Centralized lubrication electric drive axle

Abstract

Provided in the present invention is a centralized lubrication electric drive axle, comprising an axle housing, both ends of the axle housing being fixedly provided with driving components. The electric drive axle further comprises a cooling and lubricating system for cooling and circulating lubricating oil. An oil sump is fixedly provided on the axle housing, and an oil suction port is provided at the bottom of the oil sump, the oil suction port being in communication with an inlet of the cooling and lubricating system by means of a pipe, and an outlet of the cooling and lubricating system being in communication with oil inlets of the driving components on the left and right sides separately by means of oil inlet pipes; the oil sump is internally provided with oil return pipes for separately communicating oil outlets of the driving components on both sides with the oil sump; when the axle housing is inclined, oil return ports of the two oil return pipes are always located above the oil level of the oil sump, and the oil suction port is always located below the oil level.

Description

A centralized lubrication electric drive bridge Technical Field

[0001] This invention belongs to the field of wheel-side motor lubrication for vehicles, and specifically relates to a centralized lubrication electric drive axle. Background Technology

[0002] Existing wheel-side motor drive axles have the following problems: ① They use round wire motors, resulting in low power density and outdated technology; ② They have low integration, with poor fusion between the motor, reducer, and axle, leading to heavy weight and limited space; ③ They have complex transmission structures, using two-stage parallel shafts which are inefficient, heavy, and affect space; ④ They use segmented axle housings (reducer housing, motor housing, and axle housing middle section), which is not conducive to lightweighting; ⑤ The seals between the motor and reducer are prone to failure, causing motor malfunctions; ⑥ The oil seals between the motor and reducer need to be replaced regularly, resulting in high maintenance costs; ⑦ The reducer suffers from high lubrication losses due to splashing lubrication, leading to low efficiency; ⑧ Water-cooled motors are large in size and have low power and torque density. Examples include patents "CN102139628B A Wheel-Side Drive Axle", "CN102139629A Wheel-Side Drive Axle", and "CN110654224B Wheel-Side Drive System and its Structure in Vehicles".

[0003] Patent number US20240218971A1 employs an oil-cooled, flat-wire distributed wheel-side electric drive axle. The oil pans of the wheel-side electric drive axle are distributed at the bottom of the motors at both ends, with the oil pump mounted in the center of the axle housing. Its characteristics include: ① Large and heavy motors. ② When the vehicle is on an inclined road, the oil in the oil pan of one motor is easily emptied. The patent uses a specially designed oil pump to ensure that even if the oil on one side is emptied, the pump can continue to pump oil from the other side, resulting in high pump costs. ③ When the road is tilted, oil tends to concentrate in the oil pan of one motor. At this time, the rising oil level will cause the rotor to agitate the cooling oil, affecting motor efficiency. ④ The oil pan is designed on the motor. If the reducer lubricating oil enters the motor's oil pan, internal impurities such as iron filings are easily attracted to the motor. Therefore, the first-stage reducer uses agitated oil lubrication, and the motor does not share lubrication, resulting in low system efficiency. Dirty oil in the motor's oil pan can easily backflow into the motor, causing motor insulation failure. Summary of the Invention

[0004] This invention provides a centralized lubrication electric drive bridge.

[0005] The objective of this invention is achieved in the following manner: a centralized lubrication electric drive bridge includes a bridge housing and drive components fixedly mounted at both ends of the bridge housing; it also includes a cooling and lubrication system for cooling and circulating lubricating oil; an oil pan is fixedly mounted on the bridge housing, and an oil suction port is provided at the bottom of the oil pan. The oil suction port is connected to the inlet of the cooling and lubrication system through a pipe, and the outlet of the cooling and lubrication system is connected to the oil inlets of the drive components on the left and right sides respectively through an oil inlet pipe; an oil return pipe is provided inside the oil pan, connecting the oil outlet of each drive component to the oil pan respectively; when the bridge housing is tilted, the oil return ports of the two oil return pipes are always above the oil surface of the oil pan, and the oil suction port is always below the oil surface.

