Sealing member for a moving blade

Abstract

The invention relates to the connection of a sealing member to a blade. One aspect of the invention relates to a turbine engine rotary assembly comprising a disc (3) and at least one blade (1') comprising: - a stilt wall (14') extending radially from a root (13) situated in a recess of the disc comprising a first circumferential end surface (14a), - a platform (16') which extends at the radially outer end of the stilt (14') and is mounted circumferentially end-to-end with another stilt (14') of another circumferentially adjacent blade (1'), - the platform (16) or the stilt (14') comprising a first coupling element (15'), the assembly also comprising a sealing member (5') mounted in a cavity (6) comprising a second coupling element (51') nested with that of the blade (1') for axially retaining the sealing member (5') in the cavity (6) in both directions.

Description

DESCRIPTION TITLE: Sealing member for a moving blade TECHNICAL FIELD OF THE INVENTION

[0001] The technical field of the invention is that of sealing at the blade roots of a turbomachine turbine rotor wheel.

[0002] The present invention relates to a rotating turbomachine assembly comprising blades and sealing members and in particular a connection of the sealing member with the blade. TECHNOLOGICAL BACKGROUND OF THE INVENTION

[0003] It is known to use a mobile turbine wheel in turbomachines, such as a low pressure turbine, comprising a disc provided at its periphery with cells carrying blades.

[0004] In particular, it is known from document FR3102506, of which figure 1 is part of the prior art, belonging to the applicant, a turbine wheel comprises a disc 3 and blades 2 mounted on the disc 3 in a manner regularly distributed around the disc 3. Each blade 2 comprises a fixing foot 23 mounted in cells 30 of the disc 3 formed by teeth 31. The cells 30 or grooves are regularly distributed around the periphery of the disc 3 and define between them the teeth 31. Each blade 2 further comprises a stilt 24 which extends radially outwards the root 23 of the blade 2. Figure 2 represents a stilt 24, a root 23 of a blade 2. The stilt 24 comprises a wall 24r extending radially outwards from the root 23 and a platform 26 which extends at the radially external end of the stilt 24. Typically, each blade 2 of a turbine wheel comprises a blade 27 connected at its radially internal end to the platform 26.

[0005] The stilt 24 further comprises four walls (three of which are circled in FIG. 2) each located on one of the axial and lateral sides of the central wall 24r. Thus, two of the four walls are lateral on a first axial side and the other two are on the other axial side. On the first axial side, a first upstream lateral wall 24ac and a second upstream lateral wall 24bc on the other lateral side (referenced in FIG. 1) extend from an upstream axial end of the axial wall 24r. On the other axial side, a first downstream wall 24ad and a second downstream lateral wall 24bd (referenced in FIG. Figure 2, not shown in Figure 1) each extend from the downstream axial end of the axial wall 24r. The walls extend transversely to the axis of rotation of the turbomachine but are not necessarily radial. The upstream walls of the blades are thus arranged circumferentially end to end and the same is true of the downstream walls.

[0006] When the impeller is assembled, the blade platforms extend circumferentially end-to-end around the disc, being spaced from each other by small clearances J separating their respective platforms.

[0007] The platform 26 forms with the stilt walls 24 of each blade a first and second half-cavities 24a, 24b, which forms with the half-cavity of a neighboring blade (contiguous blade) a cavity 213.

[0008] Each wall also helps limit the reintroduction of air into the cavities.

[0009] It is further known to mount in these cavities 213, sealing members to limit leaks between the platforms, represented by an inter-platform clearance J in FIG. 1. These leaks correspond to gas circulating from upstream to downstream of the disk, between the inter-platform clearances, without driving a blade. These members can also be designed to ensure damping of the vibrations to which the blades are subjected during operation. Thus, each sealing member 212, also called a “candy”, is engaged in a cavity 213 delimited by two half-cavities 24a, 24b of two circumferentially adjacent blades.

[0010] The sealing members are thus held axially on one axial side by the pair of upstream lateral walls comprising the upstream lateral walls 24ac with the second upstream lateral wall 24bc of the adjacent blade and on the other axial side, by the pair of downstream walls comprising the first downstream wall 24ad and the second downstream lateral wall 24ad of the adjacent blade. Stops on these walls are also known to retain the sealing member. However, there is an axial clearance between the sealing member and one of the two pairs of walls causing the latter to move axially, which can lead to vibrations and gas leak problems between one of these two pairs and the uncovered inter-platform clearance J. In particular, this axial clearance exists due to manufacturing constraints, the sealing member, the walls of the blades, and assembly constraints which can lead to an offset axial between two blades. It is known from the document FR3027950 and from the document EP1507960 of the applicant, sealing members comprising axial end walls comprising strips elastically deformed against at least one pair of walls to avoid this play. However, on the one hand these elastic walls require pairs of walls, and on the other hand there are problems of assembly to ensure that the sealing member is mounted against the platforms of the two blades and of service life due to thermal expansion and contraction by the thermal stresses on these sealing members.

