JPH0726592A - Oil pressure circuit structure of back hoe - Google Patents
Oil pressure circuit structure of back hoeInfo
- Publication number
- JPH0726592A JPH0726592A JP16763093A JP16763093A JPH0726592A JP H0726592 A JPH0726592 A JP H0726592A JP 16763093 A JP16763093 A JP 16763093A JP 16763093 A JP16763093 A JP 16763093A JP H0726592 A JPH0726592 A JP H0726592A
- Authority
- JP
- Japan
- Prior art keywords
- hydraulic
- control valve
- traveling
- mode
- control valves
- 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.)
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Links
Landscapes
- Operation Control Of Excavators (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、２個のポンプからの圧
油で左右の走行装置および全ての作業用アクチュエータ
を駆動するように構成したバックホウの油圧回路構造に
関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic circuit structure of a backhoe configured to drive left and right traveling devices and all working actuators with pressure oil from two pumps.
【０００２】[0002]
【従来の技術】２ポンプ駆動型バックホウの油圧回路と
しては、例えば実開平１−７５１６５号公報に示されて
いるように、一方の走行用の油圧モータの制御弁と複数
の作業用のアクチュエータの制御弁群とを含むブロック
に一方の油圧ポンプを接続するとともに、他方の走行用
の油圧モータの制御弁と複数の作業用のアクチュエータ
の制御弁群とを含むブロックに他方の油圧ポンプを接続
した構造が採用されており、各ブロックにおいて、各制
御弁を互いに並列に接続している。2. Description of the Related Art As a hydraulic circuit of a two-pump drive type backhoe, for example, as shown in Japanese Utility Model Laid-Open No. 1-75165, a control valve for one traveling hydraulic motor and a plurality of working actuators are used. One hydraulic pump was connected to the block including the control valve group, and the other hydraulic pump was connected to the block including the control valve of the other traveling hydraulic motor and the control valve group of the plurality of working actuators. A structure is adopted, and each control valve is connected in parallel to each other in each block.
【０００３】[0003]
【発明が解決しようとする課題】上記構成によると、左
右の走行油圧モータを作動させて直進する場合には、作
業用のアクチュエータを作動させることができないもの
となっていた。本発明は、このような点に着目してなさ
れたものであって、直進走行しながら作業用のアクチュ
エータを作動させることができるようにすることで作業
性を向上することにある。According to the above construction, when the left and right traveling hydraulic motors are operated to move straight, the working actuator cannot be operated. The present invention has been made in view of such a point, and is to improve workability by enabling an actuator for work to be operated while traveling straight ahead.
【０００４】[0004]
【課題を解決するための手段】本発明の特徴構成は、一
方の走行用の油圧モータの制御弁と複数の作業用のアク
チュエータの制御弁群とを含むブロックに一方の油圧ポ
ンプを接続するとともに、他方の走行用の油圧モータの
制御弁と複数の作業用のアクチュエータの制御弁群とを
含むブロックに他方の油圧ポンプを接続したバックホウ
の油圧回路構造であって、各ブロックにおいて、走行用
の油圧モータの制御弁と作業用のアクチュエータの制御
弁群とをそれぞれ並列接続し、各ブロックに各々の油圧
ポンプから独立的に圧油供給する第１モードと、両油圧
ポンプの圧油を合流して両ブロックを並列状態に接続す
る第２モードとに切換え可能な流路切換弁を設け、この
流路切換弁を、両油圧モータの制御弁を共に走行位置に
操作し、かつ、いずれかの作業用のアクチュエータの制
御弁を操作したたことに連動して、前記第１モードから
前記第２モードに切換え作動させるように構成してある
点にある。A feature of the present invention is that one hydraulic pump is connected to a block including a control valve for one traveling hydraulic motor and a control valve group for a plurality of working actuators. , A hydraulic circuit structure of a backhoe in which the other hydraulic pump is connected to a block including the control valve of the other traveling hydraulic motor and the control valve group of a plurality of working actuators, and in each block The control valve of the hydraulic motor and the control valve group of the work actuator are connected in parallel, respectively, and the first mode in which pressure oil is supplied to each block independently from each hydraulic pump and the pressure oil of both hydraulic pumps are merged. Is provided with a flow path switching valve that can be switched to a second mode in which both blocks are connected in parallel, and the flow path switching valve is operated by moving both control valves of both hydraulic motors to the traveling position. Re or in conjunction with that operates the control valve of the working of the actuator, from said first mode to a point that is configured to be switched operate in the second mode.
