METHOD FOR MANUFACTURING A BLADE FOR AN AIRCRAFT TURBOMACHINE AND ASSOCIATED BLADE

Abstract

The invention relates to a method for manufacturing a blade (20) comprising the following steps: (a) providing a blade (21), having an axis of elongation (Z) and comprising a leading edge (23) and a trailing edge (24) connected by an intrados face (25b) and an extrados face (25a) opposite the intrados face (25b), (b) providing a protective shield (26), (c) disposing of a layer of adhesive (27) on an external surface of the blade (21) or on an internal surface of the protective shield (26), (d) assembling the metallic protective shield (26) onto the blade (21), the leading edge (23) being covered by the protective shield (26), characterized in that the method further comprises the following step: (e) inserting an insert (28) into the layer of adhesive (27), the insert (28) having an internal cavity (28a) and extending along the axis elongation (Z) parallel to the leading edge (23). Abbreviated figure: Figure 3a

Description

Title of the invention: METHOD FOR MANUFACTURING A BLADE FOR AN AIRCRAFT TURBOMACHINE AND BLADE PARTNER Technical field of the invention

[0001] The invention relates to the technical field of blades for aircraft turbomachines.

[0002] The invention relates more particularly to the field of manufacturing fan blades comprising a blade made of composite material, for aircraft turbomachines. Technical background

[0003] In a well-known manner, an aircraft turbomachine extends along a longitudinal axis and comprises, from upstream to downstream, in the direction of gas flow, a fan, a low-pressure compressor and a high-pressure compressor, an annular combustion chamber, a high-pressure turbine and a low-pressure turbine and a gas exhaust nozzle.

[0004] The fan is composed of a central disc rotating around an axis of rotation. The axis of rotation is for example the longitudinal axis of the turbomachine. The central disc is surmounted by a plurality of blades allowing the initial compression of the air entering the turbomachine. The blades are possibly surrounded by a retention casing allowing the blades to be retained in the event of their breakage.

[0005] A fan blade is generally composed of a blade having an aerodynamic profile comprising a leading edge and a trailing edge connected by a pressure face and an extrados face opposite the pressure face. The blade further comprises an upper end and an opposite lower end connected to a root. The root is intended to cooperate with a corresponding cell of the central disc to fix the blade on the central disc.

[0006] Furthermore, in order to reduce the weight of the fan, the blade of the vane may be made of a composite material, typically an organic matrix composite (OMC) material. The composite material comprises a polymer matrix, for example, a thermoplastic or thermosetting matrix and fibers, such as carbon fibers or glass fibers, embedded in the matrix. The blade is for example made by a draping or injection molding process.

[0007] Furthermore, in order to protect the leading edge from wear by erosion and / or degradation caused by impacts with foreign bodies, the leading edge is covered with a typically metallic protective shield. The protective shield is assembled and fixed to the leading edge by gluing. For this purpose, the leading edge or the protective shield is coated with a layer of glue, then the protective shield is assembled on the leading edge. The assembly is then subjected to heat treatment to ensure the polymerization of the glue layer. The shield is thus fixed on the leading edge.

[0008] After manufacturing, each blade is mounted on the central disc according to its own inertia and its relative inertia with respect to its neighbors. Balancing the fan is essential to prevent rotation from inducing a force perpendicular to the axis of rotation and prematurely wearing the central disc and the turbomachine, as well as for better efficiency and optimal performance.

[0009] To balance the fan, it is necessary to balance the forces generated by the blades relative to the axis of rotation. The force generated by a blade is called the radial moment weight (RMW). The radial moment weight of a blade is equal to the mass of the blade multiplied by the distance between the center of gravity of the blade and the axis of rotation. When the radial moment weight of each blade is equal to that of the others, then the fan rotor is perfectly balanced. The life of the rotor depends partly on its balancing: the more balanced the rotor is, the less quickly it wears.

[0010] However, the manufacturing processes of the blades result in a significant dispersion of the radial moment weight of the blades. Thus, in order to perfectly balance the rotor, it is known to add balancing weights in the cone of the fan module at the time of mounting the fan on the turbomachine. Without such balancing, an unbalance appears and the rotor wears prematurely.

