Dual-drive motor structure for electric drive axle

Abstract

The invention discloses a dual-drive motor structure for an electric drive axle, and relates to the technical field of dual-drive motors. Comprising a left motor used for providing left driving force; a stator structure and a rotor structure of the left motor adopt an oil cooling heat dissipation mode; the right motor is used for providing right driving force; a stator structure and a rotor structure of the right motor adopt an oil cooling heat dissipation mode; the transition disc is used for connecting the left motor and the right motor; the left brake is mounted on the left motor and used for providing braking torque and controlling the left motor to brake; the right brake is installed on the right motor and used for providing braking torque and controlling braking of the right motor. And the transition disc tightly couples the left and right motors, the clutch and the left and right brakes into a whole. The double-motor structure layout is adopted inside, driving force can be flexibly provided for the left wheel and the right wheel of the electric drive axle respectively or simultaneously, and the flexibility and the power distribution capacity of the driving system are enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of dual-drive motors, and in particular to a dual-drive integrated oil-cooled self-dissipating motor suitable for an electric drive axle of a heavy-duty vehicle. Background Art

[0002] The electric drive axle system is the core component of electric vehicles, and its technical level directly restricts the overall performance of the vehicle. The electric drive axle can be divided into rear-mounted rear-drive half-axle output, central drive system, coaxial / parallel axis electric drive axle, wheel-side electric drive axle, and hub electric drive axle. Among them, the parallel axis electric drive axle is widely used in heavy-duty vehicles, while the direct drive (with reducer) method is common in light truck design; the parallel axis electric drive axle is integrated with the traditional drive axle through the motor, and the motor directly drives the wheel after the torque is increased by the reducer. In addition, the use of independent motor drive for the wheel can simplify the mechanical transmission structure, reduce the weight of the vehicle body, and provide a flexible space layout; this solution not only enhances the drive anti-skid and dynamic stability control capabilities by precisely controlling the torque output of each wheel motor, but also significantly improves the vehicle's passability, stability and driving efficiency. It is an important development direction for heavy-duty electric drive vehicles.

[0003] However, the current parallel-axis electric drive axles generally adopt a single motor configuration and a three-section bridge housing design. The two ends of the motor are coaxially connected to the traditional drive axle. This three-section bridge housing fastened by bolts is bulky, heavy, low in integration, and has limited load-bearing capacity. It is also accompanied by noise and vibration problems, and the uneven weight distribution of the bridge body affects the handling. Single-motor drive is also prone to slippage, and the motor power density is insufficient, resulting in limited vehicle power performance, and the motor maintenance is complex and the heat dissipation effect is poor.

[0004] In addition, as a key component connecting the road surface and the frame, the electric drive axle needs to withstand complex and changeable mechanical loads, including plumb force, longitudinal force, lateral force and its torque. In addition, the large mass of the bridge body and the offset center of gravity of the vehicle directly pose challenges to the vehicle's safety, economy, comfort, reliability and handling performance. Summary of the invention

[0005] The object of the present invention is to provide a dual drive motor structure for an electric drive axle, which has the advantages of small size, compact structure, high motor power density, high heat dissipation efficiency, convenient maintenance, good protection, simple structure and good integration.

[0006] To achieve the above purpose, the technical solution of the present application is: a dual drive motor structure for an electric drive axle, comprising:

[0007] The left motor is used to provide left driving force; the stator structure and rotor structure of the left motor adopt oil cooling;

[0008] The right motor is used to provide right driving force; the stator structure and rotor structure of the right motor adopt oil cooling;

[0009] A transition plate, used to connect the left motor and the right motor;

[0010] The left brake is installed on the left motor and is used to provide a braking torque to control the braking of the left motor;

[0011] The right brake is installed on the right motor and is used to provide braking torque to control the braking of the right motor.

[0012] The present invention adopts the above technical solution, and can achieve the following technical effects:

[0013] 1. The transition plate tightly couples the left and right motors, clutches and left and right brakes into a whole. The internal dual-motor structure layout can flexibly provide driving force for the left and right wheels of the electric drive bridge separately or simultaneously, enhancing the flexibility and power distribution capabilities of the drive system.

[0014] 2. In order to increase the service life of the motor bearings and reduce maintenance costs, the bearings on both sides of the motor adopt an oil-cooled lubrication structure and use high-speed ball bearings. This design effectively reduces the friction resistance of the bearings, extends the service life of the bearings, and extends the maintenance cycle of the motor.

[0015] 3. In order to improve the power density and heat dissipation efficiency of the motor, the motor stator and rotor structure adopts oil cooling; at the same time, a centrifugal impeller is integrated inside the motor to provide continuous pressure for the cooling oil, so that the motor has self-cooling ability. This not only improves the heat dissipation efficiency of the motor, but also further improves the integration and performance of the drive motor.

[0016] 4. The left and right motors are equipped with brakes independently, which enables the drive axle to have additional electromagnetic braking capabilities and provide a separate braking torque for the vehicle. This helps to shorten the braking distance of the vehicle and improve safety and stability during driving.

[0017] 5. A clutch is installed on the transition plate, which can flexibly couple the left and right motors together to achieve dual-axis synchronous output. This function can effectively prevent the wheels from slipping during vehicle driving, and improve the vehicle's controllability and stability under various road conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 It is a cross-sectional view of the structure of the dual drive motor for the electric drive axle;

[0020] Figure 2 is a cross-sectional view of the stator structure of the left motor;

[0021] Figure 3 is a cross-sectional view of the stator structure of the right motor;

[0022] Figure 4 is a cross-sectional view of the rotor structure of the left motor;

[0023] Figure 5 The end view of the rotor structure of the left or right motor;

[0024] Figure 6 This is a schematic diagram of the transition plate position connection.

[0025] Explanation of the numbers in the figure: 1. Left housing; 2. Left stator core with winding; 3. M oil guide pipe; 4. Rotor structure of left motor; 5. Rotor oil outlet pipe; 6. Right stator core with winding; 7. Waterproof connector; 8. Right terminal box; 9. Power terminal of right motor; 10. Right end cover; 11. Right bearing inner cover; 12. Right reluctance rotary transformer; 13. Rotating shaft; 14. Right outer oil seal; 15. Right bearing outer cover; 16. Left self-locking retaining spring; 17. Right drive end ball bearing; 18. Right brake end ball bearing; 19. Right self-locking retaining spring; 20. Right centrifugal impeller; 21. Left centrifugal impeller; 22. Left brake end ball bearing; 23. Left bearing inner cover; 24. Left drive end ball bearing; 25 , left bearing outer cover; 26, left outer oil seal; 27, left reluctance rotary transformer; 28, left end cover; 29, left motor power terminal; 30, left inner oil seal; 31, left oil suction pipe; 32, left brake; 33, toothed disc; 34, right brake; 35, left spline sleeve; 36, transition plate; 37, right spline sleeve; 38, right brake end bearing outer cover; 39, left brake end bearing outer cover; 40, stator oil outlet pipe; 41, three-phase lead wire; 42, left annular oil channel; 43, left oil inlet; 44, left first row of oil holes; 45, left first injection hole; 46, stator punching plate; 47, left oil storage chamber; 48, stator coil; 49, stator slot wedge; 50, left second row of oil holes; 51, left Brake end cover; 52, pump chamber of left brake end cover; 53, bearing chamber of left brake end cover; 54, left second oil injection hole; 55, stator pressure ring; 56, oil drain hole of left end cover; 57, oil outlet chamber of left brake end cover; 58, oil passage; 59, right first oil injection hole; 60, right oil inlet; 61, bearing chamber of right brake end cover; 62, pump chamber of right brake end cover; 63, right brake end cover; 64, right first oil drain hole; 65, right oil storage chamber; 66, right second oil injection hole; 67, right second oil drain hole; 68, right annular oil passage; 69, oil outlet chamber of right brake end cover; 70, oil drain hole of right end cover; 71, adjustment washer; 72, rear rotor pressure ring; 73, magnetic Steel; 74, rotor punching plate; 75, front rotor pressure ring; 76, rotor bracket; 77, R-type piston expansion ring; 78, annular groove S; 79, annular groove H; 80, annular groove K; 81, annular groove G; 82, radial oil passage C; 83, radial oil passage C'; 84, radial oil passage D; 85, radial oil passage D'; 86, axial oil passage E; 87, axial oil passage E'; 88, axial oil passage F; 89, axial oil passage F'; 90, flat key; 91, clutch; 92, left spline sleeve motor side external teeth; 93, right spline sleeve clutch side external teeth; 94, external tooth diaphragm; 95, internal tooth diaphragm; 96, oil storage channel; 97, oil hole channel L1; 98, oil hole channel L2. DETAILED DESCRIPTION

[0026] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0027] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0028] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "multiple" means two or more, unless otherwise clearly and specifically defined. "Several" means one or more, unless otherwise clearly and specifically defined.

[0029] In the description of the present application, it should be understood that the terms "center", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0030] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0031] like Figure 1 As shown, this embodiment provides a dual drive motor structure for an electric drive axle, including:

[0032] The left motor is used to provide left driving force; the stator structure and rotor structure of the left motor adopt oil cooling;

[0033] The right motor is used to provide right driving force; the stator structure and rotor structure of the right motor adopt oil cooling;

[0034] A transition plate, used to connect the left motor and the right motor;

[0035] The left brake is installed on the left motor and is used to provide a braking torque to control the braking of the left motor;

[0036] The right brake is installed on the right motor and is used to provide braking torque to control the braking of the right motor.

