Curved rim webless bevel gear

Abstract

This invention discloses a curved rim spokeless bevel gear, belonging to the field of gear transmission technology. The curved rim spokeless bevel gear of this invention includes a hub, a gear rack circumferentially disposed at one end of the hub, a first arc-shaped concave surface annularly disposed on the outer surface of the hub, a second arc-shaped concave surface connected below the first arc-shaped concave surface, a first arc-shaped convex surface connected below the second arc-shaped concave surface, a horizontal surface connected to the first arc-shaped convex surface, a third arc-shaped concave surface connected to the horizontal surface, and a first vertical surface connected below the third arc-shaped concave surface. The curved rim spokeless bevel gear of this invention can reduce the overall weight of the bevel gear while meeting deformation stress requirements, thereby improving the overall performance of the helicopter, while also saving materials and reducing costs.

Description

Technical Field

[0001] This application belongs to the field of gear transmission technology, and specifically relates to a curved rim bevel gear without spokes. Background Technology

[0002] Gear transmission has advantages such as high transmission efficiency, strong load-bearing capacity, long service life and compact structure. Therefore, it is widely used in the power transmission system of aero-engines. Aero-engine gears often operate under high speed and high load conditions, which leads to greater stress, more severe deformation and vibration during the service process. Therefore, there are extremely high requirements for the transmission performance of gears. The structure of the gears needs to be optimized to meet the requirements of strength and transmission characteristics, and to achieve the weight reduction of gears. Summary of the Invention

[0003] The purpose of this invention is to provide a curved rim bevel gear without spokes to solve the technical problem in the prior art that gears cannot simultaneously take into account deformation stress and lightweight design during transmission.

[0004] To achieve the above objectives, one embodiment of the present invention provides a curved rim spokeless bevel gear, including a hub, a gear rack disposed circumferentially at one end of the hub, a first arc-shaped concave surface disposed annularly on the outer surface of the hub, a second arc-shaped concave surface connected below the first arc-shaped concave surface, a first arc-shaped convex surface connected below the second arc-shaped concave surface, a horizontal surface connected to the first arc-shaped convex surface, a third arc-shaped concave surface connected to the horizontal surface, and a first vertical surface connected below the third arc-shaped concave surface.

[0005] In one preferred embodiment of the present invention, the wheel hub is a hollow wheel hub.

[0006] In one preferred embodiment of the present invention, the hub has a large opening at one end and a small opening at the other end, with the gear rack positioned at the end with the large opening.

[0007] In one preferred embodiment of the present invention, a second vertical surface is provided annularly on the inner surface of the hub, a fourth arc-shaped concave surface is connected below the second vertical surface, a second arc-shaped convex surface is connected below the fourth arc-shaped concave surface, and a third vertical surface is connected below the second arc-shaped convex surface.

[0008] In one preferred embodiment of the present invention, the connection between the second vertical surface and the fourth arc-shaped concave surface, the connection between the fourth arc-shaped concave surface and the second arc-shaped convex surface, and the connection between the second arc-shaped convex surface and the third vertical surface are all rounded.

[0009] In one preferred embodiment of the present invention, the second arc-shaped convex surface is more convex than the third vertical surface.

[0010] In one preferred embodiment of the present invention, the length of the third vertical plane is greater than that of the second vertical plane.

[0011] In one preferred embodiment of the present invention, the connection points of the first arc-shaped concave surface and the second arc-shaped concave surface, the connection points of the second arc-shaped concave surface and the first arc-shaped convex surface, the connection points of the first arc-shaped convex surface and the horizontal surface, the connection points of the horizontal surface and the third arc-shaped concave surface, and the connection points of the third arc-shaped concave surface and the first vertical surface are all rounded.

[0012] In one preferred embodiment of the present invention, the third arc-shaped concave surface is concave compared to the first vertical surface.

[0013] In one preferred embodiment of the present invention, the rim thickness of the wheel hub first increases and then decreases along the axial direction.

[0014] Compared with the prior art, this application has the following advantages: This invention relates to a curved-rim, spokeless bevel gear, comprising a hub with a gear rack circumferentially arranged at one end. The hub is divided into inner and outer parts. The outer surface of the hub has a first arc-shaped concave surface annularly arranged. A second arc-shaped concave surface is connected below the first arc-shaped concave surface, and a first arc-shaped convex surface is connected below the second arc-shaped concave surface. The first arc-shaped convex surface is connected to a horizontal plane, and the horizontal plane is connected to a third arc-shaped concave surface. A first vertical plane is connected below the third arc-shaped concave surface. This type of bevel gear can reduce the overall weight of the bevel gear while meeting deformation stress requirements, thereby improving the overall performance of the helicopter, while also saving materials and reducing costs.

