Bearing device for load reduction

Abstract

Bearing device (40) for a gas turbine engine (10), comprising: - a bearing (41); - a bearing support (42) holding the bearing (41), which is attached by a predetermined breaking device (43) to a connecting element (44) which can be connected to or is connected to a supporting structure (28) of the gas turbine engine (10); - a first toothed component (45) mounted on the bearing support (42); and - a second toothed component (46) fixed to the connecting element (44), wherein the first toothed component (45) and the second toothed component (46) can be brought into engagement with each other or are in such a way that one of the toothed components (45, 46) can roll on the other.

Description

[0001] The present disclosure relates to a bearing device for a gas turbine engine according to claim 1, to a gas turbine engine and to a method for manufacturing a bearing device according to claim 13.

[0002] If a bearing that movably supports one component against another is subjected to a force exceeding its intended load-bearing capacity, the bearing and adjacent parts can be damaged. In the case of a rotating bearing, such loads can be caused, for example, by an imbalance, especially a suddenly occurring imbalance.

[0003] The loss of a fan blade from a gas turbine engine during operation (a so-called fan blade-off event) is regularly accompanied by a particularly strong imbalance. This imbalance results in corresponding radial loads, especially on a bearing adjacent to the fan on the shaft driving the fan and on a load-bearing structure of the gas turbine engine. Gas turbine engines can be designed, for example, through the use of appropriate materials, to withstand such loads.

[0004] One way to reduce loads immediately after the loss of the fan blade is to use shear pins that connect the bearing to the supporting structure and break when a maximum load capacity is exceeded. A catch bearing, positioned offset from the main bearing, can then ensure the radial positioning of the shaft. This catch bearing is designed to be correspondingly robust to securely hold the shaft, which in turn increases the overall weight.

[0005] Another possible effect of such an arrangement is a change in the shaft's resonance frequency after the shear pins break. In many gas turbine engines, this frequency is in the range of the fan's rotational speed, known as windmilling, during aircraft flight. Windmilling refers to the turbine-like behavior of the fan, which is driven by air flowing through the engine. Resonance induced in this way can cause strong vibrations that stress not only the gas turbine engine but also its connection to the aircraft and the aircraft itself. This is countered, for example, by specific flight maneuvers after blade failure, fine-tuning the resonance frequency of other components, and using appropriate materials in the manufacture of structural parts.

[0006] The object of the present invention is to provide a bearing device that enables secure bearing, in particular of a shaft, at the lowest possible weight.

[0007] According to one aspect, a bearing device for a gas turbine engine is provided. The bearing device comprises a bearing (e.g., with a stator and a rotor rotatable relative to the stator). The bearing device further comprises a bearing bracket that holds the bearing (in particular, the stator, e.g., rigidly connected to the stator). The bearing bracket is rigidly connected by a predetermined breaking point to a connecting element, which is designed to be connected to, or optionally is connected to, a supporting structure of the gas turbine engine. The bearing device also comprises a first toothed component mounted (in particular, rotatably) on the bearing bracket and a second toothed component attached to the connecting element.The bearing device is designed in such a way that the first toothed component and the second toothed component can be brought into meshing engagement with each other after, or optionally as a result of, a destruction of the predetermined breaking device, such that one of the toothed components (in particular the first one) can roll on the other of the toothed components.

[0008] Each of the toothed components comprises a multitude of raised sections (arranged side by side, particularly in the circumferential direction). These raised sections are hereinafter also referred to as teeth, but are not limited to involute shapes or similar forms. For example, the teeth can also be triangular, trapezoidal, or semicircular.

[0009] By rolling the meshing components, it is possible, particularly through unequal numbers of teeth, to generate a relative circumferential movement between the two components. This relative movement can be used to reduce peak loads. Optionally, this relative movement, especially rotational movement, can be converted into axial movement via a thread or similar mechanism. This axial movement can then be used to re-establish a connection (e.g., a frictional one). With such a restored bearing configuration (e.g., after blade loss), the rotor's natural frequency changes, and the loads transmitted to the structure can be reduced. The bearing arrangement serves to reduce the load. Consequently, an optional catch bearing can be designed with less material, thus enabling reliable shaft support with a reduced overall weight.After the predetermined breaking point is destroyed, the bearing bracket is movable relative to the connecting element.

[0010] The first and second toothed components, for example, have a different number of teeth. Alternatively or additionally, relative circumferential movement with the same number of teeth can also be achieved through a corresponding tooth design. For example, the first toothed component has fewer teeth than the second, perhaps at least one fewer tooth. If the predetermined breaking point is destroyed by an imbalance in a shaft supported by the bearing assembly, this imbalance can lead to an orbiting motion of the shaft. This orbiting motion, in particular, can cause one toothed component to roll against the other. Due to the different number of teeth, the toothed components are set into rotation relative to each other. This rotation can be in the opposite direction to the orbiting motion.Friction resulting from this rotation can further reduce peak loads.

[0011] Optionally, the first toothed component is designed as a gear with external teeth, and the second toothed component as a ring gear with internal teeth. The gear can be located inside the ring gear.

[0012] In one embodiment, the first toothed component is mounted on the bearing holder via a thread and thus engages with it. By rotating the first toothed component relative to the bearing holder (especially by rolling the first toothed component against the second toothed component), it can be screwed along the thread. This allows an imbalance (e.g., resulting from a fan blade-off event) to be used to displace the first toothed component axially (with respect to the rotational axis of the bearing rotor, relative to the bearing stator). In other words, any resulting relative circumferential movement of the two toothed components can be converted into an axial movement of one component, which can be used to close a radial gap.

[0013] In a further development, a holder supporting the first toothed component engages with the bearing mount via the thread. The holder and the first toothed component can be integral or connected. The holder can have a stop. The connecting element can have a counter-stop. The bearing assembly can be designed such that, with an intact predetermined breaking point, there is (especially radial) play between the stop and the counter-stop. Optionally, the (especially radial) play between the stop and the counter-stop can be changed by a screw movement of the holder relative to the bearing mount along the thread. Thus, it is possible to use the orbiting motion to change the amount of play.

[0014] In a further development, the holder's stop can be engaged by the screw movement relative to the bearing mount along the thread against the counter-stop. In this way, it is particularly possible to fix two components relative to each other that would otherwise be movable after the predetermined breaking point has been destroyed.

[0015] Optionally, the bearing bracket can be fixed in place by striking the stop against the counter-stop on the connecting element. This allows the bearing assembly to absorb the maximum load peaks after an exceptional event (e.g., the loss of a fan blade) by breaking the predetermined breaking point. After a period of time, the initially movable bearing bracket can then be firmly reconnected to the connecting element. In a gas turbine engine, the rotational speed of the supported shaft typically decreases during this period, particularly due to a fuel supply shutdown. After the radial loads have decreased (and optionally before a renewed increase due to resonance during windmilling), the bearing bracket and the connecting element are re-secured. This ensures particularly reliable shaft support.Furthermore, an optional retaining bearing only needs to hold the shaft for a short period and can therefore be manufactured and installed with less material. This period is also adjustable, particularly by the number of teeth on the geared components and the geometric dimensions of the thread (especially tooth shape and geometry, thread pitch, and thread length). Thus, these parameters can be adapted or adjustable to the specific gas turbine engine. Fixing the bearing holder to the connecting element also includes fixing it with a remaining gap, as long as forces can be transmitted (continuously) via the resulting load path. Alternatively, complete fixing with the gap closed is also possible.

[0016] In a further development, the stop and / or counter-stop are conically shaped, specifically such that the respective cone is aligned concentrically to the central axis of rotation of the gas turbine engine. This allows for a gradual reduction of play between the stop and the counter-stop. The bearing support can be (re)centered by the conical design of the stop and / or counter-stop. Furthermore, this design enables gentle fixing of the bearing support. The centering can, in particular, lead to the bearing returning to its original position. This allows the natural frequency of the supported shaft to be changed, specifically so that it lies sufficiently far outside the excitation frequency caused by windmilling.

[0017] Alternatively or additionally, the toothed components are each conically shaped. This makes it possible, for example, to maintain the engagement of the toothed components even when the bearing mount is continuously centered and the radial deflection decreases.

[0018] Optionally, the cone described by the first and / or the second toothed component has an opening angle that is less than or equal to the opening angle of the cone described by the stop and / or the counter-stop. However, embodiments are also conceivable in which the cone described by the first and / or the second toothed component has an opening angle that is greater than the opening angle of the cone described by the stop and / or the counter-stop.

[0019] In one embodiment, the bearing device includes a lubricant supply. This supply can be configured to provide lubricant, particularly between the holder and the bearing mount, to the thread. This allows the holder to be screwed along the thread with exceptional ease and prevents seizing during normal operation.

[0020] According to one aspect, a gas turbine engine is provided, in particular a gas turbine engine for an aircraft. The gas turbine engine comprises at least one bearing device according to any embodiment described herein. The gas turbine engine may further comprise a fan driven by a shaft of the gas turbine engine. The bearing of the bearing device may rotatably support the shaft.

[0021] This allows for the provision of a gas turbine engine that, despite its low weight, enables secure shaft support. By reconnecting the bearing to the supporting structure of the gas turbine engine, an aircraft with this engine can remain safely airborne for a comparatively long period even after a fan blade-off event, without experiencing severe vibrations or loads.

[0022] According to one aspect, a method for manufacturing a bearing device for a gas turbine engine is provided, in particular for manufacturing a bearing device according to any embodiment described herein. The method comprises the following steps (optional, but not necessarily in this order): First step: Providing a bearing (with a stator and a rotor rotatable therewith) and a bearing support holding the bearing, which is attached by a predetermined breaking device to a connecting element that can be connected to, or is connected to, a supporting structure of the gas turbine engine. Second step: Mounting a first toothed component on the bearing support such that, upon destruction of the predetermined breaking device, the first toothed component and a second toothed component fixed to the connecting element can be brought into engagement with each other, or are in engagement, such that one of the toothed components can roll on the other.

[0023] In one embodiment of the second step, the first toothed component is mounted on the bearing holder by means of a thread. The method can further include the following steps: - Specifying a time period from the point of destruction of the predetermined breaking point, in particular until the intended fixing of the bearing holder to the connecting element; - Optional: Specifying a rotor speed relative to the stator and / or a precession frequency; and - Determining the number of teeth on the first toothed component, the number of teeth on the second toothed component, and the geometric dimensions (e.g., number of revolutions and / or shape, thread pitch, and thread length) of the thread such that, after the predetermined breaking point is destroyed, a stop fixed to the first toothed component strikes a counter-stop fixed to the bearing support after a time interval corresponding to the specified time interval. Particularly precise adjustments are possible by taking into account the specified rotor speed and / or precession frequency. - Optional: Design of the teeth (e.g., involute, semicircular, trapezoidal, or triangular) of the toothed components and / or a conically shaped stop and counter-stop and / or the size of a radial gap that (optionally by means of a stop on a catch bearing) determines movement after the predetermined breaking device is destroyed. These designs can be adapted to a specific gas turbine engine.

[0024] Afterwards, the first toothed component, the second toothed component, a holder and / or the bearing holder can be designed and provided with the determined number of teeth and / or revolutions (and a corresponding clearance).

[0025] This allows for a reconnection of the bearing that is adapted to a specific gas turbine engine, thus enabling overload protection to be particularly reliable.

[0026] It is understood by a person skilled in the art that a feature or parameter described in relation to one of the aspects above can be applied to any other aspect, provided they are not mutually exclusive. Furthermore, any feature or parameter described here can be applied to any aspect and / or combined with any other feature or parameter described here, provided they are not mutually exclusive.

[0027] Exemplary embodiments are now described with reference to the figures; the figures show: Fig. 1 a side section view of a gas turbine engine; Fig. 2 a side-section close-up view of part of the gas turbine engine with a bearing device; Fig. 3 a cross-sectional view of a gear and a toothed ring of the bearing device of the gas turbine engine; Fig. 4. A method for manufacturing a bearing device for a gas turbine engine: and Fig. 5 a schematic diagram of loads on a shaft after the loss of a fan blade of a gas turbine engine.

[0028] Fig. 1 represents a gas turbine engine 10 with a main axis of rotation 9 The gas turbine engine 10 includes an air intake 12 and a fan 23 , which generates two air streams: a core air stream A and a bypass airflow B The gas turbine engine 10 includes a core engine 11 , which the core airflow A absorbs. The core engine 11 In axial flow sequence, it includes a compressor 14(optionally subdivided into low-pressure compressors and high-pressure compressors), a combustion device 16 , a high-pressure turbine 17 , a low-pressure turbine 19 and a core thrust nozzle 20 An engine nacelle 21 surrounds the gas turbine engine 10 and defines a bypass channel 22 and a bypass thrust nozzle 18 The bypass airflow B flows through the bypass channel 22 The fan 23 is over a wave 26 at the low-pressure turbine 19 It is attached and powered by it.

[0029] During operation, the core airflow A through the compressor 14 accelerated and compressed. The air from the compressor 14 The expelled compressed air is fed into the combustion unit. 16The gas is then piped to where it is mixed with fuel and the mixture is burned. The resulting hot combustion products then spread through the high-pressure and low-pressure turbines. 17 , 19 and thereby drive them, before they pass through the nozzle to provide a certain thrust. 20 be expelled. The high-pressure turbine 17 drives the compressor 14 through a suitable connecting shaft 27 on. The fan 23 generally provides the main part of the thrust.

[0030] Other gas turbine engines to which the present disclosure may apply may have alternative configurations. For example, such engines may have an alternative number of compressors and / or turbines and / or an alternative number of connecting shafts. As another example, the [reference to be added] Fig. 1 Gas turbine engine shown, a split flow nozzle20 , 22 on, which means that the current flows through the bypass channel 22 it has its own nozzle, which is separate from the engine core nozzle 20 separate and radially outside of it. However, this is not limiting and any aspect of the present disclosure may also apply to engines in which the flow through the bypass channel 22 and the current through the core 11 The air is mixed or combined upstream of (or before) a single nozzle, which may be referred to as a mixing-flow nozzle. One or both nozzles (whether mixing-flow or split-flow) may have a fixed or variable area. Although the described example relates to a turbofan engine, the disclosure may be applied, for example, to any type of gas turbine engine, such as an open-rotor engine (where the fan stage is not surrounded by an engine nacelle) or a turboprop engine.

[0031] The geometry of the gas turbine engine 10 and its components are defined by a conventional axis system that has an axial direction (pointing towards the axis of rotation). 9 is aligned), a radial direction (in the direction from bottom to top in Fig. 1) and a circumferential direction (perpendicular to the view in Fig. 1) includes. The axial, radial and circumferential directions are perpendicular to each other.

[0032] The gas turbine engine 10 includes a storage device 40 . By means of the bearing device 40 is the wave 26 (which the fan 23 (drives) on a supporting structure 28 of the gas turbine engine 10 It is mounted on a rotating bearing. The supporting structure is located, for example, on the engine nacelle. 21 fastened. The bearing device 40 has several bearings, in the present example three bearings 41 , 52 ,53 A camp 41 is adjacent to the fan 23 arranged. This camp 41 In the present example, it is designed as a fixed bearing, meaning it can transmit axial forces, whereby the bearing 41 It can also be designed as a loose bearing. A further bearing is arranged downstream of it. 52 is designed as a holding camp. This camp 52 is trained to the wave 26 to store safely if it is adjacent to the fan 23 arranged storage 41 from the supporting structure 28 is separated, e.g. by the loss of a fan shovel of the fan 23 during the operation of the gas turbine engine 10 . To her fan 23 The wave is at the far end. 26 with a third storage area 53 on the supporting structure 28 Rotatable bearing. This bearing 53 It features, for example, cylindrical roller elements.

[0033] Fig. 2 shows in particular the fan 23 neighboring camps 41 as well as other elements of the storage device 40 .

[0034] The warehouse 41 includes a component that is relative to the supporting structure 28 is fixed. This component will be referred to below as the stator. 41a denoted. In the present example, the stator is called. 41a a bearing outer ring. Furthermore, the bearing includes 41 a component that is relative to the supporting structure 28 It is rotatable. This component will subsequently be referred to as the rotor. 41b The rotor is described as follows: 41b is attached to a fixed point on the wave 26 connected connecting element 26a the wave 26 fastened. The bearing 41 includes several rolling elements; in the example shown, the bearing 41 A ball bearing. It comprises balls arranged in a cage that support the rotor. 41b rotatable within the stator41a store.

[0035] The stator 41a is firmly attached to a bearing bracket 42 The stator is mounted, in this case via two axially projecting flanges, although a one-piece design is also conceivable. 41a is within the bearing bracket 42 arranged. The bearing bracket 42 is equipped with a predetermined breaking device 43 on a connecting element 44 attached, in the example shown via a radially outwardly projecting (disc-shaped) section of the bearing bracket 42 The bearing bracket 42 and the predetermined breaking device 43 and the connecting element 44 They can be formed as a single piece or alternatively mounted together. The predetermined breaking point 43 The example shown includes a large number of shear pins. 43a, which fail when a predetermined (especially radial) load is exceeded, e.g., break. The shear pins 43a extend in an axial direction. The connecting element 44 is at the in Fig. 2 supporting structures not shown 28 of the gas turbine engine 10 permanently mounted (see Fig. 1) Optionally, the connecting element 44 part of the supporting structure 28 dar.

[0036] The storage device 40 further includes a gear transmission with a first toothed component, here in the form of an externally toothed gear. 45 , and a second toothed component, here in the form of an internally toothed gear ring 46 The gear 45 is in the gear ring 46 recorded. The gear ring 46 is at the connecting element 44Attached (alternatively integrally with it or formed with a part of it), in the example shown to an axially projecting (conical) ring section. The ring section is optionally supported by several circumferentially distributed stiffening ribs (in Fig. 2 illustrated by a dashed line).

[0037] The gear 45 is on a holder 47 attached (alternatively formed as one piece with it or a part thereof). The holder 47 The example shown has a section with a V-shaped cross-section. In the Fig. 2. State shown with intact shear device 23 is a head circle of the gear 45 from a base circle of the gear ring 46 spaced apart. In this state, no radial loads are transmitted via the gear drive.

[0038] Fig. 3 shows the gear ring 46 and the gear included therein 45The gear 45 has a smaller number of teeth than the toothed ring 46 , so at least one less tooth. In the example according to Fig. 3 includes the gear 45 49 teeth, the toothed ring 46 51 teeth. The gear 45 has a smaller pitch circle diameter than the gear ring 46 The gear 45 can be on the inside of the gear ring 46 roll. Lubrication (active or passive) of the tooth flanks is optional.

[0039] In the condition according to Fig. 2 with intact shear pins 43a is the gear 45 concentric to the toothed ring 46 arranged. The shear pins break. 43a as a result of an overload caused by an imbalance, the bearing bracket 42 movable relative to the connecting element 44 The radial loads cause the gear to become misaligned. 45 in combing engagement (and contact) with the tooth ring 46 If the warehouse41 from the supporting structure 28 Once torn away, the wave leads 26 As a result of the imbalance, an orbiting motion similar to a precession develops. Thus, the wave serves a purpose. 26 as an eccentric for the gear drive. The orbiting shaft causes a rotating motion of the gear. 45 on the gear ring 46 During this movement, the gear rotates. 45 relative to the gear ring 46 .

[0040] As particularly evident Fig. 2. The bearing bracket can be identified. 42 with a thread 42a provided, in this case with an external thread. This thread 42a is the holder 47 with a suitable thread 47a , here screwed onto an internal thread. A destructible lock. 50 prevents the holder 47 during normal operation (before an overload event) of the gas turbine engine 10 at a rotation relative to the bearing mount 42(e.g. by axially protruding teeth that align with the holder) 47 and the bearing bracket 42 are under intervention). The blockage 50 It serves as an anti-rotation component. Alternatively or additionally, the lock secures 50 the holder 47 axial. As soon as the gear 45 on the gear ring 46 as a result of an overload, the lock breaks. 50 and causes the holder to rotate. 47 relative to the bearing bracket 42 free. The thread 42a is oriented in such a way that the rolling motion of the gear is determined by the direction of the orbiting motion. 45 the holder 47 in the direction of the connecting element 44 screws.

[0041] The holder 47 indicates one of the connecting element 44 facing (outer circumferential) cone, which serves as a stop 47b serves as a connecting element. 44It also features a cone. In this case, it is formed around the inside and serves as a stop. 47b as a counterattack 44a The opening angles of both cones are the same, so the stop 47b and the counterattack 44a (by a sufficiently wide screw movement of the holder) 47 ) can be brought together in a flat arrangement. This ensures good load transfer - another form of contact between the counter-stop. 44a and the attack 47b However, that's also conceivable. In this case, the centering point is on the thread. 42a the bearing bracket 42 brackets screwed along 47 the camp 41 A radial game S between the attack 47b and the counterattack 44a It gets smaller until the stop 47b and the counterattack 44a to be arranged together in a flat, continuous system. Furthermore, the holder47 between the bearing bracket 42 and the connecting element 44 (specifically the conical part) is clamped in place. A complete positive fit is possible, but not absolutely necessary. The catch bearing would also be relieved of stress even with a remaining gap. This gap can be lubricated, as the conical stop 47b in the conical counterattack 44a would rotate. The bearing 41 It is then fixed again.

