• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    The invention relates to an attached platform (1) intended to be positioned between two neighboring blades of an aerospace turbomachine fan, said platform comprising a vein wall (10) of composite material comprising a central portion (16), and a first and a second edge (18) extending in a longitudinal direction of said wall, each edge extending a predetermined distance (D) from the central portion (16) in a transverse direction of said wall, said vein wall comprising a fiber reinforcement densified by a matrix, characterized in that the fibrous reinforcement present in the central portion (16) has a three-dimensional weave, and in that the fibrous reinforcement present in the first and second edges (18) has at least partly a two-dimensional weave. The invention also relates to a fan module, a turbomachine and a method of manufacturing such a platform.
    公开号:FR3053724A1
    申请号:FR1755813
    申请日:2017-06-26
    公开日:2018-01-12
    发明作者:Jeremy GUIVARC'H；Francois Charleux
    申请人:Safran Aircraft Engines SAS；
    IPC主号:
    专利说明:

    © Publication number: 3,053,724 (to be used only for reproduction orders) (© National registration number: 17 55813 ® FRENCH REPUBLIC
    NATIONAL INSTITUTE OF INDUSTRIAL PROPERTY
    COURBEVOIE © IntCI 8
    F 01 D 5/28 (2017.01), B 29 B 11/16
    A1 PATENT APPLICATION
    ©) Date of filing: 26.06.17. © Applicant (s): SAFRAN AIRCRAFT ENGINES (30) Priority: 05.07.16 US 15201979. Simplified joint stock company - FR. @ Inventor (s): GUIVARC'H JEREMY and CHARLEUX FRANÇOIS. (43) Date of public availability of the request: 12.01.18 Bulletin 18/02. (© List of documents cited in the report of preliminary research: The latter was not established on the date of publication of the request. (© References to other national documents @ Holder (s): SAFRAN AIRCRAFT ENGINES Company related: by simplified actions. ©) Extension request (s): © Agent (s): CABINET BEAU DE LOMENIE.
    OF TURBOMACHINE, AND METHOD FOR THE
    FR 3 053 724 - A1 (t> 4) ADDED PLATFORM FOR BLOWER MANUFACTURING.
    (© The invention relates to an attached platform (1) intended to be positioned between two adjacent blades of an aeronautical turbomachine fan, said platform comprising a vein wall (10) made of composite material comprising a central portion (16), and first and second edges (18) extending in a longitudinal direction of said wall, each edge extending a determined distance (D) from the central portion (16) in a transverse direction of said wall, said wall vein comprising a fibrous reinforcement densified by a matrix, characterized in that the fibrous reinforcement present in the central portion (16) has a three-dimensional weaving, and in that the fibrous reinforcement present in the first and second edges (18) has at least partly a two-dimensional weaving The invention also relates to a blower module, a turbomachine and a method of manufacturing such a platform.

    Invention background
    The present invention relates to the general field of aeronautical turbomachines, and more particularly relates to an attached platform for a turbomachine fan.
    The fan of an aeronautical turbomachine generally comprises a plurality of movable blades between which are present, at their foot, platforms. The main function of the platforms is to delimit the flow stream of the gas flow entering the turbomachine. Due to their aerodynamic function, the vein walls of the platforms must be in intimate contact with the neighboring blades to ensure a seal between the platforms and the blades. When ingesting objects (ice blocks, birds, etc.), the fan blades may be impacted and deform. The deformations are then transmitted to the vein walls of the platforms which must as far as possible not be damaged or break, even in the event of impact is important.
    To avoid damage to the blades and platforms, the contact between the blades and the upper walls of the platforms must be adapted. To do this, it is known to thin the edges of the upper wall of platforms which are intended to be in contact with the blades, that is to say to reduce the thickness locally at the level of the blade contact zones. /platform. These thinner edges make it possible to obtain a more flexible contact between the platforms and the blades, and to effectively absorb shocks to reduce the damage caused to the blades and the platforms.
    When the platforms are made of composite material produced from a fibrous reinforcement densified by a matrix, the thinning of the edges of the vein wall generally requires a machining step. In particular, with thinned edges, it is often necessary to install seals to seal between the blades and the platforms. The delicate machining stage lengthens the manufacturing and assembly processes of the platforms, and increases their costs.
    There is therefore a need for an added fan blade platform which is easy and inexpensive to manufacture, and which does not have the aforementioned drawbacks.
    Subject and summary of the invention
    The main object of the present invention therefore is to overcome such drawbacks by proposing an attached platform intended to be positioned between two adjacent blades of an aeronautical turbomachine fan, said platform comprising a wall of a composite material vein comprising a central portion, and first and second edges extending in a longitudinal direction of said wall, each edge extending a determined distance from the central portion in a transverse direction of said wall, said vein wall comprising a fibrous reinforcement densified by a matrix , characterized in that the fibrous reinforcement present in the central portion has a three-dimensional weaving, and in that the fibrous reinforcement present in the first and second edges has at least partially a two-dimensional weaving.
