JPH0374290B2 - - Google Patents
Info
- Publication number
- JPH0374290B2 JPH0374290B2 JP60132020A JP13202085A JPH0374290B2 JP H0374290 B2 JPH0374290 B2 JP H0374290B2 JP 60132020 A JP60132020 A JP 60132020A JP 13202085 A JP13202085 A JP 13202085A JP H0374290 B2 JPH0374290 B2 JP H0374290B2
- Authority
- JP
- Japan
- Prior art keywords
- pressure
- main
- valve
- switching valve
- relief 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 - Lifetime
Links
- 230000001105 regulatory effect Effects 0.000 claims description 13
- 238000009412 basement excavation Methods 0.000 description 4
- 230000002265 prevention Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 230000003213 activating effect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000007935 neutral effect Effects 0.000 description 2
- 238000012423 maintenance Methods 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
- E02F9/20—Drives; Control devices
- E02F9/22—Hydraulic or pneumatic drives
- E02F9/2203—Arrangements for controlling the attitude of actuators, e.g. speed, floating function
Landscapes
- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Civil Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- Operation Control Of Excavators (AREA)
- Control And Safety Of Cranes (AREA)
- Fluid-Pressure Circuits (AREA)
Description
【発明の詳細な説明】
〔発明の利用分野〕
本発明はクレーン作業を兼用可能な油圧シヨベ
ル等の掘削機の油圧回路に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a hydraulic circuit for an excavator such as a hydraulic excavator that can also be used for crane work.
第２図は掘削機の一例として挙げた油圧シヨベ
ルの側面図である。この図において、１はブー
ム、２はアーム、３はバケツトで、これらによつ
て掘削作業をおこなうフロントアタツチメントが
構成されている。また、４はブーム１を回動させ
るブームシリンダ、５はアーム２を回動させるア
ームシリンダ、６はバケツト３を回動させるバケ
ツトシリンダで、これらはフロントアタツチメン
トを駆動するアクチユエータを構成している。
FIG. 2 is a side view of a hydraulic excavator taken as an example of an excavator. In this figure, 1 is a boom, 2 is an arm, and 3 is a bucket, which together constitute a front attachment for performing excavation work. Further, 4 is a boom cylinder that rotates the boom 1, 5 is an arm cylinder that rotates the arm 2, and 6 is a bucket cylinder that rotates the bucket 3, and these constitute an actuator that drives the front attachment. ing.
第３図は第２図に示す油圧シヨベルに備えられ
る従来の油圧回路の基本構成を示す回路図であ
る。この第３図に示す４は前述したブームシリン
ダである。また、１０はブームシリンダ４に圧油
を供給する主ポンプ、１７はブームシリンダ４と
主ポンプ１０との間に設けられ、ブームシリンダ
４に供給される圧油の量、流れ方向を制御し、パ
イロツト圧によつて切換えられる主切換弁、１２
はこの主切換弁１７を切換えるパイロツト弁、２
１はこのパイロツト弁１２の操作レバー、１１は
パイロツト弁１２を介して主切換弁１７を切換え
るパイロツト圧を供給するパイロツトポンプ、１
３はタンクである。また、１４は主ポンプ１０か
ら吐出される圧油の圧力を規定する主リリーフ
弁、１８は主切換弁１７が中立位置にあるときの
回路保全のために設けられる過負荷防止弁であ
る。通常、過負荷防止弁１８の設定圧P2は主リ
リーフ弁１４の設定圧P1に比べて大きく設定さ
れる。 FIG. 3 is a circuit diagram showing the basic configuration of a conventional hydraulic circuit provided in the hydraulic excavator shown in FIG. 2. 4 shown in FIG. 3 is the boom cylinder described above. Further, 10 is a main pump that supplies pressure oil to the boom cylinder 4, 17 is provided between the boom cylinder 4 and the main pump 10, and controls the amount and flow direction of the pressure oil supplied to the boom cylinder 4, Main switching valve switched by pilot pressure, 12
is a pilot valve that switches this main switching valve 17;
1 is a control lever for this pilot valve 12; 11 is a pilot pump that supplies pilot pressure to switch the main switching valve 17 via the pilot valve 12;
3 is a tank. Further, 14 is a main relief valve that regulates the pressure of the pressure oil discharged from the main pump 10, and 18 is an overload prevention valve provided for circuit maintenance when the main switching valve 17 is in the neutral position. Normally, the set pressure P 2 of the overload prevention valve 18 is set larger than the set pressure P 1 of the main relief valve 14 .
