JPS62149557A - Steering device for vehicle - Google Patents

Abstract

PURPOSE:To enable driving of a vehicle with the same sensation as that of a general vehicle during running approximately similar to linear running and to enable rapid turn of a vehicle, by a method wherein front wheels are put in motion in linkage with control of rotation in the whole range of a steering handle, and in a range exceeding the specified range of each range, a car body is designed to be bent. CONSTITUTION:A front car body 10 having front wheels 14 and a rear car body 17 having rear wheels 19 are bendably coupled with each other around a vertical shaft 24, and the front wheels 14 are supported around their respective kind pins 12 so as to allow free steering. An electromagnetic valve 32 is actuated in linkage with control of rotation within the whole range of a steering handle 20, a front wheel steering cylinder 16 is actuated, and the front wheels 14 are steered around their respective king pins 12. When the steering handle 20 is controlled in a range exceeding a specified range, the front wheels 14 is steered, an electromagnetic valve 33 is actuated, and a car body bending cylinder 25 is expanded and contracted to bend the car bodies 10 and 17 around the vertical shaft 24. This constitution enabled driving of a vehicle with the same sensation as that of a general vehicle during running in a range approximately similar to linear running, and also permits facilitation of rapid turn of a vehicle in a paddy field.

Description

【発明の詳細な説明】 （産業上の利用分野） 本発明は、車輌の操向装置に関するものである。[Detailed description of the invention] (Industrial application field) The present invention relates to a steering device for a vehicle.

（従来の技術） トラクタ等の車輌の操向装置としては、従来、第７図又
は第８図に示すようなものがある。(Prior Art) Conventionally, there is a steering device for a vehicle such as a tractor as shown in FIG. 7 or FIG. 8.

第７図は、車体１に備えた前輪２及び後輪３の内、前輪
２をキングピン廻りに回動自在とし、ハンドル操作によ
って前輪２を操向動作させ、旋回中心Ｏ廻り旋回するよ
うにしたものである。FIG. 7 shows a vehicle body 1 having a front wheel 2 and a rear wheel 3, of which the front wheel 2 is freely rotatable around a kingpin, and the front wheel 2 is steered by operating the steering wheel to turn around a turning center O. It is something.

第８図は、前部車体４及び後部車体５を縦軸６廻りに屈
折自在に連結し、ハンドル操作によって車体４．５が縦
軸６廻りに屈折して、旋回中心Ｏの廻りに旋回するよう
・にしたものである。FIG. 8 shows a front vehicle body 4 and a rear vehicle body 5 connected in a bendable manner around a vertical axis 6, and by operating the handle, the vehicle body 4.5 bends around the vertical axis 6 and turns around a turning center O. This is what I did.

′（発明が解決しようとする問題点） しかしながら、第７図及び第８図の何れの場合にも、前
輪２の切れ角、車体４，５の屈折角に制限があるため、
旋回半径を小さくすることができず、従って、急旋回の
際にタイヤのサイドスリップを防止し得ないため、タイ
ヤの損耗が著しくなる欠点があった。(Problems to be Solved by the Invention) However, in both the cases of FIG. 7 and FIG.
Since it is not possible to reduce the turning radius and, therefore, it is not possible to prevent the tires from slipping during sharp turns, there is a drawback that the tires are subject to significant wear and tear.

（問題点を解決するための手段） 本発明は、このような問題点を解決することを目的とし
たものであって、そのための手段として、前輪を有する
前部車体と、後輪を有する後部車体とを縦軸廻りに屈折
自在に連結すると共に、前輪をキングピン廻りに操向自
在に支持し、操向ハンドルの全範囲での回動操作に連動
して前輪をキングピン廻りに操向動作させる前輪操向シ
リンダと、前記全範囲の内の一定範囲を越えた範囲での
操向ハンドルの回動操作に連動して前後部車体を縦軸廻
りに屈折させる車体屈折シリンダとを設けたものである
。(Means for Solving the Problems) The present invention aims to solve these problems, and as a means for that purpose, a front body having front wheels and a rear body having rear wheels are provided. It is connected to the vehicle body so as to be bendable around the vertical axis, and supports the front wheels so that they can be steered around the king pin, and the front wheels are steered around the king pin in conjunction with the rotation operation of the steering wheel over the entire range. This vehicle is equipped with a front wheel steering cylinder and a vehicle body bending cylinder that bends the front and rear vehicle bodies around the longitudinal axis in conjunction with the turning operation of the steering handle in a range beyond a certain range within the above-mentioned total range. be.

