Compound gear, speed reduction transmission assembly and aircraft

Abstract

The invention discloses a compound gear, a speed reduction transmission assembly and an aircraft, and relates to the field of transmission devices of aircrafts. The compound gear comprises a web plate, the web plate is of a laminated plate structure integrally formed by die pressing of a continuous fiber reinforced composite material, and a center hole is formed in the center of the web plate; the hub is arranged at the center hole in a matched mode, and the hub is a metal piece; the gear ring is connected to the web plate, the gear ring and the hub are coaxially arranged, meshing teeth distributed at intervals in the circumferential direction are arranged on the gear ring, and the gear ring is a metal piece. According to the compound gear disclosed by the embodiment of the invention, the web plate between the gear ring and the hub adopts the laminated plate structure integrally molded by the continuous fiber reinforced composite material through mould pressing, so that high strength and durability are kept while the weight is reduced, and the flight burden can be reduced.

Description

Technical Field

[0001] The present invention relates to the field of transmission devices for aircraft, and in particular to a composite gear, a reduction transmission assembly and an aircraft. Background Art

[0002] The performance requirements of the aircraft's transmission system are relatively high. For example, the main task of the helicopter transmission system is to transfer the power of the power system to the rotor system. At present, the main load-bearing components in the transmission system of the helicopter, the components with complex forces, and the components that bear dynamic loads and impact loads are still mainly made of metal materials, resulting in a large weight share, which affects the performance of the helicopter and the goal of lightweighting. Therefore, the structure of the aircraft's transmission system has room for improvement. Summary of the invention

[0003] A first aspect of the present invention aims to provide a compound gear.

[0004] A second aspect of the present invention aims to provide a reduction transmission assembly having the above-mentioned composite gear.

[0005] A third aspect of the present invention aims to provide an aircraft having the above-mentioned reduction transmission assembly.

[0006] According to the first aspect of the present invention, the composite gear of continuous fiber reinforced composite material-metal material is used in an aircraft. The composite gear comprises: a web, the center of which has a center hole; a hub, which is fitted at the center hole, and is a metal part; a gear ring, which is connected to the web, is coaxially arranged with the hub, is provided with meshing teeth spaced circumferentially, and is a metal part.

[0007] The web is a laminate structure formed by compression molding of continuous fiber reinforced composite materials, specifically: the web includes multiple layers of carbon fiber prepregs distributed in sequence along the thickness direction of the web, the ply angles of the multiple layers of the carbon fiber prepregs are alternately 0° / 90° and ±45°, a layer of epoxy resin structural adhesive film is laid between each two adjacent layers of the carbon fiber prepregs, and compression molding is adopted after the plying is completed; the thickness range of each layer of the carbon fiber prepreg is 0.127m m-0.305mm, the tensile strength range is 4700MPa-5100MPa, and the tensile modulus range is 220GPa-240GPa; the thickness range of the epoxy resin structural adhesive film is 0.127mm-0.254mm, and the shear strength range is 30MPa-40Mpa; the thickness of the web is at least 18mm; the torsional strength range of the web is 100MPa-150MPa, and the bending strength range is 170MPa-220MPa.

[0008] According to the composite gear of the embodiment of the present invention, a continuous fiber reinforced composite material is used as the web between the gear ring and the hub to achieve the goal of lightweight. At the same time, the metal gear ring provides high hardness and wear resistance to ensure reliability during high torque transmission. This composite gear can reduce the flight burden and reduce flight energy consumption.

[0009] According to the composite gears of some embodiments of the present invention, the web includes at least three layers of sub-plates stacked along the axial direction, and each layer of the sub-plates is integrally formed by compression molding of continuous fiber reinforced composite materials; the thickness of each layer of the sub-plates is at least 6 mm, and the number of carbon fiber prepreg fabrics on each layer of the sub-plates is at least 30 layers.

[0010] Specifically, the gear ring is provided with a flange extending radially inward. The web includes: a first sub-plate, the first sub-plate is located on one axial side of the flange; a second sub-plate, the second sub-plate is located in the space surrounded by the flange; and a third sub-plate, the third sub-plate is located on the other axial side of the flange; wherein the flange is sandwiched between the first sub-plate and the third sub-plate, and the first sub-plate is at least connected to the third sub-plate.

[0011] Furthermore, the inner circumference of the flange is a non-cylindrical surface, the outer circumference of the second sub-plate is consistent in shape with the inner circumference of the flange, and the outer circumference of the second sub-plate is in contact with and fits with the inner circumference of the flange.

[0012] In some specific embodiments, the first sub-plate, the flange, and the third sub-plate are provided with corresponding through holes in sequence; the composite gear further includes: fasteners that fit into the through holes, and the fasteners are connected to the first sub-plate, the flange, and the third sub-plate.

[0013] Furthermore, the flange includes a plurality of triangular areas arranged in sequence along the circumferential direction, a through hole is provided on the midline of each triangular area, the top angle of each triangular area is arranged toward the hub and is rounded, and the sides of two adjacent triangular areas are connected by an arc transition.

[0014] In some specific embodiments, the composite gear further comprises: an adhesive layer, wherein the adhesive layer is bonded between the gear ring and the web.

