EP0709549B1 - Bladed rotor especially for a turbomachine - Google Patents

Description

In turbo-machines, the blades of turbines or compressors are fixed, in known manner, to the periphery of a rotor disc and comprise traditionally under a platform, separated from it by a stilt, a bulb shaped like a dovetail, coming to be housed in a cell corresponding machined in the disc.

The stilt of section narrower than the bulb, located between stiffeners, the platforms and the bulb, form two cavities located on the side lower surface for one and upper side for the other.

The juxtaposition of the blades at the periphery of the disc, creates leaks of gas on the one hand between two adjacent platforms at the level of the vein, and, on the other hand between the stiffeners adjacent upstream and downstream of the rotor of the turbine. In addition, vibration problems exist, especially when the blades do not have heels at the top.

To address the problem of leaks, it is known to install in the cavities of particular devices, which can be hollow and made of sheet metal stamped; they can also be full; be made of metallic material or plastic; etc. However, these devices do not completely seal leaks, especially axial leaks at the stiffeners.

Indeed, these "devices", under the action of centrifugal force, are plate under the walls of the platforms and only plug the leak at level of the vein.

An example of a sealing device is illustrated by GB-A-2 217 104 where the downstream edge of each blade platform carries a sealing and descending element up to the rim flange of the disc, the adjacent edges of two neighboring elements being provided with a groove where a deformable wire is placed ensuring the seal.

To limit the amplitude of the vibrations of the blades of a turbo-machine during operation, it is known to use shock-absorbing devices vibrations. These devices can consist of the devices described previously; they can also be made with polymer masses glued under the platforms in the cavities. Another solution is to add additional parts, such as upstream and downstream flanges.

The present invention provides simple devices for close all leaks at this level and eliminate vibrations.

We know by FR-A-2 619 158 a set of a rotating disc and blades attached to the periphery of the disc, used in particular in the production of a turbo-machine, comprising: said disc mounted to rotate about an axis of rotation; a plurality of fixing housings, formed at the periphery of the disc; a plurality of blades each having a root capable of being received in one of said fixing housings, so as to carry out the fixing of dawn on the disc; each blade further comprising a platform having two axial edges, and a veil, called "stilt", connecting the root to the platform, however that two adjacent blades each have one of their edges axial arranged opposite, and adjacent to an axial edge of the other blade adjacent, the two said adjacent edges delimiting between them a first axial passage; each blade having two stiffeners which extend in planes substantially perpendicular to the axis of rotation, between the platform and root of dawn each on either side of the stilt, and delimited by two axial selves and which, in cooperation with the platform, the root and the stilt, delimit two cavities located on either side of the stilt, however that two adjacent blades each have one of their said cavities arranged in sight of a cavity of the other adjacent blade, the two said cavities arranged in sight constituting a housing common to the two said adjacent blades, a first sealing device being placed inside said common housing by having a first sealing face arranged in look of said first axial passage and being held therein, so as to achieve the closure of the first axial passage. According to the invention the stiffeners of two adjacent blades are themselves adjacent two by two in each having an axial edge adjacent to an axial edge defining the other adjacent stiffener and a second radial passage is formed between the two said adjacent axial selvedges, and a second sealing device is placed inside said common housing by having a second sealing face disposed opposite said second radial passage and being held there, and, having also a thrust face, which is oblique to the radial direction of the centrifugal force and which is supported on a reaction face in the pushing direction axially said second sealing face towards the second radial passage of so as to close the second radial passage.

• selon une première réalisation un organe d'étanchéité est contenu dans ledit logement commun qu'il emplit sensiblement dans sa totalité, supporte lesdites première et deuxième faces d'étanchéité, et comporte un évidement, dont une des faces est constituée par ladite face oblique, et qui contient une masselotte mobile, munie de ladite face de réaction, ladite masselotte possédant en outre une fonction d'amortissement des vibrations éventuelles ;
• selon une deuxième réalisation, un organe d'étanchéité est contenu dans ledit logement commun qu'il n'emplit que partiellement, supporte lesdites première et deuxième faces d'étanchéité ainsi que la face oblique, cependant qu'au moins un premier appendice, solidaire de l'aube, maintient l'organe d'étanchéité en une position dans laquelle les première et deuxième faces d'étanchéité sont disposées en regard desdits premier passage axial et deuxième passage radial, respectivement, une masselotte étant également contenue à l'intérieur dudit logement commun, étant munie de ladite face de réaction et possédant en outre une fonction d'amortissement des vibrations éventuelles ;
• l'ensemble comporte un deuxième appendice, qui est solidaire de l'aube et qui maintient la masselotte en une position dans laquelle la face de réaction est disposée à proximité de et/ou en contact avec la face oblique de l'organe d'étanchéité ;
• le deuxième appendice coopère, également, avec le premier appendice, au maintien de la position de l'organe d'étanchéité dans laquelle les première et deuxième faces d'étanchéité sont disposées en regard des premier passage axial et deuxième passage radial, respectivement ;
• l'organe d'étanchéité est constitué par un corps creux et possède une paroi, dont l'épaisseur, dans la zone de la face oblique, est supérieure à l'épaisseur dans les zones des première et deuxième faces d'étanchéité ;
• selon une troisième réalisation, l'ensemble comporte un organe d'étanchéité, contenu dans ledit logement commun, ayant une section radiale sensiblement conformée en un L, les faces externes du L constituant, respectivement, lesdites première et deuxième faces d'étanchéité, ledit organe d'étanchéité supportant en outre une protubérance munie de ladite face oblique de poussée, cependant qu'un premier appendice, solidaire de l'aube, supporte ladite face de réaction ;
• la protubérance possède une face de butée qui est disposée dans le prolongement de la face de réaction, en en étant angulairement décalée, et en formant par conséquence un dièdre avec la face de réaction, cependant que ledit dièdre est contenu, avec un jeu radial, dans un évidement de forme complémentaire, qui est ménagé dans ledit premier appendice et qui est muni d'une face de butée complémentaire disposée en regard de la face de butée de la protubérance;
• l'ensemble comporte un deuxième appendice, qui est solidaire de l'aube et qui constitue une butée de maintien de la protubérance à l'intérieur de l'évidement du premier appendice ;
• la protubérance est constituée par une pièce distincte de l'organe d'étanchéité, rendue solidaire de l'organe d'étanchéité par des moyens d'une fixation amovible ;
• ladite protubérance constitue en outre une masselotte ayant la fonction d'amortissement de vibrations éventuelles ;
• l'organe d'étanchéité est constitué par un corps creux ;
• selon une quatrième réalisation, l'ensemble comporte un organe d'étanchéité, qui est contenu dans ledit logement commun, qui possède une section radiale conformée sensiblement en un L, les faces externes du L constituant, respectivement, lesdites première et deuxième faces d'étanchéité, cependant que l'extrémité libre d'une première branche du L, qui supporte la première face d'étanchéité, supporte elle-même ladite face oblique et qu'une masselotte principale, également contenue à l'intérieur du logement commun, supporte ladite face de réaction ;
• une première desdites lisières axiales, appartenant à une première aube, présente une première face axiale principale de butée, qui s'étend généralement axialement, cependant que la deuxième lisière axiale, appartenant à une deuxième aube et délimitant, avec ladite première lisière axiale, ledit premier passage axial, présente une deuxième face axiale principale de poussée, qui est oblique par rapport à ladite première face axiale principale de butée, que ladite première branche du L de l'organe d'étanchéité comporte une première face axiale complémentaire de butée, qui est susceptible de présenter la même orientation que, et d'être en appui sur la première face axiale principale de butée, ladite première branche du L de l'organe d'étanchéité comportant également une deuxième face axiale complémentaire de poussée, susceptible d'être en contact de glissement avec la deuxième face axiale principale de poussée, de manière que, sous l'effet de la force centrifuge, ladite deuxième face axiale complémentaire de poussée, soit susceptible de glisser sur la deuxième face axiale principale de poussée dans le sens mettant en contact lesdites premières faces axiales complémentaire et principale de butée, lesdits contacts réalisant l'obturation dudit premier passage axial ;
• une première lisière radiale, appartenant à ladite première aube et définissant ledit deuxième passage radial, présente une première face radiale principale de butée, qui s'étend sensiblement radialement, cependant que la deuxième lisière axiale, appartenant à la deuxième aube et délimitant, avec ladite première lisière axiale, ledit deuxième passage radial, présente une deuxième face radiale principale d'appui, qui est décalée angulairement de sensiblement 90° par rapport à la première face radiale principale de butée, et que la deuxième branche du L de l'organe d'étanchéité comporte une première face radiale complémentaire de butée et une première face radiale complémentaire de poussée susceptible d'être placée en appui étanche sur les première face radiale principale de butée et deuxième face radiale principale d'appui, et de réaliser ainsi l'obturation dudit deuxième passage radial, concomitamment à la réalisation de l'obturation dudit premier passage axial ;
• la partie complémentaire de la première lisière axiale, sur laquelle l'organe d'étanchéité n'est pas en appui, présente une première face radiale principale de guidage, qui s'étend radialement, cependant que la partie complémentaire de ladite deuxième lisière axiale présente une deuxième face radiale principale de guidage, qui est décalée angulairement de sensiblement 90° par rapport à la première face radiale principale de guidage, et que ladite masselotte principale comporte des première et deuxième faces radiales complémentaires de guidage susceptibles d'être placées en appui de guidage sur lesdites première et deuxième faces radiales principales de guidage et de réaliser le guidage par glissement de ladite masselotte sur les parties complémentaires desdites première et deuxième lisières axiales ;
• l'ensemble comporte des appendices de maintien en position, solidaires chacun d'une des aubes, de l'organe d'étanchéité et de la masselotte principale ;
• l'organe d'étanchéité est constitué par un corps massif formant une masselotte complémentaire ;
• selon une cinquième réalisation, l'ensemble comporte un organe d'étanchéité constitué par une plaquette, qui est distincte desdites aubes, qui est contenue dans ledit logement commun, qui, d'une part, possède une face d'étanchéité mise en appui étanche sur chacune des parties de faces internes de deux raidisseurs adjacents, délimitant ledit deuxième passage radial, d'autre part, supporte ladite face oblique de poussée, et, qui est maintenue en appui sur lesdites parties de faces internes des raidisseurs adjacents par l'intermédiaire, d'une part, de premiers appendices, solidaires des aubes, pour le maintien dans les sens perpendiculaires au plan dudit deuxième passage radial, d'autre part, dans le sens radial, d'un deuxième appendice qui est également solidaire d'une aube et qui supporte ladite face de réaction ;
• lesdites parties des faces internes des deux raidisseurs adjacents sont planes et sensiblement coplanaires, cependant que la face d'étanchéité de ladite plaquette est également plane ;
• l'un desdits premiers appendices et ladite plaquette sont munis, chacun, de bossages complémentaires formant coins, qui coopèrent à l'immobilisation de la plaquette par rapport à l'une des aubes.

The following advantageous arrangements are also preferably adopted:

• according to a first embodiment, a sealing member is contained in said common housing which it fills substantially in its entirety, supports said first and second sealing faces, and comprises a recess, one of the faces of which is constituted by said oblique face, and which contains a movable flyweight, provided with said reaction face, said flyweight further having a function of damping any vibrations;
• according to a second embodiment, a sealing member is contained in said common housing which it only partially fills, supports said first and second sealing faces as well as the oblique face, while at least one first appendage, integral of the blade, maintains the sealing member in a position in which the first and second sealing faces are arranged opposite said first axial passage and second radial passage, respectively, a counterweight being also contained inside said common housing, being provided with said reaction face and further having a function of damping any vibrations;
• the assembly includes a second appendage, which is integral with the blade and which maintains the counterweight in a position in which the reaction face is disposed close to and / or in contact with the oblique face of the sealing member ;
• the second appendix also cooperates with the first appendage in maintaining the position of the sealing member in which the first and second sealing faces are arranged opposite the first axial passage and second radial passage, respectively;
• the sealing member is constituted by a hollow body and has a wall, the thickness of which, in the region of the oblique face, is greater than the thickness in the regions of the first and second sealing faces;
• according to a third embodiment, the assembly comprises a sealing member, contained in said common housing, having a radial section substantially shaped as an L, the external faces of the L constituting, respectively, said first and second sealing faces, said sealing member further supporting a protuberance provided with said oblique thrust face, while a first appendage, integral with the blade, supports said reaction face;
• the protuberance has an abutment face which is arranged in the extension of the reaction face, by being angularly offset therefrom, and consequently forming a dihedral with the reaction face, while said dihedral is contained, with a radial clearance, in a recess of complementary shape, which is formed in said first appendage and which is provided with a complementary abutment face disposed opposite the abutment face of the protuberance;
• the assembly includes a second appendage, which is integral with the blade and which constitutes a stop for maintaining the protuberance inside the recess of the first appendage;
• the protuberance consists of a separate part of the sealing member, made integral with the sealing member by means of a removable attachment;
• said protuberance further constitutes a counterweight having the function of damping any vibrations;
• the sealing member is constituted by a hollow body;
• according to a fourth embodiment, the assembly comprises a sealing member, which is contained in said common housing, which has a radial section shaped substantially in an L, the external faces of the L constituting, respectively, said first and second faces of sealing, however that the free end of a first branch of the L, which supports the first sealing face, itself supports said oblique face and that a main counterweight, also contained inside the common housing, supports said reaction face;
• a first of said axial edges, belonging to a first blade, has a first main axial abutment face, which generally extends axially, while the second axial edge, belonging to a second blade and delimiting, with said first axial edge, said first axial passage, has a second main axial thrust face, which is oblique with respect to said first main axial abutment face, that said first branch of the L of the sealing member has a first complementary axial face of abutment, which is likely to have the same orientation as, and to be supported on the first main axial abutment face, said first branch of the L of the sealing member also comprising a second complementary axial face of thrust, capable of being in sliding contact with the second main axial thrust face, so that, under the effect of the centrifugal force, said second complementary axial face of thrust, is capable of sliding on the second main axial face of thrust in the direction bringing said first complementary and main axial faces of abutment, said contacts realizing said first axial passage ;
• a first radial edge, belonging to said first blade and defining said second radial passage, has a first main radial abutment face, which extends substantially radially, while the second axial edge, belonging to the second blade and delimiting, with said first axial selvedge, said second radial passage, has a second main radial bearing face, which is angularly offset by substantially 90 ° relative to the first main radial abutment face, and that the second branch of L of the member d sealing comprises a first complementary radial face of abutment and a first complementary radial face of thrust capable of being placed in sealed abutment on the first main radial face of abutment and second main radial face of support, and thus achieving obturation of said second radial passage, concomitantly with the obturation of said first axial passage;
• the complementary part of the first axial selvedge, on which the sealing member is not supported, has a first main radial guiding face, which extends radially, while the complementary part of said second axial selvedge has a second main radial guiding face, which is angularly offset by substantially 90 ° relative to the first main guiding radial face, and that said main counterweight has first and second complementary radial guiding faces capable of being placed in abutment guiding on said first and second main guiding radial faces and carrying out the sliding guidance of said counterweight on the complementary parts of said first and second axial selves;
• the assembly includes appendages for holding in position, each secured to one of the blades, to the sealing member and to the main counterweight;
• the sealing member is constituted by a solid body forming a complementary flyweight;
• according to a fifth embodiment, the assembly comprises a sealing member constituted by a plate, which is distinct from said blades, which is contained in said common housing, which, on the one hand, has a sealing face which is placed in leaktight support on each of the parts of the internal faces of two adjacent stiffeners, delimiting said second radial passage, on the other hand, supports said oblique thrust face, and which is held in abutment on said parts of internal faces of the adjacent stiffeners by means of , on the one hand, first appendages, integral with the blades, for maintaining in the directions perpendicular to the plane of said second radial passage, on the other hand, in the radial direction, with a second appendage which is also integral with a blade and which supports said reaction face;
• said parts of the internal faces of the two adjacent stiffeners are planar and substantially coplanar, while the sealing face of said plate is also planar;
• one of said first appendages and said plate are each provided with complementary bosses forming corners, which cooperate in immobilizing the plate relative to one of the blades.

The main advantage of the assemblies according to the invention lies in the simplicity of the achievements and their effectiveness.

The invention will be better understood, and secondary characteristics and their advantages will become apparent during the description of achievements given below for exemple.

It is understood that the description and the drawings are given only for indicative and not limiting.

• la figure 1 est une coupe par un plan radial, contenant l'axe de rotation, d'une première réalisation d'un ensemble conforme à l'invention, suivant I-I de la figure 2 ;
• la figure 2 est une coupe suivant II-II de la figure 1 ;
• la figure 3 est une coupe suivant III-III de la figure 2 ;
• la figure 4 est une coupe, analogue à celle de la figure 1, d'une deuxième réalisation d'un ensemble conforme à l'invention ;
• la figure 5 est une coupe suivant V-V de la figure 4 ;
• la figure 6 est une coupe, analogue à celle de la figure 1, d'une troisième réalisation d'un ensemble conforme à l'invention suivant VI-VI de la figure 7 ;
• la figure 7 est une coupe suivant VII-VII de la figure 6 ;
• la figure 8 est une coupe, analogue à celle de la figure 1, d'une quatrième réalisation d'un ensemble conforme à l'invention ;
• la figure 9 est une coupe transversale, par un plan perpendiculaire à l'axe de rotation, selon IX-IX de la figure 8 ;
• la figure 10 est une coupe, analogue à celle de la figure 1, d'une cinquième réalisation, variante de réalisation de la figure 8, également conforme à l'invention ;
• la figure 11 est une section suivant XI-XI de la figure 10 ;
• la figure 12 est une coupe, analogue à celle de la figure 1, d'une sixième réalisation d'un ensemble conforme à l'invention ;
• la figure 13 est une coupe suivant XIII-XIII de la figure 12 ; et
• la figure 14 est une section suivant XIV-XIV de la figure 13.

Reference will be made to the accompanying drawings, in which:

• Figure 1 is a section through a radial plane, containing the axis of rotation, of a first embodiment of an assembly according to the invention, along II of Figure 2;
• Figure 2 is a section along II-II of Figure 1;
• Figure 3 is a section along III-III of Figure 2;
• Figure 4 is a section, similar to that of Figure 1, of a second embodiment of an assembly according to the invention;
• Figure 5 is a section along VV of Figure 4;
• Figure 6 is a section similar to that of Figure 1, of a third embodiment of an assembly according to the invention according to VI-VI of Figure 7;
• Figure 7 is a section along VII-VII of Figure 6;
• Figure 8 is a section, similar to that of Figure 1, of a fourth embodiment of an assembly according to the invention;
• Figure 9 is a cross section through a plane perpendicular to the axis of rotation, according to IX-IX of Figure 8;
• Figure 10 is a section, similar to that of Figure 1, of a fifth embodiment, alternative embodiment of Figure 8, also according to the invention;
• Figure 11 is a section along XI-XI of Figure 10;
• Figure 12 is a section, similar to that of Figure 1, of a sixth embodiment of an assembly according to the invention;
• Figure 13 is a section along XIII-XIII of Figure 12; and
• Figure 14 is a section along XIV-XIV of Figure 13.

The first embodiment according to the invention, shown on the Figures 1 to 3, includes a disc 1, of axis of rotation 2, provided at its periphery external notches 3 each capable of receiving the root 4 of a blade 5 of turbo-machine, said root 4 having a complementary shape - tail dovetail or the like - of that of the notch 3, so as to achieve the fixing of dawn on the disc.

Each blade 5, further comprises a platform 6 having two axial selvedges 6A, substantially parallel to the axis 2, and a veil 7, called "stilt", connecting the root 4 to the platform 6, while two blades adjacent each have one of their axial edges 6A disposed opposite, and adjacent to an axial edge 6A of the other adjacent blade, the two said edges adjacent areas delimiting between them a first axial passage 8.

