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:
Aug. 15, 2017
Filed:
Jan. 21, 2016
Panasonic Intellectual Property Management Co., Ltd., Osaka, JP;
Tsuyoshi Maeda, Hyogo, JP;
Yoshifumi Asao, Hyogo, JP;
Abstract
A noise reduction device includes a plurality of noise microphones, noise controller, and control speakers. Noise controller generates a control-sound signal to reduce a noise, at a control center of a control space, with the noise being detected by the plurality of noise microphones. Noise microphone disposed at a shorter distance from the control center than distance 'd' indicated by Relational Expression (1) is smaller in number than noise microphones disposed at longer distances than distance 'd' where “λ” is a wavelength corresponding to control upper-limit frequency “f” in noise microphones, “d” is a distance from the control center to control speakers, “t” is a control delay time in control speakers, and “v” is a sound speed.0+−λ/2  (1)