JP2010230062A - Oil pressure supply device - Google Patents

Oil pressure supply device Download PDF

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JP2010230062A
JP2010230062A JP2009076869A JP2009076869A JP2010230062A JP 2010230062 A JP2010230062 A JP 2010230062A JP 2009076869 A JP2009076869 A JP 2009076869A JP 2009076869 A JP2009076869 A JP 2009076869A JP 2010230062 A JP2010230062 A JP 2010230062A
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oil passage
flow rate
supply device
displacement pump
variable displacement
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Hisao Takami
久夫 高見
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Kayaba System Machinery Co Ltd
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Kayaba System Machinery Co Ltd
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Abstract

<P>PROBLEM TO BE SOLVED: To provide an oil pressure supply device capable of performing control superior in energy efficiency by only a hydraulic circuit. <P>SOLUTION: This oil pressure supply device includes a variable capacity pump 3 having a tilting cylinder 2 for controlling a tilting angle, an oil passage 7 connected from the variable capacity pump 3 to an actuator, an accumulator 6 connected to a middle of the oil passage 7, and a return oil passage 12 branched from the middle of the oil passage 7 for returning surplus flow rate from the variable capacity pump 3 via a relief valve 8 to a tank T. A throttle 10 is provided in the middle of the return oil passage 12, and a differential pressure valve 11 is provided for operating the tilting cylinder 2 so that, when differential pressure between front and rear of the throttle 10 becomes larger than a set value, the discharge flow rate of the variable capacity pump 3 is decreased and the differential pressure is returned to the set value. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

本発明は、例えば、シミュレータ等の試験装置に使用する油圧源としての油圧供給装置に関する。   The present invention relates to a hydraulic pressure supply device as a hydraulic pressure source used in a test apparatus such as a simulator.

従来より、この種の油圧供給装置の一例として、図２に示すものを例示することができる。   Conventionally, as an example of this type of hydraulic pressure supply apparatus, the one shown in FIG. 2 can be exemplified.

この油圧供給装置は、サーボ弁（図示なし）を使用することで、圧力一定の油圧源が要求される油圧回路であって、電動モータ２０によって駆動される固定容量ポンプ２１から吐出される作動油は、チェック弁２３を備えた吐出通路２２を通って上記サーボ弁へと導かれる。   This hydraulic pressure supply device is a hydraulic circuit that requires a hydraulic pressure source having a constant pressure by using a servo valve (not shown), and is hydraulic oil discharged from a fixed displacement pump 21 driven by an electric motor 20. Is guided to the servo valve through a discharge passage 22 having a check valve 23.

また、固定容量ポンプ２１からの余剰流量は、リリーフ弁２４を介してサーボ弁からの戻り通路２５に流れると共に、タンクＴに戻される。   Further, the excess flow rate from the fixed capacity pump 21 flows into the return passage 25 from the servo valve via the relief valve 24 and is returned to the tank T.

なお、上記吐出通路２２にはアキュムレータ２６が設けられており、サーボ弁が高速作動する際の流量変化に充分対応できるようになっている。   The discharge passage 22 is provided with an accumulator 26, which can sufficiently cope with a change in flow rate when the servo valve operates at high speed.

上記の油圧供給装置においては、サーボ弁で消費される流量に関係なく、上記固定容量ポンプ２１が常に固定流量を吐出するので、常にこの固定流量と圧力を掛け合わせた動力を要する。   In the above hydraulic pressure supply device, the fixed displacement pump 21 always discharges a fixed flow rate regardless of the flow rate consumed by the servo valve. Therefore, a power obtained by multiplying the fixed flow rate and the pressure is always required.

したがって、この構成の油圧供給装置では、サーボ弁で消費される流量に関係なく上記した動力を常に要することになって、非常にエネルギー効率が悪いという問題点がある。   Therefore, the hydraulic pressure supply device having this configuration always requires the above-described power regardless of the flow rate consumed by the servo valve, and has a problem that it is very inefficient in energy.

そこでこのような不具合を解決する従来の油圧供給装置に関する先行技術文献を調査し、特許庁ホームページで公報を検索したが、発見することはできなかった。   Therefore, prior art documents relating to conventional hydraulic pressure supply devices that solve such problems were investigated, and gazettes were searched on the JPO homepage, but they could not be found.

そこで、本発明者は上記の不具合を解決する技術を研究し、本発明を完成した。   Therefore, the present inventor researched a technique for solving the above-mentioned problems and completed the present invention.

