Improvements in gas turbine engines

1,141,001. Gas turbine engines. ROLLS-ROYCE Ltd. March 3, 1966 [March 3, 1965], No. 9166/65. Addition to 1, 041, 587. Heading F1G. [Also in Division H2] A gas turbine engine comprises a casing, a compressor or compressors, radial inlet guide vanes, and an A. C. machine which can operate as a generator, the stator of the machine being of annular form, the rotor being rotatable with the or one of the compressors, the A. C. machine being mounted forward of the or the first compressor. The engine shown is of the by-pass type comprising an air intake 2 defined between an outer casing 4 and an inner centre body 6, a low pressure compressor comprising rotor blade stages 8, 10 and stator blade stages 12, 14, a by-pass passage 18 and a passage 20 leading to a high pressure compressor, the two passages 18, 20 being separated by an annular wall 16 which is supported from the outer casing by radial vanes 22. The vanes 22 also support structure 24 which carries a forward bearing 26 in which the low pressure compressor rotor shaft 28 is mounted. The shaft 28 has a forward extension 30 on which is mounted the rotor 32 of the electrical generator, the stator 34 of the generator being secured to the rearward end of the centre body 6. The centre body 6 is supported from the casing 4 by radial vanes 36 through which pass the connections to the generator. The exciting winding of the stator is indicated by the two layers 40 and the output winding at 42. Holes 44 are provided through the stator rings for the flow of cooling air. An oil pump 38 is mounted within the forward part of the centre body being connected to the shaft extension 30 by means of a quill shaft. The generator is preferably of the A. C. homopolar type. The generator may be suitable for operation as a starter motor being supplied with A. C. from a battery through a suitable converter.