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:
Dec. 11, 2007
Filed:
Oct. 31, 2003
Applicant:
Ewald Frasl, Biedermannsdorf, AT;
Inventor:
Ewald Frasl, Biedermannsdorf, AT;
Assignee:
NXP B.V., Eindhoven, NL;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04R 7/14 (2006.01);
U.S. Cl.
CPC ...
Abstract
A membrane () has a membrane axis () and a middle area (), a central cup-shaped depression () being provided around said membrane axis (), which depression () preferably has a connecting channel (), wherein the middle area () comprises groups of stiffening grooves () which extend parallel to radial directions and of which a first group of long stiffening grooves () extends up to the depression (), said connecting channel () issuing into two of the long stiffening grooves (), thus interconnecting these two long stiffening grooves ().