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:
Apr. 10, 2012
Filed:
Aug. 23, 2007
Michael C. Roberts, Bristol, GB;
Michael C. Roberts, Bristol, GB;
Rolls-Royce PLC, London, GB;
Abstract
A firtree profile, for example on a component of a gas turbine engine, is formed in a two-stage process. In one stage, an intermediate profile is formed, for example by a mechanical machining operation such as grinding. Subsequently, in a second stage, loaded flanksof the profile are formed by an electric discharge machining operation performed on the intermediate profile. Alternatively, the electric discharge machining operation may be performed first to create the intermediate profile, and subsequently transition regions, such as fillets, may be formed in a mechanical or chemical material removing operation. In the resulting profile, surfaces, such as the loaded flanks, which must be finished to tight tolerances, but which are subjected to relatively low bending stresses, are formed by the electric discharge machining operation, which leaves a re-cast layer. In regions subjected to higher bending stress, such as regionsof the fillets, are formed by mechanical or chemical metal removal techniques, and so do not have the re-cast layer