ROTOR BLADE ASSEMBLY COMPRISING A LOCKING ELEMENT FOR AXIALLY SECURING A REINFORCEMENT ELEMENT OF A REINFORCEMENT STRUCTURE PROVIDED RADIALLY INWARDLY

Abstract

A rotor blade assembly group for an engine includes a blade carrier with rotor blades along a circle line about a central axis of the group, wherein the blade carrier has a carrier section extending radially inwards toward a central axis, the carrier section includes a connecting area at which a stiffening structure with a stiffening element is fixedly attached, and the stiffening element is arranged at a face side of the blade carrier. The stiffening element is axially secured at the face side of the blade carrier via a barrier element, that (a) is affixed radially further inside at or to a flange section of the blade carrier, or (b) is formed in front of the blade carrier and engages around the stiffening element with at least one barrier element section.

Claims

1. A rotor blade assembly group for an engine, with at least one blade carrier which has at least one rotor blade that is provided with multiple rotor blades along a circle line about a central axis of the rotor blade assembly group, wherein the blade carrier has a carrier section that extends radially inwards in the direction of the central axis with respect to the at least one rotor blade, the carrier section comprises a connecting area at which a stiffening structure with at least one stiffening element is fixedly arranged, and the at least one stiffening element is arranged at a face side of the blade carrier, wherein the at least one stiffening element is axially secured at the face side of the blade carrier via at least one barrier element that is (a) fixated radially further inside at or to a flange section of the blade carrier, or (b) is formed by the blade carrier and with at least one barrier element section engaging around the stiffening element.

2. The rotor blade assembly group according to claim 1, wherein the barrier element that is affixed at or to the flange section of the blade carrier extends radially outwards with a base.

3. The rotor blade assembly group according to claim 2, wherein an axially extending barrier element section for axial securing of the at least one stiffening element is provided at the base.

4. The rotor blade assembly group according claim 1, wherein the blade carrier is connected to one further blade carrier via the flange section.

5. The rotor blade assembly group according to claim 4, wherein at one carrier section of the further blade carrier a further stiffening structure with at least one further stiffening element is fixedly attached, the two stiffening elements of the interconnected blade carriers are located opposite each other, and the barrier element is arranged between the two stiffening elements.

6. The rotor blade assembly group according to claim 5, wherein the barrier element has two barrier element sections of which a first barrier element section extends axially in the direction of the one stiffening element and a second barrier element section extends axially opposite to the same in the direction of the other stiffening element.

7. The rotor blade assembly group according to claim 5, wherein the stiffening structures of the two interconnected blade carriers are axially secured against each other via the barrier elements.

8. The rotor blade assembly group according to claim 1, wherein the barrier element section of the barrier element formed by the blade carrier with which the barrier element engages around the stiffening element extends radially inwards.

9. The rotor blade assembly group according to claim 1, wherein the barrier element formed by the blade carrier comprises at least two barrier element sections that succeed each other along a circumferential direction about the central axis, and between which a radially and axially extending gap is present.

10. The rotor blade assembly group according to claim 9, wherein at the stiffening element at least one radially protruding securing section is provided, that can be inserted into the gap between the two barrier element sections in the axial direction for mounting the rotor blade assembly group.

11. The rotor blade assembly group according to claim 10, wherein, in the assembled state of the rotor blade assembly group according to the intended use, one of the at least two barrier element sections that succeed one another along a circumferential direction about the central axis engage around at least one radially protruding securing section.

12. The rotor blade assembly group according to claim 9, wherein multiple gaps are present at the barrier element, wherein one gap is respectively provided between two barrier element sections that succeed one another along the circumferential direction, and/or multiple securing sections arranged at a distance to each other are provided at the stiffening element in the circumferential direction.

13. The rotor blade assembly group according to claim 1, wherein at least one separately mountable locking element for securing the stiffening element is provided against twisting relative to the blade carrier.

14. The rotor blade assembly group according to claim 13, wherein the at least one locking element is formed in a pin-shaped manner and/or is axially mountable at the blade carrier.

15. The rotor blade assembly group according to claim 14, wherein the at least one locking element can be affixed via a securing element at the blade carrier.

16. The rotor blade assembly group according to claim 9, wherein the at least one locking element is inserted into the gap between the two barrier element sections.

17. The rotor blade assembly group according to claim 12, wherein a recess is provided between two of the securing sections provided at the stiffening element, which in the assembled state of the rotor blade assembly group according to the intended use is located at least partially in the gap between the two barrier element sections, so that the locking element inserted in the gap also meshes in the recess of the stiffening element.

18. The rotor blade assembly group according to claim 17, wherein the recess of the stiffening element has a smaller extension in the circumferential direction than the gap of the barrier element.

19. The rotor blade assembly group according to claim 1, wherein at least one cooling hole for the cooling air that is to be guided to the stiffening structure is provided at the carrier section.

20. The rotor blade assembly group according to claim 1, wherein at least one stiffening element is formed in a ring-shaped manner.

21. The rotor blade assembly group according to claim 1, wherein at least one stiffening element has a metal matrix composite.

22. The rotor blade assembly group according to claim 21, wherein at least one stiffening element has an externally sheathed core of a metal matrix composite.

23. A gas turbine engine with at least one rotor blade assembly group according to claim 1.

24. A method for mounting a stiffening element at a rotor blade assembly group provided for an engine, wherein the rotor blade assembly group comprises at least one blade carrier that has at least one rotor blade that is provided with multiple rotor blades along a circle line about a central axis of the rotor blade assembly group, wherein the blade carrier has a carrier section which extends radially inwards in the direction of the central axis with respect to the at least one rotor blade, and at which a stiffening structure with the stiffening element is mounted at a face side of the blade carrier and the stiffening element is fixedly attached, wherein the stiffening element is axially secured at the face side of the blade carrier via at least one barrier element that (a) is fixated radially further inside at or to a flange section of the blade carrier, or (b) is formed in front of the blade carrier and engages around the stiffening element with at least one barrier element section.

25. The method according to claim 24, wherein the blade carrier is connected in a torque-proof manner to a further engine component via the flange section, with the barrier element being axially pressed against the stiffening element.

26. The method according to claim 24, wherein the stiffening element is initially arranged in a mounting position at the carrier section, and is subsequently rotated into a barrier position along a circumferential direction about the central axis relative to the carrier section, in which the at least one securing section radially protruding at the stiffening element is received inside a gap bordered by the at least one barrier element section, so that the barrier element section engages around the stiffening element at the securing section.

27. The method according to claim 26, wherein, if the stiffening element is in the barrier position, a locking element is mounted at the blade carrier, via which the stiffening element is secured against a twisting relative to the carrier section.

Description

[0055] Herein:

[0056] FIG. 1 shows, in a sectioned side view and in sections, a first embodiment variant of a proposed rotor blade assembly group that is installed in a high-pressure turbine of an engine;

[0057] FIG. 2 shows a second embodiment variant in a view corresponding to FIG. 1;

[0058] FIG. 3 shows a third embodiment variant in a view corresponding to FIG. 1;

[0059] FIG. 4 shows, in a perspective front view and in sections and on an enlarged scale, the axial securing of a stiffening element of the rotor blade assembly group of FIG. 3 via multiple barrier element sections of a blade-carrier-side barrier element engaging around it, with the barrier position of the stiffening element at a blade carrier being secured by means of an inserted pin-shaped locking element and with a securing bracket being fixedly attached thereat;

[0060] FIG. 5 shows, on an enlarged scale, a further perspective front view with the stiffening element in the barrier position and the locking element that is to be inserted thereat;

[0061] FIG. 6 shows, in sections, a detailed rendering of the stiffening element in its barrier position with inserted pin-shaped locking element and a securing bracket securing the locking element;

[0062] FIG. 6A shows a sectional view according to the section line A-A of FIG. 6;

[0063] FIG. 7 shows a cross-sectional view of a turbofan engine in which an embodiment variant of a rotor blade assembly group according to the invention is used in the area of a high-pressure turbine.

[0064] FIG. 8 shows, in sections and in sectioned rendering, a design of rotor blade rows of a turbine of a gas turbine engine as it is known from the state of the art

[0065] FIG. 7 illustrates schematically and in sectional view, a gas turbine engine T, in which the individual engine components are arranged in succession along a rotational axis or central axis M and the engine T is embodied as a turbofan engine. By means of a fan F, air is suctioned in along an entry direction at an inlet or an intake E of the engine T. This fan F, which is arranged inside a fan housing FC, is driven by means of a rotor shaft S that is set into rotation by a turbine TT of the engine T. Here, the turbine TT connects to a compressor V, which for example has a low-pressure compressor 11 and a high-pressure compressor 12, and where necessary also a medium-pressure compressor. The fan F supplies air to the compressor V, on the one hand, and, on the other, to a secondary flow channel or bypass channel B for creating a thrust. Here, the bypass channel B extends about a core engine that comprises the compressor V and the turbine TT, and also comprises a primary flow channel for the air that is supplied to the core engine by the fan F.

[0066] The air that is conveyed by means of the compressor V into the primary flow channel is transported into the combustion chamber section BK of the core engine where the driving power for driving the turbine TT is generated. For this purpose, the turbine TT has a high-pressure turbine 13, a medium-pressure turbine 14, and a low-pressure turbine 15. The turbine TT drives the rotor shaft S and thus the fan F by means of the energy that is released during combustion in order to generate the necessary thrust by means of the air that is conveyed into the bypass channel B. The air from the bypass channel B as well as the exhaust gases from the primary flow channel of the core engine are discharged by means of an outlet A at the end of the engine T. Here, the outlet A usually has a thrust nozzle with a centrally arranged outlet cone C.

[0067] It is known to use rotor blade assembly groups, which rotate about the central axis M and have respectively one rotor blade row and in which the rotor blades are provided at a ring-shaped or disc-shaped blade carrier, in the area of the (axial) compressor with its low-pressure compressor 11 and its high-pressure compressor 12, as well as in the area of the turbine TT. Here, the ring-shaped or disc-shaped blade carrier can in principle be integrally provided with blades, and thus be produced in bling or blisk design. Alternatively, the fixation of individual rotor blades is possible at the ring-shaped or disc-shaped blade carrier via the respective blade root. For this purpose, for example a blade root is axially inserted into a fastening groove of the blade carrier and axially secured at the respective blade carrier.

[0068] Based on FIG. 8, multiple rotor blade assembly groups 2a, 2b and 2c of the turbine TT, which are arranged behind each other along the central axis M, are illustrated by way of example. Here, the section shown in FIG. 5 only shows a part above the central axis M in the area of the medium-pressure turbine 14 or the low-pressure turbine 15. The individual rotor blade assembly groups 2a, 2b and 2c are connected to each other by means of flange connections 4.1 and 4.2 in a torque-proof manner. Further, each rotor blade assembly group 2a, 2b and 2c has respectively one ring-shaped or disc-shaped blade carrier 23, 24 or 25, at which individual rotor blades 20, 21 or 22 of a blade/vane row are arranged behind each other along a circle line about the central axis M, and are fixated at respective blade carriers 23, 24 or 25 via a blade root 200, 210 or 220 of a rotor blade 20, 21 or 22. Here, rotor blade rows of the rotor blade assembly groups 2a, 2b and 2c alternate with stationary guide vane rows in the axial direction along the central axis M. The guide vane rows respectively have guide vanes 30 or 31 that are also arranged circumferentially along a circle line about the central axis M.

[0069] Due to the high rotational speeds and the resulting loads, each blade carrier 23, 24 or 25 of a rotor blade assembly group 2a, 2b or 2c of the state of the art has a radially inwardly extending carrier section 230, 240 or 250. A disc-shaped carrier section 250 of the rear rotor blade assembly group 2c may for example serve for rotatably mounting the rotor blade assembly groups 2a, 2b and 2c that are interconnected in a torque-proof manner. In the carrier section 230, 240 of two frontal rotor blade assembly groups 2a and 2bwith regard to the flow direction through the engine Ta central passage opening O1 or O2 is provided primarily for the purpose of weight reduction, for example in the form of a bore. As for the necessary installation space of the rotor blade assembly groups 2a and 2b as well as their weight, it is above all important what radial extension the blade carriers 23 and 24 have to be able to withstand the loads that occur during operation.

