WORK MACHINE AND PROTECTIVE COVER

To provide a work machine configured so that powder dust can be suppressed from intruding into a housing and a protective cover that can be detachably attached to the work machine.SOLUTION: A disk grinder 1 comprises: an output shaft 51 which a grindstone P can be attached to and detached from; a gear case 23 having a bearing holding part 231 that holds a ball bearing 23B that pivotally supports the output shaft 51 rotatably; a wheel guard 6 that is mounted on the bearing holding part 231 and covers at least a portion of the grindstone P with the grindstone P mounted on the output shaft 51; and a shielding part 63, positioned between the grindstone P and the ball bearing 23B in a vertical direction, which extends in a radial direction of the output shaft 51 and surrounds a whole area in a circumferential direction of at least a portion of the output shaft 51 in the vertical direction.SELECTED DRAWING: Figure 5 【課題】ハウジング内への粉塵の侵入を抑制可能な作業機及び当該作業機に着脱可能な保護カバーを提供する。【解決手段】ディスクグラインダ１は、砥石Ｐを着脱可能な出力軸５１と、出力軸５１を回転可能に軸支するボールベアリング２３Ｂを保持する軸受保持部２３１を有するギヤケース２３と、軸受保持部２３１に取付けられ砥石Ｐが出力軸５１に取付けられた状態において砥石Ｐの少なくとも一部を覆うホイールガード６と、出力軸５１の径方向に延びるとともに上下方向における出力軸５１の少なくとも一部の周方向全域を取り囲み、上下方向において砥石Ｐとボールベアリング２３Ｂとの間に位置する遮蔽部６３と、を有する。【選択図】図５