JPS5830152Y2 - How to use the pump - Google Patents
How to use the pumpInfo
- Publication number
- JPS5830152Y2 JPS5830152Y2 JP10635574U JP10635574U JPS5830152Y2 JP S5830152 Y2 JPS5830152 Y2 JP S5830152Y2 JP 10635574 U JP10635574 U JP 10635574U JP 10635574 U JP10635574 U JP 10635574U JP S5830152 Y2 JPS5830152 Y2 JP S5830152Y2
- Authority
- JP
- Japan
- Prior art keywords
- pressure
- valve
- pilot
- displacement pump
- relief
- 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
Landscapes
- Reciprocating Pumps (AREA)
- Fluid-Pressure Circuits (AREA)
Description
【考案の詳細な説明】
本考案は、可変容量形ポンプの自動負荷軽減装置の改良
に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an automatic load reduction device for a variable displacement pump.
従来、建設機械等において、油圧駆動装置の原動機の出
力を有効に利用する目的で、馬力補償機構ないしアクチ
ュエータ休止時に管路系に生じる馬力損失を低減するた
めの流量制御機構を併設した可変容量形ポンプが採用さ
れている。Conventionally, in construction machinery, etc., in order to effectively utilize the output of the prime mover of a hydraulic drive device, a variable displacement type is equipped with a horsepower compensation mechanism or a flow control mechanism to reduce horsepower loss that occurs in the pipeline system when the actuator is stopped. A pump is used.
これをたとえば第１図に示すものについて説明すると、
このものは、可変容量形ポンプ１とアクチュエータ（図
示せず）とを結ぶ管路２にセンタバイパス型の方向切換
弁３，４．５およびポンプ吐出圧を制限するリリーフ弁
６を各配設し、リリーフ弁６の排出側および方向切換弁
３，４．５のバイパス管路７と戻り管路８はともにタン
ク９に連通し、方向切換弁の数だけ並設されたリモコン
弁１１は、操作レバー１３で操作される可変減圧弁１８
．２１の各入口ポートを管路１０で定容量形ポンプ１２
に、可変減圧弁１８．２１の出口ポートをそれぞれパイ
ロット管路２２．２３で方向切換弁のパイロット室１５
．１６に、各接続してあり、このパイロット管路２２と
２３は背向する一対のチェック弁２４．２５を介装した
管路２６で連結するとともに、この管路２６のチェンチ
弁２４と２５の間よりパイロット管路２８を分岐し、こ
のパイロット管路２８および管路２から分岐したパイロ
ット管路１７をそれぞれ可変容量形ポンプ１のレギュレ
ータ１４に各接続しである。To explain this for example as shown in Figure 1,
In this pump, a center bypass type directional control valve 3, 4.5 and a relief valve 6 for limiting the pump discharge pressure are arranged in a pipe line 2 connecting a variable displacement pump 1 and an actuator (not shown). , the discharge side of the relief valve 6 and the bypass line 7 and return line 8 of the directional control valves 3, 4.5 both communicate with the tank 9, and the remote control valves 11 arranged in parallel as many as the directional control valves are operated. Variable pressure reducing valve 18 operated by lever 13
．． Each inlet port of 21 is connected to a fixed displacement pump 12 via a conduit 10.
The outlet ports of the variable pressure reducing valves 18, 21 are respectively connected to the pilot chamber 15 of the directional valve via pilot lines 22, 23.
．． These pilot lines 22 and 23 are connected by a line 26 which has a pair of opposite check valves 24 and 25 interposed therebetween, and the check valves 24 and 25 of this line 26 are connected to each other. A pilot pipe line 28 is branched from between, and this pilot pipe line 28 and a pilot pipe line 17 branched from the pipe line 2 are respectively connected to the regulator 14 of the variable displacement pump 1.