即ち、本発明の目的は、エネルギー効率の良い制御を油圧回路のみで行うことができる油圧供給装置を提供することである。   That is, an object of the present invention is to provide a hydraulic pressure supply device capable of performing energy efficient control only by a hydraulic circuit.

上記の目的を達成するため、本発明の油圧供給装置は、傾転角を制御するための傾転シリンダを備えた可変容量ポンプと、この可変容量ポンプからアクチュエータに接続される油路と、この油路の途中に接続されたアキムレータと、上記油路の途中から分岐して可変容量ポンプからの余剰流量をリリーフ弁を介してタンクに戻す戻し油路とを供えた油圧供給装置であって、上記戻し油路の途中に絞りを設けると共に、この絞りの前後の差圧が設定値より大きくなると可変容量ポンプの吐出流量を減らして上記設定値に戻すよう上記傾転シリンダを作動させる差圧弁を設けている。   In order to achieve the above object, a hydraulic pressure supply device according to the present invention includes a variable displacement pump having a tilt cylinder for controlling a tilt angle, an oil passage connected from the variable displacement pump to an actuator, A hydraulic supply device provided with an accumulator connected in the middle of the oil passage, and a return oil passage that branches off from the middle of the oil passage and returns the excess flow rate from the variable displacement pump to the tank via the relief valve, A throttle is provided in the middle of the return oil passage, and when the differential pressure before and after the throttle becomes larger than a set value, a differential pressure valve that operates the tilt cylinder to reduce the discharge flow rate of the variable displacement pump and return to the set value. Provided.

本発明によれば、戻り油路に絞りを設けると共に、この絞りの前後の差圧で切り換わる差圧弁の作動油を用いて傾転シリンダを作動させるようにしたので、例えばアクチュエータとしてのサーボ弁への負荷流量が小さい場合には、傾転シリンダの傾転角を小さくして可変容量ポンプの吐出流量を下げると共に、アクチュエータへの負荷流量が大きくなると、傾転シリンダの傾転角を大きくして可変容量ポンプの吐出流量を上げるで、常に余剰流量を小流量で一定としたポンプ吐出制御ができて油圧源として大変効率が良い。   According to the present invention, a throttle is provided in the return oil passage, and the tilting cylinder is operated using the hydraulic oil of the differential pressure valve that is switched by the differential pressure before and after the throttle. For example, a servo valve as an actuator When the load flow rate to the actuator is small, the tilt angle of the tilt cylinder is reduced to lower the discharge flow rate of the variable displacement pump, and when the load flow rate to the actuator is increased, the tilt angle of the tilt cylinder is increased. By increasing the discharge flow rate of the variable displacement pump, it is possible to control the pump discharge so that the surplus flow rate is always constant at a small flow rate, which is very efficient as a hydraulic source.

また、リリーフ弁圧力に絞りの差圧を加えた圧力が一定圧力となるので、例えば、アクチュエータとしてサーボ弁を使用する環境設定が可能となる。   Further, since the pressure obtained by adding the differential pressure of the throttle to the relief valve pressure becomes a constant pressure, for example, it is possible to set an environment in which a servo valve is used as an actuator.

さらには、油路の途中にアキュムレータを設けたので、可変容量ポンプから吐出する作動油の一部を常に蓄えることで、上記絞りと相俟って、例えば、アクチュエータが高速のサーボ弁である場合のように、高速で要求される流量変化にも充分に対応することができる。   Furthermore, since an accumulator is provided in the middle of the oil passage, by storing a part of the hydraulic oil discharged from the variable displacement pump at all times, for example, when the actuator is a high-speed servo valve in combination with the throttle As described above, it is possible to sufficiently cope with a flow rate change required at a high speed.

本発明の実施の形態を示す油圧供給装置の油圧回路図である。1 is a hydraulic circuit diagram of a hydraulic pressure supply device showing an embodiment of the present invention. 従来例を示す油圧供給装置の油圧回路図である。It is a hydraulic circuit diagram of a hydraulic pressure supply device showing a conventional example.

以下に、本発明の油圧供給装置を、サーボ弁を使用した加振機の油圧源に具体化した形態を図に基づいて説明する。   Hereinafter, an embodiment in which the hydraulic pressure supply device of the present invention is embodied as a hydraulic power source of a vibration exciter using a servo valve will be described with reference to the drawings.