[0070] In the different variants of a proposed solution, which are for example illustrated in FIG. 1 by way of example based on two rotor blade assembly groups 2a and 2b of the high-pressure turbine 13, a considerable reduction of the radially extending carrier sections 230 or 240 is achieved by providing respectively one stiffening structure 5a or 5b. Each stiffening structure 5a or 5b has two ring-shaped stiffening elements in the form of (MMC) stiffening rings 5.1 and 5.2 that are arranged to be located opposite each other at the face sides of the respective blade carriers 23 or 24. The stiffening rings 5.1 and 5.2 respectively engage in a form-fit manner around projections of a connecting area 231 or 241 of the respective carrier section 230 or 240 that forms a continuous profile in the circumferential direction. Here, the connecting area 231, 241 is respectively provided with a fir-tree-shaped (cross-sectional) profile.

[0071] Each stiffening ring 5.1, 5.2 of the respective stiffening structure 5a or 5b has a sheathed MMC core 500, for example a TiMMC core. By manufacturing the stiffening rings 5.1 and 5.2 in MMC design, a considerably higher stiffness of the blade carrier 23 or 24 is achieved with a comparatively light weight. Here, through the stiffening structure 5a or 5b with the stiffening rings 5.1 and 5.2 that are arranged at face sides of the blade carrier 23 or 24 that are facing away from ach other, in particular radially acting forces can be received. But at the same time a simpler mounting and a simple radial securing of the stiffening rings 5.1 and 5.2 that are to be mounted at the blade carrier 23 or 24 is provided through the circumferential profiling of the connecting area 231 or 241.

[0072] In the embodiment variant of FIG. 1, the one rotor blade assembly group 2a is connected in a torque-proof manner via a flange area 2300 of its carrier section 230 to two engine components by means of flange connections 7.1 and 7.2; upstream via a flange section 230a of the flange area 2300 to a first engine component, on the one hand, and at an axial distance thereto downstream via a second flange section 230b of the flange area 2300 to a second engine component in the form of the further rotor blade assembly group 2b which defines a downstream further rotor blade row of the high-pressure turbine 13. Here, the flange area 2300 extends radially further inside with respect to the connecting area 231 at the fir-tree-shaped cross-sectional profile of which the stiffening rings 5.1 and 5.2 the stiffening structure 5a of the rotor blade assembly group 2a are arranged at the font end.

[0073] For axially securing the stiffening rings 5.1 and 5.2 at the blade carrier 23, two barrier elements 6.1 and 6.2 are provided. Here, both barrier elements 6.1 and 6.2 are fixated at or to one of the flange sections 230a, 230b of the blade carrier 23. At that, an axially frontal barrier element 6.1 is fixated via the flange connection 7.1 to the flange section 230a. The barrier element 6.1 is formed at a flange section 206a at which the flange section 230a of the blade carrier 23 is fixated for forming the flange connection 7.1 The axially rear barrier element 6.2 is fixated via a [flange connection] 7.2 at or to the flange section 230b of the blade carrier 23. For forming this flange connection 7.2, the flange section 230b of the blade carrier 23 of the (first, left-hand) rotor blade assembly group 2a and a flange section 240a of the blade carrier 24 of the in flow direction downstream rotor blade row or the following (second, right-hand) rotor blade assembly group 2b are connected to each other in a torque-proof manner.

[0074] At that, the rear barrier element 6.2 is fixated at or to the flange section 230b via a base 62c, and extends radially outwards from the flange connection 7.2. Here, the base 62c can also be formed by a web, a circular disc segment or a circular disc. Formed at a radially outer end of the base 62c is a barrier element section 62a that extends axially in the direction of the (rear) stiffening ring 5.2. Through the connection of the two rotor blade assembly groups 2a and 2b to the flange sections 230b and 240a, the barrier element section 62a is pressed in the axial direction against the rear stiffening ring 5.2, and thus the stiffening ring 5.2 is axially secured at the rear face side of the blade carrier 23.

[0075] By contrast, the stiffening ring 5.1 provided at the opposite radial frontal face side abuts the barrier element section 62b of the barrier element 6.1 and is axially secured in this manner. At that, this frontal barrier element 6.1 is pressed against the stiffening ring 5.1 during the mounting of the rotor blade assembly group 2a to the flange 206a. Both stiffening rings 5.1 and 5.2 of the stiffening structure 5a are thus automatically axially secured through the barrier elements 6.1 and 6.2 as the rotor blade assembly group 2a is mounted in the high-pressure turbine 13 according to the intended use, without any need for axial securing of the stiffening rings 5.1 and 5.2, which would have to be mounted separately. Thanks to the axially acting barrier elements 6.1 and 6.2, also an axial play compensation is achieved, and the stiffening rings 5.1 and 5.2 are loaded against the blade carrier 23 with a sufficient axially acting pressing force.

[0076] For cooling the stiffening structure 5a and in particular the stiffening rings 5.1 and 5.2, cooling holes 232.1 and 232.2 are formed at the flange area 2300and thus radially further inside with respect to the connecting area 231. Here, a first row of cooling holes 232.1 succeeding each other in the circumferential direction is provided for the frontal stiffening ring 5.1. Provided at an axial distance to the same is a second row of cooling holes 232.2 for the rear stiffening ring 5.2 that also succeed each other in the circumferential direction. Via the cooling holes 232.1 and 232.2, radially outwards flowing cooling air can be guided to the stiffening rings 5.1 and 5.2. The cooling holes 232.1 and 232.2 thus make it possible to influence the temperature in the area of the stiffening structure 5a in a targeted manner. In particular in the area of the high-pressure turbine 13, the use of TiMMC is possible for the stiffening structure 5a through the air cooling of the stiffening structure 5a.

[0077] Just as in the embodiment variant of FIG. 1, in the embodiment variant of FIG. 2, a package solution with a stabileand in the case of the embodiment variant of FIG. 2 mutualaxial support of stiffening structures 5a, 5b of rotor blade assembly groups 2a, 2b is achieved.

[0078] In the embodiment variant of FIG. 2, stiffening structures 5a and 5b with respectively two stiffening rings 5.1 and 5.2 are respectively provided at two rotor blade assembly groups 2a and 2b axially succeeding one another, wherein in particular two opposite stiffening rings 5.2 and 5.1 of the two rotor blade assembly groups 2a and 2b are supported and axially secured against each other via an intermediate barrier element 6.2.

[0079] Here, the barrier element 6.2 is again provided at the flange connection 7.2 in the area of the flange sections 230a and 240a. However, in contrast to the embodiment variant of

[0080] FIG. 1, two axially protruding barrier element sections 62a and 62b extending opposite to one another project at the base 62c of the barrier element 6.2 of FIG. 2, so that the barrier element 6.2 is T-shaped in cross-sectional view.

[0081] While a first barrier element section 62a extends in the direction of the rear stiffening ring 5.2 of the first rotor blade assembly group 2a, the other, second barrier element section 62b extends axially in the direction of the frontal stiffening ring 5.1 of the second rotor blade assembly group 2b. When the two rotor blade assembly groups 2a and 2b are affixed at each other in this manner, the two opposite stiffening rings 5.2 and 5.1 and consequently the stiffening structures 5a and 5b formed with them are axially secured against each other by means of an individual common barrier element 6.2.

[0082] Incidentally, also in the embodiment variant of FIG. 2, the frontal stiffening ring 5.1 of the frontal rotor blade assembly group 2a, is axially secured against a barrier element 6.1 of the flange section 206a. The rear stiffening ring 5.2 of the rear rotor blade assembly group 2b is in turn axially secured by means of a dedicated third barrier element 6.3 which is fixated with a flange section 240b of the blade carrier 24 of the further rotor blade assembly group 2b. Via a flange connection 7.3, this (rear) flange section 240b is connected in a torque-proof manner to a flange section 206b at which the barrier element 6.3 is formed with a radially outwards extending base 62c and a barrier element section 62b that protrudes axially in the direction of the stiffening ring 5.2.

[0083] In the embodiment variant of FIG. 3, an axial securing is provided for the frontal stiffening ring 5.1 via a blade-carrier-side barrier element 236, by way of example. This barrier element 236 is formed at the blade carrier 23 of the rotor blade assembly group 2a and extends radially inwards with at least one barrier element section 60a, 60b to engage around the stiffening ring 5.1 in a form-fit manner at a radially outer edge.