そのため、リモコン弁１１の操作レバー１３が図示の如
く中立位置にあるとき、定容量形ポンプ１２の吐出圧は
方向切換弁３，４．５およびレギュレータ１４に作用し
ないため、アクチュエータ休止時のポンプ吐出量は最小
となり、管路系による馬力損失を低減する。Therefore, when the operating lever 13 of the remote control valve 11 is in the neutral position as shown in the figure, the discharge pressure of the constant displacement pump 12 does not act on the directional control valves 3, 4.5 and the regulator 14, so that the pump discharge when the actuator is stopped is volume is minimized, reducing horsepower losses through the piping system.
また、操作レバー１３をθだげ図示矢印方向に倒すと、
管路１０とパイロット管路２２が連通してレバー１３の
操作角度θに応じたパイロット圧が可変容量形ポンプ１
のレギュレータ１４および方向切換弁３のパイロット室
１５に作用し、方向切換弁３を位置Ａから位置Ｂに切換
えるとともにポンプ傾転角を増大させアクチュエータ（
図示せず）はポンプからの作動油により駆動される。Also, if the operating lever 13 is tilted by θ in the direction of the arrow shown in the figure,
The pipe line 10 and the pilot pipe line 22 communicate with each other, and the pilot pressure corresponding to the operating angle θ of the lever 13 is applied to the variable displacement pump 1.
act on the regulator 14 of the directional control valve 3 and the pilot chamber 15 of the directional control valve 3, switch the directional control valve 3 from position A to position B, increase the pump tilt angle, and actuate the actuator (
(not shown) is driven by hydraulic oil from a pump.
この状態において、管路２の油圧がパイロット管路１７
を経てレギュレータ１４に作用するので、第２図に示す
如き制御線図に沿った馬力制御がなされる。In this state, the hydraulic pressure in the pipe line 2 is
Since the power is applied to the regulator 14 through the above, horsepower control is performed according to a control diagram as shown in FIG.
ところが、負荷の増大によってリリーフ弁６が作動する
と、そのリリーフ量は、第５図に示す如く、馬力補償機
構を持った可変容量形ポンプ１ではＱ２、馬力補償機構
を持たないたとえば流量制御機構のみを有する可変容量
形ポンプではＱｌと、リリーフ量が犬となるために、燃
費、油温上昇等の点で太きむ問題を有していた。However, when the relief valve 6 is activated due to an increase in load, the relief amount is Q2 for the variable displacement pump 1 with a horsepower compensation mechanism, as shown in FIG. In a variable displacement pump having a variable displacement pump, the Ql and the amount of relief are close to each other, resulting in an increase in fuel consumption, oil temperature rise, etc.
本考案は前記するような点にかんがみ、ごく簡易な手段
でリリーフ弁作動時におけるポンプ吐出量を必要最少限
に留めることにより、前記の欠点を改善したものである
。In view of the above-mentioned points, the present invention has improved the above-mentioned drawbacks by keeping the pump discharge amount to the necessary minimum when the relief valve is activated using very simple means.
以下本考案の実施例を図面について説明する。Embodiments of the present invention will be described below with reference to the drawings.
第４図において、可変容量形ポンプ１とアクチュエータ
（図示せス）とを結ぶ管路２にはセンタバイパス型の方
向切換弁３，４．５を並設し、そのバイパス管路７およ
び戻り管路８はそれぞれタンク９に連通ずるとともに、
可変容量形ポンプ１と方向切換弁３間の管路２にポンプ
１の吐出圧を制限するリリーフ弁６を設け、このリリー
フ弁６の出口側と戻り管路８とを結ぶ逃し管路１９に低
圧リリーフ弁付き絞り２０を介装する。In FIG. 4, a center bypass type directional control valve 3, 4.5 is installed in parallel in a pipe line 2 connecting a variable displacement pump 1 and an actuator (not shown), and a bypass pipe line 7 and a return pipe are installed in parallel. The passages 8 each communicate with the tank 9, and
A relief valve 6 for limiting the discharge pressure of the pump 1 is provided in the pipe line 2 between the variable displacement pump 1 and the directional switching valve 3, and a relief pipe 19 connecting the outlet side of the relief valve 6 and the return pipe line 8 is provided. A throttle 20 with a low pressure relief valve is installed.