[0011] This solution is not entirely satisfactory in that it allows the radial moment weight to be adjusted on the complete set of blades of the fan, i.e. after the fan has been mounted and not on the blades individually. Furthermore, this solution uses added parts which complicates the mounting of the fan.

[0012] Therefore, the present invention aims to overcome the above drawbacks and thus aims to provide a method of manufacturing blades making it possible to limit the dispersion of the radial moment weight of the blades and a blade having a predetermined radial moment weight in order to limit the dispersion of the radial moment weight of the blades. Summary of the invention

[0013] To this end, the invention proposes a method of manufacturing a blade for an aircraft turbomachine, the blade comprising a root, the method comprising the following steps:

[0014] (a) providing a blade made of composite material, having an axis of elongation and comprising a leading edge and a trailing edge connected by a lower surface face and an upper surface face opposite the lower surface face,

[0015] (b) providing a protective shield,

[0016] (c) placing a layer of glue on an external surface of the blade or on a surface internal protective shield,

[0017] (d) assembling the metal protective shield on the blade, the leading edge being covered by the protective shield.

[0018] The method is characterized in that it further comprises the following step:

[0019] (e) inserting an insert into the glue layer, the insert having an internal cavity and extending along the axis of elongation parallel to the leading edge.

[0020] According to the method of the invention, an insert is inserted into the layer of glue. Indeed, the layer of glue has a thickness, which makes it possible to arrange the insert in this layer.

[0021] The insert has an internal cavity which allows, during the manufacture of the blade, to adjust if necessary the radial moment weight of the blade by filling at least part of the cavity with one or more materials. The radial moment weight of each blade can then be adjusted individually. The manufacturing method thus makes it possible to limit the dispersion of this parameter during manufacture and to provide blades having an adjusted radial moment weight.

[0022] The blades having, thanks to the invention, a radial moment weight corresponding to a reference radial moment weight, the risks of creating an unbalance during the assembly of the blades on the rotor are reduced. Thanks to the manufacturing method of the invention, it is possible to avoid the step of balancing the fan by adding balancing weights.

[0023] Furthermore, the mechanical properties of the blade are maintained since the insert is integrated into the thickness of the adhesive layer which is subjected to little stress during the operation of the turbomachine on which the blades are mounted.

[0024] The method according to the invention may comprise one or more of the following characteristics, taken in isolation from one another or in combination with one another:

[0025] — the composite material comprises a fibrous preform embedded in a matrix polymeric;

[0026] — the glue layer has a thickness, the insert being arranged in the thickness of the glue layer;

[0027] — the adhesive layer comprises an extrados fin arranged between the extrados face of the blade and the first lateral fin of the protective shield and an intrados fin arranged between the intrados face of the blade and the second lateral fin of the shield protection, the adhesive layer further comprising a central base connecting the extrados fin and the intrados fin, the central base being arranged between the leading edge and the central portion of the protective shield, the insert being arranged in the central base;

[0028] — in step (e), the internal cavity opens into an upper end of the layer glue opposite the foot of the dawn;

[0029] - in step (e), the insert is inserted into an upper portion of the glue layer opposite the foot;

[0030] - the method further comprises the following step (f), after step (e): (f) polymerize the glue layer;

[0031] - the insert has a cylindrical shape with a central axis parallel to the axis of elongation;

[0032] - in step (e), the internal cavity is delimited axially along the elongation axis by a lower transverse wall and an upper transverse wall and is delimited radially by a peripheral wall;

[0033] - the method comprises, after step (e), the following steps:

[0034] (g) cutting or machining the upper portion of the glue layer so as to access to the internal cavity of the insert,

[0035] (h) measuring the radial moment weight of the blade and comparing the radial moment weight measured with a reference radial moment weight,

[0036] (i) adding a predetermined amount of at least one first material into the cavity internal to adjust the radial moment weight of the blade;

[0037] - in step (i) a second material is added into the internal cavity, the first second materials with different density;

[0038] - the quantity of the first material or the sum of the quantities of the first and second materials is between 0g and 20g, preferably between 5g and 20g;

[0039] - the first material is lead.

