| 摘要 |
PROBLEM TO BE SOLVED: To provide a motor producing a large output and an increased inertia with a small size while enhancing rotation efficiency by employing an outer rotor structure and an inboard rotor structure and durable against an impact unique to a motor for tool. SOLUTION: A shaft 1 has one and the other ends supported rotatably by first and second brackets 5a and 5b, respectively. The first bracket is integrally provided with a portion 10 extending to the second bracket side along the circumferential surface of the shaft. A stator 4 is fitted fixedly to the outer circumferential surface of the extending portion of the shaft. A rotor magnet 22 is provided oppositely to the outer circumferential surface of the stator 4 through a gap. A rotor 2 comprises a rotor holder 21 having an inner surface for fixing the rotor magnet, one open end and the other end fixed to a part of the shaft between the end face of the extending portion of the first bracket and the second bracket. A first bearing 16 is interposed between the open end of the rotor holder and the first bracket. COPYRIGHT: (C)2007,JPO&INPIT |
