JPH041363Y2 - - Google Patents
Info
- Publication number
- JPH041363Y2 JPH041363Y2 JP4642784U JP4642784U JPH041363Y2 JP H041363 Y2 JPH041363 Y2 JP H041363Y2 JP 4642784 U JP4642784 U JP 4642784U JP 4642784 U JP4642784 U JP 4642784U JP H041363 Y2 JPH041363 Y2 JP H041363Y2
- Authority
- JP
- Japan
- Prior art keywords
- oil passage
- constant
- pilot
- valve
- reducing valve
- 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.)
- Expired
Links
- 239000007788 liquid Substances 0.000 claims description 10
- 239000012530 fluid Substances 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 2
- 230000007423 decrease Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
Landscapes
- Fluid-Pressure Circuits (AREA)
Description
【考案の詳細な説明】
（産業上の利用分野）
本考案は、油圧シリンダ等に可変絞りで定まる
一定流量を供給する流量制御回路に関し、特に零
流量に絞つたときにパイロツト系統の液圧消費を
少なくできるようにした流量制御回路に関する。[Detailed description of the invention] (Field of industrial application) The present invention relates to a flow rate control circuit that supplies a constant flow rate determined by a variable throttle to a hydraulic cylinder, etc., and particularly reduces the hydraulic pressure consumption of the pilot system when the flow rate is throttled to zero. This invention relates to a flow rate control circuit that can reduce the flow rate.
（考案の背景）
従来、この種の流量制御回路としては、例えば
第１図に示すものが開発されている。(Background of the Idea) Conventionally, as this type of flow control circuit, for example, the one shown in FIG. 1 has been developed.
第１図において、１はポンプ、２は油圧シリン
ダ、３は可変絞りであり、可変絞り３の設定開度
に応じた一定流量を得るために定差減圧弁部４を
設けている。 In FIG. 1, 1 is a pump, 2 is a hydraulic cylinder, and 3 is a variable throttle. In order to obtain a constant flow rate according to the set opening degree of the variable throttle 3, a constant difference pressure reducing valve section 4 is provided.
定差減圧弁部４は、可変絞り３の前後差圧ΔP
を一定に保つことで可変絞り３の開度に応じ常に
一定流量が得られる制御を行なつており、定差減
圧弁５、固定絞り６ａと定差減圧弁６ｂでなる定
流量制御弁６、及びシーケンス弁７で構成され
る。 The constant difference pressure reducing valve section 4 is configured to adjust the differential pressure ΔP across the variable throttle 3.
By keeping constant the constant flow rate, a constant flow rate is controlled according to the opening degree of the variable throttle 3, and the constant flow rate control valve 6 is made up of a constant difference pressure reducing valve 5, a fixed throttle 6a, and a constant difference pressure reducing valve 6b. and a sequence valve 7.
また、制御液圧はポンプ１でアキユームレータ
８を加圧し、アキユームレータ８の蓄積圧力で油
圧シリンダ１や他の液圧消費装置９を作動する方
式を取つており、図示のリリーフ弁１０のオンロ
ード状態でアキユームレータ８に液圧を蓄え、設
定圧力に達すると圧力スイツチ１１が働いて切換
弁１２の作動でリリーフ弁１０がアンロード状態
となり、ポンプ１を無負荷運転としてエネルギ消
費の節減を図つている。尚、１３はアンロード状
態で主油路をポンプ１側から分離するチエツク弁
である。 The control hydraulic pressure is controlled by pressurizing the accumulator 8 with the pump 1, and using the accumulated pressure of the accumulator 8 to operate the hydraulic cylinder 1 and other hydraulic pressure consuming devices 9. When the hydraulic pressure is stored in the accumulator 8 in the on-load state, and the set pressure is reached, the pressure switch 11 is activated and the switching valve 12 is activated, causing the relief valve 10 to become unloaded, causing the pump 1 to operate without load and consuming energy. We are trying to save money. Note that 13 is a check valve that separates the main oil passage from the pump 1 side in the unloaded state.
しかしながら、このような従来の流量制御回路
にあつては、可変絞り３を全閉としても、定差減
圧弁部４における定流量制御弁６による一定流量
がシーケンス弁７を通つて負荷側へ常時流れ、負
荷の停止状態でもパイロツト系統によるアキユー
ムレータの液圧消費が行なわれ、この負荷停止時
の液圧消費を補うためにアキユームレータの容量
を大きくしなければならず、設備装置が大型化
し、またアキユームレータの利用によるエネルギ
節減の効果が充分に発揮できないという問題があ
つた。 However, in such a conventional flow rate control circuit, even if the variable throttle 3 is fully closed, the constant flow rate from the constant flow rate control valve 6 in the constant difference pressure reducing valve section 4 always flows through the sequence valve 7 to the load side. The pilot system consumes hydraulic pressure in the accumulator even when the flow and load are stopped, and the capacity of the accumulator must be increased to compensate for the hydraulic pressure consumption when the load is stopped, which requires large equipment. There was also the problem that the energy saving effect of using an accumulator could not be fully demonstrated.
（考案の目的）
本考案は、このような従来の問題点に鑑みてな
されたもので、可変絞りを全閉としたときにはパ
イロツト系統についても液の流れを確実に遮断し
て負荷停止時の液圧消費を少なくできるようにし
た液圧制御回路を提供することを目的とする。(Purpose of the invention) The present invention was made in view of these conventional problems. When the variable throttle is fully closed, the flow of liquid in the pilot system is also reliably shut off, and the liquid flow is maintained even when the load is stopped. It is an object of the present invention to provide a hydraulic pressure control circuit that can reduce pressure consumption.
（考案の構成および作用）
この目的を達成するため本考案は、アキユーム
レータを有する液圧源から負荷への主油路に、定
差減圧弁部と可変絞りを配置し、可変絞りについ
て主油路及び定差減圧弁部へのパイロツト油路を
連動して開閉する開閉部を設け、この開閉部を介
して定差減圧弁部へパイロツト系統の液を供給
し、可変絞りを全閉とした時には開閉部で主油路
及びパイロツト油路を液圧源から遮断して定差減
圧弁部へのパイロツト液の供給を停止し、負荷停
止状態でのパイロツト系統による液圧消費を防止
するようにしたものである。(Structure and operation of the device) In order to achieve this objective, the present invention arranges a constant difference pressure reducing valve part and a variable throttle in the main oil passage from a hydraulic pressure source having an accumulator to a load, and the variable throttle is An opening/closing part is provided that opens and closes the oil passage and the pilot oil passage to the constant difference pressure reducing valve part in conjunction with each other, and the liquid of the pilot system is supplied to the constant difference pressure reducing valve part through this opening/closing part, and the variable throttle is fully closed. When this occurs, the main oil passage and pilot oil passage are shut off from the hydraulic pressure source at the opening/closing section to stop the supply of pilot fluid to the constant differential pressure reducing valve section, thereby preventing fluid pressure consumption by the pilot system when the load is stopped. This is what I did.
（考案の効果）
このような本考案の構成及び作用によれば、可
変絞りを全閉にすると主油路はもちろんのことパ
イロツト油路についても液の流れを遮断すること
ができ、液圧源にアキユームレータを使用してい
ても、負荷停止時の無駄な液圧消費を防止し、油
圧装置のエネルギ効率を向上することができる。(Effect of the invention) According to the structure and operation of the present invention, when the variable throttle is fully closed, the flow of liquid can be blocked not only in the main oil passage but also in the pilot oil passage, and the liquid pressure source Even if an accumulator is used, wasteful consumption of hydraulic pressure when the load is stopped can be prevented and the energy efficiency of the hydraulic system can be improved.
また、負荷停止状態での液圧消費がないことか
ら、アキユームレータの容量が小型で済み、設備
の小型化とコストの低減を図ることができる。 Furthermore, since there is no hydraulic pressure consumption when the load is stopped, the capacity of the accumulator can be kept small, making it possible to downsize the equipment and reduce costs.
更に、負荷停止時の液圧消費がないので単一の
液圧源で多数の負荷を制御することができ、設備
効率を高めることができる。 Furthermore, since there is no hydraulic pressure consumption when the load is stopped, multiple loads can be controlled with a single hydraulic pressure source, increasing equipment efficiency.
（実施例）
第２図は本考案の一実施例を示した回路図であ
る。(Embodiment) FIG. 2 is a circuit diagram showing an embodiment of the present invention.
まず、構成を説明すると、１はポンプ、２は油
圧シリンダであり、ポンプ１からチエツク弁１３
を介して油圧シリンダ２に至る実線で示す主油路
にポンプ１側より定差減圧弁部１４及び電磁比例
式可変絞り部１５を順次配設している。定差減圧
弁部１４は第１図の従来装置と同じ定差減圧弁
５、固定絞り６ａと定差減圧弁６ｂで構成された
定流量制御弁６と、シーケンス弁７を備えてい
る。 First, to explain the configuration, 1 is a pump, 2 is a hydraulic cylinder, and from the pump 1 to the check valve 13
A constant difference pressure reducing valve section 14 and an electromagnetic proportional variable throttle section 15 are sequentially arranged from the pump 1 side in the main oil path shown by the solid line that reaches the hydraulic cylinder 2 via the pump 1 side. The constant difference pressure reducing valve unit 14 includes the same constant difference pressure reducing valve 5 as in the conventional device shown in FIG. 1, a constant flow control valve 6 composed of a fixed throttle 6a and a constant difference pressure reducing valve 6b, and a sequence valve 7.
一方、電磁比例式可変絞り部１５は１５ａ，１
５ｂ，１５ｃの三切換位置をもち、主油路のポー
トＡとＢ及びパイロツト用のポートＣとＤを切り
換え、図示の切換位置１５ａで主油路及びパイロ
ツト油路を切り放した全閉位置にあり、切換位置
１５ｃでは主油路及びパイロツト油路を接続し、
主油路については外部からのパイロツト圧力に応
じた電磁比例制御で流量を調整する位置となる。
また、中央の切換位置１５ｂは１５ａから１５ｃ
へ切り換える途中の過程を示し、まずパイロツト
油路のポート接続が行なわれる状態を示してい
る。 On the other hand, the electromagnetic proportional variable aperture section 15 has 15a, 1
It has three switching positions 5b and 15c, and switches ports A and B of the main oil passage and ports C and D for the pilot, and is in a fully closed position with the main oil passage and pilot oil passage disconnected at the switching position 15a shown in the figure. , at the switching position 15c, the main oil passage and the pilot oil passage are connected,
As for the main oil passage, the flow rate is adjusted using electromagnetic proportional control according to external pilot pressure.
Moreover, the central switching position 15b is from 15a to 15c.
The figure shows the process of switching to the 1st position, and first shows the state in which the port connection of the pilot oil passage is performed.
この様に主油路及びパイロツト油路を連動して
開閉する開閉部としての切換位置１５ａ，１５ｂ
及び１５ｃを備えた電磁比例式可変絞り部１５の
パイロツトポートＤに液圧源からのパイロツト油
路１６を接続しており、電磁比例式可変絞り部１
５が切換位置１５ｂ及び１５ｃに切り換わつた
時、パイロツトポートＣより、パイロツト油路１
７を介して、定差減圧弁部１４に液を供給するよ
うにしている。 In this way, switching positions 15a and 15b serve as opening/closing parts that open and close the main oil passage and the pilot oil passage in conjunction with each other.
A pilot oil passage 16 from a hydraulic pressure source is connected to the pilot port D of the electromagnetic proportional variable throttle section 15, which is equipped with an electromagnetic proportional variable throttle section 15c.
5 is switched to the switching positions 15b and 15c, the pilot oil passage 1 is opened from the pilot port C.
7, the liquid is supplied to the constant difference pressure reducing valve section 14.
次に、定差減圧弁部１４の構成を詳細に説明す
ると、電磁比例式可変絞り部１５からのパイロツ
ト油路１７は定流量制御弁６に接続され、定流量
制御弁６は主油路に設けた定差減圧弁のスプリン
グ５ａを備えた二次パイロツト室に一定流量の液
を供給しており、また定差減圧弁５の一次パイロ
ツト室には電磁比例式可変絞り部１５の入口圧力
が与えられている。シーケンス弁７は、定差減圧
弁５のスプリング５ａを備えた二次パイロツト室
とタンク１８の間に接続され、電磁比例式可変絞
り部１５の前後差圧をパイロツト油路１９，２０
により制御油圧として接続している。 Next, to explain the configuration of the constant difference pressure reducing valve section 14 in detail, the pilot oil passage 17 from the electromagnetic proportional variable throttle section 15 is connected to the constant flow control valve 6, and the constant flow control valve 6 is connected to the main oil passage. A constant flow rate of liquid is supplied to the secondary pilot chamber equipped with the spring 5a of the constant difference pressure reducing valve 5, and the inlet pressure of the electromagnetic proportional variable restrictor 15 is supplied to the primary pilot chamber of the constant difference pressure reducing valve 5. It is given. The sequence valve 7 is connected between the secondary pilot chamber equipped with the spring 5a of the constant difference pressure reducing valve 5 and the tank 18, and controls the differential pressure across the electromagnetic proportional variable restrictor 15 to the pilot oil passages 19, 20.
It is connected as a control hydraulic pressure.
さらに液圧源は第１図の従来例と同様にアキユ
ームレータ８を使用した方式であり、リリーフ弁
１０が閉じた図示のオンロード状態でチエツク弁
１３を介してアキユームレータ８に液圧を蓄積さ
せ、アキユームレータ８の液圧が所定圧に達する
と、圧力スイツチ１１が作動して切換弁１３によ
りリリーフ弁１０をアンロード状態とし、このア
ンロード状態でポンプ１は無負荷運転を行なうよ
うになる。勿論、アキユームレータ８の液圧が消
費されて圧力スイツチ１１がもどると、リリーフ
弁１０が再びオンロード状態となり、ポンプ１に
よるアキユームレータ８の液圧回復が行なわれ、
さらにチエツク弁１３の二次側には電磁弁や油圧
シリンダなどで構成される他の液圧消費装置９が
接続されている。 Furthermore, the hydraulic pressure source uses the accumulator 8 as in the conventional example shown in FIG. When the hydraulic pressure in the accumulator 8 reaches a predetermined pressure, the pressure switch 11 is activated and the switching valve 13 sets the relief valve 10 in the unloaded state, and in this unloaded state, the pump 1 operates without load. I will start doing it. Of course, when the hydraulic pressure of the accumulator 8 is consumed and the pressure switch 11 is returned to its original state, the relief valve 10 becomes on-load again, and the hydraulic pressure of the accumulator 8 is restored by the pump 1.
Furthermore, another hydraulic pressure consuming device 9 consisting of a solenoid valve, a hydraulic cylinder, etc. is connected to the secondary side of the check valve 13.
次に、第２図の実施例を動作を説明する。 Next, the operation of the embodiment shown in FIG. 2 will be explained.
第２図の電磁比例式可変絞り部１５は、全閉状
態を示しており、全閉状態で切換位置１５ａに切
り換わつて、主油路のポートＡとＢ及び、パイロ
ツト油路のポートＣとＤを遮断しており、油圧シ
リンダ２に対する液圧供給を停止すると同時に、
パイロツト油路１７による定差減圧弁部１４への
パイロツト液圧の供給も遮断している。この全閉
状態のにおいて定差減圧弁部１４ではシーケンス
弁７が電磁比例式可変絞り部１５の前後差圧（回
路圧）を受けてタンク１８に回路を開いており、
もし電磁比例式可変絞り部１５でパイロツト油路
の遮断が行なわれていないと、定流量制御弁６に
よる一定流量が常にシーケンス弁７を介してタン
ク１８に流れることになり、電磁比例式可変絞り
部１５の全閉状態でもアキユームレータ８の液圧
消費が行なわれてしまう。 The electromagnetic proportional variable restrictor 15 in FIG. 2 is shown in a fully closed state. In the fully closed state, it is switched to the switching position 15a, and the ports A and B of the main oil passage and the port C of the pilot oil passage are switched to the switching position 15a. and D are shut off, and at the same time, the hydraulic pressure supply to the hydraulic cylinder 2 is stopped.
The supply of pilot hydraulic pressure to the constant difference pressure reducing valve section 14 through the pilot oil passage 17 is also cut off. In this fully closed state, in the constant differential pressure reducing valve section 14, the sequence valve 7 receives the differential pressure (circuit pressure) across the electromagnetic proportional variable throttle section 15 and opens a circuit to the tank 18.
