Solar gear structure and gear box
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- NANJING NANGAOCHI NEW ENERGY AUTOMOBILE TRANSMISSION EQUIP CO LTD
- Filing Date
- 2025-07-01
- Publication Date
- 2026-07-07
Smart Images
Figure CN224469616U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of mechanical transmission technology, and more specifically, to a sun gear structure and a gearbox. Background Technology
[0002] The sun gear is a basic component of a planetary gear train. In a planetary gear system, the external gear that serves as the central gear is called the sun gear, which can also be called the sun gear. In the prior art, the sun gear is sleeved on the outside of the drive shaft and connected to the drive shaft using a spline structure. At the same time, the external teeth of the sun gear mesh with the planet gears mounted on the planet carrier.
[0003] The inventors discovered during their research that the existing sun gear technology has at least the following drawbacks:
[0004] 1. The sun gear uses a floating mechanism with an internal spline and an external spline on the drive shaft in a clearance fit to achieve load sharing among the meshing planetary gears. This load sharing process causes the spline to experience sliding friction and clearance impact within the clearance range, varying with the meshing frequency of the sun gear. As the rotational speed increases, the frequency of sliding friction and clearance impact on the clearance-fitted spline increases simultaneously. Furthermore, under the increased centrifugal force, the lubricating oil within the spline clearance leaks out more rapidly, increasing spline tooth surface wear and vibration impact. Especially during high-speed, heavy-load transmissions, conventional sun gear structures are simple and lack optimized structures for spline lubrication and noise reduction, making them highly susceptible to spline wear failure and vibration / impact noise.
[0005] 2. The lack of an optimized structure for sun gear transmission lubrication means that as the rotational speed increases, the lubricating oil adhering to the tooth surface will be lost more rapidly under the increased centrifugal force, affecting the reliability of tooth surface lubrication. Especially under high-speed, heavy-load transmission, the combined effect of rapidly lost lubricating oil and high stress on the tooth surface can easily cause the failure of the lubricating oil film on the tooth surface, exacerbating tooth surface wear, scuffing failure, and transmission noise. Utility Model Content
[0006] The purpose of this invention includes, for example, providing a sun gear structure and gearbox that can improve lubrication, reduce wear rate, reduce transmission noise, and extend service life.
[0007] The embodiments of this utility model can be implemented as follows:
[0008] In a first aspect, this utility model provides a sun gear structure, comprising:
[0009] The shaft body, multiple tooth bodies, and multiple internal splines are provided. The multiple tooth bodies are all fixed on the outer circumferential surface of the shaft body and are arranged at intervals in the circumferential direction of the shaft body.
[0010] The shaft is provided with an assembly through hole, which includes a first hole section and a second hole section that are connected. The plurality of internal splines are all fixed on the hole wall of the first hole section and are arranged at intervals in the circumferential direction of the shaft. The hole wall of the second hole section is provided with a first oil guide groove for guiding the lubricating medium toward the internal splines.
[0011] In an optional embodiment, the first oil guide groove is configured as a spiral groove extending in a spiral line around the axis of the shaft.
[0012] Based on the above scheme, the first oil guide groove extending in a spiral shape can not only continuously guide the lubricating medium to the position of the internal spline teeth under the rotation of the sun gear, but also make the lubricating medium evenly distributed in the circumferential direction of the shaft, so that multiple internal spline teeth can be fully lubricated, improve the lubrication effect, and reduce wear.
[0013] In an optional embodiment, the shaft has a first end face and a second end face disposed opposite to each other in its axial direction, and the two ends of the mounting through hole pass through the first end face and the second end face respectively; a first lubrication through groove is provided on the first end face, one end of the first lubrication through groove is connected to the first hole segment, and the other end of the first lubrication through groove extends to the outer peripheral surface of the shaft.
[0014] Based on the above solution, by setting a first lubrication groove on the first end face, the lubricating medium entering from the assembly through hole passes through the internal spline and lubricates the internal spline, and can then be discharged from the assembly through hole under the guidance of the first lubrication groove, thereby forming a stable flowing dynamic oil film on the first end face, enhancing the floating lubrication of the internal spline, reducing axial floating impact, and quickly dissipating the generated heat, avoiding oil accumulation and difficulty in heat dissipation, and improving operational stability and reliability.
[0015] In an optional embodiment, a second lubrication groove is provided on the second end face, one end of the second lubrication groove is connected to the first oil guide groove, and the other end of the second lubrication groove extends to the outer peripheral surface of the shaft.
[0016] Based on the above scheme, after the sun gear is assembled on the drive shaft, the second end face is close to the motor side. The second lubrication groove on the second end face can collect the lubricating medium that is directed out from the oil guide groove of the housing, which increases the probability of the lubricating medium entering the first oil guide groove. This allows more lubricating medium to enter the location of the internal spline teeth, improving the lubrication effect of the internal spline teeth. At the same time, it can also enhance the axial floating lubrication of the second end face and reduce the axial floating impact.
[0017] In an optional embodiment, there are multiple first lubrication channels and / or multiple second lubrication channels, with the multiple first lubrication channels arranged at intervals in the circumferential direction of the shaft body; and the multiple second lubrication channels arranged at intervals in the circumferential direction of the shaft body.
[0018] Based on the above scheme, there are multiple first and second lubrication channels, which are evenly distributed around the shaft. This increases the flow of lubricating medium and makes the lubricating medium more evenly distributed around the shaft, thereby improving the lubrication effect.
[0019] In an optional embodiment, the first lubrication channel and / or the second lubrication channel are configured as arc-shaped channels.
[0020] Based on the above solution, the arc-shaped through groove is easy to process, reduces stress concentration, is not prone to cracking, and has a long service life.
[0021] In an optional embodiment, the shaft includes a first shaft segment and a second shaft segment connected together, the plurality of teeth are all fixed to the first shaft segment, the plurality of teeth are arranged at intervals in the circumferential direction of the second shaft segment, and tooth grooves are formed between adjacent teeth;
[0022] The outer circumferential surface of the second shaft segment is provided with a plurality of second oil guide grooves, which are arranged at intervals in the circumferential direction of the second shaft segment. One end of each second oil guide groove is connected to the corresponding tooth groove, and the other end extends to the end face of the second shaft segment. The second oil guide groove is used to guide the lubricating medium into the corresponding tooth groove.
[0023] Based on the above scheme, during the rotation of the sun gear, the lubricating medium located on the outer side enters the second oil guide groove. Under the guidance of the second oil guide groove, the lubricating medium can enter the position of the tooth body evenly, and enhance the lubrication of the meshing tooth surface.
[0024] In an optional embodiment, the plurality of second oil guide grooves are arranged in a spiral.
[0025] Based on the above scheme, the second oil guide grooves are arranged in a spiral. As the sun gear rotates, the multiple second oil guide grooves have an axial oil pushing lubrication effect, and this effect is enhanced as the sun gear speed increases. This can effectively optimize the reliability of lubrication of the sun gear meshing tooth surface during high-speed heavy-load transmission.
[0026] In an optional embodiment, the outer diameter of the second shaft segment is smaller than the diameter of the tooth tip circle of the tooth body.
[0027] Based on the above scheme, the second shaft segment is less likely to interfere with the internal structure of the housing and is less likely to affect the installation of the sun gear.
[0028] Secondly, this utility model provides a gearbox, the gearbox comprising:
[0029] The sun gear structure described in any of the foregoing embodiments.