Each blade has two stiffeners 9 which extend in planes substantially perpendicular to the axis of rotation 2, between the platform 6 and the root 4 of dawn, each on each side of stilt 7, and delimited by two radial edges 9A and which, in cooperation with the platform 6, the root 4 and stilt 7, delimit two cavities 10 located on either side of stilt 7, however that two adjacent blades each have one of their said cavities arranged opposite a cavity of the other adjacent blade, the two said cavities 10 arranged opposite constituting a common housing 10 to the two said blades adjacent, and that the stiffeners 9 of two adjacent blades are themselves adjacent two by two each having a radial edge 9A adjacent to a radial edge 9A defining the other adjacent stiffener, a second radial passage 11 being formed between the two said adjacent radial edges 9A.

A first sealing device 12 is placed inside said common housing 10 by having a first sealing face 12A arranged in look of said first axial passage 8 and being held there (FR), so as to close the first axial passage 8. A second device seal 12 is placed inside said common housing 10 having a second sealing face 12B disposed opposite said second radial passage 11 and being held there (13-FR), and, also having a thrust face 14, which is oblique to the radial direction R of the centrifugal force FR and which is supported on a reaction face 15 in the direction axially pushing said second sealing face 12B towards the second radial passage 11 so as to close the second radial passage 11.

The sealing member 12 is contained in said common housing 10 that it fills substantially in its entirety, is unique and supports said first (12A) and second (12B) sealing faces, and has a recess 16, of which one of the faces is constituted by said oblique thrust face 14, and which contains a movable counterweight 13 provided with said reaction face 15, said counterweight 13 additionally having a function of damping any vibrations.

According to the second embodiment of Figures 4 and 5, the sealing member 112 contained in said common housing (10) only fills it partially, supports said first (112A) and second (112B) sealing faces, as well as the oblique push face 114, while at least one first appendage 18, integral with one of the adjacent blades 5, maintains the sealing member 112 in one position in which the first (112A) and second (112B) sealing faces are arranged opposite said first axial passage 8 and second passage radial 11, respectively, a counterweight 113 also being contained at the interior of said common housing 10, being provided with said reaction face 115 and additionally having a function of damping any vibrations.

In this second embodiment, a second appendage 19, integral one of the adjacent blades 5, maintains the counterweight 113 in a position in which the reaction face 115 is arranged near and / or in contact with the oblique thrust face 114 of the sealing member 112.

This second appendix 19 also cooperates with the first appendix 18, maintaining the position of the sealing member 112 in which the first (112A) and second (112B) sealing faces are arranged in look of the first axial passage 8 and second radial passage 11, respectively.

In either of the two embodiments described, the sealing member (12; 112) consists of a hollow body and has a wall, the thickness of which (E14; E114), in the region of the oblique thrust face (14; 114), is higher to the thickness (E12A, E12B; E112A, E112B) in the zones of the first (12A; 112A) and second (12B; 112B) sealing faces.

According to a third embodiment (Figures 6 and 7), the sealing member (212) contained in said common housing 10 has a radial section substantially shaped as an L with two branches 22A, 22B, the external faces 212A, 212B of said branches of L constituting, respectively, the first (212A) and second (212B) sealing faces, said sealing member further supporting a protrusion 220 provided with said oblique push face 214, however that a first appendage 218 integral with one of the adjacent blades 5, supports said reaction face 215.

The protrusion 220 has a stop face 221 which is arranged in the extension of the thrust face 214, by being angularly offset therefrom, and consequently forming a dihedral with the thrust face, while said dihedral is contained, with a radial clearance, in a recess 222 of shape complementary, which is provided in said first appendix 218 and which is provided an additional abutment face 223 disposed opposite the abutment face 221 of the protuberance 220.

A second appendix 219 is integral with the dawn and constitutes a retaining stop for the protrusion 220 inside the recess 222 of the first appendix 218. The protuberance 220 is constituted by a separate part of the sealing member 212, made integral with the sealing member 212 by means 223 of a removable attachment, such as a clip secured to the branch 22B of the sealing member 212. Said protuberance 220, further constitutes a counterweight having the function of damping any vibrations. Finally, the sealing member 212 consists of a hollow body.

According to a fourth embodiment, represented by FIGS. 8 and 9, the sealing member 312 contained in said common housing 10 has a radial section substantially shaped as an L with two branches 32A, 32B, the external faces 312A, 312B of the two branches 32A, 32B of the constituent L, respectively, first (312A) and second (312B) sealing faces, however that the free end of a first branch 32A of the L, which supports the first sealing face 312A, itself supports said oblique face of thrust 314 and that a main counterweight 313, also contained inside of the common housing 10, supports said reaction face 315.

A first of said axial edges, belonging to a first blade 5, has a first main axial abutment face 306A, which generally extends axially, however that the second axial selvedge, belonging to the dawn adjacent 5 and delimiting, with said first axial selvedge, said first passage axial 8, has a second main axial thrust face 306B, which is oblique to said first main axial abutment face 306A, that said first branch 32A of L of the sealing member 312 comprises a first complementary axial face of stop 324A, which is capable of present the same orientation as, and to be supported on the first axial face main stop 306A, said first branch 32A of L of the member sealing 312 also comprising a second complementary axial face thrust 325A likely to be in sliding contact with the second face main axial thrust 306B, so that under the effect of centrifugal force FR, said second complementary axial face of thrust 325A either likely to slide on the second main axial thrust face 306B in the direction bringing said first complementary axial faces into contact (324A) and main (306A) stop, said contacts closing said first axial passage 8.

