JPH0837814A - Steering device for turning tractor - Google Patents
Steering device for turning tractorInfo
- Publication number
- JPH0837814A JPH0837814A JP18209894A JP18209894A JPH0837814A JP H0837814 A JPH0837814 A JP H0837814A JP 18209894 A JP18209894 A JP 18209894A JP 18209894 A JP18209894 A JP 18209894A JP H0837814 A JPH0837814 A JP H0837814A
- Authority
- JP
- Japan
- Prior art keywords
- steering
- brake
- reducing valve
- turning
- rear wheel
- 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
- Guiding Agricultural Machines (AREA)
- Arrangement And Driving Of Transmission Devices (AREA)
- Non-Deflectable Wheels, Steering Of Trailers, Or Other Steering (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】この発明は、トラクタの操向旋回
装置に関する。操向旋回時にハンドルの操向に連動し
て、前輪増速、操向ブレーキ、及び作業機の上昇等を自
動的に行わせるものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering turning device for a tractor. When the steering wheel is turned, the front wheels are automatically accelerated, the steering brake is operated, and the working machine is lifted in conjunction with the steering operation of the steering wheel.
【０００２】[0002]
【従来の技術、及び発明が解決しようとする課題】操向
旋回時にハンドルの操向に連動して、後輪操向ブレーキ
５を効かせる形態では、ブレーキ力の強、弱二段の切替
が行われるものがあるが、円滑な旋回を行い難い。2. Description of the Related Art In a mode in which the rear wheel steering brake 5 is activated by interlocking with the steering operation of the steering wheel during steering turning, the braking force can be switched between strong and weak. There are things that are done, but it is difficult to make a smooth turn.
【０００３】[0003]
【課題を解決するための手段】ステアリングハンドル１
の前輪２操向角によって、リフトアーム３の上昇と、前
輪増速装置４の増速位置と、後輪操向ブレーキ５の制動
とを行わせる自動旋回油圧回路６において、減圧弁７を
有して該前輪増速装置４の増速クラッチ８を作動する増
速切替弁９と、この減圧弁７から圧力補償される二次圧
側に比例減圧弁１０を介して後輪操向ブレーキ５を制動
するように設けてなるトラクタの操向旋回装置の構成と
する。Means for Solving the Problems Steering handle 1
A pressure reducing valve 7 is provided in an automatic swing hydraulic circuit 6 for raising the lift arm 3, increasing the position of the front wheel speed increasing device 4, and braking the rear wheel steering brake 5 according to the steering angle of the front wheels 2. Then, the speed increasing switching valve 9 for operating the speed increasing clutch 8 of the front wheel speed increasing device 4 and the rear wheel steering brake 5 via the proportional pressure reducing valve 10 on the secondary pressure side which is pressure-compensated from the pressure reducing valve 7. A steering turning device for a tractor provided so as to brake.
【０００４】[0004]
【作用、及び発明の効果】自動旋回油圧回路６において
は、ステアリングハンドル１で前輪２を操向して旋回す
るとき、この操向角によって上昇弁が出力されてリフト
アーム３が非作業高さに上昇され、増速切替弁９が出力
されて増速クラッチ８により前輪増速装置４が伝動され
て前輪２が後輪よりも高速となり、又操向ブレーキ弁の
出力によって後輪操向ブレーキ５が制動される。前輪２
が変速駆動されながらこの操向と後輪の操向ブレーキ５
制動とによって旋回される。比例減圧弁１０は、予め走
行条件等に応じて操向旋回の行い易い圧力に調節設定し
ておく。In the automatic turning hydraulic circuit 6, when the steering wheel 1 turns the front wheel 2 to turn, the lift valve is output according to this steering angle, and the lift arm 3 moves to a non-working height. The front wheel speed-increasing device 4 is transmitted by the speed-increasing clutch 8 and the front wheel 2 becomes faster than the rear wheel, and the rear-wheel steering brake is output by the output of the steering brake valve. 5 is braked. Front wheel 2
This steering and rear wheel steering brake 5
It is turned by braking. The proportional pressure reducing valve 10 is adjusted and set in advance to a pressure that facilitates steering turning according to the traveling conditions and the like.
【０００５】このような操向旋回制御において、後輪操
向ブレーキ５の油圧回路には、減圧弁７と比例減圧弁１
０とによる二段の減圧が仂くために、この比例減圧弁１
０の圧力設定を安定させることができ、無段階の操向ブ
レーキ圧調節によって、走行条件に応じた幅広いブレー
キ圧力を調節設定でき、安定した円滑な走行旋回を行う
ことができる。In such steering turning control, the pressure reducing valve 7 and the proportional pressure reducing valve 1 are provided in the hydraulic circuit of the rear wheel steering brake 5.
