Power tool having an electronically commutated motor and double insulation

Abstract

A power tool has a housing a housing having an electronically commutated motor disposed therein. The motor has a rotor and a stator. The rotor has permanent magnets. The stator has a lamination stack and windings wound therein. Features are provided to provide double insulation.

1 . A method of making a power tool, the power tool including a housing having an electronically commutated motor disposed therein, the motor having a rotor and a stator, the rotor having permanent magnets, the stator having a lamination stack and windings wound therein, the rotor having a shaft, a sense magnet tray affixed to the shaft of the rotor in proximity to a sensor disposed in the housing, the sensor axially spaced from the sense magnet tray, the method comprising:
 placing the rotor with the sense magnet tray thereon in a mold and injection molding magnetic material into the sense magnet tray to form a sense magnet.   
     
     
         2 . The method of  claim 1  wherein molding magnetic material includes molding NdFeB material to form the sense magnet in the sense magnet tray and a yoke of ferromagnetic material is not provided in the sense magnet tray. 
     
     
         3 . The method of  claim 1  including providing features in the sense magnet tray that axially retain the sense magnet.