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:
Apr. 28, 1992
Filed:
Sep. 27, 1989
Kazunari Furukawa, Hamamatsu, JP;
Yamaha Corporation, Hamamatsu, JP;
Abstract
An acoustic apparatus comprises a Helmholtz resonator which has a cavity and an open duct port for causing the cavity to communicate with an external region thereof and a vibrator which is arranged in the resonator to drive the resonator. In a first aspect, the open duct port comprises an air permeable member having a proper acoustic resistance and a viscoelastic member having no air permeability so that noise caused by an open duct resonant, wind noise, turbulence or the like is prevented. In a second aspect, a viscoelastic member is disposed at the mounting portion between the open duct port and a cabinet defining the cavity so that transmission to the cabinet of derivative vibration causing at the open duct port is prevented. In a third aspect, the portion, opposite to the open duct port, of an ornament grille attached to the front surface of the acoustic apparatus is given a larger air permeability than other portions of the grille so that wind noise when the grille is attached before the open duct port is prevented. Thus, noise generated when the resonator is driven is prevented or eliminated and distortion characteristics of the apparatus are improved.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile