Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
  • F02C7/00—Features, components parts, details or accessories, not provided for in, or of interest apart form groups F02C1/00 - F02C6/00; Air intakes for jet-propulsion plants
  • F02C7/04—Air intakes for gas-turbine plants or jet-propulsion plants
  • F02C7/045—Air intakes for gas-turbine plants or jet-propulsion plants having provisions for noise suppression
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64D—EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
  • B64D27/00—Arrangement or mounting of power plants in aircraft; Aircraft characterised by the type or position of power plants
  • B64D27/02—Aircraft characterised by the type or position of power plants
  • B64D27/16—Aircraft characterised by the type or position of power plants of jet type
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64D—EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
  • B64D29/00—Power-plant nacelles, fairings, or cowlings
  • B64D29/06—Attaching of nacelles, fairings or cowlings
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64D—EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
  • B64D33/00—Arrangements in aircraft of power plant parts or auxiliaries not otherwise provided for
  • B64D33/02—Arrangements in aircraft of power plant parts or auxiliaries not otherwise provided for of combustion air intakes
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
  • F01D11/00—Preventing or minimising internal leakage of working-fluid, e.g. between stages
  • F01D11/08—Preventing or minimising internal leakage of working-fluid, e.g. between stages for sealing space between rotor blade tips and stator
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
  • F01D25/00—Component parts, details, or accessories, not provided for in, or of interest apart from, other groups
  • F01D25/24—Casings; Casing parts, e.g. diaphragms, casing fastenings
  • F01D25/243—Flange connections; Bolting arrangements
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02K—JET-PROPULSION PLANTS
  • F02K1/00—Plants characterised by the form or arrangement of the jet pipe or nozzle; Jet pipes or nozzles peculiar thereto
  • F02K1/78—Other construction of jet pipes
  • F02K1/82—Jet pipe walls, e.g. liners
  • F02K1/827—Sound absorbing structures or liners
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02K—JET-PROPULSION PLANTS
  • F02K3/00—Plants including a gas turbine driving a compressor or a ducted fan
  • F02K3/02—Plants including a gas turbine driving a compressor or a ducted fan in which part of the working fluid by-passes the turbine and combustion chamber
  • F02K3/04—Plants including a gas turbine driving a compressor or a ducted fan in which part of the working fluid by-passes the turbine and combustion chamber the plant including ducted fans, i.e. fans with high volume, low pressure outputs, for augmenting the jet thrust, e.g. of double-flow type
  • F02K3/06—Plants including a gas turbine driving a compressor or a ducted fan in which part of the working fluid by-passes the turbine and combustion chamber the plant including ducted fans, i.e. fans with high volume, low pressure outputs, for augmenting the jet thrust, e.g. of double-flow type with front fan
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64D—EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
  • B64D33/00—Arrangements in aircraft of power plant parts or auxiliaries not otherwise provided for
  • B64D33/02—Arrangements in aircraft of power plant parts or auxiliaries not otherwise provided for of combustion air intakes
  • B64D2033/0206—Arrangements in aircraft of power plant parts or auxiliaries not otherwise provided for of combustion air intakes comprising noise reduction means, e.g. acoustic liners
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64D—EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
  • B64D33/00—Arrangements in aircraft of power plant parts or auxiliaries not otherwise provided for
  • B64D33/02—Arrangements in aircraft of power plant parts or auxiliaries not otherwise provided for of combustion air intakes
  • B64D2033/0266—Arrangements in aircraft of power plant parts or auxiliaries not otherwise provided for of combustion air intakes specially adapted for particular type of power plants
  • B64D2033/0286—Arrangements in aircraft of power plant parts or auxiliaries not otherwise provided for of combustion air intakes specially adapted for particular type of power plants for turbofan engines
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2220/00—Application
  • F05D2220/30—Application in turbines
  • F05D2220/32—Application in turbines in gas turbines
  • F05D2220/323—Application in turbines in gas turbines for aircraft propulsion, e.g. jet engines
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2230/00—Manufacture
  • F05D2230/50—Building or constructing in particular ways
  • F05D2230/53—Building or constructing in particular ways by integrally manufacturing a component, e.g. by milling from a billet or one piece construction
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2250/00—Geometry
  • F05D2250/70—Shape
  • F05D2250/75—Shape given by its similarity to a letter, e.g. T-shaped
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2260/00—Function
  • F05D2260/30—Retaining components in desired mutual position
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2260/00—Function
  • F05D2260/30—Retaining components in desired mutual position
  • F05D2260/31—Retaining bolts or nuts
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2260/00—Function
  • F05D2260/96—Preventing, counteracting or reducing vibration or noise
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2300/00—Materials; Properties thereof
  • F05D2300/10—Metals, alloys or intermetallic compounds
  • F05D2300/12—Light metals
  • F05D2300/121—Aluminium
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2300/00—Materials; Properties thereof
  • F05D2300/10—Metals, alloys or intermetallic compounds
  • F05D2300/13—Refractory metals, i.e. Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, W
  • F05D2300/133—Titanium
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2300/00—Materials; Properties thereof
  • F05D2300/60—Properties or characteristics given to material by treatment or manufacturing
  • F05D2300/603—Composites; e.g. fibre-reinforced
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T50/00—Aeronautics or air transport
  • Y02T50/60—Efficient propulsion technologies, e.g. for aircraft

