JPH05172111A - Variable hydraulic pump capacity control device for pressure-compensating hydraulic circuit - Google Patents
Variable hydraulic pump capacity control device for pressure-compensating hydraulic circuitInfo
- Publication number
- JPH05172111A JPH05172111A JP35565291A JP35565291A JPH05172111A JP H05172111 A JPH05172111 A JP H05172111A JP 35565291 A JP35565291 A JP 35565291A JP 35565291 A JP35565291 A JP 35565291A JP H05172111 A JPH05172111 A JP H05172111A
- Authority
- JP
- Japan
- Prior art keywords
- pressure
- pump
- delivery pressure
- pump discharge
- 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
Links
Landscapes
- Operation Control Of Excavators (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、パワーショベル等に用
いられる１つの可変油圧ポンプの吐出圧油を複数の油圧
アクチュエータに供給する圧力補償式油圧回路における
可変油圧ポンプの容量を制御する装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for controlling the capacity of a variable hydraulic pump in a pressure compensating hydraulic circuit for supplying the discharge pressure oil of one variable hydraulic pump used for a power shovel or the like to a plurality of hydraulic actuators. ..
【０００２】[0002]
【従来の技術】１つの可変油圧ポンプの吐出圧油を複数
の油圧アクチュエータに供給するには、可変油圧ポンプ
の吐出路に複数の操作弁を設け、その操作弁を切換える
ことで各油圧アクチュエータに圧油を供給すれば良い
が、このようにすると複数の油圧アクチュエータに圧油
を同時に供給する際に、負荷の小さな油圧アクチュエー
タにのみ圧油が供給されて負荷の大きな油圧アクチュエ
ータに圧油が供給されなくなってしまう。このことで解
消する圧力補償式油圧回路として、例えば特公平２−４
９４０５号公報に示すものが提案されている。2. Description of the Related Art In order to supply the discharge pressure oil of one variable hydraulic pump to a plurality of hydraulic actuators, a plurality of operation valves are provided in the discharge passage of the variable hydraulic pump, and the operation valves are switched so that each hydraulic actuator can be operated. Although it is sufficient to supply pressure oil, when supplying pressure oil to multiple hydraulic actuators at the same time, pressure oil is supplied only to the hydraulic actuator with a small load and pressure oil is supplied to the hydraulic actuator with a large load. It will not be done. As a pressure-compensating hydraulic circuit that is solved by this, for example, Japanese Patent Publication No. 2-4
The one shown in Japanese Patent No. 9405 has been proposed.
【０００３】かかる圧力補償式油圧回路を模式的に示す
と図１に示すようになる。つまり、可変油圧ポンプ１の
吐出路１ａに複数の操作弁２を設け、各操作弁２と各油
圧アクチュエータ３を接続する回路４に圧力補償弁５を
それぞれ設けると共に、各回路４の圧力、つまり負荷圧
における最も高い圧力をチェック弁６で負荷圧検出路７
に検出し、その検出した負荷圧を各圧力補償弁５の受圧
部５ａに作用してその負荷圧に見合う圧力にセットし、
各操作弁２の出口側圧力を等しくして各操作弁２を同時
操作した時に各操作弁の開口面積に比例した分流比で各
油圧アクチュエータ３に圧油を供給できるようにしてあ
る。The pressure-compensated hydraulic circuit is schematically shown in FIG. That is, a plurality of operating valves 2 are provided in the discharge passage 1a of the variable hydraulic pump 1, a pressure compensating valve 5 is provided in each of the circuits 4 that connect each operating valve 2 and each hydraulic actuator 3, and the pressure of each circuit 4, that is, The highest pressure in the load pressure is detected by the check valve 6 in the load pressure detection path 7
Detected, and the detected load pressure is applied to the pressure receiving portion 5a of each pressure compensation valve 5 to set the pressure corresponding to the load pressure.
When the outlet side pressures of the respective operation valves 2 are made equal and the respective operation valves 2 are simultaneously operated, the pressure oil can be supplied to the respective hydraulic actuators 3 at a diversion ratio proportional to the opening area of each operation valve.