方向切換弁の数だげ並設されたリモコン弁１１は、操作
レバー１３とこの操作レバー１３により操作される可変
減圧弁１８．２１を有し、この可変減圧弁１８゜２１の
各入口ポートは管路１０でパイロット圧源である定容量
形ポンプ１２に、可変減圧弁１８゜２１０出ロポートは
パイロット管路２２．２３で方向切換弁のパイロット室
１５．１６に、各連結し、パイロット管路２２，２３の
各中間部は背向する一対のチェック弁２４．２５を介装
した管路２６で接続してこのチェック弁２４と２５の間
をオンオフ弁２７の如き流量制御弁を介装したパイロッ
ト管路２８で可変容量形ポンプ１のレギュレータ１４に
接続するとともに、オンオフ弁２７の設定圧力を導入圧
力で規制するパイロット室２９はパイロット管路３０で
低圧リリーフ弁付き絞り２０の上流側に接続しである。The remote control valves 11, which are arranged in parallel as many as the directional control valves, have an operating lever 13 and a variable pressure reducing valve 18, 21 operated by the operating lever 13, and each inlet port of the variable pressure reducing valve 18, 21 is The output ports of the variable pressure reducing valve 18 and 210 are connected to the constant displacement pump 12, which is a pilot pressure source, through the conduit 10, and to the pilot chambers 15 and 16 of the directional control valve through the pilot conduits 22 and 23, respectively. The intermediate portions of 22 and 23 are connected by a conduit 26 with a pair of check valves 24 and 25 facing opposite each other, and a flow rate control valve such as an on/off valve 27 is interposed between the check valves 24 and 25. A pilot chamber 29 is connected to the regulator 14 of the variable displacement pump 1 through a pilot line 28 and regulates the set pressure of the on-off valve 27 by the introduction pressure, and is connected to the upstream side of the throttle 20 with a low pressure relief valve through a pilot line 30. It is.
なお図中、３１はパイロット管路２８に接続する圧抜き
用絞り弁、３２は定容量形ポンプ１２用のリリーフ弁、
１７は管路２とレギュレータ１４とを結ぶパイロット管
路で可変容量形ポンプ１０馬力補償機能を確保する。In addition, in the figure, 31 is a pressure relief throttle valve connected to the pilot pipe 28, 32 is a relief valve for the constant displacement pump 12,
Reference numeral 17 is a pilot line connecting the line 2 and the regulator 14, and ensures a variable displacement pump 10 horsepower compensation function.
むおまた、前記リモコン弁１１は可変容量形ポンプ１お
よび方向切換弁を同時に制御するための一手段に過ぎず
、固より同様の機能を有するもので代替することは任意
である。Moreover, the remote control valve 11 is only one means for controlling the variable displacement pump 1 and the directional control valve at the same time, and it is optional to replace it with one having a similar function.
図において、リモコン弁１１の操作レバー１３を角度θ
だげ図示矢印方向に倒すと、可変減圧弁１８により管路
１０とパイロット管路２２が連通してパイロット管路２
２に角度θに応じたパイロット圧が発生し、このパイロ
ット圧が方向切換弁３のパイロット室１５と可変容量形
ポンプ１のレギュレータ１４にそれぞれ作用し、方向切
換弁３を位置Ａから位置Ｂに切換えるとともにポンプ傾
転角を増大させ、アクチュエータ（図示せず）はポンプ
からの作動油により駆動される。In the figure, the operating lever 13 of the remote control valve 11 is moved at an angle θ
When tilted in the direction of the arrow shown in the figure, the variable pressure reducing valve 18 connects the pipe line 10 and the pilot pipe line 22, and the pilot line 2
2, a pilot pressure corresponding to the angle θ is generated, and this pilot pressure acts on the pilot chamber 15 of the directional valve 3 and the regulator 14 of the variable displacement pump 1, and moves the directional valve 3 from position A to position B. At the same time as switching, the pump tilting angle is increased, and an actuator (not shown) is driven by hydraulic oil from the pump.
