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. 15, 1994
Filed:
Jun. 24, 1992
Applicant:
Inventors:
Kunio Mitobe, Yamagata, JP;
Yutaka Moriyama, Yamagata, JP;
Assignees:
Tohoku Pioneer Electronic Corp., Tendo, JP;
Pioneer Electronic Corp., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04R / ;
U.S. Cl.
CPC ...
381199 ; 381204 ;
Abstract
A magnetic circuit has a yoke base, a pole formed on the yoke base, an annular magnet mounted on the yoke base, an annular plate having an inclined surface mounted on the magnet. The annular plate has an inwardly downwardly curved sectional shape toward a periphery. A frame for a conical diaphragm is secured to the plate. A plurality of platforms each having a flat surface are formed on the inclined surface, and a plurality of staking projections are formed on the flat surfaces of the platforms. The frame is secured to the plate by staking the staking projections.