JPH09238508A - Farm tractor - Google Patents

Farm tractor

Info

Publication number
JPH09238508A
JPH09238508A JP5041596A JP5041596A JPH09238508A JP H09238508 A JPH09238508 A JP H09238508A JP 5041596 A JP5041596 A JP 5041596A JP 5041596 A JP5041596 A JP 5041596A JP H09238508 A JPH09238508 A JP H09238508A
Authority
JP
Japan
Prior art keywords
speed
control
height
rotary tiller
sensor
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
JP5041596A
Other languages
Japanese (ja)
Other versions
JP3321517B2 (en
Inventor
Satoshi Iida
聡 飯田
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.)
Kubota Corp
Original Assignee
Kubota Corp
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 Kubota Corp filed Critical Kubota Corp
Priority to JP05041596A priority Critical patent/JP3321517B2/en
Publication of JPH09238508A publication Critical patent/JPH09238508A/en
Application granted granted Critical
Publication of JP3321517B2 publication Critical patent/JP3321517B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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  • Lifting Devices For Agricultural Implements (AREA)

Abstract

PROBLEM TO BE SOLVED: To shorten the distance of a plowed part which is insufficient in plowing depth when a rotary plowing device is lowered while a tractor body travels fast. SOLUTION: This tractor is equipped with an elevation controller 40 which performs automatic plowing depth control for elevating and lowering a rotary tilling device so that the measurement signal of a grounding sensor 26 is held at a specific value and control for fast lowering in the beginning of the lowering of the rotary plowing device that is not grounded until switching height is measured by a tractor body height sensor 29 and then lowering in a speed reduced state after the switching height is reached, and also equipped with a height changing means E which sets the switching height higher and higher as the tractor speed measured by a tractor speed sensor 39 is higher and higher and a speed changing means F which makes the lowering speed in the speed reduced state higher and higher as the tractor speed measured by the speed sensor 39 is faster and faster.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【発明の属する技術分野】本発明は、走行車体に対して
アクチュエータの駆動で昇降自在にロータリ耕耘装置を
連結し、このロータリ耕耘装置の対車体高さを計測する
対車体高さセンサと、このロータリ耕耘装置の後方の地
表面を基準にした対地高さを計測する接地センサとを備
え、接地センサからの計測信号を所定値に維持するよう
アクチュエータの駆動でロータリ耕耘装置を昇降して耕
深の維持を図る自動耕深制御を行うと共に、非接地状態
のロータリ耕耘装置の下降初期には対車体高さセンサで
ロータリ耕耘装置が所定の対車体高さが計測されるまで
該ロータリ耕耘装置を高速で下降させ、この対車体高さ
に達した後には減速状態でロータリ耕耘装置を下降させ
る下降制御を行う昇降制御装置を備えた農用トラクタの
改良に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle-to-vehicle height sensor for connecting a rotary tiller to a traveling vehicle so that the rotary tiller can be moved up and down by driving an actuator, and measuring the height of the rotary tiller to the vehicle. It is equipped with a ground sensor that measures the height above the ground with respect to the ground surface behind the rotary tiller, and the rotary tiller is moved up and down by driving the actuator so that the measurement signal from the ground sensor is maintained at a predetermined value. In addition to performing automatic tillage control to maintain the rotary tiller at the beginning of descent of the rotary tiller in a non-grounded state, the rotary tiller is turned on by the height-to-body height sensor until the rotary tiller measures a predetermined height against the body. The present invention relates to an improvement of an agricultural tractor equipped with an elevating control device that descends at a high speed and, after reaching the height against the vehicle body, descends the rotary tiller in a decelerated state.

【0002】[0002]

【従来の技術】従来、上記のように構成された農用トラ
クタとして特開平4‐75506号公報に示されるもの
が存在し、この従来例ではロータリ耕耘装置の下降時に
は前述の制御を行うことによって、一定の速度で下降さ
せるものと比較してロータリ耕耘装置の耕起爪が接地す
る際のエンジンに対する過負荷を小さくすると共に、ダ
ッシングを低減し、耕起土の盛り上がり量を小さくする
という良好な面を有するものとなっている。
2. Description of the Related Art Conventionally, there is an agricultural tractor constructed as described above, which is disclosed in Japanese Patent Application Laid-Open No. 4-75506. In this conventional example, the aforementioned control is performed when the rotary tiller is lowered. Compared with the one that lowers at a constant speed, it is a good aspect to reduce overload on the engine when the plowing claw of the rotary tiller touches the ground, reduce dashing, and reduce the amount of rise of plowing soil. It has become.

【0003】[0003]

【発明が解決しようとする課題】しかし、この従来例の
制御動作では車体の走行速度に拘わらずロータリ耕耘装
置の下降速度が前述のように変化するので、例えば、高
速で走行する状態で前述の下降制御を行った場合には目
標耕深に達するまで長時間を要する結果、不充分な耕深
での耕起部分も長くなるものとなり改善の余地がある。
However, in the control operation of this conventional example, the descending speed of the rotary tiller changes as described above regardless of the traveling speed of the vehicle body, so that, for example, in the case where the vehicle is traveling at high speed, When the descending control is performed, it takes a long time to reach the target tillage depth, and as a result, the tillage portion at an insufficient tillage depth also becomes longer and there is room for improvement.

【0004】本発明の目的は、ロータリ耕耘装置での耕
起作業時に車体を高速で走行させた場合でも不充分な耕
深での耕起部分の長さを短くし得る農用トラクタを合理
的に構成する点にある。
An object of the present invention is to rationalize an agricultural tractor capable of shortening the length of a plowing part at an insufficient plowing depth even when the vehicle body is traveling at high speed during plowing work with a rotary tiller. There is a point in configuring.

【0005】[0005]

【課題を解決するための手段】本発明の第1の特徴(請
求項1)は冒頭に記したように、走行車体に対してアク
チュエータの駆動で昇降自在に連結されたロータリ耕耘
装置の対車体高さを計測する対車体高さセンサと、ロー
タリ耕耘装置の後方の耕起後の地表面を基準にした対地
高さを計測する接地センサとを備え、接地センサからの
計測信号を所定値に維持するようアクチュエータの駆動
でロータリ耕耘装置を昇降して耕深の維持を図る自動耕
深制御を行うと共に、非接地状態のロータリ耕耘装置の
下降初期には対車体高さセンサでロータリ耕耘装置が所
定の対車体高さが計測されるまで該ロータリ耕耘装置を
高速で下降させ、この対車体高さに達した後には減速状
態でロータリ耕耘装置を下降させる下降制御を行う制御
装置を備えた農用トラクタにおいて、走行車体の走行速
度を計測する速度センサを備え、この速度センサで計測
される速度が速いほど前記下降制御時において高速下降
状態から低速下降状態に切換える対車体高さの値を高い
側に変更する高さ変更手段と、このように高さ変更手段
で高い側に変更された位置からの下降でも低速走行時と
比較して下降開始からロータリ耕耘装置が接地するまで
の時間を短縮する値に設定された速度まで前記下降制御
時におけるロータリ耕耘装置の下降速度を速める速度変
更手段とを備えている点にあり、その作用は次の通りで
ある。
A first feature of the present invention (claim 1) is, as described at the beginning, a body of a rotary tiller which is connected to a traveling vehicle body by an actuator so as to be movable up and down. It is equipped with a height sensor against the vehicle body that measures the height, and a ground sensor that measures the height above the ground after plowing at the rear of the rotary tiller, and the measurement signal from the ground sensor is set to a predetermined value. The automatic tillage depth control is performed to maintain the tillage depth by raising and lowering the rotary tiller by driving the actuator so that the rotary tiller is detected by the height sensor against the vehicle body at the initial stage of descending the rotary tiller not in contact with the ground. Agricultural equipment provided with a control device for lowering the rotary tiller at a high speed until a predetermined height against the vehicle body is measured and, after reaching the height against the vehicle body, lowering the rotary tiller in a decelerating state. The tractor is provided with a speed sensor for measuring the traveling speed of the traveling vehicle body, and the higher the speed measured by this speed sensor, the higher the value of the height against vehicle body that is switched from the high speed descending state to the low speed descending state during the descending control Even if the height changing means is changed to the height changing means and the position is changed to the higher side by the height changing means, the time from the start of the descending until the rotary tiller touches the ground is shortened as compared with the case of low speed traveling. A speed changing means for increasing the descending speed of the rotary tiller during the descending control up to the speed set to the value is provided, and its operation is as follows.

【0006】本発明の第2の特徴(請求項2)は、前記
下降制御でロータリ耕耘装置を下降させて前記自動耕深
制御に切り換わった際に、該自動耕深制御における上昇
制御を設定時間だけ阻止する規制手段を備えると共に、
前記速度センサで計測される速度が速いほど、この規制
手段における設定時間を短くする時間変更手段を備えて
いる点にあり、その作用は次の通りである。
A second feature of the present invention (claim 2) is to set the raising control in the automatic tilling depth control when the rotary tiller is lowered by the lowering control to switch to the automatic tilling depth control. In addition to being equipped with regulation means to block only time,
The faster the speed measured by the speed sensor is, the more the time changing means for shortening the set time in the restricting means is provided, and the operation thereof is as follows.

【0007】本発明の第3の特徴(請求項3)は、前記
アクチュエータが油圧シリンダで構成されると共に、前
記速度変更手段が、前記速度センサで計測される速度が
速いほど油圧シリンダに対する制御弁の作動油の単位時
間内の給排量を増大させる制御動作を行うよう構成され
ている点にあり、その作用は次の通りである。
A third feature of the present invention (claim 3) is that the actuator comprises a hydraulic cylinder and the speed changing means controls the hydraulic cylinder as the speed measured by the speed sensor increases. Is configured to perform a control operation for increasing the supply / discharge amount of the hydraulic oil within a unit time, and its operation is as follows.

【0008】〔作用〕上記第1の特徴によると、ロータ
リ耕耘装置を下降させる際には速度センサで計測される
速度が速いほど、高速下降状態から低速下降状態に切換
える対車体高さの値を高さ変更手段が高い側に変更する
と共に、速めた速度でロータリ耕耘装置を下降させ、こ
の下降速度が低速走行時と比較して下降開始から該ロー
タリ耕耘装置が接地するまでの時間を短縮する値に設定
するので低速走行時と比較して短時間のうちにロータリ
耕耘装置が接地するものとなり、不充分な耕深での耕起
部分が長くなる現象を抑制できる。又、車体の走行速度
が速くなるほど低速下降状態での下降速度が速くなるの
ものの、高速下降状態から低速下降状態への切換わり位
置を高い側に変更して下降ストロークを大きくすること
で、速度の切換わりの後におけるロータリ耕耘装置の動
慣性による影響を小さくして所望の減速速度での下降を
可能にするものとなる。
[Operation] According to the first feature described above, when lowering the rotary tiller, the higher the speed measured by the speed sensor, the higher the value of the height relative to the vehicle body that is switched from the high speed descending state to the low speed descending state. While changing the height changing means to a higher side, the rotary tiller is lowered at a faster speed, and this lowering speed shortens the time from the start of descending until the rotary tiller touches the ground as compared with low speed traveling. Since the value is set, the rotary tiller is brought into contact with the ground in a short time as compared with the case of low speed traveling, and it is possible to suppress the phenomenon that the plowing part becomes long at an insufficient plowing depth. Further, although the lowering speed in the low speed descending state becomes faster as the traveling speed of the vehicle body becomes faster, by changing the switching position from the high speed descending state to the low speed descending state to the higher side and increasing the descending stroke, The influence of the dynamic inertia of the rotary cultivator after the changeover is reduced to enable the descending at a desired deceleration speed.

【0009】上記第2の特徴によると、ロータリ耕耘装
置の下降によって自動耕深制御に切り換わった直後に
は、接地センサの計測結果によって見掛け上ロータリ耕
耘装置が目標耕深に達しているものの(実耕深は目標耕
深より深いものとなっている)、実際には耕起初期の盛
り上りが不充分な圃場面を接地センサが計測しているの
で車体の走行で耕起後の盛り上り状態の圃場面が形成さ
れるまでは、ロータリ耕耘装置の対地高さを維持するこ
とが好ましいが、走行速度に拘わらず一定の時間上昇制
御を規制するものでは目標耕深より深い耕起部が長く形
成されるものとなる。本発明によれば、走行速度を速く
した場合には走行速度が速いほど自動耕深制御における
上昇制御を規制する規制手段の規制時間を短くすること
によって、耕起により充分に盛り上がった圃場面を接地
センサが計測した状態での自動耕深制御への切換わりを
短時間行い得るものとなる。
According to the second feature, although the rotary tiller apparatus apparently reaches the target tilling depth by the measurement result of the ground sensor immediately after the automatic tiller depth control is switched by the lowering of the rotary tiller, ( The actual plowing depth is deeper than the target plowing depth.) Actually, the grounding sensor measures the field scene where the rise in the early stage of plowing is insufficient. Until the field scene of the state is formed, it is preferable to maintain the ground height of the rotary tiller, but in the case of regulating the constant time rise control regardless of the traveling speed, the tilling part deeper than the target tillage depth is required. It will be formed long. According to the present invention, when the traveling speed is increased, the regulation time of the regulation means for regulating the rising control in the automatic plowing depth control is shortened as the traveling speed becomes faster, so that the field scene sufficiently swelled by plowing can be set. It becomes possible to switch to the automatic tilling depth control in a short time while the ground sensor measures.

【0010】上記第3の特徴によると、速度変更手段が
アクチュエータとしての油圧シリンダに対する制御弁の
作動油の単位時間内の給排量を車体の走行速度が速いほ
ど増大させるのよう制御するので走行速度が増大した場
合にも充分な量の作動油の給排で必要とするロータリ耕
耘装置の作動を可能にする。
According to the third feature, the speed changing means controls the supply / discharge amount of the working oil of the control valve to the hydraulic cylinder as the actuator within a unit time so as to increase as the traveling speed of the vehicle body increases. Even when the speed is increased, it is possible to operate the rotary tiller as required by supplying and discharging a sufficient amount of hydraulic oil.

【0011】[0011]

【発明の実施の形態】以下、本発明の実施の形態を図面
に基づいて説明する。図1に示すように、前車輪1及び
後車輪2を備えた車体3の前部にエンジン4を配置し、
このエンジン4からの動力が伝えられるミッションケー
ス5を車体3の後部に配置し、このミッションケース5
の上方位置で左右のリヤフェンダー6の中間位置に運転
座席7を配置し、この運転座席7の前部にステアリング
ハンドル8を配置すると共に、車体3の後端位置に2点
リンク機構9を介してロータリ耕耘装置10を昇降自
在、かつ、ローリング自在に連結し、又、ミッションケ
ース5の上部位置に配置した単動型のリフトシリンダ1
1(請求項1のアクチュエータの一例)の駆動で昇降操
作される左右一対のリフトアーム12と2点リンク機構
9を左右のリフトロッド13を介して連結することで吊
下げ状態に支持し、更に、一方のリフトロッド13に複
動型のローリングシリンダ14を介装することで、ロー
タリ耕耘装置10の駆動昇降と、前後向きのローリング
軸芯X周りでの駆動ローリングとが自在な農用トラクタ
を構成する。
Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, an engine 4 is arranged at a front part of a vehicle body 3 having a front wheel 1 and a rear wheel 2,
A transmission case 5 to which the power from the engine 4 is transmitted is disposed at the rear of the vehicle body 3.
A driver's seat 7 is arranged at an intermediate position between the left and right rear fenders 6 above the vehicle, a steering handle 8 is arranged in front of the driver's seat 7, and a two-point link mechanism 9 is provided at a rear end position of the vehicle body 3. A single-acting lift cylinder 1 in which a rotary cultivator 10 is connected to be movable up and down and to be rolled, and is arranged at an upper position of the mission case 5.
A pair of left and right lift arms 12 that are vertically moved by driving 1 (an example of the actuator of claim 1) and a two-point link mechanism 9 are connected to each other via left and right lift rods 13 to support them in a suspended state. By mounting a double-acting rolling cylinder 14 on one of the lift rods 13, an agricultural tractor which can freely drive and elevate the rotary tiller 10 and drive and roll around the rolling axis X in the front-rear direction is configured. To do.

【0012】図2に示すように、ロータリ耕耘装置10
の駆動昇降、及び、駆動ローリングを行うための油圧系
は、前記エンジン4で駆動される油圧ポンプPと、流量
制御用のフロープライオリティ弁17と、このフロープ
ライオリティ弁17からの制御流を前記ローリングシリ
ンダ14に供給するローリング電磁弁18と、フロープ
ライオリティ弁17からの余剰流を前記リフトシリンダ
11に供給する、あるいは、リフトシリンダ11からの
油を排出する電磁比例制御弁Vとを有して成り、この電
磁比例制御弁Vは上昇制御用の第1弁19と、この第1
弁19を開閉操作するパイロット圧制御用の第2弁20
と、下降制御用の第3弁21と、この第3弁21を開閉
操作するパイロット圧制御用の第4弁22と、リリーフ
弁23とで成り、ロータリ耕耘装置10を上昇制御する
場合には第2弁20の電磁ソレノイド20Aに電流を供
給すると共に、この供給電流の調節により、第1弁19
に作用するパイロット圧が変化する結果、この電流値と
比例する弁の開度が得られ開度に比例した上昇速度を得
るものとなっており、又、ロータリ耕耘装置10を下降
制御する場合には第4弁22の電磁ソレノイド22Aに
電流を供給すると共に、この供給電流の調節により、第
2弁20に作用するパイロット圧が変化する結果、この
電流値と比例する弁の開度が得られ開度に比例した下降
速度を得るものとなっている。
As shown in FIG. 2, a rotary tiller 10 is provided.
The hydraulic system for driving up and down and driving rolling includes a hydraulic pump P driven by the engine 4, a flow priority valve 17 for flow control, and a control flow from the flow priority valve 17 for rolling. It comprises a rolling solenoid valve 18 for supplying to the cylinder 14 and an electromagnetic proportional control valve V for supplying surplus flow from the flow priority valve 17 to the lift cylinder 11 or discharging oil from the lift cylinder 11. The electromagnetic proportional control valve V includes a first valve 19 for ascending control,
Second valve 20 for pilot pressure control for opening and closing valve 19
And a third valve 21 for lowering control, a fourth valve 22 for pilot pressure control for opening and closing the third valve 21, and a relief valve 23. A current is supplied to the electromagnetic solenoid 20A of the second valve 20, and the first valve 19 is controlled by adjusting the supplied current.
As a result of the change in the pilot pressure acting on the valve, an opening of the valve that is proportional to this current value is obtained, and an ascending speed that is proportional to the opening is obtained. Further, when the rotary tiller 10 is controlled to descend. Supplies a current to the electromagnetic solenoid 22A of the fourth valve 22, and by adjusting the supplied current, the pilot pressure acting on the second valve 20 changes, and as a result, an opening degree of the valve proportional to this current value is obtained. The descending speed proportional to the opening is obtained.

【0013】この農用トラクタではロータリ耕耘装置1
0を圃場面(地面)を基準にした所定高さに維持する自
動耕深制御と、車体3を基準にした所定の高さまでロー
タリ耕耘装置10を昇降するポジション制御と、前後向
き姿勢のローリング軸芯X周りでロータリ耕耘装置10
を所定のローリング姿勢に維持するローリング制御との
3種の制御と、この3種の制御に優先してロータリ耕耘
装置10を所定の対車体高さまで上昇させると同時に該
ロータリ耕耘装置10を決められたローリング姿勢に設
定維持する強制上昇制御とを行う制御系を備えている。
In this agricultural tractor, the rotary tiller 1
Automatic tillage depth control for maintaining 0 at a predetermined height based on a field scene (ground), position control for raising and lowering the rotary tillage device 10 to a predetermined height based on the vehicle body 3, and a rolling shaft in a front-back posture. Rotary tilling device 10 around core X
And the rolling tillage device 10 is maintained at a predetermined rolling posture, and the rotary tillage device 10 is raised to a predetermined height with respect to the vehicle body in preference to the three types of control. And a control system for performing forced ascent control for setting and maintaining the rolling posture.

【0014】又、自動耕深制御を行うよう、運転座席7
の右側のリヤフェンダー6の上面にコントロールボック
ス24を備え、このコントロールボックス24にポテン
ショメータ型の耕深設定器25を備え、ロータリ耕耘装
置10の上面に対して該ロータリ耕耘装置10の後部位
置で横軸芯Y周りで揺動自在に構成された後カバー10
Aの揺動量から耕起後の圃場面(地表面)を基準にした
該ロータリ耕耘装置10の対地高さを計測するポテンシ
ョメータ型の接地センサ26を備えており、又、ポジシ
ョン制御を行うよう、運転座席7の右側部に配置した昇
降レバー27の基端部にはポテンショメータ型のポジシ
ョン設定器28を備え、リフトアーム12の基端部には
該リフトアーム12の揺動量からロータリ耕耘装置10
の対車体高さを計測するポテンショメータ型のリフトア
ームセンサ29(請求項1の対車体高さセンサの一例)
を備えており、又、ローリング制御を行うよう、前記コ
ントールボックス24にはポテンショメータ型のローリ
ング角設定器30を備え、車体3の後端部に該車体3の
左右方向へのローリング量を電気的に計測するローリン
グセンサ31を備え、前記ローリングシリンダ14の近
傍位置には該ローリングシリンダ14の伸縮量を計測す
るストロークセンサ32を備え、又、強制上昇制御を行
うよう、図3に示す如く、前記ステアリングハンドル8
のポスト部33には上下方向に操作自在、かつ、中立位
置Nに復元するよう付勢すと共に、上昇位置Uと下降位
置Dとに操作自在な強制昇降レバー34を配置し、この
レバー34の基端部に該レバー34の操作方向を検出す
る強制昇降スイッチ35を備えている。更に、この農用
トラクタでは図4に示す如く、ミッションケース5に内
蔵したギヤ式の変速装置36から後車輪2に動力を伝え
る差動装置37の入力軸38の回転速度から車体の走行
速度を計測するようギヤの歯に感応するピックアップ型
の速度センサ39を備え、この速度センサ39は後述す
るように強制上昇制御で略上限まで上昇させたロータリ
耕耘装置10を下降させて自動耕深制御に切換える際に
制御動作の変更と、自動耕深制御の制御感度の設定に用
いられる。
In addition, the driver's seat 7 is controlled so that automatic plowing depth control is performed.
The control box 24 is provided on the upper surface of the rear fender 6 on the right side of the vehicle, and the control box 24 is provided with a potentiometer-type tillage depth setting device 25. Rear cover 10 configured to be swingable about axis Y
A potentiometer-type grounding sensor 26 that measures the ground height of the rotary tillage device 10 based on the field scene (ground surface) after plowing from the swing amount of A is provided. At the base end of a lift lever 27 disposed on the right side of the driver's seat 7 is provided a potentiometer type position setting device 28, and at the base end of the lift arm 12, a rotary tilling device 10 is provided based on the swing amount of the lift arm 12.
Type lift arm sensor 29 for measuring the height of the vehicle relative to the vehicle (an example of the height sensor relative to the vehicle of claim 1)
In order to perform rolling control, the control box 24 is provided with a potentiometer-type rolling angle setter 30, and a rear end portion of the vehicle body 3 is provided with an electric amount of rolling in the left-right direction of the vehicle body 3. Is equipped with a rolling sensor 31 for measuring, and a stroke sensor 32 for measuring the amount of expansion and contraction of the rolling cylinder 14 is provided in the vicinity of the rolling cylinder 14, and as shown in FIG. Steering wheel 8
In the post portion 33, a forcible elevating lever 34 that is operable in the vertical direction and is biased to restore to the neutral position N and that is operable in the ascending position U and the descending position D is arranged. The base end is provided with a forced elevating switch 35 for detecting the operating direction of the lever 34. Further, in this agricultural tractor, as shown in FIG. 4, the traveling speed of the vehicle body is measured from the rotation speed of the input shaft 38 of the differential device 37 that transmits power to the rear wheels 2 from the gear type transmission device 36 incorporated in the mission case 5. A speed sensor 39 of a pickup type that is sensitive to the teeth of the gear is provided, and the speed sensor 39 lowers the rotary tiller 10 that has been raised to approximately the upper limit by the forcible raising control and switches to the automatic tilling depth control as described later. At this time, it is used for changing the control operation and setting the control sensitivity of the automatic plowing depth control.

【0015】図5に示すように、前記設定系からの信
号、及び、フィードバック系からの信号が入力する系、
及び、電磁比例制御弁V、ローリング電磁弁18に対す
る制御信号を出力する系を備えて制御装置40が構成さ
れている。尚、自動耕深制御の概要は耕深設定器25で
設定された目標耕深の値に向けて接地センサ26からの
計測値が変化するようリフトシリンダ11を駆動してロ
ータリ耕耘装置10を昇降させると共に、目標耕深を基
準に設定された不感帯の信号域に接地センサ26からの
計測値が達するとロータリ耕耘装置10の昇降を停止さ
せるよう動作を設定したものであり、又、ポジション制
御の概要はポジション設定器28で設定された目標高さ
の値に向けてリフトアームセンサ29からの信号が変化
するようリフトシリンダ11の駆動でロータリ耕耘装置
10を昇降させると共に、目標高さを基準に設定された
不感帯の信号域にリフトアームセンサ29からの信号が
達するとロータリ耕耘装置10の昇降を停止させる動作
を設定したものであり、又、ローリング制御の概要はロ
ーリング角設定器30で設定されたロータリ耕耘装置1
0の対地ローリング角と、ローリングセンサ31で計測
された車体3の左右方向へのローリング角とに基づいて
ローリングシリンダ14の目標長さを求め、この目標長
さの値に向けてストロークセンサ32で計測される値が
変化するようローリングシリンダ14を駆動すると共
に、目標長さを基準に設定された不感帯の信号域にスト
ロークセンサ32からの信号が達するとローリング制御
を停止させる動作を設定したものであり、強制上昇制御
の概要は強制昇降レバー34を上昇位置Uに操作するこ
とで予め設定された上限値を基準に設定した不感帯の信
号域にリフトアームセンサ29からの信号が達するまで
ロータリ耕耘装置10を上昇させると共に、ローリング
制御によってロータリ耕耘装置10が車体3に対して傾
斜した状態にある場合には車体3に対して傾斜のない姿
勢に達するまでローリングシリンダ14を駆動するもの
であり、この強制昇降レバー34を下降位置Dに操作す
ると強制上昇制御を行う以前の高さまで(自動耕深制御
状態で強制上昇が行われた場合には自動耕深制御が行わ
れる高さまで)ロータリ耕耘装置10を下降させる制御
を行うものとなっている。
As shown in FIG. 5, a system to which the signal from the setting system and the signal from the feedback system are input,
The control device 40 is configured to include a system that outputs a control signal to the electromagnetic proportional control valve V and the rolling electromagnetic valve 18. In addition, the outline of the automatic tilling depth control is that the lift cylinder 11 is driven so that the rotary tiller 10 is moved up and down so that the measured value from the ground sensor 26 changes toward the target tilling depth value set by the tiller depth setting device 25. At the same time, when the measured value from the ground sensor 26 reaches the signal zone of the dead zone set with the target tillage depth as a reference, the operation is set so as to stop the lifting and lowering of the rotary tiller 10, and the position control is performed. The outline is that the lift tiller 11 is driven to raise and lower the rotary tiller 10 so that the signal from the lift arm sensor 29 changes toward the target height value set by the position setter 28, and the target height is used as a reference. When the signal from the lift arm sensor 29 reaches the signal zone of the set dead zone, the operation of stopping the lifting and lowering of the rotary tiller 10 is set. Overview-ring control rotary tiller 1 set by the rolling angle setter 30
The target length of the rolling cylinder 14 is obtained based on the ground rolling angle of 0 and the horizontal rolling angle of the vehicle body 3 measured by the rolling sensor 31, and the stroke sensor 32 moves toward this target length value. The operation is such that the rolling cylinder 14 is driven so that the measured value changes, and the rolling control is stopped when the signal from the stroke sensor 32 reaches the signal range of the dead zone set based on the target length. The outline of the forced raising control is to operate the forced raising / lowering lever 34 to the raising position U until the signal from the lift arm sensor 29 reaches the dead zone signal range set based on the preset upper limit value. When the rotary tiller 10 is tilted with respect to the vehicle body 3 by the rolling control while raising 10 Is to drive the rolling cylinder 14 until it reaches a posture without inclination with respect to the vehicle body 3, and when the forcible lifting lever 34 is operated to the lowered position D, the height before the forced lifting control is performed (the automatic plowing depth control When the forcible ascent is performed in this state, control is performed to lower the rotary tiller 10 to a height at which automatic tillage depth control is performed).

【0016】又、この農用トラクタでは時速3〜4キロ
メータ/時間の比較的高速の走行状態(従来は1.8キ
ロメータ/時間程度が限界)での自動耕深制御が可能に
構成され、この自動耕深制御での耕起作業時に車体3が
畦際に達し、強制昇降レバー34の操作でロータリ耕耘
装置10を上昇させ車体3を反転させてロータリ耕耘装
置10を下降させる操作を行った際にはエンジン4に過
負荷を作用させない状態で、かつ、作業能率を低下させ
ず自動耕深制御を再開する耕深まで迅速にロータリ耕耘
装置10を下降させる制御動作を行うように構成されて
いる。
Further, this agricultural tractor is constructed so as to be capable of automatic tilling depth control in a relatively high-speed traveling state of 3 to 4 km / hour (the conventional limit is about 1.8 km / hour). When the vehicle body 3 reaches a ridge at the time of plowing work under the tilling depth control, and the operation of the forcible lifting lever 34 raises the rotary tilling device 10 to invert the vehicle body 3 and lower the rotary tilling device 10. Is configured to perform a control operation of rapidly lowering the rotary tiller 10 to a working depth in which the working efficiency is not reduced and the automatic working depth control is restarted without reducing the overload.

【0017】つまり、図6のフローチャートに示すよう
に、ロータリ耕耘装置10を強制的に上昇させ、車体3
の旋回が終了して強制昇降レバー34を下降位置Dに操
作した場合には、速度センサ39の計測結果に基づいて
制御パラメータをセットすると共に、ロータリ耕耘装置
10を強制的に上昇させる以前の自動耕深制御時に計測
した接地センサ26からの計測値とリフトアームセンサ
29からの計測値とに基づいた所定の値を、前記制御パ
ラメータに基づいて演算することで切換高さをセット
し、更に、電磁比例制御弁Vを下降位置の全開にセット
してロータリ耕耘装置10の下降を開始する(#101
〜#103ステップ)。
That is, as shown in the flow chart of FIG. 6, the rotary tiller 10 is forcibly raised and the vehicle body 3
When the forced raising / lowering lever 34 is operated to the lowered position D after the turning of No. 1 is completed, the control parameter is set based on the measurement result of the speed sensor 39, and the rotary tiller 10 is forcibly lifted automatically. The switching height is set by calculating a predetermined value based on the measured value from the ground sensor 26 and the measured value from the lift arm sensor 29 during the tilling depth control, based on the control parameter. The electromagnetic proportional control valve V is set to the fully open position at the lowered position and the descent of the rotary tiller 10 is started (# 101
~ Step # 103).

【0018】この切換高さは、ロータリ耕耘装置10を
高速下降状態から減速下降状態に切換えるため車体3を
基準にして設定された高さであり、自動耕深制御時に計
測した接地センサ26からの計測値とリフトアームセン
サ29から車体3と圃場面との相対距離を求める処理を
行い、この処理結果と速度センサ39に基づく車体3の
走行速度とに基づいて車速が高速であるほど切換高さを
高くセットするよう、制御パラメータに基づく演算を行
うことで、圃場面に車輪1,2が沈み込む状態であって
もロータリ耕耘装置10の耕起爪10Bが圃場面から上
方に離間した位置から減速を開始するものとなってい
る。このように車速が速いほど切換高さを高く設定する
ための制御動作としての#102ステップで請求項1の
高さ変更手段Eが構成されている。
This switching height is a height set with reference to the vehicle body 3 in order to switch the rotary tiller 10 from the high speed descending state to the decelerating descending state, and is measured from the ground sensor 26 during the automatic plowing depth control. A process for obtaining the relative distance between the vehicle body 3 and the farm scene is performed from the measured value and the lift arm sensor 29. Based on the processing result and the traveling speed of the vehicle body 3 based on the speed sensor 39, the higher the vehicle speed, the higher the switching height. By performing the calculation based on the control parameter so that the value is set high, even if the wheels 1 and 2 sink in the field scene, the tillage claw 10B of the rotary tiller 10 is separated from the position above the field scene. It is supposed to start decelerating. In this way, the height changing means E of claim 1 is constituted by step # 102 as a control operation for setting the switching height higher as the vehicle speed becomes faster.

【0019】このように、ロータリ耕耘装置10が高速
で下降を開始した後にはリフトアームセンサ29からの
信号を入力してロータリ耕耘装置10が切換高さに達し
たかを判別すると共に、切換高さに達した際には、前記
制御パラメータに対応する開度まで電磁比例制御弁Vを
絞り操作して減速を開始する(#104〜#106ステ
ップ)。
As described above, after the rotary tiller 10 starts descending at a high speed, a signal from the lift arm sensor 29 is input to determine whether the rotary tiller 10 has reached the switching height, and at the same time, the switching height is increased. When it reaches the predetermined value, the electromagnetic proportional control valve V is throttled to the opening degree corresponding to the control parameter to start deceleration (steps # 104 to # 106).

【0020】このように減速状態で下降させる理由はエ
ンジン4に対する負荷を急激に増大させないためであ
り、又、このように減速された速度は走行速度が高速で
あるほど高速化するようにセットしてあり、切換高さを
高くセットするものでありながらロータリ耕耘装置10
の下降開始から接地までの時間を、車体3の走行速度が
高速であるほど短縮するよう減速状態での下降速度の値
を決めることによって不充分な耕深での耕起跡の長さを
短くするものとなっている。尚、このように走行速度が
速いほど減速下降状態での下降速度を高める制御動作と
しての#106ステップで請求項1の速度変更手段Fが
構成されている。
The reason for lowering the speed in the decelerating state is that the load on the engine 4 is not sharply increased, and the speed thus decelerated is set so as to increase as the traveling speed becomes higher. The rotary cultivator 10 has a high switching height.
The length of the plowing trace at an insufficient plowing depth is shortened by determining the value of the descending speed in the deceleration state so that the time from the start of descending of the vehicle to the touchdown becomes shorter as the traveling speed of the vehicle body 3 becomes faster. It is supposed to do. The speed changing means F of claim 1 is constituted by step # 106 as a control operation for increasing the descending speed in the decelerated descending state as the traveling speed becomes faster.

【0021】次に、下降によってロータリ耕耘装置10
の耕起爪10Bが圃場面に接触した後には、ロータリ耕
耘装置10の後方の圃場面に耕起によって盛り上がった
部位が形成され、この部位に該ロータリ耕耘装置10の
後カバー10Aが接触して持ち上げ方向に揺動すること
から、接地センサ26からの信号を入力して該ロータリ
耕耘装置10が耕深設定器25で設定された耕深まで下
降したかを該接地センサ26からの信号を入力して判別
し、この信号が自動耕深制御における目標値に達した
(厳密には目標値を基準に設定された不感帯の域内に達
した)際には、上昇制御を前記制御パラメータに対応す
る時間だけ行わない自動耕深制御を開始すると共に、こ
の時間が経過すると自動耕深制御に移行するようになっ
ている(#107〜#109ステップ、#200ステッ
プ)。尚、この制御動作のうち#109ステップで、請
求項2において自動耕深制御に切換わる直前にロータリ
耕耘装置10の上昇作動を阻止する規制手段Gと、走行
速度が速いほど規制時間を短くする時間変更手段Hとが
構成されている。
Next, the rotary tiller 10 is moved downward.
After the plowing claw 10B of No. 1 comes into contact with the field scene, a region raised by plowing is formed in the field scene behind the rotary tiller 10, and the rear cover 10A of the rotary tiller 10 comes into contact with this site. Since it swings in the lifting direction, a signal from the ground sensor 26 is input to determine whether the rotary tiller 10 has descended to the working depth set by the working depth setting device 25. Then, when this signal reaches the target value in the automatic tilling depth control (strictly, it reaches the dead zone set based on the target value), the ascending control corresponds to the control parameter. The automatic tilling depth control, which is not performed only for the time, is started, and when this time elapses, the automatic tilling depth control is switched to (steps # 107 to # 109, step # 200). In step # 109 of this control operation, the restriction means G for preventing the rising operation of the rotary tiller 10 immediately before switching to the automatic tillage depth control in claim 2, and the restriction time shortened as the traveling speed increases. A time changing means H is configured.

【0022】又、自動耕深制御で上昇制御を規制する時
間は、車体3の走行速度が1.8キロメータ/時間の低
速走行時には2秒に設定され、この走行速度が高速化す
るほどこの規制時間が短縮されるよう走行速度に反比例
する関係で設定されている。
Further, the time for restricting the ascending control by the automatic plowing depth control is set to 2 seconds when the vehicle body 3 travels at a low speed of 1.8 km / hour, and the higher the traveling speed, the more restricted the travel speed is. It is set to be inversely proportional to the traveling speed so that the time can be shortened.

【0023】図7のフローチャートに示すように、自動
耕深制御では耕深設定器25からの信号を入力して目標
耕深を算出すると共に(#201,#202ステッ
プ)、車速センサからの信号を入力して前記目標耕深を
基準に形成される不感帯の幅を車速が高速であるほど広
くするよう車速と正比例の関係でセットし、又、電磁比
例制御弁Vを介して給排される作動油量を車速が速くな
るほど低減する関係でセットする(#203〜#205
ステップ)。
As shown in the flow chart of FIG. 7, in the automatic tilling depth control, the signal from the tilling depth setting device 25 is input to calculate the target tilling depth (steps # 201, # 202), and the signal from the vehicle speed sensor is used. To set the width of the dead zone formed on the basis of the target plowing depth in proportion to the vehicle speed so that it becomes wider as the vehicle speed becomes higher, and is also discharged and supplied via the electromagnetic proportional control valve V. Set the hydraulic oil amount so that it decreases as the vehicle speed increases (# 203 to # 205).
Steps).

【0024】このように車速が高速化するほど不感帯の
幅を広くセットし、車速が高速化するほどリフトシリン
ダ11に対して給排する作動油量を制限する理由は、高
速走行時においてはロータリ耕耘装置10を高速で昇降
させることが圃場面に対する追従性が向上させる面で理
想であるが、重量物であるロータリ耕耘装置1を高速で
昇降する制御は困難な面があり、しかも、オーバシュー
トや制御遅れに起因してハンチングを発生する面もあ
り、これらの不都合を解消する目的から前述のように不
感帯の幅を広くセットし、リフトシリンダに対して給排
する作動油量を制限することで制御感度を低下させ、低
速で昇降を行いハンチングの発生も回避している。
The reason for setting the width of the dead zone wider as the vehicle speed increases and limiting the amount of hydraulic oil supplied to and discharged from the lift cylinder 11 as the vehicle speed increases is that the rotary is used during high-speed traveling. Although it is ideal to raise and lower the tiller 10 at high speed in order to improve the followability to the field scene, it is difficult to control the rotary tiller 1, which is a heavy object, to move up and down at high speed, and there is an overshoot. Also, hunting may occur due to control delay, and for the purpose of eliminating these inconveniences, set the width of the dead zone wide as described above to limit the amount of hydraulic oil supplied to and discharged from the lift cylinder. The control sensitivity is lowered by and the hunting is avoided by moving up and down at low speed.

【0025】次に、接地センサ26からの信号を入力
し、この信号が不感帯で設定された信号域に含まれるか
を判断し、含まれない場合には接地センサ26からの信
号が不感帯の側に変化するよう電磁比例制御弁Vを介し
てリフトシリンダ11を駆動することでロータリ耕耘装
置10の昇降を行い、接地センサ26からの信号が不感
帯の信号域に含まれる状態に達すると昇降制御を停止す
るものとなっている(#206〜#208ステップ)。
Next, the signal from the ground sensor 26 is input, and it is judged whether this signal is included in the signal range set in the dead zone. If not, the signal from the ground sensor 26 is located in the dead zone. Driven by the lift cylinder 11 via the electromagnetic proportional control valve V, the rotary tiller 10 is moved up and down, and when the signal from the ground sensor 26 reaches a state included in the signal zone of the dead zone, the elevator control is performed. It is to be stopped (steps # 206 to # 208).

【0026】尚、この昇降作動時には前述のように不感
帯を設定し、作動油量も設定していることから車速が高
速であるほど制御感度が鈍く、制御動作も低速になる。
Since the dead zone is set and the amount of hydraulic oil is set during the ascending / descending operation, the control sensitivity becomes slower and the control operation becomes slower as the vehicle speed becomes higher.

【0027】〔別実施の形態〕本発明は上記実施の形態
以外に、例えば、切換高さを設定するために圃場面に対
する車輪の沈み込み量を計測する専用のセンサを用いる
こともが可能であり、又、ロータリ耕耘装置の下降時に
切換高さに達した際には予め設定された特性で下降速度
を減ずるよう弁の開度を徐々に閉じ操作するよう制御動
作を設定することも可能である。
[Other Embodiments] In addition to the above-described embodiments, the present invention can use, for example, a dedicated sensor for measuring the amount of subsidence of the wheel with respect to the field scene in order to set the switching height. It is also possible to set the control operation to gradually close the opening of the valve so as to reduce the descending speed with a preset characteristic when the switching height is reached when the rotary tiller descends. is there.

【0028】[0028]

【発明の効果】従って、ロータリ耕耘装置での耕起作業
時に車体を高速で走行させた場合でも不充分な耕深での
耕起部分の長さを短くして迅速に適正な耕深での耕起作
業に移行可能な農用トラクタが合理的に構成された(請
求項1)。又、下降速度の高速化によってロータリ耕耘
装置が短時間のうちに適正な耕深に達する良好な面を活
かして迅速に自動耕深制御に切換えるものとなり(請求
項2)、作動油の給排量の変更で走行速度の増大にも対
応したロータリ耕耘装置の昇降制御を可能にするものと
なった(請求項3)。
Therefore, even when the vehicle body is traveling at a high speed during the plowing work with the rotary tiller, the plowing portion is shortened at an insufficient plowing depth to quickly and properly plowing. An agricultural tractor that can be transferred to plowing work has been rationally constructed (claim 1). Further, by increasing the descending speed, the rotary tiller can quickly switch to the automatic plowing depth control by taking advantage of the good surface of reaching the proper plowing depth in a short time (Claim 2). By changing the amount, it becomes possible to control the raising and lowering of the rotary cultivator which corresponds to the increase of the traveling speed (claim 3).

【0029】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。
In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration of the attached drawings.

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

【図1】農用トラクタの側面図FIG. 1 is a side view of an agricultural tractor.

【図2】昇降用、ローリング用の油圧回路図[Fig. 2] Hydraulic circuit diagram for lifting and rolling

【図3】強制昇降レバーの配置を示す側面図FIG. 3 is a side view showing the arrangement of the forcible lifting lever.

【図4】速度センサの配置を示す伝動系の概略図FIG. 4 is a schematic diagram of a transmission system showing an arrangement of speed sensors.

【図5】制御系のブロック回路図FIG. 5 is a block circuit diagram of a control system.

【図6】下降制御動作のフローチャートFIG. 6 is a flowchart of a descent control operation.

【図7】自動耕深制御のフローチャートFIG. 7: Flow chart of automatic plowing depth control

【符号の説明】[Explanation of symbols]

3 走行車体 10 ロータリ耕耘装置 11 アクチュエータ 26 接地センサ 29 対車体高さセンサ 39 速度センサ 40 昇降制御装置 E 高さ変更手段 F 速度変更手段 G 規制手段 H 時間変更手段 V 制御弁 3 Traveling vehicle 10 Rotary tiller 11 Actuator 26 Grounding sensor 29 Height sensor against vehicle 39 Speed sensor 40 Lifting control device E Height changing means F Speed changing means G Regulation means H Time changing means V Control valve

Claims (3)

【特許請求の範囲】[Claims] 【請求項1】 走行車体(3)に対してアクチュエータ
(11)の駆動で昇降自在にロータリ耕耘装置(10)
を連結し、このロータリ耕耘装置(10)の対車体高さ
を計測する対車体高さセンサ(29)と、このロータリ
耕耘装置(10)の後方の耕起後の地表面を基準にした
対地高さを計測する接地センサ(26)とを備え、接地
センサ(26)からの計測信号を所定値に維持するよう
アクチュエータ(11)の駆動でロータリ耕耘装置(1
0)を昇降して耕深の維持を図る自動耕深制御を行うと
共に、非接地状態のロータリ耕耘装置(10)の下降初
期には対車体高さセンサ(29)でロータリ耕耘装置
(10)が所定の対車体高さが計測されるまで該ロータ
リ耕耘装置(10)を高速で下降させ、この対車体高さ
に達した後には減速状態でロータリ耕耘装置(10)を
下降させる下降制御を行う制御装置(40)を備えた農
用トラクタであって、 走行車体の走行速度を計測する速度センサ(39)を備
え、この速度センサ(39)で計測される速度が速いほ
ど前記下降制御時において高速下降状態から低速下降状
態に切換える対車体高さの値を高い側に変更する高さ変
更手段(E)と、このように高さ変更手段(E)で高い
側に変更された位置からの下降でも低速走行時と比較し
て下降開始からロータリ耕耘装置(10)が接地するま
での時間を短縮する値に設定された速度まで前記下降制
御時におけるロータリ耕耘装置(10)の下降速度を速
める速度変更手段(F)とを備えている農用トラクタ。
1. A rotary tiller (10) which is movable up and down by driving an actuator (11) with respect to a traveling vehicle body (3).
And a height sensor (29) for measuring the height of the rotary tiller (10) with respect to the vehicle body, and a ground surface based on the ground surface after plowing behind the rotary tiller (10). A grounding sensor (26) for measuring the height, and the rotary tiller (1) is driven by driving the actuator (11) so as to maintain the measurement signal from the grounding sensor (26) at a predetermined value.
0) is moved up and down to maintain the tilling depth, and at the beginning of the descent of the rotary tiller (10) in the non-grounded state, the rotary tiller (10) with the height sensor (29) against the vehicle body is used. Is lowered at a high speed until a predetermined height against the vehicle body is measured, and after reaching the height against the vehicle body, a descending control for lowering the rotary tiller apparatus (10) in a decelerated state is performed. An agricultural tractor having a control device (40) for performing, comprising a speed sensor (39) for measuring the traveling speed of a traveling vehicle body, and the higher the speed measured by the speed sensor (39), the more the lowering control is performed during the lowering control. The height changing means (E) for changing the value of the height relative to the vehicle body for switching from the high speed descending state to the low speed descending state, and the position from the position thus changed to the high side by the height changing means (E). Compared to low speed running even when descending And speed changing means (F) for increasing the descending speed of the rotary tiller (10) during the descending control to a speed set to a value that shortens the time from the start of descending until the rotary tiller (10) touches the ground. Agricultural tractor equipped with.
【請求項2】 前記下降制御でロータリ耕耘装置(1
0)を下降させて前記自動耕深制御に切り換わった際
に、該自動耕深制御における上昇制御を設定時間だけ阻
止する規制手段(G)を備えると共に、前記速度センサ
で計測される速度が速いほど、この規制手段(G)にお
ける設定時間を短くする時間変更手段(H)を備えてい
る請求項1記載の農用トラクタ。
2. A rotary tiller (1) according to the descending control.
0) is lowered to switch to the automatic plowing depth control, the restraint means (G) is provided for blocking the rising control in the automatic plowing depth control for a set time, and the speed measured by the speed sensor is The agricultural tractor according to claim 1, further comprising a time changing means (H) for shortening a set time in the restricting means (G) as the speed increases.
【請求項3】 前記アクチュエータ(11)が油圧シリ
ンダで構成されると共に、前記速度変更手段(F)が、
前記速度センサ(39)で計測される速度が速いほど油
圧シリンダに対する制御弁(V)の作動油の単位時間内
の給排量を増大させる制御動作を行うよう構成されてい
る請求項1記載の農用トラクタ。
3. The actuator (11) is composed of a hydraulic cylinder, and the speed changing means (F) is
The control operation according to claim 1, wherein the control operation is performed such that the higher the speed measured by the speed sensor (39), the larger the supply / discharge amount of the working oil of the control valve (V) to the hydraulic cylinder per unit time. Agricultural tractor.
JP05041596A 1996-03-07 1996-03-07 Agricultural tractor Expired - Lifetime JP3321517B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP05041596A JP3321517B2 (en) 1996-03-07 1996-03-07 Agricultural tractor

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP05041596A JP3321517B2 (en) 1996-03-07 1996-03-07 Agricultural tractor

Publications (2)

Publication Number Publication Date
JPH09238508A true JPH09238508A (en) 1997-09-16
JP3321517B2 JP3321517B2 (en) 2002-09-03

Family

ID=12858240

Family Applications (1)

Application Number Title Priority Date Filing Date
JP05041596A Expired - Lifetime JP3321517B2 (en) 1996-03-07 1996-03-07 Agricultural tractor

Country Status (1)

Country Link
JP (1) JP3321517B2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002010703A (en) * 2000-06-29 2002-01-15 Iseki & Co Ltd Rolling controller of seedling transplanter
CN106982562A (en) * 2017-04-26 2017-07-28 江苏大学 A kind of automatically controlled adjusting means of tractor tilling depth and adjusting method based on driving wheel load

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4728043B2 (en) * 2005-05-19 2011-07-20 ヤンマー株式会社 Tractor depth control mechanism

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002010703A (en) * 2000-06-29 2002-01-15 Iseki & Co Ltd Rolling controller of seedling transplanter
JP4517467B2 (en) * 2000-06-29 2010-08-04 井関農機株式会社 Seedling planting machine
CN106982562A (en) * 2017-04-26 2017-07-28 江苏大学 A kind of automatically controlled adjusting means of tractor tilling depth and adjusting method based on driving wheel load

Also Published As

Publication number Publication date
JP3321517B2 (en) 2002-09-03

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