[0006] The oil pan is located in the middle of the axle housing; the two oil return ports are located above the center of the oil pan; and the oil suction port is located at the center of the bottom of the oil pan.

[0007] A groove is provided on one side surface of the bridge housing, and the side of the bridge housing with the groove faces upward. The groove serves as an oil pan, and a cover plate is fixedly installed on top and sealed.

[0008] The oil pan is divided into three parts from left to right by axle housing baffles located on the left and right sides of the oil return port and oil suction port; each axle housing baffle has a through hole at its bottom.

[0009] Each of the drive components includes an integrated motor and an integrated reducer; the motor and the integrated reducer include a common oil passage; the common oil passage is connected to the oil inlet, and the common oil passage is provided with at least one first branch oil passage leading to the internal oil passage of the motor, and at least one second branch oil passage leading to the internal oil passage of the integrated reducer; the oil outlet of the motor is connected to the return oil pipe; the oil outlet of the integrated reducer is connected to the inside of the oil pan through a second return oil pipe.

[0010] The motor and the integrated reducer include a shared end cover for the electric reducer, and a shared oil passage is provided inside the shared end cover; the end of the integrated reducer away from the motor is connected to the wheel-end planetary reducer, and an oil retainer ring is installed instead of an oil seal at the position where an oil seal is installed on the input shaft of the shared end cover for the electric reducer; an oil retainer ring is installed instead of an oil seal at the position where an oil seal is installed between the wheel-end planetary reducer and the integrated reducer; the electric drive axle transmission part uses the same lubricating oil.

[0011] Both ends of the axle housing are directly connected to the reducer housing. The electric reducer shared end cover is connected to the reducer housing but not to the axle housing. The motor and the electric reducer shared end cover are connected to achieve the integration of the motor and the reducer through the shared end cover. The other end of the reducer housing is connected to the wheel-end planetary reducer. The wheel-end planetary reducer is connected to the brake disc. The brake assembly is connected to the reducer housing. The support arm and thrust rod are connected to the axle housing. The shock absorber and airbag are connected to the support arm.

[0012] The cooling and lubrication system includes a coarse filter, a fine filter, an oil pump, and an oil cooler. The oil suction port is connected to the coarse filter inlet via a pipe, the coarse filter outlet is connected to the oil pump inlet via a pipe, the oil pump outlet is connected to the oil cooler inlet via a pipe, the oil cooler outlet is connected to the fine filter inlet via a pipe, and the fine filter outlet is connected to the oil inlets of the drive components on the left and right sides via two oil inlet pipes.

[0013] The cooling and lubrication system also includes an oil manifold plate located at the rear end of the axle housing. The coarse filter, fine filter, oil pump, and oil cooler are all fixedly mounted on the oil manifold plate. The oil manifold plate has internal channels connecting the coarse filter and the oil pump, the oil pump and the oil cooler, and the oil cooler and the fine filter.

[0014] Beneficial effects: Compared with the prior art, the present invention has the following advantages: First, the oil pan and axle housing are integrated, realizing centralized lubrication of the motors at both ends, reducing the size and weight of the motors; Second, the motor and reducer share lubrication, cooling, bearings, and end caps, improving system efficiency, reducing weight, decreasing axial dimensions, and increasing channel space; Third, the oil pump, oil cooler, coarse filter, and fine filter are integrated on the oil circuit board and mounted at the rear end of the axle housing, reducing the number of external pipelines, saving layout space, and improving maintenance convenience; Fourth, a special oil return design ensures that when the vehicle tilts forward, backward, or left or right, the oil in the oil pan does not backflow into the motor and the oil pump does not run dry; Fifth, the oil seals between the motor and the integrated reducer (which can also be replaced with oil retaining rings) and between the integrated reducer and the wheel-end planetary reducer (which can also be replaced with oil retaining rings) only require oil blocking, so there is no need to replace the oil seals throughout their entire life cycle, greatly reducing maintenance costs; Sixth, the axle housing is directly connected to the reducer housing, while the motor and axle housing are separated, resulting in good weight reduction. Attached Figure Description

[0015] Figure 1 is a schematic diagram of the overall structure of the present invention.

