JPH0637779B2 - Attachment hydraulic circuit - Google Patents
Attachment hydraulic circuitInfo
- Publication number
- JPH0637779B2 JPH0637779B2 JP6730488A JP6730488A JPH0637779B2 JP H0637779 B2 JPH0637779 B2 JP H0637779B2 JP 6730488 A JP6730488 A JP 6730488A JP 6730488 A JP6730488 A JP 6730488A JP H0637779 B2 JPH0637779 B2 JP H0637779B2
- Authority
- JP
- Japan
- Prior art keywords
- switching valve
- valve
- actuators
- circuit
- operated
- 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 - Fee Related
Links
- 238000010586 diagram Methods 0.000 description 3
- 230000007257 malfunction Effects 0.000 description 3
- 230000000694 effects Effects 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
-
- 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
- E02F9/2278—Hydraulic circuits
- E02F9/2285—Pilot-operated systems
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)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、油圧シヨベル等のアタツチメント油圧回路に
関する。Description: TECHNICAL FIELD The present invention relates to an attachment hydraulic circuit such as a hydraulic shovel.
従来、特殊アタツチメントを装備した油圧シヨベルは第
２図に示すものがある。この第２図において、油圧シヨ
ベル本体１には２ピースブームが備えられ、これらのブ
ームを操作するブームシリンダ２、アームシリンダ３、
及び分割したブームを連結し、第２ブームを操作するポ
ジシヨニングシリンダ６が備えられている。また、ブー
ムの先端にはクラムシエルバケツト７が備えられ、クラ
ムシエルバケツト開閉シリンダ４により開閉操作され、
また油圧モータ５により回転操作される。Conventionally, there is a hydraulic shovel equipped with a special attachment as shown in FIG. In FIG. 2, the hydraulic shovel main body 1 is provided with a two-piece boom, and a boom cylinder 2, an arm cylinder 3 for operating these booms,
Also provided is a positioning cylinder 6 for connecting the divided booms and operating the second boom. In addition, a clam shell bucket 7 is provided at the tip of the boom, and the clam shell bucket opening / closing cylinder 4 opens and closes the boom.
It is also rotated by the hydraulic motor 5.
この油圧シヨベルは標準仕様のアタツチメントに対して
アクチユエータの数が増えた場合、即ち、油圧モータ５
と、ポジシヨニングシリンダ６が付け加わる場合であ
り、このような２つのアクチユエータを１つの方向切換
弁を共有して操作する油圧回路は第３図に示すものがあ
る。この第３図において、２つのアクチユエータである
クラムシエル回転用油圧モータ５とポジシヨニングシリ
ンダ６は選択切換弁、例えば電磁弁１６に接続され、更
に１つの方向切換弁１３に接続されている。この方向切
換弁１３は複数備えられて方向切換弁の１ブロツク１２
が構成され、各方向切換弁１３にはメインポンプ１１が
接続されて油圧がかかるようになつている。前記方向切
換弁１３にはパイロツトバルブ１５が接続され、このパ
イロツトバルブ１５の操作によりパイロツトポンプ１４
の油圧が方向切換弁１３を切換えて油圧モータ５を正逆
回転させ、あるいはポジシヨニングシリンダ６を伸縮さ
せる。また、電磁弁１６はスイツチ１７のオン操作によ
りバネ７に抗して移動させて油圧は油圧モータ５に選択
切換され、また、電磁弁１６はオフ操作によりバネ７の
押圧力で移動されて油圧はポジシヨニングシリンダ６に
選択切換される。尚、８，９は方向切換弁13を中央位
置、即ち「断」状態に保持しようとするバネである。This hydraulic shovel uses the hydraulic motor 5 when the number of actuators is increased compared to the standard specification attachment.
And a case where the positioning cylinder 6 is added, and there is a hydraulic circuit shown in FIG. 3 for operating such two actuators sharing one directional control valve. In FIG. 3, two actuators, a hydraulic motor 5 for rotating the clam shell and a positioning cylinder 6, are connected to a selective switching valve, for example, a solenoid valve 16, and further connected to one directional switching valve 13. A plurality of the directional control valves 13 are provided and one block 12 of the directional control valves 12 is provided.
The main pump 11 is connected to each direction switching valve 13 to apply hydraulic pressure. A pilot valve 15 is connected to the direction switching valve 13, and the pilot pump 15 is operated by operating the pilot valve 15.
