| 摘要 |
<P>PROBLEM TO BE SOLVED: To simply carry out self-diagnosis of tightening torque without using an expensive means such as a torque sensor, in a tightening tool having a clutch interrupting torque transmission. <P>SOLUTION: The tightening tool 10 comprises a motor M; a main shaft 20 engaged with screws; and the clutch 14 interposed between the motor M and the main shaft 20, transmitting torque from the motor M to the main shaft 20 when a load applied on the main shaft 20 is less than a predetermined value, and interrupting torque transmission from the motor M to the main shaft 20 when the load applied on the main shaft 20 becomes not less than the predetermined value. The tightening tool 10 is equipped with a control unit 60 for controlling the motor M. The controlling unit 60 detects a current passing through the motor M, and determines whether the tightening torque of the screws is normal or not from a motor current value when the torque transmission from the motor M to the main shaft 20 is interrupted. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