[0040] The invention also relates to a blade for an aircraft turbomachine comprising:

[0041] - a blade made of composite material having an axis of elongation and comprising a leading edge and a trailing edge connected by a lower surface face and an upper surface face opposite the lower surface face,

[0042] - a protective shield fixed on the blade and covering the leading edge,

[0043] - a layer of glue placed between the protective shield and the blade which is intended to fix the protective shield on the blade.

[0044] The blade is characterized in that it further comprises an insert having an internal cavity, the insert being arranged in the layer of glue and extending along the elongation axis parallel to the leading edge, the internal cavity being intended to receive a first material.

[0045] The blade according to the invention may comprise one or more of the following characteristics, taken in isolation from one another or in combination with one another:

[0046] — the composite material comprises a fibrous preform embedded in a matrix polymeric;

[0047] — the glue layer has a thickness, the insert being arranged in the thickness of the glue layer;

[0048] — the adhesive layer comprises an extrados fin arranged between the extrados face of the blade and the first lateral fin of the protective shield and an intrados fin arranged between the intrados face of the blade and the second lateral fin of the protective shield, the adhesive layer further comprising a central base connecting the extrados fin and the intrados fin, the central base being arranged between the leading edge and the central portion of the protective shield, the insert being arranged in the central base. Brief description of the figures

[0049] Other characteristics and advantages will emerge from the following description of a non-limiting embodiment of the invention with reference to the appended drawings in which:

[0050] [Fig-1] [Fig.l] is a schematic representation of a half turbomachine aircraft;

[0051] [Fig.2] [Fig.2] is a schematic perspective representation of a blade according to the invention;

[0052] [Fig.3a] [Fig.3a] is a schematic representation of an upper end of the blade of [Fig.2];

[0053] [Fig.3b] [Fig.3b] is a partial cross-sectional view of the blade of [Fig.2];

[0054] [Fig.4a] [Fig.4a] is a schematic representation of an upper end of a blade according to the invention in a step of the method;

[0055] [Fig.4b] [Fig.4b] is a schematic representation of an upper end of a blade in another step of the process.

[0056] [Fig.5] [Fig.5] is a block diagram of the method of manufacturing a blade according to the invention. Detailed description of the invention

[0057] An aircraft turbomachine 1 is for example shown in [Fig.l]. The turbomachine 1 extends along a longitudinal axis X. The turbomachine 1 typically comprises, from upstream to downstream in the direction of flow of the gases F, a fan 2, a low-pressure compressor 3, a high-pressure compressor 4, at least one annular combustion chamber 5, a high-pressure turbine 6, a low-pressure turbine 7 and a gas exhaust nozzle (not shown).

[0058] The high pressure turbine 6 comprises a rotor which rotates a rotor of the high pressure compressor 4 via a high pressure shaft 8. The low pressure turbine 7 comprises a rotor which rotates the rotor of the low pressure compressor 3 and of the fan 2 via a low pressure shaft 9.

[0059] The rotor of the fan 2 is composed of a central disc 2a surmounted by a plurality of blades 20 regularly distributed over the circumference of the central disc 2a. The disc 2a is movable in rotation about the longitudinal axis X. The blades 20 are for example surrounded by an optional retention casing 11 intended to retain the blades 20 in the event of their rupture. The retention casing 11 has an internal surface coated with a layer of an abradable material 12. The layer of abradable material 12 is a layer which is capable of being worn by friction with the blades 20. The blades 20 according to the invention are thus for example blades 20 of the fan 2.

[0060] As best seen in [Fig.2], each blade 20 comprises a blade 21 and a protective shield 26. The blade 21 is for example secured to a fixing foot 22.

[0061] The blade 21 is made of composite material. The composite material comprises a matrix and fibers embedded in the matrix. The composite material is, for example, an organic matrix composite (OMC). The matrix is, for example, a thermoplastic or thermosetting polymer matrix. The fibers are, for example, carbon fibers or glass fibers. The fibers are, for example, organized in the form of a fiber preform. The blade 21 is, for example, made by resin transfer molding, by injection molding or by draping.

