Turbomachine propeller blade or blade made of composite material

Abstract

Turbomachine propeller blade or blade made of composite material The invention relates to a turbomachine propeller blade or blade (10), the propeller blade or blade comprising an aerodynamic profile structure (20) comprising at least one fiber reinforcement (200) and an insert (40) comprising a part (41) present in a housing arranged inside the fiber reinforcement, characterized in that the part (41) comprises on an external surface (51) at least one groove (43) extending around said part (41), said at least one groove comprising at least first and second bearing surfaces,said at least one first bearing surface having a first non-zero angle (α) relative to the longitudinal direction DL and said at least one second bearing surface having a second non-zero angle (β) relative to the longitudinal direction DL and in that the aerodynamic profile structure (20) comprises at least one excess thickness (44) present in said at least one groove (43) of the part (41) of the insert (40). Figure for the abstract: Fig 2.,

Description

Title of the invention: Turbomachine propeller blade or blade made of composite material Technical field

[0001] The present invention relates to the field of propeller blades or vanes made of composite material for aircraft such as those present on turbomachines. Prior art

[0002] In order to obtain lighter blades or vanes, it is known to make them from composite material, that is to say by making structural parts with fibrous reinforcement densified by a matrix.

[0003] Document US 2013 / 0017093 describes the production of a propeller blade from a fiber structure with an aerodynamic profile obtained by three-dimensional weaving and comprising an internal housing into which a part of a spar and several foam shaping elements are introduced. Before their introduction, the spar and the shaping elements are glued together in order to hold them together and facilitate their positioning in the fiber structure.

[0004] The presence of initially raw glue in the mold creates significant constraints on the manufacturing process, particularly at the injection cycle level. The presence of glue also increases the risks of manufacturing non-conformities. With this type of solution, the retention capacity of the aerodynamically profiled fiber structure with respect to the spar can be inhomogeneous on the final part.

[0005] Furthermore, the insertion of the spar assembly and the shaping elements into the fiber structure is carried out using an interposition film which makes it possible to avoid adhesion between the assembly and the dry fiber structure, in particular at the spar where the adhesive film is previously deposited. This film must be removed before the injection molding operation of the preform. When the film is removed, it may tear and leave pieces in the final part. Such contamination affects the health of the final part, which may be rejected in certain cases. The presence of this contamination may also reduce the retention capacity of the aerodynamically profiled fiber structure with respect to the spar.

[0006] It is therefore desirable to propose a solution for the production of propeller blades or vanes making it possible to improve the retention capacity of the aerodynamically profiled fibrous structure with respect to the insert as well as to reduce the risk of contamination during manufacturing. Statement of the invention

[0007] For this purpose, the invention proposes a turbomachine propeller blade or vane in composite material extending in a longitudinal direction and a transverse direction corresponding respectively to the span direction and the chord direction of the blade or propeller blade, the blade or propeller blade comprising an aerodynamic profile structure comprising at least one fibrous reinforcement obtained by three-dimensional weaving of threads and densified by a matrix and an insert comprising a part present in a housing provided inside the fibrous reinforcement, the part and the aerodynamic profile structure extending in the transverse direction between a leading edge and a trailing edge and in the longitudinal direction between a lower edge and a tip of the blade or propeller blade, characterized in that the part of the insert inside the fibrous reinforcement comprises on an external surface at least one groove extending around said part of the insert,said at least one groove comprising at least first and second bearing surfaces, said at least one first bearing surface having a first non-zero angle relative to the longitudinal direction and said at least one second bearing surface having a second non-zero angle relative to the longitudinal direction and in that the aerodynamic profile structure comprises at least one excess thickness present in said at least one groove of the part of the insert.

[0008] The invention proposes to improve the retention capacity of the aerodynamically profiled fibrous structure with respect to the insert by housing said at least one excess thickness in said at least one part of the insert. Contrary to what is provided in the prior art, no bonding step is included in the method of manufacturing the propeller blade or vane according to the invention. The use of a film is also not provided in the manufacturing method. It is therefore also possible, thanks to the invention, to minimize the risks of contamination of the final part and to simplify the manufacturing method thereof. In addition, because said at least one groove extends around the part of the insert, it is possible to ensure a homogeneous retention capacity according to the direction in which the groove extends.

[0009] According to a particular characteristic of the propeller blade or vane of the invention, said at least one groove may further comprise a third bearing surface, said third bearing surface has a third non-zero angle relative to the longitudinal direction and the excess thickness is held in place by support between the third bearing surface and at least one of the first and second bearing surfaces.

[0010] This makes it possible to introduce compressive forces that promote the retention of the excess thickness-groove interface and to promote the insertion of the excess thickness into the groove. Thanks to the presence of a third bearing surface, it is also possible to limit the opening of the preform when it is under load and therefore to minimize the risk of debonding occurring.

[0011] According to a particular characteristic of the propeller blade or vane of the invention, when the groove comprises a first span and a second span, the first non-zero angle a may be greater than or equal to 20° and less than or equal to 40° and the second non-zero angle [3 may be greater than or equal to 60° and less than or equal to 100°. It is thus possible to create a so-called "harpoon" effect which avoids any risk of the excess thickness coming out of said at least one groove and which makes it possible to optimize the retention on the excess thickness-groove interface.

[0012] According to a particular characteristic of the propeller blade or vane, the third span may intersect the second span by forming a fourth non-zero angle y less than 90°.

[0013] Such a value of the angle y makes it possible to improve the maintenance of the excess thickness in the groove when the blade or propeller blade is subjected to a centrifugal force.

[0014] According to a particular characteristic of the propeller blade or vane, the fourth non-zero angle y may be greater than or equal to 60° and less than 90°.

[0015] Such an angle makes it possible to further improve the maintenance of the excess thickness in the groove when the propeller blade or vane is subjected to centrifugal force.

[0016] According to a particular characteristic of the propeller blade or vane, the second non-zero angle [3 may be greater than 0° and less than or equal to 10°.

[0017] According to a particular characteristic of the propeller blade or vane, the value of the third non-zero angle 0 can be defined by the formula 0 = y + [3.

[0018] According to a particular characteristic of the propeller blade or vane, the number of grooves and excess thicknesses can each be equal to 3.

[0019] Such a number of grooves and extra thicknesses makes it possible to optimize the retention of the aerodynamically profiled fiber structure with respect to the insert.

[0020] The invention also provides a method for manufacturing a propeller blade or vane made of composite material extending in a longitudinal direction and a transverse direction corresponding respectively to the span direction and the chord direction of the propeller blade or vane to be manufactured, characterized in that the method comprises the following steps:

[0021] - the production of a fiber blank of an aerodynamic profile structure by three-dimensional weaving of threads, said blank comprising an internal housing,

[0022] - the introduction of a part of an insert into the internal housing of the blank fibrous so as to form a preform,

[0023] - holding the preform in a molding cavity of an injection tool having the shape of the propeller blade or vane to be manufactured, and

[0024] - injecting a precursor of a matrix into the molding cavity containing the preform and the transformation of the precursor into a matrix by heat treatment,

[0025] characterized in that the method further comprises, before the step of introducing the part of the insert into the internal housing of the fiber blank, the production of at least at least one groove on the external surface of said part of the insert extending around said part and, when producing the fiber blank, the formation of at least one protuberance on the internal or external surface of the fiber blank, and in that said protuberance is configured to allow the filling of said at least one groove of the part of the insert during the introduction step or during compaction of the preform carried out during the holding step.

[0026] No bonding step is included in the manufacturing process of the propeller blade or vane according to the invention, contrary to what is provided in the prior art. The use of a film is also not provided in the manufacturing process. It is therefore also possible thanks to the invention to minimize the risks of contamination of the final part and to simplify the manufacturing process thereof. The process also makes it possible to obtain a propeller blade or vane having a better capacity for retaining the aerodynamically profiled fiber structure with respect to the insert, and having a homogeneous retention capacity according to the direction in which the groove extends.

[0027] According to a particular characteristic of the method of the invention, the method makes it possible to obtain a propeller blade or vane described above.

[0028] According to a particular characteristic of the method of the invention, at least one protuberance can be formed on the external surface of the fibrous blank by projecting from a base portion thereof and said at least one base portion fills said at least one groove of the part of the insert during compaction.

[0029] According to a particular characteristic of the method of the invention, said at least one protuberance can be formed on the internal surface of the fiber blank and in which said at least one protuberance fills said at least one groove of the part of the insert during the introduction step Brief description of the drawings

[0030] Other characteristics and advantages of the present invention will emerge from the description given below, with reference to the appended drawings which illustrate exemplary embodiments thereof which are not in any limiting nature.

[0031] [Fig-1] [Fig.l] is a perspective view of a turbomachine blade in accordance with one embodiment of the invention,

[0032] [Fig.2] [Fig.2] is an exploded view showing the production of a preform of the dawn of [Fig.l],

[0033] [Fig.3] [Fig.3] is a partial sectional view of the part of the insert present in the housing of the fiber blank, in the longitudinal direction III-III of [Fig.2], showing said at least one groove in accordance with an embodiment of the invention,

[0034] [Fig.4] [Fig.4] is a partial sectional view of the part of the insert present in the housing of the fiber blank, according to the longitudinal direction III-III of [Fig.2], showing said at least one groove in accordance with another embodiment of the invention,

[0035] [Fig.5] [Fig.5] is an exploded perspective schematic view showing a injection tooling and the placement of the preform of [Fig.2] inside it,

[0036] [Fig.6a] [Fig.6a] is a partial sectional view of the fiber blank and the part of the insert in the internal housing thereof according to the longitudinal direction III-III of [Fig.2], showing the first stage of filling the groove of [Fig.3] with a first example of protuberance,

[0037] [Fig.6b] [Fig.6b] is a partial sectional view of the fiber blank and the part of the insert in the internal housing thereof according to the longitudinal direction III-III of [Fig.2], showing the second stage of filling the groove of [Fig.3] with the first example of protuberance,

[0038] [Fig.6c] [Fig.6c] is a partial sectional view of the fiber blank and the part of the insert in the internal housing thereof in the longitudinal direction of a blade according to an alternative embodiment, showing the first stage of filling the groove of [Fig.3] with a second example of protuberance,

[0039] [Fig.6d] [Fig.6d] is a partial sectional view of the fiber blank and of the part of the insert in the internal housing thereof in the longitudinal direction of a blade according to an alternative embodiment, showing the second step of filling the groove of [Fig.3] with the second example of protuberance.

[0040] [Fig.6e] [Fig.6e] is a partial sectional view of the fiber blank and the part of the insert in the internal housing thereof in the longitudinal direction of a blade according to another variant, showing the filling of the groove of [Fig.3] with a third example of protuberance,

[0041] [Fig.7] [Fig.7] is a schematic perspective view showing the tooling injection [Fig.5] closed during the matrix precursor injection step. Description of the embodiments

[0042] The invention applies generally to different types of propeller blades or vanes used in aircraft engines. The invention finds an advantageous but not exclusive application in large propeller blades or vanes which are intended to be integrated into pivoting or variable pitch systems. Such propeller blades or vanes are generally provided with a root having both a small footprint (compact shape) and good resistance to tensile, bending and circumferential compression forces. The vane according to the invention may in particular constitute a vane for streamlined mobile wheels such as fan blades or a blade for unducted moving wheels as in so-called “open rotor” aeronautical engines.

[0043] In the remainder of the description, an example of implementation of the method of the invention is described in relation to the manufacture of a blade for a non-ducted mobile wheel. However, the example embodiment also applies to the manufacture of other types of blade or propeller blade for a turbomachine for aircraft.

[0044] [Fig. 1] represents a blade 10 intended to be mounted on an aircraft turboprop, which extends in a longitudinal direction DL corresponding to the span direction, and in a transverse direction DT corresponding to the chord direction. The blade comprises, in a manner well known per se, an aerodynamic profile structure 20 intended to form the aerodynamic part of the blade, a root 33 formed by a part of greater thickness, for example with a bulb-shaped section, extended by a stilt 34. The aerodynamic profile structure extends in the transverse direction DT between a leading edge 20a and a trailing edge 20b and in the longitudinal direction between a lower edge 21a and a blade tip 21b. The aerodynamic profile structure 20 has in cross section a curved profile of variable thickness between its leading edge 20a and its trailing edge 20b.

