| 摘要 |
PROBLEM TO BE SOLVED: To prevent the occurrence of rasping noise accompanied by the vibration of a stator. SOLUTION: In a brushless motor equipped with a stator unit 20, a bottomed cylindrical shaped case 12 accommodating the stator unit 20, and a rotor 30 rotatably arranged insides the stator unit 20, a plurality of radial beads 19 are arranged at a constant interval in the circumferential direction on the bottom wall 15 of the case 12 and the radial beads 19 are fitted in between the salient pole portions 27, 27 of the stator unit 20. The radial beads cause vibration hard to be transmitted, and even if the vibration of the stator unit is transmitted to the bottom wall, the generation of sounds caused by the amplification or the resonance of the vibration can be suppressed, preventing the generation of rasping noise. The radial beads are fitted in between the adjacent salient pole portions, securing the positioning and rotation stop relative to the case of the stator unit, with improved assembling accuracy and mechanical strength or the like of the brushless motor. COPYRIGHT: (C)2007,JPO&INPIT |