図１に示すように、電動機１により回転駆動されると共に、ポンプの傾転角を制御するための傾転シリンダ２を備えた可変容量ポンプ３と、この可変容量ポンプ３を上記サーボ弁に接続する油路７と、この油路７の途中に接続されたアキムレータ６と、上記油路７の途中から分岐して可変容量ポンプ３からの余剰流量をリリーフ弁８を介してタンクＴに戻す戻し油路１２とを供えた油圧供給装置であって、上記戻し油路１２の途中に絞り１０を設けると共に、この絞り１０の前後の差圧が設定値より大きくなると可変容量ポンプ３の吐出流量を減らして上記設定値に戻すよう上記傾転シリンダ２を作動させる差圧弁１１を設けている。   As shown in FIG. 1, a variable displacement pump 3 that is rotationally driven by an electric motor 1 and includes a tilt cylinder 2 for controlling the tilt angle of the pump, and this variable displacement pump 3 is connected to the servo valve. And the accumulator 6 connected in the middle of the oil path 7 and returning from the variable capacity pump 3 to the tank T via the relief valve 8 by branching from the middle of the oil path 7. A hydraulic pressure supply device provided with an oil passage 12, wherein a throttle 10 is provided in the middle of the return oil passage 12, and when the differential pressure before and after the throttle 10 becomes larger than a set value, the discharge flow rate of the variable displacement pump 3 is reduced. A differential pressure valve 11 for operating the tilting cylinder 2 is provided so as to reduce it to the set value.

この油圧供給装置は、サーボ弁を使用することで、圧力一定の油圧源が要求される油圧回路であって、可変容量ポンプ３から吐出される作動油は、チェック弁１３を備えた通路１２を通って上記サーボ弁へと導かれる。   This hydraulic pressure supply device is a hydraulic circuit that requires a hydraulic pressure source with a constant pressure by using a servo valve. The hydraulic oil discharged from the variable displacement pump 3 passes through a passage 12 having a check valve 13. Through to the servo valve.

以下、さらに詳述すると、上記傾転シリンダ２はそのピストンロッド２ａの伸縮動作によって可変容量ポンプ３の傾転角を変えて吐出流量を制御するようになっており、ピストン側室２ｂには上記差圧弁１１からの作動油が供給されると共に、ロッド側室にはコイルスプリング２ｄが配置されている。   More specifically, the tilt cylinder 2 controls the discharge flow rate by changing the tilt angle of the variable displacement pump 3 by the expansion and contraction operation of the piston rod 2a. The hydraulic oil from the pressure valve 11 is supplied, and a coil spring 2d is disposed in the rod side chamber.

上記コイルスプリング２ｄは上記ピストン側室２ｂに作動油が供給されていない状態では、その附勢力によって可変容量ポンプ３の吐出量が、最大値となるよう設定されている。   The coil spring 2d is set so that the discharge amount of the variable displacement pump 3 is maximized by the urging force when the hydraulic oil is not supplied to the piston side chamber 2b.

差圧弁１１はスプリング１１ａにより図１に示す初期状態に配置される３ポート２位置切換弁であって、絞り１０前後の差圧が上記設定値を超えるとスプリング１１ａの弾性力に抗して切り換り、絞り１０上流側の作動油を傾転シリンダ２の上記ピストン側室２ｂに導き、上記コイルスプリング２ｄの附勢力に抗してピストンロッド２ａを伸張方向（図１における左側を示す）へ作動させ、上記可変容量ポンプ３の傾転角を小さくして吐出流量を下げるようになっている。   The differential pressure valve 11 is a 3-port 2-position switching valve arranged in the initial state shown in FIG. 1 by a spring 11a. When the differential pressure across the throttle 10 exceeds the set value, it is cut against the elastic force of the spring 11a. Instead, the hydraulic oil upstream of the throttle 10 is led to the piston side chamber 2b of the tilting cylinder 2, and the piston rod 2a is operated in the extending direction (showing the left side in FIG. 1) against the urging force of the coil spring 2d. Thus, the tilt angle of the variable displacement pump 3 is reduced to lower the discharge flow rate.

なお、上記アキュムレータ６には、可変容量ポンプ３から吐出する作動油の一部が常に蓄えられるようになっており、上記絞り１０と相俟って高速のサーボ弁が要求する流量変化に充分に対応できるようになっている。   The accumulator 6 always stores a part of the hydraulic oil discharged from the variable displacement pump 3, which is sufficient for the flow rate change required by the high-speed servo valve in combination with the throttle 10. It can be supported.

