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, 1977
Filed:
Jun. 01, 1976
Applicant:
Inventors:
William G Krawczak, White Bear Lake, MN (US);
William M Mularie, Stillwater, MN (US);
Assignee:
Minnesota Mining and Manufacturing Company, St. Paul, MN (US);
Primary Examiner:
Int. Cl.
CPC ...
H04R / ;
U.S. Cl.
CPC ...
1791 / ; 179120 ; 1791 / ; 181150 ; 181174 ;
Abstract
An electroacoustic loudspeaker having a rigid, light-weight diaphragm and a substantially closed loop magnet support of a magnetically permeable material having a channel-shaped cross-section and supported adjacent and spaced from the diaphragm with the open side of the channel facing the diaphragm. The magnet support carries a pair of magnets magnetized and positioned with opposite poles in spaced facing relation and a voice coil is secured to the diaphragm and lies in the gap between the magnets.