[0030] The beneficial effects of this utility model embodiment include, for example:
[0031] In summary, the sun gear structure provided in this embodiment, by providing a first oil guide groove on the wall of the second section of the mounting through hole, allows lubricating medium, such as lubricating oil, to enter the mounting through hole during the rotation of the sun gear. Guided by the first oil guide groove, it flows towards the internal spline teeth, increasing the amount of lubricating medium reaching the internal spline teeth, improving the lubrication effect, reducing wear and floating impact, and extending the service life of the internal spline teeth. Simultaneously, guided by the first oil guide groove, the lubricating medium can be discharged from the mounting through hole after passing through the internal spline teeth. The lubricating medium carrying away heat as it leaves the mounting through hole prevents heat dissipation from accumulating. Attached Figure Description
[0032] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0033] Figure 1 This is a schematic diagram of the sun gear structure from a first-view perspective in this embodiment;
[0034] Figure 2 This is a schematic diagram of the sun gear structure from a second perspective in this embodiment;
[0035] Figure 3 This is a cross-sectional schematic diagram of the sun gear structure in this embodiment;
[0036] Figure 4 This is a cross-sectional schematic diagram of the gearbox in this embodiment;
[0037] Figure 5 for Figure 4 A magnified schematic diagram of a portion of the image.
[0038] icon:
[0039] 100-Shaft body; 101-Assembly through hole; 110-First shaft section; 111-First end face; 112-First lubrication groove; 120-Second shaft section; 121-Second end face; 122-Second lubrication groove; 130-First oil guide groove; 140-Second oil guide groove; 200-Gear body; 210-Gear groove; 300-Internal spline; 001-Housing; 002-Drive shaft; 003-Sun gear structure. Detailed Implementation
[0040] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0041] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.
[0042] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0043] In the description of this utility model, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product is usually placed during use, they are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.
[0044] Furthermore, the terms "first" and "second" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.
[0045] It should be noted that, where there is no conflict, the features in the embodiments of this utility model can be combined with each other.
[0046] Please refer to Figures 1-3 This embodiment provides a sun gear structure 003, including:
[0047] The shaft 100, multiple teeth 200 and multiple internal spline teeth 300 are fixed on the outer circumferential surface of the shaft 100 and the multiple teeth 200 are arranged at intervals in the circumferential direction of the shaft 100.
[0048] The shaft 100 is provided with an assembly through hole 101, which includes a first hole section and a second hole section that are connected. Multiple internal spline teeth 300 are fixed on the hole wall of the first hole section and are arranged at intervals in the circumferential direction of the shaft 100. The hole wall of the second hole section is provided with a first oil guide groove 130 for guiding the lubricating medium toward the internal spline teeth 300.
[0049] As described above, the working principle of the sun gear structure 003 provided in this embodiment is as follows:
[0050] Please refer to Figures 1-5 The sun gear structure 003 is fitted onto the outside of the drive shaft 002 via the mounting through hole 101. The internal spline teeth 300 mesh with the external spline teeth on the outside of the drive shaft 002, and the first oil guide groove 130 is located near the motor side connected to the drive shaft 002. After the motor starts, it drives the drive shaft 002 to rotate, which in turn drives the sun gear structure 003 to rotate. The teeth 200 of the sun gear structure 003 can mesh with the planet gears, thereby driving the planet gears to rotate. Finally, the torque can be output through the gear ring meshing with the planet gears or the planet carrier that mounts the planet gears.
[0051] Because a first oil guide groove 130 is provided on the wall of the second section of the assembly through hole 101, during the rotation of the sun gear, the lubricating medium, such as lubricating oil, enters the assembly through hole 101 and, guided by the first oil guide groove 130, enters the location of the internal spline 300. This effectively lubricates the internal spline 300, improves its lubrication effect, reduces wear and floating impact, and extends its service life. Simultaneously, guided by the first oil guide groove 130, the lubricating medium can be discharged from the assembly through hole 101 after passing through the internal spline 300. The lubricating medium carrying away heat after leaving the assembly through hole 101 prevents heat dissipation from accumulating.
[0052] The following embodiments illustrate the details of the sun gear structure 003 of this application by way of example.
[0053] Please refer to Figures 1-3 In this embodiment, optionally, the sun gear structure 003 includes an integral shaft 100, multiple tooth bodies 200, and multiple internal spline teeth 300. The multiple tooth bodies 200 are located on the outer circumferential surface of the shaft 100, and are evenly spaced in the circumferential direction of the shaft 100, with a tooth groove 210 defined between adjacent tooth bodies 200. The multiple internal spline teeth 300 are fixed inside the shaft 100, and are evenly spaced in the circumferential direction of the shaft 100.
[0054] Optionally, the shaft body 100 may include a first shaft segment 110 and a second shaft segment 120 connected together. The first shaft segment 110 and the second shaft segment 120 are coaxially arranged, and their outer diameters may be the same. The shaft body 100 has a first end face 111 and a second end face 121 arranged opposite each other in its axial direction. The end of the first shaft segment 110 away from the second shaft segment 120 is the first end face 111, and correspondingly, the end of the second shaft segment 120 away from the first shaft segment 110 is the second end face 121. At the same time, the shaft body 100 is provided with a mounting through hole 101 extending in its axial direction. The mounting through hole 101 can be a circular hole, and the mounting through hole 101 is coaxially arranged with the shaft body 100.
[0055] The assembly through hole 101 includes a first hole segment and a second hole segment that are connected. The length of the first hole segment is basically the same as the length of the first shaft segment 110, and correspondingly, the length of the second hole segment is basically the same as the length of the second shaft segment 120.
[0056] During machining, multiple tooth bodies 200 are located on the outer peripheral surface of the first shaft segment 110, and multiple internal spline teeth 300 are located on the hole wall of the first hole segment. It should be understood that the number of tooth bodies 200 and internal spline teeth 300 is designed as needed, and is not specifically limited in this embodiment. Furthermore, the tooth bodies 200 can be helical teeth, meaning that the extending direction of the tooth body 200 forms an angle with the axis of the first shaft segment 110. Correspondingly, the extending direction of the tooth groove 210 formed between adjacent tooth bodies 200 also forms an angle with the axis of the first shaft segment 110.
[0057] Furthermore, the end of the first shaft segment 110 furthest from the second shaft segment 120 protrudes from the tooth body 200 by a predetermined length. That is, the first end face 111 protrudes from the tooth body 200, and the size of the protrusion of the tooth body 200 on the first end face 111 can be designed as needed. A first lubrication groove 112 is provided on the first end face 111. There can be multiple first lubrication grooves 112, which can be evenly spaced in the circumferential direction of the first shaft segment 110. For example, in this embodiment, there are eight first lubrication grooves 112. Each first lubrication groove 112 can be configured as an arc-shaped groove. The first lubrication groove 112 extends radially in the first shaft segment 110, with one end of each first lubrication groove 112 communicating with the first hole segment and the other end extending to the outer circumferential surface of the first shaft segment 110. Since the first end face 111 protrudes from the tooth body 200, the first lubrication groove is designed to not interfere with the location of the tooth body 200, that is, it will not damage the side of the tooth body 200, and it is not easy to weaken the structural strength of the tooth body 200, so the tooth body 200 is not easily damaged.
[0058] It is worth noting that the first lubrication channel 112 is designed as an arc-shaped channel, which facilitates processing, reduces stress concentration, and prevents cracking and damage. Obviously, in other embodiments, the first lubrication channel 112 can also be configured as a channel of other shapes.
[0059] In other embodiments, the number of first lubrication channels 112 is not limited to eight.
[0060] Meanwhile, a second lubrication channel 122 is provided on the second end face 121. There can be multiple second lubrication channels 122, which can be evenly spaced in the circumferential direction of the second shaft segment 120. For example, in this embodiment, there are eight second lubrication channels 122. Each second lubrication channel 122 can be configured as an arc-shaped channel. The second lubrication channel 122 extends radially in the second shaft segment 120. One end of each second lubrication channel 122 communicates with the second hole segment, and the other end extends to the outer circumferential surface of the second shaft segment 120.
