PROBLEM TO BE SOLVED: To provide a rotary working machine having a detachable right and left swinging part which freely swings a rear cover right and left.SOLUTION: The rotary working machine includes: a plurality of tilling tines that rotate in the traveling direction by the driving force from an engine of a tractor the rotary cover 16 which covers the tilling tines from above the right and left swinging part 60 which is mounted in the almost center of a rear end of the rotary cover 16, and provided with a swinging member capable of swinging in the width direction of a machine a rear cover rotation shaft 61 that is attached to the swinging member at its center, and can be turned in the forward and rearward direction of the machine and the rear cover 17 fixed on the rear cover rotation shaft 61. The right and left swinging part 60 is detachably mounted on the rear cover rotation shaft 61.COPYRIGHT: (C)2012,JPO&INPIT【課題】リヤカバーを左右に揺動自在とする左右揺動部を着脱可能に備えるロータリー作業機を提供する。【解決手段】トラクタのエンジンからの駆動力によって進行方向に回転する複数の耕耘爪と、耕耘爪を上方より覆うロータリーカバー16と、ロータリーカバー16の後端の略中央に取り付けられた、機体の幅方向に揺動可能な揺動部材を備える左右揺動部60と、中央部を揺動部材に取り付け、機体の前後進方向に回動可能なリヤカバー回動軸61と、リヤカバー回動軸61に固設されたリヤカバー17とを備え、左右揺動部60をリヤカバー回動軸61に着脱可能に取り付ける。【選択図】図1