そして、この第３図に示す油圧回路にあつて
は、操作レバー２１を操作すると、パイロツトポ
ンプ１１からの圧油がパイロツト弁１２を経て主
切換弁１７の駆動部に作用し、主切換弁１７が同
第３図の左位置、あるいは右位置に切換えられ、
ブームシリンダ４に主ポンプ１０からの圧油が供
給されて、当該ブームシリンダ４は伸長、あるい
は収縮する。なお、主リリーフ弁１４により主ポ
ンプ１０から吐出される油圧力はP1以下に保た
れているので、ブームシリンダ４を伸縮する油圧
力は最大P1までとなる。 In the hydraulic circuit shown in FIG. 3, when the operating lever 21 is operated, the pressure oil from the pilot pump 11 acts on the drive section of the main switching valve 17 via the pilot valve 12. is switched to the left position or right position in Figure 3,
Pressure oil is supplied from the main pump 10 to the boom cylinder 4, and the boom cylinder 4 is expanded or contracted. Note that, since the hydraulic pressure discharged from the main pump 10 is kept below P1 by the main relief valve 14, the hydraulic pressure for expanding and contracting the boom cylinder 4 is up to a maximum of P1 .
また、操作レバー２１が中立位置に保たれてい
る場合には、ブームシリンダ４の回路圧は過負荷
防止弁１８で設定される圧力P2、すなわち前述
したように主リリーフ弁１４で設定される圧力
P1よりも大きな圧力に保たれ、これによつてブ
ームシリンダ４に作用する過負荷による回路の損
傷の防止が図られている。 Furthermore, when the operating lever 21 is kept in the neutral position, the circuit pressure of the boom cylinder 4 is the pressure P 2 set by the overload prevention valve 18, that is, the pressure P 2 is set by the main relief valve 14 as described above. pressure
The pressure is maintained at a level greater than P 1 to prevent damage to the circuit due to overload acting on the boom cylinder 4.
ところで、このような油圧回路を有する油圧シ
ヨベルにあつては、バケツト３による土砂等の掘
削を主たる作業としているが、しばしばバケツト
３等にフツクなどを取付け、ワイヤロープを介し
て重量物の吊り上げ作業（クレーン作業）をおこ
なう場合がある。このような吊り上げ作業に際し
ては、フロントを持上げる力はブームシリンダ４
に作用する油圧力によつて決まるが、上記した従
来の油圧回路にあつては主リリーフ弁１４の設定
圧P1によつて制限され、したがつてそれ以上大
きな油圧力が得られず、吊り上げ力が抑えられ、
この吊り上げ作業の能率の向上を図り難い不具合
がある。 By the way, with a hydraulic excavator having such a hydraulic circuit, the main work is excavating earth and sand using the bucket belt 3, but often a hook or the like is attached to the bucket belt 3, etc., and lifting work of heavy objects is carried out via a wire rope. (crane work) may be performed. During such lifting work, the force to lift the front is generated by boom cylinder 4.
However, in the conventional hydraulic circuit described above, it is limited by the set pressure P1 of the main relief valve 14, and therefore no greater hydraulic pressure can be obtained, and the lifting Power is suppressed,
There is a problem in that it is difficult to improve the efficiency of this lifting work.