The fifth embodiment shown in Figures 10 and 11 is close of the fourth embodiment and comprises, in particular a sealing member 412 shaped as an L with two branches 42A, 42B. The aforementioned provisions, which relate to the conformation of the first branch 32A of L, can be adopted with regard to the first branch 42A of the sealing member 412 of this achievement. This also includes a first radial edge, belonging to said first blade 5 and defining said second radial passage 11, which has a first main radial abutment face 405A, which extends substantially radially, however that a second radial edge belonging to the adjacent dawn 5 and delimiting, with said first radial edge, said second radial passage 11, has a second main radial support face 405B, which is angularly offset by substantially 90 ° relative to the first face main radial stop 405A, and that the second branch 42B of L of the member seal 412 has a first complementary radial face of stop 426A and a first complementary radial face of thrust 426B capable to be placed in sealed support on the first main radial abutment face 405A and second main radial face of support 405B, respectively, and of thus closing off said second radial passage 11, concomitantly with the closing said first axial passage 8 by the first branch 42A of the sealing member 412.

Both in the fourth and in the fifth embodiment, the the following provision is advantageously adopted. The complementary part of the first radial selvedge, on which the sealing member 412 is not supported, has a first main guide radial face 405C, which extends radially, however that the complementary part of said second selvedge radial has a second main radial guiding face 405D, which is angularly offset by substantially 90 ° relative to the first radial face first (413C) and second (413D) complementary radial guide faces likely to be placed in guide support on said first (405C) and second (405D) main radial guide faces, respectively, and carry out the sliding guide of said counterweight 413 on the parts complementary to said first and second radial edges. So similar to the embodiment of FIGS. 8 and 9, the end of the branch 42A supports the oblique thrust face 414, which cooperates with the reaction face 415 of the counterweight 413.

Analogously to the provisions of the second embodiment of Figures 4 and 5, and, the third embodiment of Figures 6 and 7, the embodiments of Figures 8 and 9, and, 10 and 11 may include appendages of holding the sealing members and the weights in position. The disposition corresponding is shown in Figure 10 relating to the fifth embodiment. Appendages 418, 419 for holding in position are provided, each integral from one of the adjacent blades 5, and hold the sealing member 412 and the main counterweight 413. Furthermore, the sealing member 312; 412 is advantageously constituted itself by a massive body forming a counterweight complementary.

In the sixth embodiment of Figures 12, 13 and 14, the element sealing comprises two distinct elements: an elongated profile 512, one of which face 512A is applied in sealed support on the internal faces 506A of the platforms 6 of adjacent blades 5, pins 527, integral with the blades, ensuring the maintaining the profile 512 in watertight support along the selvedges delimiting the first axial passage 8. and, a plate 528. This plate 528 is distinct from said vanes 5, is contained in said common housing 10, on the one hand has a face seal 528A sealingly supported on each of the parts of internal faces 9B of two adjacent stiffeners 9 delimiting said second radial passage 11, and on the other hand, supports said oblique thrust face 514, and is held in abutment on said internal face portions of the adjacent stiffeners through, on the one hand, the first appendages 529, 531, integral with the blades 5, for the holding in the directions perpendicular to the plane of said second radial passage 11, on the other hand, in the radial direction (R), of a second appendix 530 which is also integral with a blade and which supports said reaction face 515. The parts of the internal faces 9B of the two adjacent stiffeners 9 are planar and substantially coplanar, however that the sealing face 528A of said plate 528 is also flat. Finally, some (531) of said first appendages and said plate 528 are each provided with bosses complementary 532, 533 forming corners, which cooperate in immobilizing the plate 528 relative to one of the blades 5.

The operations of the various realizations are similar, as this is set out below.

First, when the disc 1 is rotated, the force centrifugal FR, of radial direction, acts on the counterweight 13; 113; 223; 313; 413; or 528, so that the reaction force transmitted by the reaction face 15; 115; 215; 315; 415; 515 to the oblique thrust face 14; 114; 214; 314; 414; 514 is an axial component sealingly pressing the face 12B, 112B; 212B; 312B; 426B; 528A on the radial edges delimiting the second pass radial 11, thereby eliminating gas leaks through the various passages radial 11.

Leaks through the various axial passages 8 are also eliminated thanks to the radial component of the centrifugal force which presses on the selvedges delimiting the first axial passages 8 the faces 12A; 112A; 212A; 312A; 412A; 512A of the sealing members.

When the sealing member 12 substantially fills the housing 10 (Figures 1 to 3), the counterweight 13 and the sealing member 12 are held in position without the aid of support appendages. Most of them in other cases (Figures 4 and 5; 6 and 7; 10 and 11; 12 to 14), the appendages that were provided permanently maintain the sealing faces 112A, 112B; 212A, 212B; 412A, 426B; 512A, 528A opposite the edges of the axial passages 8 and radials 11, ready to be placed in watertight support under the effect of centrifugal force FR.

