A repairable load-bearing structure for aircraft engines

Abstract

This invention relates to a repairable, fusible bearing structure for aero-engines, belonging to the technical field of engine bearing structures, and solves the problem of existing bearing structures affecting engine performance after being subjected to high-energy impacts. The repairable, fusible bearing structure of this invention includes: a fusible actuating element, an actuating element mounting ring, a limiting ring, and a squirrel cage structure; the limiting ring is sleeved on the outside of the squirrel cage structure; the actuating element mounting ring is disposed on the side of the limiting ring; the fusible actuating element is disposed between the squirrel cage structure and the actuating element mounting ring, and multiple fusible actuating elements are evenly spaced on the inner side of the actuating element mounting ring; the fusible actuating element can undergo plastic deformation under high-energy impact loads and can recover its initial shape after heating. The repairable, fusible engine rotor bearing structure of this invention can rapidly fuse and fail upon the instant of fan blade loss, ensuring safe deceleration of the engine rotor and enabling heat repair, thereby improving the operational stability of the engine rotor.

Description

Technical Field

[0001] This invention relates to the field of bearing structure technology for aero engines, and in particular to a repairable bearing structure for aero engines that can withstand melt-through. Background Technology

[0002] For high-bypass turbofan engines, large fan blades are prone to breakage and ejection when struck by foreign objects such as birds or hail, creating high-energy impact loads on the rotor system and seriously threatening engine safety. To mitigate the damage caused by lost fan blades, a traditional solution is to introduce a fusible load-bearing structure design into the engine's low-pressure rotor system. This design creates a weak point at the front support of the low-pressure rotor, causing partial or complete failure of the front support under high-energy impact loads. This alters the load transmission path, reducing the transmission of high-energy loads to critical components; it also reduces the rotor's load-bearing stiffness and critical speed, thereby reducing the resonance response when the rotor decelerates past the critical speed, ensuring engine safety.

[0003] There are two main types of common fusing designs. One is the partial fusing structure disclosed in patent "US 5974782," which achieves partial fusing failure by setting a double-layer conical shell and easy-cut bolts at the front support of the low-pressure rotor. The other is the complete fusing structure disclosed in patent "US 6447248," which achieves complete fusing failure by setting a thinning section at the conical shell at the front support of the low-pressure rotor. Traditional fusing structures of this type can effectively reduce load and vibration during the rotor deceleration process after the loss of fan blades. However, since this type of structure cannot be recovered after failure, it will greatly increase the steady-state amplitude of the rotor and the support reaction force at the remaining support during the wind turbine operation, affecting the rotor's operational stability and safety.

[0004] For the reasons mentioned above, the present invention provides a load-bearing structure that can melt and break under high-energy load impact and can be repaired after melting. Summary of the Invention

[0005] Based on the above analysis, the present invention aims to provide a repairable load-bearing structure for aircraft engines to solve the problem that the existing fuse structure of aircraft engines cannot be restored after use, thus affecting the safety performance of the engine.

[0006] The objective of this invention is mainly achieved through the following technical solutions:

[0007] A fusible repairable load-bearing structure for an aero-engine, used to support the engine rotor, comprises: a fusible actuating element, an actuating element mounting ring, a limiting ring, and a squirrel cage structure; the limiting ring is an annular disc structure coaxial with the squirrel cage structure, and the actuating element mounting ring is a cylindrical structure coaxial with the squirrel cage structure, both located outside the squirrel cage structure; the actuating element mounting ring is disposed on the side of the limiting ring; the fusible actuating element is disposed between the squirrel cage structure and the actuating element mounting ring, and multiple fusible actuating elements are evenly spaced on the inner ring surface of the actuating element mounting ring; the fusible actuating element is capable of plastic deformation under high-energy impact loads and can recover its initial shape after heating.

[0008] Furthermore, the fusion actuating element is made of shape memory alloy.

[0009] Furthermore, it also includes: an outer retaining ring; the outer retaining ring is sleeved on the outside of the squirrel cage structure and can axially limit multiple fusible actuating elements.

[0010] Furthermore, the limiting ring includes: an outer limiting ring and an inner limiting ring; the outer limiting ring has a limiting ring mounting hole for mounting the limiting ring on the housing; the inner ring surface of the inner limiting ring has a gap with the outer ring surface of the cage structure.

[0011] Furthermore, the inner arc surface of the actuating element mounting ring is circumferentially spaced with multiple actuating element mounting slots and actuating element positioning bosses; the upper end of the fusible actuating element is engaged in the actuating element mounting slots, and the actuating element positioning bosses are used to circumferentially limit the fusible actuating element.

[0012] Furthermore, it also includes a heating module, which is used to heat the fusion actuating element after plastic deformation.

[0013] Furthermore, the heating module comprises a heating element and a wire; the heating element generates heat when energized.

