Damper systems for engine shafts

Abstract

An engine assembly (10) defines an axial direction (A) and includes a gearbox (45), an engine core (20) including at least one rotor (15), and a flexible coupling shaft (100) having a first end (511) and a second end (512) along the axial direction (A). The first end (511) of the flexible coupling shaft (100) is connected to the engine core (20), and the second end (512) of the flexible coupling shaft is connected to the gearbox (45). A damper system (560, 560') is positioned at the second end (512) of the flexible coupling shaft (100). The damper system (560, 560') is configured to reduce vibrations of the flexible coupling shaft (100) during operation of the engine assembly (10).

Description

Technical Field

[0001] The present disclosure relates generally to turbine engines. In particular, the present disclosure relates to a damper system for an engine shaft of a turbine engine. Background Art

[0002] Turbine engines are continually challenged to improve efficiency in relation to performance, fuel consumption, and noise output, while generally maintaining or reducing the turbine engine package (e.g., axial or radial dimensions). One solution to improving turbine engine efficiency is to introduce a reduction gearbox or power gearbox between the engine core and the fan or propeller, such as in some turboprop, turboshaft, and turbofan turbine engine configurations. BRIEF DESCRIPTION OF THE DRAWINGS

[0003] The foregoing and other features and advantages will become apparent from the following more particular description of various exemplary embodiments, as illustrated in the accompanying drawings, in which like reference numerals generally indicate identical, functionally similar, and / or structurally similar elements.

[0004] Figure 1 A cross-sectional view of a system for connecting a gearbox to an engine core in a turbine engine is shown according to one embodiment of the present disclosure.

[0005] Figure 2 A system for connecting a gearbox to an engine core in a turbine engine according to another embodiment of the present disclosure is shown.

[0006] Figure 3 A gearbox for connection to an engine core of a turbine engine is shown according to one embodiment of the present disclosure.

[0007] Figure 4 A system for connecting a gearbox to an engine core in a turbine engine is shown according to one embodiment of the present disclosure.

[0008] Figure 5 Shown Figure 4 , which has a partially cutaway cross-sectional view of a gearbox according to an embodiment of the present disclosure.

[0009] Figures 6A to 6E Components of a sun gear system are shown according to an embodiment of the present disclosure.

[0010] Figure 7 Shown is a cross-sectional view of an arrangement in a turbine engine for connecting a gearbox to an engine core via a shaft including a damper system according to one embodiment of the present disclosure.

[0011] Figure 8A and 8BAn embodiment according to the present disclosure is shown Figure 7 An enlarged partial cross-sectional view of the damper system shown in FIG.

[0012] Figure 9A and 9B An enlarged partial cross-sectional view of a damper system according to another embodiment of the present disclosure is shown.

[0013] Figure 10A An oil distributor for use in a damper system according to an embodiment of the present disclosure is shown.

[0014] Figure 10B An embodiment according to the present disclosure is shown Figure 10A A partial cross-sectional view of the oil distributor shown in FIG.

[0015] Figure 11 is a flow chart outlining a method of connecting a gearbox to an engine core according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0016] According to the following detailed description, drawings and claims, the features, advantages and embodiments of the present disclosure are set forth or apparent.In addition, it should be understood that the following detailed description is exemplary and is intended to provide further explanation without limiting the scope of the present disclosure as claimed.

[0017] Various embodiments are discussed in detail below. Although specific embodiments are discussed, this is for illustrative purposes only. Those skilled in the relevant art will recognize that other components and configurations may be used without departing from the spirit and scope of the present disclosure.

[0018] The present disclosure relates to a system and method for connecting a turbine engine gearbox and an engine core. The system includes a flexible coupling shaft that connects a reduction gearbox or power gearbox of a fan or propeller assembly to the engine core. The flexible coupling shaft typically includes a fastening or fixed arrangement to the rotor of the engine core and a flexible arrangement for coupling to the gearbox. The flexible coupling shaft typically provides axial and / or radial deformation of the shaft while maintaining connection to the engine core and gearbox and necessary movement of the engine core and gearbox. According to one embodiment, the shaft is flexible in that only one end of the shaft is fixed (or immovable) to the engine core via, for example, mechanical fasteners, while the other end of the shaft, which contacts, for example, the sun gear system, is free or "floating" (e.g., flexible or movable), allowing for better load-bearing contact with one or more planetary gears. One problem with including such a flexible shaft in a turbine engine is the vibration and / or oscillation that can occur in the shaft due to the high-speed rotation of the engine system. For example, the flexible shaft often acts as a cantilever beam. Consequently, vibrations of the flexible shaft can cause wear and fretting of various components, including, for example, bushings designed to support the various components. The present disclosure therefore relates to a damper system disposed at the free end of a flexible shaft to limit shaft vibrations and / or oscillations during an operating cycle of a turbine engine. According to one embodiment, the damper system includes an oil system to ensure flexibility and / or conformability of the shaft in a sun gear configuration.

[0019] Referring now to the accompanying drawings, Figure 1 and Figure 2 Various views of a gas turbine engine 10 (herein referred to as “engine 10”) are shown according to an embodiment of the present disclosure. Figure 1 As shown, the engine 10 is shown as a high bypass turbofan engine incorporating an exemplary embodiment of a flexible coupling shaft 100 according to aspects of the present disclosure. Figure 2 In FIG, the engine 10 is shown as a turboprop engine incorporating an exemplary embodiment of a flexible coupling shaft 100 according to aspects of the present disclosure. Although further described below with reference to turbofan engines and / or turboprop engines, the present disclosure is also generally applicable to wind turbines and turbomachinery, including, for example, propfan gas turbine engines, turbojet gas turbine engines, and turboshaft gas turbine engines, including marine turbine engines and industrial turbine engines and auxiliary power units. Figure 1 As shown, the engine 10 has an axial centerline axis 12 extending therethrough for reference purposes. Figure 1 and Figure 2 As shown, the engine 10 further defines an axial direction A, a radial direction R, a front end 98 along the axial direction A, and a rear end 99 .

[0020] According to one embodiment, the engine 10 may include an engine core 20 and a fan / propeller assembly 14. The engine core 20 may generally include a compressor section 21, a combustion section 26, and a turbine section 31 in a serial flow arrangement. The compressor section 21 may define one or more compressors, such as a high pressure compressor (HPC) 24 and a low pressure compressor (LPC) 22. The turbine section 31 may define one or more turbines, such as a high pressure turbine (HPT) 28 and a low pressure turbine (LPT) 30. In various embodiments, the compressor section 21 may also include an intermediate pressure compressor (IPC). In other embodiments, the turbine section 31 may also include an intermediate pressure turbine (IPT). In wind turbine applications, the engine core 20 may generally define one or more generators.

[0021] The low-pressure compressor (LPC) 22 and high-pressure compressor (HPC) 24 in the compressor section 21, as well as the high-pressure turbine (HPT) 28 and low-pressure turbine (LPT) 30 in the turbine section 31, may each include one or more rotors 32. In one embodiment, the rotors 32 comprise one or more shafts 35 of the engine 10, connecting the compressor section 21 to the turbine section 31. In other embodiments, the rotors 32 generally define a disk 33 extending at least partially in a radial direction R and a plurality of airfoils 36 connected in a circumferentially adjacent arrangement and extending outwardly from the disk 33 in the radial direction R. In one embodiment, the one or more rotors 32 may each be connected together. For example, each rotor 32 of the turbine section 31 or the compressor section 21 may be connected by mechanical fasteners (e.g., bolts, nuts, screws, and / or rivets), or by a bonding process (e.g., welding, friction bonding, diffusion bonding, etc.). In various embodiments, the one or more compressors of the compressor section 21 may be drivingly connected to and rotatable with the one or more turbines of the turbine section 31 via the one or more shafts 35.

[0022] The fan / propeller assembly 14 generally includes a fan rotor / propeller shaft 15. The fan rotor / propeller shaft 15 includes a plurality of fan / propeller blades 42 coupled to and extending outwardly from the fan rotor / propeller shaft 15 in a radial direction R. Figure 1 and Figure 2 In the illustrated embodiment, the fan rotor / propeller shaft 15 may extend in an axial direction A from a reduction gearbox or power gearbox 45 (referred to herein as “gearbox 45 ”) toward a forward end 98 . The fan / propeller assembly 14 also includes a flexible coupling shaft 100 coupled to the gearbox 45 and extending toward an aft end 99 and coupled to the engine core 20 .

[0023] In one embodiment, the gearbox 45 may include an epicyclic gear train 50 including a sun gear 52 and a plurality of planet gears 54. The sun gear 52 is axially mounted to the flexible coupling shaft 100 and concentric with the flexible coupling shaft 100, such that the sun gear 52 is attached to or integral with the flexible coupling shaft 100. A plurality of planet gears 54 are mounted to the sun gear 52, wherein the plurality of planet gears 54 are supported by various bearings for rotation (e.g., rollers, balls, or other bearing types, such as journal bearings). The plurality of planet gears 54 may each be fixed so that each planet gear 54 rotates on a fixed axis relative to the sun gear 52. A ring gear 56 (or ring gear) engages with and surrounds the plurality of planet gears 54. The ring gear 56 is also connected to an output element to allow rotation and transmit power and torque from the sun gear 52 through the plurality of planet gears 54. According to one embodiment, the ring gear 56 may be coupled to, for example, a fan rotor or propeller shaft (see, e.g., FIG. 1 ). Figure 1 and Figure 2 The output element may be in the form of a fan rotor / propeller shaft 15 or otherwise integrated with the output element. In various embodiments, the gearbox 45 may further include additional planetary gears radially disposed between the plurality of planetary gears 54 and the sun gear 52 or between the plurality of planetary gears 54 and the ring gear 56.

[0024] like Figure 1 and Figure 2 As further shown, a flexible coupling shaft 100 is connected to the engine core 20 to transfer torque and power to the gearbox 45 to the fan rotor / propeller shaft 15 via the sun gear 52. The fan rotor / propeller shaft 15 can be connected to a surrounding ring gear 56 (or ring gear) or planetary gears 54 to receive torque from the sun gear 52 and transfer torque to drive the fan / propeller assembly 14. When power and torque are transferred from the engine core 20, the gearbox 45 provides power and torque to the fan rotor / propeller shaft 15 at an output speed that is more suitable for the fan / propeller assembly 14 to be regulated. For example, the gearbox 45 can reduce the speed of the fan rotor / propeller shaft 15 relative to the engine core 20 by two times or more. According to one embodiment, the gearbox 45 reduces the rotational speed from the engine core 20 (e.g., the compressor section 21 or the turbine section 31) and provides the desired amount of torque and rotational speed to the fan / propeller assembly 14.

[0025] During operation of the engine 10, as described with respect to Figure 1 and 2As shown and described herein, a quantity of air, schematically indicated by arrow 90, enters engine 10. As air 90 passes through fan / propeller blades 42, a portion of the air, schematically indicated by arrow 91, is directed or routed outside of engine core 20 to provide propulsion. Additionally, another portion of the air, schematically indicated by arrow 92, is directed or routed into compressor section 21 through associated inlet 80. Air 92 is progressively compressed as it passes through compressor section 21 (e.g., through LPC 22 and HPC 24) toward combustion section 26.

[0026] The now compressed air flows into the combustion section 26 as schematically indicated by arrows 93, where fuel is introduced, mixed with at least a portion of the compressed air 93, and ignited to form combustion gases 94. The combustion gases 94 flow into the turbine section 31, causing the rotating components of the turbine section 31 to rotate and support the operation of the respectively coupled rotating components in the compressor section 21 and / or the fan / propeller assembly 14. For example, the HPC 24 and the HPT 28 may be coupled and rotatable to drive the engine 10 and generate the combustion gases 94 in the combustion section 26 to drive the LPT 30. The LPT 30 may be connected to the LPC 22.

[0027] Figure 3 A gas turbine engine (see e.g. Figure 1 and 2 Engine 10) Figure 1 and Figure 2 An embodiment of the gearbox 45. Figure 3 The gearbox 45 includes a gearbox for transferring the engine core (see e.g. Figure 1 and 2 The engine core 20) is connected to the gearbox 45 and / or fan / propeller assembly (see e.g. Figure 1 and Figure 2 The flexible coupling shaft 100 of the fan / propeller assembly 14) is connected to the fan / propeller assembly 14. Figure 3 As shown, the flexible coupling shaft 100 is connected to the engine core, such as a power turbine, via a coupling member 210 that interfaces with the engine core. The gearbox 45 includes a housing 220 in which the epicyclic gear train 50 is housed. As described above, the epicyclic gear train 50 includes a sun gear and a plurality of planetary gears (see also, for example, FIG. Figure 6E ).

[0028] Figure 4 and Figure 5 According to one embodiment of the present disclosure, Figure 3 The gearbox 45 is shown connected to the system of the engine core 20 in the turbine engine or engine 10. Figure 4 and Figure 5As shown, the gearbox 45 includes a flexible coupling shaft 100 for coupling to the engine core 20 via a coupling member (see, e.g., Figure 3 The coupling member 210 ) connects the flexible coupling shaft 100 to the engine core 20 , such as a power turbine.

[0029] The sun gear 52 and the plurality of planetary gears 54 (or layshafts) are included as described above (see also e.g. Figure 6E ) is housed within the housing 220 of the gearbox 45. The sun gear 52 of the epicyclic gear train 50 interacts with the flexible coupling shaft 100, while the planetary gears 54 interact with the sun gear 52 (as further described below). The planetary gears 54 are also connected to one or more spur gears 325A, 325B on the first and second reduction stages. For example, according to one embodiment, the sun gear 52 and the first spur gear 325A on the planetary gears 54 comprise a first reduction stage gear, while the second spur gear 325B on the planetary gears 54 and the ring gear 56 comprise a second reduction stage gear, which allows the total reduction value of the gearbox 45 to be obtained. The second spur gear 325B is disposed within the ring gear 56 of the epicyclic gear train 50 (as further described below). As Figure 5 As further shown, the gearbox 45 also includes: (i) a first-stage straddled layshaft (e.g., first spur gear 325A on the planetary gear 54) and a second-stage outer layshaft (e.g., second spur gear 325B on the planetary gear 54), wherein the first-stage straddled layshaft has the first spur gear 325A between a pair of rollers 326A and 326B, which is part of the first reduction stage described above, and the second-stage outer layshaft has the second spur gear 325B outside the pair of rollers 326A and 326B, which is part of the second reduction stage described above; and (ii) a two-piece carrier 332A, 332B. In addition, the gearbox 45 includes an additional spur gear 340 connected to the ring gear 56, which can be used to transmit rotation to an external accessory component (not shown), such as a pitch control unit (PCU), via a dedicated axis and / or a gear shaft engaged with the additional spur gear 340.

[0030] Figures 6A to 6E Shown in more detail Figures 1 to 5 The various components of the epicyclic gear train 50 of the gearbox 45 are shown in the embodiment. In particular, Figure 6A The sun gear 52 of the epicyclic gear train 50 is shown. Figure 6A As shown, the epicyclic gear train 50 (see for example Figure 6E ) includes a set of gears 442 that are configured to engage with one or more planetary gears 54 (or layshafts).

[0031] Figure 6B Shown Figure 1-5One of the planetary gears 54 (or layshafts) of the epicyclic gear train 50 of the gearbox 45 shown in the embodiment of FIG. The planetary gear 54 includes a first set of gears 432 configured to engage with the set of gears 442 of the sun gear 52 (see, for example, FIG. Figure 6E ). The planetary gear 54 also includes a second spur gear 325B configured to engage with the ring gear 56 (see, for example Figure 6C ).

[0032] Figure 6C Shown Figure 1-5 The ring gear 56 of the epicyclic gear train 50 of the gearbox 45 is shown in the embodiment of FIG. Figure 6C As shown, the ring gear 56 includes a first set of gears 462 configured to engage with at least the second spur gear 325B of one or more planetary gears 54 (see, e.g., Figure 6E ). Gear ring 56 also includes an opening 464 through which fan rotor / propeller shaft 15 can extend to engage flexible coupling shaft 100 (see, e.g., Figure 6E ). The opening 464 of the ring gear 56 includes a second set of gears 465 that are configured to engage with a set of gears 484 of the fan rotor / propeller shaft 15 (see, e.g., Figure 6D ).

[0033] Figure 6D Shown Figure 1-5 In the embodiment shown, the fan rotor / propeller shaft 15 is connected to the epicyclic gear train 50 of the gearbox 45. Figure 6D As shown, the fan rotor / propeller shaft 15 includes a set of gears 484 that are configured to engage with the second set of gears 465 of the ring gear 56 (as described above). The fan rotor / propeller shaft 15 also includes a coupling member 482 for connecting the fan rotor / propeller shaft 15 to the fan / propeller assembly (see, e.g., FIG. Figure 1 and 2 Other components of the fan / propeller assembly 14).

[0034] Figure 6E Shown Figure 1-5 The complete epicyclic gear train 50 of the gearbox 45 is shown in the embodiment of FIG. Figure 6E As shown, the epicyclic gear train 50 includes: (i) a sun gear 52 engaged with a flexible coupling shaft 100 via a flexible connection and / or coupling; and (ii) a sun gear 52 engaged with a flexible coupling shaft 100 via a corresponding set of gears (see, e.g., Figure 6B The first set of gears 432 of the planetary gears 54 is configured to Figure 6AThe plurality of planetary gears 54, 54A, 54B (or layshafts) engaged with the sun gear 52 (the set of gears 442 of the sun gear 52) are engaged with the sun gear 52. Each of the planetary gears 54, 54A, 54B includes a second spur gear 325B configured to engage with the first set of gears 462 of the ring gear 56. Figure 6E Further shown is the fan rotor / propeller shaft 15, which extends into the ring gear 56 for interacting with the flexible coupling shaft 100. As described above, the fan rotor / propeller shaft 15 includes a coupling member 482 for connecting the fan rotor / propeller shaft 15 to the fan / propeller assembly (see, e.g., FIG. Figure 1 and 2 The flexible coupling shaft 100 further includes a coupling member 210 for connecting the flexible coupling shaft 100 of the gearbox 45 to the engine core 20 (see, for example, FIG. Figure 3 ).

[0035] like Figure 6E As further shown in the embodiment of FIG, during operation, the fan rotor / propeller shaft 15 is configured to rotate in a first direction A (e.g., clockwise), while the flexible coupling shaft 100 is configured to rotate in a second direction B (e.g., counterclockwise). According to one embodiment, the turbine of the engine core (see, e.g., FIG. Figure 1 and 2 The energy or power generated by the turbine section 31 of the engine core 20 of the engine is transferred to the flexible coupling shaft 100 via this rotation. However, according to one embodiment, due to the high-speed rotation of the engine system (e.g., the turbine of the engine core), the flexible coupling shaft 100 vibrates and / or oscillates because the flexible coupling shaft 100 generally acts as a cantilever beam due to the flexible connection and / or coupling of the flexible coupling shaft 100 with the sun gear 52 and / or the epicyclic gear train 50. As described above, these vibrations and / or oscillations of the flexible coupling shaft 100 cause wear and micro-motion events to various components of the system. Therefore, as discussed in more detail below, a damper system (see, e.g., FIG. 1 ) provided at the free end of the flexible coupling shaft 100 (i.e., the end of the flexible coupling shaft 100 that is engaged with the sun gear 52 of the epicyclic gear train 50 via a flexible connection and / or coupling) is provided. Figure 8A and 9A Damper systems 560 and 560') are provided to limit shaft vibrations and / or oscillations during the operating cycle of the turbine engine.

[0036] Figure 7 1 shows a cross-sectional view of an arrangement in a turbine engine for connecting a gearbox to an engine core via a shaft having a metering tube including a damper system 560 according to one embodiment of the present disclosure. Figure 7As shown, a portion of a turbine engine 500 includes a flexible coupling shaft 100 connecting the gearbox 45 and the engine core 20. The flexible coupling shaft 100 includes a metering tube 510 in the interior of the flexible coupling shaft 100. The metering tube 510 is connected to the gearbox 45 and the engine core 20 via a bushing (see, for example, FIG. Figure 8A The metering tube 510 defines, along an axial direction A, (i) a first end 511 proximate the aft end 599 of the turbine engine 500 and (ii) a second end 512 proximate the forward end 598 of the turbine engine 500, wherein the first end 511 is proximate the engine core 20 and the second end 512 is proximate the sun gear 52 and / or fan / propeller assembly 514 of the gearbox 45. The flexible coupling shaft 100 and / or metering tube 510 is (i) connected to the engine core 20 at the first end 511 via a fixed (or non-movable) connection and (ii) connected to the sun gear 52 of the gearbox 45 at the second end 512 via a flexible (or movable) connection or coupling (as described above). For example, as Figure 7 As shown in the embodiment of FIG. , the flexible coupling shaft 100 may include a coupling 518 extending at least partially in a radial direction R, coupled to the engine core 20. In one embodiment, the coupling 518 defines one or more fastening locations 524 at which one or more rotors 532 of the engine core 20 and the coupling 518 are attached in an axially adjacent arrangement. In another embodiment, the coupling 518 defines a plurality of apertures 522 through which one or more fasteners 523 may extend into the rotors 532 of the engine core 20. The plurality of apertures 522 may extend generally in the axial direction A through the coupling 518 and the rotors 532. In various embodiments, the one or more fasteners 523 and / or fastening locations 524 may include mechanical fasteners (e.g., but not limited to, bolts, nuts, screws, and / or rivets), and / or fastening or joining processes (e.g., welding or bonding processes, including but not limited to friction welding or diffusion bonding, or combinations thereof).

[0037] like Figure 7 As further shown in FIG. 5 , the rotor 532 may define an annular hub 534 extending from the disk 533 of the rotor 532 in the axial direction A. The annular hub 534 of the rotor 532 may generally extend in the axial direction A toward the gearbox 45. In one embodiment, the turbine engine 500 further includes one or more bearings 515A, 515B coupled to the hub 534 of the rotor 532. In one embodiment, as Figure 7As shown, one or more bearings 515A, 515B are coupled to the hub 534 of the rotor 532, from which the flexible coupling shaft 100 extends toward the gearbox 45. The one or more bearings 515A, 515B can be disposed between the first end 511 and the second end 512 of the flexible coupling shaft 100 and / or the metering tube 510. The bearings 515A, 515B can also be coupled to one or more static frames 562 that are configured to coaxially position the one or more rotors 532 along the axial direction A.

[0038] Figure 7 Further shown is a flexible coupling shaft 100 and / or metering tube 510 extending from the rotor 532 in an axial direction A to the sun gear 52 of the gearbox 45 and extending in a radial direction R inside the hub 534. The flexible coupling shaft 100 can define one or more platforms 505 extending at least partially in the radial direction R and adjacent to the inner diameter of the hub 534 of the rotor 532 defining the disk 533. The one or more platforms 505 can further extend at least partially in the axial direction A. The one or more platforms 505 can define a clearance fit between the platforms 505 and the hub 534 to at least partially retain the flexible coupling shaft 100 relative to the rotor 532. According to one embodiment of the present disclosure, disposed at the second end 512 of the flexible coupling shaft 100 and / or metering tube 510 is a damper system 560. Damper system 560 includes an oil drain system configured to limit vibrations and / or oscillations of metering tube 510 and / or its associated flexible coupling shaft 100 during an operating cycle of turbine engine 500. Damper system 560 (e.g., oil drain system) utilizes a volume of pressurized oil provided to damper system 560 through passage 570 and an oil space 575 created in an area above sun gear 52 and / or gearbox 45. The pressurized oil provided to damper system 560 allows for misalignment of metering tube 510 and / or its associated flexible coupling shaft 100 and reduces vibrations and / or oscillations during rotation of flexible coupling shaft 100.

[0039] Figure 8A and 8B An embodiment according to the present disclosure is shown Figure 7 An enlarged partial cross-sectional view of the damper system 560 is shown in FIG. Figure 8A and 8BAs shown, the damper system 560 disposed at the second end 512 (or free end) of the flexible coupling shaft 100 and / or metering tube 510 includes a ball bearing 600 (or roller bearing) comprising balls 610 (or rollers) positioned between an inner ring 615A (or inner race) and an outer ring 615B (or outer race). As described above, pressurized oil (P) is provided to the damper system 560 from the oil space 575 to the passage 570, which is generated in the area above the sun gear 52 and / or the flexible coupling shaft 100 or metering tube 510. The pressurized oil (P) travels to a circumferential oil pressure chamber 620 generated around the outer ring 615B of the ball bearing 600 and / or added to the top of the ball bearing 600. According to one embodiment, the thickness of the outer ring 615B of the ball bearing 600 allows for controlled oil leakage (L) into the ball bearing 600 and / or damper system 560. According to another embodiment, oil is further provided to the area around the second end 512 (or free end) of the metering tube 510 via an oil distribution passage or external oil injector 640. As described above, the damper system 560 (e.g., an oil drainage system) ensures that the metering tube 510 and / or its associated flexible coupling shaft 100 is not subjected to the sun gear configuration (see, e.g., FIG. Figure 6E ) while also reducing the flexibility from being in a sun gear configuration (see e.g. Figure 6E ) to the metering tube 510 and / or its associated flexible coupling shaft 100. According to one embodiment, the metering tube 510 receives vibrations from the flexible coupling shaft 100 through a bushing (e.g., a cobalt bushing 520) on which the metering tube 510 is supported by the flexible coupling shaft 100. Figure 8A As shown in the embodiment of FIG. 5 , the damper system 560 is positioned on the metering tube 510 and the damping effect (ie, reduction of vibration) can be returned to the flexible coupling shaft 100 through the bushing (eg, the cobalt bushing 520 ).

[0040] Figure 9A and 9B FIG. 5 shows an enlarged partial cross-sectional view of a damper system 560′ according to another embodiment of the present disclosure. Figure 9A and 9BAs shown, the damper system 560' provided at the second end 512 (or free end) of the flexible coupling shaft 100 and / or the metering tube 510 includes a journal bearing in the form of an oil distributor 700. As described above, pressurized oil (P) is provided to the damper system 560' from the oil space 575 to the channel 570, which is created in the area above the sun gear 52 and / or the flexible coupling shaft 100 or the metering tube 510. The pressurized oil (P) travels to the circumferential oil pressure chamber 720 (or channel) created in the area between the oil distributor 700 and the outer static support 705. According to one embodiment, the oil distributor 700 (or the journal bearing) is configured to retain the pressurized oil within the circumferential oil pressure chamber 720. As described above, the damper system 560' (e.g., an oil drainage system) ensures that the metering tube 510 and / or its associated flexible coupling shaft 100 are maintained in the sun gear configuration (see, e.g., FIG. 1 ). Figure 6E ) while also reducing the flexibility from being in a sun gear configuration (see e.g. Figure 6E )'s engine to the vibrations of the metering tube 510 and / or its associated flexible coupling shaft 100.

[0041] According to an embodiment of the present disclosure, Figure 10A and 10B Shown Figure 9A and 9B The oil distributor 700 of the damper system 560', Figure 10B Shown Figure 10A A partial cross-sectional view of the oil distributor 700 is shown in FIG. Figure 10A and 10B As shown, the oil distributor 700 includes an outer housing 715 and an inner bushing 710 configured to receive a flexible coupling shaft and / or a metering tube (e.g., metering tube 510). The oil distributor 700 also includes (i) one or more piston rings 750 and (ii) an inner oil distribution portion 760 (or spiral groove) having radial holes 712A, 712B configured to supply oil to the inner bushing 710, thereby supplying oil to the flexible coupling shaft and / or metering tube (e.g., metering tube 510). According to one embodiment, the one or more piston rings 750 are stationary components, and the oil distributor 700 is configured to rotate at the engine speed frequency. According to Figure 10A and 10B The embodiments of the present invention provide an alternative solution for distributing oil to the flexible coupling shaft and / or metering tube (e.g., metering tube 510), which is different from the external oil injector provided at the end of the flexible coupling shaft and / or metering tube (e.g., metering tube 510) (see e.g., Figure 8A According to an embodiment, the pressurized oil (P) is injected from the oil space (see for example Figure 9A The oil space 575) travels to the channel (see e.g. Figure 9A and 9B570) and thereafter travels to the circumferential oil pressure chamber or passage (see e.g. Figure 9A and 9B circumferential oil pressure chamber 720), thereby starting one or more piston rings 750.

[0042] Figure 11 A flow chart outlining the steps of an exemplary method of connecting a turbine engine gearbox and an engine core (referred to herein as "method 800") is shown. Method 800 can eliminate, minimize, and / or limit vibrations and / or oscillations that may occur in a flexible coupling shaft during an operating cycle of the engine. For purposes of illustration and discussion, Figure 11 The steps are depicted as being performed in a specific order. One of ordinary skill in the art, using the disclosure provided herein, will understand that the various steps of any method disclosed herein may be adjusted, modified, rearranged, omitted, or expanded in various ways without departing from the scope of the present disclosure.

[0043] Method 800 may utilize a turbine engine (e.g., Figure 1 、 2 , 4, 5, and 7 and described herein). Method 800 may include, at step 810, connecting a first end of a flexible coupling shaft to a rotor of a turbine engine, at step 820, extending the flexible coupling shaft in an axial direction to a gearbox of the turbine engine, and at step 830, connecting a second end of the flexible coupling shaft to the gearbox of the turbine engine. Method 800 may also include, at step 840, positioning a damper system proximate the second end of the flexible coupling shaft and / or metering tube. In one embodiment, as Figures 7 to 8B As shown, the damper system 560 may be in the form of a ball bearing 600. According to another embodiment, for example Figures 9A to 9B As shown, the damper system 560' may be in the form of an oil distributor 700 (or journal bearing). The method 800 may also include, at step 850, operating the engine and releasing pressurized oil to the damper system to minimize vibration and / or oscillation of the flexible coupling shaft and / or metering tube.

[0044] Figures 1 to 11 The systems and methods shown in and described herein can remove, minimize, and / or limit vibrations and / or oscillations that may occur in a flexible coupling shaft during an operating cycle of an engine. Furthermore, the systems and methods described herein provide a damper system that allows for misalignment and / or flexibility of the flexible coupling shaft while reducing vibrations and / or oscillations during rotation of the flexible coupling shaft.

[0045] about Figures 1 to 10BThe flexible coupling shaft (100) and other parts, components, or assemblies of the engine (10, 500) shown and described can be formed from metals suitable for use in turbine engines (including, but not limited to, iron-based, titanium-based, nickel-based, or cobalt-based alloys, each of which can include chromium, cobalt, tungsten, tantalum, molybdenum, and / or rhenium). The flexible coupling shaft (100) can be formed using casting, forging, machining, or a combination thereof. Additionally or alternatively, the flexible coupling shaft (100) can be formed as a single, unitary structure, or as an assembly of multiple components joined by one or more mechanical fasteners or joining processes, or a combination thereof.

[0046] Thus, in accordance with the principles of the present disclosure, a damper system and / or oil drain system is provided to limit vibrations in a flexibly coupled shaft or engine shaft having lubrication requirements.

[0047] According to the principles of the present disclosure, the oil pressure provided by the damper system limits the oscillation of the flexible coupling shaft or the engine shaft during high-speed rotation, and further limits the vibration on at least one bushing surface used to support the rotation of the flexible coupling shaft or the engine shaft, thereby avoiding micro-motion problems.

[0048] In accordance with the principles of the present disclosure, a damper system and / or dumping system is designed with a dedicated pressurized oil volume at the end of the flexible coupling shaft or engine shaft.

[0049] According to one embodiment of the present disclosure, in order to allow rotation of the flexible coupling shaft or the engine shaft, different arrangements may be proposed for the damper system, including, for example, a journal bearing (or oil distributor) and / or a single ball bearing.

[0050] According to one embodiment of the present disclosure, the active dumping action of oil via the damper system to the flexible coupling shaft may be proportional to the oil pressure and oil volume.

[0051] According to the principles of the present disclosure, a high-speed shaft can be supported with a suspension damper system that limits (i) high-frequency vibrations of the high-speed shaft and / or (ii) micro-motion problems on the shaft components used to support the shaft, while increasing the life limit of the shaft and / or shaft components.

[0052] According to the principles of the present disclosure, a damper system is provided that allows for the use of various types of bushing materials, including downgrading the type of bushing material to meet less wear-appropriate requirements, which saves assembly costs and material costs.

[0053] Further aspects of the disclosure are provided by the subject matter of the following clauses.

[0054] An engine assembly defining an axial direction, the engine assembly comprising: a gearbox; an engine core comprising at least one rotor; a flexible coupling shaft having a first end and a second end along the axial direction, wherein the first end of the flexible coupling shaft is connected to the engine core and the second end of the flexible coupling shaft is connected to the gearbox; and a damper system positioned at the second end of the flexible coupling shaft, wherein the damper system is configured to reduce vibrations of the flexible coupling shaft during operation of the engine assembly.

[0055] The engine assembly of any preceding clause, further comprising an external oil injector configured to provide oil to an area surrounding the second end of the flexible coupling shaft.

[0056] An engine assembly according to any preceding clause, further comprising a passage and an oil space configured to distribute pressurized oil to the damper system.

[0057] An engine assembly according to any preceding clause, further comprising a circumferential oil pressure chamber connected to the passage and configured to receive the pressurized oil.

[0058] An engine assembly as claimed in any preceding clause, wherein the damper system comprises a ball bearing configured to provide the pressurised oil to the flexible coupling shaft.

[0059] An engine assembly according to any preceding clause, wherein the ball bearing comprises balls positioned between an outer ring and an inner ring such that the circumferential oil pressure chamber is created around the outer ring of the ball bearing.

[0060] An engine assembly as recited in any preceding clause, wherein the damper system includes a journal bearing defining an oil distributor configured to provide the pressurized oil to the flexible coupling shaft.

[0061] An engine assembly as claimed in any preceding clause, wherein the oil distributor comprises an outer housing and an inner bushing configured to receive the flexible coupling shaft.

[0062] An engine assembly according to any preceding clause, wherein the oil distributor further comprises an inner oil distribution portion having radial bores configured to supply the pressurized oil to the inner liner.

[0063] An engine assembly according to any preceding clause, further comprising an epicyclic gear train disposed within the gearbox, the epicyclic gear train being configured to connect the flexible coupling shaft to the gearbox.

[0064] The engine assembly of any preceding clause, further comprising a propeller assembly having a propeller shaft configured to engage with the epicyclic gear train, wherein energy generated by the engine core is transferred to the propeller shaft.

[0065] An engine assembly as described in any preceding clause, wherein the epicyclic gear train includes a sun gear and one or more planet gears configured to engage with the sun gear.

[0066] An engine assembly according to any preceding clause, wherein each of the one or more planetary gears comprises a spur gear, and wherein the epicyclic gear train further comprises a ring gear configured to engage with each of the spur gears of each of the one or more planetary gears.

[0067] An engine assembly as claimed in any preceding clause, wherein the flexible coupling shaft is configured to engage with the sun gear of the epicyclic gear train.

[0068] An engine assembly as claimed in any preceding clause, wherein the flexible coupling shaft is coupled to the sun gear of the epicyclic gear train via a flexible connection.

[0069] An engine assembly as claimed in any preceding clause, wherein the flexible coupling shaft is connected to the engine core via a fixed connection.

[0070] A method of arranging an engine assembly, the engine assembly defining an axial direction and comprising (i) an engine core having at least one rotor and (ii) a gearbox, the method comprising connecting a first end of a flexible coupling shaft to the at least one rotor of the engine core, extending the flexible coupling shaft in the axial direction to the gearbox, connecting a second end of the flexible coupling shaft to the gearbox, and positioning a damper system proximate the second end of the flexible coupling shaft, wherein the damper system is configured to reduce vibrations of the flexible coupling shaft during operation of the engine assembly.

[0071] The method of any preceding clause, further comprising operating the engine assembly and releasing pressurized oil to the damper system to reduce the vibration of the flexure coupling shaft during the operation of the engine assembly.

[0072] A method as in any preceding clause, wherein the damper system comprises at least one of a ball bearing or a roller bearing configured to provide the pressurized oil to the flexible coupling shaft.

[0073] A method as in any preceding clause, wherein the damper system comprises a journal bearing defining an oil distributor, the oil distributor being configured to provide the pressurized oil to the flexible coupling shaft.

[0074] A method according to any preceding clause, wherein the gearbox comprises an epicyclic gear train configured to connect the flexible coupling shaft to the gearbox.

[0075] The method of any preceding clause, wherein the engine assembly further comprises a propeller assembly having a propeller shaft configured to engage with the epicyclic gear train, wherein the engine core generates energy that is transferred to the propeller shaft.

[0076] A method as in any preceding clause, wherein the epicyclic gear train comprises a sun gear and one or more planet gears configured to engage with the sun gear.

[0077] A method according to any preceding clause, wherein the second end of the flexible coupling shaft is connected to the sun gear of the epicyclic gear train of the gearbox via a flexible connection.

[0078] A method as in any preceding clause, wherein the first end of the flexible coupling shaft is connected to the at least one rotor of the engine core via a fixed connection.

[0079] Although the foregoing description is directed to preferred embodiments, it should be noted that other changes and modifications will be apparent to those skilled in the art and may be made without departing from the spirit or scope of the present disclosure. In addition, features described in conjunction with one embodiment may be used in conjunction with other embodiments, even if not explicitly stated above.

Claims

1. An engine assembly (10) defining an axial direction (A), characterized in that The engine assembly (10) comprises: Gearbox (45); An engine core (20), the engine core (20) comprising at least one rotor; a flexible coupling shaft (100), the flexible coupling shaft (100) having a first end (511) and a second end (512) along the axial direction (A), wherein the first end (511) of the flexible coupling shaft (100) is connected to the engine core (20), and the second end (512) of the flexible coupling shaft (100) is connected to the gearbox (45); a damper system (560, 560') positioned at the second end (512) of the flexible coupling shaft (100), wherein the damper system (560, 560') is configured to reduce vibrations of the flexible coupling shaft (100) during operation of the engine assembly (10); and (i) a channel (570) and an oil space (575) configured to distribute pressurized oil (P) to the damper system (560, 560'), and (ii) a circumferential oil-filled oil pressure chamber (620, 720) connected to the channel (570) and configured to receive the pressurized oil (P), wherein the circumferential oil-filled oil pressure chamber (620, 720) is created in a region between an oil distributor (700) and an outer static support (705), and the oil distributor (700) is configured to retain the pressurized oil (P) within the circumferential oil-filled oil pressure chamber (620, 720).

2. The engine assembly according to claim 1, wherein: Further included is an external oil injector (640) configured to provide oil to an area surrounding the second end (512) of the flexible coupling shaft (100).

3. The engine assembly according to claim 1, wherein: The damper system (560) includes a ball bearing (600) configured to provide the pressurized oil (P) to the flexible coupling shaft (100).

4. The engine assembly according to claim 3, characterized in that The ball bearing (600) includes balls (610) positioned between an outer ring (615B) and an inner ring (615A), such that a circumferential oil-filled oil pressure chamber (620) is created around the outer ring (615B) of the ball bearing (600).

5. The engine assembly according to claim 1, wherein: The damper system (560') includes a journal bearing, the journal bearing defining an oil distributor (700), the oil distributor (700) being configured to provide the pressurized oil (P) to the flexible coupling shaft (100).

6. The engine assembly according to claim 5, characterized in that The oil distributor (700) includes an outer housing (715) and an inner bushing (710) configured to receive the flexible coupling shaft (100).

7. The engine assembly according to claim 6, characterized in that The oil distributor (700) further comprises an inner oil distribution portion (760) having radial holes (712A, 712B), wherein the radial holes (712A, 712B) are configured to supply the pressurized oil (P) to the inner bushing (710).

8. The engine assembly according to claim 1, wherein: The invention further comprises an epicyclic gear train (50) disposed within the gear box (45), the epicyclic gear train (50) being configured to connect the flexible coupling shaft (100) to the gear box (45).

9. The engine assembly according to claim 8, wherein: Further included is a propeller assembly (14) having a propeller shaft (15) configured to engage with the epicyclic gear train (50), wherein energy generated by the engine core (20) is transferred to the propeller shaft (15).

10. The engine assembly according to claim 8, wherein: The epicyclic gear train (50) includes a sun gear (52) and one or more planet gears (54) configured to engage with the sun gear (52).

11. The engine assembly according to claim 10, wherein: wherein each of the one or more planetary gears (54) includes a spur gear (325A, 325B), and wherein the epicyclic gear train (50) further includes a ring gear (56) configured to engage with each of the spur gears (325A, 325B) of each of the one or more planetary gears (54).

12. The engine assembly according to claim 10, wherein: The flexible coupling shaft (100) is configured to engage with the sun gear (52) of the epicyclic gear train (50).

13. The engine assembly according to claim 10, wherein: wherein the flexible coupling shaft (100) is coupled to the sun gear (52) of the epicyclic gear train (50) via a flexible connection.

14. The engine assembly according to claim 1, wherein: The flexible coupling shaft (100) is connected to the engine core (20) via a fixed connection.

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