[0045] The blade 10 comprises an insert, or spar, 40 which comprises a first part 31 extending outside the aerodynamic profile structure 20 and comprising the root 33 and Péchasse 34 and a second part 41 arranged inside the aerodynamic profile structure 20. At least one groove 43 is made on an external surface 51 of the part 41 of the insert. Said at least one groove 43 can be made by different techniques, such as for example by machining. The grooves 43 extend around the part 41 of the insert 40. This makes it possible to ensure a uniform retention capacity depending on the direction in which the grooves 43 extend. The grooves 43 can extend all around the part 41 (at 360°) or only over a fraction of the circumference thereof.In the latter case, two grooves can be made, symmetrically with respect to a plane containing the directions DL and DT, each located on a separate face of the part 4L. Alternatively, grooves can be arranged asymmetrically, with respect to the plane containing the directions DL and DT, on the faces of the part 4L.

[0046] According to a particular characteristic of the propeller blade or vane of the invention, the insert 40 may be made of a metallic material.

[0047] In the part 41 of the insert 40 two extra thicknesses 44 are present in the two grooves 43 as illustrated in [Fig.l]. The number of grooves 43 and the number of extra thicknesses 44 may each be greater than or equal to one.

[0048] According to a particular characteristic, the number of grooves 43 and the number of excess thicknesses 44 can each be greater than or equal to 2.

[0049] According to a particular characteristic, the number of grooves 43 and the number of excess thicknesses 44 can each be equal to 3.

[0050] The presence of the excess thicknesses 44 in the grooves 43 makes it possible to improve the retention capacity of the aerodynamically profiled fibrous structure with respect to the insert 40 while minimizing the risks of contamination thereof. In general, the grooves 43 may be partially or totally filled by the excess thicknesses 44. In particular, the excess thickness may fill at least 80% of the volume of each groove 43.

[0051] According to a particular characteristic, the grooves 43 and the extra thicknesses 44 may be present at a height between the first quarter and two thirds of the total height of the blade in the longitudinal direction DL. The positioning of the grooves 43 and the extra thicknesses 44 at such a height makes it possible to optimize the structural strength of the connection between the fiber blank 100 and the insert 40.

[0052] [Fig.2] shows an example of the production of a preform 200 of the blade. A fiber blank 100 is obtained by three-dimensional (3D) weaving.

[0053] The weaving may be carried out using a jacquard-type loom on which a bundle of warp threads or strands has been arranged in a plurality of layers, the warp threads being linked by weft threads. The weaving may be an "interlock" weave. By "interlock" we mean here a weaving weave in which each layer of weft threads links several layers of warp threads with all the threads of the same weft column having the same movement in the plane of the weave. In the invention, the roles of the warp and weft threads are interchangeable.

[0054] Other types of three-dimensional weaving may be used, such as those described in document WO 2006 / 136755.

[0055] For example, when weaving the fiber blank 100, two protrusions 440 may be woven at two locations 45 and 46 of the fiber blank 100 ([Fig.2]). The number of protrusions 440 may be greater than or equal to one. In this example, the protrusions 440 are woven onto an outer surface 55 of the fiber blank 100. The protrusions 440 protrude from a base portion 52 of the fiber blank 100. The two protrusions 440 each extend around the surface corresponding to the inner housing 104a of the fiber blank 100.

[0056] According to a particular characteristic of the invention, the protuberances 440 can be woven on the internal surface 54 of the fibrous blank 100. The protuberances 440 protrude from a base portion 52 of the fibrous blank 100.

[0057] In the embodiment illustrated in [Fig.2], the insert 40 comprises two grooves 43 at two locations 47 and 48 of the insert 40. The two locations 47 and 48 are aligned respectively with the locations 45 and 46 of the protuberances 440 when the insert 40 is introduced inside the blank 100.

[0058] Figures 3 and 4 illustrate a partial sectional view of the part 41 of the insert 40, along the longitudinal direction III-III in [Fig.2] for two examples of embodiment of grooves 43.

[0059] In the example in [Fig. 3], the grooves 43 comprise at least a first bearing surface 59 and a second bearing surface 60. The bearing surfaces 59, 60 each respectively have a non-zero angle α and β relative to the longitudinal direction DL.

[0060] According to a particular characteristic of the invention, when the groove 43 comprises a first bearing surface and a second bearing surface, the first non-zero angle α may be greater than or equal to 20° and less than or equal to 40° and the second non-zero angle α may be greater than or equal to 60° and less than or equal to 100°.

[0061] This makes it possible to create a so-called “harpoon” effect which prevents the excess thickness from coming out of said at least one groove.