（作　用） 操向ハンドル２０を操作すると、その全範囲で操向ハン
ドル２０に連動して電磁弁３２が働き、前輪操向シリン
ダ１６が作動し、前輪１４がキングピン１２廻りに操向
動作する。(Operation) When the steering handle 20 is operated, the solenoid valve 32 operates in conjunction with the steering handle 20 over its entire range, the front wheel steering cylinder 16 operates, and the front wheels 14 are steered around the king pin 12. .

操向ハンドル２０を一定範囲を越えた範囲で操作すると
、前輪１４が操向動作すると共に、電磁弁３３が働き、
車体屈折シリンダ２５が伸縮して車体１０゜１７が縦軸
２４廻りに屈折する。When the steering handle 20 is operated beyond a certain range, the front wheels 14 are steered and the solenoid valve 33 is activated.
The vehicle body bending cylinder 25 expands and contracts, and the vehicle body 10° 17 bends around the vertical axis 24.

（実施例） 以下、図示の実施例については本発明を詳述すると、第
１図は胴折れ型トラクタを示し、１０は前部車体で、こ
れにはエンジン等が設けられている。(Embodiment) The present invention will be described in detail below with reference to the illustrated embodiment. FIG. 1 shows a folding-body type tractor, and 10 is a front body, which is provided with an engine and the like.

１）は前車軸で、センター軸を介して前部車体１０に支
持されている。前車軸１）の左右両端にはキングピン１
２、ハブ軸１３を介して前輪１４が取付けられており、
この前輪１４はキングピン１２廻りに操向自在である。1) is a front axle, which is supported by the front vehicle body 10 via a center shaft. There are king pins 1 on both left and right ends of the front axle 1).
2. The front wheel 14 is attached via the hub axle 13,
This front wheel 14 can be freely steered around the king pin 12.

キングピン１２の上端は前方に突出するようにナックル
アーム１５が固着されている。左右のナックルアーム１
５間には、各前輪１４をキングピン１２廻りに操向動作
させるための前輪操向シリンダ１６が設けられており、
またこの前輪操向シリンダ１６の本体側は前車軸１）側
に支持されている。A knuckle arm 15 is fixed to the upper end of the king pin 12 so as to project forward. Left and right knuckle arms 1
A front wheel steering cylinder 16 for steering each front wheel 14 around the king pin 12 is provided between the front wheels 5 and 5.
Further, the main body side of this front wheel steering cylinder 16 is supported on the front axle 1) side.

１７は後部車体で、この後部車体１７の後部両側には後
車軸ケース１８等を介して後輪１９が支持されている。Reference numeral 17 denotes a rear vehicle body, and rear wheels 19 are supported on both rear sides of the rear vehicle body 17 via a rear axle case 18 and the like.

後輪１９はエンジンからの動力によって駆動される。後
部車体１７上には操向ハンドル２０と運転席２１とが設
けられている。The rear wheels 19 are driven by power from the engine. A steering handle 20 and a driver's seat 21 are provided on the rear vehicle body 17.

前部車体１０及び後部車体１７は、前後に配置されてお
り、その各車体１０．１７の対向端面に装着された上下
一対の前後ブラケット２２．２３と、これに挿通された
縦軸２４とにより、縦軸２４廻りに屈折自在に枢支連結
されている。また前部車体１０と後部車体１７との間に
は、その−側方に車体屈折シリンダ２５が設けられ、こ
の車体屈折シリンダ２５の伸縮により縦軸２４廻りに前
後部車体１０．１７が屈折するようになっている。The front vehicle body 10 and the rear vehicle body 17 are arranged in the front and rear, and are supported by a pair of upper and lower front and rear brackets 22.23 attached to opposite end surfaces of each vehicle body 10.17, and a vertical shaft 24 inserted therethrough. , are refractably pivotally connected around the longitudinal axis 24. Further, between the front vehicle body 10 and the rear vehicle body 17, a vehicle body bending cylinder 25 is provided on the negative side thereof, and the front and rear vehicle bodies 10.17 are bent around the vertical axis 24 by expansion and contraction of the vehicle body bending cylinder 25. It looks like this.

第２図はシリンダ１６．２５を含む油圧回路を示す。FIG. 2 shows the hydraulic circuit including cylinder 16.25.