[0011] In operation, the sealing member is pressed by centrifugal effect or held elastically against internal faces of the platforms of the two adjacent blades, so as to limit gas leaks through the inter-platform clearance J separating the sides of these two circumferentially adjacent blades.

[0012] In addition, there are blades made of ceramic matrix composite (CMC) material. The use of this type of material makes it possible to reduce the weight of the blades and increase their resistance to high temperatures, but also requires reviewing the geometry of the blades, in particular the platforms. Indeed, it is relatively complicated to produce a platform with a structure similar to that of the prior art, in particular it is complicated to produce the stilt walls which increases the cost and in addition are not very robust (low mechanical strength). Such a structure generates in particular problems of twisting of the fibers of the material during manufacturing. Of course, this problem of simplification of the structure of the platforms can also arise with other types of blades.There is therefore a need to reduce costs for CMC Ceramic Matrix Composite blades while avoiding leaks through the inter-platform clearance separating two circumferentially adjacent blades, which corresponds to a loss of performance, on the one hand in that it does not generate driving force and on the other hand in that it heats the disc teeth, which requires increasing their cooling with additional fresh gas taken upstream, which induces a further drop in performance.

[0013] It is understood that the shape of each device is imposed by the shape of the blade, more specifically by the geometry of the cavity. To assemble the moving wheel, the operator proceeds as follows. First, the operator engages a blade root, from a downstream end for example, in a cell of the disc. The operator then simultaneously mounts a blade / sealing device pair and repeats this operation until the penultimate blade is mounted. The last blade must be mounted at the same time as the two sealing devices on either side of the blade's Péchasse. This requires technical know-how and training, and it is common for the positioning of this last blade to take as much time as the positioning of all the blades previously positioned.

[0014] There is also a need to reduce assembly time, particularly that of the last dawn.

[0015] It is known from document FR3006364A1 to replace on one of the axial sides, the walls by an annular sealing flange mounted in the upstream or downstream part of the disc, the flange extending radially between the platforms and the disc. The flange comprises means for coupling in rotation with at least one of the sealing members. The operation thus consists of inserting teeth of this flange once all the blades and sealing members are arranged, in hollow zones of the disc so as to be able to insert axially. Once this insertion is carried out, the pivoting of the flange relative to the disc, by a determined angular value, makes it possible to position the teeth of the flange opposite the teeth of the crown, and thus to avoid accidental removal of the flange.

[0016] However, this flange is expensive and also requires the sealing members to be inserted horizontally before inserting this flange to avoid falling.

[0017] There is therefore a need to improve the performance of a sealing member between two blades, particularly in CMC. SUMMARY OF THE INVENTION

[0018] The invention provides a solution to one of the problems mentioned above, by making it possible to have a blade comprising a stilt comprising a coupling element coupled by male-female interlocking with an axial coupling element complementary to a sealing member to hold the sealing member axially in a cavity forming a housing for the sealing member, formed with a neighboring blade.

[0019] The invention aims in particular to provide a simple, effective and economical solution for the axial holding of the sealing member, by proposing a blade, for example made of CMC, the structure of which can be simplified, while ensuring the aforementioned sealing functions.

[0020] One aspect of the invention relates to a rotating assembly of a turbomachine with a rotation axis comprising: a disk centered on the axis which has at its peripheries cells delimited circumferentially by teeth of the disk, blades mounted circumferentially adjacent each in a respective cell of the disk, each blade comprising: a root mounted in a respective cell of the disk, the root having a shape configured to allow mounting of the root in the respective cell of the disk, a stilt formed by a wall which extends radially with respect to the axis towards the outside of the root, the stilt wall being delimited by a first circumferential end surface, a second circumferential end surface opposite the first circumferential end surface and two axial end edges opposite each other,a platform which extends at the radially outer end of the Péchasse and which is situated circumferentially end-to-end with another platform of another circumferentially adjacent blade, and a blade which extends radially outwardly from the platform, at least one sealing member mounted in a cavity delimited on the one hand, by the disc and on the other hand, by the stilts and the platforms of the blade and of the other circumferentially adjacent blade, in which: the platform or Péchasse of the blade comprises a first coupling element coupled by male-female interlocking with a second coupling element extending from a wall of the sealing member so as to retain the member, sealing with respect to the cavity, axially in both directions while allowing the sealing member to be pressed by centrifugal force against the platforms of the two blades, the sealing member further comprises an upstream surface and a downstream surface and in that the cavity is open axially at least on one downstream or upstream side on all respectively the downstream surface or upstream surface.