Oil pressure switches the directional control valve 13 to rotate the hydraulic motor 5 in the forward and reverse directions, or to expand and contract the positioning cylinder 6. Further, the solenoid valve 16 is moved against the spring 7 by the ON operation of the switch 17 so that the hydraulic pressure is selectively switched to the hydraulic motor 5, and the solenoid valve 16 is moved by the pressing force of the spring 7 by the OFF operation and the hydraulic pressure is changed. Is selectively switched to the positioning cylinder 6. Reference numerals 8 and 9 are springs for holding the directional control valve 13 in the central position, that is, in the "off" state.
ところで、上記したように、従来では１つの方向切換弁
１３に２つのアクチユエータを電磁弁16を介して接続
し、この電磁弁１６をスイツチ操作にて選択切換するこ
とにより１つの操作レバーあるいはペダルで１つのパイ
ロツトバルブ１５が操作されて２つのアクチユエータを
選択操作している。したがつて、この装置では、操作す
るアクチユエータを変える時には、必ずスイツチを操作
してアクチユエータの選択を行なうため、この切換操作
がわずらわしく、かつ今まで、どのアクチユエータを選
択していたかを確認する必要があり、誤動作が起こる可
能性が大であるという問題があつた。By the way, as described above, conventionally, two actuators are connected to one direction switching valve 13 via the solenoid valve 16, and the solenoid valve 16 is selectively switched by a switch operation so that one operating lever or pedal is used. One pilot valve 15 is operated to selectively operate two actuators. Therefore, in this device, when changing the actuator to be operated, the switch is always operated to select the actuator, so this switching operation is troublesome and it is necessary to confirm which actuator has been selected until now. However, there is a possibility that malfunction may occur.
そこで、本発明は上記した従来技術の問題点を解消する
ためになされたもので、その目的は、複数のアクチユエ
ータを切換操作することなく、自動的に切換えられ、操
作が簡単で、誤動作が妨げ安全に作業できるアタツチメ
ント油圧回路を提供するものである。Therefore, the present invention has been made in order to solve the above-mentioned problems of the prior art, and its purpose is to automatically switch without switching operation of a plurality of actuators, easy operation, and prevent malfunction. It is intended to provide an attachment hydraulic circuit capable of safely working.
上記した目的を達成するために、本発明は、複数のアク
チユエータと、該アクチユエータを作動する１つの方向
切換弁と、該方向切換弁と前記アクチユエータとの間に
介在され、作動すべき前記アクチユエータを選択して前
記方向切換弁を前記アクチユエータの１つと通じさせる
選択切換弁と、前記アクチユエータ毎に別個に設けられ
た操作回路と、該操作回路の複数同時操作時、複数のア
クチユエータのいずれかを優先させる優先回路と、非作
動状態のアクチユエータに対応する操作回路の操作によ
つて生じる信号により前記選択切換弁を切換え、その後
該信号により前記方向切換弁を操作するように動作する
制御回路とを備えた構成にしてある。In order to achieve the above-mentioned object, the present invention provides a plurality of actuators, a directional switching valve that operates the actuators, and an actuator that is interposed between the directional switching valve and the actuator and that should be operated. A selection switching valve that selectively communicates the directional switching valve with one of the actuators, an operation circuit separately provided for each actuator, and when a plurality of the operation circuits are simultaneously operated, one of the actuators has priority. And a control circuit that operates so as to operate the directional switching valve by a signal generated by the operation of the operating circuit corresponding to the inactive actuator, and then operates the directional switching valve by the signal. It has a different structure.
〔作用〕 操作回路を操作すると、その信号圧により選択切換弁が
切換えられて、対応するアクチユエータと方向切換弁と
が接続されてアクチユエータが作動される。また、信号
圧は制御回路により、選択切換弁の方を方向切換弁より
先に作動するので、操作しようとするアクチユエータが
確実に操作される。また、操作回路を複数同時操作時に
アクチユエータの１つを優先される優先回路が備えられ
ていることにより、複数信号による操作系の混乱が生じ
ることがなく、安全性の低下はない。[Operation] When the operation circuit is operated, the selection switching valve is switched by the signal pressure, the corresponding actuator and the direction switching valve are connected, and the actuator is operated. Further, since the control circuit operates the selection switching valve before the direction switching valve for the signal pressure, the actuator to be operated is reliably operated. Further, since the priority circuit that prioritizes one of the actuators is provided when a plurality of operation circuits are simultaneously operated, the operation system is not confused by a plurality of signals, and the safety is not deteriorated.
