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:
Aug. 16, 1983
Filed:
Apr. 09, 1981
Tsutomu Kakiuchi, Toda, JP;
Yoshiyuki Kamon, Yokohama, JP;
Sony Corporation, Tokyo, JP;
Abstract
A speaker unit for headphones including a magnetic circuit which has a magnetic gap and including a diaphragm which is moveable to generate sound in response to energy applied to a coil wound on a bobbin which is connected to the diaphragm and mounted within the magnetic gap and including a frame for supporting the magnetic circuit and the diaphragm and a protecting means mounted at the front of the diaphragm and having projections so as to engage the diaphragm near the region where the bobbin is mounted so as to limit the maximum motion of the diaphragm and the protecting means formed with openings such that the protector prevents the bobbin from moving completely out of the magnetic gap. The invention is applicable to speaker units for open air type headphones, for example.