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. 16, 2019
Filed:
Aug. 04, 2017
Rolls-royce Plc, London, GB;
Michael P. Keenan, Sheffield, GB;
ROLLS-ROYCE plc, London, GB;
Abstract
A variable vane mechanism for adjusting the angle of stator vanes in a gas turbine engine is provided. The mechanism includes a circumferentially extending unison ring that is driven circumferentially around a casing by an actuator. The unison ring is connected to the stator vanes via levers such that the angle of the vanes changes with circumferential movement of the unison ring. The unison ring and the casing are each provided with at least one rigging hole in order to set the initial angle of the vanes. At least one of the unison ring and the casing are each provided with at least two rigging holes, so that the initial angle of the vanes can be adjusted by selecting different combinations of rigging holes. This may allow accumulations in tolerances to be compensated for and/or may allow the engine to be tested at different initial vane angles.