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:
Oct. 24, 2000
Filed:
May. 06, 1997
Mitchell Markow, Spring, TX (US);
Compaq Computer Corporation, Houston, TX (US);
Abstract
Piezoelectric speaker achieves radiation efficiency at low frequencies by using a piezoelectric speaker panel as a lumped parameter resonator. The speaker panel is mounted in a resonant system for generating translational motion. The resonant system includes suspension devices for suspending the panel to allow for translational motion of the panel and isolators for tuning the speaker panel to a predetermined frequency. At the predetermined frequency, the speaker panel achieves resonance in a low order mode, producing improved radiation efficiency at lower frequencies and translational motion of the panel not possible with a piezoelectric activator alone. The speaker panel may be included in a portable computer system, a desktop computer monitor, or other sound systems. In a portable computer system, a display screen or front speaker panel serves as a lumped parameter resonator, and the lid or rear speaker panel serves as a structure born vibration resonator. The front speaker panel may be driven or excited by coupling a piezoelectric actuator or a plurality of actuators to the front speaker panel, the rear speaker panel, or both panels. When the piezoelectric actuator is coupled to the rear speaker panel, a connection between the panels transfers the vibration energy to the front speaker panel. Further, the actuator or actuators used may be placed at suitable locations on one or both panels.