【０００４】かかる圧力補償式油圧回路であると、圧力
補償弁５の機能によって各油圧アクチュエータ３の負荷
の大小に無関係に操作弁２の開口面積に比例した流量分
配ができるから、１つの可変油圧ポンプ１の吐出圧油を
操作弁２の操作量に比例して各油圧アクチュエータ３に
それぞれ供給できる。また負荷圧によって流量制御特性
が変化しないという特性がある。With such a pressure-compensating hydraulic circuit, the function of the pressure-compensating valve 5 allows the flow rate distribution to be proportional to the opening area of the operation valve 2 regardless of the load on each hydraulic actuator 3, so that one variable hydraulic pressure is used. The discharge pressure oil of the pump 1 can be supplied to each hydraulic actuator 3 in proportion to the operation amount of the operation valve 2. Further, there is a characteristic that the flow rate control characteristic does not change depending on the load pressure.
【０００５】前述の可変油圧ポンプ１の容量、つまり１
回転当り吐出流量は図１に示すように検出した負荷圧と
ポンプ吐出圧をポンプサーボバルブ８に供給して負荷圧
よりもポンプ吐出圧が設定差圧だけ高くなるように制御
している。The capacity of the variable hydraulic pump 1 described above, that is, 1
As shown in FIG. 1, the discharge flow rate per rotation is controlled by supplying the detected load pressure and pump discharge pressure to the pump servo valve 8 so that the pump discharge pressure becomes higher than the load pressure by a set differential pressure.
【０００６】前述のように可変油圧ポンプ１は負荷圧変
動に応じてポンプ吐出圧が設定差圧を維持する様に作動
するから、慣性体の駆動時には負荷圧が急激に上昇する
とポンプ吐出圧は高い圧力に急激に上昇してしまいショ
ックを生ずる。As described above, the variable hydraulic pump 1 operates so that the pump discharge pressure maintains a set differential pressure according to the load pressure fluctuation. Therefore, when the inertial body is driven, the pump discharge pressure increases when the load pressure sharply increases. It suddenly rises to a high pressure and causes a shock.
【０００７】このために、ポンプサーボバルブ８の制御
スプールにおける負荷圧受圧部とポンプ吐出圧受圧部に
受圧面積差を設け、ポンプ吐出圧が高くなると設定差圧
を低くしてポンプ吐出圧が急激に上昇しないようにして
いる例がある。For this reason, a pressure receiving area difference is provided between the load pressure receiving portion and the pump discharge pressure receiving portion in the control spool of the pump servo valve 8, and when the pump discharge pressure becomes high, the set differential pressure becomes low and the pump discharge pressure becomes sharp. There is an example that does not rise to.
【０００８】[0008]
【発明が解決しようとする課題】前述のようにポンプ吐
出圧と負荷圧の設定差圧をポンプ吐出圧によってコント
ロールすると、ポンプ吐出圧の低圧から高圧の全域にお
いて前記設定差圧が変化するから前述の圧力補償式油圧
回路における負荷圧によって流量制御特性が変化しない
利点が損なわれる。なぜなら、圧力補償弁５はポンプ吐
出圧と負荷圧の差圧によって開度が制御されて通過流量
が変化するので、前述のようにポンプ吐出圧と負荷圧の
設定差圧が異なると同じ負荷圧でも圧力補償弁の開度が
変化して通過流量が変化するために操作弁の開度が同じ
でも流量が異なって流量制御特性が変化してしまう。If the set differential pressure between the pump discharge pressure and the load pressure is controlled by the pump discharge pressure as described above, the set differential pressure changes in the entire range from the low pump discharge pressure to the high pump discharge pressure. The advantage that the flow control characteristic does not change due to the load pressure in the pressure-compensated hydraulic circuit is deteriorated. This is because the opening of the pressure compensating valve 5 is controlled by the pressure difference between the pump discharge pressure and the load pressure, and the passing flow rate changes. Therefore, if the set pressure difference between the pump discharge pressure and the load pressure is different, the same load pressure is applied as described above. However, since the opening degree of the pressure compensating valve changes and the passing flow rate changes, even if the opening degree of the operation valve is the same, the flow rate is different and the flow rate control characteristic changes.
【０００９】そこで、本発明は前述の課題を解決できる
ようにした圧力補償式油圧回路の可変油圧ポンプ容量制
御装置を提供することを目的とする。SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a variable hydraulic pump displacement control device for a pressure-compensated hydraulic circuit, which can solve the above-mentioned problems.