[0016] Figure 2 is a schematic diagram of the inside of the oil pan when it is open.

[0017] Figure 3 is a diagram showing the distribution of oil baffles between the motor and the reducer (some parts unrelated to the invention are omitted).

[0018] Figure 4 is a diagram of the cooling and lubrication system.

[0019] Figure 5 is the overall structure oil circuit diagram.

[0020] Figure 6 is a schematic diagram of the common oil passage for the motor and the integrated reducer (irrelevant parts omitted).

[0021] Figure 7 shows the positions of the lubricating oil, return port, and suction port when the vehicle is tilted.

[0022] The names of the components corresponding to the corresponding reference numerals in the figure are as follows: 1. Cooling and lubrication system; 1a. Oil circuit board; 1b. Coarse filter; 1c. Fine filter; 1d. Oil pump; 1e. Oil cooler; 1f. Return oil pipe; 1g. Inlet oil pipe; 1h. Second return oil pipe; 2. Axle housing; 2a. Axle housing baffle plate; 2b. Cover plate; 2c. Oil suction port; 2d. Oil pan; 3. Motor; 4. Integrated reducer; 4a. Reducer housing; 4b. Input common bearing; 4c. Electric reducer common end cover; 4d. Common oil passage; 4e. First branch oil passage; 4f. Second branch oil passage; 4g. Oil inlet; 5. Wheel end planetary reducer; 6. Support arm; 7. Connecting plate; 8. Brake disc; 9. Brake assembly; 10. Shock absorber; 11. Airbag; 12. Thrust rod; 13. Oil baffle ring; 14. Return oil port. Detailed Implementation

[0023] In this invention, unless otherwise expressly specified and limited, the technical terms used in this application shall have the ordinary meaning understood by those skilled in the art. Terms such as “connected,” “linked,” “fixed,” and “set” shall be interpreted broadly, referring to fixed connections, detachable connections, or integral connections; direct connections or indirect connections via an intermediate medium; mechanical connections or electrical connections. Unless otherwise expressly specified and limited, “above” or “below” a second feature may mean that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, “above,” “on top of,” or “on top of” a second feature may mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. “Below,” “under,” or “beneath” a second feature may mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature. Relational terms such as “first,” “second,” etc., are used only 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. The terms used in the description, such as “center,” “lateral,” “longitudinal,” “length,” “width,” “thickness,” “height,” “front,” “rear,” “left,” “right,” “up,” “down,” “vertical,” “horizontal,” “top,” “bottom,” “inner,” “outer,” “axial,” “radial,” “circumferential,” “clockwise,” and “counterclockwise,” 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 simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation.

[0024] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. As shown in Figures 1-7, a centralized lubrication electric drive bridge includes a bridge housing 2, with drive components fixedly mounted at both ends of the bridge housing 2; it also includes a cooling and lubrication system 1 for cooling and circulating lubricating oil; an oil pan 2d is fixedly mounted on the bridge housing 2, and an oil suction port 2c is provided at the bottom of the oil pan 2d. The oil suction port 2c is connected to the inlet of the cooling and lubrication system 1 through a pipe, and the outlet of the cooling and lubrication system 1 is connected to the oil inlets 4g of the drive components on the left and right sides respectively through an oil inlet pipe 1g; an oil return pipe 1f is provided inside the oil pan 2d, connecting the oil outlet of each drive component to the oil pan 2d respectively; when the bridge housing 2 is tilted, the oil return ports 14 of the two oil return pipes 1f are always above the oil surface of the oil pan 2d, and the oil suction port 2c is always below the oil surface. Here, "mounted on" can be located above, below, or inside the bridge housing 2. The oil pan 2d simply needs to be fixed to the axle housing 2 and move or tilt with it. The cooling and lubrication system 1, the two drive components on both sides, and the oil pan 2d form a circulating oil lubrication structure via pipes. An oil suction port 2c is provided at the bottom of the oil pan 2d, including the bottom surface and the area near it. As long as the oil pan 2d moves and tilts with the axle housing 2, the oil suction port 2c must always be below the oil surface to ensure it can always draw oil. The oil suction port 2c is preferably located in the middle of the oil pan 2d. Other locations are also acceptable, as long as it remains below the oil surface. The drive components are preferably the motor 3 and the reducer. The lubrication structure of this invention can lubricate only the motor 3, only the reducer, or both simultaneously. In this invention, only one oil pan 2d needs to be installed on the axle. When the oil pan 2d tilts left, right, or forward and backward, the oil level changes. As long as the return ports 14 of the two return pipes 1f are above the oil surface, the lubricating oil will not flow back into the drive components, such as the motor 3, through the return pipes 1f. This invention achieves the effect of preventing backflow when tilted by setting the positions of the oil pan 2d, the oil suction port 2c, and the oil return port 14 of the oil return pipe 1f. The structure is simple, the cost is low, and the volume and weight of the overall bridge housing 2 are greatly reduced.

[0025] The oil pan 2d is positioned in the middle of the axle housing 2; the two oil return ports 14 are positioned above the center of the oil pan 2d; the oil suction port 2c is located at the center of the bottom of the oil pan 2d. The center of the oil pan 2d in the front-back and left-right directions and the center of the axle housing 2 in the front-back and left-right directions are basically on the same vertical line, only their heights may differ. Here, "middle position" and "center position" include the very center position and a position slightly off-center; a slight deviation is sufficient as long as the oil return port 14 is above the oil surface. The height of the oil return port 14 is set according to the oil level and actual needs. The lubricating oil after cooling the drive components returns to the oil pan 2d through the oil return pipe 1f. The oil return port 14 of the oil return pipe 1f is installed at the center of the oil pan 2d above the oil surface. In this way, when the vehicle tilts, the oil level is basically tilted around the center of the oil surface, with changes in the front-back and left-right positions, but the central oil level remains basically unchanged. Therefore, the lubricating oil will not flow back into the drive components, such as the motor 3, through the oil return port 14 of the oil return pipe 1f. The oil suction port 2c is also designed at the center of the bottom of the lubricating oil in the oil pan 2d. When the vehicle is tilted, the oil level is basically tilted around the center of the oil surface, and the height of the oil surface changes in the front-back and left-right positions, but the height of the central oil surface remains basically unchanged. Therefore, there will be no air evacuation at the oil suction port 2c.

[0026] A groove is provided on one side surface of the axle housing 2, with the grooved side of the axle housing 2 facing upwards. The groove serves as an oil pan 2d, and a cover plate 2b is fixedly installed on top and sealed. For existing axle housings 2 with grooves already present at their bottom, the axle housing 2 can be mounted upside down on the vehicle, with the grooved side facing upwards, and the groove used as the oil pan 2d. By utilizing the internal sealed cavity or groove of the axle housing 2 as the oil pan 2d of the lubrication system, the oil pan 2d does not need to be designed onto the motor 3, reducing the size and weight of the motor 3 and achieving centralized lubrication. For axle housings 2 without grooves, or with grooves whose shape and size are unsuitable for use as oil pan 2d, the present invention allows for redesigning the axle housing 2 as needed, designing grooves on its upper surface, or redesigning the shape and size of the grooves to facilitate its use as oil pan 2d. The cover plate 2b is disposed on the surface of the axle housing 2, covering the groove serving as the oil pan 2d. The cover plate 2b and the oil pan 2d are fixed together with screws, and the mating surfaces and gaps are sealed with sealant; the sealant uses existing technology and will not be described in detail. A cylindrical or other shaped protrusion is provided inside the oil pan 2d. A channel is provided on the protrusion, and the port of the channel, which is the oil suction port 2c, is located at the center of the bottom of the oil pan 2d. The other end of the channel is located on the outer surface of the bridge housing 2 and can be connected to other components via a pipe. The oil pan 2d can also be located above the bridge housing 2; care must be taken to ensure sufficient installation space to avoid interference, and the oil level should preferably not exceed the oil level of the motor 3.

[0027] The oil sump 2d is divided into three parts from left to right by axle housing baffles 2a located on the left and right sides of the oil return port 14 and the oil suction port 2c. Each axle housing baffle 2a has a through hole at its bottom. The axle housing baffles 2a prevent the oil in the oil sump 2d from sloshing and forming ripples, thus stabilizing the oil level to some extent. The oil return pipe 1f can pass through the axle housing 2 or the cover plate 2b, as well as the axle housing baffles 2a. The oil return pipe 1f is sealed to the axle housing 2 or the cover plate 2b using existing static sealing methods, such as sealant or sealing rings.

[0028] Each of the drive components includes an integrated motor 3 and an integrated reducer 4; the motor 3 and the integrated reducer 4 include a common oil passage 4d; the common oil passage 4d is connected to the oil inlet 4g, and the common oil passage 4d is provided with at least one first branch oil passage 4e leading to the internal oil passage of the motor 3, and at least one second branch oil passage 4f leading to the internal oil passage of the integrated reducer; the oil outlet of the motor 3 is connected to the return oil pipe 1f; the oil outlet of the integrated reducer 4 is connected to the inside of the oil pan 2d through a second return oil pipe 1h. The oil outlet of the integrated reducer 4 can be directly set on the housing of the integrated reducer 4, or it can be set on the motor 3 near the oil pan 2d through the oil passage in the common end cover 4c of the electric reducer, in which case the oil passage in the common end cover 4c of the electric reducer is not connected to the oil passage of the motor 3. The second return oil pipe 1h is located at one end of the oil pan 2d, which can be set above the center of the oil pan 2d like the return oil port 14, or it can be set nearby on one side of the oil pan 2d, below the oil surface. After the lubricating oil flows through the motor 3, one path is branched into the integrated reducer 4 to actively lubricate the gears and bearings of the reducer, improving the efficiency of the integrated reducer 4. The integrated reducer 4 and the motor 3 use the same lubricating oil and each has an independent return oil path; they share an oil inlet but not a return oil. The lubricating oil passing through the integrated reducer 4 contains a lot of impurities, and if they share a return oil path, it may affect the motor 3. The non-shared return oil path prevents impurities from entering the motor. The above structure is only the preferred structure; other structures are also within the protection scope of this invention. The lubrication structure in this invention can also lubricate only the motor 3 or only the integrated reducer 4. When only the motor 3 is lubricated: the motor 3 is provided with an oil inlet 4g and an oil outlet, with an oil passage between the oil inlet 4g and the oil outlet. The cooling circulation system is connected to the oil inlet 4g of the motor 3 through an oil inlet pipe 1g, and the oil outlet is located above the center of the oil pan 2d through an oil return pipe 1f. Simultaneously, the structures of the lubricating motor 3 and the integrated reducer 4 can also be lubricated separately through pipelines. For example, the motor 3 and the integrated reducer 4 can be respectively equipped with their own oil inlet 4g and oil outlet, and respectively connected to the cooling circulation system through their own oil inlet pipe 1g, and respectively connected to the oil pan 2d through their own oil return pipe 1f, etc.

[0029] The motor 3 and the integrated reducer 4 share a common end cover 4c, within which a common oil passage 4d is provided. The end of the integrated reducer 4 furthest from the motor 3 is connected to a wheel-end planetary reducer 5. An oil retainer ring 13 is installed at the location where an oil seal is installed on the input shaft of the common end cover 4c, replacing the oil seal. An oil retainer ring 13 is also installed at the oil seal location between the wheel-end planetary reducer 5 and the integrated reducer 4, replacing the oil seal. The electric drive axle transmission uses the same type of lubricating oil. The motor 3 can be an oil-cooled flat wire motor 3; the integrated reducer 4 can be a first-stage parallel shaft reducer. The integrated structure of the motor 3 and the integrated reducer 4 adopts an existing integrated structure.

[0030] The input shaft of the shared end cover 4c of the electric reducer includes a left shaft and a right shaft. The left shaft is the input shaft of the integrated reducer 4, and the right shaft is the part of the motor shaft closer to the motor 3. The part of the motor shaft away from the motor 3 is inserted into and fixed inside the input shaft of the integrated reducer. The motor shaft and the input shaft of the integrated reducer share a bearing. That is, there is no bearing at the front end of the motor shaft, and the input shared bearing 4b on the integrated reducer 4 is used. After integration, the thickness of the end cover and the bearing at both ends are saved axially, so the channel space can be greatly increased. The lubrication of the wheel-end planetary reducer 5 can be self-lubricating, and it does not share the oil circuit and oil pan 2d with the integrated motor 3 and the integrated reducer 4, but the same lubricating oil can be used. In this case, when the same lubricating oil is used, a small amount of oil leakage is allowed between the motor 3, the integrated reducer 4, and the wheel-end planetary reducer 5 inside the entire electric drive bridge. Therefore, there is no need to use oil seals with high sealing performance and no oil leakage, saving the cost of regular maintenance of oil seals.

[0031] Both ends of the axle housing 2 are directly connected to the reducer housing 4a. The shared end cover 4c of the electric reducer is connected to the reducer housing 4a but not to the axle housing 2. The motor 3 is connected to the shared end cover 4c of the electric reducer, realizing the integration of the motor 3 and the reducer's shared end cover. The other end of the reducer housing 4a is connected to the wheel-end planetary reducer 5. The wheel-end planetary reducer 5 is connected to the brake disc 8. The brake assembly 9 is connected to the reducer housing 4a. The support arm 6 and thrust rod 12 are connected to the axle housing 2. The shock absorber 10 and airbag 11 are connected to the support arm 6. A connecting plate 7 is also provided on the upper end of the motor 3, which is used to connect the opening on the axle housing. The reducer housing 4a is the reducer housing. The above components constitute one structure of the electric drive axle assembly. This invention designs an integrated axle housing 2 that is directly connected to the integrated reducer 4, and the motor 3 can be separated and does not need to be integrated with the axle housing 2. The overall weight reduction level of the axle can be improved, and the reliability and NVH performance of the motor 3 can be enhanced.

[0032] The cooling and lubrication system 1 includes a coarse filter 1b, a fine filter 1c, an oil pump 1d, and an oil cooler 1e. The oil suction port 2c is connected to the inlet of the coarse filter 1b via a pipe. The outlet of the coarse filter 1b is connected to the inlet of the oil pump 1d via a pipe. The outlet of the oil pump 1d is connected to the inlet of the oil cooler 1e via a pipe. The outlet of the oil cooler 1e is connected to the inlet of the fine filter 1c via two inlet pipes 1g, which are respectively connected to the inlets 4g of the drive components on the left and right sides. Specifically, the outlet of the fine filter 1c is connected to the inlets 4g of the motors 3 on the left and right sides via two inlet pipes 1g. After lubrication, the outlet of the motor 3 is connected to the oil pan 2d via the return oil pipe 1f, and the outlet of the integrated reducer 4 enters the oil pan 2d via the second return oil pipe 1h. The specific structure and installation method of the coarse filter 1b, fine filter 1c, oil pump 1d, and oil cooler 1e are existing technologies and will not be described in detail.

