JPH02240334A - Circuit of hydrostatic power transmission device for working vehicle - Google Patents

Circuit of hydrostatic power transmission device for working vehicle

Info

Publication number
JPH02240334A
JPH02240334A JP6187189A JP6187189A JPH02240334A JP H02240334 A JPH02240334 A JP H02240334A JP 6187189 A JP6187189 A JP 6187189A JP 6187189 A JP6187189 A JP 6187189A JP H02240334 A JPH02240334 A JP H02240334A
Authority
JP
Japan
Prior art keywords
valve
oil passage
circuit
traveling
switching 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.)
Granted
Application number
JP6187189A
Other languages
Japanese (ja)
Other versions
JP2775461B2 (en
Inventor
Hiroshi Taji
浩 田路
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kobelco Construction Machinery Co Ltd
Original Assignee
Yutani Heavy Industries Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Yutani Heavy Industries Ltd filed Critical Yutani Heavy Industries Ltd
Priority to JP1061871A priority Critical patent/JP2775461B2/en
Publication of JPH02240334A publication Critical patent/JPH02240334A/en
Application granted granted Critical
Publication of JP2775461B2 publication Critical patent/JP2775461B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/16Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
    • F15B11/161Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors with sensing of servomotor demand or load
    • F15B11/162Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors with sensing of servomotor demand or load for giving priority to particular servomotors or users
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/16Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
    • F15B11/17Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors using two or more pumps

Abstract

PURPOSE:To contrive to improve performance of a working machine by providing a pilot selector valve and an unloader valve to a forward-flow-side oil passage, and by regulating a hydraulic motor for traveling by the use of the unloader valve, with the selector valve operated by a signal sent to a hydraulic actuator for the working machine. CONSTITUTION:A pilot selector valve 19 and an unload valve 22 that is controlled by the selector valve 19 are provided to a forward-flow-side oil passage 17, and changeover operation of the pilot selector valve 19 is actuated by a signal from actuating pressure acting on a bucket cylinder 6. Function of the selector valve 19 regulates the pressure of pressurized oil to be supplied to a hydraulic motor 16 for traveling by operation of the unload valve 22. When heavy load is applied to the bucket at scoop-up work of a wheel loader, the pressure of the pressurized oil applied to the motor 16 decreases, resulting in decrease of absorption torque at a hydrostatic power transmission device circuit 10'. Thereby the circuit is made to give priority to the scoop-up power of the bucket, and the working machine can develop performance preferring work to the traveling.

Description

【発明の詳細な説明】 産業上の利用分野 この発明は、ホイールローダなと作業車両の走行用油圧
伝動装置回路に関する。
DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a hydraulic transmission circuit for running a working vehicle such as a wheel loader.

従来の技術 第2図は、ホイールローダ1の側面図である。Conventional technology FIG. 2 is a side view of the wheel loader 1.

図において、2はホイールローダ1の車体、3はブーム
、4はブームシリンダ、5はクロスリンク6はパケット
シリンダ、7はパケット、8はパケットリンクである。
In the figure, 2 is a body of a wheel loader 1, 3 is a boom, 4 is a boom cylinder, 5 is a cross link 6 is a packet cylinder, 7 is a packet, and 8 is a packet link.