【００１０】[0010]
【課題を解決するための手段】圧力補償式油圧回路の可
変油圧ポンプ１の容量を制御するシリンダ１１と、この
シリンダ１１にポンプ吐出圧を供給する制御弁１４と、
ポンプ吐出圧を検出するセンサー２０と、コントローラ
１９を設け、前記制御弁１４を負荷圧によって容量増方
向に押され、ポンプ吐出圧とソレノイド１８の推力で容
量減方向に押されるものとし、前記コントローラ１９は
ポンプ吐出圧の変化率が大きい時にソレノイド１８へ通
電制御するものとした圧力補償式油圧回路の可変油圧ポ
ンプ容量制御装置。A cylinder 11 for controlling the capacity of a variable hydraulic pump 1 of a pressure compensating hydraulic circuit, and a control valve 14 for supplying pump discharge pressure to the cylinder 11.
A sensor 20 for detecting the pump discharge pressure and a controller 19 are provided, and the control valve 14 is pushed in the capacity increasing direction by the load pressure, and is pushed by the pump discharge pressure and the thrust of the solenoid 18 in the capacity decreasing direction. Reference numeral 19 is a variable hydraulic pump displacement control device of a pressure compensating hydraulic circuit which controls energization of the solenoid 18 when the rate of change of pump discharge pressure is large.
【００１１】ポンプ吐出圧の変化率が大きい時にソレノ
イド１８へ通電して推力を変化させることでポンプ吐出
圧と負荷圧の設定差圧を変化させるから、ポンプ吐出圧
が急激に上昇することがないし、ポンプ吐出圧の変化率
が小さい時には前記設定差圧が変化せずに流量制御特性
が変化しない。When the rate of change of the pump discharge pressure is large, the solenoid 18 is energized to change the thrust to change the set differential pressure between the pump discharge pressure and the load pressure, so that the pump discharge pressure does not rise sharply. When the rate of change of the pump discharge pressure is small, the set differential pressure does not change and the flow rate control characteristic does not change.
【００１２】[0012]
【実 施 例】図２に示すように、可変油圧ポンプ１の
斜板１０はシリンダ１１で傾転され、そのシリンダ１１
の小径受圧室１２は吐出路１ａに接続し、大径受圧室１
３は制御弁１４で吐出路１ａとタンク１５に接続され
る。前記制御弁１４は第１受圧部１６に作用する負荷圧
でドレーン位置Ａに押され、第２受圧部１７に作用する
ポンプ吐出圧とソレノイド１８の推力で供給位置Ｂに押
され、そのソレノイド１８にはコントローラ１９で通電
制御されると共に、コントローラ１９には圧力センサ２
０でポンプ吐出圧が入力され、そのポンプ吐出圧の変化
によってソレノイド１８へ通電制御する。[Example] As shown in FIG. 2, the swash plate 10 of the variable hydraulic pump 1 is tilted by a cylinder 11, and the cylinder 11 is tilted.
The small diameter pressure receiving chamber 12 is connected to the discharge passage 1a, and the large diameter pressure receiving chamber 1
A control valve 14 is connected to the discharge passage 1a and the tank 15. The control valve 14 is pushed to the drain position A by the load pressure acting on the first pressure receiving portion 16, and is pushed to the supply position B by the pump discharge pressure acting on the second pressure receiving portion 17 and the thrust of the solenoid 18, and the solenoid 18 Is energized by the controller 19, and the pressure sensor 2 is attached to the controller 19.
When the pump discharge pressure is 0, the solenoid 18 is energized and controlled by the change in the pump discharge pressure.
