PROBLEM TO BE SOLVED: To enable a screw not only to be connected to a drive shaft by fixing the drive shaft temporarily but also to be tightened by appropriate clamping torque without using a specialized tool.SOLUTION: A bush cutter 1 in which a drive shaft 5 rotatably held is rotated integrally with an a rotary blade 6 mounted to the drive shaft 5 includes a rotation control mechanism 40 capable of switching an operational state that the rotation of the drive shaft 5 is controlled and a non-operational state that the rotation of the drive shaft 5 is not controlled. The rotation control mechanism 40 controls the rotation of the drive shaft 5 when it is in the operational state and also releases the control when a rotational torque applied to the drive shaft 5 reaches a prescribed value.COPYRIGHT: (C)2013,JPO&INPIT【課題】駆動軸を一時的に固定して駆動軸にねじを結合可能とするのみでなく、専用工具を使用することなく、ねじを適正な締付トルクで締め付け可能とする。【解決手段】回転自在に保持されている駆動軸5に取り付けられた回転刃6が駆動軸5と一体回転する刈払機1であって、駆動軸5の回転を規制する作動状態と駆動軸5の回転を規制しない非作動状態とに切り替え可能な回転規制機構40を有し、回転規制機構40は、作動状態にあるときに、駆動軸5の回転を規制するとともに、駆動軸5に作用する回転トルクが規定値に達すると規制を解除する。【選択図】図4
