| 摘要 |
PURPOSE:To effectively utilize a magnetic flux by forming a bobbin of molding resin filled with magnetic powder, and forming the outer periphery opposed to the pole of a rotor of the bobbin in an arcuate shape of the same diameter as the outer diameter of the pole of a core. CONSTITUTION:An arcuate-shaped magnet 2 which is magnetized in a radial direction is secured to the inner periphery of a rotor 1 of cup shape. A bobbin 4' is integrally molded with molding resin filled with insulating magnetic powder such as ferrite at the outer periphery of the salient pole winding of a core 3. The outer periphery 4' a opposed to the pole of the magnet 2 of the bobbin 4' is formed substantially in the same arcuate shape of the diameter as the outer diameter 3a of a pole piece of the core 3. Thus, a magnetic flux phi'2 which heretofore becomes leakage magnetic flux can be used as effective magnetic flux, thereby increasing the output. |
