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 an axis supporting part and a gear ring. The gear ring is connected to the axis supporting part, the gear ring and the axis supporting part 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. The axis supporting part is of a laminated plate structure integrally formed by continuous fiber reinforced composite materials in a mold pressing mode. According to the compound gear disclosed by the embodiment of the invention, the axis supporting part 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 composite gear of the first aspect of the present invention, the composite gear is used in an aircraft, and the composite gear comprises: an axial support portion and a gear ring. The gear ring is connected to the axial support portion, the gear ring is coaxially arranged with the axial support portion, the gear ring is provided with meshing teeth distributed at intervals along the circumferential direction, and the gear ring is a metal part.

[0007] The axial support part is a laminate structure formed by compression molding of continuous fiber reinforced composite materials, and the structure of the axial support part is as follows: The axial support portion includes multiple layers of carbon fiber prepregs sequentially distributed along the axial direction of the axial support portion, 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, molding and curing are performed; 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 carbon fiber prepreg has at least 30 layers, the axial support portion is a tube with a wall thickness of at least 6 mm, and the ratio of the axial length to the outer diameter of the axial support portion is in the range of 5 to 15; The obtained torsional strength of the axial support portion ranges from 100MPa to 150MPa, and the bending strength ranges from 170MPa to 220MPa.

[0008] According to the composite gear of the embodiment of the present invention, the axial support part is a laminate structure formed by continuous fiber reinforced composite material compression molding, which achieves the goal of lightweight composite gear. 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 some embodiments of the composite gear of the present invention, the axial support portion includes: a first support shaft, the outer circumferential surface of the first support shaft includes an outer contact circumferential surface; the meshing teeth are formed on the outer circumferential surface of the ring gear, and the inner circumferential surface of the ring gear includes an inner contact circumferential surface; the outer contact circumferential surface and the inner contact circumferential surface are both non-cylindrical surfaces, the inner contact circumferential surface is consistent in shape with the outer contact circumferential surface, and the ring gear outer sleeve is connected to the outer contact circumferential surface of the first support shaft.

[0010] According to some embodiments of the composite gear of the present invention, the axial support portion includes: a web, one side surface of the web in the thickness direction includes a first contact annular surface; the gear ring forms the meshing teeth at one axial end and forms a second contact annular surface at the other axial end; the gear ring is connected to one axial side of the web, and the first contact annular surface is in contact and connected with the second contact annular surface.

[0011] According to some embodiments of the composite gear of the present invention, the axial support portion further comprises: a second support shaft, the second support shaft is disposed at the center of the web, and the second support shaft and the web are integrally formed by continuous fiber reinforced composite material compression molding.

[0012] In some optional embodiments, the composite gear further comprises: a plurality of fasteners connected between the web and the gear ring.

[0013] In some optional embodiments, the first contact annular surface is a plane or a curved surface.

[0014] According to some embodiments of the present invention, the composite gear further includes: an adhesive layer, wherein the adhesive layer is bonded between the gear ring and the axial support portion.

[0015] In some optional embodiments, the thickness of the adhesive layer is 0.1 mm-0.2 mm.

[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 It is a schematic diagram of the structure of a composite gear in 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 diagrams of the structures of compound gears in other embodiments of the present invention; Figure 4 Exploded diagrams of compound gears according to other embodiments of the present invention; Figure 5 Schematic diagrams of the connection between the gear ring and the web in other embodiments of the present invention; Figure 6 for Figure 5 Sectional view at AA in the middle; Figure 7 A schematic structural diagram of a casing in some embodiments of the present invention; Figure 8 An exploded view of a casing according to some embodiments of the present invention; Fig. 9 It is a schematic diagram of the structure of a reduction transmission assembly in some embodiments of the present invention; Fig.10 Schematic diagram of the internal structure of a reduction transmission assembly according to some embodiments of the present invention; Fig.11 A schematic diagram of the structure of an aircraft according to some embodiments of the present invention; Fig.12 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.13 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; The axial support portion 10, the first support shaft 11, the outer contact peripheral surface 110, the second support shaft 12, the web 13, and the first contact annular surface 131; Gear ring 40, meshing teeth 41, inner contact circumferential surface 42, second contact annular surface 43, fastener 50, adhesive layer 60; 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 - Figure 6 A composite gear 100 according to an embodiment of a first aspect of the present invention will be described.