上記のように構成された油圧供給装置の作用を説明する。   The operation of the hydraulic pressure supply device configured as described above will be described.

上記電動機１を回転駆動させ、可変容量ポンプ３から作動油を吐出させることで、上記サーボ弁に作動油を供給して加振動作を行う。   By rotating the electric motor 1 and discharging hydraulic oil from the variable displacement pump 3, the hydraulic oil is supplied to the servo valve to perform a vibration operation.

このとき、上記サーボ弁の負荷が小さくて殆ど流量を必要としない場合には、可変容量ポンプ３からの吐出量が殆ど余剰流量となる。この余剰流量が戻し油路１２に流れ、上記絞り１０において、差圧が所定値を超え、スプリング１１ａの附勢力以上の差圧になってバルブが切り換り、絞り１０上流側の作動油を傾転シリンダ２の上記ピストン側室２ｂに導き、コイルスプリング２ｄの附勢力に抗してピストンロッド２ａを伸張方向へ作動させ、上記可変容量ポンプ３の傾転角を小さくして吐出流量を下げる。   At this time, when the load of the servo valve is small and almost no flow rate is required, the discharge amount from the variable displacement pump 3 becomes an excessive flow rate. This surplus flow rate flows into the return oil passage 12, and in the throttle 10, the differential pressure exceeds a predetermined value, the differential pressure exceeds the urging force of the spring 11a, the valve is switched, and the hydraulic oil upstream of the throttle 10 is discharged. The piston rod 2a is guided to the piston side chamber 2b of the tilting cylinder 2 to actuate the piston rod 2a in the extending direction against the urging force of the coil spring 2d, and the tilting angle of the variable displacement pump 3 is reduced to lower the discharge flow rate.

この状態で、上記サーボ弁の負荷が大きくなって多量の作動油流量を必要とする場合には、可変容量ポンプ３による吐出流量は全てサーボ弁に流れる。すると、上記戻し油路１２に流れる作動油が減少することで絞り１０前後の差圧が下がり、この差圧が上記スプリング１１ａの附勢力より小さくなると、スプリング１１ａの附勢力によって上記差圧弁１１は図１に示す初期状態に戻る。   In this state, when the load of the servo valve becomes large and a large amount of hydraulic oil flow is required, all the discharge flow rate by the variable displacement pump 3 flows to the servo valve. Then, the hydraulic oil flowing through the return oil passage 12 decreases, so that the differential pressure before and after the throttle 10 decreases. When this differential pressure becomes smaller than the urging force of the spring 11a, the differential pressure valve 11 is moved by the urging force of the spring 11a. Returning to the initial state shown in FIG.

このため、傾転シリンダ２のピストン室側２ｂの圧力が低下してコイルスプリング２ｄの附勢力に応じた位置、すなわち、可変容量ポンプ３の吐出量を増加させ、余剰流量による差圧が所定値になるよう傾転角を大きくする。   For this reason, the pressure on the piston chamber side 2b of the tilting cylinder 2 decreases to increase the position corresponding to the urging force of the coil spring 2d, that is, the discharge amount of the variable displacement pump 3, and the differential pressure due to the excess flow rate is a predetermined value. Increase the tilt angle so that

以上、詳述したように本実施例によれば、戻り油路１２に絞り１０を設けると共に、この絞り１０の前後の差圧で切り換わる差圧弁１１の作動油を用いて上記傾転シリンダ２を作動させるようにしたので、上記サーボ弁消費流量が小さい場合には、傾転シリンダ２の傾転角を小さくして可変容量ポンプ３の吐出流量を下げると共に、サーボ弁消費流量が大きくなると、傾転シリンダ２の傾転角を大きくして可変容量ポンプ３の吐出流量を上げるで、常に余剰流量を小流量で一定としたポンプ吐出制御ができて油圧源として大変効率が良い。   As described above in detail, according to the present embodiment, the tilting cylinder 2 is provided using the hydraulic oil of the differential pressure valve 11 that is provided with the throttle 10 in the return oil passage 12 and is switched by the differential pressure before and after the throttle 10. When the servo valve consumption flow rate is small, the tilt angle of the tilt cylinder 2 is reduced to lower the discharge flow rate of the variable displacement pump 3, and the servo valve consumption flow rate is increased. By increasing the tilting angle of the tilting cylinder 2 and increasing the discharge flow rate of the variable displacement pump 3, pump discharge control can be performed in which the surplus flow rate is always constant at a small flow rate, which is very efficient as a hydraulic source.

また、サーボ弁への負荷が小さくて余剰流量が多い場合には、可変容量ポンプ３の流量を下げるので、その分、油圧供給装置自体の振動や騒音が低減できる。   Further, when the load on the servo valve is small and the surplus flow rate is large, the flow rate of the variable displacement pump 3 is lowered, and accordingly, vibration and noise of the hydraulic pressure supply device itself can be reduced.

また、油路７の途中にアキュムレータ６を設けたので、可変容量ポンプ３から吐出する作動油の一部を常に蓄えることで、上記絞り１０と相俟って高速のサーボ弁が要求する流量変化に充分に対応することができる。   In addition, since the accumulator 6 is provided in the middle of the oil passage 7, by always storing a part of the hydraulic oil discharged from the variable displacement pump 3, the flow rate change required by the high-speed servo valve in combination with the throttle 10 is achieved. Can be fully accommodated.

なお、本実施の形態では、絞り１０をリリーフ弁８の上流側に設けたが、この構造に限定されるものではなく、リリーフ弁８の下流側に設けても良いことは勿論である。   In the present embodiment, the throttle 10 is provided on the upstream side of the relief valve 8, but is not limited to this structure, and may of course be provided on the downstream side of the relief valve 8.

サーボ弁を使用した加振機等の油圧源への具現化に向く。   Suitable for realization of hydraulic power sources such as vibrators using servo valves.

２ 傾転シリンダ
２ｂ ピストン側室
２ｄ コイルスプリング
３ 可変容量ポンプ
６ アキュムレータ
７ 油路
８ リリーフ弁
１０ 絞り
１１ 差圧弁
１２ 戻し油路
Ｔ タンク








2 Tilt cylinder 2b Piston side chamber 2d Coil spring 3 Variable displacement pump 6 Accumulator 7 Oil passage 8 Relief valve 10 Throttle 11 Differential pressure valve 12 Return oil passage T Tank








Claims (3)

傾転角を制御するための傾転シリンダを備えた可変容量ポンプと、この可変容量ポンプからアクチュエータに接続される油路と、この油路の途中に接続されたアキムレータと、上記油路の途中から分岐して可変容量ポンプからの余剰流量をリリーフ弁を介してタンクに戻す戻し油路とを供えた油圧供給装置であって、上記戻し油路の途中に絞りを設けると共に、この絞りの前後の差圧が設定値より大きくなると可変容量ポンプの吐出流量を減らして上記設定値に戻すよう上記傾転シリンダを作動させる差圧弁を設けたことを特徴とする油圧供給装置。   A variable displacement pump having a tilt cylinder for controlling the tilt angle, an oil passage connected from the variable displacement pump to the actuator, an accumulator connected in the middle of the oil passage, and a middle of the oil passage A hydraulic oil supply device provided with a return oil passage that branches off from the variable capacity pump and returns the excess flow rate from the variable displacement pump to the tank via a relief valve. A hydraulic pressure supply device provided with a differential pressure valve for operating the tilting cylinder so as to reduce the discharge flow rate of the variable displacement pump and return it to the set value when the differential pressure of becomes larger than the set value. 上記傾転シリンダは、ロッド室側にコイルスプリングが配置されると共に、ピストン室に上記差圧弁を介して絞り上流側の作動油が供給されることを特徴とする請求項１に記載の油圧供給装置。   2. The hydraulic pressure supply according to claim 1, wherein the tilting cylinder is provided with a coil spring on the rod chamber side, and hydraulic oil is supplied to the piston chamber on the upstream side of the throttle through the differential pressure valve. apparatus. 上記絞りは上記リリーフ弁の上流側に設けられていることを特徴とする請求項１に記載の油圧供給装置。   2. The hydraulic pressure supply device according to claim 1, wherein the throttle is provided on an upstream side of the relief valve.
JP2009076869A 2009-03-26 2009-03-26 Oil pressure supply device Pending JP2010230062A (en)

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CN107327426A (en) * 2016-01-28 2017-11-07 邓贲 A kind of force control hydraulic pressure energy saving of system method and its energy saver

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107327426A (en) * 2016-01-28 2017-11-07 邓贲 A kind of force control hydraulic pressure energy saving of system method and its energy saver
CN107327426B (en) * 2016-01-28 2018-10-19 佛山市佛锐达机电科技有限公司 A kind of force control hydraulic pressure energy saving of system method and its energy saver

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