Distributed wheel edge driving device based on outer rotor motor
By adopting an external rotor motor structure in the wheel-side motor and utilizing the stator and rotor cavity design, the axial length of the drive components is reduced, solving the problem of large space occupation of permanent magnet synchronous motors and achieving a more compact structure and higher space utilization.
Patent Information
- Application Number
- CN202423295796.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-30
- Publication Date
- 2025-12-26
- Estimated Expiration
- 2034-12-30
AI Technical Summary
In existing wheel-side motor drives, permanent magnet synchronous motors have a large axial dimension, which occupies interior space and affects space utilization.
An external rotor motor structure is adopted, which forms a second cavity on the stator and bends the rotor output end to form an open cavity to accommodate the reduction assembly and reduce the axial length of the drive assembly.
The axial dimension of the drive components has been shortened, making the overall structure more compact and increasing the interior space, while maintaining the motor power and improving transmission efficiency.
Smart Images
Figure CN223720657U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to passenger car technical field, concretely relates to a kind of distributed wheel edge drive device based on outer rotor motor. BACKGROUND
[0002] Distributed drive is a kind of driving mode of electric vehicle and hybrid vehicle, which realizes independent driving of each wheel by installing multiple motors at different positions of vehicle, compared with centralized drive system, distributed drive system has higher flexibility, efficiency and performance advantage.Distributed drive mainly includes drive unit integrated with motor and inverter, control and management system and suspension system, secondly, common electric vehicle driving mode is wheel edge motor drive, which is a kind of driving mode that integrates motor directly into wheel, the shortest power transmission path, reduces energy loss, optimizes in-car space.Common wheel edge motor is permanent magnet synchronous motor, which generates constant magnetic field using permanent magnet, generates rotating magnetic field through alternating current in stator winding, so that rotor and stator magnetic field rotate synchronously, which mainly includes stator, rotor and position sensor.
[0003] Existing wheel edge motor drive commonly uses permanent magnet synchronous motor drive speed reducer to drive each wheel independently, wherein the magnetic flux density generated by permanent magnet directly affects electromagnetic torque and power output of motor, therefore, to ensure power output of permanent magnet synchronous motor and axial installation of speed reducer, its axial dimension is generally larger, which increases the axial space occupation of wheel edge motor and reduces the utilization rate of in-car space. SUMMARY
[0004] The utility model shortens the axial dimension of permanent magnet synchronous motor in wheel edge motor drive, provides a kind of distributed wheel edge drive device based on outer rotor motor, and specific technical solutions are as follows:
[0005] The utility model includes: drive assembly for output power, the drive assembly includes coaxial stator and the rotor of cladding this stator, the second cavity is formed along the axial direction to the one end of the output end of the stator close to the rotor, the output end of the rotor is bent to form open cavity to the second cavity, and the outer side surface of the output end of the rotor is the side surface of the open cavity;And the speed reduction component is connected with the output end of drive assembly and is coaxial with drive assembly, at least a part of the speed reduction component is placed inside open cavity.
[0006] Further, the input end of the stator forms the first cavity along the axial direction, the axial length of the first cavity is less than the second cavity, and the axial change of the second cavity and the first cavity does not affect the relative area of the radial outer side surface of the stator and the radial inner side surface of the rotor;The bending size of the output end of the rotor increases with the increase of the axial length of the second cavity, and decreases with the decrease of the axial length of the second cavity.
[0007] Preferably, the rotor is internally formed with a third cavity for placing the stator, the rotor further comprises: a first rotating part close to the first cavity, an inner bottom surface of the first rotating part corresponding to the first cavity, and a radially inner surface of the first rotating part opposite to a radially outer surface of the stator; and a second rotating part close to the second cavity, the second rotating part being bent to form an open cavity towards the second cavity, and the second rotating part and the first rotating part forming a closed structure.
[0008] Preferably, an axial length of the first cavity and an axial length of the second cavity are in a ratio of 1 / 3-1 / 2; a single-side gap between the radially outer surface of the stator and the radially inner surface of the rotor is L, and 0mm
[0009] Preferably, the drive assembly further comprises: a fixed shaft connected with the stator and the speed reduction component respectively, the fixed shaft being coaxial with the stator, the rotor and the speed reduction component; a first bearing arranged between the stator and the first rotating part, an inner surface and an outer surface of the first bearing being connected with the radially outer surface of the stator and the radially inner surface of the first rotating part respectively; and a reinforcing rib formed on the radially inner surface of the second rotating part, an inner surface of the reinforcing rib being coaxial with the fixed shaft, and the inner surface of the reinforcing rib being formed with a spline in an axial direction for connecting with the speed reduction component.
[0010] Preferably, the speed reduction component is axisymmetric, and the speed reduction component comprises, in sequence along a power output direction: a planetary carrier, a sun gear, a planet gear, an internally toothed ring gear, an output flange and a cover plate, wherein an outer surface of the sun gear and an inner surface of the reinforcing rib form a spline structure, and the reinforcing rib is capable of driving the sun gear to rotate around the fixed shaft through the spline structure.
[0011] Preferably, the drive assembly further comprises: a housing coaxially connected with the stator, an inside of the housing being formed with a placing cavity with an open end, the drive assembly being placed in the placing cavity, the open end of the placing cavity allowing the speed reduction component to pass through, and the housing further comprising a second bearing arranged at the open end of the placing cavity, an inner surface of the second bearing being connected with an outer surface of the speed reduction component, and an outer surface of the second bearing being connected with an inner surface of the open end of the placing cavity, the second bearing and the speed reduction component forming a closed cavity in the placing cavity.
[0012] Preferably, the drive assembly further comprises: a limiting protrusion formed on an outer surface of the fixed shaft, an end surface of the limiting protrusion having a diameter greater than a diameter of the fixed shaft, and an axial side surface of the limiting protrusion being coincident with an axial end surface of the stator; an O-ring arranged at a coincident surface of the limiting protrusion and the stator, the O-ring being capable of blocking cooling oil in the third cavity from flowing into a coincident position of the limiting protrusion and the stator; and a rotor oil seal arranged in a gap between an inner surface of the rotor and an outer surface of the fixed shaft, the rotor oil seal being capable of limiting cooling oil in the third cavity from flowing into the gap between the rotor and the fixed shaft.
[0013] According to the above technical solution, the utility model has the following beneficial effects:
[0014] The utility model discloses a stator and rotor that are formed with a second cavity, a second rotating member that forms an open cavity for placing a speed reduction assembly, and a middle region of the driving assembly has a reduced axial length. BRIEF DESCRIPTION OF DRAWINGS
[0015] Figure 1 It is the structure schematic diagram of the utility model embodiment;
[0016] Figure 2 It is the longitudinal section view of the utility model embodiment;
[0017] Figure 3 It is the cross section view of the driving assembly in the utility model;
[0018] Figure 4 It is the partial close -up view of B in the utility model; Figure 3
[0019] Figure 5 It is the cross section view of the speed reduction assembly in the utility model;
[0020] Figure 6 It is the partial close -up view of A in the utility model. Figure 2
[0021] In the drawing: 1, driving assembly;11, open cavity;12, fixed shaft: 13, stator;131, first cavity;132, second cavity;14, rotor;141, third cavity;142, first rotating member;143, second rotating member;15, first bearing;16, reinforcing rib;17, limit protruding;18, O ring;19, rotor oil seal;2, speed reduction assembly;21, planet carrier;22, sun gear;23, planet gear;24, inner tooth ring gear;25, output flange;26, cover plate;3, shell;31, place cavity;32, second bearing. DETAILED DESCRIPTION
[0022] The technical solutions in the embodiments of the utility model will be described clearly and completely below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the utility model.
[0023] In the description of the embodiments of the utility model, it needs to be explained that the directions or position relations indicated by the terms "inner", "outer", "upper" and the like are based on the directions or position relations shown in the drawings, or are the directions or position relations in which the utility model product is usually placed during use, and are only for the convenience of describing the utility model and simplifying the description, and thus cannot be understood as indicating or implying that the devices or elements referred to must have a specific direction, be constructed and operated in a specific direction, and thus cannot be understood as limiting the utility model.
[0024] As Figure 1 and Figure 2 shown, the embodiment comprises: a driving assembly 1 for outputting power, the driving assembly 1 comprising a stator 13 and a rotor 14 coaxially covering the stator 13, the stator 13 being formed with a second cavity 132 in the axial direction at one end close to the output end of the rotor 14, the output end of the rotor 14 being bent to form an open cavity 11 towards the second cavity 132, the side surface of the open cavity 11 being the outer side surface of the output end of the rotor 14; and a speed reduction assembly 2 coaxial with the driving assembly 1 and connected to the output end of the driving assembly 1, at least a part of the speed reduction assembly 2 being placed inside the open cavity 11.
[0025] Specifically, the driving assembly 1 is a permanent magnet synchronous motor, the stator 13 of which is fixed inside the rotor 14, so that the inner surface of the rotor 14 is always opposite to the outer surface of the stator 13 during the rotation of the rotor 14 around the stator 13, wherein the left end of the rotor 14 is a power input end, and the right end of the rotor 14 is a torque and rotational speed output end; secondly, the right end of the stator 13 is formed with a second cavity 132 having an open end, so that the axial length of the stator 13 around the four sides is greater than the axial length of the middle region of the stator 13, and the right end of the rotor 14 is bent towards the second cavity 132, so that the inner side surfaces thereof are respectively parallel to the side surfaces of the second cavity 132, and since the wall thickness of the right end of the rotor 14 is uniform, which is 10mm in the embodiment, the outer side surface of the right end thereof is bent, thereby forming an open cavity 11, so that the axial length of the rotor 14 around the four sides is greater than the axial length of the middle region of the rotor 14, and after the input end of the speed reduction assembly 2 is fixedly connected to the right end of the rotor 14, the input end of the speed reduction assembly 2 can be embedded in the open cavity 11, thereby reducing the axial length of the driving assembly 1 and the speed reduction assembly 2 as a whole, reducing the axial size of the embodiment, and making the structure of the embodiment more compact, thereby increasing the interior space of the new energy passenger vehicle.
[0026] As Figure 3As shown, the input end of the stator 13 forms a first cavity 131 in the axial direction, the axial length of the first cavity 131 is less than that of the second cavity 132, and the axial change of the first cavity 131 and the second cavity 132 does not affect the relative area of the radially outer side of the stator 13 and the radially inner side of the rotor 14; the bending size of the output end of the rotor 14 increases with the increase of the axial length of the second cavity 132, and decreases with the decrease of the axial length of the second cavity 132.
[0027] As known from common knowledge, the stator 13 includes a core and a winding, and the winding is arranged at the edge of the core. In the embodiment, the positional relationship between the core and the winding is unchanged, and the area of the winding relative to the radially inner side of the rotor 14 is unchanged, so that the area of the region where the alternating magnetic field generated by the stator 13 acting on the fixed magnetic field generated by the permanent magnet of the rotor 14 is unchanged, thereby the power of the driving assembly 1 does not decrease, but the right end of the middle region of the core forms the second cavity 132, the left end forms the first cavity 131, and the axial length of the first cavity 131 is less than that of the second cavity 132, so that the right end of the stator 13 can form the second cavity 132 with a larger volume without affecting the power of the motor, thereby the right end of the rotor 14 can form the open cavity 11 with an inward groove, thereby reducing the axial length of the middle region of the driving assembly 1, and further reducing the overall axial size.
[0028] Secondly, the first cavity 131 can separate the stator 13 from the left end of the rotor 14, so that the rotor 14 does not scratch when rotating around the stator 13, and a certain amount of cooling liquid can be stored.
[0029] Secondly, the inner side surface of the right end of the rotor 14 is parallel to the surface of the right end of the stator 13, and the bending direction of the right end of the stator 13 is the same as that of the right end of the stator 13, thereby forming the open cavity 11 for placing the speed reduction assembly 2, the axial length of the second cavity 132 is increased, and the inward bending degree of the rotor 14 is increased, so that the gap between the bottom surface of the second cavity 132 and the surface of the rotor 14 at the opposite position is maintained at 5mm, thereby not affecting the rotation of the rotor 14 around the stator 13, and the axial length of the open cavity 11 can be increased as much as possible, and further reducing the axial size of the embodiment.
[0030] Further, the inside of the rotor 14 forms a third cavity 141 for placing the stator 13, and the rotor 14 further includes: a first rotating part 142 close to the first cavity 131, the inner bottom surface of the first rotating part 142 corresponds to the first cavity 131, and the radially inner surface of the first rotating part 142 is opposite to the radially outer surface of the stator 13; and a second rotating part 143 close to the second cavity 132, the second rotating part 143 is bent towards the second cavity 132 to form the open cavity 11, and the second rotating part 143 and the first rotating part 142 form a stop structure.
[0031] Specifically, the first rotating part 142 and the second rotating part 143 are fixedly connected by bolts to form the rotor 14 capable of covering the stator 13, wherein the radially inner side of the first rotating part 142 is fixedly installed by permanent magnets, the axial length of the radially inner side determines the area of the alternating magnetic field of the permanent magnets acting on the stator 13, and further determines the rotating power of the driving assembly 1; secondly, the right end of the first rotating part 142 forms a threaded hole parallel to the axis, and the left side of the second rotating part 143 forms a threaded hole penetrating through, and then the second rotating part 143 is fixedly connected with the first rotating part 142 by bolts, wherein the edge of the second rotating part 143 forms a protrusion to coincide with the inner side of the right end of the first rotating part 142, and then the diameter of the protrusion of the second rotating part 143 is equal to the inner diameter of the inner side of the right end of the first rotating part 142, and then the second rotating part 143 limits its radial and axial degrees of freedom relative to the first rotating part 142 by the protrusion, that is, the stop structure, thereby improving the coaxiality of the second rotating part 143 and the first rotating part 142, and further improving the coaxiality of the open cavity 11 and the first rotating part 142, and further improving the coaxiality of the open cavity 11 and the stator 13, and further making the gaps between the radially outer side of the speed reduction assembly 2 and the radially inner side of the open cavity 11 all equal, thereby avoiding the eccentricity and vibration when the rotor 14 drives the speed reduction assembly 2 to rotate.
[0032] As shown in Figure 4 the axial length of the first cavity 131 and the axial length of the second cavity 132 are in a ratio of 1 / 3-1 / 2; the single-sided gap between the radially outer side of the stator 13 and the radially inner side of the rotor 14 is L, 0mm<L≦1mm.
[0033] Specifically, the first cavity 131 can store a certain amount of cooling liquid, and the second cavity 132 can reduce the axial size of the embodiment; in this embodiment, the wall thickness of the stator 13 is 10mm, when the ratio of the two is less than 1 / 3, the axial length of the second cavity 132 accounts for an increased axial length of the winding, so that the bending moment of the edge area of the core under the action of the magnetic field force increases, and further the structural strength of the stator 13 decreases, reducing the service life of the stator 13; when the ratio of the two is greater than 1 / 2, the axial length of the first cavity 131 accounts for an increased proportion of the axial length of the winding, and the axial length of the second cavity 132 accounts for a reduced proportion of the axial length of the winding, so that the axial length of the second cavity 132 is reduced, and further the axial length of the open cavity 11 is reduced, and further the axial size of the embodiment is increased.
[0034] Secondly, there must be a single-sided gap L between the stator 13 and the rotor 14, so that the rotor 14 can rotate around the stator 13, but when L>1mm, the magnetic field force between the stator 13 and the rotor 14 decreases, and the rotating power of the driving assembly 1 decreases.