[0024] According to the composite gear 100 of the first embodiment of the present invention, the application field of the composite gear 100 is not limited, and it can be used in a variety of equipment and machinery that require gear transmission, such as in the transmission device of the aircraft 10000. For the convenience of description, the composite gear 100 is used in the transmission device of the aircraft 10000 for illustration in this application.

[0025] like Figure 1 - Figure 2 As shown, the composite gear 100 according to the first embodiment of the present invention includes: an axial support portion 10 and a ring gear 40 .

[0026] The axial support portion 10 is a continuous fiber reinforced composite material component.

[0027] The use of continuous fiber reinforced composite material as the axial support portion 10 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 rigidity (ie, rigidity / weight ratio), which enables the axial support portion 10 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 device of the 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 axial support part 10, reduce the probability of its corrosion, and correspondingly extend the service life of the composite gear 100 and reduce maintenance costs.

[0031] The gear ring 40 is connected to the axial support part 10 . The gear ring 40 is coaxially arranged with the axial support part 10 . The gear ring 40 is provided with meshing teeth 41 distributed at intervals along the circumferential direction. The gear ring 40 is a metal part.

[0032] It can be known that the axes of the ring gear 40 and the axial support part 10 coincide with each other, which can ensure the accuracy and stability of 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 power and torque can be transmitted through the meshing teeth 41 .

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

[0035] Optionally, the connection method between the gear ring 40 and the shaft support portion 10 can be one or a combination of welding, bolt connection or adhesive connection. For example, in some solutions, the gear ring 40 and the shaft support portion 10 are connected by bolts. Or in some other solutions, the gear ring 40 and the shaft support portion 10 are connected by a combination of bolt connection and adhesive connection.

[0036] The axial support portion 10 is a laminate structure formed by compression molding of continuous fiber reinforced composite materials.

[0037] In the present application, the axial support portion 10 includes multiple layers of carbon fiber prepregs sequentially distributed along the axial direction of the axial support portion 10. 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 and curing are performed.

[0038] In some specific embodiments, 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 Material 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 epoxy resin structural adhesive film ranges from 0.127mm to 0.254mm, and the shear strength ranges from 30MPa to 40MPa.

[0043] The carbon fiber prepreg fabric has at least 30 layers, the axial support portion 10 is a tube with a wall thickness of at least 6 mm, and the ratio of the axial length to the outer diameter of the axial support portion 10 is in the range of 5-15.

[0044] The obtained axial support portion 10 has a torsional strength ranging from 100 MPa to 150 MPa, and a bending strength ranging from 170 MPa to 220 MPa.

[0045] To further facilitate understanding of the structure of the axial support portion 10 of the present application, the axial support portion 10 of some embodiments of the present application can be formed by compression molding after all the materials are laid up, and the process shown in Table 1 below can be selected: Table 1

[0046] 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.

[0047] 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.

[0048] In this way, the axial support portion 10 required by the present application can be obtained.

[0049] According to some embodiments of the present invention, the composite gear 100 is Figure 1 - Figure 2As shown, the axial support part 10 includes: a first support shaft 11. The outer peripheral surface of the first support shaft 11 includes an outer contact peripheral surface 110; the outer peripheral surface of the gear ring 40 is formed with meshing teeth 41, and the inner peripheral surface of the gear ring 40 includes an inner contact peripheral surface 42; the outer contact peripheral surface 110 and the inner contact peripheral surface 42 are both non-cylindrical surfaces, and the inner contact peripheral surface 42 is consistent with the outer contact peripheral surface 110, and the outer sleeve of the gear ring 40 is connected to the outer contact peripheral surface 110 of the first support shaft 11.

[0050] In the above technical solution, the first support shaft 11 is a component of the composite gear 100 and can provide light and strong support.

[0051] The outer circumferential surface of the gear ring 40 is provided with meshing teeth 41 spaced apart along the circumferential direction, and these teeth are used to mesh with other gears or transmission components to achieve torque transmission.