[0021] Thanks to the invention, the sealing member is retained axially by its second coupling element coupled by male-female interlocking with the first coupling element of the platform or stilt. The male-female interlocking makes it possible to avoid problems of axial clearances unlike the case of the prior art in which the rotating members are pressed against a stop or wall of the blade. Indeed, thanks to the male-female interlocking of the coupling elements, the sealing member has an axial clearance (or not because the interlocking can be tightened) solely depending on the manufacturing tolerances of these coupling elements. Thus the rotating assembly has a sealing member maintained axially in a reliable manner (without problem of thermal stresses). In addition, the sealing member can always be pressed by centrifugal force against the platforms of the two blades, thus making it possible to avoid assembly errors.

[0022] Furthermore, the invention makes it possible to operate with blades without an upstream and / or downstream wall, thereby simplifying the manufacture of CMC blades. Furthermore, the insertion of the last sealing member of the wheel can be inserted axially between the two blades, deforming elastically until the two coupling elements cooperate. Assembly is thus simplified.

[0023] In the application, "a first coupling element coupled by male-female interlocking with a second coupling element" means that the first or second coupling element is the female element (hole) and respectively the second or first coupling element is the male element (projection or protrusion) inserted into the female element (hole). Furthermore, "second coupling element extending from a wall of the sealing member" means that the second coupling element is a male part (projection or protrusion) or female (hole) of the sealing member connected to a wall together forming one side (one face) of the sealing member.

[0024] The coupling elements are therefore complementary, that is to say they have two complementary shapes to fit into each other and mechanically couple the blade to the sealing member in both axial directions.

[0025] Finally, the fact that the sealing member further comprises an upstream surface and a downstream surface and that the cavity is axially open at least on one downstream or upstream side on all of the downstream surface or upstream surface respectively. This allows the sealing member to be inserted into the cavity. Furthermore, this allows the stilt to be without a wall axially closing the cavity.

[0026] In addition to the characteristics which have just been mentioned in the preceding paragraph, the turbine wheel according to one aspect of the invention may have one or more additional characteristics among the following, considered individually or according to all technically possible combinations:

[0027] According to one embodiment, the cavity is open on the upstream and downstream axial side and Péchasse is only the stilt wall.

[0028] According to one embodiment, the protrusion is a plastic deformation of the wall of the sealing member comprising the circumferential end surface.

[0029] According to one embodiment, the Péchasse wall comprises the first circumferential end surface, the second circumferential end surface opposite the first circumferential end surface and the two axial end edges opposite each other.

[0030] According to one embodiment, the first coupling element is a male coupling element inserted into a groove of the second coupling element, or the second coupling element is a male coupling element inserted into a groove of the first coupling element.

[0031] According to an example of this embodiment, the male coupling member has a T-shape, the horizontal portion of the T-shape of the male coupling member being located in the female coupling member and the vertical portion of the T-shape of the male coupling member extending from a wall of the blade or sealing member to the horizontal portion of the T-shape. Thus a T-shape allows the coupling element of the sealing member extending from one of its walls to be fitted with the coupling element of one of the walls of the stilt or the platform of the blade while having these two walls spaced apart from each other.

[0032] According to an example of this previous embodiment, the male coupling element is a protrusion projecting from a surface of a wall of the blade or the sealing member and the female coupling element is a housing for receiving the protrusion, the female coupling element extending from a surface of a wall respectively of the sealing member or the blade

[0033] According to an implementation of this example of this embodiment, the second coupling element comprises a base extending from the surface of the wall of the blade, and an anchor comprising the complementary shape of the housing forming the first coupling element by filling it.

[0034] According to an example of this embodiment, the hole forming the female coupling element is through.

[0035] According to one embodiment, the sealing member comprises a circumferential end surface against the first circumferential end surface of the stilt, the second coupling element extending from the circumferential end surface of the sealing member and the first coupling element extending from the first circumferential end surface of the stilt. This makes it possible to have a circumferential fit between the sealing member and one of the two blades forming the cavity housing it. The circumferential fit makes it possible to radially connect the blade to the sealing member.

[0036] According to one embodiment, the sealing member is hollow. This makes it possible to lighten the rotating assembly.

[0037] According to one embodiment, the sealing member has first and second circumferential end walls which each have a shape complementary respectively to the first circumferential end surface of the stilt and to a second circumferential end surface of a stilt of a neighboring blade. This makes it possible to match the shape of the cavity and therefore to limit leaks.

[0038] According to one embodiment, wherein the first and a second circumferential end walls are curved.

[0039] According to one embodiment: the sealing member comprises a radially external end surface, the platform comprises a first and a second circumferential end edge (also called a wall) each having respectively a first radially internal surface and a second radially internal surface each delimiting respectively the cavity forming the housing of the sealing member and a cavity forming a housing of a second sealing member, the first radially internal surface and the second internal surface each being respectively opposite the radially external end surface of the sealing member and a radially external end surface of the second sealing member, an inter-platform clearance is formed between the first circumferential end edge and the second circumferential end edge of a circumferentially adjacent blade,the radially outer end surface of the sealing member extends radially under the interplatform clearance.,

[0040] According to one embodiment, the platform comprises a first and a second circumferential end wall (or edge) each extending respectively towards a first and a second other circumferential end wall of a first and second other blade circumferentially adjacent to this blade, each of these circumferential end walls comprising a first radially internal surface delimiting the cavity housing the sealing element, the first coupling element extends from the first radially internal surface of the first circumferential end wall of the platform, the sealing member comprises a radially outer end surface partially facing the first radially inner surface of the first circumferential end wall of the platform, the second coupling element extending from the radially outer end surface of the member.

[0041] The invention and its various applications will be better understood by reading the following description and examining the accompanying figures. BRIEF DESCRIPTION OF THE FIGURES

[0042] The figures are presented for information purposes only and in no way limit the invention.

[0043] [Fig. 1] shows a schematic representation of a radial section of a portion of a rotating turbomachine assembly according to the prior art, comprising blades mounted on a disc and a sealing member between two blades.

[0044] [Fig. 2] represents a three-dimensional view of a blade according to the prior art.

[0045] [Fig. 3] represents a three-dimensional view of a blade of a rotating assembly of a turbomachine according to an example of a first embodiment.

[0046] [Fig. 4] represents a three-dimensional view of a sealing member of the rotating assembly of the turbomachine according to the example of the first embodiment.

[0047] [Fig. 5] represents a sectional view of a part of the rotating assembly of the turbomachine according to the example of the first embodiment

[0048] [Fig. 6] represents a three-dimensional view of an assembly of the rotating turbomachine assembly according to the example of the first embodiment, comprising the blade of FIG. 3 and the sealing member of FIG. 4.

[0049] [Fig. 7] represents a three-dimensional view of a disk and a blade of the rotating assembly of a turbomachine according to a second example of the first embodiment.

[0050] [Fig. 8] represents a three-dimensional view of a part of the rotating assembly of the turbomachine according to this second example of the first embodiment.

[0051] [Fig. 9] represents a section of the part of the rotating assembly of the turbomachine according to this first example of the first embodiment.

[0052] [Fig. 10] represents a three-dimensional view of a blade of the rotating turbomachine assembly according to an example of a third embodiment

[0053] [Fig. 11] represents a section of the part of the rotating assembly of the turbomachine according to the example of the third embodiment. DETAILED DESCRIPTION

[0054] The figures are presented for information purposes only and in no way limit the invention.

[0055] The invention relates to a rotating assembly of a turbomachine with an X axis of rotation, which may be a mobile turbine wheel. The rotating assembly of a turbomachine with an X axis of rotation comprises a disc 3 centered on the X axis, blades 1 and sealing members 5. The disc 3 is such as that of FIG. 1 described in the prior art section. The disc 3 has at its periphery cells 30 and teeth 31 alternating circumferentially, such that two neighboring teeth 31 delimit a cell 30.

[0056] Figure 3 represents a three-dimensional view of a part of one of the blades 1 of a rotating assembly of a turbomachine according to a first example of the first embodiment, Figure 4 represents a three-dimensional view of one of the sealing members 5 of the rotating assembly of the turbomachine, Figures 5 and 6 respectively represent a radial section and a three-dimensional view of a part of the rotating assembly of the turbomachine.

[0057] Each blade 1 comprises a root 13 mounted in a cell 30 of the disc 3. The root 13 has a shape configured to allow mounting of the root 13 in a respective cell 30 of the disc, between two teeth 31 of the disc 3 to retain the blade 3 radially against centrifugal force and gravity.

[0058] The blade 1 comprises a stilt 14 which is in this case formed by a wall which extends from the root 13 radially with respect to the axis X towards the outside. The stilt 14 comprises a first circumferential end surface 14a, a second circumferential end surface 14b opposite the first circumferential end surface 14a and a first and a second axial end edge 14c, 14d, also called upstream axial end edge 14c and downstream axial end edge 14d (upstream and downstream being the direction of the air flow between the blades). In this embodiment, each axial end edge 14c, 14d is free. Each axial end edge 14c, 14d joins the first to the second circumferential end surface 14a, 14b.

[0059] The first circumferential end surface 14a and the second circumferential end surface 14b may be radially and / or axially curved, in this example the first circumferential end surface 14a is axially concave and the second circumferential end surface 14b is axially convex (but this may be reversed concave for the second circumferential end surface 14b and convex for the first circumferential end surface 14a). The first circumferential end surface 14a and the second circumferential end surface 14b may also be planar.

