MOTOR FAN

摘要

PROBLEM TO BE SOLVED: To reduce wind noise caused by pressure pulsation in a motor fan. SOLUTION: This motor fan comprises impellers 6 rotatably driven by a motor 2, an air guide 8 having plural stationary vanes 7 arranged around the impellers 6 and a fan case 10 having a suction port 9 in the center and internally containing the air guide 8 and the impellers 6. The air guide 8 has a stationary cascade unit 14 formed by integrating plural stationary vanes 7. The stationary cascade unit 14 can be moved around the impellers 6 in the shaft direction. Shape of the air guide 8 can be changed. Thereby, wind noise is reduced.