JP3587901B2

JP3587901B2 - Moving agricultural machine

Info

Publication number: JP3587901B2
Application number: JP03933295A
Authority: JP
Inventors: 藤孝明須; 川治中; 智知文越; 藤勝則加
Original assignee: Yanma Agricultural Equipment Co Ltd; Yanmar Co Ltd
Current assignee: Yanma Agricultural Equipment Co Ltd; Yanmar Co Ltd
Priority date: 1995-02-03
Filing date: 1995-02-03
Publication date: 2004-11-10
Anticipated expiration: 2019-11-10
Also published as: JPH08205610A

Description

【０００１】
【産業上の利用分野】
本発明は例えば耕耘作業を行う耕耘ロータリ作業機を牽引するトラクタに関する。
【０００２】
【従来の技術】
従来、例えばトラクタの後側に耕耘ロータリ作業機またはプラウなどを昇降自在に装設し、このロータリ作業機などによって耕耘作業を行うが、耕耘作業時のトラクタ走行速度を速くしてできるだけ早く作業を終了することが望まれていた。
【０００３】
【発明が解決しようとする課題】
前記従来技術は、走行速度を早くすることにより耕耘作業能率を向上させることができるが、圃場枕地で方向転換させて次工程に移動するとき、作業機の上昇及び下降操作、並びに操向ハンドル操作などに加え、走行速度の減速及び増速操作を行う必要がある等の取扱い操作上の問題が生じる。また、圃場枕地で旋回するときに走行速度を自動的に減速させる枕地旋回スイッチを設けることにより、運転操作の簡略化を容易に行えるが、枕地旋回スイッチのオン操作を作業者が忘れる不具合がある。さらに、圃場枕地で旋回するときに走行速度を自動的に減速させても、作業者の能力または圃場条件などに適応した減速動作を容易に得られない等の問題が生じる。
【０００４】
【課題を解決するための手段】
然るに、本発明は、ロータリ作業機を昇降自在に装設させるトラクタにおいて、圃場枕地でロータリ作業機を上昇させて方向転換させるときに走行速度を自動的に低下させる枕地旋回スイッチを設けると共に、ロータリ作業機の耕耘深さを略一定に保つ耕耘深さ制御と、ロータリ作業機の左右傾斜を略一定に保つ水平制御とを、自動的に行わせる全自動スイッチを設け、また昇降シリンダによって昇降させるロータリ作業機の支持高さ（非耕耘作業位置）を検出するセンサを設け、耕耘作業時に圃場枕地に到達してロータリ作業機を非耕耘作業位置に上昇させたとき、全自動スイッチまたは枕地旋回スイッチの一方または両方がオンの状態で、前記センサ入力によりロータリ作業機の非耕耘作業位置が確認されたとき、減速制御によりエンジン回転数下げ動作が行われ、エンジン回転数を速度設定器の旋回速度入力に基づいて低下させて走行速度を減速させると共に、次工程耕耘作業の開始により、昇降スイッチによるロータリ作業機下降操作が確認されたとき、昇降シリンダが作業機下降動作を行い、増速制御によりエンジン回転数上げ動作が行われ、エンジン回転数を元に戻し、次工程での高速耕耘が開始されるもので、高速走行作業における圃場枕地での旋回操作の簡略化並びに取扱い操作性の向上などを容易に図り得るものである。
【０００６】
【実施例】
以下、本発明の実施例を図面に基づいて詳述する。図１は耕耘制御回路図、図２は全体の側面図、図３は同平面図、図４は耕耘ロータリ作業機部の側面図である。図中（１）は走行車であるトラクタであり、エンジン（２）を内設させるボンネット（３）両側に左右の前走行輪（４）（４）を装設させ、前記ボンネット（３）後部に操向ハンドル（５）を設け、該ハンドル（５）後方に運転席（６）を設置させ、運転席（６）両側外方に左右の後走行輪（７）（７）を装設させると共に、運転席（６）前側のステップ（８）に左右ブレーキペダル（９）（９）及びクラッチペダル（１０）を配設させ、作業者が運転席（６）に座乗して走行移動するように構成している。
【０００７】
また、前記走行輪（４）（７）を駆動するミッションケース（１１）にロワリンク（１２）及びトップリンク（１３）を介して耕耘ロータリ作業機（１４）を取付け、該作業機（１４）をトラクタ（１）後側に昇降自在に装設させるもので、走行主変速レバー（１５）と、前記作業機（１４）を手動操作で昇降させるポジションコントロールレバー（１６）と、前記作業機（１４）を非作業上昇位置及び耕耘作業下降位置にワンタッチ動作で昇降させる昇降スイッチ（１７）を、運転席（６）の右側に配置させると共に、走行副変速レバー（１８）と、前記作業機（１４）への出力を変更させるＰＴＯ変速レバー（１９）を、運転席（６）の左側に配置させる。
【０００８】
さらに、図４乃至図７に示す如く、前記作業機（１４）の中央にギアボックス（２０）を配置し、トラクタ（１）のＰＴＯ軸（２１）から動力を伝えると共に、前記ギアボックス（２０）側面より両側方にビーム（２２）を突出し、該ビーム（２２）のそれぞれの中途部に支持プレート（２３）を固設し、該支持プレート（２３）の前端にはロワリンク（１２）を連結させ、支持プレート（２３）後端にはデプスフレーム（２４）の前端を枢支し、該デプスフレーム（２４）後端側に左右尾輪（２５）（２５）を設けている。
【０００９】
前記ビーム（２２）の外側端にチェーンケース（２６）上部とサイドサポート（２７）上部が固設され、該チェーンケース（２６）下部とサイドサポート（２７）下部の間に耕耘爪軸（２８）が横架され、該耕耘爪軸（２８）上にナタ爪よりなる多数のロータリ爪（２９）…が側面視で放射状に植設されると共に、該ロータリ爪（２９）の回転軌跡上方がロータリカバー（３０）によって覆われ、両側はサイドカバー（３１）によって覆われている。そして、該耕耘爪軸（２８）はギアボックス（２０）内のギア、ビーム（２２）内の伝動軸、チェーンケース（２６）内のスプロケット及びチェーンを介して駆動され、ロータリ爪（２９）…が回転されることによって耕耘ができると共に、ハンドル（３２）の回転操作によって耕耘爪軸（２８）軸芯を中心にロータリカバー（３０）を前後に回転させることができるようにしている。
【００１０】
そして、前記ビーム（２２）に固定するプレート（３３）を前方に突設させ、該プレート（３３）前端に支持杆（３４）が横架され、該支持杆（３４）に取付プレート（３５）が固定され、該取付プレート（３５）に切断刃（３６）の上部が固定されている。なお、切断刃（３６）を左右幅方向でロワーリンク（１２）より機外側方に４本装着すると共に、切断刃（３６）の中間部は後方に湾曲させ、前後に傾斜させる切断刃（３６）の直線形下部を前記ロータリ爪（２９）の回転軌跡の前部内に後傾形に臨ませている。つまり、側面視において切断刃（３６）の下部がロータリ爪（２９）の回転軌跡の前部でオーバーラップするように配置させると共に、切断刃（３６）とこれに隣り合うロータリ爪（２９）の左右方向間隔は狭くして残耕ができないようにしている。但し、外側２本の切断刃（３６）（３６）はロータリ爪（２９）と偏心爪（３７）の間に設ける。また、切断刃（３６）の後面とロータリカバー（３０）の間には仕切板（３８）が配設されている。即ち、該仕切板（３８）は切断刃（３６）の背面に固設されており、仕切板（３８）をロータリカバー（３０）に接近させて、藁や雑草等が入り込み絡み付かないようにしている。また、仕切板（３８）は三角形状に構成されて、上部の辺はロータリカバー（３０）の内側の形状に合わせ、前部の辺は切断刃（３６）の後面の形状に合わせて密着して固定できるようにし、後部の辺は円弧状として藁等を下方へ導く形状としている。そして、仕切板（３８）の幅（板厚）は切断刃（３６）の幅より狭くして、藁や雑草等が絡みつかないようにしている。
【００１１】
さらに、ロータリ爪（２９）上側のロータリカバー（３０）後端に第１支点軸（３９）を介して鋼板製第１リヤカバー（４０）を上下方向に揺動自在に連結させ、第１リヤカバー（４０）後端にゴム製第２リヤカバー（４１）前端を固定させ、下方に均し空間（４２）を形成する第２リヤカバー（４１）後端に鋼板製第３リヤカバー（４３）前端を固定させると共に、第１リヤカバー（４０）後端部の第２支点軸（４４）と第３リヤカバー（４３）前端部の第３支点軸（４５）を左右一対のリンク（４６）（４６）によって連結させ、第３支点軸（４５）と略同軸上に第４支点軸（４７）を設け、第４支点軸（４７）に第１吊下ロッド（４８）下端を連結させ、第３リヤカバー（４３）後端部の第５支点軸（４９）に左右一対の第２吊下ロッド（５０）下端を連結させ、第１リヤカバー（４０）の支持体（５１）に第１及び第２吊下ロッド（４８）（５０）上端側を昇降自在に取付け、各吊下ロッド（４８）（５０）と第３リヤカバー（４３）によって側面視三角形を形成させ、また第２及び第３及び第５支点軸（４４）（４５）（４９）を結ぶ線によって側面視三角形を形成させたもので、第２支点軸（４４）または第３支点軸（４５）を中心に第３リヤカバー（４３）を上方移動させ、第２支点軸（４４）及び支持体（５１）の吊下ロッド（４８）（５０）連結部を支点とした前記カバー（４３）及び各ロッド（４８）（５０）の両てこ機構の動作により各ロッド（４８）（５０）の下方突張りによって前方移動が規制される第３リヤカバー（４３）を後上方に移動させ、第３リヤカバー（４３）両側部が平面視で前後移動するフローティング動作を行わせる。また、第５支点軸（４９）と第１リヤカバー（４０）の支持体（５１）間に左右一対のガスダンパ（５２）を連結させたもので、全ストローク略一定のバネ定数が得られかつストロークも大きく形成できるガスダンパ（５２）によって第３リヤカバー（４３）を支持させ、トラクタ（１）が左右に傾いても第３リヤカバー（４３）の左右均等な加圧によって耕耘面を均すことができるように構成している。
【００１２】
また、前記吊下ロッド（４８）（５０）上端側を支持体（５１）…の軸受体（５３）…に遊嵌挿入させ、軸受体（５３）…の上面側に当接するピン（５４）…を前記ロッド（４８）（５０）に植設させ、前記ロッド（４８）（５０）の下方抜出しを防ぎ、第３リヤカバー（４３）の前方移動を制限すると共に、スプリング（５５）（５５）を巻装させた左右一対のロッド（５６）（５６）下端を第１リヤカバー（４０）上面に連結させ、前記ロッド（５６）上端側をロータリカバー（３０）の支持体（５７）に摺動自在に取付け、第１リヤカバー（４０）をスプリング（５５）によって下方に弾圧するように構成している。
【００１３】
また、前記第３リヤカバー（４３）上面にレーキ支持体（５８）を着脱自在に固定させ、該支持体（５８）に固定させるレーキ（５９）を第３リヤカバー（４３）後方に延出させると共に、図６に示す如く、第２吊下ロッド（５０）上端側を取付ける支持体（５１）の軸（６０）に前記ガスダンパ（５２）上端を連結させ、第２吊下ロッド（５０）とガスダンパ（５２）を可及的に接近させて略平行に設けると共に、前記デプスフレーム（２４）後端に支持フレーム（６１）を介して左右一対の尾輪（２５）（２５）を取付け、左右尾輪（２５）（２５）間に前記レーキ（５９）を配設させるもので、枕地方向転換時に畦などにレーキ（５９）が衝突するのを前記尾輪（２５）によって防止すると共に、路上走行または上方に持上げての保守作業などにおいてレーキ（５９）左右外側のバンパとして尾輪（２５）を兼用させるように構成している。
【００１４】
さらに、ロータリ爪（２９）の回転軌跡上端と略同じ高さまたはそれ以上に高い位置に第１支点軸（３９）を取付け、耕耘作業時に第１支点軸（３９）を中心にリヤカバー（４０）（４１）（４３）が上昇することにより、ロータリ爪（２９）の回転軌跡後方でリヤカバー（４０）（４１）（４３）下方に大きな面積の均し空間（４２）が形成され、リヤカバー（４０）（４１）（４３）によって前方に押す土がロータリ爪（２９）の土跳ね上げ部に至るのを防止し、高速走行での耕耘作業によるロータリ爪（２９）の耕耘負荷増加を防止するもので、耕耘作業時、ロータリ爪（２９）が地上に抜出する地点（Ａ）を中心とする半径の円弧線上に、リヤカバー（４０）（４１）（４３）が耕土によって持上げられて配置され、ロータリ爪（２９）の回転軌跡の面積の約５０パーセント以上の大きさの均し空間（４２）をロータリ爪（２９）回転軌跡後側とリヤカバー（４０）（４１）（４３）の間に形成させ、細かい土塊または軽い土塊など小形物がロータリ爪（２９）によってロータリカバー（４０）（４１）下面の高位置に飛散され、大きい土塊または重い土塊または切り株（稲株）など大形物がロータリ爪（２９）によって低い位置に飛散され、ロータリ爪（２９）の飛散による比重分離作用によって小形物が上層となり、また大形物が下層となり、上層の小形物がリヤカバー（４１）（４３）によって均平にされ、後方のレーキ（５９）によって大形物がさらに下方に押下げられる。従って、大形物によって培土内部の通気性及び通水性が良好に保たれると共に、播種または苗移植に適した状態に培土表層部が小形物によって形成される。
