| 摘要 |
A screw driver capable of stably stopping a bit to stabilize fastening depth of a screw. The screw driver includes a rotary portion, a housing, and a clutch mechanism. The rotary portion is rotated by a power source and has a bit engageable with a screw. The rotary portion also has a moving portion holding the bit and movable between a top dead center and a bottom dead center in an axial direction of the rotary portion. The housing rotatably supports the rotary portion. The clutch mechanism includes a first clutch plate unrotatable relative to the housing, and a second clutch plate movable in the axial direction and rotatable integrally with the rotation of the rotary portion. The first and second clutch plates are positioned to be urged by the moving portion and pressed together when the moving portion reaches the bottom dead center. |
