A motor. The motor includes a stator, a rotor, a top magnetic structure, and a bottom magnetic structure. The stator is disposed in a frame. The rotor is also disposed in the frame, corresponding to the stator. The rotor comprises a shaft, extended axially from the rotor. The shaft does not contact the stator or the frame. The bottom magnetic structure is at the bottom of the frame. The top magnetic structure is on the top of the frame. The top and bottom magnetic structures are opposite to each other in an axial direction. Magnetic attraction generated between the first magnetic structure and the second magnetic structure attracts and positions the shaft therebetween such that the first magnetic structure, the second magnetic structure, and the shaft are coaxially aligned.