[0062] The blade 21 extends along an elongation axis Z. The elongation axis Z extends transversely relative to the longitudinal axis X of the turbomachine 1. The blade 21 has an upper end 21a and a lower end opposite the upper end 21a along the elongation axis Z. The upper end 21a faces the abradable layer 12. The root 22 is connected to the lower end and cooperates with a corresponding cell (not shown) of the central disc 2a in order to fix the blade 20 on the central disc 2a. The upper end 21a is therefore opposite the root 22.

[0063] The blade 21 has an aerodynamic profile. The blade 21 comprises a leading edge 23 and a trailing edge 24 connected by an extrados face 25a and an intrados face 25b opposite the extrados face 25a.

[0064] The protective shield 26 is fixed to the blade 21. It is intended to protect the leading edge 23 from external impacts and wear. The protective shield 26 is for example made of metallic material. The metallic material is for example titanium or steel. The protective shield 26 has an elongated shape along the axis of elongation Z. The protective shield 26 has a first free end and a second opposite end. The protective shield 26 extends along the blade 21, and in particular along the leading edge 23. The protective shield 26 thus extends along the leading edge 23 between the upper end 21a and the lower end. Preferably, the first end is aligned with the upper end 21a and the second end is aligned with the lower end, along the longitudinal axis X.

[0065] As best seen in [Fig.3b] for example, the protective shield 26 has a dihedral-shaped section. The protective shield 26 comprises a first lateral fin 26a and a second lateral fin 26b. The first and second lateral fins 26a, 26b are connected by a central portion 26c. The first lateral fin 26a extends over at least a portion of the extrados face 25a and the second lateral fin 26b extends over at least a portion of the intrados face 25b. The central portion 26c covers the leading edge 23. The central portion 26c has a thickness, as measured in a direction transverse to the elongation axis Z, greater than the thickness of the first and second lateral fins 26a, 26b respectively. The first and second lateral fins 26a, 26b are preferably tapered towards the trailing edge 24 of the blade 21. They respectively fit the extrados 25a and intrados 26b faces.Thus, the thicknesses of the first and second lateral fins 26a, 26b decrease towards the longitudinal ends of the protective shield 26 opposite the central portion 26c.

[0066] The protective shield 26 is fixed to the blade 21 by gluing. For this purpose, the blade 20 comprises a layer of glue 27 disposed between the protective shield 26 and the blade 21.

[0067] The adhesive layer 27 has an upper portion opposite the foot 22 and a lower portion opposite the upper portion. The upper portion of the adhesive layer 27 extends between the free end of the adhesive layer 27 and, for example, half the height of the adhesive layer 27.

[0068] The adhesive layer 27 has a U-shaped section. The adhesive layer 27 comprises an extrados fin 27a arranged between the extrados face 25a of the blade 21 and the first lateral fin 26a of the protective shield 26 and an intrados fin 27b arranged between the intrados face 25b of the blade 21 and the second lateral fin 26b of the protective shield 26. The adhesive layer 27 further comprises a central base 27c connecting the extrados fin 27a and the intrados fin 27b. The central base 27c is arranged between the leading edge 23 and the central portion 26c of the protective shield 26.

[0069] The central base 27c has a first thickness el, as measured in a direction transverse to the elongation axis Z, greater than second and third thicknesses e2, e3 respectively of the extrados and intrados fins 27a, 27b. The second and third thicknesses e2, e3 are advantageously identical.

[0070] The first thickness e1 is for example between 1 mm and 10 mm. The second thickness e2 is for example between 0.10 mm and 0.50 mm, preferably between 0.10 mm and 0.35 mm. The third thickness e3 is advantageously identical to the second thickness. The adhesive layer 27 is for example made of polymeric material preferably chosen from epoxy resins. The polymeric material has a density for example between 1 g / cm3 and 2 g / cm3.

[0071] According to the invention, the blade 20 further comprises an insert 28. The insert 28 is arranged in the adhesive layer 27. The insert 28 is therefore arranged in the thickness of the adhesive layer 27. The insert 28 is advantageously arranged in the central base 27c. The insert 28 is therefore advantageously arranged in the first thickness e1 of the adhesive layer 27. Indeed, the central base 27c is weakly stressed and contributes only slightly to the bonding quality of the protective shield 26 on the blade 21 unlike the extrados and intrados fins 27a, 27b. Thus, the addition of the insert 28 in this part of the adhesive layer 27 does not impact the bonding strength of the protective shield 26 on the blade 21. The properties of the blade 20 are preserved.

[0072] The insert 28 has an elongated shape along the leading edge 23. Advantageously, the insert 28 is arranged in the upper portion of the adhesive layer 27. The insert 28 has a cylindrical and elongated shape along a central axis Y. The central axis Y is parallel to the elongation axis Z of the blade 21. The insert 28 has a peripheral wall 28b. The peripheral wall 28b delimits the insert 28. It further extends along the central axis Y between an upper end and a lower end. The upper and lower ends are advantageously closed. As seen in [Fig.3a], the lower end has a lower transverse wall 28c and the upper end has an upper transverse wall 28d opposite the root 22.

[0073] The length H of the insert 28 as measured along the central axis Y is advantageously between 50 mm and 300 mm, for example between 150 mm and 200 mm. The insert 28 is for example made of polymeric material. The polymeric material is chemically compatible with the material of the adhesive layer 27. This makes it possible to guarantee the longevity of the interface between the adhesive layer 27 and the insert 28.

[0074] According to a first exemplary embodiment illustrated in [Fig.3a], the insert 28 has a circular cross-section. The internal diameter of the insert 28 is advantageously between 1 mm and 5 mm.

[0075] According to another exemplary embodiment shown in [Fig.3b], the insert 28 has an elliptical cross-section. According to this embodiment, the insert 28 has a large diameter L measured along the major axis, for example between 2 mm and 5 mm, and a small diameter 1 measured along the minor axis, for example between 1 mm and 4 mm, the large diameter L being greater than the small diameter 1.

[0076] As visible in [Fig.3b], the insert 28 has an internal cavity 28a. The internal cavity 28a is delimited radially with respect to the central axis Y or the elongation axis Z by the peripheral wall 28b and axially along the central axis Y or the elongation axis Z by the lower and upper transverse walls 28c, 28d.

[0077] The insert 28 optionally comprises at least one first material (not shown) arranged in the internal cavity 28a. The quantity of the first material is advantageously between 0g and 20g, preferably between 5g and 20g and even more preferably between 10g and 20g. The first material has a density advantageously greater than the density of the materials of the protective shield 26 and of the blade 21. The density of the first material is for example between 5 g / cm3 and 15 g / cm3, typically between 10g / cm3 and 12g / cm3. The first material is for example lead. The first material is for example powder or balls, in particular micro balls. The first material makes it possible to adjust the radial moment weight of the blade 20 relative to a reference radial moment weight.

[0078] In order to fill the remainder of the internal cavity 28a and / or to adjust more precisely the radial moment weight of the blade 20, the insert 28 optionally comprises a second material (not shown) arranged in the internal cavity 28a. The second material has a density different from the density of the first material. For example, the density of the second material is lower than the density of the first material. The quantity of the sum of the first and second materials is advantageously between 0g and 20g, preferably between 5g and 20g and even more preferably between 10g and 20g. The ratio between the first material and the second material is between 0 and 1. The ratio is calculated as the ratio between the quantity of the first material and the sum of the quantities of the first and second materials.

[0079] The second material is for example polymeric. The polymerization temperature of the polymeric material is for example equal to the ambient temperature. The ambient temperature is the temperature in the air of the ambient environment. The ambient temperature is typically between 15°C and 30°C. This makes it easier to seal the internal cavity 28a.

[0080] The polymeric material is chosen from thermoplastics or thermosets, such as an epoxy type resin. The second material is for example identical to the material of the adhesive layer 27. This makes it possible to simplify the manufacturing process since the behavior of the materials is identical.

[0081] A method of manufacturing the above blade 20 will now be described on the basis of [Fig. 5]. The method according to the invention comprises a first step (a) of providing the blade 21. As described previously, the blade 21 is made of composite material and has a leading edge 23 and a trailing edge 24 connected by an extrados face 25a and a intrados face 25b opposite the extrados face. The blade 21 is for example made of organic matrix composite material. The blade 21 is produced for example by a resin transfer molding (RTM) process, by injection molding or by a draping process.

[0082] The method further comprises a step (b) of providing the protective shield 26. The protective shield 26 is for example produced by stamping, forming or any other known mechanical process. Step (b) can be carried out before, after or in parallel with step (a).

[0083] Furthermore, the method comprises a step (c) in which the adhesive layer 27 is arranged on an external surface of the blade 21 or on an internal surface of the metal protective shield 26, the internal surface of the metal protective shield 26 being the surface facing the external surface of the blade 21 after assembly. The adhesive layer 27 is for example deposited manually. It is for example deposited in the form of a flexible adhesive film.

[0084] In a step (d) of the method, the protective shield 26 is assembled on the blade 21. By assembled, it is understood that the protective shield 26 is carried opposite the leading edge 23.

[0085] The method comprises an additional step (e) of inserting the insert 28 into the thickness of the adhesive layer 27, for example into the first thickness e1, i.e. into the central base 27c. As described previously, the insert 28 has an internal cavity 28a delimited radially by the peripheral wall 28b and axially by the lower transverse wall 28c. During step (e), the internal cavity 28a is further delimited axially by the upper transverse wall 28d as shown in [Fig.4a]. The upper transverse wall 28d is opposite the lower transverse wall 28c along the central axis Y. Step (e) can be carried out before, after, or in parallel with step (d) of assembling the metal protective shield 26 on the leading edge 23.

[0086] Furthermore, after the insertion of the insert 28 during step (e), the adhesive layer 27 is polymerized during a step (f). During this step, the blade 20 is subjected to a heat treatment of between 50°C and 250°C. For this purpose, the blade 20 is for example placed in an oven. This makes it possible to fix the metal protective shield 26 on the leading edge 23.

[0087] Furthermore, in order to ensure that the protective shield 26 is correctly placed on the blade 21, in particular that the protective shield 26 and the blade 21 are correctly aligned, a step (g) of cutting or machining the upper portion of the glue layer 27 is made. The cutting or machining is carried out along a plane P transverse to the central axis Y of the insert 28 or the elongation axis Z of the blade 21. The plane P is parallel to the longitudinal axis X of the turbomachine 1. The cutting is carried out over the entire width of the blade 20, that is to say that the upper portion of the glue layer 27, of the blade 21 and of the protective shield 26 is removed. Step (g) is carried out so as to access the internal cavity 28a of the insert 28. The internal cavity 28a thus opens onto a free end of the glue layer 27 opposite the root 22. Indeed, during this step, the upper transverse wall 28d of the insert 28 is removed as visible in [Fig.4b]. The internal cavity 28a being accessible, it is then possible to adjust the radial moment weight of the blade 20 subsequently as required.

[0088] In order to verify that the radial moment weight of the blade 20 corresponds to the desired radial moment weight, a step (h) of measuring the radial moment weight of the blade 20 is carried out. The measured radial moment weight is then compared with a reference radial moment weight. The reference radial moment weight is based on the radial moment weight of a population of blades, and / or on a table of values ​​established beforehand. This makes it possible to determine the parameters of the next step.

[0089] If it is concluded that the radial moment weight of the blade 20 must be adjusted, the internal cavity 28a being accessible, a step (i) of adding a quantity determined at the end of step (h) of the first material in the internal cavity 28a is carried out in order to adjust the radial moment weight of the blade 20 to the reference radial moment weight. In order to complete the space in the cavity 28a or to adjust more precisely the radial moment weight of the blade 20, during step (i) the second material can be added in the internal cavity 28a. The first and second materials can be added in the form of a mixture or separately. The first and second materials are advantageously added in the form of powder or granules in order to facilitate the handling of the materials as well as the filling of the adjustment cavity 28.

[0090] Then, optionally, in a following step (j), the internal cavity 28a is closed. For this purpose, the second material is placed in the internal cavity 28a. Optionally, the material is subjected to a heat treatment for melting when the material is in powder form. For this purpose, a free end of the blade 20 opposite the root 22 is subjected to a temperature equal to or greater than the melting temperature of the polymeric material. Advantageously, the polymeric material has a polymerization temperature substantially equal to ambient temperature. This makes it possible to dispense with an additional heat treatment step. The polymerization of the material makes it possible to reform the upper transverse wall 28c to close the internal cavity 28a.

[0091] Step (h) of measuring and comparing the radial moment weight of the blade 20 may be repeated after step (i) in order to ensure that the radial moment weight of the blade 20 after adjustment corresponds to the desired value. This step also allows the correlation table to be completed between the variation in radial moment weight and the quantities of the first and second materials.

[0092] Thus, according to the invention, it is possible to adjust the radial moment weight of the blades 20 individually during their manufacture. This makes it possible to homogenize this parameter during manufacture. It is for example possible to adjust the radial moment weight of the blades 20 by at least 5g.cm, for example from 5g.cm to 20g.cm and for example by 15g.cm.

[0093] Furthermore, the addition of the insert 28 does not impact the mechanical properties of the blade 20 since it is advantageously inserted in a lightly stressed area of ​​the blade 20. The bonding force between the metal protective shield 26 and the blade 21 is also not affected thanks to the possibility of adding the insert 28 in the central base 27c.

Claims

Claims

1. A method of manufacturing a blade (20) for an aircraft turbomachine (1), the blade (20) comprising a root (22), the method comprising the following steps: (a) providing a blade (21) made of composite material, having an elongation axis (Z) and comprising a leading edge (23) and a trailing edge (24) connected by a pressure face (25b) and an extrados face (25a) opposite the pressure face (25b), (b) providing a protective shield (26), (c) placing a layer of adhesive (27) on an external surface of the blade (21) or on an internal surface of the protective shield (26), (d) assembling the protective shield (26) on the blade (21), the leading edge (23) being covered by the protective shield (26), characterized in that the method further comprises the following step: (e) inserting an insert (28) into the layer of glue (27), the insert (28) having an internal cavity (28a) and extending along the elongation axis (Z) parallel to the leading edge (23).

2. Method according to claim 1, characterized in that, in step (e), the insert (28) is inserted into an upper portion of the glue layer (27) opposite the foot (22).

3. Method according to one of claims 1 or 2, characterized in that the method further comprises the following step (f), after step (e): (f) polymerizing the layer of glue (27).

4. Method according to any one of the preceding claims, characterized in that the insert (28) has a cylindrical shape with a central axis (Y) parallel to the elongation axis (Z).

5. Method according to any one of the preceding claims, characterized in that, in step (e), the internal cavity (28a) is delimited axially along the elongation axis (Z) by a lower transverse wall (28c) and an upper transverse wall (28d) and is delimited radially by a peripheral wall (28b).

6. Method according to any one of claims 2 to 5, characterized in that it comprises, after step (e), the following steps: (g) cutting or machining the upper portion of the glue layer (27) so as to access the internal cavity (28a) of the insert (28), (h) measuring the radial moment weight of the blade (20) and comparing the weight radial moment measured with a reference radial moment weight, (i) adding a predetermined amount of at least one first material into the internal cavity (28a) to adjust the radial moment weight of the blade (20).

7. Method according to the preceding claim, characterized in that, in step (i) a second material is added into the internal cavity (28a), the first and second materials having a different density.

8. Method according to one of claims 6 or 7, characterized in that the quantity of the first material or the sum of the quantities of the first and second materials is between 0g and 20g, preferably between 5g and 20g.

9. A method according to any one of claims 6 to 8, characterized in that the first material is lead.

10. Blade (20) for an aircraft turbomachine (1) comprising: - a blade (21) made of composite material having an elongation axis (Z) and comprising a leading edge (23) and a trailing edge (24) connected by a lower surface face (25b) and an upper surface face (25a) opposite the lower surface face (25b), - a protective shield (26) fixed to the blade (21) and covering the leading edge (23), - a layer of adhesive (27) arranged between the protective shield (26) and the blade (21) which is intended to fix the protective shield (26) to the blade (21), the blade (20) being characterized in that it further comprises: - an insert (28) having an internal cavity (28a), the insert (28) being arranged in the layer of adhesive (27) and extending along the elongation axis (Z) parallel to the leading edge (23), the internal cavity (28a) being intended to receive a first material.

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