[0033] The cooling and lubrication system 1 also includes an oil manifold 1a located at the rear end of the axle housing 2. The coarse filter 1b, fine filter 1c, oil pump 1d, and oil cooler 1e are all fixedly mounted on the oil manifold 1a. The oil manifold 1a has internal channels connecting the coarse filter 1b and oil pump 1d, the oil pump 1d and oil cooler 1e, and the oil cooler 1e and fine filter 1c. The oil return port 14 can also be connected to the coarse filter 1b through the internal channels of the axle housing 2 and the oil manifold 1a. The cooling and lubrication system 1 is integrated at the rear end of the axle housing 2, not exceeding the upper and lower planes of the axle housing 2, thus not affecting the interior space or ground clearance. Connecting the various components through the oil passages inside the oil manifold 1a eliminates the need for numerous external connecting pipes; however, external pipes could also be used for connection.

[0034] The present invention has the following advantages: First, the oil pan 2d and the bridge housing 2 are integrated, realizing centralized lubrication of the motors 3 at both ends, reducing the size and weight of the motors 3; Second, the motors 3 and the reducer share lubrication, cooling, bearings, and end caps, improving system efficiency, reducing weight, decreasing axial dimensions, and increasing channel space; Third, the oil pump 1d, oil cooler 1e, coarse filter 1b, and fine filter 1c are integrated on the oil circuit board 1a and assembled at the rear end of the bridge housing 2, reducing the number of external pipelines, saving layout space, and improving maintenance convenience; Fourth, a special... The oil return design ensures that when the vehicle tilts forward, backward, or left or right, the oil in the oil pan 2d will not backflow into the motor 3 and the oil pump 1d will not run dry; Fifth: The oil seal between the motor 3 and the integrated reducer 4 (which can also be replaced with an oil baffle ring 13) and the oil seal between the integrated reducer 4 and the wheel-end planetary reducer 5 (which can also be replaced with an oil baffle ring 13) are only required to block oil, so the oil seals do not need to be replaced throughout their entire life cycle, which greatly reduces maintenance costs; Sixth: The axle housing 2 is directly connected to the reducer housing 4a, and the motor 3 is separated from the axle housing 2, resulting in good weight reduction.

[0035] In practice: Lubricating oil is drawn from the oil pan 2d through the suction port 2c, filtered by the coarse filter 1b, and then drawn by the oil pump 1d and flows into the oil cooler 1e. After being cooled by the oil cooler 1e, the lubricating oil flows into the fine filter 1c. After being filtered by the fine filter 1c, it is delivered to the flat wire motor 3 and the integrated reducer 4 at both ends through the oil inlet pipe 1g. After lubrication and cooling, the lubricating oil returns to the oil pan 2d through the return oil pipe 1f and the second return oil channel to form a circulation.

[0036] This invention utilizes the latest oil-cooled flat wire motor 3, which boasts higher power density, torque density, and efficiency; it employs the latest motor 3 and reducer integration technology, significantly improving channel width, efficiency, and weight reduction; it utilizes centralized lubrication technology to achieve vector control of lubrication and cooling; and it employs integrated lubrication and axle housing 2 technology, drastically reducing the overall axle volume and weight; the entire axle integrates current advanced oil-cooled flat wire technology, electro-reduction integration technology, and centralized lubrication and cooling technology, resulting in a significant improvement in overall weight reduction, efficiency, NVH, channel width, and other comprehensive performance.

[0037] The technical features of the embodiments described above can be combined in any way, and as long as there is no contradiction in the combination of these technical features, they should all be considered within the scope of this specification. Without departing from the overall concept of this invention, any technical solutions based on this invention, as well as equivalent substitutions or modifications, and various changes and improvements made, should also be considered within the scope of protection of this invention.

Claims

1. A centralized lubrication electric drive bridge, comprising a bridge housing, drive components fixedly disposed at both ends of the bridge housing; and a cooling lubrication system for cooling and circulating lubricating oil; characterized in that: An oil pan is fixedly installed on the axle housing. An oil suction port is provided at the bottom of the oil pan. The oil suction port is connected to the inlet of the cooling and lubrication system through a pipe. The outlet of the cooling and lubrication system is connected to the oil inlets of the drive components on the left and right sides through an oil inlet pipe. An oil return pipe is provided inside the oil pan, which connects the oil outlet of each drive component to the oil pan. When the axle housing is tilted, the oil return ports of the two oil return pipes are always above the oil level in the oil pan, and the oil suction port is always below the oil level.

2. The centralized lubrication electric drive bridge according to claim 1, characterized in that: The oil pan is located in the middle of the axle housing; the two oil return ports are located above the center of the oil pan; and the oil suction port is located at the center of the bottom of the oil pan.

3. A centralized lubrication electric drive bridge according to claim 1, characterized in that: A groove is provided on one side surface of the bridge housing, and the side of the bridge housing with the groove faces upward. The groove serves as an oil pan, and a cover plate is fixedly installed on top and sealed.

4. A centralized lubrication electric drive bridge according to claim 3, characterized in that: The oil pan is divided into three parts from left to right by axle housing baffles located on the left and right sides of the oil return port and oil suction port; each axle housing baffle has a through hole at its bottom.

5. A centralized lubrication electric drive bridge according to claim 1, characterized in that: Each of the drive components includes an integrated motor and an integrated reducer; the motor and the integrated reducer include a common oil passage; the common oil passage is connected to the oil inlet, and the common oil passage is provided with at least one first branch oil passage leading to the internal oil passage of the motor, and at least one second branch oil passage leading to the internal oil passage of the integrated reducer; the oil outlet of the motor is connected to the return oil pipe; the oil outlet of the integrated reducer is connected to the inside of the oil pan through a second return oil pipe.

6. A centralized lubrication electric drive bridge according to claim 5, characterized in that: The motor and the integrated reducer include a shared end cover for the electric reducer, and a shared oil passage is provided inside the shared end cover; the end of the integrated reducer away from the motor is connected to the wheel-end planetary reducer, and an oil retainer ring is installed instead of an oil seal at the position where an oil seal is installed on the input shaft of the shared end cover for the electric reducer; an oil retainer ring is installed instead of an oil seal at the position where an oil seal is installed between the wheel-end planetary reducer and the integrated reducer; the electric drive axle transmission part uses the same type of lubricating oil.

7. A centralized lubrication electric drive bridge according to claim 6, characterized in that: The input shaft of the electric reducer shared end cover includes a left shaft and a right shaft. The left shaft is the input shaft of the integrated reducer, and the right shaft is the part of the motor shaft closer to the motor. The part of the motor shaft away from the motor is inserted into the interior of the integrated reducer input shaft and fixed. The motor shaft and the integrated reducer input shaft share a common bearing.

8. A centralized lubrication electric drive bridge according to claim 6, characterized in that: Both ends of the axle housing are directly connected to the reducer housing. The electric reducer shared end cover is connected to the reducer housing but not to the axle housing. The motor and the electric reducer shared end cover are connected to achieve the integration of the motor and the reducer through the shared end cover. The other end of the reducer housing is connected to the wheel-end planetary reducer. The wheel-end planetary reducer is connected to the brake disc. The brake assembly is connected to the reducer housing. The support arm and thrust rod are connected to the axle housing. The shock absorber and airbag are connected to the support arm.

9. A centrally lubricated electric drive bridge according to any one of claims 1-8, characterized in that: The cooling and lubrication system includes a coarse filter, a fine filter, an oil pump, and an oil cooler. The oil suction port is connected to the coarse filter inlet via a pipe, the coarse filter outlet is connected to the oil pump inlet via a pipe, the oil pump outlet is connected to the oil cooler inlet via a pipe, the oil cooler outlet is connected to the fine filter inlet via a pipe, and the fine filter outlet is connected to the oil inlets of the drive components on the left and right sides via two oil inlet pipes.

10. A centralized lubrication electric drive bridge according to claim 9, characterized in that: The cooling and lubrication system also includes an oil manifold plate located at the rear end of the axle housing. The coarse filter, fine filter, oil pump, and oil cooler are all fixedly mounted on the oil manifold plate. The oil manifold plate has internal channels connecting the coarse filter and the oil pump, the oil pump and the oil cooler, and the oil cooler and the fine filter.

Images