The proportional pressure reducing valve 1
The pressure setting of 0 can be stabilized, and the stepless steering brake pressure adjustment allows a wide range of brake pressures to be adjusted and set according to traveling conditions, and stable and smooth traveling turning can be performed.
【０００６】[0006]
【実施例】トラクタ車体１１は、ステアリングハンドル
１によって操向自在の左右一対の前輪２と、操縦席１２
後部の左右一対の後輪１３とを有して、エンジンによっ
て各々伝動して走行する。リフトアーム３は、この車体
１１の後部において油圧シリンダ１４のピストン１５の
伸縮作動によって上下回動される。EXAMPLE A tractor vehicle body 11 includes a pair of left and right front wheels 2 which can be steered by a steering wheel 1 and a cockpit 12.
It has a pair of left and right rear wheels 13 at the rear and is driven by the engine to travel. The lift arm 3 is rotated up and down by the expansion and contraction operation of the piston 15 of the hydraulic cylinder 14 at the rear portion of the vehicle body 11.
【０００７】前輪増速装置４は、車体１１のミッション
ケース内に設けられ、主変速装置や副変速装置等を経て
後輪１３連動の後輪デフ装置へ至る伝動装置の途中から
分岐して、前輪２連動の前輪デフ装置へ至る間の伝動装
置において、湿式多板形態の増速クラッチの切替によっ
て、前輪２へ伝動しない中立位置の後輪駆動（２ＷＤ）
から、前輪２を後輪１３とほぼ同速に駆動する前後輪駆
動（４ＷＤ）と、前輪２を後輪１３よりも変速の駆動と
する前輪増速駆動（４ＷＤＦ）とに切替えて伝動するこ
とができる。The front wheel speed-increasing device 4 is provided in the transmission case of the vehicle body 11 and is branched from the middle of the transmission device which reaches the rear wheel diff device interlocked with the rear wheel 13 through the main transmission device, the auxiliary transmission device and the like. In the transmission device to the front wheel differential device interlocking with the front wheels 2, the rear-wheel drive (2WD) in the neutral position where the transmission to the front wheels 2 is prevented by switching the wet multi-plate type speed increasing clutch.
From front to rear wheel drive (4WD) that drives the front wheels 2 at approximately the same speed as the rear wheels 13 and front wheel speed-increasing drive (4WDF) that drives the front wheels 2 to shift gears more than the rear wheels 13. You can
【０００８】後輪操向ブレーキ５は、前記後輪デフ装置
から左右の後輪１３へ伝動する各車軸１６に対して独立
的に制動しうる構成とし、左右一対のブレーキペタル１
７の操作で、ロッド１８を介してブレーキアーム１９を
連動して後輪操向ブレーキ５を制動することができる。
又、ブレーキシリンダ２０のピストン２１を介しても、
このブレーキアーム１９を押して制動することができ、
このブレーキシリンダ２０の油圧回路２３は、コントロ
ーラからの出力によって切替作動されるソレノイドバル
ブからなる操向ブレーキ弁２２と比例減圧弁１０とを有
する。The rear wheel steering brake 5 is constructed so that it can independently brake each axle 16 transmitted from the rear wheel differential device to the left and right rear wheels 13, and a pair of left and right brake petals 1 is provided.
By operating 7, the rear wheel steering brake 5 can be braked by interlocking the brake arm 19 via the rod 18.
Also, through the piston 21 of the brake cylinder 20,
You can press this brake arm 19 to brake,
The hydraulic circuit 23 of the brake cylinder 20 has a steering brake valve 22 composed of a solenoid valve which is switched and operated by an output from a controller, and a proportional pressure reducing valve 10.
【０００９】自動旋回油圧回路６は、油圧ポンプＰ１に
よってリリーフ弁２４を経て送られる油圧が、減圧弁７
によって一次圧側と二次圧側とに分流されて、この一次
圧側の回路にリフトアーム３を作動する油圧シリンダ１
４、及びこの上昇制御弁２５、下降制御弁２６、更には
作業機Ｗをローリング制御するローリングシリンダ２
７、及びこのローリング制御弁２８等を配置している。
２９は分流弁である。In the automatic swing hydraulic circuit 6, the hydraulic pressure sent from the hydraulic pump P1 via the relief valve 24 is reduced by the pressure reducing valve 7.
