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:
Apr. 17, 1990
Filed:
Dec. 05, 1988
Joseph F Bader, Crete, IL (US);
Federal Signal Corporation, Oak Brook, IL (US);
Abstract
An acoustical system for generating loud sound levels over a wider bandwidth includes a generally cylindrically-shaped cavity formed of a wall member and having front and back ends. A baffle member is disposed to close the front end of the cavity, and a rear wall panel is disposed to close the back end of the cavity. A crystal/diaphragm driver assembly is formed of a bimorph piezoelectric crystal of a generally circular configuration and a generally conical-shaped diaphragm whose apex is fixedly attached to the center of the crystal. The driver assembly serves to convert electrical signals applied thereto into acoustical signals. The crystal is freely suspended at a first predetermined distance from the rear wall panel to form a rear Helmholtz loading chamber therebetween. The baffle member is spaced at a second predetermined distance from the crystal so as to form a front, outer enclosing chamber therebetween.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile