Mechanical drive device for driving the high pressure sub assembly of an airplane engine

{
  "publication_number": "US9027355B2",
  "country": "US",
  "kind": "B2",
  "title": "Mechanical drive device for driving the high pressure sub assembly of an airplane engine",
  "abstract": "A manual mechanical drive to a high pressure sub assembly of a turbojet during endoscopic inspection of the high pressure turbine is provided. A coupling element suitable for coupling with an external actuator such as a crank handle is fitted on the axis of an alternator that is normally driven mechanically via the high pressure sub assembly, thereby providing a coupling suitable for driving said high pressure sub assembly.",
  "claims": [
    "1. A mechanical drive device for driving a high pressure sub assembly of an airplane engine in order to inspect a rotary portion thereof, said high pressure sub assembly being mechanically coupled via a gearbox to an alternator, wherein a first coupling element for coupling with an external actuator is accessible on and provided on a rotor shaft of said alternator aligned with an axis of said alternator, and is usable as a coupling to enable driving of said high pressure sub assembly, wherein said first coupling element is disposed on a first end of said rotor shaft, and wherein a second end of the rotor shaft of said alternator includes a second coupling element which is coupled to a third coupling element provided at a first end of a drive shaft of said gearbox aligned with said axis such that said first coupling element, said rotor shaft of said alternator, and said drive shaft of said gearbox are rotatable together.",
    "2. A mechanical drive device according to claim 1, wherein the first end of the rotor shaft of said alternator projects outside of a casing of the alternator, and the first coupling element is disposed outside of the casing of said alternator.",
    "3. A mechanical drive device according to claim 1, wherein when said alternator is removed from said gearbox, said third coupling element of said drive shaft is accessible to enable said external actuator to be coupled thereto.",
    "4. A mechanical drive device according to claim 3, wherein said second coupling element and said third coupling element are situated inside said gearbox.",
    "5. A mechanical drive device according to claim 3, wherein said second coupling element and said third coupling element are situated inside a casing of said alternator.",
    "6. A mechanical drive device for driving a high pressure sub assembly of an airplane engine in order to inspect a rotary portion thereof, said high pressure sub assembly being mechanically coupled via a gearbox to an alternator, wherein a coupling element for coupling with an external actuator is accessible on and provided on a common shaft of said alternator and of said gearbox, and is usable as a coupling to enable driving of said high pressure sub assembly, and wherein a first end of said common shaft is provided with said coupling element.",
    "7. A mechanical drive device according to claim 1, further comprising a gearwheel provided on said drive shaft of said gearbox, said gearwheel meshing with a stepdown mechanism disposed inside said gearbox.",
    "8. A mechanical drive device according to claim 6, further comprising a gearwheel provided on said common shaft, said gearwheel meshing with a stepdown mechanism.",
    "9. A mechanical drive device according to claim 6, wherein the first end of the common shaft projects outside a casing of said gearbox or outside a casing of said alternator."
  ],
  "description_excerpt": "The invention relates to a mechanical drive device, e.g. operable by means of a crank handle, for turning the rotating part of the high pressure sub assembly of an airplane engine while inspecting said sub assembly rotating part, e.g. for the purpose of detecting defects such as cracks on the blades of a rotor of said high pressure sub assembly, in particular the rotor of the high pressure compressor. The type of inspection that is more particularly concerned is conventional endoscopic inspection, which requires the high pressure sub assembly rotating part to be turned slowly in order to inspect its blades one by one. The invention relates more particularly to an improvement taking better advantage of the equipment that is associated with the gearbox that is coupled to the shaft of such a high pressure sub assembly for the purpose of driving accessories.\n\nIn an airplane turbojet, the high pressure sub assembly includes the high pressure compressor that provides air under pressure to the combustion chamber, and the high pressure turbine that turns a shaft that is itself coupled to the high pressure compressor in order to drive it. During maintenance operations, it is necessary to inspect the state of the rotary portions, in particular the rotor blades, with inspection initially being visual. This is commonly done endoscopically. The end of an endoscope is inserted into the casing of the high pressure sub assembly and the rotor is turned slowly in order to be able to identify visible defects.",
  "cpc": [
    "F02C 7/32",
    "F01D 25/36",
    "F05D 2220/764",
    "F05D 2260/4031",
    "F16B 2200/10",
    "H02K 7/1823",
    "H02K 7/1861",
    "Y02T 50/60",
    "Y02T 50/671",
    "Y10T 403/7039"
  ],
  "ipc": [
    "F01D 25/36",
    "F02C 7/32",
    "H02K 7/18"
  ],
  "assignees": [
    "COLOTTE BAPTISTE BENOÍT",
    "GALIVEL JEAN PIERRE ELIE",
    "GAULLY BRUNO ROBERT",
    "SNECMA"
  ],
  "inventors": [
    "COLOTTE BAPTISTE BENOÍT",
    "GALIVEL JEAN PIERRE ELIE",
    "GAULLY BRUNO ROBERT"
  ],
  "filing_date": "2010-10-27",
  "publication_date": "2015-05-12",
  "grant_date": "2015-05-12",
  "priority_date": "2009-10-29",
  "application_number": "US-91340910-A",
  "family_id": "42164106",
  "citations": [
    "EP1338773A2",
    "EP1876337A1",
    "US2006099095A1",
    "US2006248900A1",
    "US2006260323A1",
    "US2008006023A1",
    "US2010242496A1",
    "US2012026491A1",
    "US4733155A",
    "US4733529A",
    "US5813829A"
  ]
}