[0060] In this embodiment, the blade 1 comprises a first coupling element 15 extending from the circumferential end surface 14a. In this embodiment, the first coupling element 15 is a male coupling element, in this case it is a protruding protrusion extending from the circumferential end surface 14a. The first coupling element 15 is in this case spaced from the first and second axial end edges 14c, 14d. The function of this first coupling element 15 is explained below.

[0061] The blade 1 further comprises a platform 16 extending from the stilt 14 opposite the foot 13.

[0062] The platform 16 extends at the radially outer end of Péchasse 14 and is mounted circumferentially end-to-end with another platform of another blade circumferentially adjacent transversely with respect to Péchasse 14, forming walls extending transversely from each circumferential end surface 14a, 14b and each axial end edge 14c, 14d. The circumferentially adjacent blade is referred to hereinafter as the neighboring blade. In this case, the platform 16 is inclined with respect to Péchasse 14, such that the platform 16 is closer to the root 13 on the upstream side than from the downstream side. According to another example, the platform 16 is inclined with respect to Péchasse 14 in the other direction, that is to say that the platform 16 is closer to the root 13 on the downstream side than from the upstream side.According to another example, the platform 16 extends axially perpendicular to Péchasse 14, that is to say that the platform 16 is equidistant from the foot 13 on the downstream side and on the upstream side. The platform is perpendicular to each circumferential end surface 14a, 14b.

[0063] The platform 16 thus comprises, in this example, an upstream wall 16c extending in a radially inclined manner from the first axial end edge 14c of the stilt 14 forming a spoiler extending axially upstream.

[0064] The platform 16 thus comprises in this example, a downstream wall 16d inclined radially from the second axial end edge 14d of Péchasse 14 forming a spoiler extending axially downstream.

[0065] The platform 16 thus comprises a first circumferential end wall 164a and a second circumferential end wall 164b each extending respectively from the first circumferential end surface 14a, and from the circumferential end surface 14b. The first circumferential end wall 164a thus comprises a first radially internal surface 16a extending transversely from the first circumferential end surface 14a of Péchasse 14 and the second circumferential end wall 164b comprises a second radially internal surface 16a extending from the second circumferential end surface 14b.These two walls 164a, 164b are in this example inclined in the axial direction (that is to say that the downstream end is further away from the foot 13 than the upstream end of these walls) relative to Péchasse 14 but the inclination can be reversed or even without inclination (the platform 16 extends axially perpendicularly relative to Péchasse 14) as mentioned previously. The first and second circumferential end walls 164a, 164b are also each called respectively first and second circumferential end edges.

[0066] In the following, to simplify the description, the term "radially" can be deleted in the characteristics of the first or second radially internal surfaces 16a, 16b which can therefore be called the first or second internal surface 16a, 16b.

[0067] The first internal surface 16a thus extends from the first circumferential end surface of Péchasse 14 towards a second internal surface 16b of another platform 16 of a neighboring blade 1 mounted in an adjacent cell of the disc 3. A cavity 6 forming a housing for a sealing member 5 is formed between the two neighboring blades and the disc 3, more precisely delimited radially between a tooth 31 of the disc 3 and two internal surfaces 16a, 16b of two platforms 16 of two neighboring blades and circumferentially delimited between the first circumferential end surface 14a of the stilt 14 of the blade 1 and the second circumferential end surface 14b of the stilt 14 of the other neighboring blade 1. The cavity 6 forming the housing of the sealing member 5 is axially open at least at one axial end, in this case at both axial ends. The cavity 6 is axially open on both sides in these examples of these embodiments. The blades 1 'are in this case made of CMC composite but it could be metallic.

[0068] The first internal surface 16a therefore defines, with the second internal surface 16b of the circumferentially neighboring blade, an upper wall of the housing 6 of the sealing member 5.

[0069] In other words, the first internal surface 16a and the first circumferential end surface 14a together form a first volume of a half-housing of the housing of the sealing member 5 and the second internal surface 16b and the second circumferential end surface 14b together form a half-volume of another housing 6 of another sealing member 5 formed with another neighboring blade.

[0070] The sealing member 5 (shown alone in FIG. 4), also called a candy, comprises a radially external end surface 56a, a part of which is opposite the first internal surface 16a of the platform 16 of the blade 1 and another part is opposite the second internal surface 16b of the platform of the neighboring blade (shown in FIG. 5).

[0071] Another sealing member 5 (not shown) also comprises a radially end surface 56a, a part of which is mounted opposite the second internal surface 16b of the platform 16 of the blade 1 and another part of this radially external end surface 56a is opposite the first radially internal external surface 16a of the platform of the other neighboring blade (not shown).

[0072] In the following, to simplify the description, the term "radially" can be deleted in the feature radially outer end surface 56a which can therefore be called outer end surface 56a.

[0073] In this example, the outer end surface 56a of each sealing member 5 is in contact with the first and second surfaces internals 16a, 16b of two circumferentially neighboring platforms 16 of two circumferentially neighboring blades.

[0074] The sealing member 5 further comprises an upstream surface 54c and a downstream surface 54d.

[0075] The sealing member 5 further comprises a first and a second circumferential end surface 54a, 54b (one is visible in FIGS. 4 and 5 and the other in FIGS. 5 and 6) mounted facing respectively the first circumferential end surface 14a, and the second circumferential end surface 14b of the neighboring blade.

[0076] The upstream surface 54c and the downstream surface 54d each connect the first and second circumferential end surfaces 54a, 54b.

[0077] The sealing member 5 is in this case hollow but could be solid. Here, the sealing member 5 therefore comprises two circumferential end walls, an upstream wall, a downstream wall and a radially external wall.

[0078] The sealing member 5 further comprises a second coupling element 51 fitted with the first coupling element 15 of the blade, to axially retain in both directions the sealing member 5 in the cavity 6. In this case, the second coupling element 51 is a female coupling element, in this case a hole extending from the circumferential end surface 54a, which may be through or as in this example is a deformation of the circumferential end wall. In this example, the first coupling element 15 is therefore fitted into the second coupling element 51.

[0079] Thus, the sealing member 5 is retained in the cavity 6 by these two coupling elements 15 and 51 in both axial directions. The sealing member 5 therefore has its downstream 54d and upstream 54c surfaces free, that is to say in the flow stream of the machine. This embodiment makes it possible to have a blade 1 without walls axially closing the cavity 6. According to this embodiment, the blade can thus be more easily manufactured from Ceramic Matrix Composite CMC. The sealing member can be metallic.

[0080] The blade 1 further comprises a blade 17 extending radially from the platform 16 opposite the stilt 14.

[0081] Figures 7 and 8 each represent a different three-dimensional view of a portion of disk 3, at least one blade 1 and at least one sealing element 5', of a rotating assembly of a turbomachine according to an example of the second embodiment. In particular, Figure 7 represents a single blade 1' and a single sealing member 5', while Figure 8 represents the disk 3 with three blades 1' and three sealing members 5'. Figure 9 schematically represents a section AA of Figure 8.

[0082] Elements designated by a reference including an apostrophe “'” are different from the first example of this embodiment. Elements having the same reference are therefore substantially identical.

[0083] Figures 7 and 8 are a three-dimensional view seen from the downstream side. We can therefore see the downstream surface 54d' and the axial end edges 14d of the stilt 14' of each blade 1'.

[0084] Furthermore, the foot 13 of each blade 1 can be seen housed in a cell 30 formed between two teeth 31.

[0085] The blade 1' of this second example of this embodiment is different from the blade 1 of the first example of this embodiment in that the coupling elements 15' is female, here forming a housing for receiving the other coupling element, in this case it is a non-through hole. The stilt 14' is therefore different from that of the first embodiment in that the female coupling elements 15' is a hole which extends from the first circumferential end surface 14a towards the inside of the stilt 14', i.e. towards its second circumferential end surface 14b.

[0086] The sealing member 5' of this second example of this embodiment is therefore different from the sealing member 5 of the first example of this embodiment in that the second coupling element 51' is a protrusion projecting from the first circumferential end surface 54a forming a protrusion towards the blade 1'. The second coupling element 51' of each sealing member 5' is therefore housed in the female coupling element 15' extending from the first circumferential end surface 14a of Péchasse 14 of each corresponding blade 1', as can be seen in the circle shown in the section AA of figure 9. We can, in addition, see the inter-platform clearance j between the two platforms 16 in this figure 9.

[0087] Furthermore, the overall shape of this sealing member 5' has a blade shape and is different from that of the first example which is closer to a parallelepiped shape. However, the first and second circumferential end surfaces 54a and 54b are, as in the first example, in contact respectively with the first and second circumferential end surfaces 14a, 14b of two neighboring blades 1'. Indeed, in these different examples of these embodiments, the faces 54a and 54b of the sealing member 5, 5' are an imprint of the faces 14a and 14b of the stilts 14 of the blades 1.

[0088] In Figure 8, it can also be seen that as in the first example, in this second example, the radially external end surface 56a of each sealing member 5' is in contact with the internal surface of each platform 16.

[0089] Furthermore, as in the first example, in this second example, the upstream and downstream surfaces of each sealing member 5' are free.

[0090] According to another embodiment not shown, the sealing member comprises more than a single coupling element, for example a third coupling element extending from the second circumferential end surface nested with a fourth coupling element extending from the second circumferential end face of the stilt.

[0091] Figure 10 represents a blade 1A of the rotating assembly of the turbomachine of a second embodiment, and Figure 11 represents a radial section of the blade 1A and a sealing member 5A of the rotating assembly of the turbomachine of the second embodiment.

[0092] Elements designated by a reference including a capital “A” are different from the first embodiment.

[0093] The blade 1A is identical to that of the first example of the first embodiment except that the platform 16A includes the first coupling element 15A (belonging to the Péchasse place in the first embodiment). The first coupling element 15A extends from the first inner surface 16Aa of the first circumferential end wall 164Aa. In this case, in this example of this second embodiment, the first element coupling element 15A is a female coupling element, like the second example of the first embodiment. The first coupling element 15A is a hole extending from the inner surface 16Aa in the first circumferential end wall 164Aa of the platform 16. The first coupling element 15A could also, according to another example, as in the first example of the first embodiment, be male, that is to say a protrusion projecting from the inner surface 16Aa.

[0094] The stilt 14A is therefore devoid in this example of this embodiment of a coupling element. In this example the first coupling element 15A is an opening, that is to say a hole passing through the first circumferential end wall 164Aa of the platform 16A.

[0095] The sealing member 5A is therefore also different from the first embodiment in that the second coupling element 51A extends from the radially outer end surface 56Aa. The second coupling element 51A is therefore a male coupling element fitted into the first coupling element 15A.

[0096] Furthermore, in this example of this embodiment, the platform 16A comprises an internal edge 160Aa radially distant from the internal surface 16Aa of the platform 16A, surrounding a recess 161 Aa. The internal edge 160Aa thus forms a step. A periphery of the radially external end surface 56Aa of the sealing gasket 5A is in contact with the internal edge 160Aa. Thus the recess 161Aa is formed between the portion surrounded by the periphery of the radially external end surface 56Aa and the internal surface 16Aa. Thus the recess is sealed by the periphery of the sealing member in contact with this internal edge 160Aa. This characteristic of this example can also be applied to the first embodiment.

[0097] Of course, according to another example, as in the first embodiment, the radially external end surface 56Aa can also be in contact with the internal surface 16Aa of the platform 16A.

[0098] In this example, the second coupling element 51A of the sealing member 5A therefore comprises a base 510A extending from the radially external end surface 56A towards the first internal surface 16Aa of the platform 16 in the recess 161Aa. The second coupling element 51A further comprises an anchor 511A extending at the end of the base 51OA opposite the radially external end surface 56A housed in the receiving housing formed by the first coupling element 15A. The anchor 511A comprises a shape corresponding to that of the receiving housing formed by the first coupling element 15A to hermetically seal it. In this example the base and the anchor have a different section but could have the same section. In this example, the male coupling element 51A has a T-shape, the horizontal portion of the T-shape of the male coupling element being the anchor 511A located in the female coupling element 15A and the vertical portion of the T-shape of the male coupling element 51A is the base 51OA extending from a wall of the blade or the sealing member to the horizontal portion of the T-shape.

[0099] According to another embodiment not shown, the blade comprises the first coupling element according to one of the embodiments and a third coupling element according to one of the embodiments on the second circumferential end surface of the stilt or on the second internal surface of the platform.

[0100] In the various embodiments, the sealing member therefore makes it possible to seal the inter-platform clearance J while being held axially in both directions between two circumferential end walls of the blade flange by its second coupling element complementary to the first coupling element of the blade located between the two axial end edges and distant from them.

[0101] According to another embodiment not shown, the blade is identical to one of the embodiments described except that Péchasse further comprises a single axial wall extending further from one of the circumferential end surfaces 14a, 14b axially closing in one direction the cavity 6 with another Péchasse wall of the neighboring blade. This makes it possible to limit leaks.

[0102] All the blades and all the sealing members of the rotating assembly of the turbomachine may comprise the characteristics of one of the examples of the different embodiments previously described. Each blade and each sealing member may be different from another blade and another sealing member respectively or may all be identical.

[0103] Unless otherwise specified, the same element appearing in different figures has a single reference.

Claims

CLAIMS

1. Rotating assembly of a turbomachine with an axis (X) of rotation comprising: - a disc (3) centered on the axis (X) which has at its peripheries alveoli (30) delimited circumferentially by teeth (31) of the disc (3), - blades (1, 1', 1A) mounted circumferentially adjacent each in a respective cell (30) of the disc (3), each blade (1, 1', 1A) comprising: o a root (13) mounted in a respective cell (30) of the disc (3), the root (13) having a shape configured to allow mounting of the root (13) in the respective cell (30) of the disc (3), o a stilt (14, 14', 14A) formed by a wall which extends radially with respect to the axis (X) towards the outside of the root (13), the wall of the stilt (14, 14', 14A) being delimited by a first circumferential end surface (14a, 14a'), a second circumferential end surface (14b) opposite the first end surface circumferential (14a, 14a') and two axial end edges (14c, 14d) opposite each other, o a platform (16, 16', 16A) which extends at the radially external end of Péchasse (14, 14', 14A) and which is located circumferentially end-to-end of another platform (16, 16',16A) of another circumferentially adjacent blade (1, 1', 1A), and o a blade (17) which extends radially outward from the platform (16, 16', 16A), - at least one sealing member (5, 5', 5A) mounted in a cavity (6) delimited on the one hand by the disc (3) and on the other hand by the stilts (14, 14', 14A) and the platforms (16, 16', 16A) of the blade (1, 1', 1A) and of the other blade (1, 1', 1A) circumferentially adjacent, - in which: o the platform (16A) or stilt (14, 14') of the blade (1, 1', 1A) comprises a first coupling element (15, 15', 15A) coupled by male-female interlocking with a second coupling element (51, 51', 51A) extending from a wall of the sealing member (5, 5', 5A) so as to retain the sealing member (5, 5', 5A) with respect to the cavity (6), axially in both directions while allowing the sealing member to be pressed by centrifugal force against the platforms of the two blades, o the sealing member further comprises an upstream surface and a downstream surface and in that the cavity is open axially at least on one downstream or upstream side on all respectively the downstream surface or upstream surface.

2. A rotary assembly according to the preceding claim, wherein the first coupling member (51', 51A) is a male coupling member inserted into a groove of the second coupling member (51', 51A), or the second coupling member (51', 51A) is a male coupling member inserted into a groove of the first coupling member (51', 51A).

3. A rotary assembly according to claim 2 wherein the male coupling member (51A) has a T-shape, the horizontal portion of the T-shape of the male coupling member (51A) being located in the female coupling member (15A) and the vertical portion of the T-shape of the male coupling member (51A) extending from a wall of the blade or sealing member to the horizontal portion of the T-shape.

4. A rotary assembly according to one of claims 2 or 3, wherein the male coupling element (15, 15') is a protrusion projecting from a surface of a wall of the blade (1) or of the sealing member (5', 5A) and the female coupling element (51, 51', 51A) is a housing for receiving the protrusion, the female coupling element (51, 51', 51A) extending from a surface of a wall respectively of the sealing member (5) or of the blade (1', 1A).

5. Rotary assembly according to the preceding claim, in which the second coupling element (51 ', 51 A) comprises a base (51 OA) extending from the surface of the wall of the blade (1), and an anchor (511 A) comprising the complementary shape of the housing forming the first coupling element (15A) by filling it.

6. A rotary assembly according to claim 4 or 5 wherein the receiving housing forming the female coupling element (15A) is a hole passing through the wall.

7. A rotary assembly according to one of claims 1 to 5, wherein the sealing member (5, 5') comprises a circumferential end surface (54a) against the first circumferential end surface (14a, 14a') of the stilt (14, 14'), the second coupling element (51, 51') extending from the circumferential end surface (54a) of the sealing member (5, 5') and the first coupling element (15, 15') extending from the first circumferential end surface (14a, 14a') of the stilt (14, 14').

8. A rotary assembly according to any preceding claim, wherein the sealing member (5, 5', 5A) is hollow.

9. Rotary assembly according to one of the preceding claims, in which the sealing member (5, 5', 5A) has a first and a second circumferential end wall (54a, 54b) which each have a shape complementary respectively to the first circumferential end surface (14a, 14a') of the flange (14) and to a second circumferential end surface (14b) of a flange of a circumferentially adjacent blade.

10. A rotary assembly according to the preceding claim, wherein the first and second circumferential end walls (54a, 54b) are curved.

11. A rotary assembly according to any preceding claim, wherein the sealing member (5, 5', 5A) comprises a radially outer end surface (56a, 56Aa), - the platform (16, 16', 16A) comprises a first and a second circumferential end edge (164a, 164Aa, 164b) each having respectively a first radially internal surface (16a, 16Aa) and a second radially internal surface (16b) each respectively delimiting the cavity (6) forming the housing of the sealing member (5, 5', 5A) and a cavity (6) forming a housing for a second sealing member (5, 5', 5A), the first radially internal surface (16a, 16Aa) and the second radially internal surface (16b) each being respectively opposite the radially external end surface (56a, 56Aa) of the sealing member (5, 5', 5A) and a radially external end surface (56a, 56Aa) of the second sealing member (5, 5', 5A), - an inter-platform clearance (J) is formed between the first circumferential end edge (164a, 164Aa) and the second circumferential end edge (164b) of a circumferentially adjacent blade (1), the radially external end surface (56a, 56Aa) of the sealing member (5, 5', 5A) extending radially under the inter-platform clearance (J).

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