Brushless DC motor power tool with combined PCB design

A power tool comprising:

• a brushless direct current (DC) motor having a rotor and a stator, wherein the rotor is coupled to a motor shaft to produce a rotational output, wherein the motor shaft is configured to rotate about a longitudinal axis, which extends through the motor shaft;
• a transmission coupled to the motor shaft configured to be driven by the rotational output;
• a combined printed circuit board (PCB) having a Hall sensor and power switching elements configured to drive the brushless DC motor,
• wherein the power switching elements are mounted on the combined PCB in a flat orientation and wherein the longitudinal axis extends through the combined PCB, and
• wherein the combined PCB includes a plurality of motor lead pads that each include an opening cut out from an outer peripheral edge of the combined PCB, each motor lead pad configured to receive a motor lead wire of the stator;
• and
• a heat sink attached to an end of the brushless DC motor, wherein the heat sink includes a through-hole,
• wherein the heat sink is located between the brushless DC motor and the combined PCB, and
• wherein at least one of the motor lead wires passes through the heat sink such that a portion of the at least one motor lead wire that is located in a plane defined by the heat sink is fully enclosed by the heat sink, wherein the plane defined by the heat sink is perpendicular to the longitudinal axis.

A power tool comprising:

• a brushless direct current (DC) motor having a rotor and a stator, wherein the rotor is coupled to a motor shaft to produce an output outside of a housing of the power tool, wherein the motor shaft is configured to rotate about a longitudinal axis, which extends through the motor shaft;
• a combined printed circuit board (PCB) having a Hall sensor, power switching elements configured to drive the brushless DC motor, and a through-hole,
• wherein the power switching elements are mounted on the combined PCB in a flat orientation and wherein the longitudinal axis extends through the through-hole, and
• wherein the combined PCB includes a plurality of motor lead pads that each include an opening cut out from an outer peripheral edge of the combined PCB, each motor lead pad configured to receive a motor lead wire of the stator, wherein the motor lead wires are electrically coupled to the power switching elements to allow the power switching elements to directly drive the brushless DC motor via the motor lead wires;
• and
• a heat sink in thermal contact with a plurality of the power switching elements, wherein the heat sink includes an inner edge and an outer edge, the inner edge located radially closer to the longitudinal axis than the outer edge, at least one of the inner edge and the outer edge having a shape that is substantially parallel with a portion of a circumference of the combined PCB,
• wherein the Hall sensor is located radially outward of the through-hole and radially inward of the inner edge of the heat sink,
• wherein the heat sink is located between the brushless DC motor and the combined PCB, and
• wherein at least one of the motor lead wires passes at least partially in a direction parallel to the longitudinal axis along a thickness of the heat sink from one axial side of the heat sink to the other axial side of the heat sink.