TURBINE ASSEMBLY COMPRISING A CROWN EQUIPPED WITH BLADE SECTORS

Abstract

TITLE: TURBINE ASSEMBLY COMPRISING AT LEAST ONE RING OF BLADES PROVIDED WITH BLADE SECTORS One aspect of the invention relates to a turbine assembly (10) comprising a ring of blades (12) of axis X comprising adjacent sectors (100) each provided with a sealed platform (110-1, 110-2) comprising first and second connecting edges (112, 114), the first edge of the platform of a sector being opposite and spaced from the second edge of the platform of the adjacent sector. Each edge comprises a housing surface (116) and a recess (118) according to which the housing surface and the recess of the first edge of the platform of a sector are arranged opposite the housing surface and the recess of the second edge of the platform of another adjacent sector to form a radially open channel (128).The assembly comprises at least one sealing clip (140) received in the channel (128) and covering each recess and a mounting clearance formed between the two recesses. Figure to be published with the abstract: Figure 4.

Description

Title of the invention: TURBINE ASSEMBLY COMPRISING A CROWN PROVIDED WITH BLADE SECTORS TECHNICAL FIELD OF THE INVENTION

[0001] The present invention relates to the field of turbines such as a turbojet for aircraft.

[0002] The present invention relates more particularly to a low-pressure or high-pressure turbine assembly comprising a crown provided with blade sectors. TECHNOLOGICAL BACKGROUND OF THE INVENTION

[0003] Conventionally, as shown in [Fig.l], a portion of a high pressure HP or low pressure LP turbine T comprises: - at least one set 10 of moving blades comprising a crown 12 of axis X provided with circumferentially adjacent sectors 100 and each comprising: • an internal platform 110-1 and an external platform 110-2, and • at least one blade 130 each connecting the internal platform 110-1 with the external platform 110-2, - at least one set 20 of fixed blades comprising a crown 22 of axis X provided with circumferentially adjacent sectors 200 and each comprising: • an internal platform 210-1 and an external platform 210-2, and • at least one blade 230 each connecting the internal platform 210-1 with the external platform 210-2, - at least one turbine disc 30, and - at least one retaining ring 40 each arranged between the turbine disc 30 and the crowns 12, 22 of the set 10, 20, opposite the internal platform 110-1, 210-1 of each sector 100, 200 of the crown 12, 22.

[0004] Each turbine disk 30 ensures the positioning of the sectors 100 of the crown 12 of each set 10 of moving blades in an air stream and can form a support for the retaining ring 40. In addition, the turbine disks 30 make it possible to transmit the torque generated by the aerodynamic forces exerted on the sectors 100 of the crown 12 of each set 10 of moving blades by a flow F of air from the air stream. The retaining ring 40 ensures the axial maintenance of the sectors 100 of the crown 12 of each set 10 of moving blades. The internal and external platforms 110-1, 210-1, 110-2, 210-2 of the sectors 100, 200 of the crowns 12, 22 of the sets 10, 20 of moving blades and fixed blades ensure the sealing of the air stream.

[0005] As shown in [Fig.l], the sets 10 of moving blades and the sets 20 of fixed blades are arranged alternately with respect to each other in the axial direction. The flow F of hot air from the air stream flows substantially axially between the blades 130 of the sectors 100 of the crown 12 of each set 10 of moving blades.

[0006] [Fig. 2] represents a portion of a turbine T comprising a set 10 of moving blades. The internal platform 110-1 of each sector 100 of the crown 12 is arranged opposite the internal platform 110-1 of an adjacent sector 100 and spaced circumferentially according to a mounting clearance J1, and the external platform 110-2 of each sector 100 of the crown 12 is arranged opposite the external platform 110-2 of an adjacent sector 100 and spaced circumferentially according to the same mounting clearance JL

[0007] However, as illustrated in Figures 2 and 3, the presence of the mounting clearance J1 involves phenomena of leakage of hot air from the flow F and its reintroduction into non-flow cavities, which causes a drop in the efficiency of the turbine. In addition, the reintroduction of hot air into the non-flow cavities has an impact on the temperature of the surrounding parts as well as on their service life. This phenomenon can also occur between two sectors 110, 210 at the level of the external platform 110-2 of the set 10 of moving blades 12 as well as at the level of the external platforms 210-1 and internal platforms 210-2 of the set 20 of fixed blades 22. Summary of the invention

[0008] The invention provides a solution for solving at least one of the problems mentioned above, by proposing a turbine assembly comprising a crown of adjacent blade sectors and sealing means between the different sectors.

