JPH05195550A - Hydraulic actuator controller in earth-moving machine - Google Patents
Hydraulic actuator controller in earth-moving machineInfo
- Publication number
- JPH05195550A JPH05195550A JP712792A JP712792A JPH05195550A JP H05195550 A JPH05195550 A JP H05195550A JP 712792 A JP712792 A JP 712792A JP 712792 A JP712792 A JP 712792A JP H05195550 A JPH05195550 A JP H05195550A
- Authority
- JP
- Japan
- Prior art keywords
- lever
- hydraulic actuator
- control valve
- pressure
- current
- 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.)
- Granted
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、例えばバックホー等の
土工機における油圧アクチュエータ制御装置に関し、詳
しくは、作業装置を油圧アクチュエータにより駆動する
よう構成するとともに、前記油圧アクチュエータの電磁
式比例流量制御弁の開度を、操作レバーの操作量に応じ
た電流を供給して比例制御する流量制御手段を備えてあ
る土工機における油圧アクチュエータ制御装置に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic actuator control device for an earthmoving machine such as a backhoe. More specifically, the working device is configured to be driven by a hydraulic actuator, and an electromagnetic proportional flow control valve for the hydraulic actuator is provided. The present invention relates to a hydraulic actuator control device in an earthmoving machine, which is provided with a flow rate control means for proportionally controlling the opening degree of the control lever by supplying a current according to an operation amount of an operation lever.
【0002】[0002]
【従来の技術】上記土工機における油圧アクチュエータ
制御装置において、従来では、前記操作レバーの全操作
領域に亘りその操作量に応じた電流を前記電磁式比例流
量制御弁に供給するよう構成してあった。2. Description of the Related Art Conventionally, a hydraulic actuator control device for an earthmoving machine is configured to supply a current corresponding to an operation amount of the operation lever to the electromagnetic proportional flow control valve over the entire operation region. It was
【0003】[0003]
【発明が解決しようとする課題】前記制御装置は、油圧
アクチュエータの制御のための油圧制御弁のスプールを
人為的に操作するのは、操作が重く、行い難い欠点があ
るために、このレバー操作を軽快に行えるようにするた
めに、操作レバーの操作量を電気信号に変換して、供給
電流に対応した開度に比例制御される電磁式比例流量制
御弁を用いて油圧アクチュエータを操作するよう構成し
たものである。ところが、上記従来構造においては、操
作レバーの操作領域の全域に亘り、操作量に応じた電流
を供給して前記電磁式比例流量制御弁を駆動制御するよ
う構成したものであるから、レバー操作の途中において
は、操作位置に対応する電流量、即ちそれに対応する弁
開度に設定され、所望の作業速度を得ることができるけ
れども、例えば作業装置を高速で作動している状態から
急停止するような場合、操作レバーを高速作動域から素
早く中立位置側に操作しても、作業装置が慣性力に起因
して過剰作動したり、電流変化に対して電磁式比例流量
制御弁のスプールの移動が追いつかず応答遅れを生じた
りして、操作レバーの操作通り作業装置が作動せず、所
望の停止位置を越えたり、その手前で停止してしまうこ
とがあり、操縦者の意思に沿わない作動になる欠点があ
った。特に、大重量の作業装置を駆動するときに上記不
具合が顕著となっていた。本発明は上記不具合点を解消
することを目的としている。The above-mentioned control device is disadvantageous in that manually operating the spool of the hydraulic control valve for controlling the hydraulic actuator is heavy and difficult to perform. In order to facilitate the operation of the hydraulic actuator, the operation amount of the operation lever is converted into an electric signal, and the hydraulic actuator is operated using an electromagnetic proportional flow control valve that is proportionally controlled to the opening corresponding to the supply current. It is composed. However, in the above-described conventional structure, the electromagnetic proportional flow control valve is driven and controlled by supplying a current according to the operation amount over the entire operation area of the operation lever. On the way, the current amount corresponding to the operation position, that is, the valve opening corresponding to the current amount is set, and the desired working speed can be obtained, but for example, the working device is suddenly stopped from the high-speed operating state. In this case, even if the operating lever is quickly moved from the high-speed operating range to the neutral position, the working device may overact due to inertial force, or the spool of the electromagnetic proportional flow control valve may move in response to current changes. The work device may not operate according to the operation of the operating lever due to a delay in catching up, and the work device may exceed the desired stop position or may stop before that position. There is a disadvantage to be working. In particular, the above-mentioned problems have been remarkable when driving a heavy work device. The present invention aims to eliminate the above-mentioned problems.
【0004】[0004]
【課題を解決するための手段】本発明の特徴構成は、冒
頭に記載した土工機における油圧アクチュエータ制御装
置において、前記油圧アクチュエータにおける圧油供給
側の作動内圧を検出する圧力検出手段を備えるととも
に、前記操作レバーの駆動操作位置からの中立位置への
切り換え操作時において、前記圧力検出手段の検出値が
所定値以上にまで上昇する間のみ、前記電磁式比例流量
制御弁に逆方向電流を供給する逆方向電流供給手段を備
えてある点にある。According to a characteristic configuration of the present invention, in the hydraulic actuator control device for an earthmoving machine described at the beginning, pressure detecting means for detecting an operating internal pressure on the pressure oil supply side of the hydraulic actuator is provided, and During the switching operation from the drive operation position of the operation lever to the neutral position, the reverse current is supplied to the electromagnetic proportional flow control valve only while the detection value of the pressure detection means rises to a predetermined value or more. It is provided with a reverse current supply means.
【0005】[0005]
【作用】例えば、作業装置を比較的高速で作動させてい
る状態から急停止させるために、操作レバーを駆動状態
から中立位置まで戻し操作すると、それまで電磁式比例
流量制御弁に対して供給されていた電流方向とは反対方
向の逆方向電流を供給するので、慣性力や応答遅れ等に
起因して所望停止位置を越えて作業装置が過剰作動しよ
うとするのに対して、油圧アクチュエータに逆方向の圧
油を供給することになる。その結果、この逆方向の油圧
力により上記過剰作動を抑制するようブレーキ力が働
き、作業装置の停止作動が操縦者のレバー操作感覚に極
力合致させることができる。しかも、油圧アクチュエー
タにおける圧油供給側の内圧が、前記逆方向の油圧に起
因する押し戻し作用による圧力上昇が所定値に達した後
は、前記逆方向電流の供給が停止されるので、油圧アク
チュエータが作動方向と反対側に作動されるのを未然に
阻止できる。For example, when the operating lever is returned from the driving state to the neutral position in order to suddenly stop the working device from a relatively high speed state, the electromagnetic proportional flow control valve is supplied until then. Since the reverse current is supplied in the opposite direction to the current direction, the work device tries to operate excessively beyond the desired stop position due to inertial force, response delay, etc. Direction pressure oil will be supplied. As a result, the braking force works to suppress the excessive operation due to the hydraulic pressure in the opposite direction, and the stop operation of the working device can be made to match the lever operation feeling of the operator as much as possible. Moreover, since the internal pressure on the pressure oil supply side of the hydraulic actuator reaches the predetermined value due to the pressure increase due to the push-back action due to the hydraulic pressure in the reverse direction, the supply of the reverse current is stopped, so that the hydraulic actuator is It can be prevented from being actuated on the side opposite to the actuating direction.
【0006】[0006]
【発明の効果】従って、油圧制御弁を電気制御式に構成
して、レバー操作を軽快に楽に行えるものでありなが
ら、高速作動する作業装置を急停止させる場合、ほぼレ
バー操作感覚に適応するよう確実な停止作動を実現でき
るものを提供できるに到った。しかも、油圧アクチュエ
ータの内圧を検出することで、逆方向電流の供給を不必
要に長くさせて操縦者の意に反して作業装置が逆方向に
振れ戻し作動する等の弊害を確実に防止できるととも
に、作業装置の停止に伴うショックの発生を抑制できる
ものとなった。Therefore, although the hydraulic control valve is electrically controlled so that the lever operation can be performed lightly and easily, when the working device that operates at high speed is suddenly stopped, it is almost adapted to the lever operation feeling. It has come to be possible to provide a device that can realize a reliable stop operation. Moreover, by detecting the internal pressure of the hydraulic actuator, it is possible to reliably prevent adverse effects such as unnecessarily lengthening the supply of reverse current and causing the working device to swing back in the opposite direction against the operator's intention. , It became possible to suppress the occurrence of shock due to the stop of the working device.
【0007】[0007]
【実施例】以下、実施例を図面に基いて説明する。図4
に土工機の一例としてのバックホーを示している。この
バックホーは、クローラ走行装置1を備えた走行機台2
に旋回用油圧モータMの駆動により縦軸芯周りで全旋回
自在に旋回台3を搭載するとともに、旋回台3にバック
ホー装置4〔作業装置の一例〕を連結し、走行機台2に
ドーザ装置5を備えて構成してある。前記バックホー装
置4は、旋回台3に横軸芯周りで上下揺動自在に枢支さ
れるブーム6にアーム7、バケット8を枢支連結すると
ともに、夫々をブームシリンダC1、アームシリンダC
2、バケットシリンダC3により駆動揺動して掘削作業
を行えるよう構成してある。又、ブーム6は、基端部6
a、中間部6b及び先端部6cに3分割され、夫々を縦
軸芯周りで枢支連結するとともに、基端部6aと先端部
6cとを中間部6bと平行なリンク9を介して枢支連結
し、オフセットシリンダC4により中間部6bを揺動駆
動することでバケット8が平行姿勢を維持しながら左右
方向に移動できるよう構成し、バケット8をブーム基端
部6aに対して横方向にオフセットして旋回台3上に格
納することで最大旋回径を小さくした状態で旋回作動で
きるよう構成してある。Embodiments will be described below with reference to the drawings. Figure 4
Shows a backhoe as an example of an earthmoving machine. This backhoe has a traveling platform 2 equipped with a crawler traveling device 1.
A swivel base 3 is mounted on the swivel base 3 such that the swivel base 3 can be freely swiveled around a vertical axis by driving a swiveling hydraulic motor M. It is configured with 5. The backhoe device 4 pivotally supports an arm 7 and a bucket 8 on a boom 6 which is pivotally supported on a swivel base 3 about a horizontal axis so as to be vertically swingable, and also has a boom cylinder C1 and an arm cylinder C, respectively.
2. The bucket cylinder C3 is driven and rocked to perform excavation work. Also, the boom 6 has a base end 6
a, an intermediate portion 6b, and a tip portion 6c are divided into three parts, and each of them is pivotally connected about a longitudinal axis, and the base end portion 6a and the tip portion 6c are pivotally supported via a link 9 parallel to the intermediate portion 6b. The bucket 8 is configured to be movable laterally while maintaining a parallel posture by swinging the intermediate portion 6b by connecting the offset cylinder C4, and the bucket 8 is laterally offset with respect to the boom base end portion 6a. By storing it on the swivel base 3, the swivel operation can be performed with the maximum swivel diameter reduced.
【0008】油圧アクチュエータとしての前記ブームシ
リンダC1、アームシリンダC2、バケットシリンダC
3及び旋回油圧モータMの夫々は、旋回台3上に設けら
れた操縦部10に配設した十字揺動操作自在な左右一対
の操作レバー11により制御操作されるよう構成してあ
る。詳述すると、図1に示すように、前記各シリンダC
1,C2,C3及び旋回モータMは、夫々電磁式比例流
量制御弁Vにより油圧流量を制御するよう構成し、各操
作レバー11の夫々の操作方向における操作量を4個の
ポテンショメータPMにより検出して、この検出操作量
に基づいて制御装置12が各電磁式比例流量制御弁Vに
対する電流供給量を制御するよう構成してある。又、前
記オフセットシリンダC4は操作スイッチSWの操作に
より予め設定される流量を供給するよう構成されてい
る。前記各シリンダC1,C2,C3及び旋回モータM
に対する夫々の圧油供給路には、作動内圧を検出する圧
力センサS〔圧力検出手段の一例〕を設けてある。前記
制御装置12は、操作レバー11の操作量に応じた電流
を供給して電磁式比例流量制御弁Vの開度を比例制御す
る流量制御手段Aと、操作レバー11の駆動操作位置か
らの中立位置への切り換え操作時において、前記操作レ
バー11による作動領域のうち、高速作動側の所定の領
域内における前記操作レバー11の操作速度が所定値以
上であることを検出したときのみ、前記操作レバー11
が中立位置に操作された時点から所定の短時間だけ前記
電磁式比例流量制御弁Vに逆方向電流を供給する逆方向
電流供給手段Bとを制御プログラム形式で備えてある。
つまり、制御装置12は以下のように制御を実行する。
以下、油圧アクチュエータの一例としてのブームシリン
ダC1の作動制御について説明する。図2に示すよう
に、操作レバー11により操作されるブームシリンダC
1操作用のポテンショメータPM〔操作速度検出手段の
一例〕の出力X1及びブーム6の圧油供給側における前
記圧力センサSの出力を読み込み〔ステップ1,2〕、
ポテンショメータの出力X1の変化より操作レバー11
の操作速度X2を演算する〔ステップ3〕。そして、ブ
ームシリンダC1を減速させる方向へのレバー操作が行
われ、かつ、ポテンショメータPMの出力X1〔レバー
操作位置〕が所定値aよりも大であって、更に、その位
置でのレバー操作速度X2が所定値b以上である場合に
〔ステップ4,5,6〕、予め定められるマップデータ
に基づいて前記レバー速度X2により逆方向電流Iの電
流値を決定する〔ステップ7〕。又、操作レバー11が
中立不感帯内に操作されるまで、予め定まる特性に基づ
いて電磁式比例流量制御弁Vに対してレバー操作量に対
応した制御目標電流Irを供給して開度を比例制御する
〔ステップ8,9〕。そして、操作レバー11が中立不
感帯内に入ったとき、その時点から前記圧力センサSの
出力Pが所定値P1まで上昇するまで、前記逆方向電流
Iを電磁式比例流量制御弁Vに対して供給する〔ステッ
プ10〜12〕。つまり、図3に示すように、逆方向電
流を供給することで圧油供給路と反対側の圧油路の圧力
が上昇して、その押し戻し作用により当該圧油供給路側
の内圧が再度上昇しはじめるが、その再上昇において少
し上昇しかかった所定値P1に到るまで逆方向電流Iを
供給するのである。又、前記ステップ5,6,7におい
て条件が満たされない場合には、予め定まる特性に基づ
いて電磁式比例流量制御弁Vに対してレバー操作量に対
応した制御目標電流Irを供給して開度を比例制御する
〔ステップ13〕。上記したような制御をリセットされ
るまで所定時間毎に繰り返す〔ステップ14〕。前記ス
テップ8,13により流量制御手段Aを構成し、前記ス
テップ10〜12により逆方向電流供給手段Bを構成す
る。上記したような制御はブーム6の作動制御に限ら
ず、その他の油圧アクチュエータの制御に用いてもよ
く、前記逆方向電流の電流値は無条件に一定に設定する
ものでもよい。The boom cylinder C1, the arm cylinder C2, and the bucket cylinder C as hydraulic actuators.
3 and the swing hydraulic motor M are configured to be controlled and controlled by a pair of left and right operation levers 11 which are provided in a control unit 10 provided on the swivel base 3 and which are capable of swinging in a cross motion. More specifically, as shown in FIG. 1, each of the cylinders C
