| 摘要 |
PROBLEM TO BE SOLVED: To reduce the thickness of a motor, suppress the vibration caused by the torque ripple and, further, obtain the large effective blowing width of a blower by a method in which the number of core teeth and the number of poles are determined so as to set the summation of these numbers within a specific range. SOLUTION: The core teeth of a stator core and permanent magnets are made to face each other with very small gaps therebetween. The number of the core teeth and the number of the poles are determined so as to set the summation of those numbers within a range of 25-60. As a brushless DC motor M is an outer-rotor type motor and its thickness is very small in comparison with the thickness of a conventional motor, the axial direction length of a circulation fan 45' can be extended. Therefore, if an outer frame 45 having a same horizontal length is used, the longer lateral length of the air passage of an air conditioner is available in comparison with that of a conventional air conditioner. With this constitution, the thickness of the brushless motor can be reduced and the rotation vibration can be suppressed and, further, the large effective blowing width of a blower can be obtained. |
