Drive axle with hub reduction mechanism

Abstract

The invention relates to the technical field of vehicle transmission, and discloses a drive axle with a hub reduction mechanism, which comprises a shell, an assembly part mounted in the shell and used for assembling a hub reduction gear, a planetary reduction mechanism mounted on the assembly part and used for realizing the functions of speed reduction and torque increase, and a circulation control part arranged in the shell and used for controlling the speed reduction and torque increase of the hub reduction gear. The circulation control part is used for accelerating heat dissipation of a planetary gear set, the negative pressure heat dissipation part is connected to the circulation control part and used for discharging hot air and separating oil liquid, the oil control part is installed on the negative pressure heat dissipation part and used for recycling the oil liquid and conducting heat exchange and cooling on the oil liquid, the circulation control part and the negative pressure heat dissipation part work cooperatively, and a planetary shaft rotates to drive a reciprocating lead screw to rotate; the piston pumps in a reciprocating mode in the heat dissipation pipe, negative pressure is formed to suck heat generated by the planetary gear set in the axle hub and a small amount of oil and gas, the heat dissipation efficiency is in direct proportion to the rotating speed of the planetary speed reduction mechanism, the higher the rotating speed is, the faster the heat dissipation is, and the operation heat of the planetary gear set can be reduced in real time.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle transmissions, and specifically to a drive axle with a wheel side reduction mechanism. Background Art

[0002] The drive axle is a key component of the vehicle transmission system, and its performance has an important impact on the power transmission, driving performance, and reliability of the vehicle. As an important part of the drive axle, the wheel side reduction mechanism can further reduce the wheel speed, increase the torque, and improve the passability and climbing ability of the vehicle without changing the size and transmission ratio of the main reducer.

[0003] The wheel side reduction mechanism usually uses a planetary gear set to achieve the function of speed reduction and torque increase. Although this structure is compact and efficient, in actual operation, due to the complex relative motion between the sun gear, planetary gears, and ring gear in the planetary gear set during high-speed rotation, the contact stress between the gears is large and the meshing frequency is high, resulting in significant frictional heat generation at the gear meshing position; at the same time, the friction between the planetary gear shaft and the bearing, and the violent agitation of the planetary carrier with the lubricating oil during rotation will also continuously generate heat. If these heats cannot be dissipated in time, the temperature inside the drive axle will rise sharply.

[0004] The existing heat dissipation design of the wheel side reduction mechanism relies on the natural heat dissipation of the axle housing. The heat dissipation area is limited and the heat dissipation efficiency is low, making it difficult to meet the heat dissipation requirements of components such as the planetary gear set; there are also some designs that use structures such as heat dissipation fins, but due to the unreasonable layout of the fins and the poor heat conduction path to the heat source inside the axle housing, the heat cannot be effectively transferred to the external environment; in addition, the existing lubricating oil circulation system has an unreasonable flow path planning, and cannot fully contact the heat-generating components for effective heat exchange, resulting in the temperature of the lubricating oil after circulation still being too high to fully cool the inside of the drive axle.

[0005] Continuous high temperature will reduce the viscosity of the lubricating oil, degrade the lubrication performance, exacerbate the wear of components such as gears and bearings, and increase the risk of component failure. Therefore, a drive axle with a wheel side reduction mechanism is proposed to solve the above-mentioned problems. Summary of the Invention

[0006] (I) Technical Problems to be Solved Aiming at the deficiencies of the prior art, the present invention provides a drive axle with a wheel side reduction mechanism, which solves the problems of low heat dissipation efficiency of the wheel side reduction mechanism, continuous high temperature of the lubricating oil circulation system, and reduced service life of components.

[0007] (II) Technical Solutions To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a drive axle with a wheel-side reduction mechanism, comprising a shell, an assembly part installed in the shell for assembling a wheel-side reducer, a planetary reduction mechanism installed on the assembly part for realizing the function of reducing speed and increasing torque, a circulation control part arranged in the shell for accelerating the heat dissipation of the planetary gear set, a negative pressure heat dissipation part connected to the circulation control part for discharging hot air and separating oil, and an oil control part installed on the negative pressure heat dissipation part for recycling the oil and exchanging heat and cooling the oil.

[0008] Preferably, the assembly portion includes an inner shell, the inner shell is rotatably connected to the inner wall of the outer shell, six mounting brackets are installed around the inner wall of the inner shell, a reduction plate is fixedly connected to the inner wall of the shell opening at one end of the inner shell, six heat dissipation holes are opened around the reduction plate, and six oil return holes are also opened around the reduction plate.

[0009] Preferably, the planetary reduction mechanism includes a drive shaft, which is rotatably connected to the inner wall of the reduction plate, and six planetary shafts are rotatably connected to the reduction plate. The end of the drive shaft is fixedly sleeved with gear 1, and three of the planetary shafts are fixedly sleeved with gear 2.

[0010] Preferably, the six planetary shafts are arranged in a circular array with the center of the reduction plate as the axis, the distance between each two planetary shafts is sixty degrees, the distance between each two gears 2 is one hundred and twenty degrees, and the three gears 2 are all meshed with gear 1.

[0011] Preferably, the circulation control part includes a reciprocating screw, the end of the reciprocating screw and the outer wall are fixedly sleeved with limit plates, the reciprocating screw is threadedly connected to a screw slider, the screw slider is located between two limit plates, the screw slider is fixedly connected to a control rod, and the end of the control rod is fixedly connected to a piston.

[0012] Preferably, the negative pressure heat dissipation part includes a heat dissipation pipe, the control rod slides through one end of the heat dissipation pipe, the piston is slidably connected to the inner wall of the heat dissipation pipe, the other end of the heat dissipation pipe is connected and installed with a one-way exhaust valve, and the outer wall of the heat dissipation pipe is connected and installed with an exhaust pipe and a drain pipe.

[0013] Preferably, there are six circulation control parts and six negative pressure heat dissipation parts, the reciprocating screws in the six circulation control parts are respectively installed on the rotating ends of the six planetary shafts, the heat dissipation pipes in the six negative pressure heat dissipation parts are respectively installed on the inner walls of the six mounting frames, and the exhaust pipes in the six negative pressure heat dissipation parts respectively pass through the six heat dissipation holes.

[0014] Preferably, the oil control part includes an oil tank. A cooling hole is formed in the center of the oil tank. The center of the cooling hole is aligned with the center of the speed reduction disc and the center of the drive shaft in sequence. Two pressure relief valves are symmetrically installed on the outer wall of the oil tank. Six return pipes are connected and installed on the oil tank. The six return pipes are all inclined and arranged in a circular array with the center of the oil tank as the axis. Check valves are installed on all six return pipes.

[0015] Preferably, one end of each of the six return pipes away from the oil tank respectively penetrates through six oil return holes. The drain pipes in the six negative pressure heat dissipation parts are fixedly connected to and communicated with the oil tank.

[0016] Preferably, a hub is installed on the speed reduction disc. The planetary reduction mechanism is located inside the hub. A toothed ring is arranged inside the hub. The toothed ring meshes with three gears II. A hub cover is installed at the front end of the hub. A brake disc is installed between the speed reduction disc and the inner shell.

[0017] (III)Advantages Compared with the prior art, the present invention provides a drive axle with a wheel side reduction mechanism, having the following advantages: 1. For the drive axle with the wheel side reduction mechanism, the circulation control part and the negative pressure heat dissipation part work together. The rotation of the planetary shaft drives the reciprocating lead screw to rotate, so that the piston reciprocates and pumps in the heat dissipation pipe, forming a negative pressure to suck the heat and a small amount of oil generated by the planetary gear set in the hub. The gas is quickly discharged through the one-way exhaust valve. The heat dissipation efficiency is proportional to the rotation speed of the planetary reduction mechanism. The higher the rotation speed, the faster the heat dissipation, and the running heat of the planetary gear set can be reduced in real time.

[0018] 2. For the drive axle with the wheel side reduction mechanism, the oil tank of the oil control part collects the oil sent by the drain pipes of the negative pressure heat dissipation part, and heat exchange is carried out through the cooling pipeline connected in the cooling hole. The heat-exchanged oil flows for a long distance through the inclined return pipes for further cooling, and then is sent back to the hub again to compensate for the high-temperature oil, realizing the recycling of the oil and effective temperature reduction.

[0019] 3. For the drive axle with the wheel side reduction mechanism, sufficient heat exchange and heat dissipation effectively reduce the temperature of the lubricating oil, avoid the reduction of the lubricating performance caused by the decrease of the viscosity of the lubricating oil, reduce the wear of components such as gears and bearings, and thus extend the service life of the components.

[0020] 4. For the drive axle with the wheel side reduction mechanism, the structural design of the inner shell, mounting frame, speed reduction disc, etc. of the assembly part facilitates the modular assembly of the planetary gear set and heat dissipation components of the wheel side reducer. This modular design is beneficial to improving the production efficiency, enabling more efficient assembly during the production process, and being more convenient for disassembly and replacement during maintenance, reducing the maintenance difficulty and cost.

[0021] 5. The drive axle with the wheel-side speed reduction mechanism adopts efficient heat dissipation and good lubrication to ensure the stable operation of the drive axle, reduce energy losses caused by excessive wear and high temperature of components, help improve the overall energy utilization efficiency of the vehicle, reduce fuel consumption for fuel vehicles, and increase the cruising range for electric vehicles, showing certain energy-saving potential.

[0022] 6. The drive axle with the wheel-side speed reduction mechanism enables the vehicle to maintain stable operation under different working conditions and environments due to its better heat dissipation and lubrication performance, as well as its strong speed reduction and torque increase capabilities. Whether driving for a long time in a high-temperature environment or operating under complex road conditions, the reliability and performance of the vehicle can be effectively guaranteed, thus broadening the applicable range of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 FIG. is a schematic diagram of the overall structure of a drive axle with a wheel-side speed reduction mechanism proposed by the present invention; Figure 2 FIG. is a schematic diagram of the overall back structure of a drive axle with a wheel-side speed reduction mechanism proposed by the present invention; Figure 3 FIG. is a structural diagram of the inside of the axle hub of a drive axle with a wheel-side speed reduction mechanism proposed by the present invention; Figure 4 FIG. is a connection diagram of the assembly part and the planetary speed reduction mechanism of a drive axle with a wheel-side speed reduction mechanism proposed by the present invention; Figure 5 FIG. is a schematic diagram of the structure of the inner shell of a drive axle with a wheel-side speed reduction mechanism proposed by the present invention; Figure 6 FIG. is a connection diagram of the assembly part and the circulation control part of a drive axle with a wheel-side speed reduction mechanism proposed by the present invention; Figure 7 FIG. is a schematic diagram of the structure of the circulation control part of a drive axle with a wheel-side speed reduction mechanism proposed by the present invention; Figure 8 FIG. is a connection diagram of the negative pressure heat dissipation part and the oil control part of a drive axle with a wheel-side speed reduction mechanism proposed by the present invention.

[0024] In the figure: 1. Outer shell; 2. Assembly part; 21. Inner shell; 22. Mounting bracket; 23. Reduction disk; 24. Heat dissipation holes; 25. Oil return holes; 3. Planetary reduction mechanism; 31. Driving shaft; 32. Planetary shaft; 33. Gear one; 34. Gear two; 4. Circulation control part; 41. Reciprocating lead screw; 42. Limiting piece; 43. Lead screw slider; 44. Control rod; 45. Piston; 5. Negative pressure heat dissipation part; 51. Heat dissipation pipe; 52. One-way exhaust valve; 53. Air extraction pipe; 54. Drain pipe; 6. Oil control part; 61. Oil tank; 62. Cooling holes; 63. Pressure relief valve; 64. Return pipe; 65. Check valve; 7. Axle hub; 8. Hub cover; 9. Brake disc. Specific embodiments

[0025] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0026] Please refer to Figure 1-8 , the present invention provides a technical solution: a drive axle with a wheel side reduction mechanism, including an outer shell 1, an assembly part 2 is installed in the outer shell 1 and is used for assembling the wheel side reducer, a planetary reduction mechanism 3 is installed on the assembly part 2 and is used to achieve the function of reducing speed and increasing torque, a circulation control part 4 is arranged in the outer shell 1 and is used to accelerate the heat dissipation of the planetary gear set, and a negative pressure heat dissipation part 5 is connected to the circulation control part 4 and is used to discharge hot air and separate oil. An oil control part 6 is installed on the negative pressure heat dissipation part 5 and is used to recycle the oil and exchange heat to cool the oil.

[0027] In this embodiment, in order to modularly assemble the planetary gear set and heat dissipation components of the wheel side reducer, the assembly part 2 includes an inner shell 21, the inner shell 21 is rotatably connected to the inner wall of the outer shell 1, six mounting brackets 22 are installed around the inner wall of the inner shell 21, the inner wall of one end of the inner shell 21 is fixedly connected with a reduction disk 23, six heat dissipation holes 24 are formed around the reduction disk 23, and six oil return holes 25 are also formed around the reduction disk 23. The planetary reduction mechanism 3 includes a driving shaft 31, the driving shaft 31 is rotatably connected to the inner wall of the reduction disk 23, six planetary shafts 32 are rotatably connected to the reduction disk 23, and a gear one 33 is fixedly sleeved on the end of the driving shaft 31, and a gear two 34 is fixedly sleeved on three of the planetary shafts 32.

[0028] The planetary gear set is used to further reduce the wheel speed, increase the torque, improve the passing performance and climbing ability of the vehicle without changing the size and transmission ratio of the main reducer. Six planetary shafts 32 are arranged in a circular array with the center of the deceleration disc 23 as the axis. The distance between every two planetary shafts 32 is 60 degrees, and the distance between every two second-stage gears 34 is 120 degrees. All three second-stage gears 34 are meshed with the first-stage gear 33. A bridge hub 7 is installed on the deceleration disc 23. The planetary reduction mechanism 3 is located inside the bridge hub 7. A toothed ring is arranged inside the bridge hub 7, and the toothed ring is meshed with the three second-stage gears 34. A hub cap 8 is installed at the front end of the bridge hub 7. A brake disc 9 is installed between the deceleration disc 23 and the inner shell 21.

[0029] It should be noted that in order to synchronously follow the operating state of the planetary gear set to control the heat dissipation efficiency in real time, the circulation control unit 4 includes a reciprocating lead screw 41. Limit pieces 42 are fixedly sleeved on the end and the outer wall of the reciprocating lead screw 41. A lead screw slider 43 is threadedly connected to the reciprocating lead screw 41. The lead screw slider 43 is located between the two limit pieces 42. A control rod 44 is fixedly connected to the lead screw slider 43. A piston 45 is fixedly connected to the end of the control rod 44. In order to separate the heat and a little oil in a gas-liquid manner, the negative-pressure heat dissipation unit 5 includes a heat dissipation pipe 51. The control rod 44 slidably penetrates one end of the heat dissipation pipe 51, and the piston 45 is slidably connected to the inner wall of the heat dissipation pipe 51. A one-way exhaust valve 52 is connected and installed at the other end of the heat dissipation pipe 51. An air extraction pipe 53 and a liquid discharge pipe 54 are connected and installed on the outer wall of the heat dissipation pipe 51.

[0030] In order to improve the heat dissipation efficiency and adapt to the planetary gear set for cooperative operation, there are six circulation control units 4 and six negative-pressure heat dissipation units 5 respectively. The reciprocating lead screws 41 in the six circulation control units 4 are respectively installed on the rotating ends of the six planetary shafts 32. The heat dissipation pipes 51 in the six negative-pressure heat dissipation units 5 are respectively installed on the inner walls of the six mounting brackets 22. The air extraction pipes 53 in the six negative-pressure heat dissipation units 5 respectively penetrate through the six heat dissipation holes 24.

[0031] It should be noted that in order to centrally cool the oil sucked in under negative pressure and compensate it to the planetary gear set for circulation, the oil control unit 6 includes an oil tank 61. A cooling hole 62 is opened at the center of the oil tank 61. The center of the cooling hole 62 is aligned with the center of the deceleration disc 23 and the center of the drive shaft 31 in sequence. Two pressure relief valves 63 are symmetrically installed on the outer wall of the oil tank 61. Six return pipes 64 are connected and installed on the oil tank 61. All six return pipes 64 are inclined and arranged in a circular array with the center of the oil tank 61 as the axis. Check valves 65 are installed on all six return pipes 64. The ends of the six return pipes 64 away from the oil tank 61 respectively penetrate through the six oil return holes 25. The liquid discharge pipes 54 in the six negative-pressure heat dissipation units 5 are all fixedly connected to and communicated with the oil tank 61.

[0032] Working principle: In actual use, the whole of this case includes two, which are symmetrically installed on both sides of the front axle or rear axle of the vehicle chassis to realize the entire wheel side reduction axle assembly of the vehicle. The input shaft is connected to the drive shaft 31 by using the existing engine transmission system of the drive axle. The input shaft movably penetrates through the cooling hole 62, and the pipeline of a cooling system such as air cooling or water cooling can be connected in the cooling hole 62, so as to better exchange heat for the oil tank 61. During the operation of the planetary reduction mechanism 3, the reciprocating lead screws 41 on the three planetary shafts 32 connected to the current gear two 34 will rotate synchronously, thereby driving the corresponding lead screw sliders 43 to reciprocate between the limit pieces 42, so as to realize the reciprocating pumping of the piston 45 in the heat dissipation pipe 51. The negative pressure formed in the heat dissipation pipe 51 will suck the heat and a small amount of oil fluid of the planetary gear set operation in the axle hub 7 through the air extraction pipe 53. The thrust in the heat dissipation pipe 51 will quickly discharge the gas from the one-way exhaust valve 52. At the same time, the oil fluid will flow along the drain pipe 54 into the oil tank 61 for collection, and quickly exchange heat through the cooling pipeline. The oil fluid after heat exchange will continue to flow over a long distance along the return pipe 64 for further heat exchange and cooling, and then the cooled oil fluid will be sent back into the hub again.

[0033] The rotation speed of the planetary reduction mechanism 3 is proportional to the pumping speed of the piston 45. The higher the rotation speed, the higher the pumping efficiency, that is, the higher the heat dissipation efficiency. It can reduce the heat generated by the operation of the planetary gear set in real time, and send the oil fluid after heat exchange and cooling back into the high-temperature oil fluid for temperature reduction compensation. Sufficient heat exchange and sufficient heat dissipation can reduce the wear of parts and extend the service life of parts.

[0034] The check valve 65 on the return pipe 64 can further prevent the oil fluid in the axle hub 7 from flowing back into the oil tank 61, ensuring the accuracy and stability of the oil fluid circulation system. The hot oil accumulates in the oil tank 61. The pressure relief valve 63 adopts a common breathing valve. When the pressure fluctuates due to the temperature change caused by the evaporation of the liquid in the tank, the breathing valve will act in time to discharge the gas or inhale the air to maintain the pressure balance in the tank, thus ensuring the use safety of the oil tank 61.

[0035] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

Claims

1. A drive axle with a pulley-side reduction mechanism, characterized in that: include: Housing (1); An assembly portion (2) is installed in the housing (1) and is used to assemble the wheel reducer; A planetary reduction mechanism (3) is mounted on the assembly portion (2) and is used to achieve a reduction in speed and torque increase function; A circulation control unit (4), arranged in the housing (1) and used to accelerate heat dissipation of the planetary gear set; The circulation control part (4) comprises a reciprocating screw (41), the end of the reciprocating screw (41) and the outer wall are fixedly sleeved with a limit plate (42), the reciprocating screw (41) is threadedly connected to a screw slider (43), the screw slider (43) is located between two limit plates (42), the screw slider (43) is fixedly connected to a control rod (44), and the end of the control rod (44) is fixedly connected to a piston (45); A negative pressure heat dissipation part (5) connected to the circulation control part (4) and used for discharging hot air and separating oil; The oil control part (6) is installed on the negative pressure heat dissipation part (5) and is used for circulating the oil and exchanging heat and cooling the oil.

2. A drive axle with a pulley-side reduction mechanism according to claim 1, characterized in that: The assembly portion (2) comprises an inner shell (21), the inner shell (21) being rotatably connected to the inner wall of the outer shell (1), six mounting frames (22) being mounted around the inner wall of the inner shell (21), a reduction disc (23) being fixedly connected to the inner wall of a shell opening at one end of the inner shell (21), six heat dissipation holes (24) being arranged around the reduction disc (23), and six oil return holes (25) being arranged around the reduction disc (23).

3. A drive axle with a pulley-side reduction mechanism according to claim 2, characterized in that: The planetary reduction mechanism (3) comprises a drive shaft (31), the drive shaft (31) being rotatably connected to the inner wall of a reduction plate (23), six planetary shafts (32) being rotatably connected to the reduction plate (23), a gear 1 (33) being fixedly sleeved at the end of the drive shaft (31), and three of the planetary shafts (32) being fixedly sleeved with gear 2 (34).

4. A drive axle with a pulley-side reduction mechanism according to claim 3, characterized in that: The six planetary shafts (32) are arranged in a circular array with the center of the reduction plate (23) as the axis, the distance between each two planetary shafts (32) is sixty degrees, the distance between each two gears 2 (34) is one hundred and twenty degrees, and the three gears 2 (34) are all meshed with gear 1 (33).

5. A drive axle with a pulley-side reduction mechanism according to claim 4, characterized in that: The negative pressure heat dissipation portion (5) comprises a heat dissipation pipe (51), the control rod (44) slidably penetrates one end of the heat dissipation pipe (51), the piston (45) is slidably connected to the inner wall of the heat dissipation pipe (51), the other end of the heat dissipation pipe (51) is connected to a one-way exhaust valve (52), and the outer wall of the heat dissipation pipe (51) is connected to an exhaust pipe (53) and a liquid discharge pipe (54).

6. A drive axle with a pulley-side reduction mechanism according to claim 5, characterized in that: The number of the circulation control parts (4) and the number of the negative pressure heat dissipation parts (5) are six, respectively. The reciprocating screws (41) in the six circulation control parts (4) are respectively mounted on the rotating ends of the six planetary shafts (32). The heat dissipation pipes (51) in the six negative pressure heat dissipation parts (5) are respectively mounted on the inner walls of the six mounting frames (22). The exhaust pipes (53) in the six negative pressure heat dissipation parts (5) respectively pass through the six heat dissipation holes (24).

7. A drive axle with a pulley-side reduction mechanism according to claim 6, characterized in that: The oil control unit (6) comprises an oil tank (61), a cooling hole (62) is provided at the center of the oil tank (61), the center of the cooling hole (62) is aligned with the center of the speed reducer (23) and the center of the drive shaft (31) in sequence, two pressure relief valves (63) are symmetrically mounted on the outer wall of the oil tank (61), six return pipes (64) are connected and mounted on the oil tank (61), the six return pipes (64) are all inclined and arranged in a ring array with the center of the oil tank (61) as the axis, and a check valve (65) is mounted on each of the six return pipes (64).

8. A drive axle with a pulley-side reduction mechanism according to claim 7, characterized in that: The six return pipes (64) have one end away from the oil tank (61) and pass through six corresponding oil return holes (25), and the six drain pipes (54) in the negative pressure heat dissipation parts (5) are all fixedly connected to the oil tank (61) and communicated with each other.

9. A drive axle with a pulley-side reduction mechanism according to claim 8, characterized in that: A bridge hub (7) is mounted on the reduction disc (23), the planetary reduction mechanism (3) is located inside the bridge hub (7), a gear ring is arranged inside the bridge hub (7), the gear ring is meshed with three gears (34), a hub cover (8) is mounted at the front end of the bridge hub (7), and a brake disc (9) is mounted between the reduction disc (23) and the inner shell (21).

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