Patent ID: 9579776
Date: 2017-02-28
CPC Classifications: B25B,H02P

Claim:
1. An electric power tool comprising: a power supply; a motor including a drive shaft; a trigger switch to adjust an output of the motor; a tool output shaft configured to be driven based on a torque of the drive shaft of the motor; a voltage step-up condition setting operation unit that serves as a human machine interface; a voltage converter capable of performing a voltage step-up operation to raise a voltage supplied from the power supply and supply a raised voltage to the motor, the voltage converter being capable of changing a voltage step-up level in the voltage step-up operation in accordance with the operation of the voltage step-up condition setting operation unit; a driving state detection unit configured to generate a driving state signal corresponding to a driving state of the electric power tool; and a control unit configured to determine whether or not a load torque acting on the tool output shaft is greater than or equal to a prescribed torque in accordance with the driving state signal and stop the driving of the motor when the load torque is the prescribed torque or more, wherein the control unit is configured to perform a starting voltage step-up control, and the voltage converter is configured to, in the starting voltage step-up control, increase the voltage step-up level over time after the operation of the trigger switch.