以下、本発明の実施例を図面によつて説明する。 Embodiments of the present invention will be described below with reference to the drawings.
第１図は本発明によるアタツチメント回路の一実施例を
示す回路図である。FIG. 1 is a circuit diagram showing an embodiment of an attachment circuit according to the present invention.
この第１図において、クラムシエル回転用油圧モータ５
とポジシヨニングシリンダ６は選択切換弁２２を介して
１つの方向切換弁１３に接続されている。この方向切換
弁１３は更に複数配設された方向切換弁とともに方向切
換弁の１ブロツク12を構成し、また各方向切換弁13はメ
インポンプ11が接続されている。また、選択切換弁２２
は後述するパイロツトバルブの操作により発生する信号
圧により作動して方向切換弁１３が油圧モータ５、もし
くはポジシヨニングシリンダ６のいずれかと接続するよ
うに切換えるようになつている。２５は選択切換弁２２
が通常ポジシヨニングシリンダ６と接続されるように押
圧するバネである。また、方向切換弁１３には、油圧モ
ータ５とポジシヨニングシリンダ６に対応してそれぞれ
を操作する操作回路、例えばパイロツトバルブ１５，２
１が接続されている。このパイロツトバルブ１５は切換
弁２３，２３を介して方向切換弁１３に接続され、パイ
ロツトバルブ１５を操作することによりパイロツトポン
プ１４の信号圧が方向切換弁１３に伝わり右もしくは左
方向に移動され、ポジシヨニングシリンダ６を伸縮させ
る。また、パイロツトバルブ２１は制御回路、例えば絞
り２４，２４を介して方向切換弁１３に接続されて油圧
モータ５を正逆回転させるとともに、油圧パイプは分岐
されて選択切換弁２２に接続されバネ２５に抗して移動
し油圧モータ５の方に切換えるようになつている。この
絞り２４，２４によつて方向切換弁１２より先に選択切
換弁２２を操作される。更に、パイロツトバルブ２１の
油圧パイプは分岐されて前記切換弁２３，２３にそれぞ
れ接続され、パイロツトバルブ２１を操作した時に切換
弁２３，２３をバネ２８，２８に抗して移動してパイロ
ツトバルブ１５の油圧パイプを遮断し、パイロツトバル
ブ２１の操作が優先するようになつており、これらによ
つて優先回路が構成されている。In FIG. 1, the hydraulic motor 5 for rotating the clam shell
And the positioning cylinder 6 is connected to one direction switching valve 13 via a selection switching valve 22. This directional control valve 13 constitutes one block 12 of the directional control valve together with a plurality of directional control valves, and the main pump 11 is connected to each directional control valve 13. In addition, the selection switching valve 22
Is operated by a signal pressure generated by the operation of a pilot valve, which will be described later, so that the direction switching valve 13 is switched to be connected to either the hydraulic motor 5 or the positioning cylinder 6. 25 is a selection switching valve 22
Is a spring which normally presses the positive cylinder 6 so as to connect it. Further, the direction switching valve 13 is provided with an operation circuit for operating the hydraulic motor 5 and the positioning cylinder 6, respectively, such as pilot valves 15 and 2.
1 is connected. This pilot valve 15 is connected to the direction switching valve 13 via the switching valves 23, 23, and by operating the pilot valve 15, the signal pressure of the pilot pump 14 is transmitted to the direction switching valve 13 and moved to the right or left, The positioning cylinder 6 is expanded and contracted. Further, the pilot valve 21 is connected to the direction switching valve 13 via a control circuit, for example, the throttles 24, 24 to rotate the hydraulic motor 5 forward and backward, and the hydraulic pipe is branched to be connected to the selection switching valve 22 and the spring 25. The hydraulic motor 5 is moved against this and is switched to the hydraulic motor 5. The selection switching valve 22 is operated by the throttles 24, 24 before the direction switching valve 12. Further, the hydraulic pipes of the pilot valve 21 are branched and connected to the switching valves 23, 23, respectively, and when the pilot valve 21 is operated, the switching valves 23, 23 are moved against the springs 28, 28 to move the pilot valve 15. The hydraulic pipe is cut off to prioritize the operation of the pilot valve 21, which constitutes a priority circuit.
尚、２６，２７は方向切換弁１３を断状態に付勢するバ
ネである。Numerals 26 and 27 are springs for urging the directional control valve 13 in the disconnection state.
