| 摘要 |
<p>PURPOSE: To achieve the operation of a blower in high efficiency and low noise by positioning the input tip of a propeller fan and the opening point of a bell mouth on the same line. CONSTITUTION: A blower comprises a propeller fan(PF) which is rotated by a motor 30, a bell mouth 20 surrounding the PF 10 and a bracket 40 supporting the motor 30 fixed to the bell mouth 20. At this point, the fan rotation and the air-streaming operation noises of the PF 10 are generated in the blower. Therefore, the design factor of the bell mouth 20, together with the design factor of the PF 10 becomes important for determining the performance and the noise in the blower. The noise level and the performance of the blower caused by these changes are measured, and the blower is formed as follows. The inner diameter of the bell mouth is formed at 1.5±0.02 times the outer diameter of the PF 10. Furthermore, the width of the bell mouth 20 is formed at 0.468±0.068 times the width of the PF 10. Then, the curvature of the bell mouth 20 is formed at 0.032±0.014 times the outer diameter of the PF 10.</p> |