[0014] Furthermore, the heating module includes: an air intake shroud; the air intake shroud covers the exterior of multiple fusible actuating elements; the air intake shroud is used to introduce hot air to heat the fusible actuating elements.

[0015] Furthermore, a through hole is provided on the inner ring of the limiting ring.

[0016] A load-bearing method for a fusible and repairable load-bearing structure in an aero-engine, characterized by comprising the following steps:

[0017] Step S1: When the engine is running normally, the deformation of the fusible actuating element is within the linear elastic range;

[0018] Step S2: At the moment the fan blade is lost, the fusible actuating element undergoes plastic deformation under the impact of the high-energy unbalanced load, and the radial load is transmitted outward from the squirrel cage structure. The fusible actuating element is in the load-bearing fusible state.

[0019] Step S3: After the fusible actuation element is fused, the critical speed of the engine rotor decreases;

[0020] Step S4: After the engine rotor speed is reduced to the windmill speed, the fusible actuating element is heated to restore the plastic deformation of the fusible actuating element.

[0021] The technical solution of this invention can achieve at least one of the following effects:

[0022] 1. This invention provides a repairable fusible bearing structure for aero-engines. To overcome the shortcomings of traditional fusible bearing structures, which cannot be restored after fusible failure and affect the operational stability of the engine during the windmill stage, the repairable fusible bearing structure of this invention arranges multiple fusible actuating elements circumferentially on the outer side of the squirrel cage structure. This allows it to absorb high-energy impact loads at the moment the fan blades are lost, passively reducing the load-bearing stiffness and ensuring safe deceleration of the rotor with a large imbalance. At the same time, the fusible actuating elements are made of shape memory alloy. By heating the fusible actuating elements to a specific temperature, structural repair can be performed during the windmill stage, restoring their initial structural shape and load-bearing effect, thereby improving the operational stability and safety of the rotor during the windmill stage.

[0023] 2. This invention provides a repairable fusible bearing structure for aircraft engines, which heats the fusible actuating element by means of an electric heating element or by introducing hot air, so that it can be restored to its initial shape, thereby achieving the effect of rapid repair of the fusible actuating element after it has melted.

[0024] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained from what is particularly pointed out in the description and drawings. Attached Figure Description

[0025] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0026] Figure 1 This is a three-quarter sectional view of a fusible repairable load-bearing structure for an aero-engine according to Embodiment 1 of the present invention;

[0027] Figure 2 This is a schematic diagram of the assembly of a fusible repairable load-bearing structure for an aero-engine in the casing according to Embodiment 1 of the present invention.

[0028] Figure 3 This is a three-dimensional structural schematic diagram of the fuse actuation element of Embodiment 1 of the present invention;

[0029] Figure 4 This is a front view of the fuse actuation element of Embodiment 1 of the present invention;

[0030] Figure 5 This is a three-dimensional structural schematic diagram of the actuating element mounting ring of the present invention;

[0031] Figure 6 This is a three-dimensional structural schematic diagram of the limiting ring of the present invention;

[0032] Figure 7 This is a three-dimensional structural diagram of the rat cage structure of the present invention;

[0033] Figure 8 This is a schematic diagram of the heating element for heating the fuse actuating element according to Embodiment 1 of the present invention;

[0034] Figure 9 This is a three-dimensional structural schematic diagram of the fuse actuation element in Embodiment 2 of the present invention;

[0035] Figure 10 This is a cross-sectional view of the fuse actuation element in Embodiment 2 of the present invention;

[0036] Figure 11 This is a side view of the fuse actuating element of Embodiment 2 of the present invention;

[0037] Figure 12 This is a schematic diagram of the structural composition of the heating module in Embodiment 2 of the present invention.

[0038] Figure label:

[0039] 1-Fuse actuating element; 2-Actuating element mounting ring; 3-Limiting ring; 4-Squirrel cage structure; 5-Outer retaining ring; 6-Jar; 7-Shaft; 8-Bearing; 9-Locking nut; 10-Inner retaining ring; 11-Air intake shroud; 12-Squirrel cage mounting screw; 13-Air intake shroud mounting screw; 14-Heating element;

[0040] 101 - Outer ring of the actuating element; 102 - Side plate of the actuating element; 103 - Inner ring of the actuating element;

[0041] 111 - First fuse hole; 112 - Second fuse hole;

[0042] 21-Actuator mounting slot; 22-Actuator positioning boss;

[0043] 31-Outer ring of the limiting ring; 311-Mounting hole of the limiting ring; 32-Inner ring of the limiting ring; 321-Through hole;

[0044] 41-Rat cage mounting ring; 42-Outer cage bar; 43-Inner cage bar; 44-Bearing ring; 411-Rat cage mounting hole; 441-Actuating element bearing ring surface; 442-Outer groove; 443-Bearing bearing ring surface; 444-Inner groove. Detailed Implementation