このように構成された上記実施例の動作は、次のとおり
である。The operation of the above-described embodiment configured as described above is as follows.
第３図に示すように、選択切換弁２２はバネ２５によつ
て付勢された比較的使用頻度の高いアクチユエータであ
るポジシヨニングシリンダ６と方向切換弁１３が接続さ
れるようになつている。ここで、このポジシヨニングシ
リンダ６を操作する場合、パイロツトバルブ１５を操作
してパイロツトポンプ１４の油圧を信号圧として方向切
換弁１３に与え、右もしくは左方向に移動してメインポ
ンプ11からの方向を切換えることによりポジシヨニング
シリンダ６を伸縮させる。この時、切換弁２３，２３は
バネ２８，２８により開状態に保持されている。As shown in FIG. 3, the selection switching valve 22 is configured such that the direction switching valve 13 is connected to the positive cylinder 6 which is an actuator which is urged by a spring 25 and which is relatively frequently used. . Here, when operating this positioning cylinder 6, the pilot valve 15 is operated to apply the hydraulic pressure of the pilot pump 14 as a signal pressure to the directional control valve 13, and it is moved to the right or left to move from the main pump 11. The positive cylinder 6 is expanded and contracted by switching the direction. At this time, the switching valves 23, 23 are held in the open state by the springs 28, 28.
次に、油圧モータ５を操作する場合、パイロツトバルブ
２１を操作してパイロツトポンプ１４の油圧を信号圧と
して選択切換弁２２と方向切換弁１３に与えられる。こ
の時、パイロツトバルブ２１と方向切換弁１３との間に
介在された絞り２４，２４によつて信号圧は選択切換弁
２２に先に伝えられ、選択切換弁２２をバネ２５に抗し
て移動させ方向切換弁１３を油圧モータ５と接続され
る。次に、信号圧は方向切換弁１３に伝えられて方向切
換弁１３を右もしくは左方向へ移動し、油圧モータ５を
正逆回転させる。また、信号圧は切換弁２３，２３にも
伝えられ、この切換弁２３，２３をバネ２８に抗して開
状態か断状態に切換える。これにより、両パイロツトバ
ルブ１５，２１を同時に操作した場合、パイロツトバル
ブ２１の信号圧が優先して方向切換弁１３に伝えられ、
油圧モータ５が優先して操作されるようになつている。Next, when operating the hydraulic motor 5, the pilot valve 21 is operated to supply the hydraulic pressure of the pilot pump 14 to the selection switching valve 22 and the direction switching valve 13 as a signal pressure. At this time, the signal pressure is first transmitted to the selection switching valve 22 by the throttles 24, 24 interposed between the pilot valve 21 and the direction switching valve 13, and the selection switching valve 22 is moved against the spring 25. Then, the direction switching valve 13 is connected to the hydraulic motor 5. Next, the signal pressure is transmitted to the directional control valve 13 to move the directional control valve 13 to the right or left to rotate the hydraulic motor 5 forward and backward. Further, the signal pressure is also transmitted to the switching valves 23, 23, and the switching valves 23, 23 are switched between the open state and the disconnected state against the spring 28. As a result, when both pilot valves 15 and 21 are simultaneously operated, the signal pressure of the pilot valve 21 is transmitted to the direction switching valve 13 with priority.
The hydraulic motor 5 is preferentially operated.
このように構成された上記実施例にあつては、複数のア
クチユエータである油圧モータ５とポジシヨニングシリ
ンダ６に対応するパイロツトバルブ１５，２１を操作す
ることにより、選択切換弁２２が自動的に切換えられる
ので、従来の如くスイツチ操作が必要なく、操作が簡単
になるとともに、切換ミスによる誤動作を妨げ安全に作
業ができる。In the above-described embodiment having such a configuration, the selection switching valve 22 is automatically operated by operating the pilot valves 15 and 21 corresponding to the hydraulic motors 5 and the positioning cylinders 6 which are a plurality of actuators. Since switching is possible, there is no need for a switch operation as in the prior art, and the operation is simple, and erroneous operation due to switching mistakes is prevented and safe work can be performed.
尚、上記実施例にあつては、制御回路として絞り２４を
使用しているが、本発明はこれに限られるものでなく、
例えば、パイピング自体の管路抵抗による絞り作用によ
つてもよい。Although the diaphragm 24 is used as the control circuit in the above embodiment, the present invention is not limited to this.
For example, it may be based on the throttling action due to the conduit resistance of the piping itself.
