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:
Jun. 05, 1984
Filed:
Jun. 29, 1981
John M Treby, Bristol, GB;
Derek A Roberts, Bristol, GB;
Rolls-Royce Limited, London, GB;
Abstract
A fan drive system comprising a main drive shaft 13 which drives the fan through a frangible coupling 27 and an auxilliary drive shaft 30 which by-passes the coupling 27. The auxilliary shaft 30 is pre-twisted elastically in the opposite direction to the direction of rotation of the main shaft 13, and is held in the pre-twisted state by the coupling 27. When the coupling 27 disconnects the drive from the main shaft 13, for example when the fan becomes unbalanced and transverse loads exceed a predetermined magnitude, the auxilliary shaft 30 unwinds. Unwinding of the shaft 30 cushions the fan against suddenly applied loads when the coupling 27 breaks and also reduces the loads on the coupling 27 during normal balanced running.