The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 28, 2012
Filed:
Oct. 30, 2007
Seiji Shirahama, Aichi, JP;
Kazuo Ogino, Aichi, JP;
Yasuji Tsubakishita, Aichi, JP;
Akira Sadamoto, Aichi, JP;
Seiji Shirahama, Aichi, JP;
Kazuo Ogino, Aichi, JP;
Yasuji Tsubakishita, Aichi, JP;
Akira Sadamoto, Aichi, JP;
Panasonic Corporation, Osaka, JP;
Abstract
A centrifugal fan used as a ventilating fan is provided which can increase a range of frequencies of noises in which noises can be suppressed and can adjust frequencies of noises at which noises can be suppressed. The centrifugal fan includes, in an outer casing, a motor that couples an impeller, a casing that surrounds a periphery of the impeller and has a bell-mouthed suction port on one side, and a bell-mouthed orifice that has an opening that is concentric with the suction port and has a diameter equal to or smaller than that of the suction port, wherein a member closing a clearance portion between an end of the orifice and the casing is a noise absorbing structural material, and a space formed by the orifice is a rear air layer, thereby forming a resonance type noise absorbing structure.