Definitions

• the invention relates to an air intake of an aircraft turbojet engine nacelle.
• the invention relates to a particular form of the structure of the air inlet for its attachment to a nacelle fan casing according to a radial interface surface.
• An aircraft is driven by several turbojet engines each housed in a nacelle housing a set of ancillary actuating devices related to its operation and providing various functions when the turbojet engine is in operation or stopped.
• a turbojet engine nacelle generally has a substantially tubular structure which extends along a longitudinal axis from upstream to downstream, depending on the direction of flow of the air flow.
• the nacelle comprises an air inlet upstream of the turbojet engine, a median section intended to surround a fan of the turbojet engine, a downstream section surrounding the combustion chamber of the turbojet engine, intended to channel the secondary air stream and possibly incorporating d thrust reversal, and is generally terminated by an ejection nozzle whose output is located downstream of the turbojet engine.
• the air inlet comprises in particular an annular entry lip forming a leading edge which is adapted to allow optimal capture of the air necessary for the supply of the blower and the internal compressors of the turbojet engine. Downstream of the lip, an acoustic downstream structure properly channels the air to the vanes of the blower.
• This downstream structure of the air inlet comprises in particular an annular duct whose structure is particularly adapted to attenuate the noise emitted by the turbojet engine, also called the acoustic air inlet shell.
• the ferrule is mainly constituted by an acoustic sandwich structure comprising, an acoustically permeable skin also forming an inner skin of the air duct, an impervious outer skin, and a honeycomb core of predetermined height connecting the two skins, this core being generally Honeycomb type, the assembly constituting an acoustic damper.
• the shell is assembled in its downstream part with the fan casing according to a clamping plane by means of a device comprising fasteners connecting vis-à-vis the flange of the air intake ferrule and the housing.
• the clamping plane For safety reasons in case of loss of a blade of the blower, the clamping plane must be positioned upstream of the blade of the plane of the blower.
• the document FR-A-2767560 describes and represents a device comprising a first L-shaped flange integral with the fan casing and a second L-shaped flange, an axial base of which is riveted to the outer skin of the shell and a flange of which radial is attached to the first flange.
• This type of device has the disadvantage of having to bind the inner skin and the outer skin of the ferrule to associate them in one to the attachment area of the second flange L.
• FR-A-2869360 which proposes a second L-shaped flange attached to the outer skin of the ferrule
• this type of device has the disadvantage of perforating the outer skin.
• the quality of the fixation is difficult to verify and the acoustic cavity between the outer skin and inner skin is impaired reducing the efficiency of the area.
• This document also proposes an L-flange directly glued or made to the back of the outer skin of the ferrule, however this device has the risk of punching the cellular material connecting the inner skin and the outer skin during mechanical deformations induced by the operation of the turbojet.
• Also known device described and shown in FR-A-2959726 which comprises a first flange which is integral with the housing and a second flange which is integral with the ferrule.
• This device provides advantages by proposing an L-flange bonded to the ferrule and which is offset to the back of the outer skin of the ferrule which avoids impacting the acoustic treatment of said shell, but is difficult and expensive to achieve.
• the present invention aims in particular to solve these disadvantages and relates for this purpose to a device for fixing a downstream end of an air inlet on a fan casing of an aircraft turbojet engine nacelle, the air inlet comprising an acoustic ferrule having an annular shape which extends axially from upstream to downstream along a longitudinal axis and which is delimited radially by an internal skin and an external skin trapping an acoustic panel, the device comprising a first flange which is secured to the housing, and a second L-shaped flange which comprises a base adapted to be connected to the shell, and a flange adapted to be connected to the second flange, characterized in that it comprises a protrusion which s' extends longitudinally from an integral upstream section of the outer skin of the ferrule, to a flared upstream section which delimits a radial space with the ferrule and which is adapted é to be fixed on the base of the second L-shaped flange by fixing