If the pilot oil passage is not shut off by the electromagnetic proportional variable restrictor 15, the constant flow rate from the constant flow control valve 6 will always flow to the tank 18 via the sequence valve 7, and the electromagnetic proportional variable restrictor will Even when the section 15 is fully closed, the hydraulic pressure of the accumulator 8 is consumed.
しかしながら、本考案にあつては定差減圧弁部
１４にパイロツト液圧を供給するパイロツト油路
を電磁比例式可変絞り部１５の全閉位置で遮断し
ているため、シーケンス弁７が開いていても、定
差減圧弁部１４に対する液の供給が行なわれず、
絞り全閉状態においてアキユームレータの無駄な
液圧消費が防止できる。次に、電磁比例式可変絞
り部１５の所定の設定流量を与える切換位置１５
ｃに切り換えると、この切換途中における切換位
置１５ｂでまずパイロツトポートＤとＣが連通し
て定差減圧弁部１４にパイロツト用の液が供給さ
れ、可変絞りが開く時には、常に定差減圧弁部１
４が正常な動作状態となつている。従つて、電磁
比例式可変絞り部１５が切換位置１５ｃの絞り位
置に切換つた時には定差減圧弁部１４により、絞
り部１５の前後差圧を一定に保つて、設定流量を
正確に油圧シリンダ２に供給する流量制御状態を
つくりだす。 However, in the present invention, since the pilot oil passage supplying pilot hydraulic pressure to the constant difference pressure reducing valve section 14 is shut off at the fully closed position of the electromagnetic proportional variable throttle section 15, the sequence valve 7 is open. Also, the liquid is not supplied to the constant differential pressure reducing valve section 14,
It is possible to prevent wasteful consumption of hydraulic pressure in the accumulator when the throttle is fully closed. Next, the switching position 15 provides a predetermined set flow rate of the electromagnetic proportional variable restrictor 15.
When switching to c, the pilot ports D and C are first communicated at the switching position 15b in the middle of this switching, and pilot fluid is supplied to the constant differential pressure reducing valve section 14, and when the variable throttle opens, the constant differential pressure reducing valve section is always closed. 1
4 is in normal operating condition. Therefore, when the electromagnetic proportional variable throttle section 15 switches to the switching position 15c, the constant differential pressure reducing valve section 14 maintains the differential pressure across the throttle section 15 constant, and accurately adjusts the set flow rate to the hydraulic cylinder 2. Creates a flow rate control condition that supplies the
すなわち、可変絞り部１５の開度を設定流量が
得られる開度に開いた状態で主油路に油を流して
いる時に、負荷への供給流量が増加したとする
と、可変絞り部１５の前後差圧も増加する。この
可変絞り部１５の前後差圧はシーケンス弁７にパ
イロツト圧として加わつており、差圧による力が
差圧設定スプリングのスプリング力に達するとシ
ーケンス弁７が切換つて油路を開き、定流量制御
弁６よりの一定流量をシーケンス弁７を介してタ
ンク１８に流す。このため、定差減圧弁５の二次
側パイロツト室の圧力が下がり、定差減圧弁５の
圧力補償スプールを圧力補償オリフイスを閉じる
方向に移動させてバランスし、このため可変絞り
部１５を流れる流量が絞られて前後差圧を設定流
量に応じた一定値に押え込むようになり、可変絞
り部１５の前後差圧が常に一定に保つことでシリ
ンダ負荷に対し可変絞り部１５で設定した一定の
流量を供給することが出来る。 In other words, if the flow rate supplied to the load increases while oil is flowing through the main oil passage with the variable throttle part 15 opened to the degree where the set flow rate is obtained, the flow rate before and after the variable throttle part 15 increases. Differential pressure also increases. The differential pressure across the variable restrictor 15 is applied to the sequence valve 7 as a pilot pressure, and when the force due to the differential pressure reaches the spring force of the differential pressure setting spring, the sequence valve 7 switches to open the oil passage and perform constant flow control. A constant flow rate from valve 6 is sent to tank 18 via sequence valve 7. Therefore, the pressure in the secondary pilot chamber of the constant difference pressure reducing valve 5 decreases, and the pressure compensating spool of the constant difference pressure reducing valve 5 is moved in the direction of closing the pressure compensating orifice to achieve balance. The flow rate is throttled and the differential pressure across the front and back is suppressed to a constant value according to the set flow rate, and by keeping the differential pressure across the variable throttle section 15 constant, the constant pressure set by the variable throttle section 15 against the cylinder load is maintained. It is possible to supply a flow rate of