ホイールローダ1では、ブーム3を車体2にブームシリ
ンダ4により回動可能に設け、クロスリンク5をブーム
3に枢支し、パケットシリンダ6をクロスリンク5の上
端と車体2との間に設けている。そしてパケット7をブ
ーム3先端部に枢着し、かつパケット7とクロスリンク
5下端とをパケットリンク8を介して連結しブームシリ
ンダ4およびパケットシリンダ6の伸縮作動によりパケ
ット7を持上げまたは掘削傾動可能としている。そして
ホイールローダ1が土質など掘削対称物イの掘削作業を
行うときには、矢印口で示す前進方向のけん引力と、矢
印ハで示す掘起し力と、矢印二で示す持上げ力をはたら
かせて作業を行うようにしている。第3図は、良好な掘
削性能を示すパケット操作時のけん引カー堀起し力線図
である。掘起し力はけん引力に対してはぼ比例関係にあ
り、その掘削性能曲線は直線状を示すとともにその曲線
の傾斜角度θは、一般的には45″位が良いとされてい
る。また、ホイールローダ1が掘削対象物イにパケット
7を突込み、そのパケット7を上方へ掘起すと、パケッ
ト7に大きな負荷がかかりエンジン回転数が低下する。
In the wheel loader 1, a boom 3 is rotatably provided on the vehicle body 2 by a boom cylinder 4, a cross link 5 is pivotally supported on the boom 3, and a packet cylinder 6 is provided between the upper end of the cross link 5 and the vehicle body 2. There is. Then, the packet 7 is pivotally attached to the tip of the boom 3, and the packet 7 and the lower end of the cross link 5 are connected via the packet link 8, so that the packet 7 can be lifted or excavated by the telescopic operation of the boom cylinder 4 and the packet cylinder 6. It is said that When the wheel loader 1 performs excavation work on the object to be excavated (A), such as soil quality, the work is performed by exerting a traction force in the forward direction shown by the arrowhead, an excavation force shown by the arrow C, and a lifting force shown by the arrow 2. I try to do it. FIG. 3 is a towing car excavation force diagram during packet operation showing good excavation performance. The digging force is approximately proportional to the traction force, and the digging performance curve shows a straight line, and the inclination angle θ of the curve is generally considered to be about 45''. When the wheel loader 1 thrusts the packet 7 into the excavated object A and excavates the packet 7 upward, a large load is applied to the packet 7 and the engine speed decreases.

この場合にホイールローダが因みにトルコン式車両であ
れば、上記エンジンからトルコンが吸収するトルクが減
少するので、必然的に前進方向のけん引力も低下する。
In this case, if the wheel loader is a torque converter type vehicle, the torque absorbed by the torque converter from the engine is reduced, so the traction force in the forward direction is inevitably reduced.

したがって上記けん引力の低下にともない、パケット7
をダンプさせようとする反力も低減し、良い掘削性能を
得ることができる。第4図は、ホイールローダの前進掘
起し時におけるエンジン回転数−吸収トルク曲線図であ
る図において、曲線aが、トルコン式車両の場合のエン
ジン用吸収トルク曲線である。
Therefore, as the above-mentioned traction force decreases, packet 7
The reaction force that tries to dump the material is also reduced, and good digging performance can be obtained. FIG. 4 is an engine rotation speed-absorption torque curve diagram during forward excavation of the wheel loader, in which curve a is the engine absorption torque curve in the case of a torque converter type vehicle.

第5図は、作業機用駆動回路9と走行用油圧伝動装置回
路10とをそなえた従来技術ホイールローダの油圧回路
図である。図において、11はエンジン、12は作業機
用油圧ポンプ、13はブームシリンダ4用制御弁、14
はパケットシリンダ6用制御弁、15は可変ポンプ、1
6は走行用油圧モータ、17は前進流れ側油路、18は
後進流れ側油路である。
FIG. 5 is a hydraulic circuit diagram of a conventional wheel loader equipped with a working machine drive circuit 9 and a travel hydraulic transmission circuit 10. In the figure, 11 is an engine, 12 is a hydraulic pump for work equipment, 13 is a control valve for boom cylinder 4, and 14
is a control valve for packet cylinder 6, 15 is a variable pump, 1
Reference numeral 6 indicates a hydraulic motor for traveling, 17 indicates a forward flow side oil passage, and 18 indicates a reverse flow side oil passage.

次に、従来技術回路の構成および作用機能を第5図につ
いて述べる。作業機用駆動回路9では、作業機用油圧ポ
ンプ12からの圧油を制御弁13゜14を介して、作業
機用油圧アクチュエータであるブ′−ムシリンダ4.パ
ケットシリンダ6へそれぞれ供給できるようにしている
。また走行用油圧伝動装置回路10では、可変ポンプ1
5と。その可変ポンプ15からの圧油により駆動される
走行用油圧モータ16と、上記可変ポンプ15と走行用
油圧モータ16とを相互に連通ずる前進流れ側油路17
および後進流れ側油路18とから、回路が構成されてい
る。それでホイールローダが前進走行を行うときには、
可変ポンプ15から前進流れ側油路17を通じて、油圧
モータ16に圧油が供給され、その油圧モータ16より
後進流れ側油路18を経て、圧油が可変ポンプ1.5に
戻されるホイールローダが後進走行を行うときには、可
変ポンプ15からの圧油が、上記前進走行の場合と逆の
方向に送油される。
Next, the configuration and function of the prior art circuit will be described with reference to FIG. In the work machine drive circuit 9, pressure oil from the work machine hydraulic pump 12 is supplied to a boom cylinder 4. It is possible to supply each to the packet cylinder 6. In addition, in the travel hydraulic transmission circuit 10, the variable pump 1
5 and. A traveling hydraulic motor 16 driven by pressure oil from the variable pump 15 and a forward flow side oil passage 17 that communicates the variable pump 15 and the traveling hydraulic motor 16 with each other.
A circuit is constituted by the flow-side oil passage 18 and the reverse flow side oil passage 18. So when the wheel loader moves forward,
The wheel loader is such that pressure oil is supplied from the variable pump 15 to the hydraulic motor 16 through the forward flow side oil passage 17, and from the hydraulic motor 16, the pressure oil is returned to the variable pump 1.5 through the reverse flow side oil passage 18. When traveling backwards, the pressure oil from the variable pump 15 is sent in the opposite direction to that for forward traveling.

発明が解決しようとする課題 作業機用駆動回路と走行用油圧伝動装置回路とをそなえ
た従来技術作業車両では、トルコン式車両の場合と異な
り、作業機たとえばパケットに大きな負荷が作用したと
きエンジン回転数が変化した(実際には可変ポンプの馬
力制御によりエンジン回転数は余り変化しない)として
も、その吸収トルクは殆ど変化しない。第4図における
曲線すが、油圧伝動装置回路のエンジン用吸収トルク曲
線である。そのためにエンジントルクはけん引力優先の
掘削性能となり、パケットの掘起し操作が困難になって
いた。
Problem to be Solved by the Invention In conventional work vehicles equipped with a drive circuit for a work machine and a hydraulic transmission circuit for traveling, unlike the case of a torque converter type vehicle, when a large load is applied to a work machine, for example, a packet, the engine rotation Even if the number changes (actually, the engine speed does not change much due to horsepower control of the variable pump), the absorbed torque hardly changes. The curve in FIG. 4 is an engine absorption torque curve of the hydraulic transmission circuit. For this reason, engine torque prioritizes traction power for excavation performance, making it difficult to excavate packets.

この発明は上記の課題を解決し、作業機たとえばパケッ
トを操作したとき油圧伝動装置回路の吸収トルクを低減
せしめ、パケット駆動馬力優先の作業車両用油圧伝動装
置回路を提供することを目的とする。
SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide a hydraulic transmission circuit for a working vehicle that gives priority to packet drive horsepower by reducing the absorbed torque of the hydraulic transmission circuit when operating a working machine, such as a packet.

課題を解決するための手段 上記の課題を解決するために講じたこの発明の手段は、 イ、走行用油圧伝動装置回路の前進流れ側油路にパイロ
ット切換弁と、そのパイロット切換弁により制御される
アンロードバルブを設け、口、さらに作業機用油圧アク
チュエータに作用する作動圧からの信号により上記パイ
ロット切換弁を切換作動するようにし、 ハ、上記ロ項におけるパイロット切換弁の切換作動によ
り、走行用油圧モータに供給される圧油圧力を上記アン
ロードバルブを介して調整するようにして、構成した。
Means for Solving the Problems The means of the present invention taken to solve the above problems are as follows: (a) A pilot switching valve is provided in the forward flow side oil passage of the traveling hydraulic transmission circuit, and the pilot switching valve is controlled by the pilot switching valve. An unload valve is provided, and the pilot switching valve is switched by a signal from the operating pressure acting on the hydraulic actuator for the work equipment. The hydraulic pressure supplied to the hydraulic motor is adjusted via the unload valve.

作      用 イ9作業機用油圧アクチュエータを作動させたときに、
その作動圧からの信号によりパイロット切換弁は遮断油
路位置よりアンロードバルブ用作用油圧位置に切換わる
。それによりアンロードバルブは作動するので、前進流
れ側油路内の圧油の一部は、可変ポンプや油タンクに戻
される。
Function A9: When the hydraulic actuator for work equipment is operated,
A signal from the operating pressure causes the pilot switching valve to switch from the cut-off oil path position to the unload valve working oil pressure position. As a result, the unload valve is actuated, so that a portion of the pressure oil in the forward flow side oil passage is returned to the variable pump or oil tank.

ロ、上記イ項のように作業機用油圧アクチュエータを作
動させたとき前進流れ側油路内の油圧が低下するので、
走行用油圧伝動装置回路の吸収トルクを低減させること
ができる。
B. When operating the hydraulic actuator for work equipment as in item A above, the oil pressure in the forward flow side oil passage decreases, so
The absorption torque of the travel hydraulic transmission circuit can be reduced.

実   施   例 以下、この発明の実施例を図面に基づいて詳細に説明す
る。第1図は、この発明にかかる油圧伝動装置回路図で
ある。図において、従来技術と同一構成要素を使用する
ものに対しては同符号を付す。10′は走行用油圧伝動
装置回路、1つはノ(イロット切換弁、20はパイロッ
ト切換弁19のパイロット圧受圧部、21はパイロ・ン
ト圧調整設定機能、22はアンロードバルブ、23はア
ンロードバルブ22のアンロード圧調整設定機能、24
はパイロットボート、25はパケットシリンダ6用作動
回路である。
Embodiments Hereinafter, embodiments of the present invention will be described in detail based on the drawings. FIG. 1 is a circuit diagram of a hydraulic transmission device according to the present invention. In the figure, the same reference numerals are given to the same components as in the prior art. 10' is a travel hydraulic transmission circuit, one is a pilot switching valve, 20 is a pilot pressure receiving part of the pilot switching valve 19, 21 is a pilot pressure adjustment setting function, 22 is an unload valve, and 23 is an unload valve. Unload pressure adjustment setting function of load valve 22, 24
25 is a pilot boat, and 25 is an operating circuit for the packet cylinder 6.

次に、この発明にかかる油圧伝動装置回路10’の構成
を第1図について述べる。前進流れ側油路17にパイロ
ット切換弁1つと、そのパイロ・ント切換弁19により
制御されるアンロートノ〈ルブ22を設けた。さらに、
パケットシリンダ6に作用する作動圧からの信号により
上記パイロット切換弁19を切換作動するようにした。
Next, the configuration of the hydraulic transmission circuit 10' according to the present invention will be described with reference to FIG. One pilot switching valve and an unloading valve 22 controlled by the pilot switching valve 19 are provided in the forward flow side oil passage 17. moreover,
The pilot switching valve 19 is switched by a signal from the operating pressure acting on the packet cylinder 6.

そしてパイロット切換弁19の切換作動により、走行用
油圧モータ16に供給される圧油圧力を上記アンロード
バルブ22を介して調整できるように構成した。
The hydraulic pressure supplied to the traveling hydraulic motor 16 can be adjusted via the unload valve 22 by switching the pilot switching valve 19.