本発明は、このような従来技術における実情に
鑑みてなされたもので、その目的は、吊り上げ作
業に際して主リリーフ弁で規定される油圧力より
も大きな油圧力を得ることができる掘削機の油圧
回路を提供することにある。
The present invention has been made in view of the actual situation in the prior art, and its purpose is to provide a hydraulic circuit for an excavator that can obtain a hydraulic pressure greater than the hydraulic pressure specified by the main relief valve during lifting work. Our goal is to provide the following.
この目的を達成するために本発明は、フロント
アタツチメントを駆動するアクチユエータに圧油
を供給する主ポンプと、この主ポンプから吐出さ
れる圧油の圧力を規定する主リリーフ弁とを備え
た掘削機の油圧回路において、上記主ポンプから
吐出される圧油の圧力を上記主リリーフ弁の設定
圧に比べて大きくなるように規定する設定圧規定
手段と、オペレータの意図に応じて操作され、こ
の設定圧規定手段を作動させる指令信号を出力す
る指令手段とを備えるとともに、上記指令手段を
上記アクチユエータを駆動する操作レバーに設け
た構成にしてある。
To achieve this objective, the present invention includes a main pump that supplies pressure oil to an actuator that drives a front attachment, and a main relief valve that regulates the pressure of the pressure oil discharged from the main pump. In the hydraulic circuit of the excavator, a set pressure regulating means for regulating the pressure of pressure oil discharged from the main pump to be greater than a set pressure of the main relief valve, and a set pressure regulating means operated according to the intention of an operator, A command means for outputting a command signal for activating the set pressure regulating means is provided, and the command means is provided on an operating lever that drives the actuator.
以下、本発明の掘削機の油圧回路を図に基づい
て説明する。第１図は本発明の一実施例を示す回
路図である。なお、この図において、前述した第
３図に示すものと同じものは同一符号で示してあ
る。
Hereinafter, the hydraulic circuit of the excavator of the present invention will be explained based on the drawings. FIG. 1 is a circuit diagram showing an embodiment of the present invention. In this figure, the same parts as those shown in FIG. 3 described above are designated by the same reference numerals.
この第１図において、１６は主ポンプ１０とタ
ンク１３とを連絡する管路に介設され、パイロツ
ト圧により切換えられる切換弁、１５は切換弁１
６とタンク１３との間に介設したリリーフ弁で、
このリリーフ弁１５の設定圧P3は主リリーフ弁
１４の設定圧P1よりも大きく、例えば過負荷防
止弁１８の設定圧P2とほぼ同等の大きさに設定
されている。２０はパイロツト弁１２から主切換
弁１７に導かれるパイロツト圧を取出すシヤトル
弁、１９はシヤトル弁２０と切換弁１６との間に
設けられる電磁切換弁である。上記したリリーフ
弁１５、切換弁１６、電磁切換弁１９、シヤトル
弁２０等によつて、主ポンプ１０から吐出される
圧油の圧力を主リリーフ弁１４の設定圧に比べて
大きくなるように規定する設定圧規定手段が構成
されている。 In FIG. 1, reference numeral 16 indicates a switching valve that is installed in a pipe connecting the main pump 10 and the tank 13 and is switched by pilot pressure, and 15 indicates a switching valve 1.
With a relief valve interposed between 6 and tank 13,
The set pressure P 3 of the relief valve 15 is set to be larger than the set pressure P 1 of the main relief valve 14 and approximately equal to the set pressure P 2 of the overload prevention valve 18, for example. Reference numeral 20 is a shuttle valve that takes out pilot pressure guided from the pilot valve 12 to the main switching valve 17, and 19 is an electromagnetic switching valve provided between the shuttle valve 20 and the switching valve 16. The pressure of the pressure oil discharged from the main pump 10 is regulated to be higher than the set pressure of the main relief valve 14 by the relief valve 15, switching valve 16, electromagnetic switching valve 19, shuttle valve 20, etc. described above. A set pressure regulating means is configured.
