| 摘要 |
PROBLEM TO BE SOLVED: To obtain satisfactory cooling efficiency and reduce the size of a motor for manufacturing at a low cost by fitting a fan mechanism on the outer rotor itself of an outer rotor brushless motor. SOLUTION: A plurality (for example, 6pcs) of riser tabs 12 serving as blades are formed on the yoke upper surface of an outer rotor 1, and a lid 2 which is fixed and supported on the riser tabs 12 is formed on the yoke upper surface 11 side. The lid 2, which is of roughly disc shape whose central part protrudes, is formed into almost the same size as the yoke upper surface 11. Especially, an inflow opening 2A which introduces wind for outside cooling is opened at its central part. When a motor is operated, the outer rotor 1 starts its rotation, therefore, the riser tabs 12 themselves of the yoke upper surface 11 of the rotor 1 act as the blades of a fan. As a result, air taken from the inflow opening 2A of the lid 2 passes through a hole 11A so as to be blown into the coil 3A on stator 3 side, thus it is possible to dissipate generated Joule heat effectively. |
