Patent ID: 7248019
Filing Date: 2007-07-24
Classification: B25C,B25H,H02J

Abstract:
1. A cordless power tool comprising: a plurality of electric double layer capacitors mounted in a tool main body as a power supply of a motor and recharge able by an external power supply; a charging electrode provided in the tool main body; a contact arm; a safety switch that is turned on when the contact arm is pressed; a trigger lever; and a trigger switch that is turned on when the trigger lever is pulled; when the safety switch and the trigger switch are off, the plurality of electrical double layer capacitors are connected in parallel, when the safety switch is turned on, the plurality of electric double layer capacitors are connected in series, and when the safety switch and the trigger switch are turned on, current is supplied from the plurality of electric double layer capacitors connected in series to the motor.