[0052] The outer circumference of the first support shaft 11 includes a non-cylindrical outer contact surface 110, the inner circumference of the gear ring 40 is constructed as a non-cylindrical surface, and the shape of the inner contact surface 42 matches the outer contact surface 110 of the first support shaft 11 to ensure a tight fit between the two.

[0053] When both the outer contact surface 110 and the inner contact surface 42 are non-cylindrical surfaces, and the outer sleeve of the gear ring 40 is connected to the outer contact surface 110 of the first support shaft 11, it means that they are not simple circular cross-sections, but surfaces with specific geometric shapes. For example, the cross-sectional shape of such non-cylindrical surface can be polygonal, elliptical or other non-standard geometric shapes.

[0054] The non-cylindrical surface design can effectively prevent the relative rotation or positional displacement between the axial support part 10 and the gear ring 40. This non-cylindrical surface design makes the fit between the two parts tighter and reduces the relative sliding caused by rotation or vibration. At the same time, the profile of the non-cylindrical surface also has a certain self-locking function, which can ensure a stable and reliable connection between the two even under harsh conditions of high torque.

[0055] In some embodiments, the cross-sectional shapes of the outer contact surface 110 and the inner contact surface 42 are centrally symmetrical figures, such as a quadrilateral, a hexagon, an octagon or other polygons.

[0056] This is because the central symmetric pattern, as the cross-sectional shape of the outer contact circumferential surface 110 and the inner contact circumferential surface 42, can make the two contact surfaces have a relatively 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.

[0057] Since the stress distribution is more uniform, the design of the central symmetric pattern can improve the connection strength between the shaft support portion 10 and the gear ring 40. This uniform stress distribution reduces material fatigue caused by stress concentration, thereby extending the service life of the composite gear 100.

[0058] In addition, the uniform stress distribution helps to reduce vibration and noise caused by unbalanced forces, thereby helping to improve the smoothness of operation of the aircraft 10000 transmission device.

[0059] According to some embodiments of the present invention, the composite gear 100 is Figure 3 - Figure 4 As shown, the axial support portion 10 includes: a web 13. One side surface of the web 13 in the thickness direction includes a first contact annular surface 131; the gear ring 40 forms meshing teeth 41 at one end in the axial direction, and forms a second contact annular surface 43 at the other end in the axial direction; the gear ring 40 is connected to one side of the web 13 in the axial direction, and the first contact annular surface 131 is in contact and connected with the second contact annular surface 43.

[0060] The web 13 is a part of the shaft support portion 10 of the composite gear 100 and is used to provide structural support and a path for torque transmission.

[0061] A first contact annular surface 131 is provided on one side surface in the thickness direction of the web 13. The first contact annular surface 131 is in contact with one end of the gear ring 40 to ensure a tight connection between the two. Here, the thickness direction of the web 13 is parallel to the axial direction of the gear ring.

[0062] The gear ring 40 has meshing teeth 41 at one axial end, and the meshing teeth 41 are used to mesh with other gears or transmission components to achieve torque transmission.

[0063] A second contact annular surface 43 is formed at the other axial end of the gear ring 40, and the second contact annular surface 43 matches the first contact annular surface 131 on the web 13 of the axial support portion 10 to form a contact connection. The position of the second contact annular surface 43 enables it to correspond to the first contact annular surface 131, thereby ensuring a tight fit between the two.

[0064] Optionally, the first contact annular surface 131 and the second contact annular surface 43 may be connected by one or more of welding, riveting, screwing or gluing. Alternatively, the first contact annular surface 131 and the second contact annular surface 43 may be connected by a connection method in the prior art, and the contact connection between the first contact annular surface 131 and the second contact annular surface 43 is not limited in the present application.

[0065] In the above technical solution, the second contact annular surface 43 is not only used for support, but also can transmit the force on the meshing teeth 41 to the first contact annular surface 131 to a certain extent. In this way, the force on the ring gear 40 can be effectively transmitted to the web 13, and then further transmitted to the entire gear system by the web 13. This design enables the web 13 to better disperse local stress, improve the efficiency and reliability of torque transmission, and extend the service life of the composite gear 100.

[0066] The composite gear 100 configured in this way, on the one hand, utilizes the continuous fiber reinforced composite material to achieve the goal of lightweight, and on the other hand, by providing the web 13 and supporting and strengthening the ring gear 40 with the help of the web 13, the service strength of the composite gear 100 is improved.