[0062] According to a particular characteristic of the invention, the grooves 43 may comprise a third bearing surface 61 as illustrated in [Fig. 4]. Said third bearing surface has a third non-zero angle θ relative to the longitudinal direction DL. The third bearing surface 61 is distinct from the first 59 and second 60 bearing surfaces. In the example illustrated, the third bearing surface 61 intersects the second bearing surface 60, forming a fourth non-zero angle θ less than 90° with the latter. According to a particular characteristic, the fourth non-zero angle θ may be greater than or equal to 60° and less than 90°. When the groove comprises a third bearing surface 61, the second non-zero angle θ may be greater than 0° and less than or equal to 10°.

[0063] Such a value of the angle y makes it possible to improve the maintenance of the excess thickness in the groove when the blade or propeller blade is subjected to a centrifugal force.

[0064] Such values ​​for the first non-zero angle α, for the second non-zero angle β and for the third non-zero angle θ make it possible to further limit the opening of the preform when it is under load while avoiding over-compaction of the excess thickness in the groove during the manufacture of the blade or propeller blade.

[0065] The presence of this third bearing surface 61 makes it possible to introduce compressive forces promoting the retention of the excess thickness-groove interface, to promote the insertion of the excess thickness into the groove and to limit manufacturing defects. Thanks to this characteristic, it is also possible to limit the opening of the preform when it is under load and therefore to minimize the risk of the appearance of debonding.

[0066] According to a particular characteristic of the invention, the third non-zero angle 0 can be defined by the following formula: 0 = y + [3.

[0067] Figures 3 and 4 show grooves 43 having the same shape and size, but it does not go beyond the scope of the invention if this is not the case if there are several grooves. In the latter case, the blank is adapted to the structure of the grooves considered.

[0068] Then, the shaping of the dry fibrous blank 100 is carried out by introducing into the internal housing 104a a part 41 of the insert 40. The two locations 47 and 48 are aligned respectively with the locations 45 and 46 ([Fig.5]).

[0069] When the protrusions 440 are formed on the internal surface 54 of the fiber blank 100, the protrusions 440 at least partially fill the grooves 43 at the time of introduction of the part 41 into the internal housing 104a (figures 6c and 6e).

[0070] In the context of the example of [Fig. 5], the grooves 43 comprise a first and a second bearing surface (59, 60) and the protrusions 440 have been produced on the external surface 55 of the fiber blank. These protrusions 440 project from a base portion 52 of the fiber blank (see also [Fig. 6a]).

[0071] As illustrated in [Fig.5], the blade preform 200 is placed in an injection tool 300 which comprises a first shell 310 comprising in its center a first imprint 311 corresponding in part to the shape and dimensions of the blade to be produced and a second shell 320 comprising in its center a second imprint 321 corresponding in part to the shape and dimensions of the blade to be produced.

[0072] Once the tool 300 is closed as illustrated in [Fig.7], the first and second impressions 311 and 321 respectively of the first and second shells 310 and 320 together define a molding cavity 301 having the shape of the blade or propeller blade to be produced and in which the preform 200 is held.

[0073] A compaction can be carried out during the step of holding the preform in the molding cavity. In the case of the example of FIGS. 6a and 6b, the filling of said at least one groove 43 is carried out during the compaction of the preform because the protuberances 440 have been formed on the outer surface 55 of the fiber blank 100. Before the compaction, the protuberances 440 are located on the side opposite the grooves 43.

[0074] During the first step of the compaction process, a compaction force is applied to the first and second shells 310 and 320 respectively to bring the shells 310 and 320 closer to each other until a portion of the blank, located at the protuberances 440, deforms and penetrates into the grooves 43. More precisely during compaction, the base portions 52 deform so as to be introduced into the grooves 43. This gives the aerodynamic profile structure 20 which comprises an excess thickness 44 present in each of the grooves 43.

[0075] According to a particular characteristic of the invention, the filling of the grooves 43 is carried out during the introduction of the part 41 of the insert 40 into the internal housing. 104a of the fiber blank. This is the case when the protrusions 440 are made on the internal surface 54 of the fiber blank 100. In this case, the protrusions 440 are intended to form the excess thicknesses 44 present in the grooves 43. Examples of two corresponding embodiments are shown in FIGS. 6c to 6e.

