Four-planet-wheel differential mechanism and vehicle with same

Abstract

The invention provides a four-planet-wheel differential mechanism and a vehicle with the same. The four-planet-wheel differential mechanism comprises a differential mechanism shell assembly, the differential mechanism shell assembly is provided with a mounting cavity, half shaft holes are formed in the two sides of the mounting cavity, and spiral groove structures are arranged on the hole walls of the half shaft holes; the half axle gear assembly comprises two half axle gears, a half axle gear installation face is arranged on the side, facing the half axle hole, of each half axle gear, a plurality of stepped oil guide grooves are formed between the half axle gear installation faces and the hole wall of the half axle hole, and the stepped oil guide grooves are evenly distributed in the circumferential direction of an installation cavity. An annular oil storage groove is formed in the differential shell assembly and arranged along the inner wall of the differential shell assembly, one end of each stepped oil guide groove communicates with the spiral groove structure, and the other end of each stepped oil guide groove communicates with the annular oil storage groove. A lubricating groove structure is further formed in the half axle gear mounting face, one end of the lubricating groove structure communicates with the annular oil storage groove, and the other end of the lubricating groove structure communicates with the planetary gear assembly.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of automobile transmission technology, in particular to a four-pinion differential and a vehicle with the same. BACKGROUND

[0002] In the field of differential technology, the traditional lubrication method mainly increases the spiral oil groove structure at the half shaft hole position of the shell and the oil groove structure at the half shaft gear end face of the shell, so as to introduce the lubricating oil at the bearing into the interior of the differential, in order to increase the lubrication between the internal parts. This method is acceptable in the differential with two-pinion structure, but in the differential with four-pinion structure, the internal space is more compact, resulting in poor lubrication effect.

[0003] In the four-pinion differential, only the oil inlet at the half shaft hole cannot meet the lubrication demand of the interior of the differential, especially during the limit differential and road test verification process. This problem leads to the aggravation of friction between the planet gear gasket and the differential shell, and the accumulation of heat due to insufficient lubrication, which eventually causes the gasket to ablate and the shell to wear severely.

[0004] In the traditional lubrication method, the oil is thrown into the interior of the differential by centrifugal force, which cannot ensure uniform distribution of the oil, especially in the area where the planet gear gasket contacts the differential shell. Uneven distribution of the oil will lead to poor local lubrication effect and aggravate wear.

[0005] With the operation of the differential, metal chips and other impurities will be generated in the interior. These impurities will mix into the lubricating oil, and the traditional lubrication method cannot effectively filter these impurities, resulting in reduced cleanliness of the oil and further aggravating the wear and ablation of the bevel gear gasket.

[0006] No effective solution has been proposed for the above problems. SUMMARY

[0007] The main purpose of the present application is to provide a four-pinion differential and a vehicle with the same, in order to solve the problem of insufficient gasket lubrication in the traditional differential, which leads to gasket wear and ablation.

[0008] In order to achieve the above object, according to one aspect of the present application, a four planetary wheel differential is provided, comprising: a differential housing assembly, the differential housing assembly having a mounting cavity, two sides of the mounting cavity being provided with half shaft holes, and a spiral groove structure being provided on the hole wall of the half shaft hole; a half shaft gear assembly, the half shaft gear assembly comprising: two half shaft gears, the half shaft gears being located in the mounting cavity; two half shafts, the two half shafts being provided in a one-to-one correspondence with the two half shaft holes, each half shaft being connected to the half shaft gear through a spline at one end located in the mounting cavity, and each half shaft being connected to a wheel at an end away from the mounting cavity, and each half shaft gear being provided with a half shaft gear mounting surface on a side facing the half shaft hole, a plurality of stepped oil guide grooves being provided between the half shaft gear mounting surface and the hole wall of the half shaft hole, and the plurality of stepped oil guide grooves being uniformly distributed along the circumference of the mounting cavity; a ring-shaped oil storage groove being provided in the differential housing assembly, the ring-shaped oil storage groove being provided along the inner wall of the differential housing assembly, and the ring-shaped oil storage groove being located on a side of the half shaft gear mounting surface close to the half shaft hole; one end of each of the stepped oil guide grooves being in communication with the spiral groove structure, and the other end of each of the stepped oil guide grooves being in communication with the ring-shaped oil storage groove; and a lubricating groove structure being further provided on the half shaft gear mounting surface, one end of the lubricating groove structure being in communication with the ring-shaped oil storage groove, and the other end of the lubricating groove structure being in communication with the planetary gear assembly.

[0009] Further, the spiral groove structure is spirally provided along the axis direction of the half shaft hole.

[0010] Further, the stepped oil guide groove is provided on the inner wall of the differential housing assembly, the stepped oil guide groove being provided extending towards the half shaft gear assembly along the axis direction of the half shaft hole, the stepped oil guide groove comprising: an inlet section, a first end of the inlet section being in communication with the end of the spiral groove structure, and the width dimension of the inlet section being correspondingly provided with the width dimension of the end of the spiral groove structure; a middle section, a first end of the middle section being in communication with a second end of the inlet section, a second end of the middle section being provided extending towards the half shaft gear assembly along the axis direction of the half shaft hole, and the width dimension of the middle section being greater than the width dimension of the inlet section; and an outlet section, a first end of the outlet section being in communication with a second end of the middle section, a second end of the outlet section being in communication with the ring-shaped oil storage groove, and the width dimension of the outlet section being less than the width dimension of the middle section.

[0011] Further, the length dimensions of the inlet section and the outlet section are consistent.

[0012] Further, four planetary gears are provided between the two half shaft gears, the four planetary gears being uniformly distributed along the circumference of the half shaft gear, each planetary gear being meshed with the two half shaft gears, and the two symmetrically arranged planetary gears being connected through a planetary gear shaft, the axis of the planetary gear shaft being perpendicular to the axis of the half shaft, and a planetary gear gasket being provided between each planetary gear and the inner wall of the differential housing assembly.

[0013] Further, one end of the lubricating groove structure away from the ring-shaped oil storage groove extends to the surface of the planetary gear gasket.

[0014] Further, the lubricating groove structure comprises a first lubricating groove, a second lubricating groove, a third lubricating groove and a fourth lubricating groove, and the first lubricating groove, the second lubricating groove, the third lubricating groove and the fourth lubricating groove are uniformly distributed along the circumference of the mounting cavity.

[0015] Further, at least one of the first lubricating groove, the second lubricating groove, the third lubricating groove and the fourth lubricating groove comprises a lubricating channel, the lubricating channel comprises a first lubricating channel and a second lubricating channel, the inlet of the first lubricating channel and the inlet of the second lubricating channel are connected, the outlet of the first lubricating channel and the outlet of the second lubricating channel are respectively arranged towards two adjacent planetary gears, and a mounting hole is arranged at the connection of the first lubricating channel and the second lubricating channel.

[0016] Further, a guide oil sheet is arranged in at least one of the first lubricating groove, the second lubricating groove, the third lubricating groove and the fourth lubricating groove, the guide oil sheet is arranged in the lubricating channel through the mounting hole, at least a part of the guide oil sheet is arranged in the first lubricating channel, and another part of the guide oil sheet is arranged in the second lubricating channel, wherein the guide oil sheet is a porous structure.

[0017] Further, the side of the guide oil sheet facing the differential housing assembly is in contact with the planetary gear gasket, and the side of the guide oil sheet facing the differential housing assembly is arranged as a reverse curved surface.

[0018] According to one aspect of the present application, a vehicle is provided, comprising a differential, which is the differential described above.

[0019] By applying the technical solution of the present application, the half shaft hole with a spiral groove structure is arranged at both ends of the differential housing assembly. The unique spiral groove design is combined with the hole wall of the half shaft hole, which can guide the lubricating oil into the interior of the differential by means of centrifugal force during the driving of the vehicle. In addition, a plurality of stepped oil guide grooves are arranged in the mounting cavity adjacent to the half shaft gear mounting surface, and the stepped oil guide grooves are uniformly distributed along the circumference. The stepped oil guide grooves not only increase the distribution range of the oil, but also store the lubricating oil and adjust the flow rate through the unique stepped structure. The annular oil storage groove serves as an important buffer and storage link, is located below the half shaft gear mounting surface and is connected to the other end of the stepped oil guide groove, and its function is to stabilize the oil pressure and provide lubricating oil storage. One end of the lubricating groove structure is connected to the annular oil storage groove, and the other end is in contact with the planetary gear assembly. Through this structure, the lubricating oil can be accurately delivered to the contact surface between the planetary gear assembly and the differential housing, forming an effective lubricating film, which significantly improves the uniformity of the lubrication efficiency and the lubrication effect. The lubricating system of the present application realizes the efficient and directional delivery and capillary penetration of the lubricating oil through the synergistic effect of the spiral groove, the stepped oil guide groove, the annular oil storage groove and the lubricating groove. The present application solves the problem of insufficient lubrication of the traditional differential gasket in the prior art, which leads to gasket wear and ablation. BRIEF DESCRIPTION OF DRAWINGS

[0020] The accompanying drawings, which form a part of this specification, are included to provide a further understanding of the application, and are incorporated herein by reference. The embodiments depicted herein are shown by way of example and not by way of limitation. In the drawings:

[0021] Figure 1 A structural schematic diagram of a first embodiment of the differential according to the present application is shown;

[0022] Figure 2 A structural schematic diagram of a second embodiment of the differential according to the present application is shown;

[0023] Figure 3 A structural schematic diagram of a third embodiment of the differential according to the present application is shown;

[0024] Figure 4 A structural schematic diagram of a fourth embodiment of the differential according to the present application is shown;

[0025] Figure 5 A structural schematic diagram of a fifth embodiment of the differential according to the present application is shown;

[0026] Figure 6 A structural schematic diagram of a sixth embodiment of the differential according to the present application is shown;

[0027] Figure 7 A structural schematic diagram of a seventh embodiment of the differential according to the present application is shown.

[0028] Wherein the above drawings include the following reference numerals:

[0029] 1. Differential housing assembly;

[0030] 2. Axle shaft hole; 20. Axle shaft gear;

[0031] 3. Axle shaft gear mating surface;

[0032] 4. Axle shaft gear mounting surface;

[0033] 5. First helical groove;

[0034] 6. Second helical groove;

[0035] 7. Annular oil reservoir;

[0036] 8. Oil deflector; 81. Oil film;

[0037] 9. Staged oil deflector; 901. Inlet section; 902. Intermediate section; 903. Outlet section;

[0038] 10. lubrication groove structure; 101. first lubrication groove; 102. second lubrication groove; 103. third lubrication groove; 104. fourth lubrication groove; 105. first lubrication passage; 106. second lubrication passage;

[0039] 11. mounting hole;

[0040] 12. end cap;

[0041] 13. planetary gear spacer;

[0042] 30. planetary gear;

[0043] 31. planetary gear shaft;

[0044] 200. window. DETAILED DESCRIPTION

[0045] It should be noted that the embodiments and features of the embodiments in the present application can be combined with each other without conflict. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0046] It should be noted that the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, the singular form is intended to include the plural form unless the context clearly indicates otherwise, and it should be understood that the use of the term "comprise" and / or "include" in this specification indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0047] It should be noted that the terms "first", "second", and the like in the description of the specification and claims of the present application and the above-described drawings are used to distinguish similar objects, and do not necessarily have to be used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchanged as appropriate, so that the embodiments of the present application described herein can be implemented, for example, in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device that includes a series of steps or units does not have to be limited to only those steps or units clearly listed, but can include other steps or units that are not clearly listed or inherent to such processes, methods, products or devices.