[0061] It is worth noting that the second lubrication channel 122 is designed as an arc-shaped channel, which facilitates machining, reduces stress concentration, and prevents cracking and damage. Obviously, in other embodiments, the second lubrication channel 122 can also be configured as a channel of other shapes.
[0062] In other embodiments, the number of second lubrication channels 122 is not limited to eight.
[0063] Simultaneously, a first oil guide groove 130 is provided on the wall of the second bore section. There can be one first oil guide groove 130, which is configured as a spiral groove extending helically around the axis of the shaft 100. Furthermore, at least one of the multiple second lubrication channels 122 is connected to the first oil guide groove 130. One end of the first oil guide groove 130 extends to the second end face 121, and the other end extends to the connection point between the first and second bore sections, meaning the other end of the first oil guide groove 130 connects to the first bore section. When the sun gear rotates, the lubricating medium can enter the second bore section under the guidance of the second lubrication channel 122 and then enter the first oil guide groove 130. Under the action of the first oil guide groove 130, the lubricating medium can be guided axially to the location of the internal spline tooth 300, effectively lubricating the internal spline tooth 300. Due to the oil guiding function of the second lubrication channel 122, the lubricating medium is more likely to enter the second hole section. The large volume of lubricating medium in the first oil guide channel 130 allows for the guidance of more lubricating medium to the location of the internal spline 300, resulting in good lubrication. Simultaneously, after passing through the internal spline 300, the lubricating medium exits the assembly through-hole 101 from the second lubrication channel 122, carrying away heat from the assembly through-hole 101 and preventing the lubricating medium from accumulating inside the hole and hindering heat dissipation.
[0064] Optionally, a second oil guide groove 140 is provided on the outer circumferential surface of the second shaft segment 120. Multiple second oil guide grooves 140 can be provided, spaced apart circumferentially on the second shaft segment 120, and can be arranged spirally. One end of each second oil guide groove 140 communicates with the corresponding tooth groove 210, and the other end extends to the end face of the second shaft segment 120, i.e., to the second end face 121. The second oil guide groove 140 is used to guide the lubricating medium into the corresponding tooth groove 210. The spiral arrangement of the multiple second oil guide grooves 140 provides axial oil pushing lubrication as the sun gear rotates, and this effect is enhanced as the sun gear speed increases, effectively optimizing the reliability of lubrication of the sun gear meshing tooth surface during high-speed, heavy-load transmission.
[0065] It should be understood that since the outer diameters of the first shaft 100 and the second shaft 100 are basically the same, and the tooth body 200 is located on the outer circumferential surface of the first shaft 100, the outer diameter of the second shaft 100 is smaller than the diameter of the addendum circle of the tooth body 200. When assembling the sun gear, the outer circumferential surface of the second shaft 100 is exposed to the outside, which makes it less likely to interfere with other components in the housing, and also facilitates the entry of the lubricating medium into the second oil guide groove 140.
[0066] It should be understood that the lubricating medium in this embodiment may be, but is not limited to, lubricating oil.
[0067] Please refer to Figures 1-3 The sun gear structure 003 provided in this embodiment features a first oil guide groove 130 within the second bore section, a first lubrication channel 112 on the first end face 111, and a second lubrication channel 122 on the second end face 121. When the sun gear rotates, the lubricating medium can enter the second bore section from the second lubrication channel 122, flowing towards the internal spline tooth 300 under the guidance of the first oil guide groove 130. This effectively lubricates the internal spline tooth 300 and quickly dissipates heat, preventing overheating. Simultaneously, a second oil guide groove 140 is provided on the outer circumferential surface of the second shaft 100, allowing the lubricating medium to flow towards the tooth body 200 under the guidance of the second oil guide groove 140, thus effectively lubricating the tooth body 200. The sun gear exhibits low wear and impact during operation, has a long service life, and is less prone to abnormal noise.