1, C2, C3 and the swing motor M are configured to control the hydraulic flow rate by the electromagnetic proportional flow rate control valve V, respectively, and the operation amount of each operation lever 11 in each operation direction is detected by the four potentiometers PM. Then, the control device 12 is configured to control the current supply amount to each electromagnetic proportional flow control valve V based on the detected manipulated variable. The offset cylinder C4 is configured to supply a preset flow rate by operating the operation switch SW. The cylinders C1, C2, C3 and the turning motor M
A pressure sensor S (an example of a pressure detecting means) for detecting the working internal pressure is provided in each pressure oil supply path for the. The control device 12 supplies a current according to the operation amount of the operation lever 11 to proportionally control the opening of the electromagnetic proportional flow control valve V, and a neutral position from the drive operation position of the operation lever 11. During the switching operation to the position, the operation lever is detected only when it is detected that the operation speed of the operation lever 11 in a predetermined area on the high-speed operation side of the operation area of the operation lever 11 is a predetermined value or more. 11
Is provided in a control program format with a reverse current supply means B for supplying a reverse current to the electromagnetic proportional flow control valve V for a predetermined short time from the time when is operated to the neutral position.
That is, the control device 12 executes the control as follows.
Hereinafter, operation control of the boom cylinder C1 as an example of the hydraulic actuator will be described. As shown in FIG. 2, the boom cylinder C operated by the operation lever 11
The output X1 of the potentiometer PM for one operation [an example of operation speed detecting means] and the output of the pressure sensor S on the pressure oil supply side of the boom 6 are read [steps 1 and 2],
From the change in potentiometer output X1, the operating lever 11
The operation speed X2 is calculated [step 3]. Then, the lever operation in the direction of decelerating the boom cylinder C1 is performed, the output X1 [lever operation position] of the potentiometer PM is larger than the predetermined value a, and further, the lever operation speed X2 at that position. Is greater than or equal to the predetermined value b [steps 4, 5, 6], the current value of the reverse current I is determined by the lever speed X2 based on the predetermined map data [step 7]. Further, until the operating lever 11 is operated within the neutral dead zone, the control target current Ir corresponding to the lever operation amount is supplied to the electromagnetic proportional flow rate control valve V based on a predetermined characteristic to proportionally control the opening. [Steps 8 and 9]. Then, when the operating lever 11 enters the neutral dead zone, the reverse current I is supplied to the electromagnetic proportional flow control valve V from that point until the output P of the pressure sensor S rises to a predetermined value P1. [Steps 10-12]. That is, as shown in FIG. 3, by supplying a reverse current, the pressure in the pressure oil passage on the opposite side of the pressure oil supply passage increases, and the pushing back action increases the internal pressure on the pressure oil supply passage side again. First, the reverse current I is supplied until reaching a predetermined value P1 which is about to rise a little in the re-rise. If the conditions are not satisfied in steps 5, 6 and 7, the control target current Ir corresponding to the lever operation amount is supplied to the electromagnetic proportional flow rate control valve V based on a predetermined characteristic to open the opening. Is proportionally controlled [step 13]. The above control is repeated every predetermined time until it is reset [step 14]. The steps 8 and 13 constitute the flow rate control means A, and the steps 10 to 12 constitute the reverse current supply means B. The above control is not limited to the operation control of the boom 6, but may be used for control of other hydraulic actuators, and the current value of the reverse current may be set unconditionally constant.
