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:
Jul. 10, 2012
Filed:
Jun. 22, 2007
Christopher J. Swanke, Cedar Rapids, IA (US);
Christopher J. Swanke, Cedar Rapids, IA (US);
Rockwell Collins, Inc., Cedar Rapids, IA (US);
Abstract
The present examples provide for the cancellation, or substantial reduction, of fan noise typically encountered in equipment cooling applications. Local audio nulls may be created by adjusting fan velocity and/or phase to cancel the fan noise near an operator. In a first example, phase and velocity of the fan may be controlled by feedback techniques. This technique utilizes feedback provided by a microphone located in the proximity of the operator to create an area of audio nulling of the fan noise. Local audio nulls may also be created by manipulating fan, phase and velocity by a controller that implements a process to create local audio nulls using the fixed position of equipment and the operator in the determination.