[0084] As shown in the combined view of FIGS. 4, 5, 6 and 6A, the barrier element 236 can extend in a circular or circular-segment-shaped manner about the central axis M and along can comprise multiple barrier element sections 60a, 60b along a circumferential direction about the central axis M. These barrier element sections 60a, 60b engage around the stiffening ring 5.1 at multiple locations along the circumference in such a manner that, in the assembled state of the rotor blade assembly group 2a according to the intended use, multiple securing sections of the stiffening ring 5.1 in the form of respectively one radially protruding securing notch 50a to 50d are received between a barrier element section 60a, 60b and the carrier section 231.

[0085] The barrier element 236 of the blade carrier 23 shown in more detail in FIGS. 4 to 6A has respectively one gap 61a, 61b or 61c between the barrier element sections 60a and 60b that are arranged in a manner distributed along the circumference, extending radially and axially with respect to the central axis M. Into these gaps 61a to 61c, respectively one securing notch 50a to 50d of the stiffening ring 5.1 can be inserted during mounting of the stiffening structure 5a at the blade carrier 23. For this purpose, each radially outwards protruding securing notch 50a to 50d is dimensioned to be smaller than a respective gap 61a to 61c of the blade-carrier-side barrier element 236. The stiffening ring 5.1 can thus be arranged in an axial direction R1 (cf. FIG. 4) at the blade carrier 23, so that the stiffening ring 5.1 abuts at the fir-tree-shaped profile of the connecting area 231 of the blade carrier 23 in a form-fit manner at the one face side of the blade carrier 23, and with its securing notches 50a to 50d is received in the gaps 61a to 61c of the barrier element 236. The stiffening ring 5.1 is thus initially present at the blade carrier 23 in a defined mounting position.

[0086] For axial securing of the stiffening ring 5.1 at the blade carrier 23, the stiffening ring 5.1 is subsequently rotated into a barrier position along a circumferential direction R2 relative to the blade carrier 23. By rotating the stiffening ring 5.1, the individual securing notches 50a to 50d respectively move into a groove or a gap 600 that is bordered by a barrier element section 60a, 60b of the barrier element 236. By introducing a securing notch 50a to 50d into the respective gap 600, a barrier element section 60a, 60b respectively engages around it, or the stiffening ring 5.1 engages around the barrier element sections 60a, 60b of the blade-carrier-side barrier element 236 via the securing notches 50a to 50d. The stiffening ring 5.1 is thus locked at the blade carrier 23 through rotation in the circumferential direction R2 in the kind of a bayonet joint.

[0087] To subsequently secure the stiffening ring 5.1 against axial twisting relative to the blade carrier 23 and thus to lock a barrier position taken by the stiffening ring 5.1, in which the stiffening ring 5.1 is connected to the barrier element 236 in a form-fit manner, at least one locking element in the form of a locking pin 8 is provided. This locking pin 8 is inserted in the axial direction R3 into a gap 61a, 61b or 61c between two barrier element sections 60a, 60b. Here, a shaft or spigot section 80 of the locking pin 8 meshes with multiple recesses 51a, 51b, 51c or 51d of the stiffening ring 5.1 that are respectively formed between two radially protruding securing notches 50a/50b, 50b/50c or 50c/50d. At the same time, the locking pin 8 meshes in a form-fit manner with a head 81, which is wider as compared to the shaft or spigot section 80, with the gap 61b of the barrier element 236 formed between two barrier element sections 60a, 60b.

[0088] If the locking pin 8 is inserted according to the intended use at the stiffening ring 5.1 and the barrier element 236 of the blade carrier 23, the shaft or spigot section 80 of the locking pin 8 e.g. meshes in a recess 51b of the stiffening ring 5.1 that is present in the gap 61b. The head 81 of the locking pins 8 is almost completely or completely received inside the gap 61b, and with a bottom side abuts a face side 510 of two adjacent securing notches 50b and 50c.

[0089] If the locking pin 8 is inserted, the stiffening ring 5.1 is blocked against twisting relative to the blade carrier 23 and thus relative to the blade-carrier-side barrier element 236. Only by removing the locking pin 8for example for maintenance or repair worktwisting of the stiffening ring 5.1 and thus its return into a mounting position, in which the stiffening ring 5.1 can be removed from the blade carrier 23, can be allowed.

[0090] To secure the locking pin 8 itself at the blade carrier 23 and in particular at the barrier element 236, a separately mountable securing element in the form of a securing bracket 9 is provided. At that, the securing bracket 9 with its U-shaped cross section is inserted into a gap-like receptacle 810 at the head 81 of the locking pin 8, if the locking pin 8 has been inserted at the barrier element 236 and the stiffening ring 5.1 in its barrier position according to the intended use. At that, the securing bracket 9 is inserted with a base 90 into the receptacle 810 of the locking pin 8 along an axial (mounting) direction R4. At that, spring-elastic bracket ends 91 and 92 protruding laterally from the base 90, are inserted behind adjacent barrier element sections 60a, 60b, so that the bracket ends 91 and 92 respectively engage behind one barrier section 60a or 60b. In this manner, the securing bracket 9 is arrested at the barrier element 236 and axially secures the locking pin 8 against being removed from the blade carrier 23. To illustrate this axial securing, FIG. 4 also shows a securing bracket 9 without a locking pin 8, for example.

[0091] Via an access opening 82 at the head 81 of the locking pin 8, the base 90 of the inserted securing bracket 9 can be accessed to be able to remove it from the locking pin 8, if needed.

[0092] For locking the stiffening ring 5.1 in the barrier position, a locking pin 8 with the securing bracket 9 inserted thereat may be sufficient. However, in principle multiple locking pins 8 distributed across the circumference can of course also be provided with a securing bracket 9 and inserted into respectively one of multiple gaps 61a to 61c provided at the ring-shaped circumferential barrier element 236.

[0093] In principle, for avoiding abrasion and wear, a coating can be provided at the surfaces of two components of a rotor blade assembly group 2a, 2b that are in contact with each other. Thus, for example a coating can in particular be provided at the connecting area 231, 241, e.g. at the fir-tree-shaped profile, and/or at a barrier element section 60a, 60b, 62a or 62b.

PARTS LIST

[0094] 11 low-pressure compressor [0095] 12 high-pressure compressor [0096] 13 high-pressure turbine [0097] 14 medium-pressure turbine [0098] 15 low-pressure turbine [0099] 20, 21, 22 rotor blade [0100] 200, 210, 220 blade root [0101] 206a, 206b flange section [0102] 23, 24, 25 blade carrier [0103] 230, 240, 250 carrier section [0104] 230a, 230b flange section [0105] 231, 241 connecting area [0106] 232.1, 232.2 cooling hole [0107] 236 barrier ring (barrier element) [0108] 2300 flange area [0109] 240a, 240b flange section [0110] 2a, 2b, 2c rotor blade assembly group [0111] 30, 31 guide vane [0112] 4.1, 4.2 flange connection [0113] 5.1, 5.2 stiffening ring (stiffening element) [0114] 500 MMC core [0115] 50a, 50b, 50c, 50d securing notch (securing section) [0116] 510 end face [0117] 51a, 51b, 51c, 51d recess [0118] 5a, 5b stiffening structure [0119] 6.1, 6.2, 6.3 barrier element [0120] 600 gap [0121] 60a, 60b barrier element section [0122] 61a, 61b, 61c gap [0123] 62a, 62b barrier element section [0124] 62c base [0125] 7.1, 7.2, 7.3 flange connection [0126] 8 locking pin (locking element) [0127] 80 shaft/spigot section [0128] 81 head [0129] 810 receptacle [0130] 82 access opening [0131] 9 securing bracket (securing element) [0132] 90 base [0133] 91, 92 bracket end [0134] A outlet [0135] B bypass channel [0136] BK combustion chamber section [0137] C outlet cone [0138] E inlet/intake [0139] F fan [0140] FC fan housing [0141] M central axis/rotational axis [0142] O1, O2 passage opening [0143] R entry direction [0144] R1, R2, R3, R4 direction [0145] S rotor shaft [0146] T turbofan engine (gas turbine engine) [0147] TT turbine [0148] V compressor