【0009】尚、特許請求の範囲の項に図面との対照を
容易にするために符号を記すが、該記入により本発明は
添付図面の構成に限定されるものではない。It should be noted that although reference numerals are given in the claims for facilitating the comparison with the drawings, the present invention is not limited to the configuration of the accompanying drawings by the entry.
【図1】制御ブロック図FIG. 1 is a control block diagram.
【図2】制御フローチャート[Fig. 2] Control flowchart
【図3】制御特性図[Fig. 3] Control characteristic diagram
【図4】バックホーの側面図FIG. 4 is a side view of the backhoe.
4 作業装置 11 操作レバー A 流量制御手段 B 逆方向電流供給手段 S 圧力検出手段 V 電磁式比例流量制御弁 4 Working Device 11 Operation Lever A Flow Control Means B Reverse Current Supply Means S Pressure Detection Means V Electromagnetic Proportional Flow Control Valves
───────────────────────────────────────────────────── フロントページの続き (72)発明者 森下 勇太郎 大阪府堺市石津北町64番地 株式会社クボ タ堺製造所内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yutaro Morishita 64 Ishizukita-machi, Sakai City, Osaka Prefecture Kubota Sakai Factory Co., Ltd.
Claims (1)
より駆動するよう構成するとともに、前記油圧アクチュ
エータの電磁式比例流量制御弁(V)の開度を、操作レ
バー(11)の操作量に応じた電流を供給して比例制御
する流量制御手段(A)を備えてある土工機における油
圧アクチュエータ制御装置であって、前記油圧アクチュ
エータにおける圧油供給側の作動内圧を検出する圧力検
出手段(S)を備えるとともに、前記操作レバー(1
1)の駆動操作位置からの中立位置への切り換え操作時
において、前記圧力検出手段(S)の検出値が所定値以
上にまで上昇する間のみ、前記電磁式比例流量制御弁
(V)に逆方向電流を供給する逆方向電流供給手段
(B)を備えてある土工機における油圧アクチュエータ
制御装置。1. A working device (4) is configured to be driven by a hydraulic actuator, and an opening of an electromagnetic proportional flow rate control valve (V) of the hydraulic actuator is set according to an operation amount of an operating lever (11). A hydraulic actuator control device for an earthmoving machine equipped with a flow rate control means (A) for supplying an electric current and performing proportional control, comprising pressure detection means (S) for detecting an operating internal pressure of the hydraulic actuator on the pressure oil supply side. The operation lever (1
During the switching operation from the drive operation position to the neutral position of 1), only when the detected value of the pressure detecting means (S) rises above a predetermined value, the solenoid proportional flow control valve (V) is reversed. A hydraulic actuator control device in an earthmoving machine, comprising a reverse current supply means (B) for supplying a directional current.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP712792A JP2651076B2 (en) | 1992-01-20 | 1992-01-20 | Hydraulic actuator control device for earth moving machine |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP712792A JP2651076B2 (en) | 1992-01-20 | 1992-01-20 | Hydraulic actuator control device for earth moving machine |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH05195550A true JPH05195550A (en) | 1993-08-03 |
JP2651076B2 JP2651076B2 (en) | 1997-09-10 |
Family
ID=11657418
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP712792A Expired - Lifetime JP2651076B2 (en) | 1992-01-20 | 1992-01-20 | Hydraulic actuator control device for earth moving machine |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP2651076B2 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102730566A (en) * | 2012-06-29 | 2012-10-17 | 三一重工股份有限公司 | Stepless shifting device, stepless shifting method, and tower crane |
-
1992
- 1992-01-20 JP JP712792A patent/JP2651076B2/en not_active Expired - Lifetime
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102730566A (en) * | 2012-06-29 | 2012-10-17 | 三一重工股份有限公司 | Stepless shifting device, stepless shifting method, and tower crane |
Also Published As
Publication number | Publication date |
---|---|
JP2651076B2 (en) | 1997-09-10 |
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