PROBLEM TO BE SOLVED: To miniaturize a work case unit by devising a drive side rotary member, a driven side rotary member, a clutch operation member and an arrangement structure of a pushing spring.SOLUTION: A work clutch 8 in a work case unit 4 includes a drive side rotary member 80, a driven side rotary member 81 and a pushing spring 82. A clutch operation member 83 is included which is engaged with an engagement part 81c in an outer circumferential side of the driven side rotary member 81, and can operate the driven side rotary member 81 to the side separated from the drive side rotary member 80 against the pushing spring 82. The pushing spring 82 is equipped in the inside in the radial direction rather than an engagement place between the clutch operation member 83 and the engagement part 81c.SELECTED DRAWING: Figure 4COPYRIGHT: (C)2018,JPO&INPIT【課題】駆動側回転部材と従動側回転部材とクラッチ操作部材と、押し付けバネの配設構造を工夫して、作業ケース部の小型化を図る。【解決手段】作業ケース部４内の作業クラッチ８が、駆動側回転部材８０と、従動側回転部材８１と、押し付けバネ８２を備え、従動側回転部材８１の外周側の係合部８１ｃに係合して、押し付けバネ８２に抗して従動側回転部材８１を駆動側回転部材８０から離れる側へ操作可能なクラッチ操作部材８３を備え、押し付けバネ８２は、クラッチ操作部材８３と係合部８１ｃとの係合箇所よりも半径方向での内方側に装備されている。【選択図】図４