【０００５】[0005]
【作用】本発明の特徴構成によると、走行のみを行う時
や走行を停止しての作業時には流路切換弁は第１モード
にあり、一対の制御弁ブロックは夫々対応する油圧ポン
プからの圧油供給を独立的に受けて作動する。左右の走
行用の油圧モータを作動させるとともに、いずれかの作
業用アクチュエータを作動させる操作を行うと、流路切
換弁が第１モードから自動的に第２モードに切り換わ
り、全ての制御弁が並列の関係で２ポンプからの合流圧
油の供給を受ける状態となる。従って、左右の走行負荷
に差がない状態であれば、左右の油圧モータには合流圧
油の一部が均等に分配供給されるとともに、作業用のア
クチュエータにも合流圧油の一部が供給が行われて、直
進走行しながらの作業が可能となる。ただし、油圧モー
タへ供給される油量は、走行負荷および作業負荷のバラ
ンスによって変化する。According to the characteristic construction of the present invention, the flow path switching valve is in the first mode when the vehicle is traveling only or when the traveling is stopped, and the pair of control valve blocks are respectively provided with the pressures from the corresponding hydraulic pumps. Operates independently of oil supply. When the hydraulic motors for left and right traveling are operated and one of the work actuators is operated, the flow path switching valve automatically switches from the first mode to the second mode, and all control valves are operated. Due to the parallel relationship, the combined pressure oil is supplied from the two pumps. Therefore, if there is no difference between the left and right running loads, part of the combined pressure oil is evenly distributed and supplied to the left and right hydraulic motors, and part of the combined pressure oil is also supplied to the work actuators. By doing so, it becomes possible to work while traveling straight ahead. However, the amount of oil supplied to the hydraulic motor changes depending on the balance between the traveling load and the work load.
【０００６】[0006]
【発明の効果】従って、本発明によれば、通常の走行や
停止しての作業時には一対のブロックに属する油圧モー
タやアクチュエータを夫々独立的に駆動できながら、機
体を直進させながら各種作業作動を行うことが可能とな
って作業性が向上する。As described above, according to the present invention, during normal running or work while stopped, the hydraulic motors and actuators belonging to the pair of blocks can be independently driven, and various work operations can be performed while the machine body is moving straight. It becomes possible to perform and workability improves.
【０００７】[0007]
【実施例】図１に示すように、バックホウは、左右一対
のクローラ走行装置１およびドーザ２を備えた走行車体
３に旋回台４を全旋回可能に搭載し、この旋回台４にフ
ロント装置５、操縦部６、及び、原動部７を装備して構
成されている。前記フロント装置５は、ブーム８、アー
ム９およびバケッット１０を順次枢支連結してなり、ス
イングブラケット１１を介してフロント装置５全体を左
右にスイングできるように構成されている。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, in a backhoe, a swivel base 4 is mounted on a traveling vehicle body 3 provided with a pair of left and right crawler traveling devices 1 and a dozer 2 so that the swivel base 4 can be fully swiveled. The control section 6 and the driving section 7 are equipped. The front device 5 is formed by sequentially pivotally connecting a boom 8, an arm 9 and a bucket 10, and is configured to be able to swing the entire front device 5 left and right via a swing bracket 11.
【０００８】図２に、このバックホウの中立状態での油
圧回路が示されている。図において、Ｖ１，Ｖ２は走行
用油圧モータＭ１，Ｍ２の制御弁、Ｖ３は旋回用油圧モ
ータＭ３の制御弁、Ｖ４はブームシリンダＣ１の制御
弁、Ｖ５はアームシリンダＣ２の制御弁、Ｖ６はバケッ
トシリンダＣ３の制御弁、Ｖ７はスイングシリンダＣ４
の制御弁、Ｖ８はドーザシリンダＣ５の制御弁、Ｖ９は
油圧動力取り出し用の制御弁、Ｖ１０はパイロット操作
される流路切換弁であり、各種アクチュエータは一対の
油圧ポンプＰ１，Ｐ２からの圧油供給を受けて駆動され
る。FIG. 2 shows the hydraulic circuit in the neutral state of the backhoe. In the figure, V1 and V2 are control valves for the traveling hydraulic motors M1 and M2, V3 is a control valve for the swing hydraulic motor M3, V4 is a control valve for the boom cylinder C1, V5 is a control valve for the arm cylinder C2, and V6 is a bucket. Control valve for cylinder C3, V7 is swing cylinder C4
, V8 is a control valve for the dozer cylinder C5, V9 is a control valve for extracting hydraulic power, V10 is a pilot operated flow path switching valve, and various actuators are pressure oil from a pair of hydraulic pumps P1 and P2. Driven by supply.
