US 11,701,759 B2
Electric power tool
Itsuku Kato, Anjo (JP); and Yasuhito Kawai, Anjo (JP)
Assigned to MAKITA CORPORATION, Anjo (JP)
Filed by MAKITA CORPORATION, Anjo (JP)
Filed on Sep. 21, 2020, as Appl. No. 17/26,390.
Claims priority of application No. 2019-177316 (JP), filed on Sep. 27, 2019.
Prior Publication US 2021/0094158 A1, Apr. 1, 2021
Int. Cl. B25B 21/02 (2006.01); B25B 23/147 (2006.01); B25B 23/14 (2006.01); B25F 5/00 (2006.01)
CPC B25B 21/02 (2013.01) [B25B 23/1475 (2013.01); B25B 23/1405 (2013.01); B25D 2250/221 (2013.01); B25F 5/001 (2013.01)] 14 Claims
OG exemplary drawing
 
1. An electric power tool comprising:
a motor;
an impact mechanism including a hammer and an anvil, the hammer being configured to be rotated by the motor, the anvil being configured to rotate in response to receiving a rotational force of the hammer, the anvil being configured to be attached to a tool bit, the hammer being configured to impact the anvil in a rotation direction of the hammer in response to receipt of a first torque by the anvil, and the first torque being equal to or greater than a preset magnitude;
a drive circuit configured to supply an electric power to the motor to thereby drive the motor; and
a control circuit electrically connected to the drive circuit and configured to execute a motor control process,
the motor control process including:
setting a magnitude of the electric power to a first magnitude;
switching the magnitude of the electric power from the first magnitude to a second magnitude in response to establishment of a preset condition, the second magnitude being smaller than the first magnitude and greater than zero, and the preset condition being based on a magnitude of a load applied to the motor; and
switching the magnitude of the electric power from the second magnitude to a third magnitude in response to (i) switching the magnitude of the electric power to the second magnitude and (ii) establishment of the preset condition, the third magnitude being smaller than the first magnitude and the second magnitude and greater than zero.