| 摘要 |
PROBLEM TO BE SOLVED: To provide an electric blower with reduced noise, suppressing generation of air flow sound without deterioration in the efficiency of an electric blower, and significantly reducing operation noise and target high-frequency sound. SOLUTION: The electric blower includes an electric motor 4, an impeller 6, an air guide 10, a fan case 12, and a soundproof cylinder 16 covering the electric motor 4 and the fan case 12. In the soundproof cylinder 16, a wall 14a with an exhaust port 15 has a multiple wall structure, a partition 17 is disposed in a whole circumference of a space between walls at predetermined position from an end part of the wall 14a, and an air permeable lid 18 is disposed on the same plane of an end part of the wall 14a. The generated air flow is thereby discharged to smoothly flow along the lid 18 and reduce the air current sound. The high-frequency sound caused by pulsation of the airflow is largely reduced by resonance effect in a space 13 formed by the multiple walls of the soundproof cylinder 16 and the partition 17. Transmission loss becomes large in the multiple wall soundproof cylinder 16, and the operation noise transmitted through the soundproof cylinder 16 is significantly reduced. COPYRIGHT: (C)2009,JPO&INPIT
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