초록 ▼

An electric motor driven blade pitch varying system for the fan blades of an unducted fan type aircraft gas turbine engine utilizes permanent magnet alternating current motors located in the oil sump region of the engine. An alternator driven by the engine generates unregulated variable frequency, v

An electric motor driven blade pitch varying system for the fan blades of an unducted fan type aircraft gas turbine engine utilizes permanent magnet alternating current motors located in the oil sump region of the engine. An alternator driven by the engine generates unregulated variable frequency, variable amplitude power which is rectified and placed on a DC bus. Controlled inverters convert the DC power on the bus to appropriate AC power for the motors. The system incorporates redundancy without significant weight penalty by providing alternators and motors dividing into two independent operating sections on common shafts. Separate electronic circuits are provided to supply power for each sectionalized motor or to rectify power from each alternator section. A common power bus may be used to couple the multiple motors and alternators. The common bus may alternatively receive power from tbe aircraft 400 Hz system or from on-board batteries.

대표청구항 ▼

Aircraft propulsion apparatus, comprising: (a) a gas generator for generating a gas stream and containing therein compressor means for driving a rotatable shaft; (b) first and second coaxially situated rotatable members; (c) a plurality of first and second rotor blades affixed to said first and seco

Aircraft propulsion apparatus, comprising: (a) a gas generator for generating a gas stream and containing therein compressor means for driving a rotatable shaft; (b) first and second coaxially situated rotatable members; (c) a plurality of first and second rotor blades affixed to said first and second rotatable members, respectively, said first and second rotor blades being positioned such that a gas stream, when produced by said gas generator, impinges thereon and causes said first and said second rotatable members to counterrotate; (d) a plurality of forward and aft variable pitch propulsor blades coupled to, and extending radially outwardly of, said first and second rotatable members, respectively; (e) gear means coupled to said propulsor blades; (f) electric motor means, including rotor means, mounted in stationary fashion relative to said rotatable members; (g) means coupling said rotor means to said gear means such that rotation of said rotor means effects a pitch change of said propulsor blades; (h) electrical generator means coupled to said rotatable shaft for generating electrical power; and (i) circuit means coupling said electrical generator means to said motor means, said circuit means including control means responsive to a desired propulsor blade pitch command for controlling said motor means to force each of said blades to a respective desired blade pitch.