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. 08, 2005
Filed:
Dec. 15, 1999
Jan Krueger, Stuttgart, DE;
Philip Leistner, Stuttgart, DE;
Jan Krueger, Stuttgart, DE;
Philip Leistner, Stuttgart, DE;
Abstract
The invention relates to a controlled acoustic wave guide configured as an elongated hollow chamber () which via an opening () in its first face end () is connected to a sound-conducting channel (). The longitudinal resonances of the hollow chamber () can be adjusted to a sound spectrum to be dampened. To this end diaphragm vibrations are detected by means of a microphone () which is positioned directly in front of the diaphragm () of at least one loud-speaker () at the second face-end () of the hollow chamber (). The microphone signal is then inverted using an amplifier () and fed back to the loud-speaker () after amplification in accordance with a sensor () signal characterizing the sound spectrum in the channel ().