In the case of the embodiment of FIGS. 8 and 9, a small projection belonging to the disc 1 maintains the sealing member 312 in position, in cooperation with the flyweight 313.

The locks in the sealed position by the effect of oblique corners are in besides very effective.

Finally, not only is the seal obtained, but also the vibrations are attenuated thanks to the weights which have been provided.

The provisions of Figures 8 and 9, and, 10 and 11 further allow ensure sealing even in the case of adjacent blade sealing faces not coplanar.

Claims (21)

1. Assembly of a rotary disc and of blades fixed to the periphery of the disc, used especially in producing a turbomachine, comprising:

   the said disc (1) mounted so that it can rotate about an axis of rotation (2);

   a number of attachment housings (3) formed at the periphery of the disc (1);

   a number of blades (5) each having a root (4) which is housed in one of the said attachment housings (3), so as to attach the blade to the disc;

   each blade (5) further comprising a platform (6) exhibiting two axial selvedges (6A) and a web (7), termed "pole", connecting the root to the platform, while two adjacent blades each have one of their axial selvedges (6A) arranged opposite and adjacent to an axial selvedge (6A) of the other adjacent blade, the two said adjacent selvedges delimiting a first axial passage (8) between them;

   each blade comprising two stiffeners (9) which extend in planes approximately perpendicular to the axis of rotation (2), between the platform (6) and the root (4) of the blade, one on each side of the pole (7), and delimited by two axial selvedges (9A) and which, in conjunction with the platform, the root and the pole, delimit two cavities situated one on either side of the pole, while two adjacent blades each have one of their said cavities arranged opposite a cavity of the other adjacent blade, the two said cavities arranged opposite each other constituting a housing (10) common to the two said adjacent blades (5), a common housing (10), having a first sealing face (12A) arranged opposite the said first axial passage (8) and being held therein so as to seal the first axial passage (8), characterized in that the stiffeners (9) of two adjacent blades are themselves adjacent in pairs, each having an axial selvedge (9A) adjacent to an axial selvedge (9A) delimiting the other adjacent stiffener, a second radial passage (11) being formed respectively between the two said adjacent axial selvedges; and in that a second sealing device (12) is placed inside the said common housing (10), having a second sealing face (12B) arranged opposite one of the second radial passages (11) and being held therein, and, also having a thrust face (14) which is oblique with respect to the radial direction (R) of the centrifugal force (FR) and which bears against a reaction face (15) in the direction axially thrusting the said second sealing face (12B) towards the second radial passage (11) so as to seal the second radial passage (11).
2. Assembly according to Claim 1, characterized in that a sealing member (12) is contained in the said common housing (10) which it fills almost completely, supports the said first (12A) and second (12B) sealing faces and has a recess (16), one (14) of the faces of which consists of the said oblique face (14), and which contains a moving flyweight (13) equipped with the said reaction face (15), the said flyweight (13) also fulfilling a function of damping any vibrations there may be.
3. Assembly according to Claim 1, characterized in that a sealing member (112) is contained in the said common housing (10) which it fills only partially, supports the said first (112A) and second (112B) sealing faces and the oblique face (114), while at least one first appendage (18), secured to the blade (5), keeps the sealing member (12) in a position in which the first (12A) and second (12B) sealing faces and second radial passage (11), respectively, a flyweight (113) also being contained inside the said common housing (10), being equipped with the said reaction face (115), and also fulfilling a function of damping any vibrations there may be.
4. Assembly according to Claim 3, characterized in that it comprises a second appendage (19), which is secured to the blade (5) and which keeps the flyweight (113) in a position in which the reaction face (115) is arranged close to and/or in contact with the oblique face (114) of the sealing member (112).
5. Assembly according to Claim 4, characterized in that the second appendage (19) also interacts with the first appendage (18) in keeping the sealing member (112) in a position in which the first (112A) and second (112B) sealing faces are arranged opposite the first axial passage (8) and second radial passage (11), respectively.
6. Assembly according to any one of Claims 2 to 5, characterized in that the sealing member consists of a hollow body and has a wall (12; 112), of which the thickness (E14; E114) in the region of the oblique face (14; 114) exceeds the thickness (E12A, E12B; E112A, E112B) in the regions of the first (12A; 112A) and second (12B; 112B) sealing faces.
7. Assembly according to Claim 1, characterized in that it comprises a sealing member (212) contained in the said common housing (10), having an approximately L-shaped radial section (22A, 22B), the outer faces (212A, 212B) of the L respectively constituting the said first (212A) and second (212B) sealing faces, the said sealing member (212) further supporting a protrusion (220) equipped with the said oblique thrust face (214), while a first appendage (218) secured to the blade (5) supports the said reaction face (215).
8. Assembly according to Claim 7, characterized in that the protrusion (220) has a stop face (221) which is arranged in line with the reaction face (215), being angularly offset therefrom, and therefore forming a dihedron with the reaction face (215) while the said dihedron is contained, with radial clearance, in a recess (222) of complementary shape which is formed in the said first appendage (218) and which is equipped with a complementary stop face (223) arranged opposite the stop face (221) of the protrusion (220).
