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. 22, 1983
Filed:
Apr. 20, 1981
Applicant:
Inventor:
John A King, Martinsville, IN (US);
Assignee:
Harman International Industries, Northridge, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04R / ;
U.S. Cl.
CPC ...
181155 ;
Abstract
A direct radiating dynamic loudspeaker has an apertured impedance frontal loading element for improving its acoustic impedance. A planar sheet of nonrigid, fibrous air-permeable material has an apertured area and is positioned in front of the diaphragm of the loudspeaker. The sheet of air-permeable material is supported only at its periphery. A sheet of acoustically transparent material is bonded to the sheet of air-permeable material to cover the apertured area.
King, John. (1983). Loudspeaker having apertured acoustic impedance frontal loading element (U.S. Patent No. 4377219). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/4377219
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile