Composite material light-weight split axle housing

Abstract

The present application relates to the technical field of automobile parts, and particularly relates to a composite lightweight split type axle housing, which comprises a cast steel axle housing body, an aluminum split type rear cover, a temperature acquisition unit, an adjustable heat dissipation and flow guide assembly and a control unit. The cast steel axle housing body is provided with a main reducer installation cavity, and a connecting flange plate is arranged at a rear end maintenance opening; the aluminum split type rear cover is detachably connected with the connecting flange plate through bolts, and the outer surface is provided with longitudinal heat dissipation ribs. A sealing groove is formed in the end face of the connecting flange plate and a sealing gasket is embedded, and a sealing boss is correspondingly arranged on the inner side of the rear cover, and the sealing gasket is compressed to form a sealing structure. The temperature acquisition unit acquires oil temperature data inside the axle housing, and the control unit determines the vertical impact, parallel flow guide or folding angle position of the flow guide vane according to the oil temperature data and the oil temperature change rate, and performs adaptive heat dissipation control. The present application realizes lightweight combination of cast steel and aluminum alloy, and improves the heat dissipation efficiency in cooperation with the heat dissipation ribs and the active flow guide structure.

Description

Technical Field

[0001] This invention relates to the field of automotive component technology, and in particular to a lightweight, split-type axle housing made of composite materials. Background Technology

[0002] Traditional axle housings are mostly integral cast structures, with the body and rear cover molded as a single piece. This results in a relatively large overall weight, which is detrimental to vehicle weight reduction. The rear cover is made of the same cast steel as the body and is only fastened to the connecting flange at the access opening by bolts. The heat generated by the internal lubricating oil and transmission components during operation relies solely on the natural heat dissipation of the housing wall, which is insufficient to meet the heat dissipation requirements under high-load conditions. At the same time, when internal components malfunction, the entire axle housing must be removed from the frame for repair, making disassembly and maintenance extremely inconvenient. Some existing technologies have introduced split axle housing solutions, in which the rear cover and body are detachably connected by bolts. However, this solution still has significant drawbacks: the rear cover is mostly made of cast iron, which has limited weight reduction effect; the seal between the rear cover and the body relies solely on a single-layer gasket, which is prone to permanent deformation after repeated disassembly and reassembly, reducing the reliability of the seal; and there is no positioning structure between the connecting flange and the rear cover assembly flange, making it difficult to ensure coaxiality after disassembly and reassembly, affecting the durability of the seal.

[0003] Chinese Patent Publication No. CN107336565B discloses a split-type axle housing automotive drive axle, comprising: a drive axle housing, an output half-shaft, a left bearing, and a right bearing. The output half-shaft is movably mounted on the drive axle housing. The left and right bearings are both sleeved on the output half-shaft and located within the drive axle housing. A floating sleeve is also sleeved on the output half-shaft, with its two ends abutting against the left and right bearings respectively. The floating sleeve includes a bushing body, a first spring, a second spring, and a spring plate. The first and second springs are both sleeved on the outer periphery of the bushing body, and the spring plate is embedded within the bushing body, with its inner hole fitting onto the front axle section of the output half-shaft. Therefore, the split-type axle housing automotive drive axle has the following problems: the lack of an active heat dissipation and thermal expansion compensation mechanism leads to limitations in weight reduction, insufficient heat dissipation, and decreased sealing reliability. Summary of the Invention

[0004] Therefore, the present invention provides a lightweight split axle housing made of composite materials to overcome the problems of limited lightweighting, insufficient heat dissipation and reduced sealing reliability caused by the lack of active heat dissipation and thermal expansion compensation mechanisms in the prior art.

[0005] To achieve the above objectives, the present invention provides a lightweight split-type bridge housing made of composite materials, comprising: a cast steel bridge housing body, an aluminum split-type rear cover, a temperature acquisition unit, an adjustable heat dissipation and airflow guiding component, and a control unit. The cast steel bridge housing body is provided with a main reducer mounting cavity, and a maintenance opening communicating with the internal cavity is opened at the rear end. A connecting flange is provided on the edge of the maintenance opening. The shape of the aluminum split-type back cover matches the maintenance opening. The aluminum split-type back cover is fixedly connected to the cast steel bridge housing body in a detachable manner, and the outer surface is provided with several heat dissipation fins. A sealing groove is provided on the end face of the connecting flange, and a sealing gasket is embedded in the sealing groove. A sealing boss is provided on the inner side of the aluminum split rear cover corresponding to the position of the sealing groove. The sealing boss presses the sealing gasket to achieve sealing of the inner cavity of the bridge housing. The temperature acquisition unit is installed in the main reducer mounting cavity to collect oil temperature data of the axle housing cavity in real time. The adjustable heat dissipation and airflow guiding assembly is disposed on the outside of the heat dissipation fins, and includes rotatable airflow guiding blades and an actuator for driving the airflow guiding blades to rotate. The control unit is configured to: receive the oil temperature data in real time, calculate the oil temperature change rate within the current time window; determine the target angle position of the guide vane based on the comparison result of the oil temperature data and a preset oil temperature threshold, and based on the comparison result of the oil temperature change rate and a preset change rate threshold, wherein the target angle position includes a vertical impact angle position, a parallel guide angle position, and a retraction angle position; and output a control signal to the actuator to drive the guide vane to rotate to the target angle position.

[0006] As a preferred technical solution for lightweight split bridge housing made of composite materials, the connecting flange is an annular flange that extends radially outward along the edge of the inspection opening, and its end face is a precision-machined plane. Several connecting bolt holes are evenly distributed on the connecting flange.

[0007] As a preferred technical solution for lightweight split bridge housing made of composite materials, the edge of the aluminum split rear cover is provided with an assembly flange corresponding to the connecting flange, and the assembly flange is provided with an assembly through hole corresponding to the connecting screw hole. The aluminum split rear cover and the cast steel bridge housing body are detachably connected by bolts passing through the assembly through hole and the connecting screw hole.

[0008] As a preferred technical solution for lightweight split-type bridge housing made of composite materials, the heat dissipation ribs are strip-shaped ribs arranged longitudinally and spaced along the outer surface of the aluminum split-type back cover. The extension direction of each strip-shaped rib is parallel to the axial direction of the aluminum split-type back cover, and a guide groove is formed between adjacent strip-shaped ribs.

[0009] As a preferred technical solution for lightweight split-type bridge housings made of composite materials, the sealing gasket is an annular elastic gasket with a thickness greater than the depth of the sealing groove.

[0010] As a preferred technical solution for lightweight split-type bridge housing made of composite materials, the sealing boss is an annular protrusion that extends continuously along the inner edge of the aluminum split-type rear cover. The annular protrusion is embedded in the sealing groove and presses the sealing gasket.

[0011] As a preferred technical solution for lightweight split-type bridge housing made of composite materials, the adjustable heat dissipation and airflow guiding assembly also includes a fixed bracket. The fixed bracket is disposed on the outside of the heat dissipation fins of the aluminum split-type rear cover. The airflow guiding blades are rotatably mounted on the fixed bracket. The actuator is mounted on the fixed bracket and is connected to the airflow guiding blades in a transmission manner.

[0012] As a preferred technical solution for lightweight split bridge housing made of composite materials, the temperature acquisition unit is electrically connected to the control unit through a wire harness. The wire harness passes through a wire hole opened on the shell wall of the cast steel bridge housing body, and a sealing plug is provided at the wire hole.

[0013] As a preferred technical solution for lightweight split-type bridge housings made of composite materials, the control unit is configured as follows: When the oil temperature data is greater than the preset oil temperature threshold and the oil temperature change rate is greater than the preset change rate threshold, the target angle position is determined as the vertical impact angle position; When the oil temperature data is greater than the preset oil temperature threshold but the oil temperature change rate is less than or equal to the preset change rate threshold, the target angle position is determined as the parallel guide angle position; When the oil temperature data is less than or equal to the preset oil temperature threshold, the target angle position is determined as the retraction angle position.

[0014] As a preferred technical solution for lightweight split axle housing made of composite materials, the control unit is further configured to acquire the vehicle's driving speed signal and driving direction signal, determine the basic angle offset based on the driving speed signal, and determine the thermal expansion compensation coefficient of the aluminum split rear cover based on the driving direction signal. Wherein, the vertical impact angle position is the sum of the preset vertical impact angle and the base angle offset; the parallel guide angle position is the sum of the preset parallel guide angle and the correction value of the thermal expansion compensation coefficient.

[0015] Compared with existing technologies, the advantages of this invention are as follows: by combining the cast steel axle housing body with a split aluminum rear cover using heterogeneous materials and employing a detachable connection structure, the overall weight of the axle housing is reduced. Simultaneously, the heat dissipation area is increased by utilizing the heat dissipation fins on the outer surface of the aluminum alloy rear cover. Combined with an adjustable heat dissipation guide assembly, the guide vanes are adaptively adjusted to vertical impact, parallel guidance, or retracted angle positions based on oil temperature data and the comparison of oil temperature change rate with a preset threshold, achieving graded heat dissipation control and effectively improving the axle housing's heat dissipation efficiency and lubricating oil lifespan. The basic angle offset is determined by combining vehicle speed signals and the thermal expansion compensation coefficient by the driving direction signals, dynamically correcting the guide vane angle to compensate for the thermal deformation of the aluminum rear cover under different operating conditions, ensuring the accuracy of heat dissipation control and long-term sealing reliability. The structure of the sealing boss and sealing groove pressing the sealing gasket maintains a stable sealing effect even after multiple disassemblies and reassemblies, improving maintenance convenience. This invention significantly reduces the curb weight while ensuring the axle housing's load-bearing strength and improves heat dissipation performance and sealing durability. Attached Figure Description

[0016] Figure 1 This is a perspective view of a lightweight split-type bridge housing made of composite materials according to an embodiment of the present invention; Figure 2 This is a front view of the cast steel bridge shell body according to an embodiment of the present invention; Figure 3 This is a side view of the cast steel bridge shell body according to an embodiment of the present invention; Figure 4 This is a top view of the aluminum split-type back cover according to an embodiment of the present invention; Figure 5 This is a cross-sectional view of the main view of the aluminum split-type back cover according to an embodiment of the present invention; Figure 6 This is a cross-sectional view of the side view of the aluminum split-type back cover according to an embodiment of the present invention; In the diagram: 1, axle housing body; 2, aluminum rear cover; 11, main reducer mounting cavity; 12, connecting flange; 13, connecting screw hole; 21, heat dissipation fin; 22, assembly through hole. Detailed Implementation

[0017] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to 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.

[0018] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0019] It should be noted that in the description of this invention, the terms "upper", "lower", "left", "right", "inner", "outer", etc., which indicate directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and is not intended to indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention.

[0020] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0021] Please see Figures 1-6 As shown, the present invention provides a lightweight split bridge housing made of composite materials, including: a cast steel bridge housing body 1, an aluminum split rear cover 2, a temperature acquisition unit, an adjustable heat dissipation and airflow guiding component, and a control unit. The cast steel bridge housing body 1 is provided with a main reducer mounting cavity 11, and a maintenance opening communicating with the internal cavity is provided at the rear end. A connecting flange 12 is provided on the edge of the maintenance opening. The aluminum split-type rear cover 2 is shaped to match the maintenance opening. The aluminum split-type rear cover 2 is fixedly connected to the cast steel bridge housing body 1 in a detachable manner, and the outer surface is provided with several heat dissipation fins 21. A sealing groove is provided on the end face of the connecting flange 12, and a sealing gasket is embedded in the sealing groove. A sealing boss is provided on the inner side of the aluminum split rear cover 2 corresponding to the sealing groove. The sealing boss presses the sealing gasket to achieve sealing of the inner cavity of the bridge housing. The temperature acquisition unit is installed in the main reducer mounting cavity 11 to collect the oil temperature data of the axle housing cavity in real time. The adjustable heat dissipation and airflow guiding assembly is disposed on the outside of the heat dissipation fin 21, and includes rotatable airflow guiding blades and an actuator for driving the airflow guiding blades to rotate. The control unit is configured to: receive the oil temperature data in real time, calculate the oil temperature change rate within the current time window; determine the target angle position of the guide vane based on the comparison result of the oil temperature data and a preset oil temperature threshold, and based on the comparison result of the oil temperature change rate and a preset change rate threshold, wherein the target angle position includes a vertical impact angle position, a parallel guide angle position, and a retraction angle position; and output a control signal to the actuator to drive the guide vane to rotate to the target angle position.

[0022] The cast steel bridge housing body 1 is integrally cast from high-strength cast steel, while the aluminum split rear cover 2 is die-cast from aluminum alloy.

[0023] The connecting flange 12 adopts an annular flange structure extending radially outward from the edge of the inspection opening. This design aims to provide sufficient connection area to ensure the connection strength between the rear cover and the axle housing body 1, while also facilitating the circumferential arrangement of the sealing structure. The end face of the connecting flange 12 is a precision-machined plane. This is to ensure surface contact accuracy during assembly with the rear cover through high-precision planar machining, avoiding uneven circumferential stress on the sealing gasket due to insufficient end face flatness. Several connecting bolt holes 13 are evenly distributed on the connecting flange 12. The evenly distributed bolt connection ensures uniform stress distribution throughout the connecting flange 12, preventing localized stress concentration. The number of connecting bolt holes 13 is determined based on the axle housing specifications and load-bearing requirements, and is calibrated through finite element analysis combined with bench tests. The connecting flange 12 is integrally cast with the cast steel axle housing body 1, and the end face is milled for precision machining after casting.

[0024] The edge of the aluminum split-type rear cover 2 is set with an assembly flange corresponding to the connecting flange 12. This design aims to increase the contact area between the rear cover and the connecting flange 12, improving connection stability and the uniformity of sealing surface compression. Assembly through holes 22 are provided on the assembly flange, corresponding one-to-one with the connecting screw holes 13. A detachable fixed connection is achieved by passing bolts through the assembly through holes 22 and screwing them into the connecting screw holes 13. The one-to-one hole design ensures assembly positioning accuracy. During assembly, align the assembly flange with the connecting flange 12, ensuring that each assembly through hole 22 corresponds one-to-one with the connecting screw hole 13. Then, pass the bolts through sequentially and tighten them diagonally according to the specified torque sequence. Disassembly is performed in the reverse order to remove the rear cover. The assembly flange and the aluminum split-type rear cover 2 are integrally die-cast, and the assembly through holes 22 are precision machined after forming.

[0025] The heat dissipation ribs 21 are longitudinally spaced strip-shaped ribs along the outer surface of the aluminum split rear cover 2. This design aims to increase the heat dissipation area of ​​the rear cover and improve heat dissipation efficiency. The extension direction of each strip-shaped rib is parallel to the axis of the rear cover, ensuring that the arrangement of the heat dissipation ribs 21 aligns with the relative airflow direction during vehicle movement, reducing airflow resistance and facilitating heat conduction and diffusion along the length of the heat dissipation ribs 21. Guide grooves are formed between adjacent strip-shaped ribs, guiding airflow directionally along the surface of the heat dissipation ribs 21 and enhancing convective heat transfer. The heat dissipation ribs 21 are integrally die-cast with the rear cover, utilizing the high thermal conductivity of aluminum alloy to rapidly conduct heat from inside the axle housing to the surface of the heat dissipation ribs 21, which is then dissipated to the external environment through air convection. The height, thickness, and spacing of the heat dissipation ribs 21 are determined based on heat dissipation requirements and structural strength requirements, and optimized through thermal simulation analysis combined with experimental verification.

[0026] The sealing gasket adopts a ring-shaped elastic gasket structure. Its purpose is to fill the microscopic gap between the connecting flange 12 and the rear cover through elastic deformation, achieving a sealed protection within the axle housing cavity. The thickness of the sealing gasket is set to be greater than the depth of the sealing groove. This is because when the sealing boss presses against the gasket, the gasket undergoes compressive elastic deformation within the sealing groove, forming uniform contact pressure to ensure reliable sealing. The sealing gasket is made of oil-resistant and high-temperature-resistant elastic material, capable of adapting to the internal working environment of the axle housing. The thickness of the sealing gasket is determined based on the depth of the sealing groove and the required compression amount, and is calibrated through sealing performance tests to ensure that the compression amount is within a reasonable range under the specified assembly torque.

[0027] The sealing boss is an annular protrusion extending continuously along the inner edge of the rear cover, forming a continuous circumferential sealing surface in conjunction with the sealing groove and the sealing gasket. During assembly, the sealing boss moves towards the connecting flange 12 along with the rear cover, embedding itself into the sealing groove and pressing the sealing gasket, causing the gasket to elastically deform and fill the gap, thus forming a reliable seal. The sealing boss and the rear cover are integrally die-cast, and the top surface of the sealing boss is precision-machined after molding to ensure flatness and surface roughness, ensuring uniform contact with the sealing gasket. The cross-sectional dimensions of the sealing boss are designed according to the dimensions of the sealing groove to ensure an appropriate gap between it and the sidewall of the sealing groove after assembly, avoiding interference that could affect assembly accuracy.

[0028] The adjustable heat dissipation and airflow guiding assembly is equipped with a fixed bracket, providing stable mounting support for the guide vanes and actuators, ensuring the relative positional accuracy and motion reliability of each component. The fixed bracket is located outside the heat dissipation fins 21 on the rear cover, allowing the guide vanes to adjust the airflow direction around the heat dissipation fins 21 area. The guide vanes are rotatably mounted on the fixed bracket; by rotating, the angle of attack of the vanes is changed, thereby altering the airflow field distribution across the surface of the heat dissipation fins 21, achieving heat dissipation adjustment under different operating conditions. The actuator is mounted on the fixed bracket and connected to the guide vanes via a transmission mechanism. After receiving control signals from the control unit, the actuator outputs a rotation action, driving the guide vanes to rotate around the axis to the target angle position via a transmission mechanism. The fixed bracket is bolted to the rear cover for easy installation and maintenance. The rotation range of the guide vanes is set according to the heat dissipation adjustment requirements, determined through flow field simulation analysis combined with heat dissipation experiments.

[0029] The temperature acquisition unit is electrically connected to the control unit via a wiring harness, transmitting the acquired oil temperature data to the control unit to provide a real-time temperature input signal for heat dissipation control. The wiring harness passes through a through-hole in the wall of the cast steel bridge housing 1, allowing it to travel from the inside to the outside of the housing. This enables the temperature acquisition unit to be positioned within the oil environment inside the housing for accurate oil temperature measurement. A sealing plug is installed at the through-hole to seal the gap between the wiring harness and the through-hole, preventing lubricating oil leakage and the entry of external impurities. The sealing plug is made of an oil-resistant, high-temperature-resistant elastic material. During assembly, the wiring harness passes through the central hole of the sealing plug, and the sealing plug is inserted into the through-hole, achieving a seal through elastic deformation. The position of the through-hole is determined based on the installation location of the temperature acquisition unit and the layout of the control unit.

[0030] The current time can be selected from 30s to 120s. 30s is selected for heavy load and high temperature conditions to improve response speed, and 120s is selected for stable and uniform speed conditions to smooth out temperature fluctuations. The specific duration is determined by calibration under different load conditions on the actual vehicle.

[0031] The control unit determines the target angle position of the guide vanes based on the oil temperature data and the comparison between the oil temperature change rate and the corresponding threshold, thus achieving adaptive heat dissipation control based on oil temperature conditions. When the oil temperature data is greater than the preset oil temperature threshold and the oil temperature change rate is greater than the preset change rate threshold, the target angle position is determined to be the vertical impact angle position. At this time, the oil temperature is high and still rising rapidly. The guide vanes guide the air to vertically impact the surface of the heat dissipation fins 21 to enhance heat dissipation. When the oil temperature data is greater than the preset oil temperature threshold but the oil temperature change rate is less than or equal to the preset change rate threshold, the target angle position is determined to be the parallel guide angle position. At this time, although the oil temperature is higher than the threshold, it has tended to stabilize, and the parallel guide method is used to maintain stable heat dissipation. When the oil temperature data is less than or equal to the preset oil temperature threshold, the target angle position is determined to be the retracted angle position. At this time, the oil temperature is within the normal range, and the guide vanes retract to reduce airflow resistance. The preset oil temperature threshold is selected as the upper limit of the normal operating temperature range of the lubricating oil, and the preset rate of change threshold is selected as the warning value of the rate of oil temperature rise per unit time. The specific values ​​are determined through bench testing combined with actual vehicle testing and calibration. A finite number of test calibrations are used to test the oil temperature change pattern under different operating conditions to determine reasonable threshold parameters. The control unit receives oil temperature data in real time, calculates the rate of change of oil temperature within the current time window, compares and judges, selects the corresponding target angle position, and outputs a control signal to the actuator to drive the guide vanes to rotate.

[0032] The angle of retraction is such that the guide vanes are parallel to and attached to the outer side of the heat dissipation fins 21, blocking most of the windward section and significantly reducing the intensity of convective heat dissipation.

[0033] The control unit acquires the vehicle's speed and direction signals, and adjusts the angle and position of the guide vanes based on the vehicle's driving status to improve the accuracy and environmental adaptability of heat dissipation control. A base angle offset is determined based on the speed signal. Different vehicle speeds result in different relative airflow speeds, significantly affecting the convective heat transfer effect on the surface of the heat dissipation fins 21. Therefore, the guide vane angle needs to be adjusted accordingly based on the speed. The thermal expansion compensation coefficient of the aluminum split rear cover 2 is determined based on the direction signal. The aluminum rear cover undergoes thermal expansion deformation at different temperatures, which may cause slight changes in the angle and position of the heat dissipation fins 21. The guide vane angle is corrected using the thermal expansion compensation coefficient to compensate for the thermal expansion effect. The vertical impact angle position is the sum of the preset vertical impact angle and the base angle offset. The parallel guide angle position is the sum of the preset parallel guide angle and the correction value of the thermal expansion compensation coefficient. Dynamic adjustment of the target angle is achieved by superimposing the correction values. The correspondence between the base angle offset and the driving speed is determined through flow field simulation analysis combined with experimental testing, and a mapping relationship is established using a linear regression method.

[0034] The thermal expansion compensation coefficient is calculated based on the thermal expansion coefficient of the aluminum alloy material and the temperature field distribution of the rear cover, and corrected through experimental verification. The preset vertical impact angle and parallel guide angle are used as reference angle values, set according to heat dissipation requirements and flow field characteristics; specific values ​​are calibrated through fluid simulation and heat dissipation experiments. The control unit acquires driving speed and direction signals in real time, queries or calculates the corresponding correction amount, adds it to the reference angle, and then selects the target angle position based on the oil temperature judgment result and outputs the control signal. Driving is divided into windward and leeward conditions. When windward, the rear cover temperature is lower, and the compensation coefficient is 0.9–1.0; when leeward, the rear cover's thermal expansion is greater, and the compensation coefficient is 1.0–1.1.

[0035] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

[0036] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A lightweight, split-type bridge housing made of composite materials, characterized in that, include: Cast steel bridge housing body, aluminum split rear cover, temperature acquisition unit, adjustable heat dissipation and airflow guiding components, and control unit; The cast steel bridge housing body is provided with a main reducer mounting cavity, and a maintenance opening communicating with the internal cavity is opened at the rear end. A connecting flange is provided on the edge of the maintenance opening. The aluminum split-type rear cover is shaped to match the maintenance opening. The aluminum split-type rear cover is fixedly connected to the cast steel bridge housing body in a detachable manner, and the outer surface is provided with several heat dissipation fins. A sealing groove is provided on the end face of the connecting flange, and a sealing gasket is embedded in the sealing groove. A sealing boss is provided on the inner side of the aluminum split rear cover corresponding to the sealing groove. The sealing boss presses the sealing gasket to achieve sealing of the inner cavity of the bridge housing. The temperature acquisition unit is installed in the main reducer mounting cavity to collect oil temperature data of the axle housing cavity in real time. The adjustable heat dissipation and airflow guiding assembly is disposed on the outside of the heat dissipation fins, and includes rotatable airflow guiding blades and an actuator for driving the airflow guiding blades to rotate. The control unit is configured to: receive the oil temperature data in real time, calculate the oil temperature change rate within the current time window; determine the target angle position of the guide vane based on the comparison result of the oil temperature data and a preset oil temperature threshold, and based on the comparison result of the oil temperature change rate and a preset change rate threshold, wherein the target angle position includes a vertical impact angle position, a parallel guide angle position, and a retraction angle position; and output a control signal to the actuator to drive the guide vane to rotate to the target angle position.

2. The lightweight split-type bridge housing made of composite materials according to claim 1, characterized in that, The connecting flange is an annular flange that extends radially outward from the edge of the inspection opening. Its end face is a precision-machined plane, and a number of connecting bolt holes 13 are evenly distributed on the connecting flange.

3. The lightweight split-type bridge housing of composite material according to claim 2, characterized in that, The edge of the aluminum split rear cover is provided with an assembly flange corresponding to the connecting flange, and the assembly flange is provided with an assembly through hole 22 corresponding to the connecting screw hole; The aluminum split rear cover and the cast steel bridge housing body are detachably connected by bolts passing through the assembly through hole and the connecting screw hole.

4. The lightweight split-type bridge housing of composite material according to claim 1, characterized in that, The heat dissipation ribs are strip-shaped ribs arranged longitudinally at intervals along the outer surface of the aluminum split back cover. The extension direction of each strip-shaped rib is parallel to the axial direction of the aluminum split back cover, and a guide groove is formed between adjacent strip-shaped ribs.

5. The lightweight split-type bridge housing of composite material according to claim 1, characterized in that, The sealing gasket is an annular elastic gasket with a thickness greater than the depth of the sealing groove.

6. The lightweight split-type bridge housing of composite material according to claim 5, characterized in that, The sealing boss is an annular protrusion that extends continuously along the inner edge of the aluminum split back cover. The annular protrusion is embedded in the sealing groove and presses the sealing gasket.

7. The lightweight split-type bridge housing made of composite materials according to claim 1, characterized in that, The adjustable heat dissipation and airflow guiding assembly also includes a fixed bracket, which is disposed on the outside of the heat dissipation fins of the aluminum split back cover. The airflow guiding blades are rotatably mounted on the fixed bracket, and the actuator is mounted on the fixed bracket and is connected to the airflow guiding blades in a transmission manner.

8. The lightweight split-type bridge housing of composite material according to claim 1, characterized in that, The temperature acquisition unit is electrically connected to the control unit via a wiring harness. The wiring harness passes through a wire hole opened on the shell wall of the cast steel bridge housing body, and a sealing plug is provided at the wire hole.

9. The lightweight split-type bridge housing of composite material according to claim 1, characterized in that, The control unit is configured to: When the oil temperature data is greater than the preset oil temperature threshold and the oil temperature change rate is greater than the preset change rate threshold, the target angle position is determined as the vertical impact angle position; When the oil temperature data is greater than the preset oil temperature threshold but the oil temperature change rate is less than or equal to the preset change rate threshold, the target angle position is determined as the parallel guide angle position; When the oil temperature data is less than or equal to the preset oil temperature threshold, the target angle position is determined as the retraction angle position.

10. The lightweight split-type bridge housing of composite material according to claim 9, characterized in that, The control unit is also configured to acquire the vehicle's driving speed signal and driving direction signal, determine the basic angle offset based on the driving speed signal, and determine the thermal expansion compensation coefficient of the aluminum split rear cover based on the driving direction signal. Wherein, the vertical impact angle position is the sum of the preset vertical impact angle and the base angle offset; the parallel guide angle position is the sum of the preset parallel guide angle and the correction value of the thermal expansion compensation coefficient.

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