[0015] Specifically, the center hole is a non-circular hole, the shape of the outer circumference of the hub is consistent with the shape of the inner circumference of the center hole, and the outer circumference of the hub is in contact with the inner circumference of the center hole.

[0016] According to an embodiment of the second aspect of the present invention, the reduction transmission assembly comprises: a casing, wherein an assembly cavity is defined in the casing, and an input shaft hole and an output shaft hole are provided on the casing; an input gear, wherein the input gear is assembled at the input shaft hole; an output gear, wherein the output gear is assembled at the output shaft hole, and the output gear is meshed with the input gear in the assembly cavity; wherein at least one of the input gear and the output gear is the compound gear described in the embodiment of the first aspect of the present invention.

[0017] An aircraft according to an embodiment of the third aspect of the present invention comprises: a power system; a reduction transmission assembly, wherein the reduction transmission assembly is the reduction transmission assembly according to the embodiment of the second aspect of the present invention, wherein the input gear is connected to the power system; and a rotor system, wherein the rotor system is connected to the output gear. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is an isometric view of a compound gear according to some embodiments of the present invention; Figure 2 An exploded view of a composite gear according to some embodiments of the present invention; Figure 3 Schematic cross-sectional views of compound gears according to some embodiments of the present invention; Figure 4 A front view of a gear ring according to some embodiments of the present invention; Figure 5 for Figure 4 a side view of the ring gear shown; Figure 6 for Figure 4 a rear view of the ring gear shown; Figure 7 A front view of a web according to some embodiments of the present invention; Figure 8 for Figure 7 a side view of the web shown; Fig. 9 for Figure 7 a perspective view of the web shown; Fig.10 for Figure 7 A cross-sectional view of the web along AA shown; Fig.11 for Figure 8 A cross-sectional view along BB of the web shown; Fig.12 A front view of a wheel hub according to some embodiments of the present invention; Fig.13 for Fig.12 a side view of the hub shown; Fig.14 for Fig.12 a cross-sectional view of the hub shown; Fig.15 for Fig.12 a perspective view of the hub shown; Fig.16 An adhesive layer between the gear ring and the web in some embodiments of the present invention; Fig.17 An adhesive layer between the hub and the web in some embodiments of the present invention; Fig.18 A schematic structural diagram of a casing in some embodiments of the present invention; Fig.19 An exploded view of a casing according to some embodiments of the present invention; Fig. 20 It is a schematic diagram of the structure of a reduction transmission assembly in some embodiments of the present invention; Fig.21 Schematic diagram of the internal structure of a reduction transmission assembly according to some embodiments of the present invention; Fig. 22 A schematic diagram of the structure of an aircraft according to some embodiments of the present invention; Fig.23 A schematic diagram of the coordination of a reduction transmission assembly, a power system, and a rotor system of an aircraft according to some embodiments of the present invention; Fig.24 The present invention is a schematic diagram of the connection structure of the reduction transmission assembly, the power system and the rotor system of an aircraft in some embodiments of the present invention.

[0019] Reference numerals: Aircraft 10,000; Reduction transmission assembly 1000; Compound gear 100; Web 13, center hole 13-10, first center hole 13-1, second center hole 13-2, third center hole 13-3; Sub-board 130, first sub-board 1301, second sub-board 1302, third sub-board 1303; Wheel hub 15; Ring gear 40, meshing teeth 41, flange 44, triangular area 441; Fastener 50, adhesive layer 60; Perforation 701; Casing 200, input shaft hole 201, output shaft hole 202, assembly cavity 203; Input gear 300, output gear 400; Power system 2000, rotor system 3000. DETAILED DESCRIPTION

[0020] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0021] In the description of the present invention, it should be understood that the terms "upper", "lower", "inner", "outer", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation and be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0022] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0023] Reference below Figure 1 - Fig.17 A continuous fiber reinforced composite material-metal material hybrid composite gear 100 according to an embodiment of the first aspect of the present invention is described.

[0024] According to the composite gear 100 of the first aspect of the present invention, the composite gear 100 is used in an aircraft 10000 .

[0025] like Figure 1 - Figure 2 As shown, the composite gear 100 according to the first embodiment of the present invention includes: a web 13 , a hub 15 and a ring gear 40 .

[0026] The web 13 is a continuous fiber reinforced composite material member.

[0027] The use of continuous fiber reinforced composite material as the web 13 of the composite gear 100 has the following advantages compared to traditional metal materials: First, the density of the continuous fiber reinforced composite part is lower than that of a general metal part, which means that the continuous fiber reinforced composite part can reduce the weight of the composite gear 100. For a weight-sensitive aircraft 10000 such as a helicopter, weight reduction can directly translate into higher payload, longer range or better fuel economy.

[0028] Secondly, the continuous fiber reinforced composite material provides relatively excellent specific strength (ie, strength / weight ratio) and specific stiffness (ie, stiffness / weight ratio), which enables the web 13 to maintain good mechanical properties even under high-intensity load conditions.