• the device according to the invention is of simple design and offers a reliable and costly solution for fixing a ferrule on a fan casing.
• the invention makes it possible not to alter and maintain the integrity of the acoustic structure of the ferrule formed by the outer skin, the inner skin and the acoustic panel of the ferrule.
• the protuberance has the shape of an annular ring which extends around the axis of the ferrule.
• the acoustic panel of the ferrule extends longitudinally continuously from upstream to downstream at least to the downstream portion of the protrusion.
• the ring and the second flange can each be made of a separate material which is chosen to best meet the mechanical stress and imposed weight requirements.
• the second flange is made of metallic material.
• the second flange is made of a plurality of independent parts which are arranged in a ring around the axis of the ferrule.
• the crown is made of composite material. This type of material offers a weight / strength compromise adapted to the mechanical stresses subjected to the crown.
• the ring has a wavy shape which draws an alternation of hollow and bumps distributed around the axis of the shell, said bumps each forming a radial extra thickness designed to promote the attachment of the second L-shaped flange.
• the acoustic panel extends longitudinally downstream beyond the plane of the second L-shaped flange.
• the design of the device according to the invention makes it possible not to perforate the acoustic panel by fixing means, thus preserving all the acoustic absorption performance of the panel.
• the device comprises a wedge which is interposed radially between the outer skin of the ferrule and the flared downstream portion of the crown.
• the fastening means comprise a plurality of metal links which connect the flared upstream portion of the ring to the base of the second L-shaped flange.
• the invention also relates to a method for manufacturing a device for fixing a downstream end of an air intake on a fan casing of an aircraft turbojet engine nacelle, according to any one of the preceding claims, characterized in that the protrusion is made integrally with the outer skin of the ferrule.
• FIG. 1 is a schematic view in longitudinal section, which illustrates an aircraft turbojet engine nacelle
• FIG. 2 is a schematic longitudinal sectional view, which illustrates a device for fixing the air intake ring on a fan casing of the nacelle of Figure 1, according to the invention
• FIG. 3 is a detail view broken away in perspective, which illustrates the first flange and the second flange of the device of FIG. 2;
• - Figure 4 is a detail view broken away in perspective, which illustrates the first flange and the second flange of the device of Figure 2 according to an alternative embodiment;
• FIG. 5 is a detail view with tear in perspective, which illustrates the connecting ring of the second flange on the ferrule of the device of Figure 2;
• FIG. 6 is a detailed cross-sectional view, which illustrates the connecting ring of the second flange on the ferrule of the device of Figure 2.
• upstream and downstream must be understood in relation to the flow of air flow inside the propulsion unit formed by the nacelle and the turbojet engine. , that is from left to right according to FIG.
• FIG. 1 shows a nacelle 10 of a turbojet engine 12 which has a tubular structure and which extends along a longitudinal axis A from upstream to downstream in the direction of flow of the airflow, from the left to the right according to Figure 1.
• the nacelle 10 comprises an air inlet 14 arranged upstream of the turbojet engine 12, a median section 16 intended to surround a fan 18 of the turbojet engine 12, a downstream section 20 intended to surround the combustion chamber of the turbojet engine 12 and possibly including means thrust reverser (not shown), and an ejection nozzle 22.
• the air inlet 14 comprises in particular an annular inlet lip 24 forming a leading edge, and a downstream tubular structure forming a ferrule 28 acoustics on which is reported the lip 24 for channeling the air towards the vanes of the blower 18.
