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:
Dec. 13, 1994
Filed:
Jun. 02, 1993
Francis E Byrnes, White Plains, NY (US);
Timothy A Krauss, Harwinton, CT (US);
David N Schmaling, Oxford, CT (US);
United Technologies Corporation, Hartford, CT (US);
Abstract
A flexbeam for a soft inplane bearingless main rotor assembly has six spanwise regions: a hub attachment region; a first tapered region; a second tapered region; a pitch region; a tapered outboard transition region; and a main rotor blade, torque tube attachment region. One described embodiment of the flexbeam is fabricated from continuous unidirectional fiberglass plies having a 0.degree. fiber orientation, unidirectional fiberglass plies of varying lengths having a 0.degree. fiber orientation, and graphite cross plies having .+-.45.degree. fiber orientations. The pitch region is formed solely by the continuous fiberglass plies which define a rectangular cross section therefor. The second tapered region is formed solely by the continuous fiberglass plies and the fiberglass plies of varying lengths. The ends of the fiberglass plies terminate in a distributed arrangement in the second tapered region to define the taper thereof. The remaining regions of the flexbeam are formed by interleaved combinations of the continuous fiberglass plies, the fiberglass plies of varying length, and the graphite cross plies of varying length. Ends of the graphite cross plies terminate in a distributed arrangement in the first tapered region to partially define the taper thereof. Ends of the fiberglass plies and the graphite cross plies terminate in a distributed arrangement in the tapered outboard transition region to define the taper thereof. The distributed arrangements of ply endings cause kick loads in the flexbeam to be distributed relatively uniformly into the ply buildups.