[0029] Furthermore, the continuous fiber reinforced composite material also has good fatigue resistance, which is very important for the transmission system of a helicopter that needs to run for a long time and withstand periodic loads. Having high fatigue resistance can enhance the reliability and durability of the composite gear 100, thereby ensuring that the aircraft 10000 has a longer service life and lower maintenance frequency.

[0030] In addition, the continuous fiber reinforced composite material also has a certain corrosion resistance, which helps to increase the service life of the web 13 and reduce the probability of its corrosion, correspondingly extending the service life of the composite gear 100 and reducing maintenance costs.

[0031] The center of the web 13 has a center hole 13-10, and the hub 15 is fitted in the center hole 13-10. The ring gear 40 is connected to the web 13, and the ring gear 40 is coaxially arranged with the hub 15. The ring gear 40 is provided with meshing teeth 41 distributed at intervals along the circumferential direction. The hub 15 is a metal part, and the ring gear 40 is also a metal part.

[0032] It can be known that the axis of the ring gear 40 coincides with that of the wheel hub 15, which can ensure the accuracy and stability of the transmission.

[0033] The gear ring 40 is provided with meshing teeth 41 spaced apart along the circumferential direction. The meshing teeth 41 are the parts that mesh with other gears or transmission components. The transmission of power and torque can be achieved through the meshing teeth 41 .

[0034] The gear ring 40 is a metal part. Specifically, when the metal gear ring 40 is used in the transmission system of the aircraft 10000, the metal gear ring 40 has high strength, high hardness and good wear resistance. Therefore, it can withstand the friction generated by high load and high-speed operation, thereby ensuring the long-term stable operation of the transmission system.

[0035] Optionally, the hub 15, the gear ring 40 and the web 13 may be connected by welding, bolting or adhesive connection, or a combination thereof. For example, in some solutions, the gear ring 40 and the web 13 are connected by bolts. Alternatively, in some other solutions, the gear ring 40 and the web 13 are connected by a combination of bolting and adhesive connection.

[0036] The web 13 is a laminate structure formed by compression molding of continuous fiber reinforced composite materials.

[0037] In the present application, the web 13 includes multiple layers of carbon fiber prepregs distributed in sequence along the thickness direction of the web 13. The ply angles of the multiple layers of carbon fiber prepregs are alternately 0° / 90° and ±45°, and a layer of epoxy resin structural adhesive film is laid between each two adjacent layers of carbon fiber prepregs, and after the ply is completed, molding is performed by molding and curing.

[0038] Specifically, each layer of carbon fiber prepreg is a T700-3K plain reinforced fiber layer. Specifically, the raw material of Tianjin Anglin Maofeng High-tech Materials Co., Ltd. can be selected, and the model is T700-3K plain reinforced fiber. The epoxy resin structural adhesive film specifically selects the raw material of Shanghai Hongsi New Materials Technology Co., Ltd., and the model is HX-F168.

[0039] Here, T700 is a model of carbon fiber. Carbon fiber is a new type of fiber material with high strength and high modulus fiber with a carbon content of more than 90%. The "T" in T700 represents the tensile strength classification of carbon fiber, and the number "700" means that the tensile strength of carbon fiber is about 700MPa. T700 fiber cloth has high strength and can withstand large tensile forces. Its modulus is high, which means that the material has a strong ability to resist deformation when subjected to force.

[0040] In the field of fiber cloth such as carbon fiber cloth, "K" is a unit that represents the number of filaments in a fiber bundle. "3K" means that a bundle of fibers in this fiber cloth is composed of 3,000 filaments. For example, in the production process of carbon fiber cloth, these filaments are bundled together to form a fiber bundle with certain properties.

[0041] Among them, the thickness of each layer of carbon fiber prepreg cloth ranges from 0.127mm to 0.305mm, the tensile strength ranges from 4700MPa to 5100MPa, and the tensile modulus ranges from 220GPa to 240GPa.

[0042] The thickness of the epoxy resin structural adhesive film ranges from 0.127mm to 0.254mm, and the shear strength ranges from 30MPa to 40MPa.

[0043] The total thickness of the web 13 is at least 18 mm, and the web 13 has a torsional strength in the range of 100 MPa-150 MPa and a bending strength in the range of 170 MPa-220 MPa.

[0044] To further facilitate understanding of the structure of the web 13 of the present application, the web 13 of some embodiments of the present application may be formed by compression molding after all the materials are laid up, and the process shown in Table 1 below may be selected: Table 1

[0045] That is to say, after the carbon fiber prepreg and epoxy resin structural adhesive film are laid, the compression molding is completed in five stages.

[0046] The first stage lasts 60 minutes, and the mold is closed at 80°C without pressure; The second stage lasts for 60 minutes. On the basis of 80°C, the temperature is increased at a rate of 1°C per minute until the temperature reaches 60 minutes. During this process, the molding pressure is maintained at 0.3MPa. The third stage lasted for 180 minutes, maintaining a temperature of 140°C and a molding pressure of 0.3 MPa; The fourth stage lasts for 60 minutes. Based on the temperature of 140°C, the temperature is lowered at a rate of 1°C per minute until the temperature drops for 60 minutes. During this process, the molding pressure is maintained at 0.3MPa. The first stage lasts 10 minutes and is carried out at 80°C without pressure.

[0047] In this way, the web 13 required for this application can be obtained.

[0048] In some embodiments, the web 13 may be a unitary plate.

[0049] In other embodiments, Figure 2 and Figure 3 As shown, the web 13 includes at least three layers of sub-plates 130 stacked in the axial direction, and each layer of sub-plates 130 is molded as a whole by continuous fiber reinforced composite material compression molding. The thickness range of each layer of sub-plates 130 is at least 6 mm, and there are at least 30 layers of carbon fiber prepreg on each layer of sub-plates 130. In this way, after the web 13 is layered, the thickness of the single-layer sub-plate 130 is reduced, which is convenient for installation and connection with the hub 15 and the ring gear 40, and convenient for the web 13 to be physically connected to the hub 15 and the ring gear 40.

[0050] Here, each layer of sub-panels 130 is integrally formed by compression molding of continuous fiber reinforced composite materials, which means that each layer of sub-panels 130 is an integrally formed panel formed by compression molding of continuous fiber reinforced composite materials.

[0051] Specifically, each layer of sub-plate 130 includes multiple layers of carbon fiber prepreg distributed in sequence along the thickness direction. The ply angles of the multiple layers of carbon fiber prepreg are alternately 0° / 90° and ±45°. A layer of epoxy resin structural adhesive film is laid between each two adjacent layers of carbon fiber prepreg, and after the ply is completed, it is molded and cured. Among them, the thickness of each layer of carbon fiber prepreg is in the range of 0.127mm-0.305mm, the tensile strength is in the range of 4700MPa-5100MPa, and the tensile modulus is in the range of 220GPa-240GPa. The thickness of the epoxy resin structural adhesive film is in the range of 0.127mm-0.254mm, and the shear strength is in the range of 30MPa-40Mpa.

[0052] For example, in some specific embodiments, Figure 2-Figure 6 As shown, a flange 44 extending radially inward is provided on the gear ring 40. The web 13 includes: a first sub-plate 1301, a second sub-plate 1302 and a third sub-plate 1303, wherein the first sub-plate 1301 is located on one axial side of the flange 44. The second sub-plate 1302 is located in the space surrounded by the flange 44, and the third sub-plate 1303 is located on the other axial side of the flange 44.

[0053] The flange 44 is sandwiched between the first sub-board 1301 and the third sub-board 1303 , and the first sub-board 1301 is at least connected to the third sub-board 1303 .

[0054] With such arrangement, the flange 44 is clamped between the first sub-plate 1301 and the third sub-plate 1303, the contact area between the web 13 and the gear ring 40 is large, and the two can be strictly limited in the axial, circumferential and radial directions, which is beneficial to improve the structural strength and rigidity of the connection between the two and reduce the probability of disengagement between the two.

[0055] Specifically, Figure 2 and Figure 6 As shown, the inner peripheral surface of the flange 44 is a non-cylindrical surface. Figure 2 and Fig.11 As shown, the outer circumference of the second sub-plate 1302 is consistent in shape with the inner circumference of the flange 44 , and the outer circumference of the second sub-plate 1302 is in contact with the inner circumference of the flange 44 .

[0056] The non-cylindrical surface setting can provide a larger contact area, thereby improving the uniformity and stability of torque transmission.

[0057] In this way, when one of the ring gear 40 and the wheel hub 15 rotates, the outer circumference of the second sub-plate 1302 and the inner circumference of the flange 44 are in surface contact, driving the other of the ring gear 40 and the wheel hub 15 to rotate. The transmission of the driving force between the two can be at least partially transmitted through the surface contact between the outer circumference of the second sub-plate 1302 and the inner circumference of the flange 44. The large circumference of the contact surface can disperse the driving force in the circumferential direction, thereby reducing the force per unit area, reducing the concentrated stress, and improving the transmission reliability.

[0058] Here, the shape of the inner circumference of the flange 44 may not be limited, and the projection of the inner circumference of the flange 44 on the end surface of the flange 44 may be an ellipse, a polygon, etc., which is not limited here.

[0059] In some specific embodiments, Figure 4 and Figure 6 As shown, the flange 44 includes a plurality of triangular areas 441 arranged in sequence along the circumferential direction, so that the circumference of the contact surface is longer. Optionally, the top of each triangular area 441 is an arc angle, and optionally, adjacent triangular areas 441 are connected by arc transition. In this way, the concentrated stress on the flange 44 can be further reduced and its load capacity can be increased.

[0060] In some specific embodiments, the inner circumference of the flange 44 is a sinusoidal directrix cylinder, that is, the inner circumference of the flange 44 is a sinusoidal curve surface after being unfolded.

[0061] Alternatively, the inner circumferential surface of the flange 44 may also adopt other centrally symmetrical but non-cylindrical shapes.

[0062] It is understandable that the central symmetric pattern can make the two contact surfaces have a more uniform stress distribution when connected. Due to the characteristics of the central symmetric pattern, they can evenly distribute the stress to the entire contact surface when subjected to the same external force, thereby avoiding local wear or damage caused by stress concentration at one or several points.