[0067] According to some embodiments of the present invention, the composite gear 100 is Figure 3 - Figure 4 As shown, the axial support portion 10 further includes: a second support shaft 12, which is disposed at the center of the web 13, and the second support shaft 12 and the web 13 are integrally formed by compression molding of a continuous fiber reinforced composite material.

[0068] The second support shaft 12 is located at the center of the web 13, which can further enhance the structural strength and rigidity of the axial support portion 10 and ensure stability when subjected to high torque.

[0069] The second support shaft 12 and the web 13 are integrally formed by compression molding of continuous fiber reinforced composite materials. This means that during the manufacturing process, the second support shaft 12 and the web 13 are formed as a whole by compression molding technology, rather than being connected later. The advantage of compression molding is that it can ensure that the connection between the second support shaft 12 and the web 13 is very strong, without obvious interfaces or seams, thereby avoiding potential weak points caused by seams or interfaces.

[0070] The overall structural strength of the axial support portion 10 is enhanced by the integrally formed second support shaft 12 and web 13. The combination of web 13 and second support shaft 12 can better resist external loads, especially high torque loads, and ensure reliability and stability under some complex working conditions.

[0071] Furthermore, the second support shaft 12 and the web 13 are integrally formed by molding, which simplifies the production process to a certain extent, reduces the assembly steps, thereby reducing production costs and improving production efficiency. At the same time, the integral molding can reduce or even avoid assembly errors, ensuring the high quality and consistency of the composite gear 100.

[0072] The second support shaft 12 and the web 13 use continuous fiber reinforced composite materials, which not only helps to achieve the goal of lightweight, but also helps to maintain the high strength of the composite gear 100 structure, so that the entire axial support part 10 is both light and strong, and is suitable for use in aircraft 10000 that have strict requirements on weight and strength.

[0073] In some optional embodiments, combined with Figure 3 - Figure 4 The composite gear 100 further includes: a plurality of fasteners 50 , wherein the plurality of fasteners 50 are connected between the web 13 and the ring gear 40 .

[0074] These fasteners 50 are used to ensure a firm connection between the web 13 and the gear ring 40 to prevent relative displacement or loosening during high torque transmission.

[0075] Optionally, the fastener 50 may be a rivet, or other types of connecting parts, such as a screw, a pin, etc.

[0076] 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.

[0077] In some optional embodiments, the plurality of fasteners 50 are distributed along the circumferential direction with the shaft 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 shaft 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.

[0078] 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.

[0079] 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.

[0080] Optionally, the number of fasteners 50 is not specifically limited and can be further adjusted according to user needs.

[0081] In some optional embodiments, such as Figure 5 - Figure 6 As shown, the first contact annular surface 131 is a plane or a curved surface.

[0082] Optionally, the first contact annular surface 131 is a plane or a curved surface, and the second contact annular surface 43 is configured as a structure suitable for contacting the first contact annular surface 131 .

[0083] In some technical solutions, the first contact annular surface 131 is a plane, and the second contact annular surface 43 is also constructed as a plane, so as to ensure that the two contact surfaces are in flat contact.

[0084] In some other technical solutions, the first contact annular surface 131 is a curved surface, and the second contact annular surface 43 is also constructed as a matching curved surface to increase the contact area.

[0085] First, the curved surface design can ensure that the contact between the web 13 and the gear ring 40 is more uniform, thereby making the pressure distribution on the contact surface more uniform, avoiding material fatigue or damage caused by excessive local pressure. Second, the curved surface design can improve the synchronous rotation performance between the web 13 and the gear ring 40. When the two curved contact surfaces are tightly fitted, the relative sliding or displacement caused by rotation can be reduced, ensuring the accuracy and stability of the synchronous rotation between the web 13 and the gear ring 40, thereby reducing the friction and wear caused by rotation and extending the service life of the composite gear 100.

[0086] In some optional embodiments, the curved surface may be a convex surface, a concave surface, or a combination of convex and concave surfaces.

[0087] According to some embodiments of the present invention, the composite gear 100 further includes an adhesive layer 60 , wherein the adhesive layer 60 is bonded between the ring gear 40 and the shaft support portion 10 .

[0088] The adhesive layer 60 is located between the gear ring 40 and the shaft support portion 10. The adhesive layer 60 serves to firmly bond the two components together.

[0089] On the one hand, by adding the adhesive layer 60, the connection strength between the ring gear 40 and the axial support portion 10 is enhanced to a certain extent. The adhesive can fill in tiny gaps 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 relative displacement or looseness between the ring gear 40 and the axial support portion 10, thereby improving the connection strength between the two.

[0090] 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.

[0091] 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.

[0092] In some optional embodiments, the thickness of the adhesive layer 60 is 0.1 mm-0.2 mm.

[0093] 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 to be 0.1 mm-0.2 mm, which can provide sufficient bonding strength to ensure the tight bonding between the ring gear 40 and the shaft support part 10, 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.

[0094] 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. Figure 7 - Fig. 9 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.10 , 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.

[0095] 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.

[0096] 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.

[0097] 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.

[0098] 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.

[0099] 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.

[0100] 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 ring gear 40, which can provide higher hardness and wear resistance, ensuring the reliability of the composite gear 100 when transmitting high torque. Therefore, by combining the lightweight design with the 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.

[0101] 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.

[0102] 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 .

[0103] like Fig.11 - Fig.13 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.

[0104] 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.12 , 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.

[0105] The rotor system 3000 is connected to the output gear 400 and is responsible for transmitting the decelerated power to the rotor blades. Fig.13 , 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.

[0106] 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.

[0107] 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.

[0108] Reference below Figure 1 - Figure 6 The composite gear 100 according to the embodiment of the present invention is described in detail with reference to a specific embodiment. It should be understood that the following description is only for exemplary purposes and is not intended to limit the invention.

[0109] Example 1 Reference Figure 1 The composite gear 100 includes an axial support portion 10 and a ring gear 40 .

[0110] Reference Figure 2 The gear ring 40 is connected to the axial support part 10, and the gear ring 40 is coaxially arranged with the axial support part 10. The gear ring 40 is provided with meshing teeth 41 distributed at intervals along the circumferential direction, and the gear ring 40 is a metal part.

[0111] The axial support part 10 is a laminate structure formed by continuous fiber reinforced composite material compression molding. The axial support part 10 includes multiple layers of carbon fiber prepreg distributed in sequence along the axial direction of the axial support part 10. Each layer of carbon fiber prepreg is a T700-3K plain weave reinforced fiber layer. 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. The ply design structure of the axial support part 10 is shown in Table 2.

[0112] Table 2 Layer design in the axial support portion 10 of the present invention

[0113] 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 and a shear strength of 40 MPa.

[0114] In Example 1, the processing method of the axial support portion 10 is carried out according to the process in Table 1 above.

[0115] The structural parameters of the axial support portion 10 are: the torsional strength ranges from 100 MPa to 150 MPa, and the bending strength ranges from 170 MPa to 220 MPa.

[0116] Reference Figure 2 The axial support portion 10 includes: a first support shaft 11. The outer peripheral surface of the first support shaft 11 includes: an outer contact peripheral surface 110.

[0117] The outer circumferential surface of the ring gear 40 is formed with meshing teeth 41 , and the inner circumferential surface of the ring gear 40 includes an inner contact circumferential surface 42 .

[0118] The outer contact circumferential surface 110 and the inner contact circumferential surface 42 are both non-cylindrical surfaces. The inner contact circumferential surface 42 has the same shape as the outer contact circumferential surface 110 . The gear ring 40 is connected to the outer contact circumferential surface 110 of the first support shaft 11 through an outer sleeve.

[0119] Example 2 Reference Figure 3 The composite gear 100 includes an axial support portion 10 and a ring gear 40 .

[0120] The axial support portion 10 is a continuous fiber reinforced composite material component.

[0121] The gear ring 40 is connected to the axial support part 10 . The gear ring 40 is coaxially arranged with the axial support part 10 . The gear ring 40 is provided with meshing teeth 41 distributed at intervals along the circumferential direction. The gear ring 40 is a metal part.

[0122] The structure of the axial support portion 10 in the second embodiment is the same as the structure of the axial support portion 10 in the first embodiment.

[0123] Reference Figure 3 - Figure 4 The axial support portion 10 includes: a second support shaft 12 and a web 13 .

[0124] One side surface of the web 13 in the thickness direction includes a first contact annular surface 131 .

[0125] Reference Figure 5 The gear ring 40 has meshing teeth 41 formed at one end in the axial direction and a second contact annular surface 43 formed at the other end in the axial direction.

[0126] The gear ring 40 is connected to one axial side of the web 13 , and the first contact annular surface 131 is in contact with and connected to the second contact annular surface 43 .

[0127] The first contact annular surface 131 and the second contact annular surface 43 are both curved surfaces.

[0128] The second support shaft 12 is arranged at the center of the web 13 , and the second support shaft 12 and the web 13 are integrally formed by compression molding of a continuous fiber reinforced composite material.

[0129] A plurality of fasteners 50 are connected between the web 13 and the ring gear 40 .

[0130] The adhesive layer 60 is bonded between the gear ring 40 and the axial support portion 10. The thickness of the adhesive layer 60 is 0.1 mm to 0.2 mm.

[0131] Comparative Example 1 The structure and parameters of the composite gear in comparative example 1 are substantially the same as those of the composite gear 100 in embodiment 1, except that the ply design structure of the axial support portion in the comparative example is as shown in Table 3.

[0132] Table 3 Layer design of the axial support part in comparative example 1

[0133] 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 embodiment 1, except that the ply design structure of the axial support portion in the comparative example is as shown in Table 4.

[0134] Table 4 Layer design of the axial support part in comparative example 2

[0135] Performance Testing 1. Performance testing methods.

[0136] (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.

[0137] 2. Performance test results

[0138] (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.

[0139] 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.

[0140] 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.

[0141] 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, characterized in that: The composite gear is used in an aircraft, and the composite gear comprises: Axis support portion; A gear ring, the gear ring is connected to the axial support portion, the gear ring is coaxially arranged with the axial support portion, the gear ring is provided with meshing teeth distributed at intervals along the circumferential direction, and the gear ring is a metal part; The axial support part is a laminate structure formed by compression molding of continuous fiber reinforced composite materials, specifically: The axial support portion includes multiple layers of carbon fiber prepregs sequentially distributed along the axial direction of the axial support portion, 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, molding and curing are performed; 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 carbon fiber prepreg has at least 30 layers, the axial support portion is a tube with a wall thickness of at least 6 mm, and the ratio of the axial length to the outer diameter of the axial support portion is in the range of 5 to 15; The obtained torsional strength of the axial support portion ranges from 100MPa to 150MPa, and the bending strength ranges from 170MPa to 220MPa.

2. The composite gear according to claim 1, characterized in that: The axial support portion includes: a first support shaft, the outer peripheral surface of the first support shaft includes an outer contact peripheral surface; The meshing teeth are formed on the outer circumferential surface of the gear ring, and the inner circumferential surface of the gear ring includes an inner contact circumferential surface; The outer contact circumferential surface and the inner contact circumferential surface are both non-cylindrical surfaces, the inner contact circumferential surface is consistent in shape with the outer contact circumferential surface, and the gear ring sleeve is connected to the outer contact circumferential surface of the first support shaft.

3. The composite gear according to claim 1, characterized in that: The axial support portion comprises: a web, a surface on one side in the thickness direction of the web comprising a first contact annular surface; The gear ring is formed with the meshing teeth at one end in the axial direction and a second contact annular surface at the other end in the axial direction; The gear ring is connected to one axial side of the web, and the first contact annular surface is in contact with and connected to the second contact annular surface.

4. The composite gear according to claim 3, characterized in that: The axial support portion further includes: a second support shaft, the second support shaft is arranged at the center of the web, and the second support shaft and the web are integrally formed by continuous fiber reinforced composite material compression molding.

5. The composite gear according to claim 3, characterized in that: Also includes: A plurality of fasteners are connected between the web and the ring gear.

6. The composite gear according to claim 3, characterized in that: The first contact annular surface is a plane or a curved surface.

7. The 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 axial support portion.

8. The composite gear according to claim 7, characterized in that: The thickness of the adhesive layer is 0.1 mm-0.2 mm.

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 compound gear 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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