以上説明したように、本発明は、操作回路を操作するこ
とにより、自動的に選択切換弁が切換わり、方向切換弁
が作動されるので、従来の如くスイツチ操作を必要とせ
ず、操作が簡単であり、切換ミスによる誤動作を妨げ安
全に作業ができる。As described above, according to the present invention, by operating the operation circuit, the selection switching valve is automatically switched and the directional switching valve is actuated, so that the switch operation is not required as in the conventional case, and the operation is simple As a result, a malfunction due to a switching error can be prevented and work can be performed safely.
第１図は本発明によるアタツチメント油圧回路の一実施
例を示す回路図、第２図は従来の特殊アタツチメント付
油圧シヨベルの側面図、第３図は従来の油圧シヨベルの
アタツチメント油圧回路を示す回路図である。 ５……油圧ポンプ、６……ポジシヨニングシリンダ、１
１……メインポンプ、１３……方向切換弁、１４……パ
イロツトポンプ、１５，２１……パイロツトバルブ、２
２……選択切換弁、２３……切換弁、２４……絞り、２
５，２６，２７，28……バネ。FIG. 1 is a circuit diagram showing an embodiment of an attachment hydraulic circuit according to the present invention, FIG. 2 is a side view of a conventional hydraulic shovel with a special attachment, and FIG. 3 is a circuit diagram showing an attachment hydraulic circuit of a conventional hydraulic shovel. Is. 5 ... hydraulic pump, 6 ... positioning cylinder, 1
1 ... Main pump, 13 ... Direction switching valve, 14 ... Pilot pump, 15, 21 ... Pilot valve, 2
2 ... selection switching valve, 23 ... switching valve, 24 ... throttle, 2
5,26,27,28 ... Springs.
Claims (1)
ユエータを作動する１つの方向切換弁と、該方向切換弁
と前記アクチユエータとの間に介在され、作動すべき前
記アクチユエータを選択して前記方向切換弁を前記アク
チユエータの１つと通じさせる選択切換弁と、前記各ア
クチユエータ毎に別個に設けられた操作回路と、該操作
回路の複数同時操作時、複数のアクチユエータのいずれ
かを優先させる優先回路と、非作動状態のアクチユエー
タに対応する操作回路の操作によつて生じる信号により
前記選択切換弁を切換え、その後該信号により前記方向
切換弁を操作するように動作する制御回路とを備えたこ
とを特徴とするアタツチメント油圧回路。1. A plurality of actuators, a directional switching valve for operating the plurality of actuators, and a directional switching valve that is interposed between the directional switching valve and the actuator and selects the actuator to be operated. A selection switching valve that communicates a valve with one of the actuators, an operation circuit separately provided for each of the actuators, and a priority circuit that prioritizes one of the actuators when a plurality of the operation circuits are simultaneously operated, And a control circuit which operates so as to operate the directional switching valve by a signal generated by the operation of the operating circuit corresponding to the inactive actuator, and which switches the selective switching valve by the signal. Attaching hydraulic circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6730488A JPH0637779B2 (en) | 1988-03-23 | 1988-03-23 | Attachment hydraulic circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6730488A JPH0637779B2 (en) | 1988-03-23 | 1988-03-23 | Attachment hydraulic circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01244025A JPH01244025A (en) | 1989-09-28 |
| JPH0637779B2 true JPH0637779B2 (en) | 1994-05-18 |
Family
ID=13341135
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6730488A Expired - Fee Related JPH0637779B2 (en) | 1988-03-23 | 1988-03-23 | Attachment hydraulic circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0637779B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3225753A1 (en) | 2016-04-01 | 2017-10-04 | Yanmar Co., Ltd. | Hydraulic circuit of hydraulic work vehicle |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107476362B (en) * | 2017-08-04 | 2020-06-02 | 上海大学 | A tunnel excavation device |
| CN108999819B (en) * | 2018-10-09 | 2024-11-22 | 广西玉柴装备科技有限公司 | A hydraulic auxiliary function expansion device |
-
1988
- 1988-03-23 JP JP6730488A patent/JPH0637779B2/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3225753A1 (en) | 2016-04-01 | 2017-10-04 | Yanmar Co., Ltd. | Hydraulic circuit of hydraulic work vehicle |
| JP2017187076A (en) * | 2016-04-01 | 2017-10-12 | ヤンマー株式会社 | Hydraulic circuit of hydraulic work machine |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01244025A (en) | 1989-09-28 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |