US Patent 9755490 Power tool

A power tool includes a housing and a brushless motor, the brushless motor having a stator and a rotor inside the housing, the rotor including a rotor core having a plurality of axially extending through holes and a permanent magnet in each of the plurality of through holes. The rotor is provided with at least one positioning structure by which the rotor core can be held in a desired circumferential orientation while the permanent magnets are inserted into the through holes.