【００１３】次に作動を説明する。ソレノイド１８の推
力を考えなければポンプ吐出圧が高くなると制御弁１４
が供給位置Ｂとなってシリンダ１１の大径受圧室１３に
供給されて伸長するから斜板１０を容量小方向に傾転
し、負荷圧が高くなると制御弁１４はドレーン位置Ａと
なってシリンダ１１の大径受圧室１３がタンク１５に接
続して縮少するから斜板１０を容量大方向に傾転する。
可変油圧ポンプ１の容量が減少するとポンプ吐出圧が低
圧となり、増大するとポンプ吐出圧が高圧となるので、
ソレノイド１８の推力を考えなければ制御弁１４で可変
油圧ポンプへの容量がポンプ吐出圧と負荷圧の差圧が設
定差圧となるように制御される。ソレノイド１８の推力
が作用すると制御弁１４が供給位置Ａとなって前述のよ
うに可変油圧ポンプ１の容量が減少するから、ソレノイ
ド１８の推力に比例してポンプ吐出圧と負荷圧の設定差
圧が低くなる。前記コントローラ１９は入力されたポン
プ吐出圧に基づいて単位時間当りの圧力変化、すなわち
変化率を演算し、その変化率がある値以上の時には変化
率に比例して図３のようにソレノイド１８に通電してソ
レノイド１８の推力を大きくする。これにより、図４に
示すようにポンプ吐出圧と負荷圧の設定差圧がある値の
変化率以上の時にその変化率に比例して小さくなるの
で、ポンプ吐出圧の圧力変化が緩かになって急激に圧力
上昇しないし、ポンプ吐出圧の変化率がある値以内の時
にはポンプ吐出圧と負荷圧の設低差圧が一定となって流
量制御特性が変化しない。Next, the operation will be described. Unless the thrust of the solenoid 18 is taken into consideration, if the pump discharge pressure becomes high, the control valve 14
Is supplied to the large-diameter pressure receiving chamber 13 of the cylinder 11 and expands, so that the swash plate 10 is tilted in the small capacity direction, and when the load pressure becomes high, the control valve 14 becomes the drain position A and becomes the cylinder. Since the large-diameter pressure receiving chamber 13 of 11 is connected to the tank 15 and contracts, the swash plate 10 is tilted in the direction of large capacity.
When the displacement of the variable hydraulic pump 1 decreases, the pump discharge pressure becomes low, and when it increases, the pump discharge pressure becomes high.
If the thrust of the solenoid 18 is not taken into consideration, the control valve 14 controls the displacement of the variable hydraulic pump so that the differential pressure between the pump discharge pressure and the load pressure becomes a set differential pressure. When the thrust of the solenoid 18 acts, the control valve 14 moves to the supply position A, and the capacity of the variable hydraulic pump 1 decreases as described above. Will be lower. The controller 19 calculates a pressure change per unit time, that is, a change rate based on the input pump discharge pressure, and when the change rate is equal to or more than a certain value, the solenoid 18 is proportional to the change rate as shown in FIG. Energize to increase the thrust of the solenoid 18. As a result, as shown in FIG. 4, when the set differential pressure between the pump discharge pressure and the load pressure is greater than or equal to the rate of change of a certain value, it decreases in proportion to the rate of change, so the pressure change of the pump discharge pressure becomes gentle. Therefore, the pressure does not rise sharply, and when the rate of change of the pump discharge pressure is within a certain value, the set differential pressure between the pump discharge pressure and the load pressure becomes constant, and the flow rate control characteristic does not change.
【００１４】[0014]
【発明の効果】ポンプ吐出圧の変化率が大きい時にソレ
ノイド１８に通電して推力を変化させることでポンプ吐
出圧と負荷圧の設定差圧を変化するから、ポンプ吐出圧
が急激に上昇することがないし、ポンプ吐出圧の変化率
が小さい時には前記設定差圧が変化せずに流量制御特性
が変化しない。When the rate of change in pump discharge pressure is large, the set differential pressure between the pump discharge pressure and the load pressure is changed by energizing the solenoid 18 to change the thrust, so that the pump discharge pressure rises rapidly. When the rate of change in pump discharge pressure is small, the set differential pressure does not change and the flow rate control characteristic does not change.
【図１】従来の油圧回路図である。FIG. 1 is a conventional hydraulic circuit diagram.
【図２】本発明の実施例を示す線図的構成説明図であ
る。FIG. 2 is a diagrammatic configuration explanatory view showing an embodiment of the present invention.
【図３】ソレノイド通電量を示す図表である。FIG. 3 is a chart showing a solenoid energization amount.
【図４】設定差圧を示す図表である。FIG. 4 is a chart showing set differential pressures.
