形成し、そのチェッ
ク弁用孔３７に第１ポート３９と油路５６を連通・遮断
し、かつ遮断位置でストップされるスプール６０を挿入
してチェック弁部２３とし、 前記弁ブロック３０に減圧弁用孔３８に開口する第２・
第３ポート４２，４３を形成し、この減圧弁用孔３８に
第２・第３ポート４２，４３を連通・遮断するスプール
６４を嵌挿して第１圧力室６５と第２圧力室６６を形成
し、その第１圧力室６５を負荷圧検出ポートに連通し、
第２圧力室６６を第３ポート４３に連通し、前記スプー
ル６４をばね６９で一方向に付勢して前記チェック弁部
２３のスプール６０を遮断位置に押しつけ保持して減圧
弁部２４とし、前記第１・第２ポート３９，４２に油圧
ポンプ２０の吐出路２１を接続し、前記第３ポート４３
に負荷圧検出路８２を接続した圧力補償弁において、 前記チェック弁部２３のスプール６０を第１ポート３９
とポンプポート４４を遮断方向に押すスプリング１３１
を設けたことを特徴とする圧力補償弁。1. A valve block 30 is provided with a first port 39 opened in a check valve hole 37 and an oil passage 56 communicating the check valve hole 37 with a pump port 44, and the check valve hole 37 has a first port 39 formed therein. A second valve that opens and closes the port 39 and the oil passage 56 and a spool 60 that is stopped at the blocking position to form the check valve portion 23, and opens the pressure reducing valve hole 38 in the valve block 30.
The third port 42, 43 is formed, and the spool 64 for communicating and blocking the second and third ports 42, 43 is fitted into the pressure reducing valve hole 38 to form the first pressure chamber 65 and the second pressure chamber 66. Then, the first pressure chamber 65 is connected to the load pressure detection port,
The second pressure chamber 66 is communicated with the third port 43, and the spool 64 is biased in one direction by a spring 69 to press and hold the spool 60 of the check valve portion 23 at the shutoff position to form the pressure reducing valve portion 24. The discharge passage 21 of the hydraulic pump 20 is connected to the first and second ports 39 and 42, and the third port 43
In the pressure compensating valve in which the load pressure detecting path 82 is connected to, the spool 60 of the check valve portion 23 is connected to the first port 39.
131 for pushing the pump port 44 in the shut-off direction
A pressure compensating valve characterized by being provided. 【請求項２】 チェック弁２３のスプール６０に減圧弁
部２４に開口した内孔１３０を形成し、この内孔１３０
と減圧弁部２４のスプール６４との間にスプリング１３
１を設けた請求項１記載の圧力補償弁。2. The inner hole 130 opening to the pressure reducing valve portion 24 is formed in the spool 60 of the check valve 23, and the inner hole 130 is formed.
And the spool 64 of the pressure reducing valve portion 24 between the spring 13
The pressure compensation valve according to claim 1, wherein the pressure compensation valve is provided with 1. 【請求項３】 弁ブロック３０にチェック弁用孔３７に
開口した第１ポート３９及びチェック弁用孔３７をポン
プポート４４に連通する油路５６を形成し、そのチェッ
ク弁用孔３７に第１ポート３９と油路５６を連通・遮断
し、かつ遮断位置でストップされるスプール６０を挿入
してチェック弁部２３とし、 前記弁ブロック３０に減圧弁用孔３８に開口する第２・
第３ポート４２，４３を形成し、この減圧弁用孔３８に
第２・第３ポート４２，４３を連通・遮断するスプール
６４を嵌挿して第１圧力室６５と第２圧力室６６を形成
し、その第１圧力室６５を負荷圧検出ポートに連通し、
第２圧力室６６を第３ポート４３に連通し、前記スプー
ル６４をばね６９で一方向に付勢して前記チェック弁部
２３のスプール６０を遮断位置に押しつけ保持して減圧
弁部２４とし、前記第１・第２ポート３９，４２に油圧
ポンプ２０の吐出路２１を接続し、前記第３ポート４３
に負荷圧検出路８２を接続した圧力補償弁において、 前記チェック弁２３のスプール６０に押杆１２１を設
け、この押杆１２１を第２圧力室６５に突出して減圧弁
部２４のスプール６４に当接したことを特徴とする圧力
補償弁。3. The valve block 30 is provided with a first port 39 opened in the check valve hole 37 and an oil passage 56 communicating the check valve hole 37 with the pump port 44, and the check valve hole 37 is provided with a first port 39. A second valve that opens and closes the port 39 and the oil passage 56 and a spool 60 that is stopped at the blocking position to form the check valve portion 23, and opens the pressure reducing valve hole 38 in the valve block 30.
The third port 42, 43 is formed, and the spool 64 for communicating and blocking the second and third ports 42, 43 is fitted into the pressure reducing valve hole 38 to form the first pressure chamber 65 and the second pressure chamber 66. Then, the first pressure chamber 65 is connected to the load pressure detection port,
The second pressure chamber 66 is communicated with the third port 43, and the spool 64 is biased in one direction by a spring 69 to press and hold the spool 60 of the check valve portion 23 at the shutoff position to form the pressure reducing valve portion 24. The discharge passage 21 of the hydraulic pump 20 is connected to the first and second ports 39 and 42, and the third port 43
In the pressure compensating valve in which the load pressure detecting path 82 is connected to the spool 60 of the check valve 23, a push rod 121 is provided, and the push rod 121 projects into the second pressure chamber 65 and hits the spool 64 of the pressure reducing valve portion 24. A pressure compensation valve characterized by being in contact.
JP3584193U 1993-06-30 1993-06-30 Pressure compensation valve Pending JPH076501U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP3584193U JPH076501U (en) 1993-06-30 1993-06-30 Pressure compensation valve

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP3584193U JPH076501U (en) 1993-06-30 1993-06-30 Pressure compensation valve

Publications (1)

Publication Number Publication Date
JPH076501U true JPH076501U (en) 1995-01-31

Family

ID=12453209

Family Applications (1)

Application Number Title Priority Date Filing Date
JP3584193U Pending JPH076501U (en) 1993-06-30 1993-06-30 Pressure compensation valve

Country Status (1)

Country Link
JP (1) JPH076501U (en)

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