| 摘要 |
PROBLEM TO BE SOLVED: To make compatible both large downsizing and reduction in uneven rotation while keeping output performance in a DC brushless motor. SOLUTION: The DC brushless motor comprises a stator composed of electromagnets, and a magnet-integrated rotor arranged at the center and having permanent magnets at its external periphery. The permanent magnet has the product of maximum energy of not smaller that 111kj/m<SP>3</SP>and not larger than 239kj/m<SP>3</SP>, is formed into an integrated ring shape, and is a bonded magnet of an anisotropy rare earth group formed thin in thickness. The stator has 12 poles in tooth number, and when setting the radius of the stator as r, the radial thickness of the stator as t, the radial thickness of the bonded magnet of the anisotropy rare earth group as d, and the radius of the magnet-integrated rotor as R, a ratio d/r between the magnet thickness and the stator radius is set not smaller than 0.01 and smaller than 0.10, a ratio R/t between the rotor radius and the stator thickness is set not smaller than 2.0 and not larger than 3.5. COPYRIGHT: (C)2007,JPO&INPIT |