１…可変油圧ポンプ、１ａ…吐出路、２…操作弁、３…
油圧アクチュエータ、４…回路、５…圧力補償弁、７…
負荷圧検出路、１１…シリンダ、１２…小径受圧室、１
３…大径受圧室、１４…制御弁、１９…コントローラ、
２０…圧力センサ。1 ... Variable hydraulic pump, 1a ... Discharge passage, 2 ... Operation valve, 3 ...
Hydraulic actuator, 4 ... Circuit, 5 ... Pressure compensation valve, 7 ...
Load pressure detection path, 11 ... Cylinder, 12 ... Small diameter pressure receiving chamber, 1
3 ... Large diameter pressure receiving chamber, 14 ... Control valve, 19 ... Controller,
20 ... Pressure sensor.
Claims (1)
操作弁２を設け、各操作弁２と油圧アクチュエータ３を
接続する回路４に圧力補償弁５をそれぞれ設け、前記各
油圧アクチュエータ３の負荷圧の最高圧を検出する負荷
圧検出路７を前記各圧力補償弁５の受圧部５ａに接続し
た圧力補償式油圧回路において、 前記可変油圧ポンプ１の容量を制御するシリンダ１１
と、このシリンダ１１にポンプ吐出圧を供給する制御弁
１４と、ポンプ吐出圧を検出するセンサー２０と、コン
トローラ１９を設け、前記制御弁１４を負荷圧によって
容量増方向に押され、ポンプ吐出圧とソレノイド１８の
推力で容量減方向に押されるものとし、前記コントロー
ラ１９はポンプ吐出圧の変化率が大きい時にソレノイド
１８へ通電制御するものとした圧力補償式油圧回路の可
変油圧ポンプ容量制御装置。1. A plurality of operating valves 2 are provided in a discharge passage 1a of a variable hydraulic pump 1, a pressure compensating valve 5 is provided in a circuit 4 connecting each operating valve 2 and a hydraulic actuator 3, and each hydraulic actuator 3 is provided with a pressure compensating valve 5. In a pressure compensating hydraulic circuit in which a load pressure detecting path 7 for detecting the maximum load pressure is connected to the pressure receiving portion 5a of each pressure compensating valve 5, a cylinder 11 for controlling the capacity of the variable hydraulic pump 1 is provided.
A control valve 14 for supplying the pump discharge pressure to the cylinder 11, a sensor 20 for detecting the pump discharge pressure, and a controller 19 are provided, and the control valve 14 is pushed in the capacity increasing direction by the load pressure, And the thrust of the solenoid 18 is pushed in the direction of decreasing the displacement, and the controller 19 controls the energization of the solenoid 18 when the rate of change of the pump discharge pressure is large.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP35565291A JPH05172111A (en) | 1991-12-24 | 1991-12-24 | Variable hydraulic pump capacity control device for pressure-compensating hydraulic circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP35565291A JPH05172111A (en) | 1991-12-24 | 1991-12-24 | Variable hydraulic pump capacity control device for pressure-compensating hydraulic circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH05172111A true JPH05172111A (en) | 1993-07-09 |
Family
ID=18445074
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP35565291A Pending JPH05172111A (en) | 1991-12-24 | 1991-12-24 | Variable hydraulic pump capacity control device for pressure-compensating hydraulic circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH05172111A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH10281102A (en) * | 1997-04-11 | 1998-10-20 | Komatsu Ltd | Capacity control device for variable capacity type hydraulic pump |
| CN102269157A (en) * | 2011-06-08 | 2011-12-07 | 长沙中联重工科技发展股份有限公司 | Pressure regulating method and system for concrete pumping apparatus, and concrete pumping apparatus |
| JP2018091198A (en) * | 2016-12-01 | 2018-06-14 | トヨタ自動車株式会社 | Oil supply device of on-vehicle engine |
-
1991
- 1991-12-24 JP JP35565291A patent/JPH05172111A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH10281102A (en) * | 1997-04-11 | 1998-10-20 | Komatsu Ltd | Capacity control device for variable capacity type hydraulic pump |
| CN102269157A (en) * | 2011-06-08 | 2011-12-07 | 长沙中联重工科技发展股份有限公司 | Pressure regulating method and system for concrete pumping apparatus, and concrete pumping apparatus |
| JP2018091198A (en) * | 2016-12-01 | 2018-06-14 | トヨタ自動車株式会社 | Oil supply device of on-vehicle engine |
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