| 摘要 |
<P>PROBLEM TO BE SOLVED: To detect switch-off by a simple structure in a power tool system in which a trigger switch and an FET for pulse control are installed between a secondary battery and a motor. <P>SOLUTION: A power tool includes: a motor 1a; a trigger switch 1b which is serially connected to the motor 1a, and can be arbitrarily turned on/off; a battery group 41 for feeding power to the motor 1a; an FET 31 which is a current route formed between the motor 1a and the battery group 41 and which is arranged on the negative electrode side of the battery group 41; a micro computer 35 which controls the FET 31 so as to repeatedly operate on/off; a voltage buffer circuit 33 which inputs a voltage on the negative electrode side of the battery group 41 in the FET 31 and maintains the voltage; and a power supply circuit 32 which feeds the power of the battery group 41 to the micro computer 35 and feeds or shut off the power of the battery group 41 to the micro computer 35 on the basis of the voltage of the voltage buffer circuit 33. <P>COPYRIGHT: (C)2012,JPO&INPIT |