【０００９】ここで、一方の走行用油圧モータＭ１の制
御弁Ｖ１、アームシリンダＣ２の制御弁Ｖ５、スイング
シリンダＣ４の制御弁Ｖ７、ドーザシリンダＣ５の制御
弁Ｖ８、および旋回用油圧モータＭ３の制御弁Ｖ３は一
方の油圧ポンプＰ１から並列的に圧油供給を受けるブロ
ックに構成され、他方の走行用油圧モータＭ２の制御弁
Ｖ２、ブームシリンダＣ１の制御弁Ｖ４およびバケット
シリンダＣ３の制御弁Ｖ６は他方の油圧ポンプＰ２から
並列的に圧油供給を受けるブロックに構成されている。
又、油圧動力取り出し用の制御弁Ｖ９のみが両油圧ポン
プＰ１，Ｐ２からの圧油が合流される圧油供給路ａから
圧油を受けるように構成されている。Control of the control valve V1 of the traveling hydraulic motor M1, the control valve V5 of the arm cylinder C2, the control valve V7 of the swing cylinder C4, the control valve V8 of the dozer cylinder C5, and the turning hydraulic motor M3. The valve V3 is configured as a block that receives pressure oil supply in parallel from one hydraulic pump P1, and the other control valve V2 of the traveling hydraulic motor M2, the control valve V4 of the boom cylinder C1 and the control valve V6 of the bucket cylinder C3 are The block is configured to receive pressure oil supply in parallel from the other hydraulic pump P2.
Further, only the control valve V9 for extracting hydraulic power is configured to receive the pressure oil from the pressure oil supply passage a where the pressure oils from the two hydraulic pumps P1 and P2 are merged.
【００１０】又、流路切換弁Ｖ１０のパイロット油路ｂ
は、各制御弁Ｖ１〜Ｖ９を介してタンクに連通されてお
り、常態ではパイロット圧がタンクに抜けている。そし
て、各制御弁Ｖ１〜Ｖ９の操作に基づいて以下のように
切換え作動する。Further, the pilot oil passage b of the passage switching valve V10
Are communicated with the tank through the control valves V1 to V9, and the pilot pressure is normally released to the tank. Then, based on the operation of each control valve V1 to V9, switching operation is performed as follows.
【００１１】（イ）走行 制御弁Ｖ１およびＶ２を操作して左右の走行用油圧モー
タＭ１，Ｍ２を作動させる走行状態では、パイロット油
路ｂに連通したドレン路ｂ1 およびｂ2 が遮断される
が、他のドレン路ｂ3 が制御弁Ｖ４，Ｖ６，Ｖ５，Ｖ
７，Ｖ８，Ｖ３を介してタンクに連通した状態にあるた
めに、パイロット油路ｂに圧の発生はなく、流路切換弁
Ｖ１０は図２中に示す位置に保持される。このように流
路切換弁Ｖ１０が切換え作動されない第１モードでは、
走行用油圧モータＭ１，Ｍ２にそれぞれ独立的に両油圧
ポンプＰ１，Ｐ２からの圧油が供給される。(A) In the traveling state in which the traveling control valves V1 and V2 are operated to operate the left and right traveling hydraulic motors M1 and M2, the drain passages b1 and b2 communicating with the pilot oil passage b are cut off. The other drain path b3 is the control valve V4, V6, V5, V
Since it is in communication with the tank via 7, V8 and V3, no pressure is generated in the pilot oil passage b, and the flow passage switching valve V10 is held at the position shown in FIG. In this way, in the first mode in which the flow path switching valve V10 is not switched,
The hydraulic oils from the two hydraulic pumps P1 and P2 are independently supplied to the traveling hydraulic motors M1 and M2.
【００１２】（ロ）機体停止しての作業 制御弁Ｖ１およびＶ２を中立に維持した機体停止状態で
作業用のアクチュエータ群の制御弁Ｖ３，Ｖ４，Ｖ５，
Ｖ６，Ｖ７，Ｖ８を操作すると、パイロット油路ｂに連
通したドレン路ｂ3 は閉じられるが、ドレン路ｂ1 およ
びｂ2 が制御弁Ｖ１およびＶ２を介してタンクに連通し
ているために、この場合もパイロット油路ｂに圧の発生
はなく、流路切換弁Ｖ１０は前記第１モードに維持され
る。(B) Work with the airframe stopped The control valves V3, V4, V5 of the actuator group for work with the airframe stopped while keeping the control valves V1 and V2 neutral.
