Electric power tool

摘要

An electric power tool includes a motor with a rotor having a permanent magnet; a control unit that sets a control amount of the motor in accordance with operation of an operation portion and that drive-controls the motor based on the control amount; and a number-of-rotations detection unit that detects the number of rotations of the motor. During driving of the motor, when the number of rotations detected by the number-of-rotations detection unit has reached an upper limit number of rotations set in advance, the control unit shifts drive control of the motor to rotation control, in which the control amount is made to be increased or decreased so that the number of rotations of the motor becomes a predetermined target number of rotations.

主权项

1. An electric power tool comprising:
a motor comprising a rotor, the rotor comprising a permanent magnet; a control unit that is configured to set a control amount of the motor in accordance with operation of an operation portion and to drive-control the motor based on the control amount; and a number-of-rotations detection unit that is configured to detect the number of rotations of the motor, wherein the control unit is configure to shift drive control of the motor to rotation control, in which the control amount is made to be increased or decreased so that the number of rotations of the motor becomes a predetermined target number of rotations during driving of the motor, when at least one predetermined execution condition is satisfied and the number of rotations detected by the number-of-rotations detection unit has reached an upper limit number of rotations set in advance, the at least one execution condition being a condition that there is a possibility that the number of rotations may exceed the upper limit number of rotations during no-load operation of the motor due to a decrease in magnetic force of the rotor caused by a rise in temperature of the rotor.