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:
Mar. 01, 2016
Filed:
Oct. 15, 2014
Masahiro Ishida, Kanagawa, JP;
Toshihiro Shimada, Tokyo, JP;
Naoki Matsuda, Kanagawa, JP;
RICOH COMPANY, LTD., Tokyo, JP;
Abstract
A sound absorber includes a duct member constituting a resonance pathway, the duct member including a pathway portion communicating ends of the duct member; a base member including a concave portion; and a cover member including a neck in which to insert the duct member. The cover member covers the concave portion of the base member, and the cover member combined with the base member forms a resonance space having a volume V. The resonance pathway has dimensions of a length LH and a cross-sectional area SH and communicates the resonance space and an exterior of the sound absorber. The sound absorber has a resonance frequency fH determined by fH=(c/2π)·(SH/V·LH)and absorbs sound having the resonance frequency fH, where c represents sound velocity.