9. Assembly according to Claim 8, characterized in that it comprises a second appendage (219) which is secured to the blade (5) and which constitutes a stop for keeping the protrusion (220) inside the recess (222) of the first appendage (218).
10. Assembly according to any one of Claims 7 to 9, characterized in that the protrusion (220) consists of a part that is separate from the sealing member (212) and is secured to the sealing member (212) by means (223) of a removable attachment.
11. Assembly according to any one of Claims 7 to 10, characterized in that the said protrusion (220) further constitutes a flyweight having the function of damping any vibrations there may be.
12. Assembly according to any one of Claims 7 to 11, characterized in that the sealing member (212) consists of a hollow body.
13. Assembly according to Claim 1, characterized in that it comprises a sealing member (312) which is contained in the said common housing (10) and has an approximately L-shaped radial section (32A-32B), the outer faces (312A, 312B) of the L respectively constituting the said first (312A) and second (312B) sealing faces, while the free end of a first branch (32A) of the L, which supports the first sealing face (312A), itself supports the said oblique face (314), and a main flyweight (313), also contained inside the common housing (10), supports the said reaction face (315).
14. Assembly according to Claim 13, characterized in that a first of the said axial selvedges, belonging to a first blade (5), has a first main axial stop face (306A) which extends generally axially, while the second axial selvedge, belonging to a second blade (5), and delimiting the said first axial passage (8) with the said first axial selvedge, has a second main axial thrust face (306B) which is oblique with respect to the said first main axial stop face (306A), the said first branch (32A) of the L of the sealing member (312) comprises a first complementary axial stop face (324A) which has the same orientation as and rests against the first main axial stop face (306A), the said first branch (32A) of the L of the sealing member (312) also comprising a second complementary axial thrust face (325A) which is in sliding contact with the second main axial thrust face (306B) so that under the effect of centrifugal force (FR), the said second complementary axial thrust face (325A) slides along the second main axial thrust face (306B) in the direction that brings the said first complementary (324A) and main (306A) axial stop faces into contact, the said contacts sealing the said first axial passage (8).
15. Assembly according to Claim 14, characterized in that a first axial selvedge belonging to the said first blade (5) and defining the said second radial passage (11), has a first main radial stop face (405A), which extends approximately radially, while the second axial selvedge belonging to the second blade (5) and delimiting the said second radial passage (11) with the said first axial selvedge, has a second main radial bearing face (405B) which is angularly offset by approximately 90° with respect to the first main radial stop face (405A), and the second branch (42B) of the L of the sealing member (412) comprises a first complementary radial stop face (426A) and a first complementary radial thrust face (426B) which are placed bearing in a sealed manner against the first main radial stop face and second main radial bearing face (405B) and thus seal the said second radial passage (11) at the same time as sealing the said first axial passage (8).
16. Assembly according to any one of Claims 13 to 15, characterized in that the complementary part of the first axial selvedge, against which the sealing member (412) does not bear, has a first main radial guide face (405C) which extends radially, while the complementary part of the said second axial selvedge has a second main radial guide face (405D) which is angularly offset by approximately 90° with respect to the first main radial guide face (405C), and the said main flyweight (413) has first (413C) and second (413D) complementary radial guide faces which are placed bearing for guidance against the said first (405C) and second (405D) main radial guide faces and guide the said flyweight (413) in sliding over the complementary parts of the said first and second axial selvedges.
17. Assembly according to any one of Claims 13 to 16, characterized in that it comprises appendages (418, 419), each secured to one of the blades (5), for holding the sealing member (412) and the main flyweight (413) in position.
18. Assembly according to any one of Claims 13 to 17, characterized in that the sealing member (312; 412) consists of a solid body forming an additional flyweight.
19. Assembly according to Claim 1, characterized in that it comprises a sealing member consisting of a platelet (528), which is distinct from the said blades (5) and is contained in the said common housing (10) and, on the one hand, has a sealing face (528A) bearing in sealed fashion against each of the inner-face parts (9B) of two adjacent stiffeners (9) delimiting the said second radial passage (11) and, on the other hand, supports the said oblique thrust face (514), and which is kept bearing against the said inner-face parts of the adjacent stiffeners, on the one hand, by first appendages (529, 531) secured to the blades (5), for holding it in directions perpendicular to the plane of the said second radial passage (11) and, on the other hand, in the radial direction (R), by a second appendage (530) which is also secured to a blade (5) and which supports the said reaction face (515).
20. Assembly according to Claim 19, characterized in that the said inner-face parts (9B) of the two adjacent stiffeners (9) are flat and approximately coplanar, while the sealing face (528A) of the said platelet (528) is also flat.
21. Assembly according to either one of Claims 19 and 20, characterized in that one (531) of the said first appendages and the said platelet (528) are each equipped with complementary bosses (532, 533) forming wedges, which play a part in immobilizing the platelet (528) with respect to one of the blades (5).

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