PROBLEM TO BE SOLVED: To simply and accurately achieve engagement without causing an error in engagement with an upper engaging part of a working unit of a different type even if a plurality of upper connecting parts are provided in a vertical direction.SOLUTION: A connection frame 6 is connected to a tractor body 2 through a three-point link mechanism 5 having a top link 3 and a pair of right and left lower links 4. A first upper connecting part 7A and a second upper connecting part 7B spaced from each other in the vertical direction and a pair of right and left lower connecting parts 8 at one portion or two portions spaced from each other in the vertical direction are formed on the connection frame 6, and two or more kinds of upper engaging parts 10 different in a distance from the upper engaging part 10 the lower engaging part 11 of the working unit 9 and a pair of right and let engaging parts 11 are respectively engaged. Two or more kinds of upper engaging parts 10 of the working unit 9 are made different in shape, and a recessed part Y opened upward is formed on the connection frame 6. A first upper connecting part 7A for a first kind of a working unit 9 is formed on the opening side of the recessed part Y Y, and a second upper connecting part 7B for a second kind of a working unit 9B is formed on the depth side of the recessed part Y.COPYRIGHT: (C)2014,JPO&INPIT【課題】 上連結部が上下方向複数あっても、種類の異なる作業機の上係合部と係合間違いを生じることなく簡単かつ正確に係合できるようにする。【解決手段】 トラクタ車体2にトップリンク3及び左右一対のロワーリンク4を有する3点リンク機構5を介して連結枠6を連結し、この連結枠6に上下に離れた第1上連結部7A及び第2上連結部7Bと1箇所又は上下に離れた2箇所の左右一対の下連結部8とを形成して、上係合部10から下係合部11までの距離の異なる2種類以上の作業機9の上係合部10及び左右一対の下係合部11をそれぞれ係合する。2種類以上の作業機9の上係合部10の形状を異ならせ、連結枠6の上部に上向き開口した凹部Yを形成し、凹部Yの口側に第1種の作業機9A用の第1上連結部7Aを形成し、凹部Yの奥側に第2種の作業機9B用の第2上連結部7Bを形成する。【選択図】図1
