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:
Nov. 21, 1978
Filed:
Jan. 31, 1977
Applicant:
Inventors:
Kenji Ogi, Tokyo, JP;
Masakatsu Sakamoto, Tokyo, JP;
Assignee:
Trio Kabushiki Kaisha, Tokyo, JP;
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
H05K / ;
U.S. Cl.
CPC ...
181156 ;
Abstract
In a bass-reflex type speaker system, in which sound signal waves radiating from the back of a speaker within a cabinet are emitted out through a hollow duct while the phase of the sound signal wave is reversed, the improvement comprising at least one dividing plate secured within the hollow duct and disposed parallel to the longitudinal direction of the duct or a hollow pipe with a diameter smaller than that of the duct, the hollow pipe being coaxially disposed within the hollow duct where the pipe may be made of sound absorbing material.