[0037] In one embodiment, if Figure 2 As shown, the stator structure of the left motor includes:

[0038] The left casing, as the stator shell of the left motor, can be welded from high-quality alloy structural steel or aluminum alloy; a left annular oil passage and a left oil storage chamber are provided on the left casing, wherein the left annular oil passage has a left oil inlet, a left first oil injection hole, and a left second oil injection hole, wherein the left oil inlet is connected to the M oil guide pipe; the left oil storage chamber is connected to the inner cavity of the motor through the left first oil discharge hole and the left second oil discharge hole, and the cooling oil of the inner cavity of the motor can be discharged to the left oil storage chamber, and the left oil storage chamber is provided with an oil drain hole to discharge the cooling oil; preferably, the left first oil discharge hole and the left second oil discharge hole are circumferentially distributed on the inner circular surface of the left casing, and a plurality of them are arranged near the end of the stator winding. After the cooling oil is discharged from the oil discharge hole, the cooling oil is sprayed on the end of the stator winding, and the cooling oil adheres to the winding and the side wall to take away its heat, thereby dissipating heat for the stator winding;

[0039] The left stator core with windings is interference fit with the left casing; the left stator core of the present invention is formed by laminating stator punching sheets and stator pressing rings, and the lamination method adopts an external pressing process. After lamination, the stator windings are embedded in the stator core slots, the coils are fixed with stator slot wedges, and the inter-pole connection lines are connected as required. Finally, the stator core with windings is installed in the left casing, and the three-phase lead wires of the stator coils are led from the casing outlet to the left motor power terminal, and the left motor power terminal is located in the left terminal box, and a waterproof plug is provided on the left terminal box; it should be noted that the stator coil can be selected from scattered windings and flat wire windings; in addition, if there are special needs, the power of the left and right motors can be changed;

[0040] The left brake end cover is welded with the left casing to form an integrated structure, which can increase the rigidity of the casing and reduce noise and vibration. The left brake end cover is provided with a bearing chamber and a pump chamber. The left centrifugal impeller is placed in the pump chamber. The centrifugal impeller delivers cooling oil to the oil outlet chamber of the left brake end cover. The cooling oil flows through the stator oil outlet pipe into the M oil guide pipe, enters the left annular oil channel from the left oil inlet, and enters the right annular oil channel from the right oil inlet.

[0041] like Figure 3 As shown, the stator structure of the right motor includes:

[0042] The right casing, as the right motor stator shell, can be welded with high-quality alloy structural steel or aluminum alloy; a right annular oil passage and a right oil storage chamber are opened on the right casing, the right annular oil passage has a right oil inlet, a right first oil injection hole, and a right second oil injection hole, wherein the right oil inlet is connected with the M oil guide pipe; the right oil storage chamber is connected with the inner cavity of the motor through the right first oil discharge hole and the right second oil discharge hole, and the cooling oil in the inner cavity of the motor can be discharged to the right oil storage chamber, and the right oil storage chamber is provided with an oil drain hole to discharge the cooling oil; preferably, the right first oil discharge hole and the right second oil discharge hole are circumferentially distributed on the inner circular surface of the right casing, and a plurality of them are arranged near the end of the stator winding. After the cooling oil is discharged from the oil discharge hole, the cooling oil is sprayed on the end of the stator winding, and the cooling oil adheres to the winding and the side wall to take away its heat, thereby dissipating heat for the stator winding;

[0043] The right stator core with windings is interference fit with the left casing; the right stator core of the present invention is formed by laminating stator punching sheets and stator pressing rings, and the lamination method adopts an external pressing process. After lamination, the stator windings are embedded in the stator core slots, the coils are fixed with stator slot wedges, and the inter-pole connection lines are connected as required. Finally, the stator core with windings is installed in the right casing, and the three-phase lead wires of the stator coils are led from the casing outlet to the right motor power terminal, and the right motor power terminal is located in the right terminal box, and a waterproof plug is provided on the right terminal box; it should be noted that the stator coils can be selected from scattered windings and flat wire windings; in addition, if there are special needs, the power of the left and right motors can be changed;

[0044] The right brake end cover is welded with the right casing to form an integral structure, which can increase the rigidity of the casing and reduce noise and vibration. A bearing chamber and a pump chamber are provided on the right brake end cover. The right centrifugal impeller is placed in the pump chamber. The centrifugal impeller delivers cooling oil to the oil outlet chamber of the right brake end cover. The cooling oil flows through the rotor oil outlet pipe and enters the oil passage.

[0045] In one embodiment, if Figure 4 As shown, the rotor structure of the left motor and the rotor structure of the right motor both include:

[0046] The rotating shaft has an oil inlet hole a in the axial direction and oil outlet holes b, c, d and e in the radial direction; an R-type piston sealing ring is sleeved on the rotating shaft;

[0047] The rotor bracket adopts interference fit with the rotating shaft; an annular groove S and an annular groove H are provided on the inner ring of the rotor bracket, wherein the annular groove S is communicated with the oil outlet hole c, and the annular groove H is communicated with the oil outlet hole b; Figure 5As shown, radial oil passages C, C', D, D', axial oil passages E, E', F and F' are also provided on the inner ring of the rotor support, wherein radial oil passages C and C' are in communication with the annular groove S, axial oil passage E is in communication with radial oil passage C, and axial oil passage E' is in communication with radial oil passage C'; wherein radial oil passages D and D' are in communication with the annular groove H, axial oil passage F is in communication with radial oil passage D, and axial oil passage F' is in communication with radial oil passage D';