• the acoustic ferrule 28 is extended longitudinally by a fan casing 30 to guide the flow of air.
• the ferrule 28 has an annular shape of axis A, which extends axially from upstream to downstream along the longitudinal axis A of the nacelle 10 and which is delimited radially by a skin internal 32 and an outer skin 34 which traps a cellular acoustic panel 70.
• the inner skin 32 is acoustically permeable and is for example constituted by a perforated skin allowing the sound waves to pass through it.
• the outer skin is waterproof and acoustically impermeable.
• the acoustic panel 70 is preferably a cellular material keeping the inner skin 32 and the outer skin 34 at a distance, the acoustic panel 70 forming a cavity designed to absorb and dampen the sound waves.
• the nacelle 10 is equipped with a device 36 for fixing the air inlet 14 on the fan casing 30, more particularly for fixing the acoustic shell 28 on the casing 30.
• the fixing device 36 comprises a first metal flange 38 which is fixed on an upstream end of the casing 30, and a second L-shaped metal flange 40 which is fixed on a downstream end of the ferrule 28.
• the first flange 38 has an annular base 42 extending generally axially along the longitudinal axis A of the nacelle 10 and which is fixed to the casing 30 by a mechanical connection means (not shown) as a set of screws. and nuts for example, or by any other means of attachment.
• first flange 38 has an annular collar 44 projecting radially outwardly from the base 42 and defining a first radial clamping face 46 arranged opposite the second flange 40.
• second flange 40 has an annular base 48 which extends generally axially along the longitudinal axis A of the nacelle 10 and an annular flange 50.
• the flange 50 of the second flange 40 projects radially outwardly from the associated base 48, the flange 50 delimiting a second radial flange face 52 intended to cooperate with the first flange face 46 complementary to the first flange 38.
• the second clamping face 52 and the first clamping face 46 are contiguous along a radial clamping plane P, and they each delimit a series of holes for the passage of fastening means, such as a set of screws and bolts. nuts 54 for example, or any other means of attachment.
• the second flange 40 is made of metal alloy, and preferably of aluminum alloy or titanium.
• alloys have high strengths and elongations before rupture which are particularly suitable for producing this type of flange which must withstand significant deformations imposed by the casing 30 in extreme cases of failure of a blade of the blower.
• the second flange 40 may be made of composites among discontinuous and continuous fiber thermocompression technologies, or RTM molding of fibrous textures.
• the fibers are preferably chosen from carbon fibers, glass fibers, and matrices from thermosetting epoxy polymers and thermoplastics from the Polyaryletherketone family.
• the flange 50 of the second flange 40 and the flange 44 of the first flange 38 can be machined.
• the second flange 40 is made of a plurality of sector-shaped portions 55 which are independent and identical and which are arranged in a ring around the axis of the ferrule 28.
• each part 55 delimits three holes which are uniformly distributed around the axis A and which are provided for the passage of the fastening means on the first flange 38.
• the second flange 40 is made in one piece in the form of a ring.
• the second flange 40 may be made of a plurality of parts which are mechanically interconnected by means of reported links.
• the device 36 comprises an annular crown protrusion 56 which extends around the axis A of the nacelle 10 and which extends longitudinally from an upstream section 58 integral with the outer skin 34 from the shell 28, to a downstream section 60 which is adapted to be fixed on the base 48 of the second L-shaped flange 40 by means of fasteners 61.
• the downstream section 60 of the ring 56 has a globally frustoconical flared shape of increasing radial section in an axial direction from upstream to downstream, this flared shape allowing the downstream section 60 to delimit a radial space 62, or cavity, with the outer skin 34 of ferrule 28.
• the ring 56 is made of composite material.
• the ring 56 is made of a succession of fabric skins which are pre-impregnated with a binder, such as resin.