[0048] Now, exemplary embodiments according to this application will be described in greater detail by referring to the drawings. However, these exemplary embodiments can be implemented in various different forms, and should not be interpreted only as limiting to the embodiments set forth herein. It should be understood that these embodiments are provided in order to make the disclosure of this application thorough and complete, and to fully convey the concept of these exemplary embodiments to those having ordinary knowledge in the art, and in the drawings, in order to clarify, the thickness of layers and regions can be exaggerated, and the same reference numerals are used to denote the same elements, so that a description thereof will be omitted.

[0049] In combination Figures 1 to 7 As shown, according to specific embodiments of this application, a four planetary wheel differential is provided.

[0050] As Figure 1 shown, the four planetary wheel differential includes a differential housing assembly 1, the differential housing assembly 1 has a mounting cavity, both sides of the mounting cavity are provided with half shaft holes 2, and the hole wall of the half shaft hole 2 is provided with a spiral groove structure; a half shaft gear assembly, the half shaft gear assembly includes two half shaft gears 20, the half shaft gears are located in the mounting cavity; two half shafts are provided, the two half shafts are arranged one by one with the two half shaft holes 2, and one end of each half shaft located in the mounting cavity is connected with the half shaft gear 20 through a spline, and the other end of each half shaft away from the mounting cavity is connected with a wheel, and one side of each half shaft gear 20 facing the half shaft hole 2 is provided with a half shaft gear mounting surface 4, a plurality of stepped oil guide grooves 9 are arranged between the half shaft gear mounting surface 4 and the hole wall of the half shaft hole 2, and the plurality of stepped oil guide grooves 9 are uniformly distributed along the circumference of the mounting cavity; a ring-shaped oil storage groove 7 is opened in the differential housing assembly 1, the ring-shaped oil storage groove 7 is arranged along the inner wall of the differential housing assembly 1, and the ring-shaped oil storage groove 7 is located on one side of the half shaft gear mounting surface 4 close to the half shaft hole 2; one end of each stepped oil guide groove 9 is in communication with the spiral groove structure, and the other end of each stepped oil guide groove 9 is in communication with the ring-shaped oil storage groove 7; a lubricating groove structure 10 is also opened on the half shaft gear mounting surface 4, one end of the lubricating groove structure 10 is in communication with the ring-shaped oil storage groove 7, and the other end of the lubricating groove structure 10 is in communication with the planetary gear assembly.

[0051] Specifically, the oil injection nozzle opened on the reducer housing is directed to the joint of the half shaft and the differential half shaft hole, so that the oil enters the differential half shaft hole. When the reducer is running, the differential and the half shaft are in a rotating state, and the centrifugal force generated by the rotation of the differential and the half shaft guides the lubricating oil along the spiral groove structure towards the inside of the differential.

[0052] It should be further explained that in this scheme, four stepped oil guide grooves 9 are arranged along the circumference of the differential housing assembly (one every 90°), which ensures symmetrical oil delivery.

[0053] Specifically, the outer side of the half shaft hole 2 is provided with an end cover 12, and the end cover 12 is connected with the differential housing assembly 1.

[0054] Optionally, the inner wall of the differential housing assembly 1 and the half shaft gear 20 are further provided with a half shaft gear matching surface 3, and the half shaft gear matching surface 3 is located on the outer side of the stepped oil guide groove 9. The surface of the matching surface is finely processed to meet the required smoothness and roughness standards, thereby reducing the friction between the half shaft gear and the differential housing assembly 1.

[0055] By applying the technical scheme of the present application, the differential housing assembly 1 is provided with a half shaft hole 2 with a spiral groove structure at both ends. The unique spiral groove design combined with the hole wall of the half shaft hole 2 can guide the lubricating oil into the differential interior during vehicle driving by means of centrifugal force. In addition, a plurality of stepped oil guide grooves 9 are arranged in the installation cavity adjacent to the half shaft gear mounting surface 4, and these oil guide grooves are uniformly distributed in the circumferential direction, which not only increases the distribution range of the oil, but also buffers the lubricating oil and adjusts its flow rate through the unique stepped structure, and the annular oil storage groove 7 serves as an important buffer and storage link, located below the half shaft gear mounting surface 4 and connected with the other end of the stepped oil guide groove 9, which provides lubricating oil storage. The lubricating groove structure 10 is connected with the annular oil storage groove 7 at one end and contacts the planetary gear assembly at the other end, and through this structure, the lubricating oil can be accurately delivered to the contact surface of the planetary gear assembly and the differential housing, forming an effective lubricating film, which significantly improves the uniformity of lubrication efficiency and lubrication effect. The lubrication system of the present application realizes efficient directional delivery and capillary penetration of lubricating oil through the synergistic effect of spiral grooves, stepped oil guide grooves, annular oil storage grooves and lubricating grooves. The present application solves the problem of insufficient lubrication of the traditional differential pad in the prior art, which leads to pad wear and ablation.

[0056] Specifically, the spiral groove structure is spirally arranged along the axis direction of the half shaft hole 2. The spiral groove structure is spirally arranged along the axis direction of the half shaft hole 2, which effectively utilizes the centrifugal force generated in the rotary motion to promote the lubricating oil to enter the differential interior along the spiral path smoothly.

[0057] In this embodiment, the spiral groove structure includes first spiral grooves 5 and second spiral grooves 6, and the first spiral grooves 5 and the second spiral grooves 6 are alternately distributed on the hole wall of the half shaft hole 2, wherein the groove widths of the first spiral grooves 5 and the second spiral grooves 6 are consistent, and the stepped oil guide grooves 9 are arranged in communication with the first spiral grooves 5 or the second spiral grooves 6. The spiral groove structure includes first spiral grooves 5 and second spiral grooves 6, which together constitute the lubrication guide channel on the inner wall of the half shaft hole 2 at both ends of the differential housing. The spiral groove design utilizes the centrifugal force inside the differential during vehicle driving to make the lubricating oil flow along the spiral path from the outside of the half shaft hole to the inside of the differential, so as to ensure that the lubricating oil can cover a wider range of components.

[0058] The consistency of the groove width of the first spiral groove 5 and the second spiral groove 6 also ensures the stability of the lubricating oil flow, avoiding the flow rate changes caused by different widths, thereby affecting the lubrication effect.

[0059] The stepped oil guide groove 9 is arranged in communication with the first spiral groove 5 or the second spiral groove 6, which means that after entering from the spiral groove structure, the lubricating oil will be further guided into the stepped oil guide groove. The function of the stepped oil guide groove is to adjust the flow rate and flow direction of the lubricating oil, so as to ensure that it can flow gently and uniformly to the key components inside the differential, such as the contact surface between the differential housing and the half shaft gear, and the planet gear gasket, etc.

[0060] Specifically, the stepped oil guide groove 9 is arranged on the inner wall of the differential housing assembly 1 and extends along the axis direction of the half shaft hole 2 towards the half shaft gear assembly. The stepped oil guide groove 9 comprises: an inlet section 901, the first end of the inlet section 901 is in communication with the end of the spiral groove structure, and the width dimension of the inlet section 901 is correspondingly arranged with the width dimension of the end of the spiral groove structure; an intermediate section 902, the first end of the intermediate section 902 is arranged in communication with the second end of the inlet section 901, the second end of the intermediate section 902 extends along the axis direction of the half shaft hole 2 towards the half shaft gear assembly, and the width dimension of the intermediate section 902 is greater than the width dimension of the inlet section 901; an outlet section 903, the first end of the outlet section 903 is arranged in communication with the second end of the intermediate section 902, and the second end of the outlet section 903 is arranged in communication with the annular oil storage groove 7, and the width dimension of the outlet section 903 is less than the width dimension of the intermediate section 902.

[0061] The inlet section 901 is in communication with the end of the spiral groove structure, that is, when the lubricating oil is guided into the differential through the spiral groove structure, it will first enter the inlet section 901. The width dimension of the inlet section 901 matches the end of the spiral groove, which can seamlessly transition and avoid turbulence or leakage of the oil when entering the oil guide groove, ensuring the continuity and stability of the lubricating oil flow.

[0062] The width of the intermediate section 902 is greater than that of the inlet section 901, which helps to increase the storage capacity of the lubricating oil. At the same time, the larger width can also reduce the flow rate of the oil, reducing the impact and wear that the oil may cause to the parts when flowing at high speed. The second end of the intermediate section 902 continues to extend along the axis direction of the half shaft hole 2 towards the half shaft gear assembly, which is to more accurately guide the lubricating oil to the planetary gear assembly.

[0063] The width of the outlet section 903 is designed to be smaller than that of the intermediate section 902, and this narrow outlet section is conducive to forming a certain pressure difference. The second end of the outlet section 903 is in communication with the annular oil storage groove 7 to guide the lubricating oil into the annular oil storage groove 7.

[0064] In a specific embodiment, the stepped oil guide groove 9 is formed by the cylindrical surface of the half shaft gear and the surface of the half shaft gear washer. When the differential is in operation, lubricating oil is forced by centrifugal force to flow from the end of the spiral groove structure to the entrance section 901, and then to the middle section 902 with a larger width. Here, the flow rate of the lubricating oil is significantly slowed down, which helps the oil transition smoothly and reduces turbulence, while also facilitating the sedimentation of larger particulate impurities in the lubricating oil, thereby improving the cleanliness of the oil. The lubricating oil then enters the exit section 903, where the narrower width causes the oil to form a certain pressure, accelerating the penetration of the oil to the friction interface. The lubricating oil flows along the exit section 903 to the annular oil reservoir 7, and also partially penetrates the half shaft gear assembly to reduce friction and improve efficiency. The communication between the exit section 903 and the annular oil reservoir 7 enables the recycling of oil, with excess lubricating oil or oil that has completed lubrication being able to flow back to the reservoir for use in the next cycle. The design of the annular oil reservoir 7 also provides additional storage space for lubricating oil, maintaining the stable operation of the lubrication system.

[0065] Specifically, the length of the entrance section 901 and the exit section 903 is the same. The same length of the entrance section 901 and the exit section 903 means that there is no sudden change in length in the path of the lubricating oil from entering the oil guide groove to finally flowing out to the annular oil reservoir 7, which helps to maintain the uniformity and stability of the lubricating oil flow, preventing unnecessary vortex or stagnation when flowing through different length sections, and ensuring that the lubricating oil can be smoothly and unobstructed to the various contact surfaces that need to be lubricated.

[0066] By setting the same length of the entrance section 901 and the exit section 903, the flow rate of the lubricating oil can be controlled to some extent. Due to the smaller width of the exit section 903, the flow rate of the lubricating oil in the exit section 903 will be higher than that in the entrance section 901 under the same length condition. This change in flow rate helps the lubricating oil to form a proper "extrusion" effect in the exit section, promoting the penetration of the lubricating oil to the contact surface, while also limiting the excessive amount of lubricating oil from being discharged at once, avoiding waste and potential leakage risks.

[0067] In the design of the stepped oil guide groove, the depth of each step is consistent, which can ensure that the buffer volume of the entire oil guide groove is continuous and uniform. The consistent depth of the steps can maintain consistent oil contact area and fluid dynamic properties throughout the flow path, helping to form a stable flow state of the lubricating oil inside the oil guide groove, reducing flow resistance, and improving lubrication efficiency.

[0068] Specifically, four planetary gears 30 are provided between the two half axle gears 20, and the four planetary gears 30 are uniformly distributed along the circumference of the half axle gears 20. Each planetary gear 30 is in meshing arrangement with the two half axle gears 20, and the two symmetrically arranged planetary gears 30 are connected by a planetary gear shaft 31. The axis of the planetary gear shaft 31 is arranged perpendicularly to the axis of the half axle. A planetary gear gasket 13 is provided between each planetary gear 30 and the inner wall of the differential housing assembly 1.

[0069] Optionally, the two half axles are respectively connected to the left and right wheels of the vehicle. When the vehicle is driving in a straight line, the speeds of the two wheels are approximately the same, so that the half axle gears can stably receive and transmit torque from the transmission shaft through meshing with the planetary gears 30. At this time, the four planetary gears 30 hardly rotate and only rotate with the differential housing assembly 1. When the vehicle is turning or the rolling resistance of one side of the wheel increases (such as wet or muddy road), the speeds of the two wheels will be different. At this time, the planetary gears 30 start to rotate in the differential housing assembly due to the meshing relationship with the half axle gears, thereby changing the distribution ratio of the torque and allowing the two wheels to rotate at different speeds. This self-rotation action is achieved through the meshing of the planetary gears and the half axle gears, ensuring that the torque can be flexibly distributed between the two wheels as needed.

[0070] In the present embodiment, as shown in Figure 6 、 Figure 7 , the two symmetrically arranged planetary gears 30 are connected by a planetary gear shaft 31, and the axis of the shaft is arranged perpendicularly to the axis of the half axle. This perpendicular layout design ensures the rational use of space inside the differential housing assembly 1, and at the same time, the vertical planetary gear shaft helps to stabilize the planetary gears when they are subjected to torque, reducing the possibility of axial displacement and thus reducing wear and vibration.

[0071] In another embodiment, the four planetary gears can have four planetary gear shafts, and the ends of the four planetary gear shafts away from the planetary gears are connected to a point.

[0072] The planetary gear gasket 13 is located between the planetary gears and the housing, which can significantly reduce the friction coefficient when the two are in direct contact, reduce the wear rate, and prolong the service life of the differential. The gasket also has a certain sealing effect, preventing the leakage of lubricating oil inside the differential, ensuring the integrity of the lubrication system. At the same time, it forms a lubricating layer by contacting the lubricating oil, improving the lubrication effect.

[0073] Specifically, the lubrication groove structure 10 extends to the surface of the planetary gear gasket 13 away from one end of the annular oil reservoir 7. During the operation of the differential, high friction will occur between the planetary gear gasket 13 and the differential housing and the planetary gears 30, especially when the vehicle is turning or driving on uneven road surfaces. This friction can cause the gasket temperature to rise, accelerate wear, and potentially cause material fatigue and failure. Therefore, the design of the lubrication groove structure 10 aims to precisely control the flow of lubricating oil to ensure that it can directly contact the surface of the planetary gear gasket 13, forming a uniform and stable lubricating film to reduce friction and wear, prolong the service life of the gasket, and help cool and reduce thermal stress. The direct contact between the lubrication groove structure 10 and the planetary gear gasket 13 allows the lubricating oil to quickly reach the friction surface without the need for complex paths or additional delivery mechanisms, greatly improving lubrication efficiency. In addition, due to the direct supply of lubricant, the loss of lubricant during delivery can be reduced, ensuring effective use of the lubricant.

[0074] Specifically, the lubrication groove structure 10 includes a first lubrication groove 101, a second lubrication groove 102, a third lubrication groove 103, and a fourth lubrication groove 104, which are evenly distributed along the circumference of the mounting cavity.

[0075] By evenly arranging the lubrication grooves in the circumference of the differential housing, the oil can more smoothly enter the contact area of each planetary gear under the action of centrifugal force after reaching the stepped oil guide groove, forming a stable lubricating oil film, thereby significantly enhancing the lubrication effect, reducing friction loss, and prolonging the service life of the components inside the differential. In addition, the uniform distribution of the lubrication grooves helps to control the flow of oil, preventing excessive oil from accumulating in a certain area and causing waste, and achieving effective management and recycling of oil.

[0076] Traditional differential lubrication systems often rely on the free flow or passive diffusion of lubricating oil. This method is difficult to ensure uniform coverage and stable supply of lubricating oil under high-low speed changes or large load changes, which can easily lead to insufficient lubrication in some areas and accelerate material wear. The lubrication groove structure 10 in this embodiment actively controls the directional delivery of lubricating oil, solving the problem of uneven lubrication and low efficiency that occurs in traditional lubrication methods under complex working conditions.

[0077] Specifically, at least one of the first lubricating groove 101, the second lubricating groove 102, the third lubricating groove 103 and the fourth lubricating groove 104 comprises a lubricating channel, which comprises a first lubricating channel 105 and a second lubricating channel 106, the inlets of the first lubricating channel 105 and the second lubricating channel 106 are connected, the outlets of the first lubricating channel 105 and the second lubricating channel 106 are respectively arranged towards the adjacent two planetary gears 30, and the connection of the first lubricating channel 105 and the second lubricating channel 106 is provided with the mounting hole 11. By connecting the inlets of the first lubricating channel 105 and the second lubricating channel 106 to the annular oil storage groove 7, while ensuring that the respective outlets are respectively arranged towards the adjacent two planetary gears, the lubricating oil can be distributed to each planetary gear and its contact surface in a targeted manner, forming a uniform and stable lubricating film, reducing friction, improving efficiency and prolonging the service life of the differential.

[0078] In the embodiment, the first lubricating groove 101, the second lubricating groove 102, the third lubricating groove 103 and the fourth lubricating groove 104 are independent of each other but connected through the annular oil storage groove 7.

[0079] Specifically, at least one of the first lubricating groove 101, the second lubricating groove 102, the third lubricating groove 103 and the fourth lubricating groove 104 is provided with an oil guide sheet 8, the oil guide sheet 8 is mounted in the lubricating channel through the mounting hole 11, at least a part of the oil guide sheet 8 is located in the first lubricating channel 105, and another part of the oil guide sheet 8 is located in the second lubricating channel 106, wherein the oil guide sheet 8 is of a porous structure.

[0080] The porous property of the oil guide sheet 8 enables it to absorb and store a large amount of lubricating oil. When the lubricating oil in the lubricating groove contacts the oil guide sheet, the lubricating oil is attracted by the pores, forming a concave liquid surface and generating a capillary pressure difference, which promotes the penetration of the lubricating oil from the surface to the interior of the material until the entire oil guide sheet is saturated with the lubricating oil.

[0081] Once the oil guide sheet 8 is saturated with the lubricating oil, it will be driven by the capillary force to direct the lubricating oil to the contact surface between the planetary gear gasket 13 and the inner wall of the differential housing assembly 1, forming an oil film 81. At the same time, the porous structure of the oil guide sheet 8 can also filter impurities in the lubricating oil, keeping the lubricating effect clean and efficient.

[0082] Capillary phenomenon refers to the spontaneous rising or falling of a liquid in narrow pores or small tube channels, which is mainly determined by the surface tension of the liquid and the size of the pores or channels. When the lubricating oil contacts the surface of the oil guide sheet, its surface tension causes the oil to form a concave liquid surface, which generates a small pressure difference near the pores of the oil guide sheet, i.e. capillary pressure difference. This pressure difference becomes the driving force for the lubricating oil to enter the internal pores of the oil guide sheet until the entire oil guide sheet is completely wetted with the oil, forming a saturated "oil sponge".

[0083] In the present application, the oil guide sheet is installed in the grooves connected to the annular oil reservoir 7, which extend to the planetary gear spherical contact area. Therefore, when the planetary gear starts to rotate and interacts with the half shaft gear, the lubricating oil in the oil guide sheet will migrate to the contact surface between the planetary gear gasket and the differential housing along the preset path under the driving of capillary force, forming a stable lubricating oil film, reducing friction, and improving lubrication efficiency.

[0084] The installation hole 11 serves to securely install the oil guide sheet 8 in the lubrication channel, ensuring that it can maintain the correct position and shape during the operation of the differential, avoiding displacement due to vehicle vibration or high-speed rotation, which affects the lubrication effect. In this embodiment, the design of the installation hole 11 also takes into account the convenience of later maintenance and replacement of the oil guide sheet 8. Through appropriate fixing devices (such as three-jaw buckles), the oil guide sheet can be easily removed and replaced without damaging the structure of the differential, simplifying the maintenance process.

[0085] The oil guide sheet 8 is divided into two parts, located in the first lubrication channel 105 and the second lubrication channel 106 respectively. Such a layout ensures that the lubricating oil can be evenly distributed to the contact points between the two adjacent planetary gears 30, thereby achieving effective lubrication of the entire differential internal friction points. By setting the oil guide sheet 8 in the first lubrication channel 105 and the second lubrication channel 106, the lubrication efficiency and uniformity can be significantly improved. This is because the porous structure of the oil guide sheet not only can quickly absorb lubricating oil, but also can stably and uniformly deliver lubricating oil to the surface of the planetary gear gasket 13 through capillary action without external pumping equipment, forming a thin lubricating film, reducing the friction coefficient, and improving the operating efficiency and life of the differential. Due to the efficient distribution and utilization of lubricating oil, unnecessary oil consumption and energy loss are reduced, thereby improving the energy utilization efficiency of the differential and even the entire vehicle to a certain extent.

[0086] In the prior art, the traditional differential lubrication method often relies on the free flow or passive diffusion of lubricating oil, which is difficult to ensure uniform lubrication of each friction point under complex working conditions, and is prone to local lubrication deficiency and increased wear. In contrast, the design of the oil guide sheet 8 in the lubrication groove in this embodiment not only overcomes the limitations of traditional lubrication methods, but also innovatively uses capillary phenomenon to improve the accuracy and efficiency of lubrication.

[0087] In this embodiment, the shape of the oil guide sheet 8 corresponds to the shape of the lubrication channel. The oil guide sheet 8 is made of elastic material, and when the oil guide sheet 8 is installed in the lubrication channel, it can be fixed to the plastic or fixing part that matches its structure, facilitating the extension of the oil guide sheet into the first lubrication channel 105 and the second lubrication channel 106.

[0088] Specifically, asFigure 5 As shown, the side of the oil guide 8 facing the differential housing assembly 1 is in contact with the planet gear shim 13, and the side of the oil guide 8 facing the differential housing assembly 1 is designed as a reverse curve. The design of the reverse curve can better fit the profile of the planet gear shim 13, especially when the shim rotates with the planet gear at high speed, it can form a closer contact, ensuring that the gap between the oil guide and the shim is minimized, thereby improving the transmission efficiency of the lubricating oil.

[0089] Due to the capillary action of the oil guide 8, the oil is quickly sucked in and released through its internal network to the contact surface of the planet gear shim 13. The reverse curve contact form not only promotes uniform distribution of oil, but also maintains a stable oil film thickness when the planet gear shim 13 rotates, effectively reducing wear and tear, reducing friction temperature rise, and improving lubrication efficiency. In addition, the design of the reverse curve is also conducive to the circulation of oil between the oil guide 8 and the planet gear shim 13, which can maintain good lubrication effect even under high-speed rotating conditions, ensuring that the differential assembly can be adequately lubricated under various working conditions, prolonging the service life of the differential.

[0090] The main contact area of the planet gear shim 13 is usually located within about 60% of the center of the shim outward. This area is called the "main contact area" because under normal operating conditions, the force of the planet gear in contact with the shim is mainly concentrated in this part, especially when turning or load changes, this area bears more pressure and friction than other areas of the shim. The surface of the oil guide 8 is designed as a reverse curve, and the purpose of this special shape is to better fit the main contact area of the planet gear shim 13. This design allows the oil guide 8 to first deliver lubricating oil to the high-load area of the planet gear shim 13, i.e. the main contact area, during differential operation. Through capillary effect, lubricating oil can form a stable oil film in this area, greatly reducing friction and protecting the shim from wear. In other embodiments, the reverse curve of the oil guide 8 can be adjusted to different curvatures to accommodate planet gear shims 13 of different sizes or shapes, thereby achieving wider applicability. The oil guide 8 can suck oil from the annular oil reservoir 7 under the action of capillary force, which is the cornerstone of the lubrication system cycle in this invention. When the lubricating oil is attracted through the pores of the oil guide, a stable oil path from the lubricating groove to the friction pair is formed. This oil path not only provides the basic amount of oil required for lubrication, but also ensures continuous replenishment of lubricating oil under high temperature and high load conditions, forming a closed and efficient circulation system.

[0091] It is further noted that during operation, the oil wiper 8 is stimulated by the load forces generated by the friction pair, particularly the contact pressure between the planet gear shim and the housing. This stimulation encourages the steady release of lubricating grease within the oil wiper, ensuring a continuous supply of lubricating oil. At the same time, the reverse curvature design of the oil wiper also helps to distribute this load force, reducing the likelihood of local overloading and further ensuring the stability of the lubrication effect. In the process of absorbing and releasing lubricating oil, the oil wiper also plays a role in heat energy management. The released lubricating oil will carry away the heat generated by friction, reducing the surface temperature of the friction pair, thereby reducing additional wear and damage caused by high temperature and prolonging the service life of the differential. The released lubricating oil will be evenly distributed on the entire half shaft gear mounting surface 4 as the planet gear shim 13 rotates. This coverage not only protects the friction surface between the half shaft gear and the shim, but also significantly reduces the friction coefficient through the formation of an oil film, improving transmission efficiency. Excess lubricating oil will flow out through the housing window 200, and this mechanism prevents excessive accumulation of oil inside the differential, avoiding possible oil blockage and reduced pumping efficiency. By effectively managing excess oil, the cleanliness and health of the differential internal lubrication environment are ensured, reducing maintenance frequency.

[0092] According to an aspect of the present application, a vehicle is provided, comprising a differential, which is the differential of the above-mentioned embodiments.

[0093] When the vehicle starts, the reducer begins to work, and the lubricating oil is introduced through the spiral groove structure at the half shaft hole of the differential housing. With the high-speed rotation of the differential housing and the half shaft gear assembly, the lubricating oil is affected by centrifugal force and flows along the path of the spiral groove, reaching the stepped oil guide groove between the half shaft gear mounting surface and the half shaft hole wall. The unique geometric design of the stepped oil guide groove slows down the flow speed of the oil, increases the contact time with the half shaft gear and the gasket, and evenly distributes and fully covers the contact surface with lubricating oil, improving the lubrication efficiency. Then, the lubricating oil enters the annular oil storage groove at the end of the stepped oil guide groove, which is located below the half shaft gear mounting surface, increasing the storage capacity of the oil and maintaining a continuous and stable lubrication supply. Between the annular oil storage groove and the half shaft gear mounting surface, a lubrication groove structure is provided, including first to fourth lubrication grooves, which are evenly distributed along the circumference of the differential housing, ensuring that the lubricating oil is evenly distributed to each planetary gear gasket. After reaching the lubrication groove, the lubricating oil flows through the oil guide sheet made of porous material, which absorbs oil through its capillary network and then releases lubricating oil to the contact surface under the action of centrifugal force and pressure when the planetary gear gasket rotates, forming an effective oil film, reducing friction, reducing temperature rise, and avoiding gasket ablation. The porous structure of the oil guide sheet also plays a role in filtering impurities, improving the cleanliness of the lubricating oil, thereby enhancing the lubrication effect and prolonging the service life of the differential assembly. The entire lubrication process, from the initial oil supply of the spiral groove structure, to the oil storage and guidance of the stepped oil guide groove, to the directional capillary penetration of the oil guide sheet, forms a closed-loop lubrication system that effectively improves the lubrication conditions inside the four planetary wheel differential, ensuring the continuous and stable operation and long-term durability of the differential under complex working conditions. During vehicle operation, the lubrication system can work continuously, even under high-speed or load-changing conditions, and the differential inside can still maintain an ideal lubrication state, significantly improving the smoothness and safety of vehicle operation. After the lubricating oil completes the lubrication task, the excess oil will flow back to the differential housing oil pool along the planetary gear spherical surface, forming a good circulation, thereby avoiding waste of lubricating oil and maintaining a clean environment inside the differential. The efficiency and precision of the entire lubrication process provide strong support for the long-term and stable operation of the four planetary wheel differential.

[0094] For purposes of the description hereinafter, the terms "upper", "lower", "right", "left", "rear", "front", "vertical", "horizontal", and derivatives thereof (e.g., "vertical ly", "horizontal ly", etc.) can refer to the relative positions of an apparatus or feature as shown in the drawings, and shall not be construed as limiting the present application to any particular spatial orientation. Furthermore, the terms "first", "second", third", etc. merely identify one of a number of similar features or steps in an embodiment, and are not intended to denote a spatial or chronological priority of such features or steps to one another. The terms "comprise", "comprising", "include", "including", and the like, as used herein, are specifically intended to be construed as open-ended terms (i.e., the terms do not exclude the presence of other elements or steps). It is specifically intended that any total number or range of steps or components to be

[0095] In addition, it should be understood that any numerical range recited herein includes all values from the lower and upper limits of that range. For example, if a concentration range is stated as 1% to 50%, it is intended that values ranging from 1% to 50%, such as 20%, are expressly enumerated. It is also understood that the endpoints of the ranges are not significant and are intended to be merely approximate. It is also understood that the description is not intended to be limited to the precise forms disclosed. Many modifications and variations are possible in light of the above teachings.

[0096] In the above embodiments, the description of each embodiment focuses on different aspects, and the parts not described in detail in a certain embodiment can be referred to the relevant description of other embodiments.

[0097] The preferred embodiments of the present application have been described above with the aid of drawing figures, which are intended to be illustrative only and not restrictive of the application. It will be apparent to those skilled in the art that modifications, improvements and variations of the application can be made without departing from the spirit and scope of the application.

Claims

1. A four planetary wheel differential characterized in that, The application relates to a differential housing assembly (1) comprising: a differential housing assembly (1) having a mounting cavity, two half shaft holes (2) being arranged on two sides of the mounting cavity, and a spiral groove structure being arranged on a hole wall of the half shaft hole (2); a half shaft gear assembly comprising two half shaft gears (20) arranged in the mounting cavity; two half shafts, each of which is arranged in correspondence with one of the half shaft holes (2), and each of which is connected with the half shaft gear (20) through a spline at one end in the mounting cavity, and each of which is connected with a wheel at an end away from the mounting cavity, and each of the half shaft gears (20) is provided with a half shaft gear mounting surface (4) on a side facing the half shaft hole (2), and a plurality of stepped oil guide grooves (9) are arranged between the half shaft gear mounting surface (4) and the hole wall of the half shaft hole (2), and the plurality of stepped oil guide grooves (9) are uniformly distributed along the circumference of the mounting cavity; an annular oil storage groove (7) is arranged in the differential housing assembly (1) along an inner wall of the differential housing assembly (1), and the annular oil storage groove (7) is arranged on a side of the half shaft gear mounting surface (4) close to the half shaft hole (2); one end of each of the stepped oil guide grooves (9) is in communication with the spiral groove structure, and the other end of each of the stepped oil guide grooves (9) is in communication with the annular oil storage groove (7); a lubricating groove structure (10) is further arranged on the half shaft gear mounting surface (4), one end of the lubricating groove structure (10) is in communication with the annular oil storage groove (7), and the other end of the lubricating groove structure (10) is in communication with a planetary gear assembly.

2. The four-planetary wheel differential according to claim 1, wherein, The spiral groove structure is spirally arranged along the axis direction of the half shaft hole (2).

3. The differential according to claim 1 or 2, characterized in that The stepped oil guide groove (9) is arranged on the inner wall of the differential housing assembly (1), and the stepped oil guide groove (9) is arranged in an extending direction along the axis of the half shaft hole (2) towards the half shaft gear assembly, and the stepped oil guide groove (9) comprises: an inlet section (901), a first end of the inlet section (901) is in communication with the end of the spiral groove structure, and the width dimension of the inlet section (901) is arranged in correspondence with the width dimension of the end of the spiral groove structure; a middle section (902), a first end of the middle section (902) is in communication with a second end of the inlet section (901), a second end of the middle section (902) is arranged in an extending direction along the axis of the half shaft hole (2) towards the half shaft gear assembly, and the width dimension of the middle section (902) is greater than the width dimension of the inlet section (901); an outlet section (903), a first end of the outlet section (903) is in communication with a second end of the middle section (902), a second end of the outlet section (903) is in communication with the annular oil storage groove (7), and the width dimension of the outlet section (903) is smaller than the width dimension of the middle section (902).

4. The differential of claim 3 wherein, The length dimensions of the inlet section (901) and the outlet section (903) are consistent.

5. The differential of claim 1, wherein, Four planetary gears (30) are arranged between the two half axle gears (20), the four planetary gears (30) are uniformly distributed along the circumference of the half axle gear (20), each of the planetary gears (30) is arranged in meshing with two half axle gears (20), the two planetary gears (30) arranged symmetrically are connected through a planetary gear shaft (31), the axis of the planetary gear shaft (31) is arranged perpendicularly to the axis of the half axle, and a planetary gear gasket (13) is arranged between each of the planetary gears (30) and the inner wall of the differential housing assembly (1).

6. The differential of claim 5 wherein, The lubrication groove structure (10) extends to the surface of the planetary gear gasket (13) away from one end of the annular oil storage groove (7).

7. The differential of claim 6 wherein, The lubrication groove structure (10) comprises a first lubrication groove (101), a second lubrication groove (102), a third lubrication groove (103) and a fourth lubrication groove (104), and the first lubrication groove (101), the second lubrication groove (102), the third lubrication groove (103) and the fourth lubrication groove (104) are uniformly distributed along the circumference of the mounting cavity.

8. The differential of claim 7, wherein, At least one of the first lubrication groove (101), the second lubrication groove (102), the third lubrication groove (103) and the fourth lubrication groove (104) comprises a lubrication channel, the lubrication channel comprises a first lubrication channel (105) and a second lubrication channel (106), the inlet of the first lubrication channel (105) and the second lubrication channel (106) are connected, the outlet of the first lubrication channel (105) and the second lubrication channel (106) are arranged towards two adjacent planetary gears (30) respectively, and a mounting hole (11) is arranged at the connection of the first lubrication channel (105) and the second lubrication channel (106).

9. The differential of claim 8, wherein, At least one of the first lubrication groove (101), the second lubrication groove (102), the third lubrication groove (103) and the fourth lubrication groove (104) is provided with an oil guide sheet (8), the oil guide sheet (8) is mounted in the lubrication channel through the mounting hole (11), at least a part of the oil guide sheet (8) is located in the first lubrication channel (105), and another part of the oil guide sheet (8) is located in the second lubrication channel (106), wherein the oil guide sheet (8) is a porous structure.

10. The differential of claim 9, wherein, One side of the oil guide sheet (8) facing the differential housing assembly (1) is in contact with the planetary gear gasket (13), and the one side of the oil guide sheet (8) facing the differential housing assembly (1) is provided as a reverse curve surface.

11. A vehicle comprising a differential, characterized in that The differential is the differential of any one of claims 1-10.

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