[0015] Other features and advantages of this application will be set forth in the following description and will be apparent in part from the description or may be learned by practicing the application. The objectives and other advantages of this application may be realized and obtained by means of the structures pointed out in the description and the accompanying drawings. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure of a curved rim bevel gear without spokes in one embodiment of the present invention; Figure 2 This is a cross-sectional view of a bevel gear with curved rim and no spokes in one embodiment of the present invention; Figure 3 This is a dimensional diagram showing the cross-sectional dimensions of a bevel gear with curved rim and no spokes, according to one embodiment of the present invention. Figure 4 This is a schematic diagram of the equivalent stress calculation results of a curved rim bevel gear without spokes in one embodiment of the present invention; Figure 5 This is a schematic diagram of the improved front bevel gear in an embodiment of the present invention.

[0018] Wherein, ①-first arc-shaped concave surface, ②-second arc-shaped concave surface, ③-first arc-shaped convex surface, ④-horizontal surface, ⑤-third arc-shaped concave surface, ⑥-first vertical surface, ⑦-second vertical surface, ⑧-fourth arc-shaped concave surface, ⑨-second arc-shaped convex surface, ⑩-third vertical surface. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] The endpoints and any values ​​of the ranges disclosed in this invention are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this invention.

[0021] This invention discloses a curved rim, spokeless bevel gear, such as... Figure 1 , Figure 2 As shown, the device includes a hub, with a gear rack arranged circumferentially at one end of the hub. The outer surface of the hub is provided with a first arc-shaped concave surface ①, a second arc-shaped concave surface ② connected below the first arc-shaped concave surface ①, a first arc-shaped convex surface ③ connected below the second arc-shaped concave surface ②, a horizontal surface ④ connected to the first arc-shaped convex surface ③, a third arc-shaped concave surface ⑤ connected to the horizontal surface ④, and a first vertical surface ⑥ connected below the third arc-shaped concave surface ⑤. Preferably, the hub is a hollow hub.

[0022] The connections between the first concave surface ① and the second concave surface ②, the second concave surface ② and the first convex surface ③, the first convex surface ③ and the horizontal surface ④, the horizontal surface ④ and the third concave surface ⑤, and the third concave surface ⑤ and the first vertical surface ⑥ are all rounded. The purpose of rounding is to make the connections between the surfaces smooth. Preferably, the third concave surface ⑤ is more concave than the first vertical surface ⑥. The larger concavity can avoid protrusions or adjacent parts on the inner side of the rim, while forming an oil reservoir to facilitate lubrication; it also reduces the rigidity of this part, making the rim deformation more uniform. Furthermore, the rim thickness of the hub first thickens and then thins along the axial direction, making it thicker near the hub and gradually thinning towards the outside, while maintaining sufficient thickness in key stress areas. The gradual thickness can reduce weight while ensuring strength, optimize the moment of inertia, and make the stress distribution more balanced, avoiding abrupt changes in the cross-section. Furthermore, the hub has a large opening at one end and a small opening at the other end, with the gear rack positioned at the end with the large opening.

[0023] The inner surface of the hub is annularly provided with a second vertical surface ⑦. Below the second vertical surface ⑦ is a fourth arc-shaped concave surface ⑧. Below the fourth arc-shaped concave surface ⑧ is a second arc-shaped convex surface ⑨. Below the second arc-shaped convex surface ⑨ is a third vertical surface ⑩. The connections between the second vertical surface ⑦ and the fourth arc-shaped concave surface ⑧, the connections between the fourth arc-shaped concave surface ⑧ and the second arc-shaped convex surface ⑨, and the connections between the second arc-shaped convex surface ⑨ and the third vertical surface ⑩ are all rounded. The purpose of the rounded corners is to ensure a smooth transition at the connections of each surface. Preferably, the second arc-shaped convex surface ⑨ protrudes outward compared to the third vertical surface ⑩. This outward protrusion structure improves the connection rigidity between the hub and the shaft, preventing relative slippage. Furthermore, the length of the third vertical surface ⑩ is greater than that of the second vertical surface ⑦. The longer third vertical surface ⑩, as the main mating section, increases the contact length with the shaft, improving load-bearing capacity and alignment. The shorter second vertical surface ⑦ is used for end guidance, reducing ineffective friction.

[0024] The curved rim spokeless bevel gear forms a hierarchical structure through multiple arc-shaped convex surfaces, arc-shaped concave surfaces, horizontal surfaces, and vertical surfaces. The rim surface is smooth, the outer contour lines are smooth, and the overall shape is wider at the top and narrower at the bottom. The outer contour transition part adopts a circular arc structure, and the middle section of the inner contour is connected by a circular arc, resulting in a smooth and natural overall structure.

[0025] The curved rim spokeless bevel gear of the present invention is suitable for high-speed, high-load aero-engine transmission systems, taking into account both lightweight and high rigidity.