前輪操向シリンダ１６にはその伸縮に連動して前輪１４
の切れ角を検出するように切れ角検出器２６が付設され
、また車体屈折シリンダ２５には同様にして車体１０．
１７の屈折角を検出する屈折角検出器２７が付設されて
いる。２８は油圧ポンプ、２９は分配弁、２９．３０．
３１はリリーフ弁である。３２．３３はシリンダ１６．
１７を制御する左右操向用の電磁弁で、右ソレノイド３
４　、３５　と左ソレノイド３６．３７　とを有する。The front wheel steering cylinder 16 is connected to the front wheel 14 in conjunction with its expansion and contraction.
A turning angle detector 26 is attached to detect the turning angle of the car body 10 . Similarly, the car body bending cylinder 25 is provided with a turning angle detector 26 to detect the turning angle of the car body 10 .
A refraction angle detector 27 for detecting 17 refraction angles is attached. 28 is a hydraulic pump, 29 is a distribution valve, 29.30.
31 is a relief valve. 32.33 is cylinder 16.
Right solenoid 3 is a solenoid valve for left/right steering that controls 17.
4, 35 and left solenoid 36, 37.

第３図は電磁弁３２．３３の駆動回路を示し、３８は指
令器で、操向ハンドル２０に連動するポテンショメータ
等から成り、操向シリンダ２０の回動操作により、指令
信号を出力する。３９は第１比較器で、指令器３８から
の指令信号と切れ角検出器２６からの検出信号とを比較
して、その正又は負の信号によって電磁弁３２のソレノ
イド３４又は３６に通電するようになっている。４０は
第２比較器で、指令器３８からの指令信号と屈折角検出
器２７からの検出信号とを比較して、その正又は負の信
号によってゲート回路４１．４２を介して電磁弁３３の
ソレノイド３５又は３７に通電するようになっている。FIG. 3 shows a drive circuit for the electromagnetic valves 32 and 33. Reference numeral 38 is a command device, which is composed of a potentiometer and the like that are linked to the steering handle 20, and outputs a command signal when the steering cylinder 20 is rotated. 39 is a first comparator that compares the command signal from the command unit 38 and the detection signal from the turning angle detector 26, and energizes the solenoid 34 or 36 of the solenoid valve 32 depending on the positive or negative signal. It has become. 40 is a second comparator that compares the command signal from the command unit 38 and the detection signal from the refraction angle detector 27, and controls the solenoid valve 33 via gate circuits 41 and 42 depending on the positive or negative signal. The solenoid 35 or 37 is energized.

４３は第３比較器で、切れ角検出器２６からの検出信号
と基準信号４４とを比較して、両者が一致した時に操向
ハンドル２０の全回動範囲（Ｏ〜７２０°）の内、半分
の位置（３６０’　）　　を判断するようになっており
、その出力によってゲート回路４１．４２を開くように
構成されている。従って、電磁弁３３は操向ハンドル２
０を３６０°〜７２０°の範囲で操作した時にのみ連動
して作動するようになっている。43 is a third comparator that compares the detection signal from the steering angle detector 26 with the reference signal 44, and when the two match, the signal within the entire rotation range (0 to 720 degrees) of the steering handle 20 is detected. The half position (360') is determined, and the gate circuits 41 and 42 are opened by the output thereof. Therefore, the solenoid valve 33 is connected to the steering handle 2.
It is designed to operate in conjunction only when 0 is operated within the range of 360° to 720°.