アンチ１エータの作動方向は操作レバー１３を倒す方向
で定まり、操作レバー１３の操作角度θに対応するリモ
コン弁１１からのパイロット圧Ｐｉ とポンプ１吐出量
Ｑとの関係は第３図に示す通りである。The operating direction of the anti-1 eater is determined by the direction in which the operating lever 13 is tilted, and the relationship between the pilot pressure Pi from the remote control valve 11 corresponding to the operating angle θ of the operating lever 13 and the pump 1 discharge amount Q is as shown in FIG. It is.
また、アクチュエータ作動時は、負荷圧がパイロット管
路１７を通ってレギュレータ１４に作用し、第２図に示
す如き制御線図に沿った馬力制御がなされる。Further, when the actuator is in operation, load pressure acts on the regulator 14 through the pilot pipe 17, and horsepower control is performed along a control diagram as shown in FIG.
アクチュエータ側の負荷が増大し、可変容量形ポンプ１
の吐出圧がリリーフ弁６の設定圧Ｋまで達すると、リリ
ーフ弁６は作動し、管路２の作動油の一部がリリーフ弁
６、低圧リリーフ弁付き絞り２０を通ってタンク９へ逃
げ、これにより低圧リリーフ弁付き絞り２０の上流側に
ここを通過する油量に応じた圧力を生じる。The load on the actuator side increases, and variable displacement pump 1
When the discharge pressure reaches the set pressure K of the relief valve 6, the relief valve 6 is activated, and a part of the hydraulic oil in the pipe line 2 escapes to the tank 9 through the relief valve 6 and the throttle 20 with a low pressure relief valve. As a result, a pressure is generated on the upstream side of the throttle 20 with a low pressure relief valve in accordance with the amount of oil passing therethrough.
この圧力がオンオフ弁２７のパイロット室２９に作用し
オンオフ弁の設定圧力を高めこの設定圧力がパイロット
管路２２の圧力以上になると、オンオフ弁２７のポペッ
トは閉じ、レギュレータ１４へのパイロット圧の供給が
断たれる。This pressure acts on the pilot chamber 29 of the on-off valve 27, increases the set pressure of the on-off valve, and when this set pressure exceeds the pressure of the pilot pipe 22, the poppet of the on-off valve 27 closes, and pilot pressure is supplied to the regulator 14. is cut off.
レギュレータ１４は、パイロット圧の供給が断たれかつ
圧抜き用絞り弁３１で圧抜きがなされることにより、ポ
ンプ吐出量を減じる。The regulator 14 reduces the pump discharge amount when the supply of pilot pressure is cut off and the pressure is relieved by the pressure relief throttle valve 31.
可変容量形ポンプ１の最少吐出量は、可変容量形ポンプ
１、アクチュエータ（図示せず）等の油もれおよびリリ
ーフ弁６のリリーフ量によっても必要とする回路の最高
圧を維持せしめ得る程度に設定されている。The minimum discharge amount of the variable displacement pump 1 is set to such an extent that the required maximum pressure of the circuit can be maintained even depending on oil leakage from the variable displacement pump 1, actuator (not shown), etc., and the relief amount of the relief valve 6. It is set.
アクチュエータ側の負荷の低減でリリーフ弁６のリリー
フ量が減少しこれにより低下したオンオフ弁２７の設定
圧力が管路２２の圧力より小さくなると、オンオフ弁２
７のポペットが開き、リモコン弁１１からのパイロット
圧をレギュレータ１４に導くのでポンプ吐出量が増大し
、通常作業に復帰することにたる。When the relief amount of the relief valve 6 decreases due to the reduction in the load on the actuator side, and the set pressure of the on-off valve 27, which has decreased as a result, becomes smaller than the pressure of the conduit 22, the on-off valve 2
The poppet 7 opens and guides the pilot pressure from the remote control valve 11 to the regulator 14, increasing the pump discharge amount and returning to normal operation.