【００１５】
さらに、前記耕耘爪軸（２８）を中心に同一円周上に９０度の間隔で４本のロータリ爪（２９）…を取付け、各ロータリ爪（２９）先端側を交互に左右方向に向けて湾曲させ、耕耘爪軸（２８）の直交平面上で４本１列のロータリ爪（２９）…を耕耘爪軸（２８）軸芯線方向に複数列設けるもので、左右方向で対向させるロータリ爪（２９）（２９）の先端軌跡間に間隙を設け、ロータリ爪（２９）の左右側方湾曲幅を先端軌跡間隙の約２倍の大きさとし、左右方向のロータリ爪（２９）（２９）基端間隔が先端軌跡間隙の約５倍の大きさになるようにロータリ爪（２９）を形成している。また、前記ロータリ爪（２９）は土を切取った後に掬取る形状に湾曲させ、ロータリ爪（２９）の先端湾曲部の水平分力により土を横方向に押移動させる力並びにロータリ爪（２９）の弾力変形の横方向の反撥力により掬取り土を耕耘爪軸（２８）軸芯と略平行な横方向に押出し、左右ロータリ爪（２９）（２９）先端軌跡間隙の残耕となる部位の土を破砕させ、残耕が形成されるのを防ぐ構造としたもので、従来のロータリ爪取付け本数の約７０パーセントの本数のロータリ爪（２９）…を取付け、ロータリ爪（２９）の回転速度を従来の回転速度（１分間に約２００〜４００回転）と略同一とし、トラクタ（１）の走行速度を従来の走行速度（１秒間に約０．５メートル）の約２倍とし、従来に比べて耕耘負荷を増大させることなく、作業能率を約２倍にして耕耘作業を行えるように構成している。また、前記ロータリ爪（２９）の土中突入地点に対し側面視で重複する位置で前記切断刃（３６）を土中に突入させ、切断刃（３６）の土中突入部を後方傾斜支持させ、かつ切断刃（３６）の左右両面を幅を有する偏平面で形成し、牽引により切断刃（３６）が土中に進入する下向きの力と、切開される土が復元力によって切断刃（３６）側面に圧接する力が、切断刃（３６）の抜出し抵抗力として発生し、ロータリ爪（２９）の土中突入抵抗の反力と略等しいか若干大きい切断刃（３６）の抜出し抵抗力により、土中突入抵抗の反力によって耕耘ロータリ作業機（１４）全体が上方に持上げられるのを防ぎ、ロータリ爪（２９）が土中突入によって発生する衝撃を緩和させるように構成している。なお、耕耘爪軸（２８）後方側では、リヤカバー（４０）（４１）（４３）の均平力の反力（持上げ力）に対向してロータリ爪（２９）抜出し力の反力が発生し、各反力の均衡によって耕耘姿勢を安定させる。
【００１６】
さらに、図１に示す如く、耕耘深さ制御及び水平制御及び下げクッション制御を自動的に行わせる全自動スイッチ（６２）と、ロータリ作業機（１４）の非耕耘作業位置上昇によってエンジン（２）回転を下げる枕地旋回スイッチ（６３）と、昇降スイッチ（１７）と、エンジン（２）の回転数を増減させる電子ガバナの調速モータ（６４）を作動させるエンジン出力回路（６５）と、ロワーリンク（１２）を介してロータリ作業機（１４）を昇降させる油圧昇降シリンダ（６６）を制御するための電磁油圧昇降バルブ（６７）を作動させる昇降回路（６８）を、マイクロコンピュータで構成する耕耘コントローラ（６９）に接続させるもので、ロータリ作業機（１４）の耕耘深さを略一定に保つ耕耘深さ制御と、ロータリ作業機（１４）の左右傾斜を略水平（一定）に保つ水平制御と、ロータリ作業機（１４）を高速下降させた後に低速下降させて着地衝撃を少なくする下げクッション制御を、全自動スイッチ（６２）のオンにより自動的に行わせる。また、昇降シリンダ（６６）によって昇降させるロータリ作業機（１４）の支持高さ（耕耘作業位置乃至非耕耘作業位置）を検出するポテンショメータ型リフトアームセンサ（７０）を、前記耕耘コントローラ（６９）に接続させるもので、全自動スイッチ（６２）のオン操作または枕地旋回スイッチ（６３）のオン操作の少なくともいずれか一方の操作により、ロータリ作業機（１４）の上昇によってエンジン（２）回転を下げ、かつ下降によってエンジン（２）回転を上げる動作を自動的に行わせるように構成している。なお、前記調速モータ（６４）に代えて調速ソレノイドを電子ガバナに設けてもよいと共に、前記リフトアームセンサ（７０）に代えて昇降検出スイッチを設けてもよい。
【００１７】
上記から明らかなように、走行車であるトラクタ（１）に対地作業機である耕耘ロータリ作業機（１４）を昇降自在に装設させる移動農機において、圃場枕地でロータリ作業機（１４）を上昇させてトラクタ（１）に方向転換させるときに走行速度を自動的に低下させる枕地旋回スイッチ（６３）を設けると共に、農作業自動制御をオンオフする全自動スイッチ（６２）のオン操作により、枕地旋回スイッチ（６３）がオフであってもオンのときと同一動作を行わせる耕耘コントローラ（６９）を設け、枕地旋回スイッチ（６３）のオンによって旋回時に走行速度を自動的に減速させる枕地旋回制御が全自動スイッチ（６２）のオンだけでも行われ、枕地旋回スイッチ（６３）のオン操作を忘れても枕地旋回を適正速度で行えるように構成している。
【００１８】
さらに、圃場枕地での旋回走行速度を作業者が初期設定する可変抵抗器型の速度設定器（７１）を、前記耕耘コントローラ（６９）に接続させ、前記スイッチ（６２）（６３）のオンにより旋回時に低下させるエンジン（２）回転数を速度設定器（７１）によって調節するもので、圃場枕地でロータリ作業機（１４）を上昇させてトラクタ（１）を方向転換させるときに走行速度を自動的に低下させる枕地旋回スイッチ（６３）と、ロータリ作業機（１４）を非作業位置に上昇させて圃場枕地で旋回するときの走行速度を設定する旋回速度変更部材である速度設定器（７１）を設け、圃場枕地における旋回走行速度を作業者の能力または圃場条件などに応じて設定することにより、作業者の能力または圃場条件などに適応した自動減速動作を得られるように構成している。
【００１９】
本実施例は上記の如く構成しており、図８のフローチャートに示す如く、全自動スイッチ（６２）をオン操作すると、ロータリ作業機（１４）の耕耘深さを略一定に保つ耕耘深さ制御動作と、ロータリ作業機（１４）の左右傾斜を略水平（一定）に保つ水平制御動作と、ロータリ作業機（１４）を高速下降させた後に低速下降させて着地衝撃を少なくする下げクッション制御動作が自動的に行われる。また、全自動スイッチ（６２）のオン操作及び枕地旋回スイッチ（６３）のオン操作の少なくともいずれか一方の操作が行われているとき、エンジン（２）最高回転で高速走行（１秒間に約１．０メートル）により高速耕耘が行われるトラクタ（１）が圃場枕地に到達し、昇降スイッチ（１７）によりロータリ作業機（１４）が上昇操作されると、昇降バルブ（６７）制御によって昇降シリンダ（６６）が作業機上昇動作を行い、ロータリ作業機（１４）を非耕耘作業位置に上昇させ、全自動スイッチ（６２）または枕地旋回スイッチ（６３）の一方または両方がオンの状態で、リフトアームセンサ（７０）入力によりロータリ作業機（１４）の非耕耘作業位置が確認されることにより、調速モータ（６４）減速制御によりエンジン（２）回転数下げ動作が行われ、エンジン（２）回転数を速度設定器（７１）の旋回速度入力に基づいて低下させ、作業者の能力または圃場条件に適した走行速度に減速させる。そして、操向ハンドル（５）操作によってトラクタ（１）を約１８０旋回させ、次工程作業位置に移動させる。
【００２０】
また、次工程耕耘作業の開始により、昇降スイッチ（１７）によるロータリ作業機（１４）下降操作が確認されると、昇降バルブ（６７）制御によって昇降シリンダ（６６）が作業機下降動作を行い、ロータリ作業機（１４）を耕耘作業位置に下降させると共に、調速モータ（６４）増速制御によりエンジン（２）回転数上げ動作が行われ、エンジン（２）回転数を元の最高回転に戻し、次工程での高速耕耘が開始される。
【００２１】
さらに、図９は他の実施例を示すもので、耕耘深さ制御及び水平制御及び下げクッション制御及び枕地旋回制御を自動的に行わせる全自動スイッチ（６２）と、ロータリ作業機（１４）の耕耘深さを略一定に保つ耕耘深さ制御を停止させる耕深制御オフスイッチ（７２）と、ロータリ作業機（１４）の左右傾斜を略水平（一定）に保つ水平制御を停止させる水平制御オフスイッチ（７３）と、ロータリ作業機（１４）を高速下降させた後に低速下降させて着地衝撃を少なくする下げクッション制御を停止させるクッション制御オフスイッチ（７４）と、枕地旋回時にエンジン（２）回転を下げて走行速度を減速させる枕地旋回制御を停止させる枕地旋回制御オフスイッチ（７５）を、耕耘コントローラ（６９）に接続させる。そして、図１０のフローチャートに示す如く、ロータリ作業機（１４）の耕耘深さを略一定に保つ耕耘深さ自動制御を耕深制御オフスイッチ（７２）のオンにより中止させ、またロータリ作業機（１４）の左右傾斜を略水平（一定）に保つ自動水平制御を水平制御オフスイッチ（７３）のオンにより中止させ、またロータリ作業機（１４）を高速下降させた後に低速下降させて着地衝撃を少なくする下げクッション自動制御をクッション制御オフスイッチ（７４）のオンにより中止させ、また枕地旋回時にエンジン（２）回転を下げて走行速度を減速させる枕地旋回自動制御を枕地旋回制御オフスイッチ（７５）のオンにより中止させるもので、全自動スイッチ（６２）のオンにより全ての自動制御を作動させると共に、各オフスイッチ（７２）〜（７５）のオン操作により、作業者の選択によって任意の自動制御を中止させ、自動制御のオン操作忘れをなくすように構成することも行える。
【００２２】
【発明の効果】
以上実施例から明らかなように本発明は、ロータリ作業機（１４）を昇降自在に装設させるトラクタにおいて、圃場枕地でロータリ作業機（１４）を上昇させて方向転換させるときに走行速度を自動的に低下させる枕地旋回スイッチ（６３）を設けると共に、ロータリ作業機（１４）の耕耘深さを略一定に保つ耕耘深さ制御と、ロータリ作業機（１４）の左右傾斜を略一定に保つ水平制御とを、自動的に行わせる全自動スイッチ（６２）を設け、また昇降シリンダ（６６）によって昇降させるロータリ作業機（１４）の支持高さ（非耕耘作業位置）を検出するセンサ（７０）を設け、耕耘作業時に圃場枕地に到達してロータリ作業機（１４）を非耕耘作業位置に上昇させたとき、全自動スイッチ（６２）または枕地旋回スイッチ（６３）の一方または両方がオンの状態で、前記センサ（７０）入力によりロータリ作業機（１４）の非耕耘作業位置が確認されたとき、減速制御によりエンジン（２）回転数下げ動作が行われ、エンジン（２）回転数を速度設定器（７１）の旋回速度入力に基づいて低下させて走行速度を減速させると共に、次工程耕耘作業の開始により、昇降スイッチ（１７）によるロータリ作業機（１４）下降操作が確認されたとき、昇降シリンダ（６６）が作業機（１４）下降動作を行い、増速制御によりエンジン（２）回転数上げ動作が行われ、エンジン（２）回転数を元に戻し、次工程での高速耕耘が開始されるもので、高速走行作業における圃場枕地での旋回操作の簡略化並びに取扱い操作性の向上などを容易に図ることができるものである。
【図面の簡単な説明】
【図１】耕耘制御回路図。
【図２】全体の側面図。
【図３】同平面図。
【図４】耕耘ロータリ作業機の側面図。
【図５】ロータリ爪部の側面図。
【図６】リヤカバーの平面図。
【図７】ロータリ爪部の背面図。
【図８】耕耘制御フローチャート。
【図９】図１の変形例を示す耕耘制御回路図。
【図１０】前図のフローチャート。
【符号の説明】
（１）トラクタ（走行車）
（１４）耕耘ロータリ作業機（対地作業機）
（６２）全自動スイッチ
（６３）枕地旋回スイッチ
（６９）コントローラ
（７１）速度設定器（旋回速度変更部材）[0001]
[Industrial applications]
The present invention relates to a tractor towing the plow rotary working machine performing, for example, tilling.
[0002]
[Prior art]
Conventionally, for example, a tilling rotary work machine or a plow is installed on the rear side of the tractor so as to be able to move up and down freely, and cultivation work is performed by this rotary work machine, etc. It was desired to end.
[0003]
[Problems to be solved by the invention]
The above prior art can improve the tillage work efficiency by increasing the traveling speed, but when moving to the next step after turning in the field headland, raising and lowering the working machine, and the steering handle In addition to the operation, there is a problem in handling operation such as the necessity of decelerating and increasing the running speed. Also, by providing a headland turning switch that automatically reduces the traveling speed when turning on the field headland, the driving operation can be simplified easily, but the operator forgets to turn on the headland turning switch. There is a defect. Further, even if the traveling speed is automatically reduced when turning on the field headland, there arises a problem that a deceleration operation adapted to the ability of the worker or the field conditions cannot be easily obtained.
[0004]
[Means for Solving the Problems]
Therefore, the present invention provides a tractor in which a rotary work machine is mounted so as to be able to move up and down freely, and a headland turning switch that automatically lowers a traveling speed when the rotary work machine is raised and turned in a field headland. A fully automatic switch is provided to automatically perform the tillage depth control that keeps the tillage depth of the rotary work machine substantially constant, and the horizontal control that keeps the left and right inclination of the rotary work machine approximately constant, and the lifting cylinder support height of the rotary working machine for lifting is a sensor for detecting the (non-tilling position) provided, when raising the rotary working machine reaches the field pillow areas during tilling in the non-tilling position, fully automatic switch or in one or both turned on the headland turn switch, when the non-tilling working position of the rotary working machine is confirmed by the sensor input, engine by deceleration control A rotation speed reduction operation is performed, the engine speed is reduced based on the turning speed input of the speed setting device to reduce the running speed, and the start of the next process tilling operation confirms the lowering operation of the rotary work machine by the lifting switch. Then, the lifting cylinder performs the lowering operation of the work machine, the engine speed is increased by the speed increase control, the engine speed is returned, and the high-speed tilling in the next process is started. This makes it easy to simplify the turning operation at the headland on the field and to improve the handling operability during the operation.
[0006]
【Example】
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 is a tillage control circuit diagram, FIG. 2 is a side view of the entirety, FIG. 3 is a plan view of the same, and FIG. 4 is a side view of a tillage rotary working machine. In the figure, reference numeral (1) denotes a tractor which is a traveling vehicle. A left and right front traveling wheels (4) and (4) are provided on both sides of a bonnet (3) in which an engine (2) is provided. A steering wheel (5), a driver's seat (6) is installed behind the handle (5), and left and right rear running wheels (7) (7) are installed outside both sides of the driver's seat (6). At the same time, the left and right brake pedals (9) and (9) and the clutch pedal (10) are arranged at the step (8) in front of the driver's seat (6), and the operator travels while sitting on the driver's seat (6). It is configured as follows.
[0007]
A tillage rotary work machine (14) is attached to a transmission case (11) for driving the running wheels (4) and (7) via a lower link (12) and a top link (13), and the work machine (14) is mounted. The tractor (1) is mounted on the rear side so as to be able to ascend and descend freely, and includes a traveling main speed change lever (15), a position control lever (16) for elevating and lowering the work implement (14) by manual operation, and ) Is arranged on the right side of the driver's seat (6) with a one-touch operation of raising and lowering the non-working raising position and the tilling work lowering position, and a traveling auxiliary transmission lever (18) and the work machine (14). The PTO speed change lever (19) for changing the output to the driver seat (6) is arranged on the left side of the driver's seat (6).
[0008]
Further, as shown in FIGS. 4 to 7, a gearbox (20) is arranged at the center of the work machine (14) to transmit power from the PTO shaft (21) of the tractor (1) and to transmit the power to the gearbox (20). ) Beams (22) protrude from both sides from the side surface, and support plates (23) are fixedly provided in the middle of each of the beams (22), and lower links (12) are connected to the front ends of the support plates (23). The front end of the depth frame (24) is pivotally supported at the rear end of the support plate (23), and right and left tail wheels (25) and (25) are provided at the rear end side of the depth frame (24).
[0009]
An upper part of the chain case (26) and an upper part of the side support (27) are fixed to the outer end of the beam (22), and a tilling claw shaft (28) is disposed between the lower part of the chain case (26) and the lower part of the side support (27). A large number of rotary claws (29)... Composed of nata claws are radially implanted on the tilling claw shaft (28) in a side view, and a rotary cover (above the rotation trajectory of the rotary claw (29)). 30), and both sides are covered by side covers (31). The cultivating claw shaft (28) is driven via a gear in the gear box (20), a transmission shaft in the beam (22), a sprocket and a chain in the chain case (26), and a rotary claw (29) ... The rotary cover (30) can be rotated back and forth around the axis of the tilling claw shaft (28) by rotating the handle (32) by rotating the handle (32).
[0010]
Then, a plate (33) fixed to the beam (22) is projected forward, and a support rod (34) is laid on the front end of the plate (33), and a mounting plate (35) is mounted on the support rod (34). Is fixed, and the upper portion of the cutting blade (36) is fixed to the mounting plate (35). In addition, four cutting blades (36) are attached to the outer side of the lower link (12) in the left-right width direction, and the middle part of the cutting blade (36) is curved backward and inclined forward and backward. The lower part of the linear shape of ()) faces backward in the front part of the rotation locus of the rotary claw (29). That is, in a side view, the lower part of the cutting blade (36) is arranged so as to overlap the front part of the rotation trajectory of the rotary claw (29), and the cutting blade (36) and the rotary claw (29) adjacent thereto are arranged. The interval between the left and right directions is narrow so that residual cultivation cannot be performed. However, the two outer cutting blades (36) (36) are provided between the rotary claw (29) and the eccentric claw (37). A partition plate (38) is provided between the rear surface of the cutting blade (36) and the rotary cover (30). That is, the partition plate (38) is fixed to the back surface of the cutting blade (36), and the partition plate (38) is brought close to the rotary cover (30) so that straw, weeds and the like do not enter and become entangled. ing. Further, the partition plate (38) is formed in a triangular shape, and the upper side is closely fitted to the shape inside the rotary cover (30), and the front side is closely fitted to the shape of the rear surface of the cutting blade (36). The rear side is shaped like an arc to guide straw or the like downward. The width (thickness) of the partition plate (38) is made smaller than the width of the cutting blade (36) so that straw, weeds, and the like are not entangled.
[0011]
Further, the first rear cover (40) made of a steel plate is connected to the rear end of the rotary cover (30) on the upper side of the rotary pawl (29) via a first fulcrum shaft (39) so as to be vertically swingable. 40) The front end of the second rubber rear cover (41) is fixed to the rear end, and the front end of the third steel plate rear cover (43) is fixed to the rear end of the second rear cover (41) forming the leveling space (42) downward. At the same time, the second fulcrum shaft (44) at the rear end of the first rear cover (40) and the third fulcrum shaft (45) at the front end of the third rear cover (43) are connected by a pair of left and right links (46) (46). A fourth fulcrum shaft (47) is provided substantially coaxially with the third fulcrum shaft (45), the lower end of the first suspension rod (48) is connected to the fourth fulcrum shaft (47), and the third rear cover (43) A pair of left and right second suspension locks is attached to the fifth fulcrum shaft (49) at the rear end. (50) The lower ends are connected, and the upper ends of the first and second suspension rods (48) and (50) are attached to the support (51) of the first rear cover (40) so as to be able to move up and down. (50) and a third rear cover (43) to form a triangle in side view, and a line connecting the second, third and fifth fulcrum axes (44), (45) and (49) to form a triangle in side view. Then, the third rear cover (43) is moved upward about the second fulcrum shaft (44) or the third fulcrum shaft (45), and the suspension rod (48) of the second fulcrum shaft (44) and the support (51) is moved. (50) The forward movement is regulated by the downward projection of each rod (48) (50) by the operation of the leverage mechanism of the cover (43) and each rod (48) (50) with the connecting portion as a fulcrum. The third rear cover (43) is moved rearward and upward to Yakaba (43) sides is to perform a floating action of moving back and forth in a plan view. Further, a pair of left and right gas dampers (52) is connected between the fifth fulcrum shaft (49) and the support (51) of the first rear cover (40), so that a substantially constant spring constant can be obtained over the entire stroke and the stroke can be reduced. The third rear cover (43) is supported by the gas damper (52) which can be formed large, and even if the tractor (1) is inclined left and right, the tilling surface can be leveled by pressing the third rear cover (43) right and left equally. It is configured as follows.
[0012]
Also, the upper end of the suspension rod (48) (50) is loosely inserted into the bearing (53) of the support (51) so that the pin (54) comes into contact with the upper surface of the bearing (53). . Are implanted in the rods (48) and (50) to prevent the rods (48) and (50) from being pulled out downward, restrict the forward movement of the third rear cover (43), and use the springs (55) and (55). The lower ends of a pair of right and left rods (56) and (56) around which are wound are connected to the upper surface of the first rear cover (40), and the upper end of the rod (56) slides on the support (57) of the rotary cover (30). The first rear cover (40) is freely mounted, and is configured to be elastically pressed downward by a spring (55).
[0013]
A rake support (58) is detachably fixed to the upper surface of the third rear cover (43), and a rake (59) fixed to the support (58) is extended rearward of the third rear cover (43). As shown in FIG. 6, the upper end of the gas damper (52) is connected to the shaft (60) of the support (51) to which the upper end side of the second suspension rod (50) is attached, and the second suspension rod (50) and the gas damper are connected. A pair of tail wheels (25) and (25) are attached to the rear end of the depth frame (24) via a support frame (61), and a pair of left and right tail wheels (25) and (25) are attached. The rake (59) is disposed between the wheels (25) and (25). The tail wheel (25) prevents the rake (59) from colliding with a ridge or the like at the time of headland turning, and also on the road. Maintenance while traveling or lifting up It is configured to also serve the tail wheel (25) works in such as a bumper of the rake (59) left and right outer.
[0014]
Further, the first fulcrum shaft (39) is attached at a position substantially equal to or higher than the upper end of the rotation trajectory of the rotary claw (29), and the rear cover (40) around the first fulcrum shaft (39) during tilling work. As the (41) and (43) rise, a leveling space (42) having a large area is formed below the rear covers (40), (41) and (43) behind the rotation locus of the rotary pawl (29), and the rear cover (40) is formed. (41) (41) and (43) which prevent the soil pushed forward from reaching the soil jumping portion of the rotary claw (29), and prevent the increase in the tilling load of the rotary claw (29) due to the tilling work at a high speed. At the time of tilling work, the rear covers (40), (41), and (43) are lifted and arranged by cultivated soil on an arc line having a radius centered on the point (A) at which the rotary claw (29) is pulled out to the ground. Rotary claw (2 ), A leveling space (42) having a size of about 50% or more of the area of the rotation locus is formed between the rotary claw (29) rear side of the rotation locus and the rear covers (40), (41), (43) to form a fine earth mass. Alternatively, a small object such as a light soil mass is scattered to a high position on the lower surface of the rotary cover (40) (41) by the rotary nail (29), and a large object such as a large earth mass or a heavy earth mass or a stump (rice plant) is rotated. The small object becomes the upper layer, the large object becomes the lower layer by the specific gravity separation action by the scattering of the rotary claw (29), and the small object of the upper layer is leveled by the rear covers (41) and (43). The large object is pushed down further by the rear rake (59). Accordingly, the large-sized material maintains good air permeability and water permeability inside the cultivated soil, and the cultivated soil surface layer is formed by the small-sized material in a state suitable for sowing or seedling transplantation.
[0015]
Further, four rotary claws (29) are mounted on the same circumference around the cultivating claw shaft (28) at 90-degree intervals, and the tips of the rotary claws (29) are alternately turned in the left-right direction. A plurality of rotary nails (29) are provided in a row in the direction of the axis of the cultivating claw shaft (28) on a plane orthogonal to the cultivating claw shaft (28). 29) A gap is provided between the tip trajectories of (29), the width of the left and right lateral curvature of the rotary claw (29) is about twice as large as the gap of the tip trajectory, and the base end of the left and right rotary claw (29) (29) The rotary pawl (29) is formed so that the interval is about five times as large as the tip trajectory gap. Further, the rotary claw (29) is bent into a shape of scooping after cutting off the soil, and a force for pushing and moving the soil in the horizontal direction by a horizontal component force of a tip curved portion of the rotary claw (29) and the rotary claw (29). ), The scooped soil is extruded in the lateral direction substantially parallel to the axis of the tilling claw shaft (28) by the repulsive force of the elastic deformation in the lateral direction, and the left and right rotary claws (29) and (29) are portions of the tip trajectory gap which are left behind. This is a structure that crushes the soil and prevents the formation of residual tillage. The number of rotary pawls (29) is about 70% of the number of conventional rotary pawls, and the rotary pawl (29) is rotated. The speed is almost the same as the conventional rotation speed (about 200 to 400 rotations per minute), and the traveling speed of the tractor (1) is about twice the conventional traveling speed (about 0.5 meters per second). Without increasing the tillage load compared to It is configured to allow the tilling by approximately double the efficiency. Further, the cutting blade (36) is made to penetrate into the soil at a position overlapping with the rotary claw (29) in the soil when viewed from the side, and the submerged portion of the cutting blade (36) is inclined backward and supported. The left and right sides of the cutting blade (36) are formed as uneven planes having a width, and the downward force of the cutting blade (36) entering the soil by traction and the cut soil are restored by the restoring force. ) The force of pressing against the side surface is generated as the pull-out resistance of the cutting blade (36), and the pull-out resistance of the cutting blade (36) is substantially equal to or slightly larger than the reaction force of the rotary claw (29) into the soil. The rotary cultivator (14) is prevented from being lifted upward by the reaction force of the soil rush resistance, and the rotary claw (29) is configured to reduce the shock generated by the soil rush. In addition, on the rear side of the cultivating claw shaft (28), a reaction force of the rotary claw (29) extraction force is generated in opposition to the reaction force (lifting force) of the leveling force of the rear covers (40), (41), and (43). And stabilize the tilling posture by balancing each reaction force.
[0016]
Further, as shown in FIG. 1, the fully automatic switch (62) for automatically performing the tillage depth control, the horizontal control, and the lowering cushion control, and the non-tiling work position of the rotary work machine (14) increase the engine (2). A headland turning switch (63) for lowering the rotation, an elevating switch (17), an engine output circuit (65) for operating a speed control motor (64) of an electronic governor for increasing or decreasing the rotation speed of the engine (2), and a lower A tilling circuit in which a lifting / lowering circuit (68) for operating an electromagnetic hydraulic lifting / lowering valve (67) for controlling a hydraulic lifting / lowering cylinder (66) for lifting / lowering a rotary work machine (14) via a link (12) is constituted by a microcomputer. The cultivation depth control for keeping the cultivation depth of the rotary work machine (14) substantially constant and the cultivation depth control of the rotary work machine (14) connected to the controller (69). A fully automatic switch (62) automatically turns on a horizontal control for keeping the right inclination substantially horizontal (constant) and a lower cushion control for lowering the rotary work machine (14) at a high speed and then at a low speed to reduce landing impact. To be performed. Further, a potentiometer type lift arm sensor (70) for detecting a support height (tiling work position or non-tiling work position) of the rotary work machine (14) to be moved up and down by a lifting cylinder (66) is provided to the tillage controller (69). The rotation of the rotary work machine (14) decreases the rotation of the engine (2) by at least one of the operation of turning on the fully automatic switch (62) and the operation of turning on the headland turning switch (63). In addition, an operation of increasing the rotation of the engine (2) by lowering is automatically performed. In addition, a speed control solenoid may be provided in the electronic governor instead of the speed control motor (64), and a lift detection switch may be provided in place of the lift arm sensor (70).
[0017]
As is apparent from the above description, in a mobile farm machine in which a cultivating rotary work machine (14) as a ground work machine is mounted on a tractor (1) as a traveling vehicle so as to be able to move up and down, the rotary work machine (14) is mounted on a headland in a field. A headland turning switch (63) for automatically lowering the running speed when the tractor (1) is turned up to change the direction is provided, and the pillow is turned on and off by a fully automatic switch (62) for turning on and off automatic agricultural work control. A tilling controller (69) for performing the same operation as when the ground turning switch (63) is turned on even when the ground turning switch (63) is turned on, and a pillow for automatically reducing the traveling speed during turning by turning on the headland turning switch (63). The ground turning control is performed only by turning on the fully automatic switch (62), and the headland turning can be performed at an appropriate speed even if the turning on of the headland turning switch (63) is forgotten. There.
[0018]
Further, a variable resistor type speed setting device (71) for initial setting of a turning traveling speed in the field headland by an operator is connected to the tillage controller (69), and the switches (62) and (63) are turned on. The rotation speed of the engine (2), which is reduced during turning, is adjusted by the speed setting device (71). The traveling speed is increased when the rotary work machine (14) is raised on the field headland to change the direction of the tractor (1). Turning switch (63) for automatically lowering the speed, and a speed setting member which is a turning speed changing member for setting the running speed when turning the rotary work machine (14) to the non-working position and turning on the field headland. A device (71) is provided to set the turning traveling speed in the field headland according to the capability of the operator or the field conditions, etc., thereby performing the automatic deceleration operation adapted to the capability of the operator or the field conditions. It is configured to be.
[0019]
This embodiment is configured as described above, and as shown in the flowchart of FIG. 8, when the fully automatic switch (62) is turned on, the tilling depth control for keeping the tilling depth of the rotary work machine (14) substantially constant. Operation, horizontal control operation for keeping the horizontal inclination of the rotary work machine (14) substantially horizontal (constant), and lowering cushion control operation for lowering the rotary work machine (14) at a high speed and then at a low speed to reduce landing impact. Is done automatically. In addition, when at least one of the operation of turning on the fully automatic switch (62) and the operation of turning on the headland turning switch (63) is performed, the engine (2) runs at high speed at high speed (about one second). (1.0 m), the tractor (1) for high-speed tilling reaches the field headland, and when the rotary work machine (14) is raised by the lifting switch (17), it is raised and lowered by the control of the lifting valve (67). The cylinder (66) performs the work machine raising operation, raises the rotary work machine (14) to the non-tilling work position, and turns one or both of the fully automatic switch (62) and the headland turning switch (63) on. The non-tiling work position of the rotary work machine (14) is confirmed by the input of the lift arm sensor (70), and the speed control motor (64) is decelerated to control the engine (2) times. Number lowering operation is performed, the engine (2) rotational speed of the speed setting unit (71) is lowered on the basis of the turning speed input, to decelerate the running speed suitable for the operator's ability or field conditions. Then, by operating the steering handle (5), the tractor (1) is turned about 180 times and moved to the next process work position.