The hydraulic cylinder 1 is diverted by the primary pressure side and the secondary pressure side by the operation to operate the lift arm 3 in the circuit on the primary pressure side.
4 and the ascending control valve 25, the descending control valve 26, and the rolling cylinder 2 that controls the working machine W for rolling.
7, and the rolling control valve 28 and the like are arranged.
29 is a shunt valve.
【００１０】前記二次圧側の回路に、前記増速切替弁９
によって制御される増速クラッチ８のクラッチシリンダ
３０が設けられ、又、比例減圧弁１０、及び操向ブレー
キ弁２２によって制御される後輪操向ブレーキ５のブレ
ーキシリンダ２０が各々連通される。該比例減圧弁１０
の圧力はコントローラからの出力によって適切な圧力に
調節することができる。The speed increasing switching valve 9 is provided in the circuit on the secondary pressure side.
The clutch cylinder 30 of the speed-up clutch 8 controlled by the above is provided, and the proportional pressure reducing valve 10 and the brake cylinder 20 of the rear wheel steering brake 5 controlled by the steering brake valve 22 are communicated with each other. The proportional pressure reducing valve 10
The pressure can be adjusted to an appropriate pressure by the output from the controller.
【００１１】３１はパワステアリングで、油圧ポンプＰ
２の油圧回路に設けられる。Ｔはタンクポートである。
ステアリングハンドル１の軸には、この軸の回動を検出
するステアリングセンサ３２が設けられ、このステアリ
ングセンサ３２による操向角をコントローラ３３に入力
して、前記上昇制御弁２５や、増速切替弁９、及び操向
ブレーキ弁２２等を出力することができる。A power steering 31 is a hydraulic pump P.
2 hydraulic circuit. T is a tank port.
A steering sensor 32 for detecting the rotation of the steering wheel 1 is provided on the shaft of the steering wheel 1. The steering angle by the steering sensor 32 is input to a controller 33, and the raising control valve 25 and the speed increasing switching valve are provided. 9, the steering brake valve 22 and the like can be output.
【００１２】例えば、ステアリングハンドル１を左側へ
回動して左側旋回するときは、このステアリングハンド
ル１の切り角が一定以上になったことをステアリングセ
ンサ３２で検出し、コントローラ３３からの出力によっ
て上昇制御弁２５が作動されて、リフトシリンダ１４へ
油圧が送込まれ、ピストン１５を作動してリフトアーム
３が上昇され、作業機Ｗが地面から上昇され非作業位置
となる。For example, when turning the steering handle 1 to the left and turning to the left, the steering sensor 32 detects that the steering wheel 1 has a cut angle of a certain value or more, and the controller 33 raises the output. The control valve 25 is actuated, hydraulic pressure is sent to the lift cylinder 14, the piston 15 is actuated, the lift arm 3 is raised, and the work implement W is raised from the ground to the non-working position.
【００１３】これと同時に、減圧弁７を経る二次圧力の
もとに、増速切替弁９の作動によって増速クラッチシリ
ンダ３０の増速クラッチ８が作動され、これまで後輪駆
動（２ＷＤ）又は前後輪駆動（４ＷＤ）で駆動されてい
た車輪伝動は、増速クラッチ８の入りで前輪２の駆動が
後輪１３のほぼ二倍の変速度に回転される。更には、操
向ブレーキ弁２２の切替によって左側のブレーキシリン
ダ２０の油圧力が、比例減圧弁１０で調節設定された圧
力のもとに送込まれて、左側の後輪操向ブレーキ５Ｌが
制動される。この結果、操縦席は作業畝端部において、
ステアリングハンドル１の旋回操作を行うのみで、作業
機Ｗの上昇、前輪増速駆動、及び後輪１３の操向ブレー
キ５の制動等を自動的に行って、速かな旋回を行うこと
ができ、操作が簡単であり、又、操向ブレーキ５は、減
圧弁７と比例減圧弁１０とによる２段階の減圧によって
安定した油圧による制動を受ける。At the same time, under the secondary pressure passing through the pressure reducing valve 7, the speed increasing clutch 8 of the speed increasing clutch cylinder 30 is operated by the operation of the speed increasing switching valve 9, and the rear wheel drive (2WD) has been performed so far. Alternatively, in the wheel transmission that was driven by the front-rear wheel drive (4WD), the drive of the front wheel 2 is rotated to a speed twice that of the rear wheel 13 when the speed increasing clutch 8 is engaged. Further, by switching the steering brake valve 22, the hydraulic pressure in the left brake cylinder 20 is fed under the pressure adjusted and set by the proportional pressure reducing valve 10, and the left rear wheel steering brake 5L is braked. To be done. As a result, the cockpit is at the work ridge end,
Only by performing a turning operation of the steering handle 1, it is possible to perform a quick turn by automatically raising the work implement W, increasing the speed of the front wheels, and braking the steering brake 5 of the rear wheels 13. The operation is simple, and the steering brake 5 is braked by a stable hydraulic pressure by the two-stage pressure reduction by the pressure reducing valve 7 and the proportional pressure reducing valve 10.
【００１４】図３において、上例と異なる点は、前記比
例減圧弁１０に代えて、固定絞り３４を有した弱制動と
このような絞りを有しない強制動とに切替えできるブレ
ーキ力切替弁３５を設けたもので、手動操作のスイッチ
によりソレノイド３６で切替えできる。図４において、
上例と異なる点は、前記左右のブレーキシリンダ２０に
代えて、ピストン径及び受圧面積の異なるエリアＡ，Ｂ
を形成したブレーキシリンダ３７を設け、この各エリア
Ａ，Ｂに対する油圧切替を行う切替弁３８を設ける。こ
の切替弁３８は手動で操作するもよいが、他の操向旋回
操作と連動させる構成とするもよい。ブレーキシリンダ
３７は大径部と小径部との二段に形成され、これに嵌合
するピストン３９も小径部３９Ａと大径部３９Ｂとに形
成して、各エリアＡ，Ｂに対する油圧供給によって、ピ
ストン３９の押圧力が異なる構成としている。なお大径
部３９Ｂは小径部３９Ａと一体のスピンドル部４０とこ
の外周に嵌合するリング部４１とからなり、エリアＢに
供給される油圧力は、これらスピンドル部４０とリング
部４１との端面の面積に仂く油圧の総和として、スピン
ドル部４０を押圧Ｃして操向ブレーキ５Ｌ，５Ｒを制動
する。この場合、ピストン３９の小径部３９Ａの面積
は、リング４１における大径部３９Ｂの面積よりも狭く
形成している。In FIG. 3, the point different from the above example is that the proportional pressure reducing valve 10 is replaced by a braking force switching valve 35 capable of switching between weak braking having a fixed throttle 34 and forced operation having no such throttle. The solenoid 36 can be switched by a manually operated switch. In FIG.
The difference from the above example is that instead of the left and right brake cylinders 20, areas A and B having different piston diameters and pressure receiving areas are used.
A brake cylinder 37 is formed, and a switching valve 38 that switches the hydraulic pressure to each of the areas A and B is provided. The switching valve 38 may be manually operated, but may be configured to be interlocked with another steering turning operation. The brake cylinder 37 is formed in two stages of a large diameter portion and a small diameter portion, and a piston 39 fitted therein is also formed in the small diameter portion 39A and the large diameter portion 39B, and the hydraulic pressure is supplied to each of the areas A and B. The pressing force of the piston 39 is different. The large-diameter portion 39B is composed of a spindle portion 40 integrated with the small-diameter portion 39A and a ring portion 41 fitted to the outer periphery of the small-diameter portion 39A. The hydraulic pressure supplied to the area B is the end surface of the spindle portion 40 and the ring portion 41. As the sum of the hydraulic pressures over the area, the spindle unit 40 is pressed C to brake the steering brakes 5L and 5R. In this case, the area of the small diameter portion 39A of the piston 39 is formed smaller than the area of the large diameter portion 39B of the ring 41.
【００１５】このためエリアＡの油圧力に切替えられた
ときは、後輪操向ブレーキ５の制動力は弱く、又、エリ
アＢの油圧力に切替えられたときは、後輪操向ブレーキ
５の制動力は強く仂くことになる。図示しないが、リン
グ４１の左側端面であるエリアＢ内にリング４１を右方
に戻すスプリングを内装しておくと、油路中立時にリン
グ４１が右方に戻るから、強制動と弱制動に切り替えた
時のピストン３９のストロ−クに差を生じない。Therefore, when the hydraulic pressure is switched to the area A, the braking force of the rear wheel steering brake 5 is weak, and when the hydraulic pressure is switched to the area B, the rear wheel steering brake 5 is operated. The braking force will be strong. Although not shown, if a spring that returns the ring 41 to the right is installed in the area B, which is the left end surface of the ring 41, the ring 41 returns to the right when the oil passage is neutral, so switching between forced operation and weak braking is performed. There is no difference in the stroke of the piston 39 when the piston 39 is opened.