即ち、本考案では、ＩＪ ＩＪ−フ弁６作動時のポンプ
吐出量は、必要とする回路の最高圧を維持せしめ得る程
度にまで減少するから、第５図に示す如く、最大圧力点
における所要リリーフ量が馬力補償機能を持たないもの
ではＱ□、馬力補償機能を持つものでもＱ２であるのに
対し、本考案の場合Ｑ３と格段に少なく、アクチュエー
タの力を減少させることなしに入力負荷を低減させるこ
とができる。That is, in the present invention, the pump discharge amount when the IJ valve 6 is operated is reduced to the extent that the required maximum pressure of the circuit can be maintained, so that the required amount at the maximum pressure point is reduced as shown in FIG. The amount of relief is Q□ in the model without a horsepower compensation function, and Q2 even in the model with a horsepower compensation function, but in the case of the present invention, it is much smaller at Q3, and the input load can be reduced without reducing the actuator force. can be reduced.
このことは、シリンダワークでピストンがシリンダエン
ドへ来た時の所要リリーフ量を比較した第６図について
もいえることである。This also applies to FIG. 6, which compares the amount of relief required when the piston reaches the cylinder end during cylinder work.
また、大きな慣性体の旋回加速時における所要リリーフ
量についてみると、第７図に示す如く、馬力補償機能を
持たないものでは、流量制御指令（最大傾転角指令）に
よる応答時間と旋回加速時間との差から生じる所要リリ
ーフ量がＪＡＢＣで示されるＱｃであり、馬力補償機構
を持つものでは、前記と同じ理由により馬力補償機構の
最高設定圧力時のポンプ吐出量に達する時間までの所要
リリーフ量がＪＡＤＥで示されるＱＢであるのに対し、
本考案ではＪＡＦＥで示されるＱＡであり、大幅に改善
されていることがわかる。In addition, looking at the amount of relief required during turning acceleration of a large inertial body, as shown in Figure 7, for a model without a horsepower compensation function, the response time and turning acceleration time due to the flow rate control command (maximum tilt angle command) The required relief amount resulting from the difference between the is the QB indicated by JADE, whereas
In the present invention, the QA is indicated by JAFE, and it can be seen that it has been significantly improved.
ここで、Ｆ点は可変容量形ポンプ１の最少流量点であり
、Ｆ点からＱＢの旋回加速線図との交点Ｅを結ぶ直線Ｆ
Ｅは、この可でリリーフ弁６を通過するリリーフ量が減
少して低圧リリーフ弁付き絞り２０の上流側圧力が減少
し、パイロット管路２２から２８への流入圧が漸増する
ことを示している。Here, point F is the minimum flow point of the variable displacement pump 1, and the straight line F connecting point F to the intersection E with the turning acceleration diagram of QB
E shows that in this case, the amount of relief passing through the relief valve 6 decreases, the upstream pressure of the throttle 20 with the low pressure relief valve decreases, and the inflow pressure from the pilot pipes 22 to 28 gradually increases. .
また、本考案ではリリーフ弁作動時のリリーフ量が少な
いために、リリーフ弁６は、過渡現象を考えなくても良
い程度に動的荷重がかからない場合、あるいは過渡現象
を考慮に入れても各油圧機器に支障のない程度にサージ
圧を抑制する特性をＩＪ ＩＪ−フ弁に持たせるならば
、非常に小さくてすむ。In addition, in the present invention, since the amount of relief when the relief valve is activated is small, the relief valve 6 can be used only when dynamic loads are not applied to the extent that there is no need to consider transient phenomena, or even when transient phenomena are taken into account, each hydraulic pressure is If the IJ valve has the characteristic of suppressing surge pressure to the extent that it does not affect the equipment, it can be made very small.
以上説明した如く本考案は、ごく筒易な手段でリリーフ
弁作動時の消費動力を節減し、かつリリーフ弁の小型化
をも図り得るものであるから、実施してその効果の大き
い考案である。As explained above, the present invention can reduce the power consumption when operating the relief valve by a very simple means, and can also reduce the size of the relief valve, so it is a device that will have great effects if implemented. .
