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:
Nov. 21, 2000
Filed:
Mar. 17, 1998
Applicant:
Inventor:
Rudolf Maier, Miesbach, DE;
Assignee:
DaimlerChrysler AG, , DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
A61F / ; G10K / ; H03B / ;
U.S. Cl.
CPC ...
381 7114 ; 381 718 ;
Abstract
An active acoustic resonator is provided for noise reduction, with a sound generator having a membrane, with a sensor for measuring the membrane motion, with an actuator for driving the membrane, as well as with a controller receiving the measured signal of the sensor and generating control signals for the actuator. A transfer function (F.sub.R) of the controller is proportional to a quotient, whose numerator (F.sub.BP) has the transfer behavior of a band pass filter with variable center frequency (f.sub.0), and whose denominator represents the transfer function (F.sub.U) of the actuator.