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:
Feb. 04, 2003
Filed:
Oct. 02, 2000
Fumihiko Yamaguchi, Akishima, JP;
Hideo Koreeda, Akishima, JP;
Foster Electric Company, Tokyo, JP;
Abstract
A diaphragm of electroacoustic transducer has an edge formed with alternately up-rolled and down-rolled portions with respect to vibration plane of the diaphragm and disposed at regular intervals in circumferential direction and with sloped-plane portions respectively connecting rims opposing above and below of adjacent ones of the up-rolled and down-rolled portions, the sloped-plane portions extending in respective tangential lines with respect to an inner periphery of the edge and intersecting the circumferential direction at an alternately opposite angle with respect to the vibration plane. The up-rolled and down-rolled portions of the edge provide an uneven shape varying in the stiffness of the portions upon vibration so as to cancel any difference in vibratory driving force from coils in a magnetic circuit, and any unbalanced vibratory driving force to the diaphragm due to magnetic flux distribution can be restrained by the uneven shape of the edge, so as to attain optimum rigidity of the diaphragm while rendering it to be well adaptable to dimensional minimization and thickness reduction.