【００１６】図５〜図７において、上例と異なる点は、
前記リフトアーム３による作業機Ｗの上昇を後輪操向ブ
レーキ５Ｌ，５Ｒに対して優先的に為めに、前記作業機
Ｗを上昇させる上昇制御弁２５から油圧シリンダ１４に
至る間の上昇回路４２から、操向ブレーキ５のブレーキ
制御回路４３を分岐させて、このブレーキ制御回路４３
にシーケンスバルブ４４を設ける。ステアリングハンド
ル１の切り角によって、前記のように上昇制御弁２５が
作動されると、油圧シリンダ１４に油圧が立ち、作業機
Ｗ上昇圧力に達するまでは、ブレーキ制御回路４３では
シーケンスバルブ４４によって油圧が通らない。5 to 7, the difference from the above example is that
In order to preferentially raise the working machine W by the lift arm 3 with respect to the rear wheel steering brakes 5L, 5R, a raising circuit for raising the working machine W from the raising control valve 25 to the hydraulic cylinder 14. From 42, the brake control circuit 43 of the steering brake 5 is branched and the brake control circuit 43 is branched.
A sequence valve 44 is provided in the. When the raising control valve 25 is actuated by the turning angle of the steering wheel 1 as described above, the hydraulic pressure rises in the hydraulic cylinder 14 until the working machine W rising pressure is reached. Does not pass.
【００１７】シーケンスバルブ４４は、調節ボルト４５
で圧力調節自在のばね４６で押圧されるスプール４７
を、バルブケース４８に収容してなり、作業機Ｗを上昇
する油圧シリンダ１４への供給油圧力までは、後輪操向
ブレーキ５のブレーキシリンダ２０への油圧力を送らな
いで、これ以上の油圧力になるとピストン１５により作
業機Ｗを上昇し、バネ４６に抗してスプール４７が下か
ら押し上げられて開き、ブレーキ制御回路４３をとうし
て、操向ブレ−キ弁２２による切替えられた側の後輪操
向ブレ−キ５Ｌ、又は５Ｒが制動される。The sequence valve 44 has an adjusting bolt 45.
Spool 47 pressed by spring 46 whose pressure can be adjusted by
Is housed in the valve case 48, and the oil pressure to the brake cylinder 20 of the rear wheel steering brake 5 is not sent up to the oil pressure supplied to the hydraulic cylinder 14 for raising the working machine W. When the hydraulic pressure is reached, the working machine W is raised by the piston 15, the spool 47 is pushed up from the bottom against the spring 46 and opened, and the brake control circuit 43 is passed through to switch the steering brake valve 22. The rear wheel steering brake 5L or 5R on the side is braked.
【００１８】図８において、上例と異なる点は、後輪操
向ブレ−キ５を、ブレ−キカバ−４９に形成のブレ−キ
シリンダ２０にピストン２１を設け、油圧回路２３から
の油圧力でピストン２１を押圧して、プレッシャプレ−
ト５０を介して後輪操向ブレ−キ５Ｌ、又は５Ｒを押圧
制動する構成とし、又、このプレッシャプレ−ト５０
を、ボ−ル５１で受けるカム５２で案内させて、操作機
構で連動して回動されるクランクア−ム５３で係合回動
させて、該後輪操向ブレ−キ５Ｌ，５Ｒに押し圧されて
制動する構成としている。５４はこのブレ−キカバ−４
９をミッションケ−ス５５の側面に着脱するボルトであ
る。In FIG. 8, the difference from the above example is that the rear wheel steering brake 5 and the brake cylinder 20 formed on the brake cover 49 are provided with the piston 21 and the hydraulic pressure from the hydraulic circuit 23 is used. Press the piston 21 and press
The rear wheel steering brake 5L or 5R is configured to be pressed and braked via the valve 50, and the pressure plate 50
Is guided by a cam 52 received by a ball 51 and engaged and rotated by a crank arm 53 which is rotated in conjunction with an operating mechanism, and pushed to the rear wheel steering brakes 5L and 5R. It is configured to be pressed and braked. 54 is this blurring cover-4
A bolt for attaching and detaching 9 to the side surface of the mission case 55.
【００１９】５６は後輪デフ装置、５７は後車輪、５８
は車輪軸、５９はアクスルハウジング、６０は後車軸５
７と車輪軸５８との間を噛合伝動するギヤ、６１はデフ
ロック機構である。前記後輪操向ブレ−キ５は該後車軸
５７に設けられる。図９において、上例と異なる点は、
前記プレシャプレ−ト５０とピストン２１とを一体成形
の構成としたものである。Reference numeral 56 is a rear wheel differential device, 57 is a rear wheel, and 58.
Is a wheel axle, 59 is an axle housing, and 60 is a rear axle 5.
Reference numeral 61 denotes a diff-lock mechanism that meshes and transmits between 7 and the wheel shaft 58. The rear wheel steering brake 5 is provided on the rear axle 57. In FIG. 9, the difference from the above example is that
The pressure plate 50 and the piston 21 are integrally molded.
【図１】自動旋回油圧回路図。FIG. 1 is an automatic swing hydraulic circuit diagram.
【図２】そのブロック回路図。FIG. 2 is a block circuit diagram thereof.
【図３】一部別実施例を示す油圧回路図。FIG. 3 is a hydraulic circuit diagram showing a partially different embodiment.
【図４】一部別実施例を示す油圧回路図。FIG. 4 is a hydraulic circuit diagram showing another embodiment.
【図５】一部別実施例を示す油圧回路図。FIG. 5 is a hydraulic circuit diagram showing a partially different embodiment.
【図６】その一部の拡大図。FIG. 6 is an enlarged view of a part thereof.
【図７】その作動を示す拡大図。FIG. 7 is an enlarged view showing the operation.
【図８】ミッションケ−ス部の一部正面図。FIG. 8 is a partial front view of the mission case portion.
【図９】その一部別実施例を示す一部正面図。FIG. 9 is a partial front view showing an example of another part thereof.
１ ステアリングハンドル ２ 前輪 ３ リフトア−ム ４ 前輪増速装置 ５ 後輪操向ブレ−キ５ ６ 自動旋回油圧回路 ７ 減圧弁 ８ 増速クラッチ ９ 増速切替弁 １０ 比例減圧弁 1 Steering handle 2 Front wheel 3 Lift arm 4 Front wheel speed increasing device 5 Rear wheel steering brake 5 6 Automatic turning hydraulic circuit 7 Pressure reducing valve 8 Speed increasing clutch 9 Speed increasing switching valve 10 Proportional pressure reducing valve
Claims (1)
によって、リフトアーム３の上昇と、前輪増速装置４の
増速位置と、後輪操向ブレーキ５の制動とを行わせる自
動旋回油圧回路６において、減圧弁７を有して該前輪増
速装置４の増速クラッチ８を作動する増速切替弁９と、
この減圧弁７から圧力補償される二次圧側に比例減圧弁
１０を介して後輪操向ブレーキ５を制動するように設け
てなるトラクタの操向旋回装置。1. An automatic turning hydraulic circuit for raising a lift arm 3, a speed increasing position of a front wheel speed increasing device 4 and braking of a rear wheel steering brake 5 according to a steering angle of a front wheel 2 of a steering wheel 1. 6, a speed increasing switching valve 9 having a pressure reducing valve 7 for operating a speed increasing clutch 8 of the front wheel speed increasing device 4;
A steering turning device for a tractor provided so as to brake the rear wheel steering brake 5 via a proportional pressure reducing valve 10 on the secondary pressure side that is pressure-compensated from the pressure reducing valve 7.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18209894A JP3632991B2 (en) | 1994-08-03 | 1994-08-03 | Steering and turning device for tractor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18209894A JP3632991B2 (en) | 1994-08-03 | 1994-08-03 | Steering and turning device for tractor |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2003109042A Division JP3743434B2 (en) | 2003-04-14 | 2003-04-14 | Tractor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0837814A true JPH0837814A (en) | 1996-02-13 |
| JP3632991B2 JP3632991B2 (en) | 2005-03-30 |
Family
ID=16112317
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP18209894A Expired - Fee Related JP3632991B2 (en) | 1994-08-03 | 1994-08-03 | Steering and turning device for tractor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3632991B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106982591A (en) * | 2017-04-27 | 2017-07-28 | 浙江亿森机械有限公司 | A kind of baby combine transfer |
-
1994
- 1994-08-03 JP JP18209894A patent/JP3632991B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106982591A (en) * | 2017-04-27 | 2017-07-28 | 浙江亿森机械有限公司 | A kind of baby combine transfer |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3632991B2 (en) | 2005-03-30 |
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