[0063] Since the stress distribution is more uniform, the design of the central symmetrical pattern can improve the connection strength between the web 13 and the ring gear 40. This uniform stress distribution reduces material fatigue caused by stress concentration, thereby extending the service life of the composite gear 100. In addition, the uniform stress distribution also helps to reduce vibration and noise caused by unbalanced forces, thereby helping to improve the running smoothness of the transmission system of the aircraft 10000.

[0064] In the present application, the outer circumference of the second sub-plate 1302 and the inner circumference of the flange 44 may have the same shape or may have a slight difference, as long as the two are compatible.

[0065] Furthermore, if Figure 2-Figure 11As shown, corresponding through holes 701 are sequentially provided on the first sub-plate 1301, the flange 44, and the third sub-plate 1303. The composite gear 100 further includes: a fastener 50 matched at the through hole 701, and the fastener 50 is connected to the first sub-plate 1301, the flange 44, and the third sub-plate 1303. That is, the flange 44 is sandwiched between the first sub-plate 1301 and the third sub-plate 1303, and is also passed through the first sub-plate 1301, the flange 44, and the third sub-plate 1303 through the fastener 50. With such a configuration, when the composite gear 100 is subjected to torque, it is beneficial to distribute the torque force to the first sub-plate 1301, the flange 44, and the third sub-plate 1303 through the fastener 50, thereby reducing the probability of delamination between any two layers of plates and improving the overall torsional strength.

[0066] Alternatively, if Figure 2-Figure 11 As shown, the flange 44 includes a plurality of triangular areas 441 arranged in sequence along the circumferential direction, a through hole 701 is arranged on the midline of each triangular area 441, the top angle of each triangular area 441 is arranged toward the hub 15 and is rounded, and the sides of two adjacent triangular areas 441 are connected by a circular arc transition. In this way, the positions of the through holes 701 are evenly distributed, the load is evenly loaded, and the generation of concentrated stress can be reduced, which is conducive to improving the overall torsional strength and bending strength.

[0067] A plurality of fasteners 50 are connected between the web 13 and the gear ring 40. These fasteners 50 are used to ensure a firm connection between the web 13 and the gear ring 40 to prevent relative displacement or looseness during high torque transmission.

[0068] Optionally, the fastener 50 may be a rivet, or other types of connecting members, such as a screw, a pin, etc.

[0069] In some embodiments, rivets are used as an example for description. The rivets are used to achieve a fixed connection between the web 13 and the gear ring 40 by upsetting the two ends to form a head. The rivets pass through the web 13 and the gear ring 40 through pre-drilled holes, and the other side is upset to form a head by hammering or other tools, thereby achieving a fixed connection. This riveting method is simple and reliable, can be completed without complex tools or equipment, and is also easy to maintain and repair.

[0070] In some optional embodiments, the plurality of fasteners 50 are distributed along the circumferential direction with the axis of the gear ring 40 as the center. This means that the plurality of fasteners 50 are arranged along the circumferential direction of the gear ring 40, and the distances between each fastener 50 are substantially equal. This arrangement enables the fasteners 50 to be distributed symmetrically around the axis of the gear ring 40, ensuring that the connection points between the web 13 and the gear ring 40 are evenly distributed in the circumferential direction.

[0071] By evenly distributing the plurality of fasteners 50 along the circumferential direction, it is possible to ensure that the contact surface between the web 13 and the gear ring 40 is evenly stressed in the circumferential direction. This even stress reduces the phenomenon of local stress concentration and avoids material fatigue or damage caused by excessive pressure on a single point.

[0072] At the same time, the circumferentially distributed fasteners 50 can improve the stability of the connection between the web 13 and the ring gear 40. Since the fasteners 50 are evenly distributed on the circumference, they can share the external force together, further improve the torque of the ring gear 40, and ensure that the composite gear 100 can better disperse the stress when subjected to high torque, thereby extending the service life of the entire gear system.

[0073] Optionally, the number of fasteners 50 is not specifically limited and can be further adjusted according to user needs.

[0074] In some embodiments, Figure 7 As shown, the center hole 13-10 of the web 13 is a non-circular hole. Figure 12-Figure 15 As shown, the shape of the outer circumference of the hub 15 is consistent with the shape of the inner circumference of the center hole 13-10. The outer circumference of the hub 15 is in contact with the inner circumference of the center hole 13-10.

[0075] Here, when the web 13 is a multi-layer sub-board 130, as shown in FIG. Fig. 9 As shown, the center of each layer of sub-plate 130 is provided with a hole corresponding to the hub 15. For example, a first center hole 13-1 is provided at the center of the first sub-plate 1301, a second center hole 13-2 is provided at the center of the second sub-plate 1302, and a third center hole 13-3 is provided at the center of the third sub-plate 1303. The shapes of the first center hole 13-1, the second center hole 13-2, and the third center hole 13-3 all match the shape of the outer circumference of the hub 15.

[0076] like Figure 12-Figure 15 As shown, the middle section of the hub 15 forms a spline to assemble the first sub-plate 1301, the second sub-plate 1302, and the third sub-plate 1303. Shoulders are formed on the two layers of the spline to assemble bearings and the like.