[0048] The rotor core is clamped with the rotor bracket shoulder; the rotor core is formed by laminating rotor punchings, and magnetic steel slots are opened on the rotor punchings. After laminating, the magnetic steel is embedded in the magnetic steel slots according to the magnetic pole sequence. The rotor punchings and the rotor bracket are positioned and torque is transmitted by flat keys, and the outer circle of the rotor bracket is matched with the inner circle of the rotor core;

[0049] The front rotor pressing ring and the rear rotor pressing ring are arranged on both sides of the rotor core, and are clamped with the rotor bracket shoulder and adopt interference fit; the front rotor pressing ring is provided with a connected oil injection hole g and an annular groove K, and the annular groove K is communicated with the axial oil passage F and the axial oil passage F'; the rear rotor pressing ring is provided with a connected oil injection hole f and annular groove G, and the annular groove G is communicated with the axial oil passage E and the axial oil passage E'; the gap between the rear rotor pressing ring and the rotor bracket retaining ring groove is adjusted with an adjusting washer, and finally the left self-locking retaining ring and the right self-locking retaining ring are used for axial positioning;

[0050] The rotor oil passage of the present invention is divided into two routes, one of which is acSCE (C'-E')-Gf and the other is abHDF (D'-F')-Kg.

[0051] In one embodiment, the driving bearing structure of the left motor includes:

[0052] The left drive end ball bearing, whose outer ring is in matching contact with the inner circle of the left end cover bearing chamber, and whose inner ring is in matching contact with the outer circle of the bearing stopper at the drive end of the rotating shaft of the left motor;

[0053] The left bearing inner cover and the left bearing outer cover are respectively located on both sides of the left end cover, and the three of them form the left drive bearing chamber; the oil outlet e located at the driving end of the rotating shaft of the left motor sprays the cooling oil into the bearing chamber, and there is a labyrinth gap between the left bearing inner cover and the rotating shaft to ensure that a certain amount of cooling oil is stored in the bearing chamber. An oil drain hole is provided on the lower side of the left end cover to allow the cooling oil for lubricating the bearing to flow continuously, so that a steady stream of new cooling oil will enter the bearing chamber, and the oil drain hole will discharge the cooling oil with heat to ensure that the motor bearing runs well under high load operation; a left outer oil seal is provided between the left bearing outer cover and the rotating shaft to ensure that the cooling oil will not leak or be contaminated;

[0054] The left reluctance rotary transformer is arranged outside the ball bearing at the left driving end and is used to monitor the rotor position and control the speed of the motor; the outer ring of the left reluctance rotary transformer is clamped with the outer stopper of the left end cover, and the inner ring is clamped with the rotating shaft;

[0055] The driving bearing structure of the right motor comprises:

[0056] The right drive end ball bearing, whose outer ring is in matching contact with the inner circle of the right end cover bearing chamber, and whose inner ring is in matching contact with the outer circle of the bearing block of the right motor shaft drive end;

[0057] The right bearing inner cover and the right bearing outer cover are respectively located on both sides of the right end cover, and the three of them form the right drive bearing chamber; the oil outlet hole e located at the driving end of the rotating shaft of the right motor sprays the cooling oil into the bearing chamber, and there is a labyrinth gap between the right bearing inner cover and the rotating shaft to ensure that the bearing chamber stores a certain amount of cooling oil. An oil drain hole is provided on the lower side of the right end cover to allow the cooling oil for lubricating the bearing to flow continuously, so that a steady stream of new cooling oil will enter the bearing chamber, and the oil drain hole will discharge the cooling oil with heat to ensure that the motor bearing runs well under high load operation; a right outer oil seal is provided between the right bearing outer cover and the rotating shaft to ensure that the cooling oil will not leak or be contaminated;

[0058] The right reluctance rotary transformer is arranged outside the ball bearing at the right driving end and is used to monitor the rotor position and control the speed of the motor. The outer ring of the right reluctance rotary transformer is clamped with the outer stop of the right end cover, and the inner ring is clamped with the rotating shaft.

[0059] It should be noted that multiple O-rings are provided on each end cover of the motor to ensure the sealing of the motor and the cleanliness of the cooling oil. The bearing of the present invention completely relies on the cooling oil for lubrication and heat dissipation. When the motor is running at high speed, the cooling oil reduces the friction resistance and improves the heat dissipation of the bearing. It can be maintained together with the whole vehicle. This method not only improves the life of the bearing, but also eliminates the need for daily oiling and maintenance operations.

[0060] In one embodiment, the brake end bearing structure of the left motor includes:

[0061] The left brake end ball bearing, whose outer ring matches with the inner circle of the bearing chamber of the left brake end cover, and whose inner ring matches with the outer circle of the bearing stopper of the brake end of the rotating shaft of the left motor;

[0062] The left brake end bearing outer cover, which together with the left brake end cover, the left centrifugal impeller and the rotating shaft form a centrifugal oil pump to provide kinetic energy for the cooling oil; an oil inlet is provided at the lower part of the left brake end bearing outer cover, and the oil inlet is connected to a left oil suction pipe, and the left oil suction pipe extends into the left oil storage chamber oil; in the present invention, a left inner oil seal is installed between the left brake end bearing outer cover and the rotating shaft to seal the pump chamber, and when the motor is rotating, the left centrifugal impeller rotates driven by the rotor structure, and the left oil suction pipe sucks the cooling oil from the left oil storage chamber into the pump chamber, and after the left centrifugal impeller sends the cooling oil to the oil outlet chamber of the left brake end cover, the cooling oil flows through the stator oil outlet pipe and is sent to the left annular oil channel and the right annular oil channel through the M oil guide pipe to dissipate heat for the left and right motor stator structures;

[0063] The brake end bearing structure of the right motor includes:

[0064] The right brake end ball bearing, whose outer ring is matched with the inner circle of the bearing chamber of the right brake end cover, and whose inner ring is matched with the outer circle of the bearing block of the brake end of the rotating shaft of the right motor;

[0065] The right brake end bearing outer cover, together with the right brake end cover, the right centrifugal impeller and the rotating shaft, forms a centrifugal oil pump to provide kinetic energy for the cooling oil; an oil inlet is provided at the lower part of the right brake end bearing outer cover, and the oil inlet is connected to a right oil suction pipe, and the right oil suction pipe extends into the right oil storage chamber oil; in the present invention, a right inner oil seal is installed between the right brake end bearing outer cover and the rotating shaft to close the pump chamber, and when the motor is rotating, the right centrifugal impeller rotates driven by the rotor structure, and the right oil suction pipe sucks the cooling oil from the right oil storage chamber into the pump chamber. After the right centrifugal impeller delivers the cooling oil to the oil outlet chamber of the right brake end cover, the cooling oil flows through the rotor oil outlet pipe to the oil passage, passes through the oil hole channel of the transition plate, and is finally delivered to the oil inlet hole a of the rotating shaft of the left and right motors to cool and dissipate heat for the rotor structure.

[0066] In one embodiment, the left brake is installed on the mounting position of the left brake end bearing outer cover, the left brake is composed of multiple groups of diaphragms, the outer tooth diaphragm of the left brake is connected with the inner teeth of the left brake base, the inner tooth diaphragm is coupled with the outer teeth of the left spline sleeve motor side, the inner spline of the left spline sleeve is matched with the outer spline of the left motor brake end, and the left brake execution interface is connected to the external control mechanism of the motor;

[0067] The right brake is installed on the mounting position of the right brake end bearing outer cover. The right brake is composed of multiple groups of diaphragms. The outer tooth diaphragm is connected to the inner teeth of the right brake base, the inner tooth diaphragm is coupled to the outer teeth on the motor side of the right spline sleeve, the inner spline of the right spline sleeve cooperates with the outer spline of the right motor brake end, and the right brake execution interface is connected to the external control mechanism of the motor.

[0068] In one embodiment, if Figure 6As shown, a clutch is installed on the transition plate, which is used to couple the left and right motors together for dual-axis synchronous output to prevent wheel slippage; the clutch includes: inner-toothed diaphragms and outer-toothed diaphragms arranged alternately, wherein the inner-toothed diaphragms are coupled with the outer teeth on the clutch side of the left and right spline sleeves, and the outer-toothed diaphragms are coupled with the inner teeth of the gear plate, and the gear plate is provided with an R-type piston expansion ring, which cooperates with the inner circles of the left and right spline sleeves to prevent cooling oil leakage; when the clutch execution interface receives a control signal, the inner-toothed diaphragm is coupled with the outer-toothed diaphragm, so that the left and right spline sleeves are connected together, and since the left and right spline sleeves are connected with the outer splines on the brake ends of the left and right motors, the synchronous output of the dual motors of the electric drive bridge is realized.

[0069] In one embodiment, the transition plate is provided with an oil storage channel, an oil hole channel L1, and an oil hole channel L2. The cooling oil flowing out from the oil passage passes through the oil hole channel L1 and the oil hole channel L2 and enters the center hole of the gear plate, and then flows to the oil inlet hole a of the shaft of the left motor through the center channel L3 of the left spline sleeve, and flows to the oil inlet hole a of the shaft of the right motor through the center channel L4 of the right spline sleeve, so as to provide cooling oil for the rotor. The oil storage channel is used to connect the left and right oil storage chambers.

[0070] In one of the embodiments, the cooling oil entering the left annular oil passage is sprayed out from the left first oil injection hole and the left second oil injection hole, and the cooling oil enters the left oil storage chamber from the left first oil row hole and the left second oil row hole under the action of gravity; the cooling oil entering the right annular oil passage is sprayed out from the right first oil injection hole and the right second oil injection hole, and the cooling oil enters the right oil storage chamber from the right first oil row hole and the right second oil row hole under the action of gravity.

[0071] In one of the embodiments, the cooling oil delivered to the oil inlet hole a of the rotating shaft is sprayed out from the oil hole g of the front rotor pressure ring and the oil hole f of the rear rotor pressure ring, respectively, and sprayed on the end of the stator coil and around the casing to dissipate heat; the cooling oil enters the left oil storage chamber from the left first oil row hole and the left second oil row hole under the action of gravity, and enters the right oil storage chamber from the right first oil row hole and the right second oil row hole; the left and right oil storage chambers are respectively located at the lower part of the left and right motors, and the left and right motors are located at the lower part of the vehicle body, and form convection with the air when the vehicle is running to dissipate heat for the cooling oil in the left and right oil storage chambers, and the cooling oil after heat dissipation is re-inhaled into the centrifugal oil pump, and the motor is circulated and dissipated according to the oil route, and no external equipment is required to provide kinetic energy for the coolant. In addition, heat dissipation ribs are provided on the outside of the motor casing to improve the heat dissipation efficiency, strengthen the mechanical strength of the casing, and reduce the weight of the motor, so that the electric drive axle dual drive motor has a high degree of integration.

[0072] The present invention is different from the general electric drive axle motor structure. The stator adopts an oil-cooled spray heat dissipation structure. The motor brake end cover and the casing are integrated into a whole. On the one hand, it can be used to support the motor rotor. On the other hand, it can strengthen the casing strength and improve the overall rigidity of the electric drive axle. The motor casing is provided with an oil inlet, an oil drain port, and an oil storage chamber. The brake end cover is built with a centrifugal impeller. The impeller is installed on the rotor and together with the outer cover forms a centrifugal oil pump to provide kinetic energy for the cooling oil. The motor rotor adopts oil-cooled spray technology. The cooling oil flows through the rotor and sprays out from the front and rear rotor pressure rings to dissipate heat for the stator winding end. The motor bearings all adopt an oil lubrication structure. An oil inlet and outlet are provided near the bearing chamber to provide circulating cooling oil for the bearings, which fully lubricates and cools the bearings. Brakes are installed on the outer end covers of the left and right motor brake ends to provide braking torque for each motor separately. The electric drive axle integrates the left motor by a transition plate, and the transition plate is provided with a clutch and an oil through hole, which connects the left and right motors in series, so that the electric drive axle not only has the ability of dual-axis common output, but also has the ability of oil cooling and self-cooling.

[0073] The dual-drive motor structure for an electric drive axle of the present invention can be applied to electric drive transportation equipment such as heavy-duty locomotives, articulated trucks, loaders, wide-body vehicles, and automobile mining dump trucks. Compared with the previous electric drive axle motors, it has the advantages of smaller size, compact structure, large motor power density, high heat dissipation efficiency, convenient maintenance, good protection, simple structure, and good integration. After the structure is applied to the electric drive axle, the volume of the electric drive axle can be reduced and the overall compactness can be improved. The wheel-side reduction devices can be directly installed on the left and right sides of the dual-drive motor structure for the electric drive axle. As an electric drive axle, it has a compact structure. The electric drive axle has the characteristics of high vehicle rigidity, high power density, and low noise and vibration. The dual-drive motor structure for the electric drive axle can also be applied to large-scale mining transportation equipment with more tonnage, improve transportation efficiency, reduce costs, and is beneficial to accelerate the development of heavy-duty transportation equipment and mining transportation vehicle industries. It is an important development direction for heavy-duty electric drive vehicles and plays an important role in promoting green new energy electric drive systems.

[0074] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A dual drive motor structure for an electric drive axle, characterized in that: include: The left motor is used to provide left driving force; the stator structure and rotor structure of the left motor adopt oil cooling; A right motor, used for providing right driving force; The stator and rotor structures of the right motor adopt oil cooling; A transition plate, used to connect the left motor and the right motor; The left brake is installed on the left motor and is used to provide a braking torque to control the braking of the left motor; The right brake is installed on the right motor and is used to provide braking torque to control the braking of the right motor.

2. According to claim 1, a dual drive motor structure for an electric drive axle is characterized in that: The stator structure of the left motor comprises: The left casing is used as the stator casing of the left motor; a left annular oil passage and a left oil storage chamber are formed on the left casing, wherein the left annular oil passage has a left oil inlet, a left first oil injection hole, and a left second oil injection hole, wherein the left oil inlet is connected to the M oil guide pipe; the left oil storage chamber is connected to the inner cavity of the motor through the left first oil discharge hole and the left second oil discharge hole; The left stator core with winding has an interference fit with the left casing; The left brake end cover is welded with the left casing to form an integral structure; a bearing chamber and a pump chamber are provided on the left brake end cover, and a left centrifugal impeller is placed in the pump chamber; The stator structure of the right motor comprises: The right casing is used as the stator casing of the right motor; a right annular oil passage and a right oil storage chamber are formed on the right casing, wherein the right annular oil passage has a right oil inlet, a right first oil injection hole, and a right second oil injection hole, wherein the right oil inlet is connected to the M oil guide pipe; the right oil storage chamber is connected to the inner cavity of the motor through the right first oil discharge hole and the right second oil discharge hole; The right stator core with windings has an interference fit with the left casing; The right brake end cover is welded with the right casing to form an integral structure; a bearing chamber and a pump chamber are provided on the right brake end cover, and a right centrifugal impeller is placed in the pump chamber.