[0026] The curved rim bevel gear of the present invention, under the following conditions: the tangential component of the meshing force on the teeth is less than or equal to 1200 N, the axial component of the meshing force is less than or equal to 400 N, the radial component of the meshing force is less than or equal to 700 N, and the bevel gear speed is less than or equal to 30000 rpm, provided that the total mass of the teeth does not exceed 0.05 kg, and the yield strength of the rim material is not less than 960 MPa and the material density is not greater than 7.86 g / cm³, can achieve the following performance: 3 Curved rim, spokeless bevel gear, like Figure 3 As shown, it includes the following parameters: The radius of the first concave arc surface ① is R0=4.0mm, the radius of the second concave arc surface ② is R1=5.2mm, the radius of the first convex arc surface ③ is R2=4.2mm, the length of the horizontal surface ④ is L1=1.3mm, the radius of the third concave arc surface ⑤ is R3=2.0mm, the length of the first vertical surface ⑥ is H1=9.7mm, the length of the second vertical surface ⑦ is H2=8.0mm, the radius of the fourth concave arc surface ⑧ is R4=9.6mm, the radius of the second convex arc surface ⑨ is R5=3.4mm, the length of the third vertical surface ⑩ is H3=11.2mm, the distance from the second vertical surface ⑦ to the center of the hub is L2=37.7mm, the distance from the third vertical surface ⑩ to the center of the hub is L3=31.7mm, and the distance from the fourth vertical surface to the center of the hub is L4=36.2mm.

[0027] Finite element simulation analysis was performed on the structure with a mesh element size of 2 mm and a mesh element count of 54771. The calculated equivalent stress (von Mises stress) contour plot is shown below. Figure 4 As shown, the mass is 0.3014 kg. Analysis revealed a maximum von Mises stress of 758 MPa, compared to the original bevel gear (e.g., ...). Figure 5 As shown, the mass is approximately 0.4335 kg. In this embodiment, the mass of the curved rim bevel gear without spokes is reduced by 30.47% when the stress is less than the material yield strength, thereby improving the overall performance of the helicopter and saving materials and reducing costs.

[0028] The curved rim, spokeless bevel gear of this invention has a main gear profile divided into inner and outer parts. The outer profile consists of four circular arcs and two straight lines connecting the arcs. The inner profile consists of two straight lines parallel to the axis, two arcs, and multiple rounded corners. The radii of the different straight lines within the inner profile vary, and the main body of the inner profile is wider at the top and narrower at the bottom. This type of bevel gear can reduce the overall weight of the bevel gear while meeting deformation stress requirements, thereby improving the overall performance of the helicopter, while also saving materials and reducing costs.

[0029] Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A curve-rimmed, webless bevel gear characterized by: The device includes a hub, one end of which is provided with a gear rack along the circumference. The outer surface of the hub is provided with a first arc-shaped concave surface in an annular shape. A second arc-shaped concave surface is connected below the first arc-shaped concave surface. A first arc-shaped convex surface is connected below the second arc-shaped concave surface. The first arc-shaped convex surface is connected to a horizontal surface. The horizontal surface is connected to a third arc-shaped concave surface. A first vertical surface is connected below the third arc-shaped concave surface.

2. A curve bevel gear without web of curve rim as claimed in claim 1, characterized in that: The wheel hub is a hollow wheel hub.

3. A curve bevel gear without web of curve bevel gear as claimed in claim 2, characterized in that: The hub has a large opening at one end and a small opening at the other end, with the gear rack positioned at the end with the large opening.

4. A curve bevel gear without spokes as claimed in claim 2, characterized in that: The inner surface of the hub is provided with a second vertical surface in an annular shape. A fourth arc-shaped concave surface is connected below the second vertical surface. A second arc-shaped convex surface is connected below the fourth arc-shaped concave surface. A third vertical surface is connected below the second arc-shaped convex surface.

5. A curve bevel gear without spokes as claimed in claim 4, characterized in that: The junctions between the second vertical surface and the fourth concave surface, the junctions between the fourth concave surface and the second convex surface, and the junctions between the second convex surface and the third vertical surface are all rounded.

6. A curve bevel gear without spokes as claimed in claim 4, characterized in that: The second arc-shaped convex surface is more convex than the third vertical surface.

7. A bevel gear with curved rim and no spokes as described in claim 4, characterized in that: The length of the third vertical plane is greater than that of the second vertical plane.

8. A curve bevel gear without web of curve bevel gear as claimed in claim 1 characterized in that: The joints between the first and second arc-shaped concave surfaces, the joints between the second arc-shaped concave surface and the first arc-shaped convex surface, the joints between the first arc-shaped convex surface and the horizontal surface, the joints between the horizontal surface and the third arc-shaped concave surface, and the joints between the third arc-shaped concave surface and the first vertical surface are all rounded.

9. A bevel gear with curved rim and no spokes as described in claim 1, characterized in that: The third arc-shaped concave surface is more concave than the first vertical surface.

10. A curve bevel gear without web of curve bevel gear as claimed in claim 1 characterized in that: The rim thickness of the hub first increases and then decreases along the axial direction.

Images