[0035] Further, the driving assembly 1 further comprises a fixed shaft 12 connected with the stator 13 and the speed reduction component respectively, the fixed shaft 12 is coaxial with the stator 13, the rotor 14 and the speed reduction component, a first bearing 15 arranged between the stator 13 and the first rotating component 142, the inner side and the outer side of the first bearing 15 are connected with the radial outer side of the stator 13 and the radial inner side of the first rotating component 142 respectively, and a reinforcing rib 16 formed on the radial inner side of the second rotating component 143, the inner side of the reinforcing rib 16 is coaxial with the fixed shaft 12, and the inner side of the reinforcing rib 16 is formed in the axial direction and connected with the speed reduction assembly 2.
[0036] Specifically, the fixed shaft 12 is fixed in position, the left end of the fixed shaft 12 is in interference fit with the stator 13, and the left end of the fixed shaft 12 and the stator 13 are fixed with a sealing ring near the coincident area of the third cavity 141, so that the third cavity 141 forms a closed cavity, avoiding the leakage of the cooling liquid in the third cavity 141 through the connection gap between the fixed shaft 12 and the stator 13; secondly, the left end of the first rotating component 142 rotates around the left end of the stator 13 through the first bearing 15, and the radial inner side of the left end of the first rotating component 142 has a diameter not less than the inner ring diameter of the first bearing 15, so that after the first rotating component 142 is fixedly connected with the first bearing 15, it does not affect the rotation of the first rotating component 142 around the stator 13 through the first bearing 15, wherein the gap between the radial inner side of the left end of the first rotating component 142 and the radial outer side of the stator 13 is fixedly connected with an oil seal, so that the liquid in the third cavity 141 cannot leak through the gap of the first bearing 15.
[0037] Secondly, the radial inner side of the second rotating component 143 forms a spline, the length direction of the spline is the axial direction of the fixed shaft 12, and when the second rotating component 143 rotates relative to the fixed shaft 12, the spline rotates relative to the fixed shaft 12, in order to increase the contact area between the splines and reduce the pressure of the spline, the length of the reinforcing rib 16 is greater than the wall thickness of the second rotating component 143, at the same time, in order to ensure the volume of the open cavity 11, the reinforcing rib 16 protrudes towards the stator 13, thereby increasing the length of the spline, reducing the pressure between the splines when the second rotating component 143 drives the speed reduction assembly 2 to rotate, thereby reducing wear and tear, reducing the possibility of gaps between the splines due to long-term extrusion, and thereby improving the rotation efficiency.
[0038] Secondly, the left side of the spline is fixedly connected with an oil seal, avoiding the leakage of the liquid in the third cavity 141 through the gap between the splines, and the oil seals at the first bearing 15 and the spline and the sealing ring of the stator 13 and the first rotating component 142 form a closed cavity for the third cavity 141, improving the airtightness of the rotor 14, and thereby improving the cleanliness of the working environment.
[0039] As Figure 5As shown, the reduction assembly 2 is axisymmetric, and the reduction assembly 2 includes, in sequence along the power output direction, a planet carrier 21, a sun gear 22, a planet gear 23, an inner tooth ring gear 24, an output flange 25, and a cover plate 26. The outer side surface of the sun gear 22 is formed in a spline structure with the inner side surface of the reinforcing rib 16, and the reinforcing rib 16 can drive the sun gear 22 to rotate around the fixed shaft 12.
[0040] As known in the art, the planet carrier 21 is rotationally connected with the sun gear 22 and the planet gear 23, and can fix the position between the axes of the sun gear 22 and the planet gear 23. The sun gear 22 drives the planet gear 23 to rotate through the tooth groove, and the planet gear 23 drives the inner tooth ring gear 24 to rotate through the tooth groove.
