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:
Mar. 09, 2004
Filed:
Jul. 29, 2002
Richard J Flatman, Derby, GB;
Christopher Freeman, Nottingham, GB;
Rolls-Royce plc, London, GB;
Abstract
A variable cycle gas turbine engine ( ) includes first and second compressors ( ), combustion apparatus ( ) and first and second turbines ( ) operable to drive the first and second compressors ( ) respectively via interconnecting shafts. The capacity of one of the turbines ( ) may be varied, for example by means of guide vanes ( ) which can be adjusted to reduce or increase a throat area ( ) through which air leaves the guide vanes to impact the turbine. The capacity of the turbine may be increased at low engine speeds, to reduce the pressure ratio across the turbine and across the compressor ( ) which it drives, thereby improving the surge margin of the compressor.