| 摘要 |
<p>In a screw driver for driving a screw by moving a driver bit downward in the driving direction by rotating the driver bit with an air motor, there has been a problem of incomplete tightening of the screw as the main body portion floats due to reaction when the piston reaches the downward motion end. In the invention, an air motor is actuated again when the main body portion is pressed against the screw drive material and operated again, and the screw is tightened additionally. When the main body portion (2) is pressed against the screw drive material and operated again after the piston (22) reached the downward motion end and the air motor is stopped, an auxiliary air supply passage different from the main air supply passage for rotating the air motor is opened and the air motor is actuated again, thus tightening the screw additionally.</p> |