[0009] A first aspect of the invention relates to a turbine assembly comprising a crown of axis X comprising circumferentially adjacent blade sectors and each comprising a sealed platform comprising a first connecting edge and a second connecting edge circumferentially opposite each other, the first connecting edge of the sealed platform of a sector being opposite and spaced from the second connecting edge of the sealed platform of the adjacent sector. Each of the first and second connecting edges of the sealed platform of each sector comprises a housing surface and a step extending from the housing surface towards, respectively, the second or the first connecting edge, the housing surface and the step of the first connecting edge of the sealed platform of a sector being arranged opposite respectively the housing surface and the detachment of the second connecting edge of the sealed platform from another adjacent sector to form a radially open channel. The assembly comprises at least one sealing clip each received in the corresponding channel and covering each detachment of the first and second connecting edges, and a mounting clearance formed circumferentially between the two detachments.

[0010] The turbine assembly according to the invention makes it possible, thanks to the presence of sealing clips each arranged between two internal platforms and / or between two external platforms of two adjacent sectors, to completely cover the mounting clearance formed between the recesses of the sealed platforms of two adjacent sectors and thus to limit the phenomena of air leaks from an air stream through these mounting clearances. Each sealed platform can be an internal platform or an external platform of a sector of the crown. Consequently, this makes it possible to improve the sealing of the air stream and thus to improve the efficiency of the turbine. In addition, the presence of a channel formed by a first and a second connecting edge of the sealed platform of two adjacent sectors ensures the circumferential blocking of the retaining clip relative to the sectors.The terms "waterproof" and "sealing", as used for example in the expressions "waterproof platform" and "sealing clip", mean an improvement in sealing which may not be airtight.

[0011] Advantageously, the turbine assembly is according to which: - the watertight platform of each sector extends axially between an upstream end and a downstream end connected to each other by the two connecting edges, - each step of the first and second connecting edges of the watertight platform of each sector extends axially from the upstream end to the downstream end of the watertight platform, and - each sealing clip comprises a sealing wall extending axially between an upstream end located at the upstream end of the sealed platform and a downstream end located at the downstream end of the sealed platform and covering the entire assembly clearance; such a feature makes it possible to axially cover the entire assembly clearance with the sealing clip and thus improve the sealing of the vein.

[0012] Preferably, the sealing clip comprises an upstream rim and a downstream rim each extending respectively from the upstream or downstream end of the sealing wall and folded respectively against the upstream end or the downstream end of the sealed platform. Such a characteristic ensures the axial locking of the sealing clip in the channel of the crown.

[0013] Advantageously, the sealing wall of the sealing clip comprises first and second closing edges opposite each other circumferentially, the first closing edge bearing against the housing surface of the first connecting edge of the internal and / or external platform of a sector and the second closing edge bearing against the housing surface of the second connecting edge of the internal and / or external platform of another adjacent sector. Such a characteristic makes it possible to circumferentially fill the entire channel with the sealing clip and thus ensure the sealing of the air stream.

[0014] Preferably, the turbine assembly is according to which: - each sealed platform comprises a blade face and an off-blade face radially opposed and connected to each other by the first and second connecting edges, - each housing surface of the first and second connecting edges of the watertight platform of each sector extends substantially perpendicular to the blade face of the watertight platform, - each step of the first and second connecting edges of the sealed platform of each sector comprises a first surface substantially perpendicular to the housing surface and a second surface substantially perpendicular to the first surface and extending radially to the off-blade surface of the sealed platform.

[0015] Advantageously, the turbine assembly is according to which: - the first two surfaces of the recesses of the same channel of the crown are arranged in the same circumferential plane and spaced from each other by the mounting clearance, and - the sealing clip comprises a contact surface arranged to bear against the first two surfaces of the recesses of the first and second connecting edges of the sealed platform of each sector; such a characteristic makes it possible to form a flat channel in which the sealing clip is arranged.

[0016] According to an alternative embodiment of the sealing clip, the sealing clip comprises a first and a second support surface each extending circumferentially from the first or second closing edge of the sealing wall and each arranged to bear against the blade face of the sealed platform of two adjacent sectors of the crown; such a characteristic makes it possible to circumferentially increase the surface area of ​​the sealing wall of the sealing clip and thus to improve the sealing of the air stream.

[0017] According to a first particular embodiment of the sector of the turbine assembly, each sector of the crown comprises an internal platform and a platform external platforms connected to each other by a single blade, and in that the watertight platform corresponds to the external platform or the internal platform.

[0018] According to a second embodiment of the sector of the turbine assembly, each sector of the crown comprises an internal platform and an external platform connected to each other by several blades, and in that the sealed platform corresponds to the external platform or to the internal platform.

[0019] According to a first exemplary embodiment of the turbine assembly, each sealed platform and the sealing surface of each sealing clip comprise: - an upstream section including the upstream end, - a downstream section including the downstream end, - a central section arranged between the upstream section and the downstream section, - a first connecting section extending from the upstream section to the section central, the first section being substantially perpendicular to the upstream section, and - a second connecting section extending from the central section to the downstream section, the second connecting section being substantially perpendicular to the downstream section.

[0020] According to a second exemplary embodiment of the turbine assembly, a blade surface of each sealed platform and the sealing surface of each sealing clip is a flat surface extending from the upstream end to the downstream end.

[0021] A second aspect of the invention relates to a high or low pressure turbine comprising an assembly according to the first aspect of the invention.

[0022] 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

[0023] Other advantages and characteristics of the invention will appear on reading the following description, illustrated by the figures in which: - [Fig.l], already described, is a schematic side view of a portion of a turbine comprising sets of moving blades and sets of fixed blades according to the state of the art; - [Fig.2], already described, is a partial perspective view of a portion of a turbine comprising a set of moving blades according to the state of the art; - [Fig.3], already described, is a detailed partial front view of a set of moving blades of [Fig.2]; - [Fig.4] is a perspective view of a moving blade turbine assembly according to an example of a first embodiment; - [Fig.5] is a perspective view of a sealing clip according to [Fig.4]; - [Fig.6] is a perspective view of a sealing clip according to a variant embodiment; - [Fig.7] is a partial view of a fixed blade turbine assembly according to an example of a second embodiment. DETAILED DESCRIPTION

[0024] An exemplary embodiment of a turbine assembly according to the invention is described in detail below, with reference to the accompanying drawings. This example illustrates the characteristics and advantages of the invention.

[0025] Unless otherwise specified, the same element appearing in different figures has a single reference.

[0026] For the understanding of the invention, the radial, tangential and axial orientations will be adopted according to the reference RTA indicated in the figures, the tangent axes T and axial A of which extend in a horizontal plane according to the orientation in the figures. The axial axis A is parallel to an axis of rotation X of a crown of a turbine assembly. The upstream of the crown towards the downstream of the crown is oriented according to the axial axis A of the reference RTA. The radial orientation R extends radially relative to the axis of rotation X.

[0027] In the description, the terms "upstream" and "downstream" are defined with respect to the direction of air flow from the air inlet into the turbine to the air outlet from the turbine. In addition, the terms "internal" and "external" are also defined with respect to the axis X of rotation of the turbine wheel disc, the term "internal" designates the elements axially furthest from the axis of rotation X, as opposed to the term "external" which designates the elements axially closest to the axis X.

[0028] [Fig. 4] represents a set 10 of blades of a turbine T according to an example of a first embodiment. [Fig. 7] represents a set 20 of blades of a turbine T according to an example of a second embodiment. According to the first embodiment, each reference begins with the number 1 and according to the second embodiment, each reference begins with the number 2.

[0029] The assembly 10 according to the first embodiment and the assembly 20 according to the second embodiment each comprise a ring 12, 22 of axis X comprising sectors 100, 200 circumferentially adjacent to each other. Each sector 100, 200 comprises an internal platform 110-1, 210-1 and an external platform 110-2, 210-2 (the external platform 110-2 of the assembly 10 being similar to that of FIGS. 1 and 2).

[0030] According to an example of the first embodiment as shown in [Fig.4], each sector 100 of the crown 12 of the assembly 10 comprises a single blade 130 connecting the internal platform 110-1 to the external platform 110-2. According to another example, not shown, of the first embodiment, each sector 100 comprises several blades 130 connecting the internal platform 110-1 to the external platform 110-2.