[0077] In some embodiments, Fig.16 As shown, the composite gear 100 further includes an adhesive layer 60 , which is bonded between the ring gear 40 and the web 13 .

[0078] The adhesive layer 60 is located between the gear ring 40 and the web 13. The adhesive layer 60 serves to firmly bond the two components together.

[0079] On the one hand, by adding the adhesive layer 60, the connection strength between the ring gear 40 and the web 13 is enhanced to a certain extent. The adhesive can fill the tiny gap and eliminate some potential looseness, thereby improving the reliability of the composite gear 100. Especially under some high torque transmission and vibration conditions, the adhesive layer 60 can prevent the relative displacement or looseness between the ring gear 40 and the web 13, and improve the connection strength between the two.

[0080] On the other hand, the adhesive layer 60 can play a role in uniform stress distribution. Since the adhesive can fill the irregularities that may occur on the contact surface, the stress is more evenly distributed on the contact surface, thereby reducing local stress concentration.

[0081] Furthermore, the adhesive layer 60 can also provide a certain sealing effect to prevent foreign matter from entering between the contact surfaces, protect the internal structure from being polluted, and further extend the service life of the composite gear 100.

[0082] In some optional embodiments, the thickness of the adhesive layer 60 is 0.1 mm-0.2 mm.

[0083] For example, the thickness of the adhesive layer 60 is 0.1 mm, 0.12 mm, 0.15 mm, 0.17 mm, 0.2 mm, etc. Here, the thickness of the adhesive layer 60 is controlled within 0.1 mm-0.2 mm, which can provide sufficient bonding strength to ensure the tight bonding between the ring gear 40 and the web 13, and prevent relative sliding or loosening under high torque transmission and vibration conditions. At the same time, the impact on the overall size and weight of the composite gear 100 is minimized.

[0084] Of course, the present application solution may not be limited thereto. In some embodiments, such as Fig.17 As shown, an adhesive layer 60 may also be provided between the hub 15 and the web 13 .

[0085] The reduction transmission assembly 1000 according to the second embodiment of the present invention comprises: a casing 200, an input gear 300 and an output gear 400. Fig.18 - Fig. 20 The casing 200 defines an assembly cavity 203, and the casing 200 is provided with an input shaft hole 201 and an output shaft hole 202. The input gear 300 is assembled at the input shaft hole 201. The output gear 400 is assembled at the output shaft hole 202, and the output gear 400 meshes with the input gear 300 in the assembly cavity 203. Fig.21 , wherein at least one of the input gear 300 and the output gear 400 is the composite gear 100 according to the first embodiment of the present invention.

[0086] In the above technical solution, the casing 200 defines an assembly cavity 203. The assembly cavity 203 is used to accommodate multiple components of the reduction transmission assembly 1000, such as the input gear 300, the output gear 400, etc. The assembly cavity 203 provides a safe space for the reduction transmission assembly 1000 to ensure that it can run smoothly during operation.

[0087] The casing 200 is provided with an input shaft hole 201 and an output shaft hole 202. The input shaft hole 201 is used to install the input gear 300, and the output shaft hole 202 is used to install the output gear 400. The arrangement of these holes needs to ensure that the shaft can be smoothly inserted and firmly fixed inside the casing 200 through supporting structures such as bearings.

[0088] The input gear 300 is assembled at the input shaft hole 201. Optionally, the input gear 300 is mounted on the input shaft through a keyway and supported in the input shaft hole 201 in the casing 200 through a bearing. Such a connection method can ensure that the input gear 300 does not wobble when rotating.

[0089] The output gear 400 meshes with the input gear 300 in the assembly cavity 203. This means that the two gears can transmit torque through the mutual meshing of the gear teeth when rotating. The rotation of the input gear 300 is transmitted to the output gear 400 through meshing, thereby achieving a deceleration or acceleration effect.

[0090] At least one of the input gear 300 and the output gear 400 is the composite gear 100 according to the first embodiment of the present invention.

[0091] When the input gear 300 is a composite gear 100, the composite gear 100 with a lightweight advantage can reduce the total weight of the reduction transmission assembly 1000, thereby reducing the inertia of the moving parts, so that the input gear 300 requires less energy when rotating, thereby improving the transmission efficiency. At the same time, this composite gear 100 has a metal hub 15 and a ring gear 40, which can provide higher hardness and wear resistance, ensuring the reliability of the composite gear 100 during high torque transmission. Therefore, by combining a lightweight design with a high-strength metal ring gear 40, the composite gear 100 can maintain stable operation when subjected to high torque, thereby improving the overall reliability of the reduction transmission assembly 1000.

[0092] When the output gear 400 is a composite gear 100, the weight of the reduction gear assembly 1000 is reduced due to the use of a lightweight composite gear 100, and the inertia of the output gear 400 is also reduced. This means that less power is required when starting and stopping, which can reduce energy loss to a certain extent and improve the response speed and efficiency of the system.

[0093] In order to further reduce the total weight of the reduction transmission assembly 1000 , reduce inertia, improve transmission efficiency, and ensure reliability under high torque transmission conditions, in some optional embodiments, both the input gear 300 and the output gear 400 are composite gears 100 .