[0076] In the case of the example illustrated in [Fig.6c], when introducing the part 41 of the insert 40 into the fiber blank 100, the grooves 43 are partially filled by the protrusions 440. Then, a compaction force is applied until the protrusions 440 further fill the space formed by the grooves 43 ([Fig.6d]). In the examples illustrated in FIGS. 6a to 6d, the protrusions 440 deform under the effect of the compaction force applied to the first and second shells 310 and 320 respectively.

[0077] According to a particular characteristic of the invention, when the part 41 of the insert 40 is introduced into the fiber blank 100, the grooves 43 are filled by the protrusions 440 ([Fig.6e]). In this case, no compaction force is necessary to ensure filling. In this case, the protrusions 440 have, before introduction, the same shape and the same dimensions as the grooves 43.

[0078] Thus, the manufacture of the propeller blade or vane of the invention does not require any adhesive film on the external surface 51 of the part 41 of the insert 40, which greatly simplifies the manufacturing process because it is no longer necessary to protect the insert when it is introduced into the blank 100. The absence of the use of adhesive also simplifies the manufacturing process during the injection step.

[0079] The fibrous part of the preform, here the shaped fibrous blank, is then densified, as illustrated in [Fig.7]. The densification of the fibrous part of the preform consists of filling its porosity with the material constituting the matrix. This densification is carried out in a manner known per se using a liquid process. The liquid process consists of impregnating the preform with a liquid composition containing a precursor of the matrix material. The precursor is usually in the form of a polymer, such as a high-performance epoxy resin, possibly diluted in a solvent.

[0080] The transformation of the precursor into a matrix, namely its polymerization, is carried out by heat treatment, generally by heating the injection tooling, after elimination of any solvent and crosslinking of the polymer, the preform still being maintained in the molding cavity having a shape corresponding to that of the part to be produced. In the example described here, the injection tooling 300 further comprises a lower part 340 and an upper part 350 between which the first and second shells 310 and 320 are placed. The lower part 340 and the upper part 350 may be equipped with heating means (not shown in the [Fig.7]).

[0081] According to one aspect of the invention, the densification of the fiber preform can be carried out by the well-known transfer molding process known as RTM ("Resin Transfer Molding"). According to the RTM process, the fiber preform is placed in a mold having the external shape of the part to be produced. A thermosetting resin is injected into the internal space of the mold which includes the fiber preform. A pressure gradient is generally established in this internal space between the place where the resin is injected and the orifices for discharging the latter in order to control and optimize the impregnation of the preform by the resin.

[0082] According to a particular characteristic of the invention, the precursor of the matrix injected into the preform is an epoxy resin forming an organic matrix after polymerization.

[0083] As illustrated in [Fig.7] and in accordance with the RTM method, a resin 380, for example a thermosetting resin, is injected via the injection port 313 of the first shell 310 into the molding cavity 301 occupied by the preform 200. Before the injection of the resin 380, the molding cavity 301 is placed under vacuum, for example via the port 323 of the second shell 320 which is connected to a vacuum draw conduit (not shown in [Fig.7]). This configuration allows the establishment of a pressure gradient between the lower part of the preform 200 where the resin is injected and the upper part of the preform located near the port 323. In this way, the resin 380 injected substantially at the level of the lower part of the preform will progressively impregnate the entire fibrous part of the preform by circulating in it up to the evacuation port 323 through which the surplus is evacuated.Of course, the first and second shells 310 and 320 of the tooling 300 may respectively comprise several injection ports and several evacuation ports.

[0084] The resin used may be, for example, an epoxy resin with a temperature class of 180°C (maximum temperature supported without loss of characteristics). Resins suitable for RTM processes are well known. They preferably have a low viscosity to facilitate their injection into the fibers. The choice of temperature class and / or the chemical nature of the resin is determined according to the thermomechanical stresses to which the part must be subjected. Once the resin has been injected throughout the reinforcement, it is polymerized by heat treatment in accordance with the RTM process.

[0085] The injection of the resin into the fiber preform and its transformation into a matrix allows both the densification or the consolidation of the blade preform comprising the dry fiber blank 100 and the grooves 43 filled by the excess thicknesses 44 of said fiber blank 100.

[0086] After injection and polymerization, the blade is demolded. Finally, the blade can be trimmed to remove excess resin and the chamfers are machined. No further machining is necessary since, the part being molded, it respects the required dimensions. We then obtain the blade 10 of [Fig.l] in composite material comprising a fiber reinforcement corresponding to the fiber blank 100 densified by the matrix.