[0031] According to an example of the second embodiment, as shown in [Fig.7], each sector 200 of the crown 22 of the assembly 20 comprises several blades 230 each connecting the internal platform 210-1 to the external platform 210-2. According to another example not shown of the second embodiment, each sector 200 comprises a single blade 230 connecting the internal platform 230-1 to the external platform 230-2.

[0032] The assembly 10 according to the first embodiment is a set 10 of moving blades and the assembly 20 according to the second embodiment is a set 20 of fixed blades. According to an example of the first embodiment, as shown in [Fig. 4], only the internal platform 110-1 of each sector 100 is a sealed platform. According to an example of the second embodiment, as shown in [Fig. 7], only the external platform 220-1 of each sector 200 is a sealed platform. According to another example of the first and second embodiments, not shown, the internal platform 110-1, 210-1 and the external platform 110-2, 210-2 each correspond to a sealed platform.

[0033] According to the first and second embodiments, the assembly 10, 20 comprises at least one sealing clip 140, 240 each arranged between two adjacent sealed platforms, respectively in the examples as shown in FIGS. 4 and 7, between two internal platforms 110-1 of the assembly 10 and between two external platforms 220-1 of the assembly 20.

[0034] The turbine T may comprise: - at least one set 10 of moving blades according to one of the examples of the first embodiment and / or at least one set 20 of fixed blades according to the second embodiment, and - at least one turbine disc 30 (for example similar to that visible in [Fig.2]).

[0035] In the case where the turbine T comprises at least one set 10 of moving blades, it may further comprise at least one retaining ring 40 (for example similar to that visible in [Fig.2]) each arranged between the turbine disk 30 and the crown 12 of the set 10 of fixed blades, opposite the internal platform 110-1 of each sector 100.

[0036] The example of the first embodiment, as shown in [Fig.4], is described in more detail below. Each internal platform 110-1, corresponding to a sealed platform, comprises: - an upstream end 110A and a downstream end 110B axially opposite the upstream end 110A, - a first connecting edge 112 and a second connecting edge 114 circumferentially opposite the first connecting edge 112, the first connecting edge 112 of the internal platform 110-1 of a sector 100 being opposite and spaced from the second connecting edge 114 of the internal platform 110-1 of the adjacent sector 100, - a blade face 120 on which the blade 130 is fixed, and an off-blade face 121 radially opposite the blade face 120.

[0037] The first connecting edge 112 of the internal platform 110-1 of each sector 100 of a ring 12 comprises a housing surface 116 and a step 118 extending from the housing surface 116 towards the second connecting edge 114. The second connecting edge 112 of the internal platform 110-1 of each sector 100 of a ring 12 comprises a housing surface 116 and a step 118 extending from the housing surface 116 towards the first connecting edge 112. The step 118 of the first connecting edge 112 of the internal platform 110-1 of a sector 100 and the step 118 of the second connecting edge 114 of the internal platform 110-1 of another adjacent sector 100 are arranged opposite each other and spaced circumferentially from each other by a JL mounting clearance

[0038] The housing surface 116 and the recess 118 of the first connecting edge 112 of the internal platform 110-1 of a sector 100 being arranged facing respectively the housing surface 116 and the recess 118 of the second connecting edge 114 of the internal platform 110-1 of another adjacent sector 100 to form a channel 128 open radially towards the blade face 120 of the internal platform 110-1.

[0039] More particularly, each step 118 of the first and second connecting edges 112, 114 of the internal platform 110-1 of each sector 100 extends axially from the upstream end 110A to the downstream end 110B of the internal platform 110-1 and comprises: - a first surface 118-1 substantially perpendicular to the housing surface 116, the two first surfaces 118-1 of the recesses 118 of two adjacent sectors 110 being arranged in the same plane and circumferentially separated from each other by the mounting clearance Jl, and - a second surface 118-2 substantially perpendicular to the first surface 118-1 and extending radially to the off-blade surface 121 of the internal platform 110-1, the two second surfaces 118-2 of the recesses 118 of two adjacent sectors 110 being arranged parallel and circumferentially separated from each other by the mounting clearance Jl.