[0042] An end section of the thread 42a the bearing bracket 42 It may be roughened, have a friction-enhancing coating, or be different from the rest of the thread. 42a They may have a different slope and / or be geometrically different in some other way. This causes the holder to rotate. 47 on the thread 42a fixed in the final position (e.g. by plastic deformation), so that unintentional loosening is avoided.

[0043] To prevent the gear from 45 and the gear ring 46 If, during progressive centering, these become outside the scope of the process, they also exhibit a conical shape, as is particularly evident in... Fig. Figure 2 illustrates this. The opening angle is more acute than that of the cones. Optionally, the opening angle of the gear is... 45 and gear 46 dimensioned so that they are disengaged by the centering when the stop 47b in a flat layout with the counterattack 44a device or shortly before, when the game S is already negligibly small.

[0044] The warehouse 41 It is continuously supplied with lubricant (in this case, oil). A lubricant channel is located in Fig. 2 on the radially outer side of the stator 41a to be seen. From there, a lubricant supply extends in the form of a channel. 48 for oil towards the engaged threads42a , 47a This way, lubricant is applied between the threads. 42a , 47a pressed so that the holder 47 In case of overload, unimpeded movement against the connecting element 44 It can be screwed in. To prevent lubricant loss during normal operation, the bearing assembly includes 40 several sealing elements 49 e.g., O-rings. Each one is a sealing element. 49 is at both axial ends of the thread 42a arranged and seals the holder 47 opposite the bearing bracket 42 off. The sealing elements 49 Additionally, the holder may rattle. 47 on the bearing bracket 42 and wear of the threads 42a , 47a reduce or prevent.

[0045] Alternatively or in addition to a lubricant supply, the following can be used during the assembly of the bearing device: 40A passive lubricant should be applied, especially to the thread. 42a the bearing bracket 42 .

[0046] The gear drive, the stop 47b and the counterattack 44a are enclosed by a lubricant tray. These parts are (via the bearing) 41 and / or a squeeze film damper) supplied with lubricant. This eliminates any remaining play. S between attack 47b and counterattack 44a The seal is lubricated, allowing for better transmission of radial loads and preventing local overheating. The lubricant also dampens vibrations. Optionally, the clearance is adjusted. S The gap formed is directly supplied with lubricant.

[0047] On its surface, the attack 47b The holder points to the opposite side. 47 optional stiffening ribs on, in Fig. 2 is illustrated by means of a dashed line. Similarly, the connecting element 44 on the surface of the counterattack 44a Optional stiffening ribs are located on the opposite side.

[0048] Fig. Figure 4 shows a method for manufacturing the bearing device 40 according to Fig. 1 to Fig. 3.

[0049] First, in a first step S1 A time period is specified after the destruction of the predetermined breaking point (e.g. 10 seconds for some types of gas turbine engines).

[0050] In a second step S2 The rotational speed of the rotor will be 41b (especially the rotational speed profile after blade loss) or parameters related to rotational speed (e.g., a typical airspeed) relative to the stator 41b and / or an orbiting or precession frequency of the wave 26 specified.

[0051] In a third step S3 The number of teeth, in particular a tooth ratio and / or a tooth difference of the gear, are determined based on the rotational speed of the rotor (the curve) and / or the orbiting / precession frequency. 45 and gear 46 , and the geometric dimensions of the thread 42a , 47a (Tooth shape and tooth geometry, thread pitch and length) determined in such a way that after destruction of the predetermined breaking point 43 which is firmly attached to the gear 45 combined attack 47b after a period of time, firmly attached to the bearing bracket 42 associated counterattack 44a The impact time is equal to the specified time interval. To increase (or decrease) the time interval, the number of thread turns can be increased (decreased), for example. The axial and radial loads resulting from the impact of the cone are taken into account in the thread design.

[0052] In a fourth step S4 will the gear 45 , the gear ring 46 , the holder 47 and the bearing bracket 42 with the determined number of teeth and / or the geometry of the thread 42a trained.

[0053] The steps S1 until S4 are optional, especially for the best possible adaptation to a given gas turbine engine 10 .

[0054] In a fifth step S5 will the camp 41 (with the stator 41a and the rotatable rotor 41b) and the stator 41a holding bearing bracket 42 , which are caused by the predetermined breaking point 43 at the connecting element 44 is attached, provided (especially according to the steps S1 until S4 ), wherein at the connecting element 44 the gear ring 46 is determined or will be determined.

[0055] In a sixth step S6 will the gear 45 so on the bearing bracket 42 arranged so that it is mounted on it, in such a way that the gear 45 and the gear ring 46 by destroying the predetermined breaking device 43 can be brought into engagement with each other, so that the gear 45 on the gear ring 46 can roll off and is held in its axial position relative to the gear ring by the thread 46 shifts. This results in the centering and reconnection of the bearing. 41 with the supporting structure 28 .

[0056] Fig. Figure 5 schematically illustrates the radial loads resulting from the loss of a fan blade during the operation of an exemplary gas turbine engine. A dashed line represents a comparative case in which the fan bearing lacks a predetermined breaking point. Starting at the highest rotational speeds, very high loads are transferred via the bearing into the supporting structure. Due to the rigid connection, the imbalance resulting from the blade loss has a significant impact, even with the successively decreasing rotational speed (due to engine shutdown after the blade loss).

[0057] In comparison, the solid line represents a case with a predetermined breaking point. Due to the destruction of the predetermined breaking point, the radial loads introduced into the supporting structure are significantly lower. However, due to the loosening of the bearing adjacent to the fan, the shaft exhibits a different resonant frequency compared to normal operation. This leads to [various effects] at lower speeds according to [specific example / method]. Fig. 5. This leads to a renewed increase in radial loads, particularly in the form of strong vibrations. In many cases, the resonant frequency lies within the range of those rotational speeds typically reached in flight due to the air pressure against the fan of the deactivated gas turbine engine (e.g., in the range of 20 to 30 Hz for some gas turbine engines).

[0058] Through the bearing device described above 40 , the gas turbine engine 10 with such a storage device 40for load reduction and the method for manufacturing the bearing device 40 Is it possible to store the warehouse? 41 After the shear pins are cut, they reconnect to the supporting structure at a later time. 28 to connect and thus change the resonant frequency again, in particular to increase it (optionally to the previous value). Appropriate timing can enable particularly low loads. This is achieved especially through the number of thread turns. 42a The time until reconnection is adjustable. This allows the bearing to be used for other purposes. 41 the slowing wave 26 after the strongest loads have subsided and before reaching the resonance range (e.g. at the point of the vertical, dashed line in Fig. 5) centered and attached to the supporting structure 28 to be fixed. As a result, it is possible to secure the catch camp. 52 and / or parts of the supporting structure 28to construct it with less material and thereby the shaft 26 to store particularly safely.

[0059] It is understood that the invention is not limited to the embodiments described above and that various modifications and improvements can be made without deviating from the concepts described herein. Any of the features can be used separately or in combination with any other features, provided they are not mutually exclusive, and the disclosure extends to and includes all combinations and subcombinations of one or more features described herein.

[0060] In particular, the warehouse 41 It could be a fixed storage area or a loose storage area. Alternatively or additionally, it could also be another type of storage area. 52 , 53 the wave 26 with the clutch 45 and the locking device46 to be provided, alternatively or additionally a bearing of another shaft of the gas turbine engine 10 e.g. the connecting shaft 27 . Reference symbol list 9 Main axis of rotation 10 Gas turbine engine 11 Core engine 12 Air intake 14 compressors 16 Combustion unit 17 High-pressure turbine 18 Bypass thrust nozzle 19 Low-pressure turbine 20 Core thrust nozzle 21 Engine nacelle 22 Bypass channel 23 Fan 26 wave 26a Connecting element 27 Connecting shaft 28 supporting structures 40 Storage device 41 warehouses 41a Stator 41b Rotor 42 Bearing bracket 42a thread 43 Breakaway device 43a Shear pin 44 Connecting element 44a Counterattack 45 Gear (first toothed component) 46 Gear ring (second toothed component) 47 holders 47a thread 47b attack 48-channel (lubricant supply) 49 Sealing element 50 suspension 52 bearings (catch bearings) 53 warehouses A core airflow B Bypass airflow S game

Claims

[1] Bearing device (40) for a gas turbine engine (10), comprising: - a warehouse (41); - a bearing support (42) holding the bearing (41), which is attached by a predetermined breaking device (43) to a connecting element (44) which can be connected or is connected to a supporting structure (28) of the gas turbine engine (10), - a first toothed component (45) mounted on the bearing support (42); and - a second toothed component (46) fixed to the connecting element (44), wherein the first toothed component (45) and the second toothed component (46) can be brought into engagement with each other or are positioned after destruction of the predetermined breaking device (43) in such a way that one of the toothed components (45, 46) can roll on the other. [2] Bearing device (40) according to claim 1, wherein the first toothed component (45) has a different number of teeth than the second toothed component (46). [3] Bearing device (40) according to claim 1 or 2, wherein the first toothed component (45) is designed as a gear and the second toothed component (46) is designed as a ring gear. [4] Bearing device (40) according to one of the preceding claims, wherein the first toothed component (45) is mounted on the bearing support (42) via a thread (42a). [5] Bearing device (40) according to claim 4, wherein a holder (47) supporting the first toothed component (45) engages with the bearing support (42) via the thread (42a) and has a stop (47b), wherein the connecting element (44) has a counter-stop (44a) and a clearance (S) between stop (47b) and counter-stop (44a) can be changed by a screwing movement of the holder (47) relative to the bearing support (42). [6] Bearing device (40) according to claim 5, wherein the stop (47b) of the holder (47) can abut the counter stop (44a) by a screwing movement relative to the bearing holder (42) along the thread (42a). [7] Bearing device (40) according to one of claims 5 or 6, wherein the bearing holder (42) can be fixed by striking the stop (47b) against the counter stop (44a) on the connecting element (44). [8] Bearing device (40) according to one of claims 5 to 7, wherein the stop (47b) and the counter-stop (44a) are each conically shaped. [9] Bearing device (40) according to one of the preceding claims, wherein the first toothed component (45) and the second toothed component (46) are each conically shaped. [10] Bearing device (40) according to claim 8 and claim 9, wherein the cone described by the first toothed component (45) and / or the second toothed component (46) has an opening angle that is less than or equal to an opening angle of the cone described by the stop (47b) and / or the counter stop (44a). [11] Bearing device (40) according to one of the preceding claims, insofar as it relates back to claim 4, further comprising a lubricant supply (48) which is configured to provide lubricant to the thread (42a) and / or into a gap to be closed. [12] Gas turbine engine (10), in particular for an aircraft, comprising a fan (23), a shaft (26) with which the fan (23) can be driven, and a bearing device (40) according to one of the preceding claims, wherein the bearing (41) of the bearing device (40) supports the shaft (26). [13] Method for manufacturing a bearing device for a gas turbine engine (10), in particular a bearing device (40) according to any one of claims 1 to 11, comprising the following steps: - Providing (S5) a bearing (41) and a bearing support (42) holding the bearing (41), which is attached by a predetermined breaking device (43) to a connecting element (44) which can be connected or is connected to a supporting structure (28) of the gas turbine engine (10), - Bearing (S6) a first toothed component (45) on the bearing holder (42) such that by destroying the predetermined breaking device (43) the first toothed component (45) and a second toothed component (46) fixed to the connecting element (44) can be brought into engagement with each other or are positioned so that one of the toothed components (45, 46) can roll on the other. [14] Method according to claim 13, wherein the first toothed component (45) is mounted on the bearing holder (42) via a thread (42a) and the method further comprises the following steps: - Specifying (S1) a time period after the destruction of the predetermined breaking device; - Determining (S3) a number of teeth of the first toothed component (45), a number of teeth of the second toothed component (46) and geometric dimensions of the thread (42a) such that, after destruction of the predetermined breaking device (43), a stop (47b) fixedly connected to the first toothed component (45) will strike a counter-stop (44a) fixedly connected to the bearing holder (42) after a time interval corresponding to the specified time interval.

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