• the ring 56 is made at the same time as the outer skin 34 of the collar 28, by a stack of layers of fabric and or fibers that can be part of the constitution of the outer skin 34.
• the layers of fabrics and / or fibers are impregnated with resin and solidified by polymerization.
• the skins of the crown 56 can be made by placing process pre-impregnated fibers of binder or draping pre-impregnated sheets of binder.
• the ring 56 can also be made by injection molding, for example by a resin injection process in a fiber preform arranged in a mold, this type of process is known by the acronym RTM for "resin transfer molding".
• the crown 56 can be glued or co-fired with the fiber layers of the outer skin 34 of the ferrule 28.
• the ring may be made by any other type of process for manufacturing a part made of composite material.
• an extractable tooling element (not shown) can be inserted for draping and polymerization of the assembly. .
• the downstream portion 60 of the ring 56 which is radially offset from the acoustic shell 28, has the advantage of not altering the geometric shape of the acoustic assembly formed by the outer skin 34, the inner skin 32 and the acoustic panel. 70 of the shell 28 which then extends axially continuously downstream continuously beyond the ring 56 and can extend up to the plane P of clamping, and possibly even beyond inside the fan casing 30.
• the device 36 comprises a wedge 64 of triangular section, shown in Figure 4, which is interposed radially between the outer skin 34 of the ferrule 28 and the downstream portion 60 flares from the ring 56 .
• the wedge 64 is for example made of composite material and in particular makes it possible to avoid or limit the deformation of the downstream section 60 of the ring 56, the wedge 64 possibly having the shape of a closed or open ring or formed of several angular sectors. .
• the fixing means 61 of the downstream section 60 of the ring 56 on the base 48 of the second flange 40 comprise a plurality of metal links, such as a set of screws and nuts and / or a set of rivets for example.
• the base 48 of the second flange 40 delimits a series of holes 65 for the passage of the fastening means 61.
• the holes 65 are distributed in two rows, staggered as shown in Figure 4 or vis-à-vis as shown in Figure 3.
• downstream portion 60 of the ring 56 can be machined if necessary to promote cooperation between the downstream section 60 of the ring 56 and the base 48 of the second flange 40 associated.
• downstream section 60 of the ring 56 has a shape corrugated which draws an alternation of hollow 66 and bumps 68 distributed around the axis A of the ferrule 28.
• the bumps 68 each form a radial excess thickness designed to promote the fixing of the ring 56 on the second flange 40 by the fastening means 61, as can be seen in FIG.
• the acoustic panel 70 extends longitudinally beyond the plane P of the second flange 40 in L.
• the acoustic panel 70 may extend only to the clamping plane P, the casing 30 then comprising an additional acoustic panel arranged in the extension.
• the fixing device 36 is lightweight, simple in design, robust and reliable, and it enables the ferrule 28 to be connected to the casing 30 without perforating the acoustic panel 70, thus preserving all its absorption capacities of the noise.
• the invention also relates to a method for manufacturing the device 36 described above.
• the protrusion 56 is made integrally with the outer skin 34 of the ferrule 28.
• the expression "made from material” means that the excrescence 56 is performed simultaneously with the outer skin 34 of the ferrule 28, as previously described.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Aviation & Aerospace Engineering (AREA)
• Structures Of Non-Positive Displacement Pumps (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=51987334

Family Applications (1)

Country Status (5)

Families Citing this family (13)

Family Cites Families (11)

• 2014
  • 2014-09-18 FR FR1458829A patent/FR3026134B1/fr active Active
• 2015
  • 2015-09-17 EP EP15788468.5A patent/EP3194749A1/de not_active Withdrawn
  • 2015-09-17 CN CN201580050534.8A patent/CN106715267A/zh active Pending
  • 2015-09-17 WO PCT/FR2015/052495 patent/WO2016042271A1/fr active Application Filing
• 2017
  • 2017-03-15 US US15/459,014 patent/US10415472B2/en not_active Expired - Fee Related

Non-Patent Citations (2)

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