MOTOR

摘要

A small DC motor includes a motor frame having a cylindrical portion, the cylindrical portion having a constant thickness and having a cross section in a shape that comprises four sides and connecting portions, each of the connecting portions connecting adjacent two of the four sides and being located inward from a corresponding corner in a quadrangle comprising the four sides; and a magnet having a circumferential surface on an inside thereof and having conformable contact with the motor frame on an outside thereof.

主权项

1. A motor comprising:
a motor frame being a magnetic material and being a magnetic constituent portion of the motor, wherein the motor frame comprises four straight portions and four connecting portions, each of the connecting portions is located between adjacent two of the four straight portions; a magnet disposed on an inner surface of the motor frame, wherein the magnet include four magnetic poles and has an inner surface forming a circular opening; a rotor having a shaft and rotatably disposed in the circular opening of the magnet; an end cap attached to the motor frame; a commutator provided on the shaft; and an air gap provided between the inner surface of the magnet and the rotor, wherein each magnetic pole center of the magnet is corresponded to the connecting portions of the motor frame, and wherein each of the connecting portions of the motor frame has an arc shape and is a segment of a circle concentric with a center of the shaft.