When V6, V7 and V8 are operated, the drain passage b3 communicating with the pilot oil passage b is closed, but in this case as well, the drain passages b1 and b2 communicate with the tank via the control valves V1 and V2. No pressure is generated in the pilot oil passage b, and the flow path switching valve V10 is maintained in the first mode.
【００１３】（ハ）直進走行しながらの作業 図３に示すように、走行用油圧モータＭ１，Ｍ２の制御
弁Ｖ１，Ｖ２を操作して直進走行する状態で、作業用の
アクチュエータの制御弁（例えばアームシリンダＣ２の
制御弁Ｖ５）を操作すると、パイロット油路ｂに連通し
たドレン路ｂ1，ｂ2 およびｂ3 が全て閉じられて流路
切換弁Ｖ１０は図３中に示す位置に切換えられる。この
ように流路切換弁Ｖ１０が切換え作動された第２モード
では、両油圧ポンプＰ１，Ｐ２の圧油供給路が流路切換
弁Ｖ１０を介して連通され、その結果、全ての制御弁Ｖ
１〜Ｖ９が両油圧ポンプＰ１，Ｐ２に対して並列接続さ
れた関係となる。その結果、図３の場合、走行負荷が等
しいと両油圧ポンプＰ１，Ｐ２からの合流圧油の一部が
左右の走行用油圧モータＭ１，Ｍ２に等分配（場合）さ
れるとともに、合流圧油の一部がアームシリンダＣ２に
も供給され、直進走行しながらのアーム作動が行われ
る。尚、油圧モータＭ１，Ｍ２へ供給される油量は、走
行負荷および作業負荷のバランスによって定まる。(C) Work while traveling straight ahead As shown in FIG. 3, the control valve () of the working actuator is operated in a state where the control valves V1 and V2 of the traveling hydraulic motors M1 and M2 are operated to travel straight ahead. For example, when the control valve V5) of the arm cylinder C2 is operated, the drain passages b1, b2 and b3 communicating with the pilot oil passage b are all closed and the flow passage switching valve V10 is switched to the position shown in FIG. In the second mode in which the flow passage switching valve V10 is thus switched, the pressure oil supply passages of the two hydraulic pumps P1 and P2 are communicated with each other via the flow passage switching valve V10, and as a result, all control valves V
1 to V9 are connected in parallel to both hydraulic pumps P1 and P2. As a result, in the case of FIG. 3, when the traveling load is equal, part of the combined pressure oil from both hydraulic pumps P1 and P2 is equally distributed (case) to the left and right traveling hydraulic motors M1 and M2, and the combined pressure oil is Is partially supplied to the arm cylinder C2, and the arm is operated while traveling straight ahead. The amount of oil supplied to the hydraulic motors M1 and M2 is determined by the balance between the traveling load and the work load.
【００１４】〔別実施例〕前記各制御弁Ｖ１〜Ｖ９をパ
イロット制御弁や電磁制御弁に構成して実施することも
できる。又、制御弁操作系に操作状態を検知するスイッ
チ等のセンサーを設け、操作状態の検出結果に基づいて
電磁弁で構成した前記流路切換弁Ｖ１０を電気的に操作
する形態で実施することも可能である。[Other Embodiments] Each of the control valves V1 to V9 may be implemented as a pilot control valve or an electromagnetic control valve. Also, a sensor such as a switch for detecting an operating state may be provided in the control valve operating system, and the flow path switching valve V10 formed of an electromagnetic valve may be electrically operated based on the detection result of the operating state. It is possible.
【００１５】尚、特許請求の範囲の項に図面との対照を
便利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 reference numerals are given in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.
【図１】バックホウの全体側面図1] Overall side view of backhoe
【図２】中立状態を示す油圧回路図FIG. 2 is a hydraulic circuit diagram showing a neutral state.
【図３】直進走行で作業を行う状態を示す油圧回路図FIG. 3 is a hydraulic circuit diagram showing a state in which work is performed by traveling straight ahead.