次に、この発明にかかる油圧伝動装置回路10′の作用
機能について述べる。ホイールローダのパケットシリン
ダ6を作動させたときに、作動回路25における作動圧
は、油rI@26を通じて、パイロット切換弁1つのパ
イロット圧受圧部20に作用する。それで、パイロット
切換弁1つが遮断油路位置ホより作用油路位置へに切換
作動したときには、前進流れ側油路17内の圧油の一部
は、油路27.28、パイロット切換弁19の作用油路
位置へに流入し、そこで作用油路位置へ内の絞り部2つ
を通じ、一方は通路39、油路30を経てアンロードバ
ルブ22のパイロットボート24に作用する。アンロー
ドバルブ22が作動した場合には、前進流れ側油路17
内の圧油の一部は、油路27.31、アンロードバルブ
22、油路32を通り、後進流れ側油路18に合流され
ると同時に、パイロット切換弁19作用油路位置へ内の
他方の通路33、絞り部34付き油路を経て、油タンク
35に戻される。上記において、アンロードバルブ22
が作動しなかった場合(油路遮断状態の場合)には、前
進流れ側油路17内の圧油の一部は、パイロット切換弁
1つの作用油路位置へ内の絞り部2つ、通路33、絞り
部34付き油路を経て、油タンク35に戻される。また
、上記パイロット切換弁19が作用油路位置トに切換わ
っなときには、前進流れ側油路17内の一部の圧油は上
記作用油路位置ト内の絞り部40を通じ、一方は通路3
6、油路30を経て、アンロードバルブ22のパイロッ
トボート24に作用するとともに作用油路位置ト内の絞
り部40下流側にて分岐し絞り部37付き通路、絞り部
34付き油路を通じて、油タンク35に戻される。また
、上記パイロット切換弁19が作用油路位置チに切換わ
ったときには、前進流れ側油路17内の圧油は上記作用
油路位置チ内の開通油路38を通じて、アンロードバル
ブ22のパイロットボート24に作用する上記のように
して前進流れ側油路17内の圧油の一部が可変ポンプ1
5や油タンク35に戻されるので、走行用油圧モータ1
6に供給される圧油圧力は低減される。
Next, the functions of the hydraulic transmission circuit 10' according to the present invention will be described. When the packet cylinder 6 of the wheel loader is operated, the operating pressure in the operating circuit 25 acts on the pilot pressure receiving part 20 of one pilot switching valve through the oil rI@26. Therefore, when one pilot switching valve switches from the cutoff oil passage position E to the working oil passage position, a part of the pressure oil in the forward flow side oil passage 17 is transferred to the oil passage 27, 28 and the pilot switching valve 19. The oil flows into the working oil passage position, where it passes through two internal constrictions, one of which acts on the pilot boat 24 of the unload valve 22 via a passage 39 and an oil passage 30. When the unload valve 22 is activated, the forward flow side oil passage 17
A part of the pressure oil inside passes through the oil passages 27 and 31, the unload valve 22, and the oil passage 32, and is merged into the reverse flow side oil passage 18, and at the same time, part of the oil inside the oil passage is transferred to the operating oil passage position of the pilot switching valve 19. The oil is returned to the oil tank 35 through the other passage 33 and the oil passage with the constriction part 34. In the above, the unload valve 22
If the oil passage does not operate (oil passage is blocked), part of the pressure oil in the forward flow side oil passage 17 is transferred to the operating oil passage position of one pilot switching valve through the two constricted portions inside the passage. 33, and is returned to the oil tank 35 through an oil path with a constriction part 34. Further, when the pilot switching valve 19 is not switched to the working oil passage position G, a part of the pressure oil in the forward flow side oil passage 17 passes through the throttle part 40 in the working oil passage position G, and one part of the pressure oil passes through the passage 3.
6. Via the oil passage 30, it acts on the pilot boat 24 of the unload valve 22, and branches at the downstream side of the throttle part 40 in the working oil passage position T, and passes through the passage with the throttle part 37 and the oil passage with the throttle part 34, The oil is returned to the oil tank 35. Further, when the pilot switching valve 19 is switched to the working oil path position H, the pressure oil in the forward flow side oil passage 17 is transferred to the pilot of the unload valve 22 through the open oil passage 38 in the working oil path position H. A portion of the pressure oil in the forward flow side oil passage 17 acting on the boat 24 as described above is transferred to the variable pump 1.
5 and the oil tank 35, the traveling hydraulic motor 1
The hydraulic pressure supplied to 6 is reduced.

以上述べたように、ホイールローダが前進して土質など
の掘起し操作を行ったとき、パケット7に大きな負荷が
かかると、走行用油圧モータ16に供給される圧油圧力
が低下する。すなわち走行用油圧伝動装置回路10′の
吸収トルクを低減せしめて、パケット掘起し力優先の回
路状態にすることができる。それにより、走行用油圧伝
動装置回路10’をそなえたホイールローダでは、良い
掘削性能を発揮することができる。
As described above, when the wheel loader moves forward and excavates soil, etc., and a large load is applied to the packet 7, the hydraulic pressure supplied to the travel hydraulic motor 16 decreases. That is, it is possible to reduce the absorption torque of the travel hydraulic transmission circuit 10' and to create a circuit state in which the packet digging force is prioritized. As a result, the wheel loader equipped with the travel hydraulic transmission circuit 10' can exhibit good excavation performance.