3. The dual drive motor structure for an electric drive axle according to claim 1, characterized in that: The rotor structure of the left motor and the rotor structure of the right motor both include: The rotating shaft has an oil inlet hole a in the axial direction and oil outlet holes b, c, d and e in the radial direction; The rotor support adopts interference fit with the rotating shaft; an annular groove S and an annular groove H are provided on the inner ring of the rotor support, wherein the annular groove S is communicated with the oil outlet hole c, and the annular groove H is communicated with the oil outlet hole b; radial oil passages C, radial oil passages C', radial oil passages D, radial oil passages D', axial oil passages E, axial oil passages E', axial oil passages F, and axial oil passages F' are also provided on the inner ring of the rotor support, wherein the radial oil passages C and radial oil passages C' are communicated with the annular groove S, the axial oil passage E is communicated with the radial oil passage C, and the axial oil passage E' is communicated with the radial oil passage C'; wherein the radial oil passages D and radial oil passages D' are communicated with the annular groove H, the axial oil passage F is communicated with the radial oil passage D, and the axial oil passage F' is communicated with the radial oil passage D'; The rotor core is clamped with the rotor bracket shoulder; The front rotor pressure ring and the rear rotor pressure ring are arranged on both sides of the rotor core, and are clamped with the rotor bracket shoulder with interference fit; the front rotor pressure ring is provided with a connected oil injection hole g and an annular groove K, and the annular groove K is communicated with the axial oil passage F and the axial oil passage F'; the rear rotor pressure ring is provided with a connected oil injection hole f and annular groove G, and the annular groove G is communicated with the axial oil passage E and the axial oil passage E'.

4. The dual drive motor structure for an electric drive axle according to claim 3, characterized in that: The driving bearing structure of the left motor comprises: The left drive end ball bearing, whose outer ring is in matching contact with the inner circle of the left end cover bearing chamber, and whose inner ring is in matching contact with the outer circle of the bearing stopper at the drive end of the rotating shaft of the left motor; The left bearing inner cover and the left bearing outer cover are respectively located on both sides of the left end cover, and the three of them form the left drive bearing chamber; the oil outlet hole e located at the driving end of the rotating shaft of the left motor sprays the cooling oil into the bearing chamber, and there is a labyrinth gap between the left bearing inner cover and the rotating shaft to ensure that a certain amount of cooling oil is stored in the bearing chamber. An oil drain hole is provided on the lower side of the left end cover to make the cooling oil for lubricating the bearing flow continuously, so that a steady stream of new cooling oil will enter the bearing chamber, and the oil drain hole will discharge the cooling oil with heat; The left reluctance rotary transformer is arranged outside the ball bearing at the left driving end and is used to monitor the rotor position and control the speed of the motor; the outer ring of the left reluctance rotary transformer is clamped with the outer stopper of the left end cover, and the inner ring is clamped with the rotating shaft; The driving bearing structure of the right motor comprises: The right drive end ball bearing, whose outer ring is in matching contact with the inner circle of the right end cover bearing chamber, and whose inner ring is in matching contact with the outer circle of the bearing block of the right motor shaft drive end; The right bearing inner cover and the right bearing outer cover are located on both sides of the right end cover respectively, and the three of them form the right drive bearing chamber; the oil outlet hole e located at the driving end of the rotating shaft of the right motor sprays the cooling oil into the bearing chamber, and there is a labyrinth gap between the right bearing inner cover and the rotating shaft to ensure that a certain amount of cooling oil is stored in the bearing chamber. An oil drain hole is provided on the lower side of the right end cover to make the cooling oil for lubricating the bearing flow continuously, so that there will be a steady stream of new cooling oil entering the bearing chamber, and the oil drain hole will discharge the cooling oil with heat; The right reluctance rotary transformer is arranged outside the ball bearing at the right driving end and is used to monitor the rotor position and control the speed of the motor. The outer ring of the right reluctance rotary transformer is clamped with the outer stop of the right end cover, and the inner ring is clamped with the rotating shaft.

5. The dual drive motor structure for an electric drive axle according to claim 1, characterized in that: The brake end bearing structure of the left motor includes: The left brake end ball bearing, whose outer ring matches with the inner circle of the bearing chamber of the left brake end cover, and whose inner ring matches with the outer circle of the bearing stopper of the brake end of the rotating shaft of the left motor; The left brake end bearing outer cover has an oil inlet at its lower part, and the oil inlet is connected to a left oil suction pipe, and the left oil suction pipe extends into the left oil storage chamber oil; when the motor is rotating, the left centrifugal impeller rotates driven by the rotor structure, and the left oil suction pipe sucks the cooling oil from the left oil storage chamber into the pump chamber. After the left centrifugal impeller sends the cooling oil to the oil outlet chamber of the left brake end cover, the cooling oil flows through the stator oil outlet pipe and is sent to the left annular oil channel and the right annular oil channel through the M oil guide pipe to dissipate heat for the left and right motor stator structures; The brake end bearing structure of the right motor includes: The right brake end ball bearing, whose outer ring is matched with the inner circle of the bearing chamber of the right brake end cover, and whose inner ring is matched with the outer circle of the bearing block of the brake end of the rotating shaft of the right motor; The right brake end bearing outer cover has an oil inlet at the lower part, which is connected to a right oil suction pipe, and the right oil suction pipe extends into the right oil storage chamber oil; when the motor is rotating, the right centrifugal impeller rotates driven by the rotor structure, and the right oil suction pipe sucks the cooling oil from the right oil storage chamber into the pump chamber. After the right centrifugal impeller delivers the cooling oil to the oil outlet chamber of the right brake end cover, the cooling oil flows through the rotor oil outlet pipe to the oil passage, passes through the oil hole channel of the transition plate, and is finally delivered to the oil inlet hole a of the rotating shaft of the left and right motors to cool and dissipate heat for the rotor structure.

6. The dual drive motor structure for an electric drive axle according to claim 1, characterized in that: The left brake is installed on the mounting position of the left brake end bearing outer cover, the outer tooth diaphragm of the left brake is connected with the inner teeth of the left brake base, the inner tooth diaphragm is coupled with the outer teeth of the left spline sleeve motor side, and the inner spline of the left spline sleeve is matched with the outer spline of the left motor brake end; The right brake is installed on the mounting position of the right brake end bearing outer cover, the outer tooth diaphragm of the right brake is connected with the inner teeth of the right brake base, the inner tooth diaphragm is coupled with the outer teeth on the motor side of the right spline sleeve, and the inner spline of the right spline sleeve cooperates with the outer spline of the right motor brake end.

7. The dual drive motor structure for an electric drive axle according to claim 1, characterized in that: A clutch is installed on the transition plate, which is used to couple the left and right motors together for dual-axis synchronous output; the clutch includes: inner-toothed diaphragms and outer-toothed diaphragms arranged alternately, wherein the inner-toothed diaphragms are coupled with the outer teeth on the clutch sides of the left and right spline sleeves, and the outer-toothed diaphragms are coupled with the inner teeth of the gear plate; when the clutch execution interface receives a control signal, the inner-toothed diaphragm is coupled with the outer-toothed diaphragm, so that the left and right spline sleeves are connected together. Since the left and right spline sleeves are matched with the outer splines on the brake ends of the left and right motors, the synchronous output of the dual motors of the electric drive bridge is realized.

8. The dual drive motor structure for an electric drive axle according to claim 5, characterized in that: The transition plate is provided with an oil storage channel, an oil hole channel L1, and an oil hole channel L2. The cooling oil flowing out from the oil passage passes through the oil hole channel L1 and the oil hole channel L2 and enters the center hole of the gear plate, and then flows to the oil inlet hole a of the rotating shaft of the left motor through the center channel L3 of the left spline sleeve, and flows to the oil inlet hole a of the rotating shaft of the right motor through the center channel L4 of the right spline sleeve, so as to provide cooling oil for the rotor. The oil storage channel is used to connect the left and right oil storage chambers.

9. The dual drive motor structure for an electric drive axle according to claim 5, characterized in that: The cooling oil entering the left annular oil passage is sprayed out from the left first oil injection hole and the left second oil injection hole, and the cooling oil enters the left oil storage chamber from the left first oil row hole and the left second oil row hole under the action of gravity; the cooling oil entering the right annular oil passage is sprayed out from the right first oil injection hole and the right second oil injection hole, and the cooling oil enters the right oil storage chamber from the right first oil row hole and the right second oil row hole under the action of gravity.

10. The dual drive motor structure for an electric drive axle according to claim 5, characterized in that: The cooling oil delivered to the oil inlet hole a of the rotating shaft is sprayed out from the oil hole g of the front rotor pressure ring and the oil hole f of the rear rotor pressure ring respectively, and sprayed on the end of the stator coil and around the casing to dissipate the heat; under the action of gravity, the cooling oil enters the left oil storage chamber from the left first oil row hole and the left second oil row hole, and enters the right oil storage chamber from the right first oil row hole and the right second oil row hole; the left and right oil storage chambers are respectively located at the lower part of the left and right motors, and the left and right motors are located at the lower part of the vehicle body, and form convection with the air when the vehicle is running, so as to dissipate the heat for the cooling oil in the left and right oil storage chambers, and the cooling oil after the heat dissipation is re-sucked into the centrifugal oil pump.

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