| 摘要 |
A hammer drill (1) includes a shaft (110) with a main clutch gear (120), the shaft (110) being rotatable by a driving force of a driving motor, and having a mode conversion among a hammer mode for hitting a bit (60) as a rotary motion of the shaft (110) is converted into a linear reciprocation, a drill mode for rotating the bit by rotation of the shaft (110), and a hammer drill mode for rotating and hitting the bit (60). A hammer moving gear (160) and a drill moving gear (130) are formed in the same shape. A drill side restoration spring (140) is installed between a drill driving unit (150) engaged with the drill moving gear (130), and the drill moving gear (130). And a hammer side restoration spring (170) is installed between a hammer driving unit (180) engaged with the hammer moving gear (160), and the hammer moving gear (160). With such a configuration, the gears (120, 130, 160) can be easily engaged with each other by restoration forces of the springs (140, 170). |