発明の効果 作業機用駆動回路と走行用油圧伝動装置回路とをそなえ
た従来技術作業車両では、トルコン式車両の場合と異な
り、作業機たとえばパケットに大きな負荷が作用したと
きエンジン回転数が変化した(実際には可変ポンプの馬
力制御によりエンジン回転数は余り変化しない)として
も、その吸収トルクは殆ど変化しない。そのためにエン
ジン1〜ルクはけん引力優先の掘削性能となり、パケッ
トの掘起し操作が困難になっていた。
Effects of the Invention In conventional work vehicles equipped with a drive circuit for a work machine and a hydraulic transmission circuit for traveling, unlike the case of a torque converter type vehicle, the engine speed changes when a large load is applied to a work machine, for example, a packet. (Actually, the engine speed does not change much due to the horsepower control of the variable pump), but the absorbed torque hardly changes. For this reason, the excavation performance of engines 1 to LUQ prioritizes traction power, making it difficult to excavate the packet.

しかしこの発明にかかる油圧伝動装置回路では前進流れ
側油路にパイロット切換弁と、そのパイロット切換弁に
より制御されるアンロードバルブを設け、さらに作業機
用油圧アクチュエータに作用する作動圧からの信号によ
り上記パイロット切換弁を切換作動させるようにした。
However, in the hydraulic transmission circuit according to the present invention, a pilot switching valve and an unloading valve controlled by the pilot switching valve are provided in the forward flow side oil passage, and furthermore, a signal from the operating pressure acting on the hydraulic actuator for the work machine is used. The above-mentioned pilot switching valve is operated to switch.

それにより、ホイールローダが前進して土質などの掘起
し操作を行ったとき、作業機であるパケットに大きな負
荷がかかると、走行用油圧モータに供給される圧油圧力
は低下する。すなわち走行用油圧伝動装置回路の吸収ト
ルクを低減せしめて、パケット掘起し力優先の回路状態
にすることができる。
As a result, when the wheel loader moves forward to excavate soil, etc., and a large load is applied to the working machine, the packet, the hydraulic pressure supplied to the travel hydraulic motor decreases. That is, it is possible to reduce the absorption torque of the traveling hydraulic transmission device circuit and create a circuit state in which priority is given to the packet digging force.

したがって、この発明にかかる油圧伝動装置回路をそな
えた作業車両では、前進して作業機を操作しているとき
のそ作業機に大きな負荷がかかると、走行用油圧伝動装
置回路の発生トルクを低減せしめて、作業機優先の作業
性能を発揮する。
Therefore, in a working vehicle equipped with the hydraulic transmission circuit according to the present invention, when a large load is applied to the working machine while moving forward and operating the working machine, the generated torque of the traveling hydraulic transmission circuit is reduced. At the very least, the work performance is given priority to the work machine.

【図面の簡単な説明】[Brief explanation of drawings]

第1図はこの発明にかかる油圧伝動装置回路図第2図は
ホイールローダの側面図、第3図はパケット操作時のけ
ん引力−掘起し力線図、第71図はホイールローダの前
進掘起し時におけるエンジン回転数−吸収トルク曲線図
、第5図は従来技術油圧伝動装置回路図である。 6         パケットシリンダ7      
  パケット 9        作業機用駆動回路 10.10     油圧伝動装置回路11     
  エンジン 12       作業機用油圧ポンプ15     
  可変ポンプ 16       走行用油圧モータ 17       前進流れ側油路 18       後進流れ側油路 1つ       パイロツ1へ切換弁アンロードバル
ブ 以      上 特  許  出  願  人 油谷重工株式会社 代表者 早良 俊昭 第1図 ノh^− 粥 ノ−^− 弔 jすん引力 3図 一ヒ^− 弔 図 手 続 補 正  書 平成1年 ■ 7月17日
Fig. 1 is a hydraulic transmission circuit diagram according to the present invention. Fig. 2 is a side view of a wheel loader. Fig. 3 is a traction force-excavation force line diagram during packet operation. Fig. 71 is a forward excavation of the wheel loader. FIG. 5 is a diagram of the engine rotational speed-absorbed torque curve at the time of startup, and is a circuit diagram of a conventional hydraulic transmission device. 6 Packet cylinder 7
Packet 9 Work machine drive circuit 10.10 Hydraulic transmission circuit 11
Engine 12 Hydraulic pump 15 for work equipment
Variable pump 16 Hydraulic motor for traveling 17 Forward flow side oil passage 18 Reverse flow side 1 oil passage Switching valve to pilot 1 Unload valve Patent application Jinyuutani Heavy Industries Co., Ltd. Representative Toshiaki Sawara Figure 1 no h^ - Congee ^ - Condolences 3 Diagram 1 Hi ^ - Funeral diagram procedure amendment book 1999 ■ July 17th

