BRUSHLESS MOTOR SYSTEM FOR POWER TOOLS

摘要

A power tool is provided including a tool housing and a brushless DC (BLDC) motor disposed within the tool housing. The motor includes a stator assembly and a rotor assembly having a rotor lamination stack mounted on a rotor shaft to rotate therewith. The power tool also includes a power module for driving the motor, which includes: a printed circuit board, power switches operatively connected to the motor disposed on a first surface of the printed circuit board, positional sensors disposed on a second surface of the printed circuit board around a periphery of a center portion of the printed circuit board, and a heat sink having a substantially planar surface facing the second surface of the printed circuit board and disposed between the motor and the printed circuit board. The heat sink includes a through-hole therein sized to axially expose the positional sensors in the direction of the motor.

主权项

1. A power tool comprising:
a tool housing; a brushless DC (BLDC) motor disposed within the tool housing, the motor including a stator assembly, and a rotor assembly rotatably disposed within the stator assembly, the rotor assembly comprising a rotor lamination stack mounted on a rotor shaft to rotate therewith and a fan in rotational connection with the rotor shaft; and a power module for driving the motor, comprising: a printed circuit board, a plurality of power switches operatively connected to the motor disposed on a first surface of the printed circuit board, a plurality of positional sensors disposed on a second surface of the printed circuit board around a periphery of a center portion of the printed circuit board, and a heat sink having a substantially planar surface facing the second surface of the printed circuit board and disposed between the motor and the printed circuit board, the heat sink having a through-hole therein sized to axially expose the positional sensors in the direction of the motor.