２２は上述の設定圧規定手段を作動させる操作
信号を出力する指令手段、例えば操作レバー２１
に装着されるスイツチで、このスイツチ２２が
ONになると電磁切換弁１９は同第１図の上段に
切換えられるようになつている。 Reference numeral 22 denotes a command means for outputting an operation signal for activating the above-mentioned set pressure regulating means, such as the operation lever 21.
This switch 22 is a switch installed in
When turned ON, the electromagnetic switching valve 19 is switched to the upper stage in FIG. 1.
この実施例にあつては、通常の掘削作業に際し
ては、スイツチ２２がOFFのままであることか
ら、設定圧規定手段は作動せず、すなわち、電磁
切換弁１９は同第１図に示すように下段位置に保
たれ、したがつて切換弁１６の駆動部はタンク１
３に連通され、ばねの力によつて該切換弁１６は
上段位置に保たれ、主ポンプ１０とリリーフ弁１
５との接続が断たれた状態にある。そして、掘削
作業をおこなうにはスイツチ２２をOFFにした
まま操作レバー２１を操作すればよく、これによ
つて前述した第３図におけるのと同様にして、パ
イロツトポンプ１１からの圧油がパイロツト弁１
２を経て主切換弁１７の駆動部に作用し、主切換
弁１７が切換えられ、ブームシリンダ４に主ポン
プ１０からの圧油が供給され、ブームシリンダ４
が伸縮し、所望の掘削作業がおこなわれる。 In this embodiment, during normal excavation work, since the switch 22 remains OFF, the set pressure regulating means does not operate, that is, the electromagnetic switching valve 19 operates as shown in FIG. Therefore, the drive part of the switching valve 16 is kept in the lower position.
3, the switching valve 16 is kept in the upper position by the force of the spring, and the main pump 10 and the relief valve 1
5 has been disconnected. To carry out excavation work, it is only necessary to operate the control lever 21 with the switch 22 turned OFF, and this causes the pressure oil from the pilot pump 11 to flow through the pilot valve in the same manner as in FIG. 1
2 acts on the driving part of the main switching valve 17, the main switching valve 17 is switched, pressure oil from the main pump 10 is supplied to the boom cylinder 4, and the boom cylinder 4
expands and contracts, and the desired excavation work is performed.
また、重量物等の吊り上げ作業に際しては、ス
イツチ２２をONにした状態で操作レバー２１を
操作すればよい。すなわち、スイツチ２２をON
にすると電磁切換弁１９が上段位置に切換えら
れ、操作レバー２１の操作に伴つて主切換弁１７
にパイロツト圧が供給されると、該パイロツト圧
がシヤトル弁２０によつて検出され、該パイロツ
ト圧が電磁切換弁１９を経て切換弁１６の駆動部
に導かれ、これによつて切換弁１６は下段位置に
切換えられ、主ポンプ１０とリリーフ弁１５が接
続するとともに、主ポンプ１０と主リリーフ弁１
４との接続が断たれる。そして、主ポンプ１０か
らの圧油が主切換弁１７を介してブームシリンダ
４に供給され、該ブームシリンダ４が伸縮して重
量物の吊り上げ作業がおこなわれる。この場合、
主ポンプ１０から吐出される圧油の圧力はリリー
フ弁１５の設定圧P3によつて制限されるので、
ブームシリンダ４における油圧力は最大で設定圧
P3までの大きなものとなり、したがつて最大で
設定圧P1（＜P3）であつたときに比べて当該吊り
上げ作業の能率を向上させることができる。 Furthermore, when lifting a heavy object or the like, the operating lever 21 may be operated with the switch 22 turned on. In other words, switch 22 is turned on.
When the solenoid switching valve 19 is switched to the upper position, the main switching valve 17 is switched to the upper position as the operating lever 21 is operated.
