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:
May. 10, 1994
Filed:
Apr. 16, 1992
Charles A Yoerkie, Jr, Newington, CT (US);
William A Welsh, North Haven, CT (US);
Thomas W Sheehy, Hamden, CT (US);
United Technologies Corporation, Stratford, CT (US);
Abstract
An active noise control (ANC) system for a helicopter that is operative to effectively nullify one or more high frequency vibrations emanating from the main transmission gearbox thereof at the gearbox/airframe interface, thereby significantly reducing the interior noise levels of the helicopter, that is design optimized to minimize the number of actuators required, and that is design optimized to minimize contamination forces arising from operation of the system actuators. The ANC system includes modified transmission beams that are mechanically stiffened to function as rigid bodies with respect to the one or more of the high frequency vibrations, a plurality of actuators disposed in combination with the modified transmission beams, a plurality of sensors disposed in combination with the modified transmission beams in a collinear, spaced apart functional correlation with respective actuators, and controllers interconnecting individual actuators with respective functionally correlated sensors.