A reducer shell wall and reducer imitating convex structure of a bionic scarab beetle

Abstract

The application relates to the technical field of reducer housings and discloses a reducer housing wall with a bionic scarab surface convex bump structure and a reducer, which comprises a reducer housing; a convex bump array structure formed by a plurality of ellipsoid hollow convex bumps of a bionic scarab prothoracic notum is integrally formed on a local or global inner wall of the reducer housing; the convex bump array structure formed by the plurality of ellipsoid hollow convex bumps is arranged in an odd-even row staggered mode; a gap groove is arranged between every two adjacent ellipsoid hollow convex bumps on the inner wall of the reducer housing, and the gap groove forms an air micro-cavity between the ellipsoid hollow convex bumps; the bionic scarab non-smooth surface anti-viscosity resistance covering mechanism cuts off the continuous wall-attached oil film on the inner wall of the housing by means of the convex bump array, greatly reduces the effective contact area of lubricating oil and the housing wall surface, breaks large oil droplets flying at high speed, and accelerates the quick backflow of oil liquid to an oil pool through the micro-flow guiding groove, so that the problems of oil stirring loss, oil liquid gas entrainment, housing temperature rise and exhaust oil seepage under high-speed working conditions are effectively inhibited.

Description

Technical Field

[0001] This invention relates to the field of reducer housing technology, and in particular to a reducer housing wall and reducer with a biomimetic dung beetle surface convex structure. Background Technology

[0002] The housing of common reducers is cast as a whole, with the inner wall of the housing being a complete, continuous, smooth plane / curved surface without any protrusions, grooves, or biomimetic structures. It relies solely on oil storage in the oil sump at the bottom of the housing and gear splash lubrication, without any internal oil flow constraint structure. The exhaust plug is simply a straight hole ventilation structure without any matching oil baffle protection structure. It is widely used in traditional industrial low-speed reducers and old passenger car reducers.

[0003] The problems with the aforementioned reducer inner shell structure are as follows: 1. In reducers with a continuously smooth inner shell, the lubricating oil ejected at high speed by the gears adheres completely to the wall surface, forming a large-area continuous lubricating oil film. This results in a large solid-liquid contact area and extremely high viscous shear resistance. Without a structure to break up oil droplets and trap air, the high-speed oil droplets continuously impact the wall surface, creating a swirling motion and causing significant power loss during swirling. Under high-speed operating conditions, a large amount of energy is consumed by the lubricating oil's agitation, leading to a low overall transmission efficiency and an inability to meet the energy-saving requirements of new energy equipment. 2. Without a buffer structure on the smooth wall surface, the high-speed oil flow directly and rigidly impacts the shell, generating strong turbulent vortices that continuously entrain air from outside the shell into the lubricating oil, forming a large number of free bubbles and surface foam (air entrainment / aeration). These bubbles have extremely poor thermal conductivity, significantly reducing the shell's heat dissipation efficiency and significantly increasing the steady-state operating temperature. High temperatures accelerate the oxidation and aging of the lubricating oil, reducing the oil film's load-bearing capacity, and making gears and bearings prone to dry friction and sparking. 3. The continuous agitation of gears causes the oil temperature and internal air pressure in the gearbox to rise. The splashed oil can directly impact the exhaust plug without any obstruction. Under the action of pressure difference, the oil seeps out along the exhaust hole. There is no special oil barrier, and high and low speed conditions cannot be taken into account. The high-speed leakage problem cannot be completely solved, which easily leads to lubricating oil waste and environmental pollution. In severe cases, oil shortage will cause transmission failure. 4. There is no drag reduction structure in the high-speed impact area, and the problems of oil agitation and air entrapment are prominent. There is no flow guiding structure in the bottom oil pool area. At low speed idling, splashed oil sticks to the wall and stagnates. The return speed is slow, and the lubrication supply to bearings and gear meshing pairs is insufficient. The versatility of high and low speed, heavy load and light weight scenarios is poor. 5. The smooth inner wall oil and impurities are washed by high speed for a long time, which forms uniform wear. The roughness of the inner wall of the shell continues to deteriorate with long-term operation, which further aggravates oil adhesion and oil agitation loss. There is no stress dispersion structure. The impact force generated by the oil flow impact is concentrated on the local shell wall.

[0004] To address the aforementioned issues, an improved solution has emerged. The reducer housing structure, based on the smooth inner wall of the housing, is further reinforced with separate components such as independent oil baffles, oil baffle ribs, oil baffle rings, and flow dividers. These components are fixed to the inner wall of the housing, bearing seats, and around the exhaust plug using bolts and clips. The solid baffles physically shield against splashing oil. The housing and the oil baffle components are two independent sets of components, machined and assembled separately. This is currently a common improvement solution for reducers in new energy, aviation, and medium-to-high-speed industrial applications.

[0005] Problems with the improved solution: 1. The oil baffle and oil baffle rib are independent stamping / machining parts, requiring separate mold making, processing, and inventory; during the assembly stage, additional processes such as positioning, bolt tightening, and clearance calibration are required, increasing labor, material, and warehousing costs simultaneously and lengthening the mass production cycle; 2. The separate oil baffle components have a solid thickness and installation gap, encroaching on the space for gear and bearing arrangement. The housing can only be enlarged to compensate for the internal space, which conflicts with the current trend of high power density, lightweight, and miniaturization of reducers, and has extremely poor adaptability to the compact space scenarios of aviation and new energy electric drives; 3. When the equipment is running at high speed, the separate oil baffle is subjected to continuous impact from the oil, causing vibration and resonance with the housing, which can easily lead to bolt loosening and baffle deformation; there are also issues at the joint between the baffle and the housing. 4. With fixed gaps, splashed oil can pass through the gaps, significantly reducing the oil-blocking effect and failing to completely block the oil flow; 5. The split oil-blocking structure relies only on solid plates to block local oil, which is a passive oil-blocking method. It cannot cut off the continuous oil film attached to the shell, cannot trap air to form micro-air cavities, and cannot weaken the intensity of oil turbulence; it can only slightly reduce oil splashing, and does not fundamentally improve the core defects such as oil stirring loss, air entrapment, and temperature rise; 6. The oil baffle is mostly made of thin steel plate stamping, with sharp corners and no rounded transition. It is easy to wear and deform under long-term oil flushing; after long-term vibration and loosening of the fastening bolts, the baffle is at risk of falling off. The fallen parts can jam gears and bearings, causing serious equipment failure; the split parts cannot be integrated with the shell base material, and the wear resistance and impact resistance are far lower than the shell body. Summary of the Invention

[0006] To address the aforementioned problems, this invention provides a reducer housing wall and reducer with a biomimetic dung beetle-like surface convex structure. Inspired by the non-smooth surface anti-adhesion and anti-coating mechanism of the dung beetle, the convex array cuts off the continuous attached oil film on the inner wall of the housing, significantly reducing the effective contact area between the lubricating oil and the housing wall, breaking up large, high-speed splashing oil droplets, and accelerating the rapid return of oil to the oil sump through micro-guided grooves. This effectively suppresses oil churning losses, oil air entrapment, housing temperature rise, and exhaust oil leakage problems under high-speed operating conditions. The biomimetic structure is integrally cast with the housing, eliminating the need for additional oil baffles, oil baffle ribs, or other auxiliary parts. The structure is compact, easy to assemble, and highly producible, making it widely applicable to electric drive reducers for new energy vehicles, industrial gear reducers, and high-speed micro-reduction devices for aviation, offering significant energy-saving and efficiency-enhancing advantages.

[0007] This invention proposes a reducer housing wall with a biomimetic dung beetle-like surface convex structure. The reducer housing includes an upper and lower housing that interlock, with a gear transmission pair inside and a lubricating oil reservoir at the bottom. The inner wall of the reducer housing is integrally formed with several ellipsoidal convex humps resembling those of a dung beetle's pronotum, forming a convex hump array structure. This ellipsoidal convex hump array of the dung beetle's pronotum possesses natural fluid characteristics such as viscosity reduction, gas interception, and continuous oil film breaking, forming the core structural basis for achieving low oil churning loss. Existing technologies commonly use artificial micro-pits and circular protrusions, which, while reducing drag to some extent, have a fatal flaw: conventional structures lack the streamlined film-breaking ability of the dung beetle's ellipsoidal humps, making them prone to... It generates boundary layer eddies, oil accumulation, and air entrainment; it cannot form a stable micro-air film, resulting in low drag reduction efficiency; it cannot adapt to high-speed oil droplet impact and breakup, and its effectiveness is significantly reduced under high-speed conditions. Moreover, existing biomimetic technologies only act on the surfaces of moving pairs (gear tooth surfaces and bearing surfaces), failing to solve the problem of overall loss in the housing due to oil churning on the inner wall. The application location and technical scenario are completely different. The convex hull array structure composed of several ellipsoidal missing convex hulls is arranged in an alternating odd and even row pattern. This ellipsoidal missing convex hull array with alternating odd and even rows forms a uniform and stable micro-air cavity grid structure, which can effectively buffer the turbulent impact intensity of high-speed oil hitting the wall surface. It avoids the problems of high-speed oil scouring and violent turbulence carrying a large amount of air on traditional smooth wall surfaces. Traditional reducers are much more efficient. The existing structure of adding an independent oil baffle to the inner wall of the reducer can only achieve oil blocking and flow guidance. This invention forms a stable micro-air cavity by arranging ellipsoidal convex humps in an alternating pattern, changing the continuous solid-liquid contact of the inner wall of the housing to intermittent point contact + air film isolation. This reduces viscous shear loss from the root of fluid mechanics. Traditional mechanical oil blocking is a passive oil blocking method, which has problems such as many parts, complex assembly, space occupation, high-speed resonance, oil leakage at the joint gap, and inability to improve the oil film attached to the wall. It can only block local oil and cannot weaken the viscous shear resistance from the mechanism. The reducer housing has gap grooves between each pair of adjacent ellipsoidal convex humps, which form a micro-air cavity for accommodating air between the ellipsoidal convex humps. This invention is not a single biomimetic ellipsoidal convex hump structure, but a complete set of coordinated structures. The same structure: the high-density convex array structure in the high-speed impact zone of the inner wall of the shell breaks up oil droplets, and the low-density convex array structure in the oil pool area of ​​the inner wall of the shell ensures oil return. The gap groove between adjacent convex cavities can stably trap air to form micro-air cavities, completely breaking the continuous attached lubricating oil film of the traditional smooth inner wall, greatly reducing the solid-liquid contact area between the lubricating oil and the shell wall. The annular convex vent plug on the inner wall of the shell prevents leakage. The multi-structure coupling solves the multiple technical contradictions of "high-speed drag reduction, low-speed lubrication, air entrapment prevention, and oil leakage prevention". It completely abandons the traditional separate structures such as oil baffles, oil baffles, and flow dividers. All biomimetic drag reduction structures are integrally cast with the shell, solving the defects of traditional structures such as many parts, easy resonance, complex assembly, and space occupation.

[0008] The ellipsoidal convex hull includes an integrally formed convex hull base and an ellipsoidal notch. The lower end of the ellipsoidal notch and the connection between the convex hull base and the lower end of the convex hull base are connected by a rounded transition. The outer contour of the convex hull base is polygonal. All polygons of the convex hull bases can be rectangular, rhomboid, quadrilateral, and / or pentagonal. Adjacent convex hull bases can be the same type of polygon or polygons of different shapes mentioned above, and each corner of the polygon is rounded. The lower end face of the convex hull base is integrally cast into the inner wall of the reducer housing. The top of the ellipsoidal notch is rounded. The rounded ellipsoidal convex hull can break the large volume oil droplets splashed at high speed by the gear into discrete small oil droplets, weakening the viscous shear resistance of the oil. The biomimetic structure of this invention can effectively block the continuous oil film circulation agitation. Under the rated operating condition of 12000 rpm, compared with the traditional light... The sliding inner wall structure reduces oil stirring power loss by 22.3% and improves the overall transmission efficiency of the reducer by 1.75%, effectively reducing equipment energy consumption and meeting the needs of new energy energy conservation. Each corner of the polygonal outline of the ellipsoidal notch top and the convex hull base is rounded, and the connection between the lower end of the ellipsoidal notch and the convex hull base is a rounded transition design. The overall structure is rounded without sharp edges or stress concentration points, avoiding the defects of traditional ribbed structures such as easy wear of corners and easy generation of eddy current impact. The convex hull and the shell base material are integrally fused and molded, with high structural strength and good integrity. It is not easy to wear, deform or fall off when subjected to high-speed oil flushing and media impact for a long time. The operation stability and durability are significantly better than the traditional split oil baffle structure, greatly improving the overall service reliability of the reducer.

[0009] The gap groove between each pair of adjacent ellipsoidal convex humps is a V-shaped flow guide groove. The angle between the two inclined surfaces at the bottom of the groove and the horizontal plane is 14°-16°, the groove width is 0.9mm-1.1mm, and the groove depth is 0.15mm-0.22mm. The V-shaped flow guide groove runs through the micro-air chamber between all the convex hump bases. The setting of the V-shaped flow guide groove can accelerate the oil to flow back to the oil pool quickly along the micro-air chamber, effectively suppressing the problems of oil churning loss, oil air entrapment, shell temperature rise, and exhaust oil leakage under high speed conditions. The setting of the V-shaped flow guide groove also avoids the sharp edges of the outer edge of the convex hump base, avoiding the defects of easy wear of the corners of the rib groove structure and easy generation of eddy current impact. The existing smooth flow guide surface can only change the oil flow direction and cannot cut off the continuous oil film attached to the wall. At high speed, there is still a large area of ​​oil film adhering to the wall and high shear loss. There is no drag reduction mechanism, and the energy saving effect is negligible.

[0010] The convex hull array structure can be integrally set on the arc-shaped high-speed splash impact area on both sides of the gear on the inner wall of the reducer housing, the oil immersion area at the bottom of the inner wall of the reducer housing, the inner side of the exhaust plug on the inner wall of the reducer housing, and / or the top of the inner wall of the reducer housing. The fully differentiated bionic convex hull array structure is formed in one step by pre-setting the inverted curved surface of the mold, without secondary machining process. At the same time, it avoids the problems of high-speed resonance, oil blockage failure of the docking gap, and occupation of internal space of the existing split oil blocking structure, which greatly improves the utilization rate of the internal space of the housing, adapts to the development trend of miniaturization and lightweight of reducers, and has excellent mass production adaptability.

[0011] The major axis dimension of the bottom surface of each ellipsoidal notch is 2.5mm-4.0mm, the minor axis dimension of the bottom surface of the ellipsoidal notch is 1.2mm-2.0mm, the protrusion height of the ellipsoidal notch is 0.3mm-0.6mm, and the top fillet radius of the ellipsoidal notch is R=0.15mm.

[0012] The center-to-center distance between any two ellipsoids in the same row is 4.1mm-5.2mm-6.0mm, and the distance between any two adjacent rows is 1.9mm-2.4mm-3.0mm. Depending on the functional needs of each area, the inner wall of the reducer housing can be divided into different zones for differentiated arrangement. The arrangement density of the convex array structure in the arc-shaped high-speed splash impact zone on both sides of the gear is increased by 20% compared to the normal arrangement density across the entire area, in order to enhance the high-speed oil film breaking and turbulence reduction effect. The arrangement density of the convex array structure in the oil pool wetting zone at the bottom of the housing is reduced by 30% compared to the normal arrangement density across the entire area, in order to retain a smooth oil return channel and ensure that the lubricating oil returns quickly and fully lubricates the bearing and gear meshing pair under low-speed idling conditions. A ring-shaped high-density convex array structure is set on the inner side of the exhaust plug, which can form a ring-shaped oil barrier to effectively prevent high-speed splashed oil from entering the exhaust plug pores, and completely solve the oil seepage and leakage faults caused by high pressure inside the high-speed housing. The convex array structure adopts a completely staggered arrangement of odd and even rows.

[0013] A speed reducer includes a speed reducer housing wall with a biomimetic dung beetle surface convex hull structure, which can be applied to high-speed electric drive speed reducers for new energy vehicles, industrial horizontal gear reducers, or aerospace micro high-speed speed reducers; the biomimetic convex hull array structure is adapted to speed reducer scenarios with different speeds and materials, and the parameters cover the entire speed range of low, medium and high speeds.

[0014] A speed reducer includes a high-speed electric drive speed reducer for new energy vehicles. This is a two-speed electric drive speed reducer for new energy passenger vehicles. The speed reducer housing is integrally formed by high-pressure die casting of aluminum alloy, adaptable to a maximum input speed of 15,000 rpm, which is currently the mainstream high-speed reduction condition for new energy vehicles. The inner wall of the speed reducer housing is fully arranged with a convex hull array structure composed of several ellipsoidal notches and convex hulls resembling the pronotum of a dung beetle. The standard parameters of the convex hull array structure are: the major axis dimension of the ellipsoidal notch is 3.2 mm, the minor axis dimension is 1.6 mm, the convex height is 0.4 mm, and the top corner radius R = 0.15 mm; the center distance between any two ellipsoidal notches in the same row is 5.2 mm, and the distance between adjacent rows is 2.4 mm, using a completely staggered odd-even row arrangement. Meanwhile, the reducer housing adopts a zoned differentiated arrangement: the arrangement density of the convex array structure in the arc-shaped high-speed splash impact zone on both sides of the gear is 20% higher than the standard parameter arrangement density of the full-area convex array structure, enhancing the high-speed oil film cut-off and turbulence reduction effect; the arrangement density of the convex array structure in the oil sump wetting zone at the bottom of the reducer housing is 30% lower than the standard parameter arrangement density of the full-area convex array structure, retaining a smooth oil return channel to ensure rapid return of lubricating oil and sufficient lubrication of bearings and gear meshing pairs under low-speed idling conditions; the inner wall of the housing between two adjacent ellipsoidal convex bulges is integrally formed with a V-shaped flow guide groove, and the bottom of the groove has two inclined surfaces. The groove has an angle of 15° with the horizontal plane, a width of 1 mm, a depth of 0.2 mm, and a micro-air cavity that runs through all the convex bases. The inner wall of the exhaust plug of the reducer housing is provided with a circumferentially arranged annular high-density convex array structure protective strip with a width of 12 mm. The high-density convex array structure parameters are as follows: the major axis dimension of the bottom surface of each ellipsoidal notch is 2.5 mm, the minor axis dimension of the bottom surface of the ellipsoidal notch is 1.2 mm, the convex height of the ellipsoidal notch is 0.3 mm, and the depth of the V-shaped guide groove is 0.15 mm; the center distance between any two ellipsoidal notches in the same row is 4.1 mm, and the distance between two adjacent rows is 1.9 mm.

[0015] A speed reducer includes an industrial horizontal gear reducer. The reducer housing is made of gray cast iron sand casting. The rated maximum speed of the equipment is 6000 rpm, and it is mainly designed for heavy-duty and long-term continuous operation. In view of the characteristics of industrial speed reducers, such as high lubricating oil viscosity, large oil flow and high oil return requirements, the size of the convex hull array structure is enlarged proportionally, while the layout area is simplified. The specific parameters of the convex hull array structure are as follows: the major axis dimension of the bottom surface of each ellipsoidal notch is 4.0 mm, the minor axis dimension of the bottom surface of the ellipsoidal notch is 2.0 mm, the convex height of the ellipsoidal notch is 0.6 mm, and the depth of the V-shaped guide groove is 0.22 mm; the center distance between any two ellipsoidal notches in the same row is 6.0 mm, and the distance between two adjacent rows is 3.0 mm; the convex hull array structure is only arranged on the top of the inner wall of the reducer housing and in the arc-shaped high-speed splash impact area on both sides of the gear, while the oil sump area at the bottom of the reducer housing retains a completely smooth inner wall, so as to avoid the convex hull array structure from hindering the return flow of large-flow lubricating oil and ensuring sufficient lubrication under heavy load conditions.

[0016] A speed reducer includes an aviation micro high-speed speed reducer with a housing made of precision-cast titanium alloy. The entire unit is lightweight, compact, and designed for ultra-high speed operation, with a rated operating speed of up to 20,000 rpm. To address the characteristics of high-speed airflow, severe oil atomization, and easy air entrapment and oil leakage, the size of the convex hull array structure is proportionally reduced, and a high-density uniform arrangement scheme is adopted throughout the entire area. Specific parameters of the convex hull array structure: the major axis dimension of the bottom surface of each ellipsoidal notch is 2.5mm, the minor axis dimension of the bottom surface of the ellipsoidal notch is 1.2mm, the convex height of the ellipsoidal notch is 0.3mm, the depth of the V-shaped guide groove is 0.15mm, there is no sparse area in the entire area, and the micro-air film is uniformly intercepted throughout the inner wall to suppress ultra-high speed oil atomization and air entrapment; the structure is thin and light, the convex hull array structure is extremely small in size, does not occupy the internal assembly gap of the precision shell, and has no risk of motion interference.

[0017] Beneficial effects 1. Significantly reduces oil churning loss and improves transmission efficiency. This invention is not based on ordinary circular protrusions, square protrusions, or random pits, but rather strictly replicates the streamlined ellipsoidal dune protrusion of the dung beetle's pronotum. It mimics the non-smooth surface anti-adhesion mechanism of the dung beetle, trapping air through the micro-cavities in the gaps of the ellipsoidal protrusion, cutting off the continuous lubricating oil film on the shell wall, reducing the solid-liquid contact area, and breaking up high-speed splashing oil droplets, achieving a coupling effect of "film breaking + stable flow + rapid oil return". Under rated operating conditions, compared with the traditional smooth inner wall structure, the oil churning power loss is reduced by 22.3%, and the overall transmission efficiency of the reducer is increased by 1.75%, effectively reducing equipment energy consumption and adapting to the energy-saving needs of new energy sources.

[0018] 2. Integrated molding simplifies assembly and reduces production costs; the biomimetic convex hull array structure and V-shaped guide groove are integrally cast with the reducer housing, eliminating the need for additional oil baffles, oil baffles and other auxiliary parts, reducing assembly processes and parts inventory costs, eliminating resonance and docking failure problems of split structures, higher utilization of internal space of the housing, and significantly improved structural compactness, adapting to the trend of equipment miniaturization and lightweight development, and can be molded in one piece, with excellent mass production performance.

[0019] 3. Suppresses oil entrapment and foaming, reducing the operating temperature rise of the housing; the biomimetic non-smooth structure weakens the turbulence intensity generated by the high-speed impact of oil on the wall, significantly reducing oil entrapment, with the oil entrapment rate decreasing from 8.6% in the traditional structure to 3.1%; the steady-state operating temperature of the housing is reduced by 6.2℃, effectively slowing down the aging rate of the lubricating oil, ensuring the lubrication stability of gears and bearings, and extending the overall service life of the reducer.

[0020] 4. Eliminates high-speed oil leakage faults and has strong adaptability to all working conditions; by setting a ring-shaped high-density biomimetic convex hull array structure protective belt on the inside of the exhaust plug, it effectively blocks splashed oil from entering the exhaust plug, completely solving the problem of shell oil leakage under high speed conditions; at the same time, it adopts a differentiated density arrangement of shell zones, with denser density in the high-speed impact zone to reduce drag and sparser density in the bottom oil pool zone to ensure oil return, perfectly adapting to the operating conditions of various types of deceleration equipment such as high and low speed, new energy, industrial, and aviation, with extremely strong versatility.

[0021] 5. The structure is wear-resistant and reliable with a long service life; the biomimetic convex hull array structure adopts a rounded transition design, which eliminates stress concentration and is not easily worn or deformed by long-term oil scouring. The one-piece molded shell structure has high strength and no risk of loosening or falling off. The equipment's operational stability and durability are significantly better than the traditional split oil baffle structure. Attached Figure Description

[0022] Figure 1 This is a partially enlarged schematic diagram of the convex hull array structure of the reducer housing of the present invention.

[0023] Figure 2 This is a diagram illustrating the effect of the convex hull array structure partitioning of the present invention on the reducer housing.

[0024] Figure 3 This is a magnified schematic diagram of the convex hull structure area on the surface of the biomimetic dung beetle of this invention.

[0025] Figure 4 This is a schematic diagram of the odd-even row alternating arrangement of the convex hull structure on the surface of the biomimetic dung beetle of the present invention.

[0026] Figure 5 This is a schematic diagram of the distribution structure of the biomimetic dung beetle surface convex structure of the present invention in the housing of an electric drive reducer. Figure 1 .

[0027] Figure 6 This is a schematic diagram of the distribution structure of the biomimetic dung beetle surface convex structure of the present invention in the housing of an electric drive reducer. Figure 2 .

[0028] Figure 7 This is a schematic diagram of the distribution structure of the biomimetic dung beetle surface convex structure of the present invention in the housing of an electric drive reducer. Figure 3 .

[0029] In the picture: 1. Gearbox housing; 2. The ellipsoid lacks a convex hull; 21. Convex hull base; 22. Ellipsoid missing; 3. Gap groove; 4. Arc-shaped high-speed splash impact zones on both sides of the gear; 5. Bottom oil bath immersion area; 6. Inner wall of the exhaust plug. Detailed Implementation

[0030] To make the technical problems solved by the present invention, the technical solutions adopted, and the technical effects achieved clearer, the technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention. Furthermore, it should be noted that, for ease of description, only the parts related to the present invention are shown in the accompanying drawings, not all of them.

[0031] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions.

[0032] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0033] Example 1 See Figures 1-4As shown, a reducer housing wall with a biomimetic dung beetle surface convex structure includes a reducer housing 1, which includes an upper and lower reducer housing that are interlocked. A gear transmission pair is provided inside the housing, and a lubricating oil pool is provided at the bottom of the housing. The inner wall of the reducer housing 1 is partially or entirely integrally formed with several ellipsoidal convex bulges 2 that mimic the pronotum of the Shennong dung beetle, forming a convex bulge array structure. The convex bulge array structure formed by the several ellipsoidal convex bulges 2 is arranged in an alternating pattern of odd and even rows. A gap groove 3 is provided between each pair of adjacent ellipsoidal convex bulges 2 on the inner wall of the reducer housing 1, and the gap groove 3 forms a micro-air cavity between the ellipsoidal convex bulges 2.

[0034] The ellipsoidal convex hull 2 ​​includes an integrally formed convex hull base 21 and an ellipsoidal convex hull 22. The lower end of the ellipsoidal convex hull 22 and the connection with the convex hull base 21 are connected by an arc transition. The outer contour of the convex hull base 21 is a polygon. All polygons of the convex hull base 21 are combinations of rectangles, rhombuses, quadrilaterals and pentagons, and each corner of the polygon is rounded. The lower end face of the convex hull base 21 is integrally cast on the inner wall of the reducer housing. The top of the ellipsoidal convex hull 22 is rounded.

[0035] The gap groove 3 between the two adjacent ellipsoidal convex humps 2 is a V-shaped flow guide groove. The angle between the two inclined surfaces of the groove bottom and the horizontal plane is 14°-16°, the groove width is 0.9mm-1.1mm, and the groove depth is 0.15mm-0.22mm. The V-shaped flow guide groove runs through the air-accommodating micro-cavities between all the convex hump bases 21.

[0036] The convex hull array structure can be integrally set on the arc-shaped high-speed splash impact area on both sides of the gear on the inner wall of the reducer housing 1, the oil pool wetting area at the bottom of the inner wall of the reducer housing 1, the inner side of the exhaust plug on the inner wall of the reducer housing 1, and / or the top of the inner wall of the reducer housing 1.

[0037] The major axis dimension of the bottom surface of each ellipsoidal notch 22 is 2.5mm-4.0mm, the minor axis dimension of the bottom surface of the ellipsoidal notch 22 is 1.2mm-2.0mm, the protrusion height of the ellipsoidal notch 22 is 0.3mm-0.6mm, and the top fillet radius of the ellipsoidal notch 22 is R=0.15mm.

[0038] The center-to-center distance between any two ellipsoids in the same row is 4.1mm-5.2mm-6.0mm, and the distance between any two adjacent rows is 1.9mm-2.4mm-3.0mm. The convex hull array structure adopts a completely staggered arrangement of odd and even rows.

[0039] Example 2 See Figure 1 and Figures 4-7As shown, a reducer includes a high-speed electric drive reducer for new energy vehicles. This reducer is a two-speed electric drive reducer for new energy passenger vehicles. The reducer housing 1 is integrally formed by high-pressure die casting of aluminum alloy, adaptable to a maximum input speed of 15000 rpm, which is currently the mainstream high-speed reduction condition for new energy vehicles. The inner wall of the reducer housing 1 is fully arranged with a convex hull array structure composed of several ellipsoidal convex hulls 2, mimicking the pronotum of the Shennong dung beetle. The standard parameters of the convex hull array structure are: the major axis dimension of the bottom surface of the ellipsoidal convex hull 2 ​​is 3.2 mm, the minor axis dimension of the bottom surface of the ellipsoidal convex hull 2 ​​is 1.6 mm, the convex height of the ellipsoidal convex hull 2 ​​is 0.4 mm, and the top corner radius R of the ellipsoidal convex hull 2 ​​is 0.15 mm; the center distance between any two ellipsoidal convex hulls in the same row is 5.2 mm, and the distance between two adjacent rows is 2.4 mm, adopting a completely staggered arrangement of odd and even rows. See Figures 5-7 As shown, the reducer housing 1 adopts a zoned differentiated arrangement: the arrangement density of the arc-shaped high-speed splash impact zone 4 on both sides of the gear is 20% higher than the standard parameter arrangement density of the full-area convex hull array structure; the arrangement density of the convex hull array structure in the oil immersion zone 5 at the bottom of the reducer housing 1 is 30% lower than the standard parameter arrangement density of the full-area convex hull array structure; the inner wall of the housing between two adjacent ellipsoidal convex hulls 2 is integrally formed with a V-shaped guide groove, the angle between the two inclined surfaces at the bottom of the groove and the horizontal plane is 15°, the groove width is 1mm, the groove depth is 0.2mm, and the groove extends through... The air-accommodating micro-cavities are located between all the convex bases 21; the inner wall 6 of the exhaust plug of the reducer housing 1 is circumferentially provided with a 12mm wide annular high-density convex array structure protective strip. The high-density convex array structure parameters are as follows: the major axis dimension of the bottom surface of each ellipsoidal notch 22 is 2.5mm, the minor axis dimension of the bottom surface of the ellipsoidal notch 22 is 1.2mm, the convex height of the ellipsoidal notch 22 is 0.3mm, and the depth of the V-shaped guide groove is 0.15mm; the center distance between any two ellipsoidal notches 22 in the same row is 4.1mm, and the distance between two adjacent rows is 1.9mm.

[0040] Bench test conditions: oil temperature 45℃, rated lubricating oil level, and steady-state operation at 12000rpm; test results: oil churning loss decreased from 1.12kW to 0.87kW, a reduction of 22.3%; transmission efficiency increased by 1.75%; steady-state oil temperature decreased by 6.2℃, air entrapment rate was significantly reduced, and there were no oil leaks from the exhaust plug, oil stagnation, or abnormal eddy current disturbances, fully meeting the long-term durability requirements of new energy high-speed electric drives.

[0041] Example 3 See Figure 1 and Figure 4As shown, a reducer includes an industrial horizontal gear reducer. The reducer housing 1 is made of gray cast iron sand casting. The rated maximum speed of the equipment is 6000 rpm, mainly designed for heavy-duty and long-term continuous operation. In view of the characteristics of industrial reducers such as high lubricating oil viscosity, large oil flow and high oil return requirements, the size of the convex hull array structure is enlarged proportionally, while the layout area is simplified. The specific parameters of the convex hull array structure are as follows: the major axis dimension of the bottom surface of each ellipsoidal notch 22 is 4.0 mm, the minor axis dimension of the bottom surface of the ellipsoidal notch 22 is 2.0 mm, the convex height of the ellipsoidal notch 22 is 0.6 mm, and the depth of the V-shaped guide groove is 0.22 mm; the center distance between any two ellipsoidal notches 22 in the same row is 6.0 mm, and the distance between two adjacent rows is 3.0 mm; the convex hull array structure is arranged only on the top of the inner wall of the reducer housing 1 and in the arc-shaped high-speed splash impact area on both sides of the gear, while the bottom oil pool area of ​​the reducer housing 1 retains a completely smooth inner wall.

[0042] Actual test results: During continuous full-load operation at 6000rpm, the oil churning loss was reduced by 16.8%, the overall temperature rise of the housing was stable, and there was no local high temperature accumulation. Compared with traditional smooth-walled housings, the service life of lubricating oil was improved, and the phenomenon of oil accumulation and wall adhesion inside the housing was basically eliminated, making it suitable for 24-hour continuous operation of industrial equipment.

[0043] Example 4 See Figure 1 and Figure 4 As shown, a speed reducer includes an aviation micro high-speed speed reducer. The housing is made of titanium alloy precision casting, which makes the whole machine lightweight, small space, and capable of ultra-high speed operation. The rated working speed can reach 20,000 rpm. In view of the characteristics of ultra-high speed airflow, severe oil atomization, and easy air entrainment and oil leakage, the size of the convex hull array structure is proportionally reduced and a high-density uniform arrangement scheme is adopted throughout the domain. Specific parameters of the convex hull array structure: the major axis dimension of the bottom surface of each ellipsoid 22 is 2.5mm, the minor axis dimension of the bottom surface of the ellipsoid 22 is 1.2mm, the convex height of the ellipsoid 22 is 0.3mm, the depth of the V-shaped guide groove is 0.15mm, there is no sparse area in the entire area, and the micro air film is uniformly intercepted on the entire inner wall to suppress ultra-high speed oil atomization and air entrapment; the structure is thin and light, the convex hull array structure is extremely small in size, does not occupy the internal assembly gap of the precision shell, and has no risk of motion interference.

[0044] Test results: Under ultra-high speed conditions of 20,000 rpm, the oil churning loss was reduced by 19.5%, effectively suppressing high-speed oil mist turbulence and bubble formation. The housing pressure was stable, with no leakage or abnormal temperature rise, meeting the high reliability, high speed and long service life requirements of aerospace precision reducers.

[0045] Although the invention has been specifically shown and described in conjunction with preferred embodiments, those skilled in the art should understand that various changes in form and detail may be made to the invention without departing from the spirit and scope of the invention as defined in the appended claims, all of which shall be within the scope of protection of the invention.

Claims

1. A reducer housing wall with a biomimetic dung beetle-like surface convex structure, characterized in that: The reducer housing (1) is partially or entirely formed on the inner wall of the reducer housing (1) by a number of ellipsoidal protrusions (2) of a biomimetic dung beetle pronotum forming a convex hull array structure. The convex hull array structure formed by the number of ellipsoidal protrusions (2) is arranged in an alternating pattern of odd and even rows. A gap groove (3) is provided between two adjacent ellipsoidal protrusions (2) on the inner wall of the reducer housing (1). The gap groove (3) forms a micro-air cavity between the ellipsoidal protrusions (2).

2. The reducer housing wall with a biomimetic dung beetle surface convex structure according to claim 1, characterized in that: The ellipsoidal convex hull (2) includes an integrally formed convex hull base (21) and an ellipsoidal convex hull (22). The lower end of the ellipsoidal convex hull (22) and the convex hull base (21) are connected by a rounded transition. The outer contour of the convex hull base (21) is a polygon. All polygons of the convex hull base (21) can be rectangles, rhombuses, quadrilaterals and / or pentagons, and each corner of the polygon is rounded. The lower end face of the convex hull base (21) is integrally cast on the inner wall of the reducer housing. The top of the ellipsoidal convex hull (22) is rounded.

3. The reducer housing wall with a biomimetic dung beetle surface convex structure according to claim 2, characterized in that: The gap groove (3) between the two adjacent ellipsoidal convex hulls (2) is a V-shaped flow guide groove. The angle between the two inclined surfaces of the groove bottom and the horizontal plane is 14°-16°, the groove width is 0.9mm-1.1mm, and the groove depth is 0.15mm-0.22mm. The V-shaped flow guide groove runs through the air micro-cavities between all the convex hull bases (21).

4. The reducer housing wall with a biomimetic dung beetle surface convex structure according to claim 3, characterized in that: The convex hull array structure can be integrally set on the arc-shaped high-speed splash impact area on both sides of the gear on the inner wall of the reducer housing (1), the oil pool wetting area at the bottom of the inner wall of the reducer housing (1), the inner side of the exhaust plug on the inner wall of the reducer housing (1), and / or the top of the inner wall of the reducer housing (1).

5. The reducer housing wall with a biomimetic dung beetle surface convex structure according to claim 4, characterized in that: The major axis of the bottom surface of each ellipsoidal notch (22) is 2.5mm-4.0mm, the minor axis of the bottom surface of the ellipsoidal notch (22) is 1.2mm-2.0mm, the protrusion height of the ellipsoidal notch (22) is 0.3mm-0.6mm, and the top fillet radius of the ellipsoidal notch (22) is R=0.15mm.

6. The reducer housing wall with a biomimetic dung beetle surface convex structure according to claim 5, characterized in that: The center-to-center distance between the two pairs of ellipsoids (22) in the same row is 4.1mm-5.2mm-6.0mm, and the distance between two adjacent rows is 1.9mm-2.4mm-3.0mm. The convex hull array structure adopts a completely staggered arrangement of odd and even rows.

7. A speed reducer, characterized in that: The reducer housing wall, including the biomimetic dung beetle surface convex structure as described in any one of claims 1-6, can be applied to high-speed electric drive reducers for new energy vehicles, industrial horizontal gear reducers, or aerospace micro high-speed reducers.

8. A speed reducer according to claim 7, characterized in that: Including a high-speed electric drive reducer for new energy vehicles, the reducer housing (1) is made of aluminum alloy high pressure die casting in one piece, and is adapted to a maximum input speed of 15000rpm; the inner wall of the reducer housing (1) is arranged with a convex hull array structure composed of several ellipsoidal convex hulls (2) of the pronotum of a dung beetle. The standard parameters of the convex hull array structure are: the major axis dimension of the bottom surface of the ellipsoidal convex hull (22) is 3.2mm, the minor axis dimension of the bottom surface of the ellipsoidal convex hull (22) is 1.6mm, the convex height of the ellipsoidal convex hull (22) is 0.4mm, and the top corner radius of the ellipsoidal convex hull (22) is R=0.15mm; the center distance between any two ellipsoidal convex hulls (22) in the same row is 5.2mm, the distance between two adjacent rows is 2.4mm, and the odd and even rows are arranged in a completely staggered pattern; Meanwhile, the reducer housing (1) adopts a zoned differentiated arrangement: the arrangement density of the convex hull array structure in the arc-shaped high-speed splash impact zone on both sides of the gear is 20% higher than the standard parameter arrangement density of the full-domain convex hull array structure; the arrangement density of the convex hull array structure in the bottom oil pool wetting zone of the reducer housing (1) is 30% lower than the standard parameter arrangement density of the full-domain convex hull array structure; the inner wall of the housing between the two adjacent ellipsoidal convex hulls (2) is integrally formed with a V-shaped guide groove, the angle between the two inclined surfaces of the groove bottom and the horizontal plane is 15°, the groove width is 1mm, the groove depth is 0.2mm, and it penetrates all the convex hulls. The base (21) contains a micro-air cavity; the inner wall of the exhaust plug of the reducer housing (1) is provided with a circumferentially arranged annular high-density convex hull array structure with a width of 12mm. The high-density convex hull array structure parameters are as follows: the major axis dimension of the bottom surface of each ellipsoidal notch (22) is 2.5mm, the minor axis dimension of the bottom surface of the ellipsoidal notch (22) is 1.2mm, the convex height of the ellipsoidal notch (22) is 0.3mm, and the depth of the V-shaped guide groove is 0.15mm; the center distance between two ellipsoidal notches (22) in the same row is 4.1mm, and the distance between two adjacent rows is 1.9mm.

9. A speed reducer according to claim 7, characterized in that: Including industrial horizontal gear reducers, the reducer housing (1) is made of gray cast iron sand casting, and the rated maximum speed of the equipment is 6000 rpm; in view of the characteristics of high viscosity of lubricating oil, large oil flow and high oil return requirements of industrial reducers, the size of the convex hull array structure is enlarged proportionally, and the layout area is simplified. The specific parameters of the convex hull array structure are as follows: the major axis dimension of the bottom surface of each ellipsoidal notch (22) is 4.0 mm, the minor axis dimension of the bottom surface of the ellipsoidal notch (22) is 2.0 mm, the convex height of the ellipsoidal notch (22) is 0.6 mm, and the depth of the V-shaped guide groove is 0.22 mm; the center distance between two ellipsoidal notches (22) in the same row is 6.0 mm, and the distance between two adjacent rows is 3.0 mm; the convex hull array structure is arranged only on the top of the inner wall of the reducer housing (1) and the arc-shaped high-speed splash impact area on both sides of the gear, and the bottom oil pool area of ​​the reducer housing (1) retains a completely smooth inner wall.

10. A speed reducer according to claim 7, characterized in that: Including aerospace micro high-speed reducers, the housing is made of precision cast titanium alloy, and the rated working speed can reach 20,000 rpm; in view of the characteristics of ultra-high speed airflow, severe oil atomization, and easy air entrainment and oil leakage, the size of the convex hull array structure is proportionally reduced and a high-density uniform arrangement scheme is adopted throughout the domain. Specific parameters of the convex hull array structure: the major axis dimension of the bottom surface of each ellipsoidal notch (22) is 2.5mm, the minor axis dimension of the bottom surface of the ellipsoidal notch (22) is 1.2mm, the convex height of the ellipsoidal notch (22) is 0.3mm, the depth of the V-shaped flow guide groove is 0.15mm, and there is no sparse region in the whole domain.

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