[0041] Further, the planet carrier 21 is fixedly connected with the fixed shaft 12, so that the axes of the sun gear 22 and the planet gear 23 are fixed relative to the fixed shaft 12. The middle region of the sun gear 22 is formed with a through hole allowing the fixed shaft 12 to pass through. The radially outer side surface of the left end of the sun gear 22 is formed in a spline structure with the reinforcing rib 16, so that the reinforcing rib 16 can drive the sun gear 22 to rotate around the planet carrier 21, thereby driving the planet gear 23 and the inner tooth ring gear 24 to rotate. Further, the radially outer side surface of the right end of the inner tooth ring gear 24 is fixedly connected with the output flange 25, thereby driving the output flange 25 to rotate. The output flange 25 is connected with a tire (not shown in the figure) through the uniformly distributed threaded holes in the circumferential direction, thereby driving the tire to rotate. Further, the right end surface of the inner tooth ring gear 24 is flush with the protruding end surface of the output flange 25. The cover plate 26 is fixedly connected with the inner tooth ring gear 24 through bolts, and restricts the output flange 25 from moving rightward along the axial direction. The inner tooth ring gear 24 restricts the output flange 25 from moving leftward along the axial direction through the shaft protrusion, thereby keeping the radial and axial positions of the inner tooth ring gear 24 and the output flange 25 unchanged. When the inner tooth ring gear 24 drives the output flange 25 to rotate, there is no delay, thereby improving the transmission efficiency of the drive assembly 1.
[0042] Further, the embodiment also includes a housing 3 coaxially connected with the stator 13. The inside of the housing 3 is formed with a placement cavity 31 having an open end. The drive assembly 1 is placed in the placement cavity 31. The open end of the placement cavity 31 allows the reduction assembly 2 to pass through. The housing 3 also includes a second bearing 32 arranged at the open end of the placement cavity 31. The inner side surface of the second bearing 32 is connected with the outer side surface of the reduction assembly 2. The outer side surface of the second bearing 32 is connected with the inner side surface of the open end of the placement cavity 31. The second bearing 32 and the reduction assembly 2 form a closed cavity in the placement cavity 31.
[0043] Specifically, the rotor 14 can be wrapped by the stator 13, the shell 3 can wrap the rotor 14, and the inside of the shell 3 forms a placement cavity 31 for placing the rotor 14, and the right end of the placement cavity 31 forms an open end for allowing the ring gear 24 to pass through, wherein the radially outer side of the ring gear 24 is connected with the radially inner side of the open end of the shell 3 through the second bearing 32, so that the ring gear 24 can rotate around the shell 3, and the right end of the second bearing 32 is fixedly connected with an oil seal, which can completely seal the right end of the second bearing 32 and does not affect the rotation of the ring gear 24, so that the placement cavity 31 forms a sealed cavity.
[0044] As shown in Figure 6 The driving assembly further comprises a limiting protrusion formed on the outer side of the fixed shaft, the end face of the limiting protrusion is larger in diameter than the fixed shaft, and the axial side of the limiting protrusion coincides with the axial end face of the stator; an O-ring arranged on the coincident surface of the limiting protrusion and the stator, which can prevent the cooling oil in the third cavity from flowing into the coincident position of the limiting protrusion and the stator; and a rotor oil seal arranged in the gap between the inner side of the rotor and the outer side of the fixed shaft, which can limit the cooling oil in the third cavity from flowing into the gap between the rotor and the fixed shaft.
[0045] Specifically, the inner side of the stator and the outer side of the fixed shaft are in interference fit to seal the third cavity, but the cooling oil in the third cavity can flow into the third cavity through the gap at the connection position of the right end of the stator and the fixed shaft, the right end of the stator forms a small groove at the connection position, and the fixed shaft forms a limiting protrusion at the position, so that the limiting protrusion can be embedded in the small groove, which can not only limit the rightward movement of the stator relative to the fixed shaft, but also change the coincident surface of the right end connection position of the stator and the fixed shaft into a zigzag design; secondly, the O-ring is made of rubber material, which can seal the radially outer side of the limiting protrusion and the radially inner side of the small groove through elastic deformation, further limiting the cooling oil from flowing out through this position, and improving the sealing performance of the third cavity; secondly, there is a gap between the radially inner side of the right end of the rotor and the outer side of the fixed shaft for connecting the speed reducer, which makes the speed reducer communicate with the third cavity, reducing the sealing performance of the third cavity, and the gap is provided with a rotor oil seal, which seals the gap through elastic deformation, so that the third cavity is isolated from the speed reducer, thereby avoiding the oil in the speed reducer from entering the third cavity to pollute the cooling oil, or the cooling oil from flowing out of the third cavity to reduce the cooling effect of the rotor.
[0046] Although the embodiments of the present application have been shown and described, it should be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.
[0047] The utility model discloses a kind of technical, shape, configuration parts not described in detail are well-known technology.
Claims
1. A distributed wheel drive device based on an external rotor electric motor, characterized by The application relates to a distributed wheel drive device, which comprises: a driving assembly (1) for outputting power, the driving assembly (1) comprising a coaxial stator (13) and a rotor (14) covering the stator (13), the stator (13) being formed with a second cavity (132) at one end close to an output end of the rotor (14) in an axial direction, the output end of the rotor (14) being bent to form an open cavity (11) towards the second cavity (132), and the outer side of the output end of the rotor (14) being the side of the open cavity (11); and a speed reduction assembly (2) coaxial with the driving assembly (1) and connected with the output end of the driving assembly (1), at least a part of the speed reduction assembly (2) being arranged inside the open cavity (11).
2. The distributed wheel drive device according to claim 1, wherein: the input end of the stator (13) is formed with a first cavity (131) in the axial direction, the axial length of the first cavity (131) being smaller than that of the second cavity (132), and the axial change of the second cavity (132) and the first cavity (131) does not affect the relative area of the radial outer side of the stator (13) and the radial inner side of the rotor (14); the bending size of the output end of the rotor (14) increases with the increase of the axial length of the second cavity (132) and decreases with the decrease of the axial length of the second cavity (132).
3. The distributed wheel drive apparatus according to claim 2, characterized by: the inside of the rotor (14) is formed with a third cavity (141) for arranging the stator (13), and the rotor (14) further comprises: a first rotating part (142) close to the first cavity (131), the inner bottom surface of the first rotating part (142) corresponding to the first cavity (131), and the radial inner side of the first rotating part (142) being opposite to the radial outer side of the stator (13); and a second rotating part (143) close to the second cavity (132), the second rotating part (143) being bent to form the open cavity (11) towards the second cavity (132), and the second rotating part (143) and the first rotating part (142) forming a shoulder structure.
4. The distributed wheel drive apparatus according to claim 3, characterized by: the axial length of the first cavity (131) and the axial length of the second cavity (132) are in a ratio of 1 / 3-1 / 2; the single-side gap between the radial outer side of the stator (13) and the radial inner side of the rotor (14) is L, and 0mm 5. The distributed wheel drive apparatus according to claim 4, characterized by: The driving assembly (1) further comprises: a fixed shaft (12) connected with the stator (13) and the speed reduction assembly (2) respectively at two ends, the fixed shaft (12) being coaxial with the stator (13), the rotor (14) and the speed reduction assembly (2); a first bearing (15) arranged between the stator (13) and the first rotating part (142), the inner side and the outer side of the first bearing (15) being connected with the radial outer side of the stator (13) and the radial inner side of the first rotating part (142) respectively; and a second bearing (16) arranged between the rotor (14) and the second rotating part (143), the inner side and the outer side of the second bearing (16) being connected with the radial inner side of the rotor (14) and the radial outer side of the second rotating part (143) respectively. A reinforcing rib (16) is formed on the radially inner side of the second rotating member (143), the inner side of the reinforcing rib (16) is coaxial with the fixed shaft (12), and the inner side of the reinforcing rib (16) is formed in axial connection with the sun gear (22) of the reduction assembly (2).