    The term “two-dimensional weaving” or “2D weaving” is understood here to mean a conventional weaving mode by which each warp thread passes from one side to the other of threads of a single weft layer. The term “three-dimensional weaving” or “3D weaving” is understood here to mean a mode of weaving by which at least some of the warp threads link weft threads on several layers of weft.
    The edges of the vein wall of the platform according to the invention make it possible to ensure flexible contact between the platform and the neighboring blades, without requiring additional machining, and can make it possible to avoid adding a seal. Indeed, at constant thickness, a composite material having a fibrous reinforcement obtained by three-dimensional weaving needs more energy to delaminate than a composite material having a fibrous reinforcement obtained by two-dimensional weaving. It is thus possible to increase the flexibility of the composite material at the edges by providing, from the weaving of the fibrous reinforcement, a different weave between the edges (at least partially woven 2D) and the central portion of the vein wall ( 3D woven). It is then no longer necessary to machine the edges to obtain a platform capable of withstanding collisions with neighboring blades during impacts with objects.
    The weaving weave of the first and second edges can be chosen from: canvas, satin, twill.
    Each edge can extend in the transverse direction of the vein wall from the central portion over a determined distance D such that a ratio D / L is between 2% and 10%, for example between 5% and 10%, where L is the width of the vein wall in the transverse direction of said wall.
    Each edge may have a thickness e such that an e / D ratio is between 5% and 50%, for example between 5% and 10%, where D is the determined distance over which each edge extends in the transverse direction of the vein wall from the central portion.
    In an exemplary embodiment, the platform may include a bottom wall intended to rest on a fan disk and two side walls extending between the bottom wall and the vein wall of said platform. In this configuration, the platform is commonly called a "boxed" platform.
    In an exemplary embodiment, the platform can be made of composite material and comprise a fibrous reinforcement densified by a matrix, the fibrous reinforcement of the vein wall constituting a part of the fibrous reinforcement of the platform.
    The invention also relates to an aeronautical turbomachine blower module comprising at least two blades and at least one platform such as that presented above positioned between two adjacent blades, and also relates to a turbomachine comprising such a blower module. By fan module is meant, in a manner known per se, the module of the turbomachine which in particular comprises the fan and, where appropriate, the low pressure compressor.
    Finally, the invention also relates to a method for manufacturing an attached platform such as that presented above, the method comprising the following steps:
    the weaving of a fibrous preform intended to form the fibrous reinforcement of the vein wall of the platform, and
    - The formation of a matrix in the porosity of said fibrous preform.
    Brief description of the drawings
    Other characteristics and advantages of the present invention will emerge from the description given below, with reference to the accompanying drawings which illustrate exemplary embodiments thereof without any limiting character. In the figures:
    FIG. 1 shows an attached platform for a box-type turbomachine fan,
    FIG. 2 is a diagrammatic view in cross section of the added platform of FIG. 1, and
    - Figures 3A and 3B, and 4A and 4B, respectively illustrate two examples of weaving weaves at an edge of the vein wall.
    Detailed description of the invention
    FIG. 1 shows an example of an attached platform 1 of an aeronautical turbomachine fan. The platform 1 is positioned between two neighboring blades 2 (only one blade 2 is shown diagrammatically in dotted lines in FIG. 1) and mounted on a fan disk 3. The platform 1 illustrated in FIG. 1 is a platform entirely of composite material and of the box type, that is to say having a vein wall 10, a bottom wall 12 and two side walls 14 which extend between the bottom wall 12 and the vein wall
    10. The bottom wall 12 of the platform is, when the engine is stopped, in contact with the fan disc 3. The direction of the air flow entering the turbomachine is indicated in the figure by the arrow F. When the engine is in operation, the vein wall 10 of the platform delimits inside (with respect to the longitudinal axis of the turbomachine, not shown) the flow stream for the gas flow entering the turbomachine.
    The platform 1 may include all or part of a fibrous reinforcement densified by a matrix. The fibrous reinforcement may include carbon fibers, or ceramic fibers. The matrix can in turn be a ceramic or, more often, organic matrix, and obtained for example from a densification resin.
    FIG. 2 shows a schematic view of a section of the platform 1 of FIG. 1. The vein wall 10 of the platform 1 comprises a central portion 16 and two edges 18. The edges 18 extend in the longitudinal direction of the vein wall 10, here over the entire length of the vein wall 10. The longitudinal direction of the vein wall 10 means the direction given by its largest dimension, the transverse direction being perpendicular to the longitudinal direction. The vein wall 10 here extends transversely between its two edges 18.