[0045] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0046] Example 1

[0047] One specific embodiment of the present invention discloses a fusible repairable load-bearing structure for an aero-engine, used to support the engine rotor, such as... Figure 1 , Figure 2 As shown, the repairable fusible bearing structure includes: a fusible actuating element 1, an actuating element mounting ring 2, a limiting ring 3, and a cage structure 4; the limiting ring 3 is an annular disc-shaped structure sleeved on the outside of the cage structure 4; the actuating element mounting ring 2 is a cylindrical structure coaxial with the cage structure 4, and the actuating element mounting ring 2 is disposed on the side of the limiting ring 3; the fusible actuating element 1 is disposed between the cage structure 4 and the actuating element mounting ring 2, and multiple fusible actuating elements 1 are installed at equal intervals on the inner side of the actuating element mounting ring 2; the fusible actuating element 1 can undergo plastic deformation under high-energy impact loads and can recover its initial shape after heating.

[0048] like Figure 1 As shown, the actuator mounting ring 2 provides radial and circumferential constraints on a single fusible actuator 1. Multiple fusible actuators 1 are mounted circumferentially at equal intervals on the actuator mounting ring 2 to form a ring-shaped actuation structure.

[0049] like Figure 2 As shown, the inner ring surface of the limiting ring 3 does not contact the outer ring surface of the squirrel cage structure 4, and a gap is left between them. The limiting ring 3 is used to limit the maximum radial amplitude of the fusible actuator 1 and the squirrel cage structure 4. That is, when the fusible actuator 1 and the squirrel cage structure 4 produce maximum deformation, the limiting ring 3 is in direct contact with the squirrel cage structure 4, and the radial load is transmitted through the limiting ring 3 to avoid irreparable catastrophic damage to the structure under extreme loads.

[0050] In this embodiment, the reversible squirrel cage structure 4 and the annular actuation structure are connected in parallel to provide load-bearing effect for the engine rotor, and the outer retaining ring 5 is used to axially position and constrain the fused actuating element 1.

[0051] In this embodiment, the fusion actuation element 1 is made of shape memory alloy; the fusion actuation element 1 is the core component of the repairable load-bearing structure, possessing multiple functions such as load bearing, fusing, and repair. Specifically, the fusion actuation element 1 is wire-cut from a shape memory alloy plate. The fusion actuation element 1 can remember its initial shape (shape memory effect), and when repairing the shape of the fusion actuation element 1 after fusing (undergoing plastic deformation), it only needs to be heated to a specific temperature.

[0052] like Figure 3 , Figure 4 As shown, in this embodiment, the fusible actuating element 1 is a π-shaped structural component.

[0053] In one specific embodiment of the present invention, such as Figure 3 , Figure 4 As shown, the fusible actuation element 1 includes: an outer ring 101, a side plate 102, and an inner ring 103. Both the outer ring 101 and the inner ring 103 are arc-shaped plate structures. The side plate 102 connects the outer ring 101 and the inner ring 103, and two side plates 102 are provided in a mirror-symmetrical configuration. The side plate 102 is a thin plate structure with a reverse-curved bow shape.

[0054] Furthermore, the outer ring 101 of the actuating element is engaged in the actuating element mounting groove 21 inside the actuating element mounting ring 2 by an interference fit. In this embodiment, the radial and circumferential fixation of the fusible actuating element 1 is achieved by the engagement of the outer ring 101 of the actuating element and the actuating element mounting ring 2. That is, the actuating element mounting groove 21 restricts the radial displacement and circumferential rotation of the fusible actuating element 1 relative to the actuating element mounting ring 2.

[0055] Furthermore, in the non-fuse state, the inner ring 103 of the actuating element is in contact with the outer ring surface of the squirrel cage structure 4; the squirrel cage structure 4 can transfer part of the radial load on the bearing 8 to the fuse actuating element 1, and provide elastic support through the fuse actuating element 1, which can buffer the small-amplitude vibration of the engine rotor in the inner ring of the bearing 8.

[0056] Furthermore, the connection points between the actuation element side plate 102 of the fusible actuation element 1 and the inner sides of the actuation element outer ring 101 and actuation element inner ring 103 are all provided with rounded corners. The radial thickness of the actuation element outer ring 101 is greater than the radial thickness of the actuation element inner ring 103; the central angle corresponding to the actuation element outer ring 101 is less than or equal to (not greater than) the central angle corresponding to the actuation element inner ring 103.

[0057] In this embodiment, by adjusting the thickness and / or axial length of the actuating element side plate 102, the load-bearing stiffness of the fusible actuating element 1 can be adjusted to meet different design requirements.

[0058] The working principle of the fusible actuation element 1 of the present invention is as follows: Under normal, relatively small loads, the deformation of the actuation element side plate 102 is within the linear elastic range, which can provide stable load-bearing stiffness; when the load is too large, the actuation element side plate 102 will undergo plastic deformation, causing its load-bearing stiffness to decrease in a sloping manner. In other words, the fusible actuation element 1 is the core component of the fusible repairable load-bearing structure. It can undergo plastic deformation under the high-energy impact load caused by blade loss, reducing the load-bearing stiffness of the load-bearing structure. At the same time, it can be restored by heating to recover its plastic deformation, thereby restoring the initial load-bearing stiffness.

[0059] Furthermore, such as Figure 2 As shown, the outer ring 101 of the fusible actuating element 1 is engaged in the actuating element mounting groove 21 of the actuating element mounting ring 2; the inner ring 103 of the fusible actuating element 1 is pressed against the outer ring surface of the squirrel cage structure 4. The outer retaining ring 5 is sleeved on the outside of the squirrel cage structure 4 and can axially limit the multiple fusible actuating elements 1.

[0060] In one specific embodiment of the present invention, such as Figure 5 As shown, the actuator mounting ring 2 is a cylindrical structure with multiple actuator mounting slots 21 and actuator positioning bosses 22 on its inner ring surface. The actuator mounting slots 21 and actuator positioning bosses 22 are spaced apart. That is, the multiple actuator mounting slots 21 are equally spaced on the inner ring surface of the actuator mounting ring 2, and the protruding part between two adjacent actuator mounting slots 21 is the actuator positioning boss 22.

[0061] Furthermore, the shape and dimensions of the actuating element mounting groove 21 are consistent with those of the actuating element outer ring 101, and the two can be installed in an interference fit to form a ring-shaped actuating structure. That is, the actuating element outer ring 101 of the fusible actuating element 1 is engaged in the actuating element mounting groove 21, the actuating element mounting groove 21 can radially limit the fusible actuating element 1, and the actuating element positioning boss 22 can circumferentially limit the fusible actuating element 1.

[0062] In this embodiment, as Figure 2 , Figure 7 As shown, the mouse cage structure 4 is a double-layer folding structure.

[0063] In one specific embodiment of the present invention, such as Figure 2 , Figure 7 As shown, the mouse cage structure 4 includes: a mouse cage mounting ring 41, outer cage bars 42, inner cage bars 43, and a support ring 44. The mouse cage mounting ring 41 has multiple mouse cage mounting holes 411 evenly distributed circumferentially for fixing the mouse cage structure 4 to the limiting ring 3. Multiple outer cage bars 42 and inner cage bars 43 are provided, and these multiple outer cage bars 42 and inner cage bars 43 together form a nested double-layer cage structure; one end of each outer cage bar 42 and inner cage bar 43 is connected to the mouse cage mounting ring 41, and the other end is fixedly connected to the support ring 44.

[0064] Specifically, the outer cage bars 42 and inner cage bars 43 are milled from double-layered cylindrical walls to provide elastic load-bearing stiffness. The load-bearing stiffness of the rat cage structure 4 can be adjusted by adjusting the number, length, thickness, or width of the outer cage bars 42 and / or inner cage bars 43.

[0065] Furthermore, the outer side of the bearing ring 44 is provided with an actuating element bearing ring surface 441 and an outer groove 442; the actuating element bearing ring surface 441 makes radial extrusion contact with the inner ring 103 of the fused actuating element 1, which can transmit part of the radial load to the fused actuating element 1; the outer retaining ring 5 is installed in the outer groove 442, and the outer retaining ring 5 contacts the sides of multiple fused actuating elements 1, which is used to axially constrain the annular actuating structure. In this embodiment, the outer retaining ring 5 can be a conventional C-shaped shaft elastic retaining ring, which is installed in the outer groove 442 of the squirrel cage structure 4 to restrict the axial displacement of the fused actuating element 1.

[0066] Furthermore, the bearing ring 44 is provided with a bearing bearing ring surface 443 and an inner groove 444 on its inner side; the bearing bearing ring surface 443 is in radial extrusion contact with the outer ring of the bearing 8, which can transmit the radial load on the bearing 8; an inner retaining ring 10 is installed in the inner groove 444, which is used to achieve axial constraint on the bearing 8.

[0067] In this embodiment, the actuating element mounting ring 2 and multiple circumferentially evenly distributed fusible actuating elements 1 form an annular actuating structure. The squirrel cage structure 4 is connected in parallel with the annular actuating structure to jointly provide load-bearing function for the engine rotor.