6. The distributed wheel drive apparatus according to claim 5, characterized by: The reduction assembly (2) is axisymmetric, and sequentially comprises, in the power output direction, a planet carrier (21), a sun gear (22), a planet gear (23), an inner tooth ring gear (24), an output flange (25), and a cover plate (26), wherein the outer side of the sun gear (22) is formed in spline structure with the inner side of the reinforcing rib (16), and the reinforcing rib (16) can drive the sun gear (22) to rotate around the fixed shaft (12) through the spline structure.
7. The distributed wheel drive arrangement of claim 6, wherein: The housing (3) is coaxially connected with the stator (13), the inside of the housing (3) is formed in a placement cavity (31) with an open end, the drive assembly (1) is placed in the placement cavity (31), the open end of the placement cavity (31) allows the reduction assembly (2) to pass through, the housing (3) further comprises a second bearing (32) arranged at the open end of the placement cavity (31), the inner side of the second bearing (32) is connected with the outer side of the reduction assembly (2), the outer side of the second bearing (32) is connected with the inner side of the open end of the placement cavity (31), and the second bearing (32) and the reduction assembly (2) form a closed cavity in the placement cavity (31).
8. The distributed wheel drive apparatus according to claim 7, characterized by: The drive assembly (1) further comprises: A limiting protrusion (17) is formed on the outer side of the fixed shaft (12), the end face of the limiting protrusion (17) has a diameter larger than that of the fixed shaft (12), and an axial side of the limiting protrusion (17) coincides with the axial end face of the stator (13); An O-ring (18) is arranged at the coinciding surface of the limiting protrusion (17) and the stator (13), the O-ring (18) can block the cooling oil in the third cavity (141) from flowing into the coinciding part of the limiting protrusion (17) and the stator (13); and A rotor oil seal (19) is arranged in the gap between the inner side of the rotor (14) and the outer side of the fixed shaft (12), the rotor oil seal (19) can limit the cooling oil in the third cavity (141) from flowing into the gap between the rotor (14) and the fixed shaft (12). A reinforcing rib (16) is formed on the radially inner side of the second rotating member (143), the inner side of the reinforcing rib (16) is coaxial with the fixed shaft (12), and the inner side of the reinforcing rib (16) is formed in axial connection with the sun gear (22) of the reduction assembly (2). The reduction assembly (2) is axisymmetric, and sequentially comprises, in the power output direction, a planet carrier (21), a sun gear (22), a planet gear (23), an inner tooth ring gear (24), an output flange (25), and a cover plate (26), wherein the outer side of the sun gear (22) is formed in spline structure with the inner side of the reinforcing rib (16), and the reinforcing rib (16) can drive the sun gear (22) to rotate around the fixed shaft (12) through the spline structure. The housing (3) is coaxially connected with the stator (13), the inside of the housing (3) is formed in a placement cavity (31) with an open end, the drive assembly (1) is placed in the placement cavity (31), the open end of the placement cavity (31) allows the reduction assembly (2) to pass through, the housing (3) further comprises a second bearing (32) arranged at the open end of the placement cavity (31), the inner side of the second bearing (32) is connected with the outer side of the reduction assembly (2), the outer side of the second bearing (32) is connected with the inner side of the open end of the placement cavity (31), and the second bearing (32) and the reduction assembly (2) form a closed cavity in the placement cavity (31). The drive assembly (1) further comprises: A limiting protrusion (17) is formed on the outer side of the fixed shaft (12), the end face of the limiting protrusion (17) has a diameter larger than that of the fixed shaft (12), and an axial side of the limiting protrusion (17) coincides with the axial end face of the stator (13); An O-ring (18) is arranged at the coinciding surface of the limiting protrusion (17) and the stator (13), the O-ring (18) can block the cooling oil in the third cavity (141) from flowing into the coinciding part of the limiting protrusion (17) and the stator (13); and A rotor oil seal (19) is arranged in the gap between the inner side of the rotor (14) and the outer side of the fixed shaft (12), the rotor oil seal (19) can limit the cooling oil in the third cavity (141) from flowing into the gap between the rotor (14) and the fixed shaft (12).