上記構成において、操向ハンドル２０を例えばＯ〜３６
０°の範囲内が左方向に操作すると、指令器３８がその
回動角に応じた左操向指令％ｖ−αを発し、前輪１４側
の切れ角検出器２６の検出信号と左操向指令とを比較器
３９で比較する。操向ハンドル２０の操作前が直進状態
であれば、切れ角検出器２６の信号が％Ｖであるため、
比較器３９より−αの負信号が出力し、電磁弁３２が左
ソレノイド３６が通電され、電磁弁３２が左操向に切換
ねる。従って、前輪操向シリンダ１６のピストンロッド
が左方向に移動し、第４図の特性Ａに沿って第５図の如
く前輪１４がキングピン１２廻りに左側に操向動作をす
る。この場合の前輪１４の最大切れ角は約３０’程度で
あるが、操向ハンドル２０の全範囲にわたる回動操作に
連動して前輪１４が操向動作する。従って、操向ハンド
ル２０の回動操作量に対する前輪１４の切れ角は小さく
、圃場内での直進走行性能が良好である。In the above configuration, the steering handle 20 is, for example, O-36.
When the steering wheel is operated to the left within the range of 0°, the command unit 38 issues a left steering command %v-α according to the rotation angle, and the detection signal of the turning angle detector 26 on the front wheel 14 side and the left steering command are output. A comparator 39 compares the command with the command. If the steering wheel 20 is in the straight-ahead state before the steering wheel 20 is operated, the signal from the turning angle detector 26 is %V, so
A negative signal of -α is output from the comparator 39, the left solenoid 36 of the solenoid valve 32 is energized, and the solenoid valve 32 is switched to left steering. Therefore, the piston rod of the front wheel steering cylinder 16 moves to the left, and the front wheel 14 steers to the left around the king pin 12 as shown in FIG. 5 in accordance with characteristic A in FIG. Although the maximum turning angle of the front wheels 14 in this case is about 30', the front wheels 14 perform a steering operation in conjunction with the rotation operation of the steering handle 20 over the entire range. Therefore, the turning angle of the front wheels 14 relative to the amount of rotation of the steering handle 20 is small, and the straight running performance in the field is good.

一方、操向ハンドル２０が３６０°以内にある時には、
第３比較器４３の出力によってゲート回路４１゜４２が
開いておらず、従って、車体屈折シリンダ２５が動作し
ないので、車体１０．１７は一直線状のままであり、路
上走行に際しても通常の車輌と同様に運転できる。On the other hand, when the steering wheel 20 is within 360°,
Since the gate circuits 41 and 42 are not opened by the output of the third comparator 43, and therefore the body bending cylinder 25 does not operate, the body 10.17 remains in a straight line, and when driving on the road, it behaves like a normal vehicle. You can drive as well.

操向ハンドル２０を３６０°を越えて操作すると、前述
の如く前輪■４が操向動作すると共に、車体屈折シリン
ダ２５の動作によって車体１０．１７が屈折する。即ち
、操向ハンドル２０が３６０°まで回動すると、第３比
較器４３の出力によってゲート回路４１゜４２が開く。When the steering handle 20 is operated over 360 degrees, the front wheels 4 are steered as described above, and the vehicle body 10.17 is deflected by the operation of the vehicle deflection cylinder 25. That is, when the steering handle 20 rotates through 360 degrees, the output of the third comparator 43 opens the gate circuits 41 and 42.

一方、このゲート回路４１．４２が開いた後、操向ハン
ドル２０が更に回動すると、指令器３８の左操向指令と
屈折角検出器２７の検出信号を第２比較器４０で比較し
、その差の負信号によって電磁弁３３の左ソレノイド３
７が励磁して電磁弁３３が左操向に切換ねり、車体屈折
シリンダ２５が収縮動作をする。従って、車体１０．１
７は第４図の特性Ｂに沿って第６図の如く屈折するので
あり、前輪１４側の操向動作とも併せて全体の操舵角は
第４図の特性Ｃの通りとなる。このため操向ハンドル２
０が３６０“を越えた範囲においては、操向ハンドル２
０の単位操作角に対する全体の操舵角の変化が非常に大
となり、圃場内での急旋回時のハンドル操作が容易であ
る。On the other hand, when the steering handle 20 further rotates after the gate circuits 41 and 42 open, the left steering command from the command unit 38 and the detection signal from the refraction angle detector 27 are compared by the second comparator 40, The left solenoid 3 of the solenoid valve 33 is activated by the negative signal of the difference.
7 is excited, the solenoid valve 33 switches to left steering, and the vehicle body bending cylinder 25 performs a contraction operation. Therefore, the car body 10.1
7 is bent as shown in FIG. 6 along characteristic B of FIG. 4, and in conjunction with the steering operation of the front wheels 14, the entire steering angle becomes as shown in characteristic C of FIG. 4. For this reason, the steering handle 2
In the range where 0 exceeds 360", the steering handle 2
The change in the overall steering angle with respect to a unit operation angle of 0 is very large, making it easy to operate the steering wheel when making sharp turns in the field.

操向ハンドル２０を逆に操作すれば、前述とは逆に動作
する。なお、シリンダ１６．２５が最大限動作した後は
、リリーフ弁３０．３１が働き、電磁弁３２゜３３が損
傷することはない。If the steering handle 20 is operated in the opposite direction, the operation will be reversed to that described above. It should be noted that after the cylinder 16.25 has been operated to the maximum, the relief valve 30.31 will work and the solenoid valves 32 and 33 will not be damaged.

（発明の効果） 本発明によれば、操向ハンドルの全範囲での回動操作に
連動して前輪が操向動作すると共に、全範囲の内の一定
範囲を越えた範囲では車体が屈折するようにしているの
で、道路走行や作業中の直進走行が容易になると共に、
直線に近い範囲での操向時には一般車輌と同じ感覚で運
転でき、また圃場内での急旋回も容易にできる。特に、
一定範囲を越えると、操向ハンドルに連動して前輪と車
体とが共に動作するので、ハンドル操作に対する操舵角
の変化が大となり、急旋回時のハンドル操作が容易にな
る。しかも、前輪のみの操向でないので、前輪のタイヤ
径も大きくすることが可能であり、四輪駆動の時に便利
である。(Effects of the Invention) According to the present invention, the front wheels are steered in conjunction with the turning operation of the steering wheel over the entire range, and the vehicle body is deflected beyond a certain range within the entire range. This makes it easier to drive straight on the road or while working, and
When steering in a nearly straight line, you can drive with the same feeling as a regular vehicle, and you can easily make sharp turns in the field. especially,
When a certain range is exceeded, the front wheels and the vehicle body move together in conjunction with the steering wheel, so the change in steering angle relative to the steering wheel operation becomes large, making it easier to operate the steering wheel during sharp turns. Moreover, since the steering is not limited to the front wheels, it is possible to increase the diameter of the front tires, which is convenient when using four-wheel drive.

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

第１図乃至第６図は本発明の一実施例を示すものであっ
て、第１図は全体の平面図、第２図は油圧回路図、第３
図は電気回路図、第４図はハンドル回動角と操舵角との
関係の説明図、第５図及び第６図は作用説明図、第７図
及び第８図は従来例を示す説明図である。 １〇−前部車体、１２−キングピン、１４−・−前輪、
１６−・・前輪操向シリンダ、１７・・・後部車体、２
〇−操向ハンドル、２５−・・−車体屈折シリンダ、２
〇−前輪切れ角検出器、２７−屈折角検出器、３２．３
３−電磁弁、３８−・指令器、３９　、４０　、４３−
比較器。1 to 6 show one embodiment of the present invention, in which FIG. 1 is an overall plan view, FIG. 2 is a hydraulic circuit diagram, and FIG. 3 is a hydraulic circuit diagram.
The figure is an electric circuit diagram, Figure 4 is an explanatory diagram of the relationship between the steering wheel rotation angle and the steering angle, Figures 5 and 6 are explanatory diagrams of the operation, and Figures 7 and 8 are explanatory diagrams showing the conventional example. It is. 10-Front body, 12-King pin, 14-.-Front wheel,
16-...Front wheel steering cylinder, 17...Rear vehicle body, 2
〇-Steering handle, 25-...-Vehicle body bending cylinder, 2
〇-Front wheel steering angle detector, 27-Refraction angle detector, 32.3
3-Solenoid valve, 38-・Command device, 39, 40, 43-
Comparator.

Claims (1)

【特許請求の範囲】[Claims] （１）前輪を有する前部車体と、後輪を有する後部車体
とを縦軸廻りに屈折自在に連結すると共に、前輪をキン
グピン廻りに操向自在に支持し、操向ハンドルの全範囲
での回動操作に連動して前輪をキングピン廻りに操向動
作させる前輪操向シリンダと、前記全範囲の内の一定範
囲を越えた範囲での操向ハンドルの回動操作に連動して
前後部車体を縦軸廻りに屈折させる車体屈折シリンダと
を設けたことを特徴とする車輌の操向装置。(1) The front body with the front wheels and the rear body with the rear wheels are connected so as to be bendable around the longitudinal axis, and the front wheels are supported around the kingpin so that they can be steered freely, so that A front wheel steering cylinder that steers the front wheels around a kingpin in conjunction with rotational operation, and a front and rear vehicle body that operates in conjunction with rotational operation of the steering handle in a range beyond a certain range within the above-mentioned total range. A steering device for a vehicle, characterized in that it is provided with a vehicle body bending cylinder that bends a vehicle body around a longitudinal axis.