[0068] Please refer to Figures 4-5 This embodiment also provides a gearbox, which includes a housing 001, a drive shaft 002, and a sun gear structure 003. The drive shaft 002 is rotatably mounted in the housing 001. The sun gear structure 003 uses its internal spline teeth 300 to mesh with the external spline teeth on the drive shaft 002, so that the drive shaft 002 can drive the sun gear structure 003 to rotate together.
[0069] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the protection scope of the claims.
Claims
1. A sun gear structure (003), characterized in that, include: The shaft (100), multiple teeth (200) and multiple internal spline teeth (300) are provided. The multiple teeth (200) are all fixed on the outer circumferential surface of the shaft (100) and the multiple teeth (200) are arranged at intervals in the circumferential direction of the shaft (100). The shaft (100) is provided with an assembly through hole (101), which includes a first hole section and a second hole section that are connected. The plurality of internal splines (300) are all fixed on the hole wall of the first hole section. The plurality of internal splines (300) are arranged at intervals in the circumferential direction of the shaft (100). The second hole section has a first oil guide groove (130) for guiding the lubricating medium toward the internal splines (300).
2. The sun gear structure (003) according to claim 1, characterized in that: The first oil guide groove (130) is configured as a spiral groove extending in a spiral line around the axis of the shaft (100).
3. The sun gear structure (003) according to claim 1, characterized in that: The shaft (100) has a first end face (111) and a second end face (121) disposed opposite to each other in its axial direction. The two ends of the mounting through hole (101) pass through the first end face (111) and the second end face (121) respectively. A first lubrication through groove (112) is provided on the first end face (111). One end of the first lubrication through groove (112) is connected to the first hole segment, and the other end of the first lubrication through groove (112) extends to the outer peripheral surface of the shaft (100).
4. The sun gear structure (003) according to claim 3, characterized in that: A second lubrication channel (122) is provided on the second end face (121). One end of the second lubrication channel (122) is connected to the first oil guide groove (130), and the other end of the second lubrication channel (122) extends to the outer peripheral surface of the shaft (100).
5. The sun gear structure (003) according to claim 4, characterized in that: The number of the first lubrication channel (112) and / or the second lubrication channel (122) is multiple, and the multiple first lubrication channels (112) are arranged at intervals in the circumferential direction of the shaft (100); the multiple second lubrication channels (122) are arranged at intervals in the circumferential direction of the shaft (100).
6. The sun gear structure (003) according to claim 4, characterized in that: The first lubrication channel (112) and / or the second lubrication channel (122) are configured as arc-shaped channels.
7. The sun gear structure (003) according to any one of claims 1-6, characterized in that: The shaft (100) includes a first shaft segment (110) and a second shaft segment (120) connected together. The plurality of teeth (200) are all fixed to the first shaft segment (110). The plurality of teeth (200) are arranged at intervals in the circumferential direction of the second shaft segment (120), and a tooth groove (210) is formed between adjacent teeth (200). The outer circumferential surface of the second shaft segment (120) is provided with a plurality of second oil guide grooves (140). The plurality of second oil guide grooves (140) are arranged at intervals in the circumferential direction of the second shaft segment (120). One end of each second oil guide groove (140) is connected to the corresponding tooth groove (210), and the other end extends to the end face of the second shaft segment (120). The second oil guide groove (140) is used to guide the lubricating medium into the corresponding tooth groove (210).
8. The sun gear structure (003) according to claim 7, characterized in that: The plurality of second oil guide grooves (140) are arranged in a spiral.
9. The sun gear structure (003) according to claim 7, characterized in that: The outer diameter of the second shaft segment (120) is smaller than the diameter of the tooth tip circle of the tooth body (200).
10. A gearbox, characterized in that, The gearbox includes: The sun gear structure (003) according to any one of claims 1-9.