第１図は従来装置の油圧系統図、第２図は馬力補償機構
のｐ−Ｑ線図、第３図は流量制御機構のｐｉ−Ｑ線図、
第４図は本考案の一実施例を示す油圧系統図、第５図は
最高圧力点における所要リリーフ量の比較図、第６図は
シリンダワークでリリーフ弁が作動した時の作動時間と
リリーフ油量との関係を示す図、第７図は大きな慣性体
の旋回加速時における所要リリーフ量の比較図である。
１・・・・・・可変容量形ポンプ、３，４．５・・・・
・・方向切換弁、６・・・・・・リリーフ弁、１１・・
・・・・リモコン弁、１２・・・・・・定容量形ポンプ
、１３・・・・・・操作レバー、１４・・・・・・レギ
ュレータ、１８．２１・・・・・・可変減圧弁、２０・
・・・・・低圧リリーフ弁付き絞り、２７・・・・・・
オンオフ弁、２９・・・・・・パイロット室、３１・・
・・・・圧抜き用絞り弁。Figure 1 is a hydraulic system diagram of the conventional device, Figure 2 is a p-Q diagram of the horsepower compensation mechanism, Figure 3 is a pi-Q diagram of the flow rate control mechanism,
Figure 4 is a hydraulic system diagram showing an embodiment of the present invention, Figure 5 is a comparison diagram of the required relief amount at the highest pressure point, and Figure 6 is the operating time and relief oil when the relief valve is operated during cylinder work. FIG. 7 is a comparison diagram of the required relief amount when a large inertial body is accelerated in rotation. 1... Variable displacement pump, 3, 4.5...
...Directional switching valve, 6...Relief valve, 11...
...Remote control valve, 12...Fixed displacement pump, 13...Operation lever, 14...Regulator, 18.21...Variable pressure reducing valve , 20・
... Throttle with low pressure relief valve, 27...
On-off valve, 29... Pilot room, 31...
... Throttle valve for pressure relief.
Claims (1)
プ吐出圧を制限するリリーフ弁および方向切換弁を各配
設し、前記可変容量形ポンプのレギュレータにはパイロ
ット圧源からのパイロット圧を流量制御弁を介して導く
ようにするとともに、前記リリーフ弁の下流側に低圧リ
リーフ弁付き絞りを設け、この低圧リリーフ弁付き絞り
の上流側と前記流量制御弁の設定圧力を導入圧力で規制
するパイロット室とを管路で接続するようにしたことを
特徴とする可変容量形ポンプの自動負荷軽減装置。A relief valve and a directional control valve that limit the pump discharge pressure are installed in the pipeline connecting the variable displacement pump and the actuator, and the regulator of the variable displacement pump is connected to a flow control valve that controls the pilot pressure from the pilot pressure source. A throttle with a low pressure relief valve is provided on the downstream side of the relief valve, and a pilot chamber and a pilot chamber are provided on the upstream side of the throttle with a low pressure relief valve and the set pressure of the flow rate control valve is regulated by the introduction pressure. An automatic load reduction device for a variable displacement pump, characterized in that the two are connected by a conduit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10635574U JPS5830152Y2 (en) | 1974-09-03 | 1974-09-03 | How to use the pump |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10635574U JPS5830152Y2 (en) | 1974-09-03 | 1974-09-03 | How to use the pump |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5133202U JPS5133202U (en) | 1976-03-11 |
| JPS5830152Y2 true JPS5830152Y2 (en) | 1983-07-02 |
Family
ID=28322199
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10635574U Expired JPS5830152Y2 (en) | 1974-09-03 | 1974-09-03 | How to use the pump |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5830152Y2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5519904A (en) * | 1978-07-27 | 1980-02-13 | Sumitomo Heavy Ind Ltd | Discharge flow control equipment of variable capacity pump |
| JPS56139316A (en) * | 1980-01-07 | 1981-10-30 | Komatsu Ltd | Power loss reduction controller for oil-pressure type construction machine |
-
1974
- 1974-09-03 JP JP10635574U patent/JPS5830152Y2/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5133202U (en) | 1976-03-11 |
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