[0068] like Figure 6 As shown, the limiting ring 3 includes: an outer limiting ring 31 and an inner limiting ring 32; the outer limiting ring 31 has a limiting ring mounting hole 311 for mounting the limiting ring 3 on the housing 6; the inner ring surface of the inner limiting ring 32 has a certain radial gap with the outer ring surface of the cage structure 4.

[0069] In this embodiment, the limiting ring 3 is used to limit the radial amplitude of the front support point of the low-pressure engine rotor. When the radial amplitude of the support point is too large, the inner ring 32 of the limiting ring makes radial compression contact with the bearing ring 44 of the squirrel cage structure 4, and the load of the support point is directly transmitted outward through the limiting ring 3, avoiding irreversible damage to the fusible actuator 1 and the squirrel cage structure 4.

[0070] Specifically, the outer ring 31 of the limiting ring has multiple limiting ring mounting holes 311 evenly distributed circumferentially, used to fix the limiting ring 3 to the housing 6 and the cage mounting ring 41 of the cage structure 4. Simultaneously, the outer ring 31 of the limiting ring makes axial compression contact with the sides of the fusible actuating element 1 and the actuating element mounting ring 2, enabling axial positioning of the annular actuating structure composed of multiple fusible actuating elements 1. Specifically, cage mounting screws 12 are installed in the limiting ring mounting holes 311, and the cage mounting ring 41, the limiting ring 3, and the housing 6 are fixedly connected as a whole by the cage mounting screws 12.

[0071] Specifically, the inner ring 32 of the limiting ring has a plurality of through holes 321 evenly distributed in the circumferential direction. The through holes are used to assist in the repair of the fuse actuating element 1.

[0072] When hot air is used to heat the fuse actuating element 1, the through hole 321 can be used as an exhaust hole to discharge the hot air; when the heating element 14 is used to heat the fuse actuating element 1, the through hole 321 can be used as a lead hole to allow the lead wire connected to the heating element 14 to be led out.

[0073] In this embodiment, during the assembly of the repairable fusible load-bearing structure:

[0074] First, multiple fusible actuating elements 1 are respectively installed in multiple actuating element mounting slots 21 of the actuating element mounting ring 2 to form a ring actuating structure; then, the ring actuating structure and the limiting ring 3 are sequentially fitted onto the outside of the squirrel cage structure 4, and then the whole assembly is installed into the mounting hole of the housing 6, and the limiting ring 3 and the squirrel cage structure 4 are fixedly connected to the housing 6 by the squirrel cage mounting screws 12; at the same time, an outer retaining ring 5 is installed in the outer retaining slot 442 to axially fix the fusible actuating element 1 onto the squirrel cage structure 4; then, the bearing 8 is installed on the rotating shaft 7 (engine rotor), and the bearing 8 is limited on one side by the shoulder of the rotating shaft 7, and a locking nut 9 is fitted on the other side of the rotating shaft 7 to axially fix the bearing 8 onto the rotating shaft 7; finally, the rotating shaft 7 and the bearing 8 are installed into the squirrel cage structure 4, and the outer ring of the bearing is axially fixed by the inner retaining ring 10. Figure 2 As shown, after assembly, the bearing 8 coincides with the center plane of the annular actuating structure along the axial direction, thereby ensuring that the radial load is transmitted outward evenly.

[0075] Furthermore, in order to realize the automatic repair function of the fused actuating element, in this embodiment, the fused repairable bearing structure further includes a heating module, which is used to heat the fused actuating element 1 after plastic deformation.

[0076] In one specific embodiment of the present invention, such as Figure 8 As shown, the heating module consists of a heating element 14 and a wire; the heating element 14 generates heat when energized.

[0077] In another specific embodiment of the present invention, such as Figure 2 As shown, the heating module includes: an air intake shroud 11; the air intake shroud 11 covers the outside of a plurality of fusible actuating elements 1, and the air intake shroud 11 is used to introduce hot air to heat the fusible actuating elements 1.

[0078] In this embodiment, as Figure 2 As shown, when the fusible actuator 1 is heated by hot air, the air intake shroud 11 is mounted on the casing 6 by the air intake shroud mounting screws 13, forming an airflow channel. At this time, convective heating of the fusible actuator 1 can be achieved by introducing high-temperature airflow from the compressor or turbine. Heating the fusible actuator 1 allows it to return to its initial shape.

[0079] In this embodiment, when the fusible actuating element 1 is heated by electric heating, the heating element 14 is attached to the inner and outer surfaces of the actuating element side plate 102 of the fusible actuating element 1, and the element is heated by heat conduction.

[0080] Preferably, the heating element 14 can be a polyimide heating element with a thickness of only 0.2 mm, and the additional stiffness introduced when it is pasted onto the fuse actuating element 1 is negligible.

[0081] Example 2

[0082] One specific embodiment of the present invention provides an alternative to the fusible actuation element 1 and the heating module in Embodiment 1:

[0083] In this embodiment, as Figure 9 As shown, the fusible actuating element 1 has a sponge-like porous structure.

[0084] like Figure 9 , Figure 10 , Figure 11 As shown, the fuse actuating element 1 has a fan-shaped block structure. Multiple first fuse holes 111 that run through the front end are provided on the front end face of the fuse actuating element 1, and multiple second fuse holes 112 that run through the left and right sides are provided on the left and right sides of the fuse actuating element 1.

[0085] Specifically, the large end of the fusible actuating element 1 engages with the actuating element mounting groove 21 of the actuating element mounting ring 2; the outer ring surface of the small end of the fusible actuating element 1 makes radial compression contact with the actuating element bearing ring surface 441 on the outer side of the bearing ring 44 of the cage structure 4.

[0086] Specifically, such as Figure 10 As shown, the first fuse holes 111 are arranged in a fan-shaped array on the fuse actuating element 1.

[0087] Preferably, the first fuse hole 111 shown is a rectangular hole with rounded corners at the four sides; or, the first fuse hole 111 is an elliptical hole.

[0088] Preferably, such as Figure 10 As shown, the size of the first fuse hole 111 is not uniform, and the diameter of the first fuse hole 111 that is closer to the large end of the fuse actuating element 1 is larger.

[0089] Specifically, such as Figure 10 As shown, the second fuse hole 112 is a fan-shaped groove that penetrates the left and right sides of the fuse actuating element 1; the cross-section of the fan-shaped groove is rectangular, and the corners of the fan-shaped groove are rounded.

[0090] Furthermore, such as Figure 11 As shown, multiple second fuse holes 112 are arranged side by side along the thickness direction of the fuse actuating element 1.

[0091] In this embodiment, multiple first fusible holes 111 longitudinally divide the fusible actuating element 1 into a porous structure, and multiple second fusible holes 112 laterally divide the fusible actuating element 1 into a multi-layered structure. In this embodiment, the multi-layered sheet-like porous structure formed by the first fusible holes 111 and the second fusible holes 112 constitutes the fusible portion of the fusible actuating element 1. In this embodiment, by adjusting the size and number of the first fusible holes 111 and the second fusible holes 112, the load-bearing stiffness of the fusible actuating element 1 can be adjusted to adapt to the usage requirements of different working conditions.

[0092] In this embodiment, the fusible actuation element 1 undergoes plastic deformation under the impact of a high-energy unbalanced load at the moment the fan blades are lost. After heating, it can return to its initial shape.

[0093] Furthermore, in order to achieve the heating repair of the blown actuating element 1 after it has melted, in this embodiment, multiple sets of heating element modules connected in a ring series are used to heat multiple blown actuating elements 1.

[0094] Specifically, such as Figure 12 As shown, each heating element module is composed of multiple heating elements 14 connected in series, and the number of heating elements 14 in a heating element module is equal to the number of the fuse actuating element 1.

[0095] Furthermore, the heating element 14 is attached to the inner wall of the second fuse hole 112 and has the same shape as the side of the second fuse hole 112.

[0096] Preferably, the heating element module is provided in multiple sets, and the number of heating element modules is equal to the number of second fuse holes 112 on the fuse actuating element 1, or the number of heating element modules is twice the number of second fuse holes 112; thereby, heating elements 14 are attached to one or both inner walls of each second fuse hole 112, so that the fuse portion of the fuse actuating element 1 with a multi-layer structure can be heated to promote the repair of plastic deformation.

[0097] In this embodiment, by providing a first fuse hole 111 and a second fuse hole 112 to the fuse actuating element 1, the fuse actuating element 1 can melt (plastic deformation) under the high-energy impact load generated when the fan loses its blades. Then, the plastic deformation of the multi-layer fuse sheet can be restored by multiple sets of heating element modules. The multi-layer porous structure of the fuse actuating element 1 in this embodiment can effectively control the amount of deformation of the melting deformation, and can realize the rapid restoration of the fuse actuating element 1 under the premise of ensuring safe engine deceleration.

[0098] Example 3

[0099] A specific embodiment of the present invention provides a load-bearing method for a fusible repairable load-bearing structure for an aero-engine, employing the fusible repairable load-bearing structure of Embodiment 1 or Embodiment 2, comprising the following steps:

[0100] Step S1: When the engine is running normally, the deformation of the fusible actuating element 1 is within the linear elastic range;

[0101] Step S2: At the moment the fan blade is lost, the fusible actuating element 1 undergoes plastic deformation under the impact of the high-energy unbalanced load, and the radial load is transmitted outward by the squirrel cage structure 4. The fusible actuating element 1 is in the load-bearing fusible state.

[0102] Step S3: After the fusible actuation element 1 is fused, the critical speed of the engine rotor decreases;

[0103] Step S4: After the engine rotor speed is reduced to the windmill speed, the fusible actuating element 1 is heated to restore the plastic deformation of the fusible actuating element 1.

[0104] In this embodiment, during step S1, when the engine is running normally, the vibration load on the engine rotor is relatively small, the deformation of the two side plates of the fusible actuating element 1 is within the linear elastic range, the fusible actuating element 1 is in a state of no plastic deformation, and the annular actuating structure composed of the fusible actuating element 1 and the squirrel cage structure 4 together serve as a load-bearing structure to transmit the radial load generated by the rotating shaft 7 outward.

[0105] Specifically, when using the fusible actuating element 1 of Embodiment 1: the inner ring 103 of the actuating element maintains radial contact with the actuating element bearing ring surface 441 on the cage structure 4, and the radial load is transmitted through the actuating element side plate 102.

[0106] Specifically, when using the fusible actuating element 1 of Embodiment 2: the bottom annular surface of the fusible actuating element 1 maintains radial contact with the actuating element bearing annular surface 441 on the cage structure 4, and the radial load is transmitted through the multi-layer porous plate structure.

[0107] Furthermore, part of the radial load on the shaft 7 and bearing 8 is transmitted to the housing 6 through the fusible actuation element 1, and another part is transmitted to the housing 6 through the inner cage bar 43 and the outer cage bar 42. The fusible actuation element 1 and the squirrel cage structure 4 work together to bear the load. Since the fusible actuation element 1 is made of shape memory alloy, it has good damping properties, and therefore can also effectively suppress the vibration response when the engine is accelerating or decelerating beyond the critical point.

[0108] In this embodiment, in step S2, at the moment the fan blade is lost, the fused part of the fused actuating element 1 undergoes plastic deformation under the impact of high-energy unbalanced load; in the plastic deformation state of the fused actuating element 1, the fused actuating element 1 separates from the actuating element bearing ring 441, and at this time only the squirrel cage structure 4 transmits radial load outward, thereby achieving the bearing fused effect.

[0109] In this embodiment, in step S3, the radial load on the bearing 8 is transmitted to the casing 6 through the inner cage bar 43 and the outer cage bar 42; after the load of the fused actuating element 1 is fused, the load stiffness of the fulcrum is greatly reduced, thereby greatly reducing the critical speed of the engine rotor, ensuring the safe deceleration of the engine rotor with a large imbalance, and ensuring the safety of the engine deceleration process.

[0110] In step S3, when the extreme load caused by the loss of the blade is too large, the limiting ring 3 will make radial contact with the bearing ring 44 of the squirrel cage structure 4, and the load will be directly transmitted outward through the limiting ring 3, so as to avoid irreparable and devastating damage to the fusible actuating element 1 and the squirrel cage structure 4.

[0111] In step S4, after the engine speed is reduced to the windmill speed, the plastic deformation of the fused actuating element 1 can be restored through ventilation convection heating or electric heating element conduction heating. At this time, the fused actuating element 1 re-contacts the actuating element bearing ring surface 441, and the annular actuating structure and the squirrel cage structure 4 jointly transmit radial loads outward, jointly playing a bearing role and achieving the repair effect after bearing failure. After bearing repair, the load on each support point of the engine rotor is redistributed, greatly improving the operating stability and safety of the engine rotor.

[0112] One of the beneficial effects of the technical solution provided in this embodiment compared with the prior art is:

[0113] 1) This invention provides a fusible repairable load-bearing structure for aero-engines. When a fan blade is lost, the fusible actuating element 1 of the load-bearing structure undergoes plastic deformation under high-energy impact, rapidly achieving partial fusing. This significantly reduces the load-bearing stiffness of the support point, thereby lowering the rotor's critical speed and ensuring safe over-critical speed reduction. When the rotor speed decreases to the wind turbine speed, heating the fusible actuating element 1 repairs the deformation of the load-bearing structure, restoring the initial load-bearing effect, redistributing the load, and improving the rotor's operational stability.

[0114] 2) The present invention provides a fusible repairable load-bearing structure for aero engines, which provides load-bearing for the rotor by connecting a ring actuation structure composed of multiple fusible actuation elements 1 and a squirrel cage structure 4 in parallel. When the ring actuation structure fails to fuse, the squirrel cage structure 4 can still provide a certain load-bearing effect for the rotor, thereby avoiding excessively long cantilever sections of the rotor and limiting the swing of the fan shaft to a certain extent.

[0115] 3) This invention provides a fusible repairable load-bearing structure for aero-engines. The fusible actuating element 1 is made of shape memory alloy, which has good damping effect and can replace traditional damping vibration reduction structures for vibration suppression under normal engine operating conditions, thereby reducing engine weight. At the same time, the fusible actuating element 1 has a simple structure and a large side plate surface area, which facilitates the design of its heating system and enables rapid repair after fusing.

[0116] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A fusible repairable load-bearing structure for an aero-engine, used to support the engine rotor, characterized in that, The fusible repairable bearing structure includes: a fusible actuating element (1), an actuating element mounting ring (2), a limiting ring (3), a cage structure (4), and a heating module; the limiting ring (3) is an annular disc structure coaxial with the cage structure (4), and the actuating element mounting ring (2) is a cylindrical structure coaxial with the cage structure (4), and both are located outside the cage structure (4); the actuating element mounting ring (2) is disposed on the side of the limiting ring (3); the limiting ring (3) includes: an outer limiting ring (31) and an inner limiting ring (32); a limiting ring mounting hole (311) is provided on the outer limiting ring (31) for mounting the actuating ring. A limiting ring (3) is installed on the casing (6); the inner ring surface of the inner ring (32) of the limiting ring is separated from the outer ring surface of the cage structure (4); when the fusible actuating element (1) and the cage structure (4) undergo maximum deformation, the limiting ring (3) is in direct contact with the cage structure (4) and the radial load is transmitted through the limiting ring (3); the fusible actuating element (1) is disposed between the cage structure (4) and the actuating element mounting ring (2), and multiple fusible actuating elements (1) are installed at equal intervals on the inner ring surface of the actuating element mounting ring (2); the heating module is used to heat the fusible actuating element (1) after plastic deformation. The fusible actuation element (1) includes: an outer ring (101), a side plate (102), and an inner ring (103); both the outer ring (101) and the inner ring (103) are arc-shaped plate structures; the side plate (102) is connected between the outer ring (101) and the inner ring (103), and two side plates (102) are provided in a mirror-symmetrical manner; the side plate (102) is a thin plate structure with a reverse bow-shaped bend. The outer ring (101) of the actuating element is fitted into the actuating element mounting groove (21) inside the actuating element mounting ring (2) by an interference fit; the inner ring (103) of the actuating element is pressed against the outer ring surface of the cage structure (4); thus achieving radial and circumferential fixation of the fusible actuating element (1); the heating module includes: an air inlet hood (11); the air inlet hood (11) covers the outside of multiple fusible actuating elements (1), and the air inlet hood (11) is used to introduce hot air to heat the fusible actuating element (1); Alternatively, the fusible actuation element (1) is a sponge-like porous structure; the fusible actuation element (1) is generally in the shape of a fan-shaped block, and a plurality of first fusible holes (111) are provided on the front end face of the fusible actuation element (1), and a plurality of second fusible holes (112) are provided on the left and right sides of the fusible actuation element (1); the plurality of first fusible holes (111) divide the fusible actuation element (1) longitudinally into a porous structure, and the plurality of second fusible holes (112) divide the fusible actuation element (1) laterally into a multi-layer structure; at the same time, the heating module is an electric heating element (14) and a wire; the electric heating element (14) heats up after being energized; The fusion actuating element (1) can undergo plastic deformation under high-energy impact loads and can recover its initial shape after heating.

2. The repairable load-bearing structure for aero-engines according to claim 1, characterized in that, The fusion actuating element (1) is made of shape memory alloy.

3. The repairable load-bearing structure for aero-engines according to claim 2, characterized in that, Also includes: Outer retaining ring (5); the outer retaining ring (5) is sleeved on the outside of the squirrel cage structure (4) and can axially limit multiple fusible actuating elements (1).

4. The fusible repairable load-bearing structure for aero-engines according to claim 3, characterized in that, The inner arc surface of the actuator mounting ring (2) is evenly distributed with multiple actuator mounting grooves (21) and actuator positioning bosses (22) in a circumferential direction; the upper end of the fusible actuator (1) is engaged in the actuator mounting groove (21), and the actuator positioning bosses (22) are used to limit the circumferential position of the fusible actuator (1).

5. The repairable load-bearing structure for aero-engines according to claim 1, characterized in that, A through hole (321) is provided on the inner ring (32) of the limiting ring.

6. A load-bearing method for a repairable, fusible load-bearing structure for an aero-engine according to any one of claims 1-5, characterized in that, Includes the following steps: Step S1: When the engine is running normally, the deformation of the fusible actuating element (1) is within the linear elastic range; Step S2: At the moment the fan blade is lost, the fusible actuating element (1) undergoes plastic deformation under the impact of the high-energy unbalanced load, and the radial load is transmitted outward by the squirrel cage structure (4). The fusible actuating element (1) is in the load-bearing fusible state. Step S3: After the fusible actuation element (1) is fused, the critical speed of the engine rotor decreases; Step S4: After the engine rotor speed is reduced to the windmill speed, the fusible actuating element (1) is heated to restore the plastic deformation of the fusible actuating element (1).

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