    According to the invention, the vein wall 10 comprises a fibrous reinforcement densified by a matrix. The fibrous reinforcement has, in a part corresponding to the central portion 16, a three-dimensional weaving. The parts of the fibrous reinforcement corresponding to the edges 18 of the wall of the vein 10 have at least in part a two-dimensional weaving. The fibrous reinforcement may for example have in the central portion 16 a weave of the interlock or multi-layer type, and in the edges a weave of the satin, canvas or twill type. It will be noted that it is also possible to provide a mixed weaving in the fibrous reinforcement of the edges 18, that is to say two-dimensional over part of the thickness of the edge 18, and three-dimensional over another part of the thickness edge 18.
    Each of the edges 18 can extend in the transverse direction of the vein wall 18 from the central portion 16 over a determined distance D. The distance D at a point of the vein wall 10 can be such that D / L is understood between 2% and 10%, for example between 5% and 10%, where L is the width of the vein wall at the point considered. Of course, as for the platform 1 in FIG. 1, the width L can vary along the wall of the vein 10, so that the distance D can also be variable along the wall of the vein 10. The thickness e of an edge 18 may be different from the thickness of the rest of the vein wall
    10. In this case, the thickness e of an edge 18 can be such that e / D is between 5% and 50%, for example between 5% and 10%.
    Two examples of weaving weaves in the area A of the edges 18 identified in FIG. 2 will be described respectively in connection with FIGS. 3A and 3B, and 4A and 4B. In these figures, the weft threads are visible in section and shown in staggered rows, so that a layer of weft thread T comprises two half-layers of consecutive weft threads ti and t 2 , t 3 and U, etc. The warp threads are referenced Ci to Cio- Throughout the text and in all the drawings, it is mentioned and represented, by convention and for the sake of convenience, that it is the warp threads which are deviated from their path to grip the threads weft of a weft layer or of several weft layers. However, a reversal of roles between warp and weft is possible.
    FIGS. 3A and 3B respectively show two planes of weaving weave of the fibrous reinforcement in zone A near an edge 18, according to a first example. In this example, the fibrous reinforcement of the entire central portion 16 has a three-dimensional weaving weave of the interlock type, and that of the edges 18 has a two-dimensional weaving weave of the twill type. Eleven layers of weft threads T of the fibrous reinforcement of the central portion 16 have been shown, or twenty-two half-layers of weft threads ti to t 2 2. The fibrous reinforcement at the edge 18 comprises ten layers of threads of weft T, i.e. twenty half-layers of weft yarns ti to t 2 o In the example illustrated, the fibrous reinforcement has, at the level of the central portion 16, an interlock weave weaving in which each warp yarn c x to Cio binds three half layers of weft yarn. Then, at the edge 18, the fibrous reinforcement has a weave with conventional twill weave where each warp thread Ci à Cio grasps two weft threads passing on one side and the other with a single layer of weft T. At the edges 18, the layers of weft threads T are not linked to each other by warp threads Ci to Ci 0 . Thus, one obtains in the edges 18 a superposition of two-dimensional fabric strips which are each connected to the central portion 16 by weaving. In the event of an impact inducing relative displacements of the edges 18 of the platform 1 against the neighboring vanes 2, delamination may occur between the layers or strips of fabrics having a two-dimensional weaving, that is to say that these strips of fabrics will be able to separate from each other.
    FIGS. 4A and 4B respectively show two planes of weaving weave of the fibrous reinforcement in zone A near an edge 18, according to a second example. In this example, the fibrous reinforcement of the entire central portion 16 has an interlock weaving weave, and that of the edges 18 has a mixed weaving weave with two portions 20 and 22 in the thickness of the edge 18 having a twill weaving weave (two-dimensional), and a portion 24 in the thickness of the edge 18 having an interlock weaving weave (three-dimensional).
    As in the first example, the fibrous reinforcement has, at the central portion 16, an interlock weave weave in which each warp thread Ci to Cio links three half-layers of weft thread. Then, at the interface between the central portion 16 and the edge 18, the first two Ci and C2, and the last two Cg and Cio warp threads of the edge 18 follow a twill pattern where each warp thread comes to grip two threads of weft, and in which each warp thread binds a single layer of weft threads T. The remaining warp threads C3 to c 8 continue their path without changing the pattern in the fibrous reinforcement of edge 18, by binding three half-layers of weft threads between them in an interlock weave. In portion 24 the layers of weft threads T are linked together by the threads c 3 to c 8 . In the edges 18, the first two and the last two layers of weft threads T are not linked to each other, nor to those of the portion 24. By using the weaving weave exemplified here, the edges 18 have only partly a two-dimensional weaving in the portions 20 and 22. Thus, in this example, the edges 18 each have two bands of two-dimensional fabrics in each portion 20 and 22; and a strip having a three-dimensional weaving in the portion 24. The aforementioned strips of the portions 20, 22 and 24 are all connected to the central portion 16 of the wall of the vein 10 by weaving.