[0040] Consequently, each channel 128 is formed by two housing surfaces 116 and by two first surfaces 118-1 of the recesses 118 of two adjacent sectors 110.

[0041] More particularly, as illustrated in figures 5 and 6, each internal platform 110-1 of the crown 12 of the set 10 of mobile blades according to a first embodiment of the internal platform 110-1 is delimited into five sections: - an upstream section 122 comprising the upstream end 110A, - a downstream section 126 comprising the downstream end 110B, - a central section 124 arranged between the upstream section 122 and the downstream section, - a first connecting section 123 extending from the upstream section 122 to central section 124, the first section being substantially perpendicular to the upstream section 122, and - a second connecting section 125 extending from the central section 124 to the downstream section 126, the second connecting section 125 being substantially perpendicular to the downstream section 126.

[0042] The upstream and downstream sections 122, 126 extend axially in a direction opposite to the blade 130 and are substantially parallel to each other. In addition, the upstream section 122 is radially closer to the axis X than the downstream section 126.

[0043] Each sealing clip 140 is received in one of the channels 128 and covers each recess 118 of the first and second connecting edges 112, 114 of the internal platform 110-1 of each sector 100, and the mounting clearance J1 formed by the two recesses 118 of two adjacent sectors 100.

[0044] As shown in Figures 5 and 6, each sealing clip 140 comprises a sealing wall 142 comprising: - an upstream end 142A and a downstream end 142B axially opposite the upstream end 142A, - a first closing edge 144 and a second closing edge 145 circumferentially opposite the first closing edge 144, and - a blade face 150A and a contact face 150B radially opposite the blade face 150A, - an upstream rim 146A extending from the upstream end 142A of the sealing wall 142, and - a downstream rim 146B extending from the downstream end 142B of the sealing wall 142.

[0045] More particularly, the sealing clip 140 has a shape complementary to that of the channel 128 and comprises five sections: - an upstream section 152 comprising the upstream end 140A, - a downstream section 156 comprising the downstream end 140B, - a central section 154 arranged between the upstream section 152 and the downstream section 156, - a first connecting section 123 extending from the upstream section 122 to the central section 124, the first section being substantially perpendicular to the upstream section 122, and - a second connecting section 125 extending from the central section 124 to the downstream section 126, the second connecting section 125 being substantially perpendicular to the downstream section 126.

[0046] According to a variant of the sealing clip 140, as shown in [Fig.6], the sealing clip 140 further comprises: - a first support surface 148 extending circumferentially from the first closing edge 144 of the sealing wall 142, and - a second support surface 149 extending circumferentially from the second closing edge 145 of the sealing wall 142.

[0047] Advantageously, the sealing clip 140 is made in a single piece.

[0048] As shown in [Fig.4], in the mounted position of the sealing clip 140 in a channel 128 of crown 12 of a set 10 of moving blades: - the first closing edge 144 being arranged opposite the first connecting edge 112 of the internal platform 110-1 of a sector 100, - the second closing edge 145 being arranged opposite the second connecting edge 114 of the internal platform 110-1 of the adjacent sector 100, - the blade face 150A of the sealing wall 142 of the sealing clip 140 is arranged at the level of the blade face 120 of the internal platform 110-1, - the contact face 150B of the sealing wall 142 of the sealing clip 140 is arranged to bear against the first surface 118-1 of the recess 118 of the first connecting edge 112 and against the first surface 118-1 of the recess 118 of the second connecting edge 114 of the internal platform 110-1, - the upstream edge 146A of the sealing wall 142 of the sealing clip 140 is folded against the upstream end 112 of the internal platform 110-1, and - the downstream edge 146B of the sealing wall 142 of the sealing clip 140 is folded against the downstream end 114 of the internal platform 110-1.

[0049] More particularly, in the mounted position of the sealing clip 140 according to the variant embodiment of [Fig.6] in a channel 128 of the crown 12 of a set 10 of mobile blades: - the first support surface 148 of the sealing wall 142 is arranged to bear against the blade face 120 of the internal platform 110-1, on the side of the first connecting edge 112 of the internal platform 110-1 of one of the sectors 100 of the crown 12, and - the second support surface 149 of the sealing wall 142 is arranged to bear against the blade face 120 of the platform 110, on the side of the second connecting edge 114 of the internal platform 110-1 of one of the sectors 100 of the crown 12.

[0050] According to an exemplary embodiment not shown, the sealing clip 140 is arranged between two adjacent external platforms 110-2. In this case, each external platform 110-2 also comprises upstream and downstream ends 110A, 110B, a first and a second connecting edges 112, 114, and a blade face 120 and an off-blade face 121. The first and second connecting edges 112, 114 of the external platform 110-2 are identical to those of the internal platform 110-1. However, the geometric shape of the external platform 110-2 may be different from that of the internal platform 110-1 with regard to its axial length and its delimitation into different sections.

[0051] The example of the second embodiment, as shown in [Fig.7], is described in more detail below. Each external platform 210-2, corresponding to a sealed platform, comprises: - an upstream end 210A and a downstream end 210B axially opposite the upstream end 210A, - a first connecting edge 212 and a second connecting edge 214 circumferentially opposite the first connecting edge 212, the first connecting edge 212 of the external platform 210-2 of a sector 200 being opposite and spaced from the second connecting edge 214 of the external platform 210-2 of the adjacent sector 200, - a blade face 220 on which the blade 230 is fixed, and an off-blade face 221 radially opposite the blade face 220.

[0052] The first connecting edge 212 of the external platform 210-2 of each sector 200 of a ring 22 comprises a housing surface 216 and a step 218 extending from the housing surface 216 towards the second connecting edge 214. The second connecting edge 212 of the external platform 210-2 of each sector 200 of a ring 22 comprises a housing surface 216 and a step 218 extending from the housing surface 216 towards the first connecting edge 212. The recess 218 of the first connecting edge 212 of the external platform 210-2 of a sector 200 and the recess 218 of the second connecting edge 214 of the external platform 210-2 of another adjacent sector 200 are arranged opposite each other and spaced circumferentially from each other by a mounting clearance J2.

[0053] The housing surface 216 and the recess 218 of the first connecting edge 212 of the external platform 210-2 of a sector 200 being arranged facing respectively the housing surface 216 and the recess 218 of the second connecting edge 214 of the external platform 210-2 of another adjacent sector 200 to form a channel 228 open radially towards the blade face 220 of the external platform 210-2.

[0054] More particularly, each step 118 of the first and second connecting edges 112, 114 of the external platform 210-2 of each sector 200 extends axially from the upstream end 210A to the downstream end 210B of the external platform 210-2 and comprises: - a first surface 218-1 substantially perpendicular to the housing surface 216, the two first surfaces 218-1 of the recesses 218 of two adjacent sectors 210 being arranged in the same plane and circumferentially separated from each other by the mounting clearance J2, and - a second surface 218-2 substantially perpendicular to the first surface 218-1 and extending radially to the off-blade surface 221 of the external platform 210-2, the two second surfaces 218-2 of the recesses 218 of two adjacent sectors 210 being arranged parallel and circumferentially separated from each other by the mounting clearance J2.

[0055] Consequently, each channel 228 is formed by two housing surfaces 216 and by two first surfaces 218-1 of the recesses 218 of two adjacent sectors 210.

[0056] More particularly, the blade face 220 of each external platform 210-2 of the crown 22 of the set 20 of fixed blades according to a first embodiment of the external platform 210-2 is a flat surface extending from the upstream end 210A towards the downstream end 210B of the external platform 210-2.

[0057] Each sealing clip 240 is received in one of the channels 228 and covers each recess 218 of the first and second connecting edges 212, 214 of the external platform 210-2 of each sector 200, and the mounting clearance J2 formed by the two recesses 218 of two adjacent sectors 200.

[0058] Each sealing clip 240 comprises a sealing wall 242 comprising: - an upstream end 242A and a downstream end 242B axially opposite the upstream end 242A, - a first closing edge 244 and a second closing edge 245 circumferentially opposite the first closing edge 244, and - a blade face 250A and a contact face 250B radially opposite the blade face 250A, - an upstream rim 246A extending from the upstream end 242A of the sealing wall 242, and - a downstream rim 246B extending from the downstream end 242B of the sealing wall 242.

[0059] More particularly, the sealing clip 240 has a shape complementary to that of the channel 228 according to which its sealing surface 242 is a flat surface extending from the upstream end 240A towards the downstream end 240B of the sealing clip 240.

[0060] According to a variant of the sealing clip 240, not shown, the sealing clip 240 further comprises: - a first support surface extending circumferentially from the first closing edge 244 of the sealing wall 122, and - a second support surface extending circumferentially from the second closing edge 245 of the sealing wall 242.

[0061] Advantageously, the sealing clip 140 is made in a single piece.

[0062] As shown in [Fig.7], in the mounted position of the sealing clip 240 in a channel 228 of the crown 22 of a set 20 of fixed blades: - the first closing edge 244 being arranged opposite the first connecting edge 212 of the external platform 210-2 of a sector 200, - the second closing edge 245 being arranged opposite the second connecting edge 214 of the external platform 210-2 of the adjacent sector 200, - the blade face 250A of the sealing wall 242 of the sealing clip 240 is arranged at the level of the blade face 220 of the external platform 210-2, - the contact face 250B of the sealing wall 242 of the sealing clip 240 is arranged to bear against the first surface 218-1 of the recess 218 of the first connecting edge 212 and against the first surface 218-1 of the recess 218 of the second connecting edge 214 of the external platform 210-2, - the upstream edge 246A of the sealing wall 242 of the sealing clip 240 is folded against the upstream end 212 of the external platform 210-2, and - the downstream edge 246B of the sealing wall 242 of the sealing clip 240 is folded against the downstream end 214 of the external platform 210-2.

[0063] According to an exemplary embodiment not shown, the sealing clip 140 is arranged between two adjacent internal platforms 210-1. In this case, each platform The internal platform 210-1 also includes upstream and downstream ends 210A, 210B, first and second connecting edges 212, 214, and a blade face 220 and an off-blade face 221. The first and second connecting edges 212, 214 of the internal platform 210-1 are identical to those of the external platform 210-2. However, the geometric shape of the internal platform 210-1 may be different from that of the external platform 10-2 with respect to its axial length.

[0064] A high pressure or low pressure turbine T comprising a set 10 of moving blades and / or a set 20 of fixed blades according to the invention, makes it possible, thanks to the presence of sealing clips 140, 240 each arranged in a channel 128, 228 between two internal platforms 110-1, 210-1 or external platforms 210-1, 210-2, to close the mounting clearance J1, J2 formed between two recesses 118, 218 and thus to optimize the sealing of the air stream of the turbine and thus to increase the service life of the various parts of the turbine T.

Claims

1.

2. Claims Turbine assembly (10) comprising a crown of blades (12, 22) of axis X comprising circumferentially adjacent blade sectors (100, 200) and each comprising at least one sealed platform (110-1, 210-1, 110-2, 212-2) comprising a first connecting edge (112, 212) and a second connecting edge (114, 214) circumferentially opposite one another, the first connecting edge (112, 212) of the sealed platform (110-1, 110-2, 210-1, 210-2) of a sector (100, 200) being opposite and spaced from the second connecting edge (114, 214) of the sealed platform (110-1, 110-2, 210-1, 210-2) of the adjacent sector (100, 200), characterized in that: - each of the first and second connecting edges (112, 212, 114, 214) of the sealed platform (110-1, 110-2, 210-1, 210-2) of each sector (100, 200) comprises a housing surface (116, 216) and a step (118, 218) extending from the housing surface (116, 216) towards, respectively, the second or the first connecting edge (112, 114, 212, 214), the housing surface (116, 216) and the step (118, 218) of the first connecting edge (112, 212) of the sealed platform (110-1, 110-2, 210-1, 210-2) of a sector (100, 200) being arranged facing respectively the housing surface (116, 216) and the recess (118, 218) of the second connecting edge (114, 214) of the sealed platform (110-1, 110-2, 210-1, 210-2) of another adjacent sector (100, 200) to form a radially open channel (128, 228), and - the assembly (1) comprises at least one sealing clip (140) each received in the corresponding channel (128, 228) and covering each recess (118, 218) of the first and second connecting edges (112, 114, 212, 214), and a mounting clearance (Jl, J2) formed circumferentially between the two recesses (118, 218). Turbine assembly (10, 20) according to claim 1, characterized in that: - the sealed platform (110-1, 110-2, 210-1, 210-2) of each sector (100, 200) extends axially between an upstream end (110A, 210A) and a downstream end (110B, 210B) connected to each other by the two connecting edges (112, 114, 212, 214), - each step (118, 218) of the first and second connecting edges (112, 114, 212, 214) of the sealed platform (110-1, 110-2, 210-1, 210-2) of each sector (100, 200) extends axially from the upstream end (110A, 210A) to the downstream end (110B, 210B) of the sealed platform (110-1, 110-2, 210-1, 210-2), and - each sealing clip (140, 240) comprises a sealing wall (142, 242) extending axially between an upstream end (142A, 242A) located at the upstream end (110A, 210A) of the sealed platform (110-1, 110-2, 210-1, 210-2) and a downstream end (142B, 242B) located at the downstream end (110B, 210B) of the sealed platform (110-1, 110-2, 210-1,210-2) and covering the entire assembly set (Jl, J2).,

