A vehicle transmission

Abstract

The present application belongs to the field of vehicle transmission technology, and relates to a vehicle transmission. The transmission takes a planetary gear set as the core, selectively fixes the gear ring, planetary carrier or engages the first spline through the first coupling mechanism, and switches the output path through the second coupling mechanism, so that at least two forward gears and one reverse gear can be realized only by using a set of planetary rows with double planetary gears. The detachable and / or multi-stage planetary carrier design breaks through the limitation of the uniform assembly condition of the traditional planetary gear, makes the selection of the number of teeth of the sun gear and the gear ring more free, and improves the flexibility and design simplicity of the transmission ratio setting. The transmission also includes an intelligent lubrication system, which monitors the gear state through a visual sensor, controls the alignment of the lubrication channel and the oil supply position, and realizes directional lubrication of the key meshing positions. The present application has compact structure, high transmission efficiency, and is suitable for vehicle transmission systems.

Description

Technical Field

[0001] This invention belongs to the field of vehicle transmission technology, and specifically relates to a vehicle transmission. Background Technology

[0002] Planetary transmissions, as efficient and compact transmission devices, are widely used in vehicle transmission systems, especially suitable for scenarios with high requirements for space layout, transmission efficiency, and multi-gear output, such as the powertrains of passenger cars, commercial vehicles, and special vehicles. Traditional planetary gear transmissions typically include a sun gear, ring gear, planet carrier, and several planet gears. Different gear ratios are achieved by braking or connecting one of these components. Their structure is relatively mature, enabling multi-gear output and high power density.

[0003] However, traditional planetary gear transmission designs have significant constraints. To achieve a uniform circumferential arrangement of multiple planetary gears and their simultaneous and correct meshing with the sun gear and ring gear, conditions such as geometric assembly and adjacent space must be met; that is, the relationship (z) must be satisfied. r +z s ) / n∈Z (where z r z is the number of teeth on the gear ring. s (where n is the number of teeth on the sun gear, n is the number of planetary gear sets, and Z is an integer). This condition essentially stems from the fact that during the rotation of the planet carrier, the cumulative tooth pitch of the sun gear and the ring gear relative to the planet carrier must be synchronized; otherwise, the planet gears will not be able to mesh with both simultaneously, causing transmission interference, vibration, or failure. This condition severely restricts the freedom of choice in the number of teeth on the sun gear and the ring gear, often requiring repeated adjustments to the transmission ratio design around this constraint, increasing design time and manufacturing costs, and proving inflexible, especially in situations requiring a specific transmission ratio or spatial layout.

[0004] On the other hand, existing planetary gear transmissions mostly use splash lubrication or fixed oil channel injection for lubrication. The lubrication path and effect are relatively fixed, making it difficult to accurately control the real-time lubrication needs of specific gear pairs under high load, high speed or frequent gear shifting conditions. This can easily lead to insufficient local lubrication, excessive temperature rise or accelerated wear, affecting transmission reliability and service life.

[0005] Therefore, how to overcome the limitations of traditional assembly conditions on tooth number matching, improve the flexibility of transmission ratio design, and achieve intelligent and directional lubrication of key meshing parts while maintaining the compact and efficient characteristics of planetary gear transmission structures has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0006] The present invention aims to provide a vehicle transmission with a compact structure, integrated reverse gear function, and the ability to overcome the limitations of traditional planetary gear assembly conditions. It achieves free setting of transmission ratio through a detachable / multi-stage planetary carrier design and has intelligent directional lubrication capability.

[0007] A vehicle transmission, comprising: The input shaft is equipped with a first spline and a sun gear for inputting torque. The output shaft is equipped with a third spline for outputting torque. A planetary gear set comprising a sun gear, a ring gear, and a planet carrier, wherein at least two planet gears are rotatably mounted on the planet carrier, the ring gear and the sun gear are configured to mesh with the at least one planet gear, and each planet carrier is commonly connected to a second spline; The first coupling mechanism is used to achieve three selective connection states: fixing or rotatable the gear ring; fixing or revolving the planet carrier around the sun gear; and engaging or disengaging the first spline from the planet carrier. The second coupling mechanism selectively engages or disengages the third spline with either the ring gear or the second spline of the planetary gear set. This transmission, with the planetary gear set as its core transmission unit, combined with two independently controllable coupling mechanisms, forms a highly integrated transmission module. Through the precise selection of the ring gear and planetary carrier states (fixed or rotating) by the first coupling mechanism, and the flexible switching of the output path (coupling the ring gear or the second spline) by the second coupling mechanism, a variety of different gear ratios can be combined using only one planetary gear set. This achieves power transmission of at least two forward gears and one reverse gear within a limited space, simplifying the transmission structure, reducing weight, and improving transmission efficiency and power density.

[0008] A vehicle transmission, wherein the planetary carrier includes at least a first planetary carrier, the first planetary carrier being detachably connected to a second spline, the first planetary carrier being provided with meshing teeth for meshing with the first spline.

[0009] A vehicle transmission, wherein a first planetary gear and a second planetary gear are mounted on a first planetary carrier; When the first spline engages with the first planetary carrier, the first planetary carrier rotates under the drive of the first spline, which in turn drives the second spline to rotate. This technical feature defines that the torque of the input shaft is transmitted through the first planetary gear or the first spline, while the torque of the ring gear is transmitted through the second planetary gear. This allows the power flow input or output by the sun gear and the ring gear to be clearly and independently distributed to the two planetary gears, avoiding the intersection and interference of power transmission paths.

[0010] As in Example 1, when the first coupling mechanism fixes the position of the gear ring and the second coupling mechanism engages the second spline and the third spline, the transmission path of the entire transmission mechanism is as follows: the transmission torque is transmitted along the sun gear, the first planetary carrier, the second spline, and to the third spline, and the overall transmission ratio is... , z s z is the number of teeth on the sun gear. r Z1 represents the number of teeth on the internal gear ring, Z2 represents the number of teeth on the first planetary gear, and Z3 represents the number of teeth on the second planetary gear.

[0011] When the first coupling mechanism fixes the position of the first planetary carrier and the second coupling mechanism engages the gear ring with the third spline, the transmission path of the entire transmission mechanism is as follows: the transmission torque is transmitted along the sun gear, the first planetary gear, the second planetary gear, and the gear ring to the third spline, with a transmission ratio of [value missing]. Therefore, the final result is negative, and reverse gear can be achieved in this state.

[0012] When the first coupling mechanism engages the first spline with the first planetary carrier, the gear ring is driven to rotate by the second planetary gear. When the second coupling mechanism engages the second spline with the third spline, the transmission torque is transmitted along the first spline, the first planetary carrier, the second spline to the third spline, and the transmission ratio is 1.

[0013] Another idling state is provided, in which the first coupling mechanism and the second coupling mechanism make the planetary carrier and the gear ring not fixed, the second spline and the third spline disengage, and the entire transmission mechanism is in an idling state, that is, the neutral state of the transmission.

[0014] In traditional single planetary gear transmissions, to ensure that n planetary gear sets are evenly installed along the circumference and stably mesh with the sun gear and ring gear simultaneously, certain conditions must be met, such as geometric assembly conditions and adjacent spatial conditions. This condition arises because when the planet carrier rotates through the evenly divided angle between adjacent planet gears, the cumulative tooth pitch of the sun gear and ring gear relative to the planet carrier must simultaneously be an integer number of teeth; otherwise, the next planet gear will not be able to mesh correctly with either of them. This constraint is independent of the number of teeth on the planet gears themselves, and depends only on the number of teeth z on the sun gear. s Number of teeth on the gear ring z r The number of planetary gear sets, n, becomes an insurmountable rigid constraint in traditional planetary gear set design. This also means that gear ratio adjustment and tooth number optimization must prioritize satisfying this divisibility relationship, increasing design and manufacturing constraints.

[0015] In the field of industrial design and manufacturing, the adjustment of the transmission ratio of existing planetary gear transmissions is often limited by the number of teeth z of the sun gear. s Number of teeth on the gear ring z r The fixed relationship conditions that must be met often cannot be satisfied when changing the gear ratio due to the combination of teeth (z). r +z sIf (z) / n∈Z (where Z is an integer), the sun gear and ring gear must be redesigned and replaced. This not only severely limits the adjustment space of gear parameters but also leads to extended design cycles, increased manufacturing costs, and increased system fit complexity. In contrast, the transmission scheme provided in Embodiment 1 of this invention only needs to satisfy (z) / n∈Z (where Z is an integer). 1* z r + z 2* z s (n ∈ Z, where Z is an integer), or by using offset machining of planetary gears to avoid the influence of assembly conditions, when the transmission ratio needs to be adjusted, the sun gear and the first planetary gear, or the ring gear and the second planetary gear, can be selectively replaced without having to replace both the sun gear and the ring gear simultaneously (replacing both the sun gear and the ring gear is costly). This structure significantly improves the flexibility of transmission ratio configuration, making the selection and optimization of gear tooth count more free, thus achieving more efficient tooth count matching and transmission ratio optimization in industrial design, while reducing the complexity of design adjustment and manufacturing assembly.

[0016] A vehicle transmission includes a planetary carrier comprising at least a fourth planetary carrier, the fourth planetary carrier having meshing teeth for engaging with a first spline, and the fourth planetary carrier mounting at least two second planetary carriers and a third planetary carrier rotatable about its axis. The combination of multiple planetary carriers and multiple planetary gears can distribute the transmission load under different operating conditions, reduce the force on individual planetary gears, and improve the durability and reliability of the gear system.

[0017] A vehicle transmission, wherein a third planetary gear is mounted on a second planetary carrier, and a fourth planetary gear is mounted on the third planetary carrier; When the first spline engages with the fourth planetary carrier, the fourth planetary carrier rotates under the drive of the first spline, which in turn drives the second spline to rotate.

[0018] As in Example 2, when the first coupling mechanism fixes the position of the gear ring and the second coupling mechanism engages the second spline and the third spline, the transmission path of the entire transmission mechanism is as follows: the transmission torque is transmitted along the sun gear, the third and fourth planetary carriers, the second planetary carrier, and the second spline to the third spline, and the transmission ratio of the entire path is 1-z. r / z s Therefore, the final result is negative, indicating reverse gear.

[0019] When the first coupling mechanism fixes the position of the first planetary carrier and the second coupling mechanism engages the gear ring with the third spline, the transmission path of the entire transmission mechanism is as follows: the transmission torque is transmitted along the sun gear, the third planet gear, the fourth planet gear, the gear ring, and to the third spline, with a transmission ratio of z. r / z s 。

[0020] When the first coupling mechanism engages the first spline with the second planetary carrier, the gear ring will rotate under the influence of the fourth planetary gear. When the second coupling mechanism engages the second spline with the third spline, the transmission torque is transmitted along the first spline, the second planetary carrier, and the second spline to the third spline, with a transmission ratio of 1. In traditional planetary gear mechanism design, the uniformly distributed assembly condition (z...) r +z s The condition ) / n∈Z (where Z is an integer) constitutes a rigid constraint, limiting the free matching of the number of teeth between the sun gear and the ring gear. This often necessitates the redesign of both the sun gear and the ring gear when adjusting the transmission ratio, increasing development time and manufacturing costs. Embodiment 2 of this invention achieves modularity and path independence for the planetary gear set by setting a second and a third planetary carrier and installing the third and fourth planetary gears respectively. Each planetary carrier and its corresponding planetary gear can independently determine the number of teeth and installation phase according to transmission requirements, thus allowing for different planetary gear sets to be configured to meet the constraints, making transmission ratio adjustments more flexible and convenient.

[0021] A vehicle transmission includes an assembly housing, which is a cylindrical structure with mounting holes inside for mounting a second planetary carrier and a third planetary carrier. The assembly shell also has a hollow hole, which is used to accommodate the sun gear and provide space for the meshing of the sun gear and the third planet gear; The assembly housing also includes a planetary gear mounting section, which provides accommodating and meshing space for the third and fourth planetary gears.

[0022] Furthermore, the side wall of the assembly shell is provided with lubrication channels, which lead directly from the periphery of the side wall to the meshing point of the sun gear and the third planet gear, so that the lubricating oil can directly lubricate the meshing point of the sun gear and the third planet gear. The sidewall of the planetary gear mounting section has a curved structure extending from the outer periphery to the inner wall, which is used to guide the lubricating oil to the meshing point of the third planetary gear and the fourth planetary gear, so that the lubricating oil can directly lubricate the meshing point of the third planetary gear and the fourth planetary gear.

[0023] A vehicle transmission includes a transmission housing, a first oil passage on the transmission housing, an outlet of the first oil passage facing the gap between the assembly housing and the gear ring, and an oil pump at the outlet of the first oil passage.

[0024] A vehicle transmission, further comprising: A vision sensor, built into the transmission, is used to monitor the transmission status of each gear; The control system is connected to the external lubrication box, the first coupling mechanism, and the second coupling mechanism via signals.

[0025] Furthermore, the control system is configured to perform the following lubrication controls: When it is detected that enhanced lubrication of the sun gear and the third planet gear is required, the second coupling mechanism is switched to the neutral position, and the first spline is driven to engage with the fourth planet carrier through the first coupling mechanism, so that the inlet of the lubrication channel rotates and stops at the oil supply position corresponding to the outlet of the first oil channel. Then, the lubricating oil is released, so that the lubricating oil is delivered to the sun gear and the third planet gear through the lubrication channel for lubrication. When it is detected that enhanced lubrication of the third and fourth planetary gears is required, the second coupling mechanism is switched to neutral, and the first spline is driven to engage with the fourth planetary carrier through the first coupling mechanism, so that the opening of the corresponding planetary gear mounting part rotates and stops at the oil supply position corresponding to the first oil passage outlet. Then, the lubricating oil is released, so that the lubricating oil is delivered to the third and fourth planetary gears through the planetary gear mounting part for lubrication.

[0026] The lubrication system is designed with the first oil passage outlet in mind to ensure continuous oil spray lubrication of the gear ring and the fourth planetary gear, so no additional directional lubrication operation is required for this gear pair.

[0027] The system is equipped with vision sensors to monitor the transmission and friction status of each gear pair in real time. When it is detected that the sun gear and the third planetary gear need additional lubrication, the system automatically executes the control process: First, the second coupling mechanism is placed in neutral and engaged with the fourth planetary carrier through the first spline. Then, the input shaft slowly rotates, causing the lubrication channel opening of the assembly housing to align with the oil supply position of the first oil channel outlet. At this time, the first coupling mechanism locks the positions of the fourth, second, and third planetary carriers (i.e., the assembly housing stops rotating), but the input shaft continues to rotate (i.e., the sun gear and the third planetary gear rotate on their own axis but not around the sun), allowing the lubricating oil to fully cover all positions at the meshing points of the sun gear and the third planetary gear. The lubricating oil is sprayed into the lubrication channel through the oil pump and directly delivered to the meshing parts of the sun gear and the third planetary gear, achieving point-to-point lubrication.

[0028] If the system detects that the third and fourth planetary gears require lubrication, it employs a similar logic: after the second coupling mechanism is in neutral and the assembly housing is fixed by the first spline, the input shaft is slowly rotated so that the outlet of the planetary gear mounting part is aligned with the oil supply position of the first oil passage. At this time, the first coupling mechanism locks the positions of the fourth, second, and third planetary carriers (i.e., the assembly housing stops rotating), but the input shaft continues to rotate (i.e., the third and fourth planetary gears rotate on their own axis but not around the sun), allowing the lubricating oil to fully cover all positions at the meshing points of the third and fourth planetary gears. The lubricating oil is then sprayed into the planetary gear mounting part and flows directly to the meshing area of ​​the third and fourth planetary gears, completing the lubrication.

[0029] Throughout the control process, the system calculates the stopping angle of the assembly housing in real time based on the input shaft rotation, thereby ensuring that the openings of the lubrication channels and planetary gear mounting parts are accurately aligned with the oil supply position, achieving a reliable and directional lubrication supply.

[0030] The advantages of this invention are as follows: Through an innovative detachable / multi-stage planetary carrier design, it completely breaks through the limitations of the traditional planetary gear's requirement for uniformly distributed assembly, allowing for extremely flexible selection of the number of teeth on the sun gear and ring gear, greatly improving the flexibility and ease of design in setting the transmission ratio; at least two forward gears and one reverse gear can be achieved using only one planetary gear set and two coupling mechanisms, resulting in a highly compact structure, reduced weight, and increased power density; the intelligent directional lubrication system provides precise lubrication of key meshing parts based on real-time monitoring, enhancing the system's reliability and durability under high-speed, high-load conditions; simultaneously, the modular planetary carrier and planetary gear set design facilitates load distribution and maintenance, reduces manufacturing and assembly complexity, and overall improves the transmission's engineering adaptability and economy. Attached Figure Description

[0031] To more clearly illustrate the embodiments of the present invention or the technical solutions in 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 merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of the transmission mechanism in Embodiment 1 of the present invention; Figure 2 This is a front view of the transmission mechanism in Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the transmission mechanism in Embodiment 2 of the present invention; Figure 4 This is a front view of the transmission mechanism in Embodiment 2 of the present invention; Figure 5 This is a schematic diagram of the transmission of a conventional planetary gear mechanism according to the present invention; Figure 6 This is a front view of the conventional planetary gear mechanism of the present invention; Figure 7 This is a schematic diagram showing the positional relationship between the assembly housing and each gear of the present invention; Figure 8 This is a schematic diagram of the assembled shell structure of the present invention; Figure 9 This is a schematic diagram of lubricating oil entering the lubrication channel in the first oil passage of the present invention; Figure 10 This is a schematic diagram of the first oil passage lubricating oil entering the planetary gear mounting part of the present invention.

[0033] Figure Descriptions: 2-Planetary gear set, 11-Input shaft, 12-Output shaft, 12a-Third spline, 21-Sun gear, 22-Ring gear, 23-Planet carrier, 23a-First planet carrier, 23b-Second planet carrier, 23c-Third planet carrier, 23d-Fourth planet carrier, 24-Second spline, 25-First planet gear, 26-Second planet gear, 27-Third planet gear, 28-Fourth planet gear, 29-First spline, 31-First coupling mechanism, 32-Second coupling mechanism, 41-Assembly housing, 42-Gearbox housing, 411-Mounting hole, 412-Hollow hole, 413-Planet gear mounting part, 414-Lubrication channel, 421-First oil passage, 421a-Oil pump. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] The concepts involved in this application will first be described with reference to the accompanying drawings. It should be noted that the following descriptions of various concepts are only for the purpose of making the content of this application easier to understand and do not constitute a limitation on the scope of protection of this application; furthermore, the embodiments and features in the embodiments of this application can be combined with each other unless otherwise specified. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0036] Example 1: See attached document Figure 1 , Figure 2 As shown, the transmission described in this embodiment includes an input shaft 11, an output shaft 12, a planetary gear set 2, a first coupling mechanism 31, and a second coupling mechanism 32. The input shaft 11 is used to receive torque from a motor or engine, and a sun gear 21 and a first spline 29 are fixedly mounted on it. The output shaft 12 is used to output the changed torque to the differential or drive axle, and a third spline 12a is fixed at its end.

[0037] Planetary gear set 2 is the core transmission unit of the gearbox. In actual engineering, there are usually three or more planetary gear sets 2, which are evenly installed along the circumference of the gear ring. Taking one of the planetary gear sets 2 as an example, the component analysis is carried out.

[0038] Internally, it includes a sun gear 21, which is fixed to the input shaft 11; Gear ring 22, an internal gear, is encircled at the center.

[0039] The first planetary carrier 23a is a specific component of the planetary carrier 23. The first planetary carrier 23a is rotatably supported on the shaft by bearings. The first planetary carrier 23a is designed as a detachable structure, with one side detachably connected to a second spline 24 via a spline or bolt. A key feature is that the end of the first planetary carrier 23a facing the input shaft has external meshing teeth (spline teeth in this embodiment).

[0040] The planetary gear set 2 has a first planetary gear 25 and a second planetary gear 26 mounted on the first planetary carrier 23a. The first planetary gear 25 is constantly meshed with the sun gear 21, and the second planetary gear 26 is constantly meshed with the ring gear 22.

[0041] The first spline 29 is fixed to the input shaft 11 and arranged side by side with the sun gear 21. Its design position allows its external teeth to engage or disengage with the external meshing teeth at the end of the first planetary carrier 23a via the first coupling mechanism 31.

[0042] The first coupling mechanism 31, in this embodiment, can be a shift execution module integrating multiple synchronizers, clutches, and internal spline couplings. It is configured to selectively achieve one of the following three states: State A (Fixed Gear Ring): Lock the gear ring 22 onto the transmission housing to prevent it from rotating.

[0043] State B (Fixed Planetary Carrier): The first planetary carrier 23a is locked to the transmission housing, making it fixed and not rotating.

[0044] State C (engaging the first spline and the planetary carrier): The external teeth of the first spline 29 are engaged with the meshing teeth at the end of the first planetary carrier 23a through the internal spline coupling, thereby connecting the two into one.

[0045] The second coupling mechanism 32, in this embodiment, can be a coupling. It is configured to selectively engage the third spline 12a with the second spline 24, or with the gear ring 22 (or its extended gear ring connecting sleeve), or be in an intermediate neutral position, such that the third spline 12a is not engaged with either.

[0046] Next, we will introduce the working modes and transmission ratios of each gear. By controlling the state of the first coupling mechanism 31 and the second coupling mechanism 32, the following four working modes can be achieved.

[0047] Forward gear 1 (low gear): The first coupling mechanism 31 is in state A, i.e., the gear ring 22 is locked. The second coupling mechanism 32 engages the third spline 12a with the second spline 24. The entire power transmission path is: input shaft 11 → sun gear 21 → first planetary gear 25 and second planetary gear 26 → (driving the first planetary carrier 23a to revolve around the fixed gear ring 22) → first planetary carrier 23a → second spline 24 → third spline 12a → output shaft 12. At this time, the planetary gear set works as a reducer. The first transmission ratio i1 = Among them, z s For the sun gear with 21 teeth, z r Z1 has 22 teeth on the ring gear, Z2 has 25 teeth on the first planetary gear, and Z3 has 26 teeth on the second planetary gear. This is a reduction ratio greater than 1.

[0048] Reverse gear: The first coupling mechanism 31 is in state B, i.e., the first planetary carrier 23a is locked. The second coupling mechanism 32 engages the third spline 12a with the ring gear 22. The entire power transmission path is: input shaft 11 → sun gear 21 → first planetary gear 25 → second planetary gear 26 → (driving the ring gear 22 to rotate in the opposite direction) → ring gear 22 → second coupling mechanism 32 → third spline 12a → output shaft 12. At this time, the planetary gear set works as a fixed-axis gear system, and the output direction is opposite to the input direction. Reverse gear ratio i r = The negative sign indicates that the rotation direction is opposite.

[0049] Forward Gear 2 (Direct Drive): The first coupling mechanism 31 is in state C, i.e., engaging the first spline 29 and the first planetary carrier 23a. At this time, since the first planetary carrier 23a is driven by the first spline 29, its rotational speed is synchronized with the input shaft 11, resulting in no power transmission between the first planetary gear 25 and the sun gear 21, although they are in contact. The ring gear 22 is driven to rotate by the second planetary gear 26. The second coupling mechanism 32 engages the third spline 12a with the second spline 24. The entire power transmission path is: input shaft 11 → first spline 29 → first planetary carrier 23a (directly driven via meshing teeth) → second spline 24 → second coupling mechanism 32 → third spline 12a → output shaft 12. The third transmission ratio i2 = 1, achieving direct drive with high efficiency.

[0050] Neutral: The first coupling mechanism 31 is in the released state, neither fixing the gear ring 22 nor the planet carrier 23a, nor engaging the first spline 29. The second coupling mechanism 32 is in the intermediate neutral position, with the third spline 12a not engaging with either the second spline 24 or the gear ring 22. At this time, the entire planetary gear set 2 can rotate freely, and no effective power transmission path can be formed to the output shaft 12, thus achieving neutral.

[0051] The following example will illustrate the technical advantage of this embodiment's transmission mechanism in facilitating changes in the transmission ratio. Assume that in the initial design of Embodiment 1, the transmission parameters are as follows: number of sun gear teeth z... s =24, Number of teeth on the gear ring z r =72, the number of teeth on the first planetary gear z1=20, the number of teeth on the second planetary gear z2=28, and the number of planetary gears n=3.

[0052] According to the forward gear ratio formula in Example 1: .

[0053] Now, suppose that due to changes in vehicle requirements, the gear ratio needs to be adjusted from approximately 3.14 to approximately 2.5. In a traditional planetary gear mechanism design (see attached...), Figure 5 , Figure 6 In this process, both the sun gear 21 and the ring gear 22 must be replaced simultaneously, and the new adjustment gear count must meet stringent (z) requirements. r +z s Given the condition ) / n∈Z (Z is an integer), matching the number of teeth is difficult and the adjustment cost is high.

[0054] This solution only replaces the sun gear 21 and the first planetary gear 25 module (e.g., Figure 2 As shown, the first planet carrier 23a is detachable, making it easy to replace the first planet gear 25 on it and pair it with a new sun gear 21, while keeping the ring gear 22 and the second planet gear 26 unchanged, thereby significantly reducing adjustment costs.

[0055] Increase the number of teeth on the new sun gear The number of teeth on the new first planetary gear changes to 30. It becomes 18.

[0056] The new number of teeth satisfies the constraints of Example 1. (Z is an integer).

[0057] Adjusted transmission ratio The value is approximately 2.5, which meets the target.

[0058] As can be seen from the above examples, in the design of traditional planetary gear mechanisms (see appendix) Figure 5 , Figure 6 In this context, the transmission ratio adjustment is limited by (z) r +z s The strict condition that n ∈ Z (where Z is an integer) often requires replacing the sun gear and ring gear in pairs. This invention transforms the constraint condition into (z) / n ∈ Z. 1* z r + z 2* z s) / n∈Z (Z is an integer), when adjusting the transmission ratio, only the sun gear 21 and the first planet gear 25 (or the ring gear 22 and the second planet gear 26) need to be replaced, which significantly improves the freedom of gear parameter selection and reduces the complexity and cost of design changes, especially when a smaller transmission ratio needs to be designed.

[0059] Example 2: Building upon the advantages of breakthroughs in traditional assembly conditions and compact structure demonstrated in Example 1, this example provides a structurally reinforced solution for application scenarios requiring higher power density, better load distribution, and more complex transmission ratio settings (such as heavy-duty electric vehicles or high-performance electric drive axles). This solution innovatively introduces a composite, multi-level nested planetary carrier mechanism. This design not only inherits all the advantages of "liberating assembly constraints" from Example 1, but also significantly improves the transmission's torque capacity, system stiffness, and durability by distributing the transmission load to multiple independent planetary gear shafts. Simultaneously, it provides more physical adjustment dimensions for fine-tuning the transmission ratio.

[0060] See appendix Figure 3 , Figure 4 As shown, this transmission also includes an input shaft 11, an output shaft 12, a planetary gear set 2, a first coupling mechanism 31, and a second coupling mechanism 32. Its core difference from Embodiment 1 lies in the planetary carrier portion.

[0061] The input and output sections are the same as in Embodiment 1, with the input shaft 11 fixedly connected to the sun gear 21 and the first spline 29; and the output shaft 12 fixedly connected to the third spline 12a.

[0062] The core innovation of Planetary Gear Set 2 lies in the planet carrier, including: The internal sun gear 21 is fixed to the input shaft 11.

[0063] Gear ring 22, an internal gear, surrounds the center.

