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:
Feb. 11, 2014
Filed:
Mar. 18, 2010
Dale E. Evans, Derby, GB;
Michael R. Lawson, Derby, GB;
Dale E. Evans, Derby, GB;
Michael R. Lawson, Derby, GB;
Rolls-Royce PLC, London, GB;
Abstract
High bypass ratio turbofan propulsion engines are designed with a two-step approach to surviving foreign object damage to the fan assembly. First, a containment system encircling the fan assembly to capture any part of a released fan blade in the event of damage occurring, and two in order to cope with the vibrations resulting from a rotating unbalanced fan assembly the support structure for the bearing of the rotating assembly is constructed with frangible parts to introduce a snubber gap to permit the rotating, unbalanced fan assembly and bearing to orbit thereby to reduce the resulting vibrations. However, in the case of very wide chord fan assemblies, the largest acceptable snubber gap is insufficient to reduce the induced vibrations. The present solution is to incorporate into the containment system, and behind a fan track liner encircling the fan blades, at least one severance member having a cutting edge that will impact the tips of the blades of an orbiting fan assembly thereby to trim the mass distribution of the fan blades in order to reduce the vibrations caused by the out of balance forces.