| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for an electrical tool assuring the reach of a workpiece actuated by a drill to a prescribed position in the tool, and surely preventing the workpiece from going beyond the position.SOLUTION: An electrical tool includes a motor arranged for driving a working head to be rotated at a rotational speed, an electric power supply supplying a motor current, and a control element sensing a variable ratio of the current per hour, and generating a control signal for decelerating the rotational speed of the motor accordingly. An electronic control element added to the electrical tool automatically detects whether a working element driven by the working head reaches a prescribed position or not. Moreover, the electronic control element executes a corresponding operation after the reach of the working head to the prescribed position is detected, and surely prevents it from going further beyond the prescribed position. |