Ｍ１，Ｍ２ 油圧モータ Ｐ１，Ｐ２ 油圧ポンプ Ｖ１，Ｖ２ 走行用油圧モータの制御弁 Ｖ３〜Ｖ８ 作業用アクチュエータの制御弁 Ｖ１０ 流路切換弁 M1, M2 hydraulic motors P1, P2 hydraulic pumps V1, V2 control valves for traveling hydraulic motors V3 to V8 control valves for working actuators V10 flow path switching valves
Claims (1)
御弁（Ｖ１）と複数の作業用のアクチュエータの制御弁
群とを含むブロックに一方の油圧ポンプ（Ｐ１）を接続
するとともに、他方の走行用の油圧モータ（Ｍ２）の制
御弁（Ｖ２）と複数の作業用のアクチュエータの制御弁
（Ｖ４，Ｖ６）群とを含むブロックに他方の油圧ポンプ
（Ｐ２）を接続したバックホウの油圧回路構造であっ
て、 各ブロックにおいて、走行用の油圧モータ（Ｍ１），
（Ｍ２）の制御弁（Ｖ１），（Ｖ２）と作業用のアクチ
ュエータの制御弁（Ｖ３，Ｖ５，Ｖ７，Ｖ８），（Ｖ
４，Ｖ６）群とをそれぞれ並列接続し、 各ブロックに各々の油圧ポンプ（Ｐ１），（Ｐ２）から
圧油供給する第１モードと、両油圧ポンプ（Ｐ１），
（Ｐ２）の圧油を合流して両ブロックを並列状態に接続
する第２モードとに切換え可能な流路切換弁（Ｖ１０）
を設け、 この流路切換弁（Ｖ１０）を、両油圧モータ（Ｍ１），
（Ｍ２）の制御弁（Ｖ１），（Ｖ２）を共に走行位置に
操作し、かつ、いずれかの作業用のアクチュエータの制
御弁を操作したことに連動して、前記第１モードから前
記第２モードに切換え作動させるように構成してあるこ
とを特徴とするバックホウの油圧回路構造。1. A hydraulic pump (P1) is connected to a block including a control valve (V1) of one traveling hydraulic motor (M1) and a control valve group of a plurality of working actuators, and the other is connected to the block. Hydraulic circuit of the backhoe in which the other hydraulic pump (P2) is connected to the block including the control valve (V2) of the traveling hydraulic motor (M2) and the control valve (V4, V6) group of the plurality of working actuators In each block, a hydraulic motor (M1) for traveling,
(M2) control valves (V1), (V2) and work actuator control valves (V3, V5, V7, V8), (V
4, V6) groups are connected in parallel, and the first mode in which pressure oil is supplied to each block from each hydraulic pump (P1), (P2) and both hydraulic pumps (P1),
A flow path switching valve (V10) capable of switching to a second mode in which the pressure oil of (P2) is joined and both blocks are connected in parallel.
And the flow path switching valve (V10) is connected to both hydraulic motors (M1),
From the first mode to the second mode in conjunction with operating both the control valves (V1) and (V2) of (M2) to the traveling position and operating the control valve of one of the working actuators. A hydraulic circuit structure for a backhoe, characterized in that the hydraulic circuit is configured so as to be switched to a mode.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16763093A JP2942102B2 (en) | 1993-07-07 | 1993-07-07 | Backhoe hydraulic circuit structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16763093A JP2942102B2 (en) | 1993-07-07 | 1993-07-07 | Backhoe hydraulic circuit structure |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0726592A true JPH0726592A (en) | 1995-01-27 |
| JP2942102B2 JP2942102B2 (en) | 1999-08-30 |
Family
ID=15853348
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16763093A Expired - Fee Related JP2942102B2 (en) | 1993-07-07 | 1993-07-07 | Backhoe hydraulic circuit structure |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2942102B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002276607A (en) * | 2001-03-19 | 2002-09-25 | Kayaba Ind Co Ltd | Hydraulic control device |
| WO2013183795A1 (en) * | 2012-06-04 | 2013-12-12 | 볼보 컨스트럭션 이큅먼트 에이비 | Driving control method for construction machine |
-
1993
- 1993-07-07 JP JP16763093A patent/JP2942102B2/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002276607A (en) * | 2001-03-19 | 2002-09-25 | Kayaba Ind Co Ltd | Hydraulic control device |
| JP4548959B2 (en) * | 2001-03-19 | 2010-09-22 | カヤバ工業株式会社 | Hydraulic control device |
| WO2013183795A1 (en) * | 2012-06-04 | 2013-12-12 | 볼보 컨스트럭션 이큅먼트 에이비 | Driving control method for construction machine |
| US9562345B2 (en) | 2012-06-04 | 2017-02-07 | Volvo Construction Equipment Ab | Driving control method for construction machine |
| DE112012006316B4 (en) | 2012-06-04 | 2023-07-06 | Volvo Construction Equipment Ab | Drive control method for a construction machine |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2942102B2 (en) | 1999-08-30 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |