PROBLEM TO BE SOLVED: To adjust the height of ridges while easily performing ridging by using a rear cover.SOLUTION: A tilling part 4 includes the elastically deformably rear cover 14 disposed in the rear end of a rotary cover 13 rotatably in the vertical direction for tilling a soil for tilling, and a rear member 21 disposed in the rear of the rear cover 14 in such a way that the position can be changed in the vertical direction. The rear member 21 has a plate 20 for making the rear cover 14 function as a hiller for ridging by pressing the rear cover 14 at a prescribed position from the rear, and a moving tail wheel 26 for supporting the rear of a machine body when the machine body is moved. The moving tail wheel 26 is configured to freely change the posture to a storage posture to be held at a non-grounded position, to a machine body moving posture grounded when the machine body is moved to support the rear of the machine body, or to a ridge height adjusting posture grounded during ridging to adjust the height of ridges.COPYRIGHT: (C)2012,JPO&INPIT【課題】リヤカバーを利用して簡易にうね立てを行うものでありながら、うね高さの調節も可能とする。【解決手段】耕耘部4は、ロータリカバー13の後端部に上下回動自在に設けられて耕耘土を均す弾性変形自在なリヤカバー14と、該リヤカバー14の後方に上下位置変更自在に設けられる後方部材21とを備え、該後方部材21に、リヤカバー14の所定位置を後方から押さえることによってリヤカバー14をうね立て用の培土板として機能させるプレート20と、機体移動時に機体後部を支える移動尾輪26とを設けると共に、該移動尾輪26を、非接地位置に保持される格納姿勢と、機体移動時に接地して機体後部を支える機体移動姿勢と、うね立て時に接地してうね高さを調節するうね高さ調節姿勢とに変姿自在に構成する。【選択図】図19