第３図は本考案の他の実施例を示した回路図で
あり、この実施例は定差減圧弁部１４に設けたシ
ーケンス弁７の二次側をパイロツト油路２０を介
して油圧シリンダの流入側、即ち、電磁比例式可
変絞り部１５の出口側に接続したことを特徴と
し、この実施例においても、定差減圧弁部１４に
供給するパイロツト液圧は電磁比例式可変絞り部
１５りの開閉部を介して行なわれるため、図示の
電磁比例式可変絞り部１５の全閉位置で液圧源か
らのパイロツト油路１６と定差減圧弁部１４にパ
イロツト液を供給するパイロツト油路１７の接続
が遮断され、絞り全閉状態におけるアキユームレ
ータ８の液圧消費を防止することができる。 FIG. 3 is a circuit diagram showing another embodiment of the present invention, in which the secondary side of the sequence valve 7 provided in the constant difference pressure reducing valve section 14 is connected to the hydraulic cylinder via the pilot oil passage 20. It is characterized in that it is connected to the inflow side, that is, the outlet side of the electromagnetic proportional variable throttle section 15. Also in this embodiment, the pilot fluid pressure supplied to the constant difference pressure reducing valve section 14 is connected to the electromagnetic proportional variable throttle section 15. Since this is carried out through the opening/closing part of the electromagnetic proportional variable throttle part 15 shown in the figure, the pilot oil passage 17 supplies pilot fluid from the hydraulic pressure source to the pilot oil passage 16 and the constant difference pressure reducing valve part 14. connection is cut off, and hydraulic pressure consumption of the accumulator 8 in the throttle fully closed state can be prevented.
さらにシーケンス弁７の二次側を油圧シリンダ
２への主油路に接続しているため、パイロツト油
路２２は定流量制御弁６からの流れがあり、油路
中の混入空気は除去され易く、電磁比例式可変絞
り部１５を絞り位置に切り換えた時のパイロツト
液圧の供給遅れがなく、絞り位置への切換えで速
やかに定差減圧弁部１４による一定流量の制御状
態をつくり出すことができる。 Furthermore, since the secondary side of the sequence valve 7 is connected to the main oil path to the hydraulic cylinder 2, the pilot oil path 22 has a flow from the constant flow control valve 6, and air mixed in the oil path is easily removed. There is no delay in the supply of pilot fluid pressure when the electromagnetic proportional variable throttle section 15 is switched to the throttle position, and a constant flow rate control state can be quickly created by the constant difference pressure reducing valve section 14 by switching to the throttle position. .
尚、第３図の実施例における他の構成は第２図
の実施例と同じであることから、同じ番号を付し
てその説明は省略する。 It should be noted that the other configurations in the embodiment shown in FIG. 3 are the same as those in the embodiment shown in FIG. 2, so the same reference numerals are given and the explanation thereof will be omitted.
第１図は従来例を示した回路図、第２図は本考
案の一実施例を示した回路図、第３図は本考案の
他の実施例を示した回路図である。
１……ポンプ、２……油圧シリンダ、５……定
差減圧弁、６……定流量制御弁、６ａ……固定絞
り、６ｂ……定差減圧弁、７……シーケンス弁、
８……アキユームレータ、９……液圧消費装置、
１０……リリーフ弁、１１……圧力スイツチ、１
２……切換弁、１３……チエツク弁、１４……定
差減圧弁部、１５……電磁比例式可変絞り部、１
５ａ，１５ｂ，１５ｃ……切換位置、１６，１
７，１９，２０……パイロツト油路、１８……タ
ンク。
FIG. 1 is a circuit diagram showing a conventional example, FIG. 2 is a circuit diagram showing one embodiment of the present invention, and FIG. 3 is a circuit diagram showing another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Pump, 2... Hydraulic cylinder, 5... Constant difference pressure reducing valve, 6... Constant flow control valve, 6a... Fixed throttle, 6b... Constant difference pressure reducing valve, 7... Sequence valve,
8... Accumulator, 9... Hydraulic pressure consumption device,
10... Relief valve, 11... Pressure switch, 1
2...Switching valve, 13...Check valve, 14...Constant differential pressure reducing valve section, 15...Electromagnetic proportional variable throttle section, 1
5a, 15b, 15c...Switching position, 16, 1
7, 19, 20... Pilot oil line, 18... Tank.
Claims (1)
次パイロツト室に導入し二次パイロツト室にスプ
リングを収納した定差減圧弁と、 前記主油路の負荷側に配置され、液圧源からの
主油路とパイロツト油路を連動して開閉する開閉
部を備えた可変絞りと、 該可変絞りのパイロツト側開閉部から一定流量
の液を前記定差減圧弁の二次パイロツト室に向け
て供給する定流量制御弁と、 前記定差減圧弁の二次パイロツト室に接続さ
れ、前記定流量制御弁からの液を流出させると共
に前記可変絞りの前後差圧がパイロツト制御圧と
して導入したシーケンス弁とを備えたことを特徴
とする流量制御回路。[Claims for Utility Model Registration] A main oil passage that connects a hydraulic pressure source to a load; a variable throttle disposed on the load side of the main oil passage and having an opening/closing part that opens and closes the main oil passage from the hydraulic pressure source and the pilot oil passage in conjunction with each other; a constant flow control valve that supplies a constant flow rate of liquid from a pilot side opening/closing part toward a secondary pilot chamber of the constant difference pressure reducing valve; and a constant flow control valve that is connected to the secondary pilot chamber of the constant difference pressure reducing valve. 1. A flow control circuit comprising: a sequence valve that allows liquid to flow out from the valve and introduces a differential pressure across the variable throttle as a pilot control pressure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4642784U JPS60158001U (en) | 1984-03-30 | 1984-03-30 | flow control circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4642784U JPS60158001U (en) | 1984-03-30 | 1984-03-30 | flow control circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60158001U JPS60158001U (en) | 1985-10-21 |
| JPH041363Y2 true JPH041363Y2 (en) | 1992-01-17 |
Family
ID=30560806
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4642784U Granted JPS60158001U (en) | 1984-03-30 | 1984-03-30 | flow control circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60158001U (en) |
-
1984
- 1984-03-30 JP JP4642784U patent/JPS60158001U/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS60158001U (en) | 1985-10-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| GB2406618A (en) | Pump unloading arrangement | |
| JPH0495601A (en) | Pilot pressure control circuit of selector valve in actuator drive circuit | |
| JPH041363Y2 (en) | ||
| JP3768566B2 (en) | Hydraulic pump discharge flow control device | |
| JPH0384204A (en) | Confluence valve device for load sensing type hydraulic circuit | |
| JP3708711B2 (en) | Hydraulic control device | |
| JPH05202858A (en) | Closed loop control circuit for variable head pump | |
| JPH0483908A (en) | Hydraulic control circuit | |
| JP2002276607A (en) | Hydraulic control device | |
| JPH01275902A (en) | Discharge rate control circuit for load pressure compensating pump | |
| US5140815A (en) | Valve apparatus | |
| JPH0310802B2 (en) | ||
| JPH01312201A (en) | Hydraulic flow controller | |
| JP3667037B2 (en) | Solenoid valve hydraulic control circuit | |
| JP2652791B2 (en) | Flow control device | |
| JP2639554B2 (en) | Hydraulic equipment | |
| JP3667035B2 (en) | Hydraulic control device | |
| WO1995017609A1 (en) | Unloading device for a hydraulic circuit | |
| JPS605121Y2 (en) | fluid equipment | |
| JP3558862B2 (en) | Hydraulic system | |
| JP3667036B2 (en) | Hydraulic control circuit | |
| JP2514159Y2 (en) | Flow control valve | |
| KR970011610B1 (en) | Load sensing type liquid pressure system in a heavy working machine | |
| JPH0219321B2 (en) | ||
| JPH04258513A (en) | Hydraulic control circuit |