When pilot pressure is supplied to the valve, the pilot pressure is detected by the shuttle valve 20, and the pilot pressure is guided to the driving part of the switching valve 16 via the electromagnetic switching valve 19, whereby the switching valve 16 is activated. Switched to the lower position, the main pump 10 and the relief valve 15 are connected, and the main pump 10 and the main relief valve 1 are connected.
4 is disconnected. Pressure oil from the main pump 10 is supplied to the boom cylinder 4 via the main switching valve 17, and the boom cylinder 4 expands and contracts to perform lifting work of heavy objects. in this case,
Since the pressure of the pressure oil discharged from the main pump 10 is limited by the set pressure P3 of the relief valve 15,
The maximum hydraulic pressure in boom cylinder 4 is the set pressure.
Therefore, the efficiency of the lifting work can be improved compared to when the maximum set pressure is P 1 (< P 3 ) .
なお、上記実施例では、ブームシリンダ４の駆
動回路に適用した例を挙げたが、アームシリン
ダ、バケツトシリンダにあつても必要に応じてほ
ぼ同等に構成することができる。 In the above embodiment, an example was given in which the present invention was applied to the drive circuit of the boom cylinder 4, but the structure can be substantially the same for an arm cylinder or a bucket cylinder, if necessary.
また、上記実施例にあつては設定圧規定手段が
電磁切換弁１９を含む構成にしてあるが、本発明
はこれに限らず、電磁切換弁１９の代りにパイロ
ツト圧によつて切換えられる切換弁を設けること
もできる。 Further, in the above embodiment, the set pressure regulating means includes the electromagnetic switching valve 19, but the present invention is not limited to this, and instead of the electromagnetic switching valve 19, a switching valve that is switched by pilot pressure is used. It is also possible to provide
また、上記実施例では、設定圧規定手段がパイ
ロツト圧によつて切換えられる切換弁１６を含む
構成にしてあるが、本発明はこれに限られず、切
換弁１６の代りにスイツチ２２のON、OFFによ
つて切換えられる電磁切換弁を設け、第１図に示
す電磁切換弁１９、シヤトル弁２０等を除く構成
とすることもできる。 Further, in the above embodiment, the set pressure regulating means includes the switching valve 16 that is switched by the pilot pressure, but the present invention is not limited to this. It is also possible to provide a configuration in which an electromagnetic switching valve that can be switched by is provided, and the electromagnetic switching valve 19, shuttle valve 20, etc. shown in FIG. 1 are omitted.
本発明の掘削機の油圧回路は、以上のように構
成してあることから、吊り上げ作業に際して主リ
リーフ弁で規定される油圧力よりも大きな油圧力
を得ることができ、それ故、当該吊り上げ作業の
能率が向上する効果がある。
Since the hydraulic circuit of the excavator of the present invention is configured as described above, it is possible to obtain a hydraulic pressure greater than the hydraulic pressure prescribed by the main relief valve during lifting work, and therefore, This has the effect of improving efficiency.
第１図は本発明の掘削機の油圧回路の一実施例
を示す回路図、第２図は掘削機の一例として挙げ
た油圧シヨベルの側面図、第３図は従来の油圧回
路の基本構成を示す回路図である。
４……ブームシリンダ、１０……主ポンプ、１
１……パイロツトポンプ、１２……パイロツト
弁、１３……タンク、１４……主リリーフ弁、１
５……リリーフ弁、１６……切換弁、１７……主
切換弁、１９……電磁切換弁、２０……シヤトル
弁、２１……操作レバー、２２……スイツチ。
Fig. 1 is a circuit diagram showing an embodiment of the hydraulic circuit of an excavator according to the present invention, Fig. 2 is a side view of a hydraulic shovel taken as an example of an excavator, and Fig. 3 shows the basic configuration of a conventional hydraulic circuit. FIG. 4...Boom cylinder, 10...Main pump, 1
1... Pilot pump, 12... Pilot valve, 13... Tank, 14... Main relief valve, 1
5... Relief valve, 16... Switching valve, 17... Main switching valve, 19... Solenoid switching valve, 20... Shuttle valve, 21... Operation lever, 22... Switch.