[0094] like Fig. 22 - Fig.24 As shown, the aircraft 10000 according to the third embodiment of the present invention comprises: a power system 2000, a reduction transmission assembly 1000 and a rotor system 3000. The reduction transmission assembly 1000 is the reduction transmission assembly 1000 according to the second embodiment of the present invention, wherein the input gear 300 is connected to the power system 2000. The rotor system 3000 is connected to the output gear 400.

[0095] In the above technical solution, the input gear 300 is connected to the power system 2000 and is responsible for transmitting the power generated by the engine to the reduction transmission assembly 1000. Fig.23 , the power system 2000 is connected to the input gear 300 through the input shaft hole 201. When the input gear 300 is a composite gear 100, the lightweight characteristics of the composite gear 100 can be utilized to reduce the inertia of the input gear 300, so that the power transmission is faster and more efficient. At the same time, due to the lightweight design of the composite gear 100, it also helps to reduce energy loss during the start and stop process, and improve the response speed and efficiency of the power system 2000.

[0096] The rotor system 3000 is connected to the output gear 400 and is responsible for transmitting the decelerated power to the rotor blades. Fig.24 , the rotor system 3000 is connected to the output gear 400 through the output shaft hole 202. By setting the composite gear 100 with a higher degree of lightness as the output gear 400, the output gear 400 can be made more efficient in transmitting power, thereby reducing energy loss. At the same time, by reducing the weight and inertia of the output gear 400, the response speed of the rotor system 3000 can be improved, so that the rotor blades can reach the required rotation speed faster, thereby improving the maneuverability and efficiency of the aircraft 10000.

[0097] In summary, by using the composite gear 100 in the key transmission components of the aircraft 10000, the weight of the entire aircraft 10000 can be reduced. This is very beneficial to improving the fuel efficiency and endurance of the aircraft 10000. Moreover, the high strength of the composite gear 100 also ensures reliability under high torque transmission conditions. It reduces maintenance frequency and costs, and improves the overall reliability of the aircraft 10000. In addition, the high hardness and wear resistance of the metal gear ring 40 enables the composite gear 100 to maintain good performance under high torque conditions, thereby extending the service life of the reduction transmission assembly 1000 and the entire aircraft 10000.

[0098] It is worth noting that according to the embodiment of the present application, the type of the aircraft 10000 is not limited, and it can be a helicopter or a drone, etc.

[0099] The composite gear 100 according to the embodiment of the present invention is described in detail below with reference to a specific embodiment. It should be understood that the following description is only an exemplary description and is not a specific limitation of the present invention.

[0100] Example 1 Reference Figure 1 The composite gear 100 includes a web 13 , a hub 15 and a gear ring 40 .

[0101] The web 13 is a laminate structure formed by compression molding of a continuous fiber reinforced composite material.

[0102] Reference Figure 2 The web 13 is connected between the ring gear 40 and the wheel hub 15. The ring gear 40 and the wheel hub 15 are coaxially arranged. The ring gear 40 is provided with meshing teeth 41 distributed at intervals along the circumferential direction. The ring gear 40 and the wheel hub 15 are metal parts.

[0103] The web 13 is formed by continuous fiber reinforced composite material compression molding, and includes multiple layers of carbon fiber prepregs distributed in sequence along the thickness direction of the web 13. Each layer of carbon fiber prepreg is a T700-3K plain weave reinforced fiber layer. The laying angles of the multiple layers of carbon fiber prepregs are alternately 0° / 90° and ±45°. A layer of epoxy resin structural adhesive film is laid between each two adjacent layers of carbon fiber prepreg. The layup design structure of the web 13 is shown in Table 2.

[0104] Table 2 Layer design in the web 13 of the present invention

[0105] In Example 1, each layer of carbon fiber prepreg has a thickness of 0.2 mm, a tensile strength of 4900 MPa, and a tensile modulus of 230 GPa. The epoxy resin structural adhesive film has a thickness of 0.2 mm, a shear strength of 40 MPa, and a thickness of 18 mm for the web 13.

[0106] In Example 1, the processing method of the web 13 is carried out according to the process in Table 1 above.

[0107] The structural parameters obtained for the web 13 are: torsional strength in the range of 100 MPa-150 MPa, and bending strength in the range of 170 MPa-220 MPa.

[0108] Comparative Example 1 The structure of the composite gear in comparative example 1 is substantially the same as that of the composite gear 100 in embodiment 1, except that the ply design structure of the web in the comparative example is as shown in Table 3.

[0109] Table 3 Laying design of web in comparative example 1

[0110] Comparative Example 2 The structure of the composite gear in Comparative Example 2 is substantially the same as that of the composite gear 100 in Example 1, except that the ply design structure of the web in the comparative example is as shown in Table 4.

[0111] Table 4 Laying design of web in comparative example 2

[0112] Performance Testing 1. Performance testing methods.

[0113] (1) Use an electronic universal testing machine to test the tensile, compression, bending and other mechanical properties of the specimen; (2) Use a torsion testing machine to test the torsion performance of the sample.

[0114] 2. Performance test results

[0115] (1) Interlaminar strength performance Example 1>Comparative Example 1, the interlayer strength performance of Example 1 and Comparative Example 2 is equivalent; (2) Torsional strength performance Example 1>Comparative Example 1>Comparative Example 2; (3) Bending strength performance Example 1>Comparative Example 1>Comparative Example 2.

[0116] Other components of the composite gear 100 according to the embodiment of the present invention, such as the reduction transmission assembly 1000 and the aircraft 10000, and operations thereof are known to those skilled in the art and will not be described in detail herein.

[0117] In the description of this specification, the description with reference to the terms "embodiment", "example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0118] Although embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A composite gear of continuous fiber reinforced composite material and metal material, characterized in that: The composite gear is used in an aircraft, and the composite gear comprises: a web having a center hole at its center; A wheel hub, the wheel hub is fitted at the center hole, and the wheel hub is a metal part; A gear ring, the gear ring is connected to the web, the gear ring is coaxially arranged with the wheel hub, the gear ring is provided with meshing teeth distributed at intervals along the circumferential direction, and the gear ring is a metal part; The web is a laminate structure formed by compression molding of continuous fiber reinforced composite materials, specifically: The web comprises multiple layers of carbon fiber prepregs distributed in sequence along the thickness direction of the web, the ply angles of the multiple layers of the carbon fiber prepregs are alternately 0° / 90° and ±45°, a layer of epoxy resin structural adhesive film is laid between each two adjacent layers of the carbon fiber prepregs, and after the ply is completed, compression curing is adopted; The thickness of each layer of the carbon fiber prepreg is in the range of 0.127 mm to 0.305 mm, the tensile strength is in the range of 4700 MPa to 5100 MPa, and the tensile modulus is in the range of 220 GPa to 240 GPa. The epoxy resin structural adhesive film has a thickness range of 0.127 mm to 0.254 mm and a shear strength range of 30 MPa to 40 MPa; The thickness of the web is at least 18 mm; The obtained web has a torsional strength ranging from 100 MPa to 150 MPa and a bending strength ranging from 170 MPa to 220 MPa.

2. The continuous fiber reinforced composite material-metal material hybrid composite gear according to claim 1, characterized in that: The web plate comprises at least three layers of sub-plates stacked in the axial direction, and each layer of the sub-plates is integrally formed by compression molding of a continuous fiber reinforced composite material; The thickness of each layer of the sub-board is at least 6 mm, and the number of carbon fiber prepreg fabrics on each layer of the sub-board is at least 30.

3. The continuous fiber reinforced composite material-metal material hybrid composite gear according to claim 2, characterized in that: The gear ring is provided with a flange extending radially inward; The web comprises: A first sub-plate, the first sub-plate being located on one axial side of the flange; a second sub-board, the second sub-board being located in the space surrounded by the flange; a third sub-plate, the third sub-plate being located at the other axial side of the flange; The flange is sandwiched between the first sub-board and the third sub-board, and the first sub-board is at least connected to the third sub-board.

4. The continuous fiber reinforced composite material-metal material hybrid composite gear according to claim 3, characterized in that: The inner circumference of the flange is a non-cylindrical surface, the outer circumference of the second sub-plate is consistent with the inner circumference of the flange, and the outer circumference of the second sub-plate is in contact with the inner circumference of the flange.

5. The continuous fiber reinforced composite material-metal material hybrid composite gear according to claim 4, characterized in that: The first sub-plate, the flange plate, and the third sub-plate are provided with corresponding through holes in sequence; The composite gear further comprises: a fastener engaged at the through hole, wherein the fastener is connected to the first sub-plate, the flange and the third sub-plate.

6. The continuous fiber reinforced composite material-metal material hybrid composite gear according to claim 5, characterized in that: The flange includes a plurality of triangular areas arranged in sequence along the circumferential direction, a through hole is provided on the midline of each triangular area, the top angle of each triangular area is arranged toward the hub and is rounded, and the sides of two adjacent triangular areas are connected by an arc transition.

7. The continuous fiber reinforced composite material-metal material hybrid composite gear according to any one of claims 1 to 6, characterized in that: Also includes: An adhesive layer is bonded between the gear ring and the web.

8. The continuous fiber reinforced composite material-metal material hybrid composite gear according to any one of claims 1 to 6, characterized in that: The center hole is a non-circular hole, the shape of the outer circumference of the hub is consistent with the shape of the inner circumference of the center hole, and the outer circumference of the hub is in contact with the inner circumference of the center hole.

9. A reduction transmission assembly, characterized in that: include: A casing, wherein an assembly cavity is defined in the casing, and an input shaft hole and an output shaft hole are provided on the casing; An input gear, the input gear being assembled at the input shaft hole; An output gear, the output gear is assembled at the output shaft hole, and the output gear is meshed with the input gear in the assembly cavity; Wherein, at least one of the input gear and the output gear is a composite gear of continuous fiber reinforced composite material-metal material hybrid according to any one of claims 1-8.

10. An aircraft, characterized in that: include: Powertrain; A reduction transmission assembly, wherein the reduction transmission assembly is the reduction transmission assembly according to claim 9, wherein the input gear is connected to the power system; A rotor system is connected to the output gear.

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