[0064] The fourth planetary carrier 23d is the main planetary carrier, serving as the core load-bearing and linkage structure of the planetary carrier assembly. The fourth planetary carrier 23d has meshing teeth at its ends, and an external spline is machined on the end facing the input shaft for engagement or disengagement with the first spline 29 via the first coupling mechanism 31. The other side is detachably connected to a second spline 24 via splines or bolts. Secondary planetary carriers are mounted on the fourth planetary carrier 23d. Instead of directly mounting planetary gears, at least two secondary planetary carriers—the second planetary carrier 23b and the third planetary carrier 23c—are mounted via bearings. Each of these two secondary planetary carriers has an independent axis of rotation, parallel to but not aligned with the main axis.

[0065] The second planetary carrier 23b and the third planetary carrier 23c are modular sub-units. Each sub-planetary carrier (such as the second planetary carrier 23b) has its own planetary gear (such as the third planetary gear 27) fixedly mounted on it. Similarly, the third planetary carrier 23c has a fourth planetary gear 28 fixedly mounted on it. When the first spline 29 is not engaged with the fourth planetary carrier 23d, the third planetary gear 27 is constantly meshed with the sun gear 21, and the fourth planetary gear 28 is constantly meshed with the ring gear 22. Importantly, in this embodiment, the third planetary gear 27 and the fourth planetary gear 28 can rotate independently, and their rotational speed relationship is determined by the motion of their respective second planetary carrier 23b and third planetary carrier 23c.

[0066] The first coupling mechanism 31 has three selective connection states: locking the gear ring 22, locking the fourth planetary carrier 23d (i.e., locking the main planetary carrier), and engaging the end meshing teeth of the first spline 29 and the fourth planetary carrier 23d via a coupling. The second coupling mechanism 32 selectively engages the third spline 12a with either the gear ring 22 or the second spline 24 (i.e., the fourth planetary carrier 23d).

[0067] Next, we will introduce the working modes and transmission ratios of each gear. The logic of the working modes is the same as that of Example 1, but the internal torque transmission path is more sophisticated due to the multi-stage planetary carrier.

[0068] Reverse gear: The first coupling mechanism 31 locks the gear ring 22, and the second coupling mechanism 32 engages the third spline 12a and the second spline 24 (i.e., the fourth planetary carrier 23d). The entire power transmission path is: input shaft 11 → sun gear 21 → third planetary gear 27 and fourth planetary gear 28 → (driving the second planetary carrier 23b to rotate around its own axis) → because the gear ring 22 is fixed, the movement of the second planetary carrier 23b and the third planetary carrier 23c will force the fourth planetary carrier 23d to revolve around the input shaft 11 → fourth planetary carrier 23d → second spline 24 → third spline 12a → output shaft 12. At this time, the second planetary carrier 23b, the third planetary carrier 23c and the planetary gear set 2 on them together play the role of a "compound planetary gear", with a transmission ratio of 1-z. r / z s During the transmission of torque from the sun gear 21 to the fourth planetary carrier 23d, it is distributed across multiple independent second and third planetary carrier shaft systems, significantly reducing the load on individual gear pairs.

[0069] Forward Gear 1: The first coupling mechanism 31 locks the fourth planetary carrier 23d (main planetary carrier), and the second coupling mechanism 32 engages the third spline 12a and the gear ring 22. The entire power transmission path is: input shaft 11 → sun gear 21 → third planetary gear 27 → (because the fourth planetary carrier 23d is fixed, the third planetary gear 27 can only rotate on a fixed spatial track) → fourth planetary gear 28 → gear ring 22 → third spline 12a → output shaft 12. In this state, the sliding gear train becomes a fixed-axis gear train, and the transmission ratio zr / z s The load is also shared by multiple sets of parallel planetary gear pairs (third planetary gear 27, sun gear 21, fourth planetary gear 28, and ring gear 22).

[0070] Forward Gear 2 (Direct Drive): The first coupling mechanism 31 engages the first spline 29 and the fourth planetary carrier 23d, and the second coupling mechanism 32 engages the third spline 12a and the second spline 24. The power transmission path is: input shaft 11 → first spline 29 → (directly driven by end meshing teeth) fourth planetary carrier 23d → second spline 24 → third spline 12a → output shaft 12. At this time, although the sun gear 21 and the third planetary gear 27 are in contact, there is no power transmission. The gear ring 22 is driven to rotate by the fourth planetary gear 28. At this time, the transmission ratio of the device is 1.

[0071] Neutral: The first coupling mechanism 31 is in the released state, neither fixing the gear ring 22 nor the planet carrier 23a, nor engaging the first spline 29. The second coupling mechanism 32 is in the intermediate neutral position, with the third spline 12a not engaging with either the second spline 24 or the gear ring 22. At this time, the entire planetary gear set 2 can rotate freely, and no effective power transmission path can be formed to the output shaft 12, thus achieving neutral.

[0072] Compared to Example 1, the second planetary carrier 23b and the third planetary carrier 23c share the meshing force from the sun gear 21 and the ring gear 22, while the fourth planetary carrier 23d mainly bears the revolution torque. This load decoupling and distribution design greatly improves the rigidity of the entire gear system, reduces gear eccentricity, and lowers the risk of failure of individual bearings, making it particularly suitable for commercial vehicle operating conditions with high torque and high impact.

[0073] In Embodiment 2, by setting up a second planetary carrier 23b and a third planetary carrier 23c and respectively installing a third planetary gear 27 and a fourth planetary gear 28, the modularity and path independence of the planetary gear set 2 are achieved. The number of teeth and installation phase of each planetary carrier and its corresponding planetary gear can be easily and independently determined according to transmission requirements, making it more convenient to adjust the transmission ratio.

[0074] Example 3: This embodiment, based on Embodiment 2, further discloses a vehicle transmission structure with intelligent directional lubrication, particularly suitable for commercial vehicles and construction machinery subjected to high loads, high speeds, or frequent gear shifts. When the lubricating oil level in the transmission of this type of commercial vehicle or construction machinery is low, this system can act as a supplementary lubrication structure. Combined with visual sensor monitoring and intelligent control logic, it achieves precise lubrication of key gear pairs, thereby improving transmission efficiency, extending gear life, and prolonging operating time.

[0075] See attached document Figure 7 , Figure 8 As shown, the overall structure of the vehicle transmission in this embodiment can refer to the planetary gear set layout in Embodiment 2, with the addition of features such as an assembly housing 41, lubrication channels 414, a transmission housing 42 and a first oil passage 421, and a monitoring and control system. The assembly housing 41 is made of high-strength alloy casting or forging, and has a cylindrical structure with multiple mounting holes 411 inside for detachably mounting the second planetary carrier 23b and the third planetary carrier 23c. A hollow hole 412 is provided in the center of the assembly housing 41 to accommodate the sun gear 21 and ensure the meshing space between the sun gear 21 and the third planetary gear 27. The interior of the assembly housing 41 also has multiple planetary gear mounting parts 413, each with a semi-enclosed structure, for accommodating and positioning the meshing area between the third planetary gear 27 and the fourth planetary gear 28. At least one lubrication channel 414 is radially formed on the side wall of the assembly housing 41. The lubrication channel 414 extends from the outer wall of the assembly housing 41 all the way to the meshing area between the sun gear 21 and the third planetary gear 27. The lubrication channel 414 has its inlet located on the outer circumference of the assembly housing 41, and its outlet directly aligned with the meshing point of the sun gear 21 and the third planetary gear 27. Furthermore, the inner wall of the planetary gear mounting section 413 is designed as a curved structure inclined towards the meshing area, facilitating the natural flow of lubricating oil to the meshing point of the third planetary gear 27 and the fourth planetary gear 28. A first oil passage 421 is provided on the gearbox housing 42, with its outlet directly facing the radial clearance between the assembly housing 41 and the gear ring 22. An oil pump 421a exiting the first oil passage 421 is connected to an external lubrication system, allowing for controlled lubricating oil injection. High-definition vision sensors, which can be oil-resistant monitoring cameras, are arranged at key locations inside the gearbox (such as near the sun gear 21 and the planetary gear meshing area) to capture the meshing state and oil film distribution of the gear pairs in real time. The control system is connected to the vision sensors, the first coupling mechanism 31, the second coupling mechanism 32, and the external oil tank, possessing intelligent decision-making capabilities based on image recognition and operating condition signals.

[0076] The lubrication system in this embodiment has two lubrication modes: continuous lubrication at normal pressure and targeted strong lubrication. Normal pressure lubrication involves continuously spraying oil into the gap between the gear ring 22 and the assembly housing 41 through the first oil passage 421, achieving basic lubrication of the gear ring 22 and the fourth planetary gear 28. When the visual sensor detects insufficient lubrication or a thinning oil film in the meshing area between the sun gear 21 and the third planetary gear 27, or between the third planetary gear 27 and the fourth planetary gear 28, the system automatically initiates the targeted strong lubrication process.

[0077] See attached document Figure 3 , Figure 4 , Figure 7 , Figure 8 , Figure 9When the sun gear 21 and the third planetary gear 27 require strong lubrication, the control system places the second coupling mechanism 32 in neutral, disconnecting the output path. The first coupling mechanism 31 controls the first spline 29 to engage with the fourth planetary carrier 23d, synchronizing the assembly housing 41 with the input shaft. Then, the control system controls the input shaft to rotate at low speed until the inlet of the lubrication channel 414 is precisely aligned with the oil supply position of the first oil channel 421. At this time, the first coupling mechanism locks the positions of the fourth planetary carrier 23d, the second planetary carrier 23b, and the third planetary carrier 23c, but the input shaft 11 is still rotating (i.e., the sun gear 21 and the third planetary gear 27 rotate on their own axis but not around the sun), allowing the lubricating oil to fully cover all positions of the meshing point of the sun gear 21 and the third planetary gear 27. Then, the oil pump 421a is started, and the lubricating oil is sprayed into the lubrication channel 414 through the first oil channel 421 and directly delivered to the meshing point of the sun gear 21 and the third planetary gear 27. After lubrication is completed, the system returns to its original gear position.

[0078] See attached document Figure 3 , Figure 4 , Figure 7 , Figure 8 , Figure 10 When the third planetary gear is engaged with the fourth planetary gear, the control system places the second coupling mechanism 32 in neutral, disconnecting the output path. The first coupling mechanism 31 controls the first spline 29 to engage with the fourth planetary carrier 23d, synchronizing the assembly housing 41 with the input shaft. Then, the input shaft is controlled to rotate at low speed until the opening of the planetary gear mounting part 413 is precisely aligned with the oil supply position of the first oil passage 421. At this time, the first coupling mechanism 31 locks the positions of the fourth planetary carrier 23d, the second planetary carrier 23b, and the third planetary carrier 23c (i.e., the assembly housing stops rotating), but the input shaft 11 continues to rotate (i.e., the third planetary gear 27 and the fourth planetary gear 28 rotate on their own axis but not around the sun), allowing the lubricating oil to fully cover all positions at the meshing points of the third planetary gear 27 and the fourth planetary gear 28. Then, the oil pump 421a is started, and the lubricating oil is sprayed into the planetary gear mounting part 413 through the first oil passage 421 and directly delivered to the meshing points of the third planetary gear 27 and the fourth planetary gear 28. After lubrication is completed, the system returns to its original gear position.

[0079] This embodiment combines structured lubrication channels with intelligent control to achieve precise lubrication of critical gear pairs without shutting down the system or disassembling it. It is particularly suitable for enhancing lubrication when the transmission oil level is insufficient under high load conditions. This system not only improves the reliability and durability of the transmission system but also reduces the risk of failures due to poor lubrication through condition monitoring and proactive control, demonstrating high engineering practical value.

[0080] The embodiments and / or implementation methods described above are merely preferred embodiments and / or implementation methods for implementing the technology of the present invention, and are not intended to limit the implementation methods of the technology of the present invention in any way. Any person skilled in the art may make some modifications to other equivalent embodiments without departing from the scope of the technical means disclosed in the content of the present invention, but these should still be regarded as the technology or embodiments that are substantially the same as the present invention. This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. The above descriptions are only preferred embodiments of this application. It should be noted that due to the limitations of written expression, while there are objectively infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of this application, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of this application.

Claims

1. A vehicle transmission, characterized in that, include: An input shaft (11) is mounted with a first spline (29) and a sun gear (21) for inputting torque; The output shaft (12) is equipped with a third spline (12a) for outputting torque; A planetary gear set (2) includes a sun gear (21), a ring gear (22) and a planet carrier (23), at least two planet gears being rotatably mounted on the planet carrier (23), the ring gear (22) and the sun gear (21) being configured to mesh with the at least one planet gear, and each planet carrier (23) being connected to a second spline (24). The first coupling mechanism (31) is used to achieve three selective connection states: fixing or rotatable the gear ring (22); fixing or revolving the planet carrier (23) around the sun gear (21); and engaging or disengaging the first spline (29) from the planet carrier (23). The second coupling mechanism (32) is used to selectively engage or disengage the third spline (12a) with one of the ring gear (22) or the second spline (24) of the planetary gear set (2).

2. The vehicle transmission according to claim 1, characterized in that, The planetary carrier (23) includes at least a first planetary carrier (23a), which is detachably connected to the second spline (24) and is provided with meshing teeth for meshing with the first spline (29).

3. The vehicle transmission according to claim 2, characterized in that, The first planet carrier (23a) is equipped with a first planet gear (25) and a second planet gear (26); When the first spline (29) engages with the first planetary carrier (23a), the first planetary carrier (23a) rotates under the drive of the first spline (29), and drives the second spline (24) to rotate.

4. The vehicle transmission according to claim 1, characterized in that, The planet carrier (23) includes at least a fourth planet carrier (23d), which has meshing teeth for meshing with the first spline (29), and is equipped with at least two second planet carriers (23b) and a third planet carrier (23c) that can rotate about their axes.

5. The vehicle transmission according to claim 4, characterized in that, The second planetary carrier (23b) is equipped with a third planetary gear (27), and the third planetary carrier (23c) is equipped with a fourth planetary gear (28). When the first spline (29) engages with the fourth planetary carrier (23d), the fourth planetary carrier (23d) rotates under the drive of the first spline (29), and drives the second spline (24) to rotate.

6. The vehicle transmission according to claim 5, characterized in that, It includes an assembly shell (41), which is a cylindrical structure with mounting holes (411) inside. The mounting holes (411) are used to install the second planetary carrier (23b) and the third planetary carrier (23c). The assembly housing (41) is also provided with a hollow hole (412), which is used to accommodate the sun gear (21) and provide space for the meshing of the sun gear (21) and the third planet gear (27); The assembly housing (41) is also provided with a planetary gear mounting part (413), which is used to provide a space for accommodating and engaging the third planetary gear (27) and the fourth planetary gear (28).

7. The vehicle transmission according to claim 6, characterized in that, The sidewall of the assembly housing (41) is provided with a lubrication channel (414), which leads directly from the periphery of the sidewall to the meshing point of the sun gear (21) and the third planet gear (27). The sidewall of the planetary gear mounting part (413) has a curved structure extending from the outer periphery to the inner wall, which is used to guide the lubricating oil to the meshing point of the third planetary gear (27) and the fourth planetary gear (28).

8. The vehicle transmission according to claim 6, characterized in that, The gearbox housing (42) includes a first oil passage (421) on which the outlet of the first oil passage (421) faces the gap between the assembly housing (41) and the gear ring (22), and the outlet of the first oil passage (421) is provided with an oil pump (421a).

9. The vehicle transmission according to claim 8, characterized in that, Also includes: A vision sensor, built into the transmission, is used to monitor the transmission status of each gear; The control system is connected to the external lubrication box, the first coupling mechanism (31) and the second coupling mechanism (32) respectively.

10. The vehicle transmission according to claim 9, characterized in that, The control system is configured to perform the following lubrication control: When it is detected that enhanced lubrication is needed for the sun gear (21) and the third planet gear (27), the second coupling mechanism (32) is switched to the neutral state, and the first spline (29) is driven to engage with the fourth planet carrier (23d) through the first coupling mechanism (31), so that the inlet of the lubrication channel (414) rotates and stops at the oil supply position corresponding to the outlet of the first oil channel (421). Then, the lubricating oil is released, so that the lubricating oil is delivered to the sun gear (21) and the third planet gear (27) through the lubrication channel (414) for lubrication. When it is detected that enhanced lubrication is needed for the third planetary gear (27) and the fourth planetary gear (28), the second coupling mechanism (32) is switched to neutral, and the first spline (29) is driven to engage with the fourth planetary carrier (23d) through the first coupling mechanism (31), so that the opening of the corresponding planetary gear mounting part (413) rotates and stops at the oil supply position corresponding to the outlet of the first oil passage (421). Then, the lubricating oil is released, so that the lubricating oil is delivered to the third planetary gear (27) and the fourth planetary gear (28) through the planetary gear mounting part (413) for lubrication.

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