Claims (1)
エータに圧油を供給する主ポンプと、この主ポン
プから吐出される圧油の圧力を規定する主リリー
フ弁とを備えた掘削機の油圧回路において、上記
主ポンプから吐出される圧油の圧力を上記主リリ
ーフ弁の設定圧に比べて大きくなるように規定す
る設定圧規定手段と、オペレータの意図に応じて
操作され、この設定圧規定手段を作動させる指令
信号を出力する指令手段とを備えるとともに、上
記指令手段を上記アクチユエータを駆動する操作
レバーに設けたことを特徴とする掘削機の油圧回
路。1. In the hydraulic circuit of an excavator equipped with a main pump that supplies pressure oil to an actuator that drives a front attachment, and a main relief valve that regulates the pressure of the pressure oil discharged from the main pump, the main pump a set pressure regulating means for regulating the pressure of the pressurized oil discharged from the main relief valve to be greater than the set pressure of the main relief valve; and a command signal operated according to the operator's intention to activate the set pressure regulating means. A hydraulic circuit for an excavator, comprising: a command means for outputting the command means, and the command means is provided on an operating lever that drives the actuator.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60132020A JPS61294031A (en) | 1985-06-19 | 1985-06-19 | Oil-pressure circuit for excavator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60132020A JPS61294031A (en) | 1985-06-19 | 1985-06-19 | Oil-pressure circuit for excavator |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61294031A JPS61294031A (en) | 1986-12-24 |
| JPH0374290B2 true JPH0374290B2 (en) | 1991-11-26 |
Family
ID=15071640
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60132020A Granted JPS61294031A (en) | 1985-06-19 | 1985-06-19 | Oil-pressure circuit for excavator |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61294031A (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01102131A (en) * | 1987-10-16 | 1989-04-19 | Hitachi Constr Mach Co Ltd | Oil-pressure circuit for oil-pressure type excavator |
| JPH0226652U (en) * | 1988-08-09 | 1990-02-21 | ||
| JPH0728211Y2 (en) * | 1988-08-02 | 1995-06-28 | 株式会社小松製作所 | Hydraulic working machine |
| EP0381778A4 (en) * | 1988-08-02 | 1990-12-27 | Kabushiki Kaisha Komatsu Seisakusho | Moving speed regulator for hydraulically driven working machines |
| US6282890B1 (en) | 2000-01-21 | 2001-09-04 | Komatsu Ltd. | Hydraulic circuit for construction machines |
| JP5608252B2 (en) * | 2013-02-26 | 2014-10-15 | カヤバ工業株式会社 | Actuator |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5616736A (en) * | 1979-07-19 | 1981-02-18 | Kobe Steel Ltd | Hydraulic circuit for hydraulic power shovel |
| JPS5943567B2 (en) * | 1977-10-31 | 1984-10-23 | 大阪機工株式会社 | Pipe yarn extraction device in doffing machine of spinning machine or twisting machine |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6131083Y2 (en) * | 1981-05-27 | 1986-09-10 | ||
| JPS5943567U (en) * | 1982-09-08 | 1984-03-22 | 株式会社小松製作所 | Construction machinery hydraulic circuit |
-
1985
- 1985-06-19 JP JP60132020A patent/JPS61294031A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5943567B2 (en) * | 1977-10-31 | 1984-10-23 | 大阪機工株式会社 | Pipe yarn extraction device in doffing machine of spinning machine or twisting machine |
| JPS5616736A (en) * | 1979-07-19 | 1981-02-18 | Kobe Steel Ltd | Hydraulic circuit for hydraulic power shovel |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61294031A (en) | 1986-12-24 |
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