BRUSHLESS DC MOTOR WITH REDUCED THICKNESS, INCLUDING MAGNETIC POLE BASE AND POLE PLATE FORMED BY PUNCHING MAGNETICALLY CONDUCTIVE PLATES

摘要

PURPOSE: A brushless DC motor is provided to reduce parts count and costs by forming a magnetic pole base and a pole plate through a process of punching magnetically conductive plates. CONSTITUTION: A brushless DC motor comprises a pole plate(10') and a magnetic pole base(10) which are formed by punching magnetically conductive plates, respectively; a coil assembly(20) and a circuit board(40) mounted on the magnetic pole base; and a rotor(30) including a shaft(31) and a permanent magnet(32). The pole plate includes a magnetically conductive tube(12'), and a plurality of pole faces(11') arranged along a circumference of the magnetically conductive tube. The magnetic pole base includes a magnetically conductive tube(12), and a plurality of pole faces(11) arranged along a circumference of the magnetically conductive tube. The magnetically conductive tube of the pole plate and the magnetically conductive tube of the magnetic pole base form an axle tube. At least one bearing(121) is accommodated in the axle tube so as to rotatively support the shaft of the rotor. The pole faces of the magnetic pole base and the pole faces of the pole plate are arranged alternately with each other and disposed on a circumference of the axle tube.