PROBLEM TO BE SOLVED: To provide a rotation apparatus for an extended leveling plate that surely brings down an extended leveling plate to a working position side or a storage position side when an interlocking arm is rotated in a state in which a first leveling plate is raised.SOLUTION: The rotation apparatus 40 for an extended leveling plate that is mounted on a soil puddling working machine 1 equipped with a shield cover for covering the upper part of a rotatably supported plowing rotor 23, a second leveling plate (left) 29L which is arranged rotatably in the vertical direction behind the shield cover and levels cultivated soil plowed by the plowing rotor 23 and an extended leveling plate (left) 30L rotatably supported around a shaft part 31 extended in the cross direction at an end part in the right and left directions relative to the progress direction of the second leveling plate (left). The apparatus includes: a motor for forward and reverse rotation arranged at the upper part of the shield cover the interlocking arm 53 which is extended in an approximately vertical direction, connected to a spindle 51 receiving power from the motor and rotated, and is turned and a connected body 60 for connecting the tip end part of the interlocking arm to the extended leveling plate (left) 30L. The base end part of the interlocking arm 53 is connected to the spindle 51 in a state in which the rotary central shaft line of the base end part is inclined to the front side in the progress direction.COPYRIGHT: (C)2013,JPO&INPIT【課題】第1整地板が持ち上げられた状態で連動アームの回動時に、延長整地板を作業位置側又は格納位置側へ確実に倒すことができる延長整地板回動装置を提供する。【解決手段】延長整地板回動装置40は、回転自在に支持された耕耘ロータ23の上部を覆うシールドカバーと、この後方に上下方向に回動自在に配設されて耕耘ロータ23により耕耘された耕土を整地する第2整地板左29Lと、この進行方向に対して左右方向の端部に前後方向に延設された軸部31を中心として回動自在に支持された延長整地板左30Lとを備える代かき作業機1に設けられ、シールドカバーの上方に配設された正逆回転用モータと、略垂直方向に延びてモータからの動力を受けて回動する支軸51に連結されて回動する連動アーム53と、この先端部と延長整地板左30Lとを繋ぐ連結体60とを備える。連動アーム53の基端部は、その回動中心軸線が進行方向前側に傾いた状態で支軸51に連結される。【選択図】 図1