Combination structure between stator and rotor in a brushless motor

A brushless motor, comprising:

• a stator including a stator core and a plurality of winding teeth evenly distributed on the stator core;
• and
• a rotor rotatably disposed within the stator with the winding teeth facing the rotor, the rotor including a rotor core and a plurality of magnets evenly distributed around the rotor core,
• wherein a first symmetry axis is defined passing through a center of a first one of the magnets to a center of the rotor, and a second symmetry axis is defined passing between adjacent ones of the magnets to the center of the rotor,
• wherein a first distance between an outer surface of the rotor to a surface of a first one of the winding teeth when the first axis is aligned with the first winding tooth is smaller than a second distance between the outer surface of the rotor to the surface of the first winding tooth when the second axis is aligned with the first winding tooth,
• wherein the rotor and the stator are configured such that the first and second distances satisfy:
• 1.5≤g2/g1≤3.5
• where g1 is the first distance and g2 is the second distance,
• wherein magnets are disposed in mounting slots evenly distributed around the rotor core,
• wherein a length of each mounting slot is greater than a length of each respective magnet, and each magnet is disposed at a center of each mounting slot,
• wherein flux barriers are at each side of each respective mounting slot,
• wherein each winding tooth includes a coil wound portion and a front portion facing the rotor at an end of the coil wound portion,
• wherein a surface of the front portion has an arc segment at a center part and two straight line segments connected to respective ends of the arc segment, and
• wherein a length of each straight line segment, a width of the winding portion, and a width of the front portion are configured to satisfy:
• (c−b)/2≤a≤c/2
• where ‘a’ is the length of each straight line segment, ‘b’ is the width of the winding portion, and ‘c’ is the width of the front part.