Claims (1)

【特許請求の範囲】[Claims] (1)作業機用駆動回路と走行用油圧伝動装置回路とを
そなえた作業車両において、上記走行用油圧伝動装置回
路の前進流れ側油路にパイロット切換弁と、そのパイロ
ット切換弁により制御されるアンロードバルブを設け、
さらに作業機用油圧アクチュエータに作用する作動圧か
らの信号により上記パイロット切換弁を切換作動させる
ようにし、そのパイロット切換弁の切換作動により、走
行用油圧モータに供給される圧油圧力を上記アンロード
バルブを介して調整するようにして構成したことを特徴
とする作業車両の油圧伝動装置回路。
(1) In a work vehicle equipped with a work equipment drive circuit and a traveling hydraulic transmission circuit, a pilot switching valve is provided in the forward flow side oil passage of the traveling hydraulic transmission circuit, and the pilot switching valve is controlled by the pilot switching valve. Install an unload valve,
Further, the pilot switching valve is switched by a signal from the operating pressure acting on the hydraulic actuator for the work equipment, and the switching operation of the pilot switching valve unloads the hydraulic pressure supplied to the travel hydraulic motor. A hydraulic transmission circuit for a work vehicle, characterized in that the circuit is configured to be adjusted via a valve.
JP1061871A 1989-03-13 1989-03-13 Work vehicle hydraulic power transmission circuit Expired - Lifetime JP2775461B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP1061871A JP2775461B2 (en) 1989-03-13 1989-03-13 Work vehicle hydraulic power transmission circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP1061871A JP2775461B2 (en) 1989-03-13 1989-03-13 Work vehicle hydraulic power transmission circuit

Publications (2)

Publication Number Publication Date
JPH02240334A true JPH02240334A (en) 1990-09-25
JP2775461B2 JP2775461B2 (en) 1998-07-16

Family

ID=13183619

Family Applications (1)

Application Number Title Priority Date Filing Date
JP1061871A Expired - Lifetime JP2775461B2 (en) 1989-03-13 1989-03-13 Work vehicle hydraulic power transmission circuit

Country Status (1)

Country Link
JP (1) JP2775461B2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011184886A (en) * 2010-03-05 2011-09-22 Komatsu Ltd Working vehicle and method for controlling the same
CN114132314A (en) * 2021-12-20 2022-03-04 杭叉集团股份有限公司 Industrial vehicle turning deceleration control system and method thereof

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS52135310A (en) * 1976-05-07 1977-11-12 Asahi Denka Kogyo Kk Whipping o/w type fat emulsion
JPS62286848A (en) * 1986-06-04 1987-12-12 Hitachi Constr Mach Co Ltd Hydraulic drive type traveling device

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS52135310A (en) * 1976-05-07 1977-11-12 Asahi Denka Kogyo Kk Whipping o/w type fat emulsion
JPS62286848A (en) * 1986-06-04 1987-12-12 Hitachi Constr Mach Co Ltd Hydraulic drive type traveling device

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011184886A (en) * 2010-03-05 2011-09-22 Komatsu Ltd Working vehicle and method for controlling the same
CN114132314A (en) * 2021-12-20 2022-03-04 杭叉集团股份有限公司 Industrial vehicle turning deceleration control system and method thereof
CN114132314B (en) * 2021-12-20 2023-09-01 杭叉集团股份有限公司 Industrial vehicle turning deceleration control system and method thereof

Also Published As

Publication number Publication date
JP2775461B2 (en) 1998-07-16

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