    To manufacture a platform 1 according to the invention, it is first of all possible to obtain by weaving a fibrous preform intended to form the fibrous reinforcement of the platform. A box platform 1 such as that illustrated in FIG. 1 can be obtained from a single fibrous preform. Alternatively, several fiber preforms can be used which will then be assembled before densification, for example a fiber preform for the vein wall 10 and a fiber preform for the rest of the platform. The fibrous preform of the vein wall 10 is woven by respecting the weaving characteristics described above, and by using for example the weaves described previously at the edges 18. Of course, other weaving weaves than those presented above can be used without departing from the scope of the invention.
    Finally, a matrix can be formed by any known method inside the fibrous preform of the platform 1, optionally shaped. For example, the platform 10 can be manufactured by resin injection molding in the fiber preform. This process is known in English under the abbreviation RTM for "Resin Transfer Molding". For this, there is an injection mold having the shape of the platform 1 in which the dry fibrous preform is positioned, then a resin is injected under pressure inside the mold, the resin is solidified so as to form a matrix in the porosity of the fibrous preform, and the platform 1 thus produced is extracted from the mold.
    权利要求:
    Claims (9)
    [1" id="c-fr-0001]
    1. Reported platform (1) intended to be positioned between two blades (2) adjacent to an aeronautical turbomachine blower, said platform comprising a vein wall (10) of composite material comprising a central portion (16), and a first and a second edge (18) extending in a longitudinal direction of said wall, each edge extending over a determined distance (D) from the central portion (16) in a transverse direction of said wall, said vein wall comprising a fibrous reinforcement densified by a matrix, characterized in that the fibrous reinforcement present in the central portion (16) has a three-dimensional weaving, and in that the fibrous reinforcement present in the first and second edges (18) has at least partially two-dimensional weaving.
    [2" id="c-fr-0002]
    2. Platform according to claim 1, characterized in that the weaving weave of the first and second edges (18) is chosen from: canvas, satin, twill.
    [3" id="c-fr-0003]
    3. Platform according to any one of claims 1 and 2, characterized in that each edge (18) extends in the transverse direction of the vein wall (10) from the central portion (16) over a determined distance D such that a D / L ratio is between 2% and 10%, where L is the width of the vein wall in the transverse direction of said wall.
    [4" id="c-fr-0004]
    4. Platform according to any one of claims 1 to 3, characterized in that each edge (18) has a thickness e such that an e / D ratio is between 5% and 50%, where D is the determined distance on which each edge extends in the transverse direction of the vein wall (10) from the central portion (16).
    [5" id="c-fr-0005]
    5. Platform according to any one of claims 1 to 4, characterized in that it comprises a bottom wall (12) intended to rest on a blower disc (3) and two side walls (14) extending between the bottom wall and the vein wall (10) of said platform.
    [6" id="c-fr-0006]
    6. Platform according to any one of claims 1 to 5, 5 characterized in that it is made of composite material and comprises a fibrous reinforcement densified by a matrix, the fibrous reinforcement of the vein wall (10) constituting a part of the fibrous reinforcement of the platform.
    [7" id="c-fr-0007]
    7. Aeronautical turbomachine fan module 10 comprising at least two blades (2) and at least one platform (1) according to any one of claims 1 to 6 positioned between two neighboring blades.
    [8" id="c-fr-0008]
    8. Aeronautical turbomachine comprising a fan module according to claim 7.
    [9" id="c-fr-0009]
    9. A method of manufacturing an attached platform (1) according to any one of claims 1 to 6, the method comprising the following steps:
    20 - weaving a fibrous preform intended to form the fibrous reinforcement of the vein wall (10) of the platform, and
    - The formation of a matrix in the porosity of said fibrous preform.
    1/3
    2/3
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    法律状态:
    2018-05-22| PLFP| Fee payment|Year of fee payment: 2 |
    2018-06-29| PLSC| Search report ready|Effective date: 20180629 |
    2020-05-20| PLFP| Fee payment|Year of fee payment: 4 |
    2021-05-19| PLFP| Fee payment|Year of fee payment: 5 |
    优先权:
    申请号 | 申请日 | 专利标题
    US15201979|2016-07-05|
    US15/201,979|US10436036B2|2016-07-05|2016-07-05|Fitted platform for a turbine engine fan, and a method of fabricating it|
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