[0020]
When the lowering operation of the rotary work machine (14) by the elevating switch (17) is confirmed by the start of the next process tilling operation, the elevating cylinder (66) performs the lowering operation of the working machine by controlling the elevating valve (67). The rotary work machine (14) is lowered to the tilling work position, and the speed of the engine (2) is increased by the speed control motor (64), so that the engine (2) speed is returned to the original maximum speed. Then, high-speed tillage in the next process is started.
[0021]
FIG. 9 shows another embodiment, in which a fully automatic switch (62) for automatically performing tillage depth control, horizontal control, lowering cushion control, and headland turning control, and a rotary work machine (14). Depth control off switch (72) for stopping the tilling depth control that keeps the tilling depth of the rotary machine approximately constant, and horizontal control for stopping the horizontal control that keeps the horizontal inclination of the rotary work machine (14) substantially horizontal (constant) An off switch (73), a cushion control off switch (74) for lowering the rotary work machine (14) at a high speed and then lowering the speed at a low speed to stop a lowering cushion control for reducing a landing impact; ) The headland turning control off switch (75) for stopping the headland turning control for reducing the rotation speed to reduce the traveling speed is connected to the tillage controller (69). Then, as shown in the flowchart of FIG. 10, the tillage depth automatic control for keeping the tillage depth of the rotary work machine (14) substantially constant is stopped by turning on a tillage depth control off switch (72). 14) The automatic horizontal control for keeping the horizontal inclination substantially horizontal (constant) is stopped by turning on the horizontal control off switch (73), and the rotary work machine (14) is lowered at high speed and then lowered at low speed to reduce the landing impact. The automatic lowering cushion control is stopped by turning on the cushion control off switch (74), and the automatic headland turning control for lowering the engine (2) rotation to reduce the traveling speed during headland turning is performed by the headland turning control off switch. When the fully automatic switch (62) is turned on, all the automatic controls are activated, and each of the off switches (7) is turned off. ) By on-operation to (75), to stop any automatic control by the selection of the operator, also performed be configured to eliminate the ON operation forgetting automatic control.
[0022]
【The invention's effect】
As is apparent from the above embodiments, the present invention relates to a tractor in which the rotary working machine (14) is mounted so as to be able to move up and down freely when the rotary working machine (14) is lifted and turned in a headland on a field to reduce the traveling speed. A headland swivel switch (63) for automatically lowering is provided, the tillage depth control for keeping the tillage depth of the rotary work machine (14) substantially constant, and the left and right inclination of the rotary work machine (14) substantially constant. A sensor (a non-tiling work position) for detecting a supporting height (non-tiling work position) of the rotary work machine (14) which is provided with a fully automatic switch (62) for automatically performing horizontal control to be maintained and which is raised and lowered by a lifting cylinder (66). 70) is provided, when raised to reach the field pillow areas during tilling rotary working machine (14) in the non-tilling working position, the full automatic switch (62) or headland turn switch (63) Single Or both is on, the sensor (70) when the non-tilling working position of the rotary working machine (14) is confirmed by an input, the engine (2) rotational speed lowering operation is performed by the deceleration control, the engine (2 ) The running speed is reduced by lowering the rotation speed based on the turning speed input of the speed setting device (71), and the lowering operation of the rotary work machine (14) by the elevating switch (17) is started by starting the next step tilling work. When it is confirmed, the lifting / lowering cylinder (66) performs the lowering operation of the work implement (14), the engine (2) rotation speed increasing operation is performed by speed-up control, and the engine (2) rotation speed is returned to the original, and the next process The high-speed tilling is started in the field, and it is possible to easily simplify the turning operation on the headland in the field in the high-speed running operation, improve the handling operability, and the like.
[Brief description of the drawings]
FIG. 1 is a circuit diagram of a tillage control circuit.
FIG. 2 is an overall side view.
FIG. 3 is a plan view of the same.
FIG. 4 is a side view of the tillage rotary working machine.
FIG. 5 is a side view of a rotary claw portion.
FIG. 6 is a plan view of a rear cover.
FIG. 7 is a rear view of the rotary claw portion.
FIG. 8 is a flowchart of a tillage control.
FIG. 9 is a tillage control circuit diagram showing a modification of FIG. 1;
FIG. 10 is a flowchart of the previous figure.
[Explanation of symbols]
(1) Tractor (traveling vehicle)
(14) Tilling rotary work machine (ground work machine)
(62) Fully automatic switch (63) Headland turning switch (69) Controller (71) Speed setting device (turning speed changing member)

Claims

A headland swivel switch (63) for automatically lowering a traveling speed when the rotary work machine (14) is raised and turned in a field headland in a tractor in which the rotary work machine (14) is mounted so as to be movable up and down. And automatically performs the tillage depth control for keeping the tillage depth of the rotary work machine (14) substantially constant and the horizontal control for keeping the left and right inclination of the rotary work machine (14) substantially constant. provided an automatic switch (62), also supporting height of the rotary working machine raising and lowering the lifting cylinder (66) (14) a sensor for detecting the (non-tilling position) (70) is provided, in the field pillow areas during tilling when raised rotary working machine (14) in the non-tilling working position reached, in either or both the oN state of the full automatic switch (62) or headland turn switch (63), said sensor 70) When the non-tilling working position of the rotary working machine (14) is confirmed by an input, the engine (2) rotational speed lowering operation is performed by the deceleration control, the engine (2) speed setter the rotational speed of (71) The traveling speed is reduced by lowering based on the turning speed input, and when the lowering operation of the rotary work machine (14) by the elevating switch (17) is confirmed by the start of the next process tillage operation, the elevating cylinder (66) is moved. The work machine (14) performs the lowering operation, the engine (2) rotation speed increasing operation is performed by the speed increase control, the engine (2) rotation speed is returned to the original, and the high-speed tilling in the next process is started. And a tractor.