Claims

Claims

1. Turbomachine propeller blade or vane (10) made of composite material extending in a longitudinal direction (DL) and a transverse direction (DT) corresponding respectively to the span direction and the chord direction of the propeller blade or vane, the propeller blade or vane comprising an aerodynamic profile structure (20) comprising at least one fiber reinforcement obtained by three-dimensional weaving of threads and densified by a matrix and an insert (40) comprising a part (41) present in a housing arranged inside the fiber reinforcement, the part (41) and the aerodynamic profile structure (20) extending in the transverse direction DT between a leading edge (20a) and a trailing edge (20b) and in the longitudinal direction Dl between a lower edge (21a) and a tip (21b) of the propeller blade or vane,characterized in that the part (41) comprises on an external surface (51) at least one groove (43) extending around said part (41), said at least one groove comprising at least first and second bearing surfaces (59, 60), said at least one first bearing surface (59) having a first non-zero angle (a) relative to the longitudinal direction DL and said at least one second bearing surface (60) having a second non-zero angle (|3) relative to the longitudinal direction Dl and in that the aerodynamic profile structure (20) comprises at least one excess thickness (44) present in said at least one groove (43) of the part (41) of the insert (40).,

2. Turbomachine propeller blade or vane (10) according to claim 1, in which said at least one groove (43) further comprises a third bearing surface (61), said third bearing surface (61) having a third non-zero angle (0) relative to the longitudinal direction DL and the excess thickness being held in place by support between the third bearing surface and at least one of the first and second bearing surfaces (59, 60).

3. A turbomachine propeller blade or vane (10) according to claim 1, wherein the first non-zero angle (a) is greater than or equal to 20° and less than or equal to 40° and the second non-zero angle (|3) is greater than or equal to 60° and less than or equal to 100°.

4. Turbomachine propeller blade or vane (10) according to claim 2, wherein said third span 61 intersects the second span 60 forming a fourth non-zero angle (y) less than 90°.

5. Turbomachine propeller blade or vane (10) according to claim 4, in which the fourth non-zero angle (y) is greater than or equal to 60° and less than 90°.

6. A turbomachine propeller blade or vane (10) according to any one of claims 4 or 5, wherein the second non-zero angle (|3) is greater than 0° and less than or equal to 10°.

7. A turbomachine propeller blade or vane (10) according to any one of claims 4 to 6, wherein the value of the third non-zero angle (0) is defined by the formula 0 = y + [3.

8. Turbomachine propeller blade or vane (10) according to any one of claims 1 to 7, in which the number of grooves (43) and of excess thicknesses (44) are each equal to 3.

9. Method for manufacturing a propeller blade or blade made of composite material extending in a longitudinal direction (DL) and a transverse direction (DT) corresponding respectively to the span direction and the chord direction of the propeller blade or blade to be manufactured, characterized in that the method comprises the following steps: - producing a fiber blank (100) of an aerodynamic profile structure (20) by three-dimensional weaving of threads, said blank (100) comprising an internal housing (104a), - introducing a part (41) of an insert (40) into the internal housing (104a) of the fiber blank so as to form a preform (200), - holding the preform (200) in a molding cavity (301) of an injection tool (300) having the shape of the propeller blade or blade (10) to be manufactured,and - injecting a precursor of a matrix into the molding cavity (301) containing the preform (200) and transforming the precursor into a matrix by heat treatment, characterized in that the method further comprises, before the step of introducing the part (41) of the insert (40) into the internal housing (104a) of the fiber blank (100), producing at least one groove (43) on the external surface of the part (41) of the insert (40) extending around said part (41) and, during the production of the fiber blank (100), forming at least one protuberance (440) on the internal (54) or external (55) surface of the fiber blank (100), and in that said protuberance (440) is configured to allow the filling of said at least one groove of the part (41) of the insert (40) during the introduction step or during compaction of the preform produced, during the holding stage.

10. The method of claim 9, wherein at least one protrusion (440) is formed on the outer surface (55) of said fibrous blank (100) projecting from a base portion (52) thereof and wherein said base portion (52) fills said at least one groove of the part (41) of the insert (40) upon compaction.

11. The method of claim 9, wherein at least one protrusion (440) is formed on the inner surface (54) of said fibrous blank (100) and wherein said protrusion (440) fills said at least one groove of the portion (41) of the insert (40) during the introduction step.

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