3. Turbine assembly (10, 20) according to claim 2, characterized in that the sealing clip (140, 240) comprises an upstream rim (146A, 246A) and a downstream rim (146B, 246B) each extending respectively from the upstream end (142A, 242A) or downstream end (142B, 242B) of the sealing wall (142, 242) and folded respectively against the upstream end (112, 212) or the downstream end (114, 214) of the sealed platform (110-1, 110-2, 210-1, 210-2).

4. Turbine assembly (10, 20) according to any one of the preceding claims, characterized in that the sealing wall (142, 242) of the sealing clip (140, 240) comprises a first closing edge (144, 244) and a second closing edge (145, 245) opposite each other circumferentially, the first closing edge (144, 244) bearing against the housing surface (116, 216) of the first connecting edge (112, 212) of the sealed platform (110-1, 110-2, 210-1, 210-2) of a sector (100, 200) and the second closing edge (145, 245) bearing against the housing surface (116, 216) of the second edge connecting (114, 214) of the watertight platform (110-1, 110-2, 210-1, 210-2) of another adjacent sector (100, 200).

5. Turbine assembly (10, 20) according to any one of the preceding claims, characterized in that: - each sealed platform (110-1, 110-2, 210-1, 210-2) comprises a blade face (120, 220) and an off-blade surface (121, 221) radially opposite and connected to each other by the first and second connecting edges (112, 114, 212, 214), - each housing surface (116, 216) forming a channel (128, 228) of the blade ring (12, 22) extends substantially perpendicular to the blade face (120, 220) of the platform (110-1, 110-2, 210-1, 210-2), - each step (118, 218) forming a channel (128, 238) comprises a first surface (118-1) substantially perpendicular to the housing surface (116, 216) and a second surface (118-2) substantially perpendicular to the first surface (118-1) and extending radially to the off-blade surface (121, 212) of the sealed platform (110-1, 110-2, 210-1, 210-2).

6. Turbine assembly (10, 20) according to claim 5, characterized in that: - the two first surfaces (118-1) of the recesses (118, 218) of the same channel (128) of the blade ring (12, 22) are arranged in the same circumferential plane and spaced apart from each other by the mounting clearance (J1, J2), and - the sealing clip (130, 230) comprises a contact surface (150B, 250B) arranged to bear against the two first surfaces (118-1) of the recesses (118, 218) of the same channel (128, 228) of the blade ring (12, 22).

7. A turbine assembly (10, 20) according to any preceding claim, characterized in that the sealing clip (140, 240) comprises first and second support surfaces (148, 149) each extending circumferentially from the first or second closing edge (144, 145, 244, 245) of the wall sealing (142, 242) and each arranged to bear against the blade face (120, 220) of the sealed platform (110-1, 110-2, 210-1, 210-2) of two adjacent sectors (100, 200) of the blade crown (12, 22).

8. Turbine assembly (10) according to any one of the preceding claims, characterized in that each sector (100) of the crown of mobile blades (12) comprises an internal platform (110-1) and an external platform (210-1) connected to each other by a single blade (130), and in that each sealed platform corresponds to the internal platform (110-1) or to the external platform (110-2).

9. Turbine assembly (10) according to any one of claims 1 to 7, characterized in that each sector (200) of the crown of fixed blades (22) comprises an internal platform (210-1) and an external platform (210-2) connected to each other by several blades (230), and in that each sealed platform corresponds to the internal platform (110-1) or to the external platform (110-2).

10. Turbine characterized in that it comprises at least one assembly (10) according to any one of claims 1 to 9.

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