Coaxial driving device and vehicle

Abstract

The invention provides a coaxial driving device and a vehicle, the coaxial driving device comprises a shell, a stator and a rotor, the shell comprises an end cover, and the end cover is provided with a first overflowing channel; the rotor shaft is internally provided with a cavity, the cavity penetrates through the two ends of the rotor shaft, the rotor shaft is provided with a second hole, and the second hole is communicated with the cavity and the rotor; and the penetrating shaft is arranged in the cavity of the rotor shaft in a penetrating manner, one end of the penetrating shaft extends to the end cover, a second overflowing channel is formed in the penetrating shaft, and a third hole and a fourth hole which are communicated with the second overflowing channel are formed in the penetrating shaft. After flowing out of the first hole, the cooling medium can be cached in the buffer tank and fills the buffer tank, and the pressure of the cooling medium in the buffer tank is easy to increase. Therefore, under the condition that the penetrating shaft rotates at a high speed and the first hole and the third hole are staggered, the cooling medium can flow into the third hole, and the cooling effect on the rotor is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle power systems, and in particular to a coaxial drive device and a vehicle. Background Art

[0002] The drive motor is the core component of new energy vehicles, which has the characteristics of compact structure, high power density and high efficiency. However, the motor will generate a lot of heat during operation, and the high temperature will affect the motor output performance. Therefore, how to curb the temperature rise of the motor during operation is a key factor in improving the performance of new energy vehicles.

[0003] Among the driving modes of electric vehicles, coaxial electric drive has the advantages of high mechanical efficiency and compact structure. However, since the through-shaft spans the entire drive mechanism, there are certain difficulties in the rotor oil supply method. In the prior art, two methods are usually used to achieve the cooling oil supply of the coaxial electric drive: one is to supply oil through the gap between the through-shaft and the motor shaft, but this oil supply method has high requirements for the sealing between the through-shaft and the motor shaft, and the radial dimension of the system is large, which is not conducive to the selection of parts and components, and the bearing loss will also increase; the other is to set an oil channel in the through-shaft, and introduce the cooling oil into the through-shaft at the end cover position, but the through-shaft is always in a high-speed rotation state, resulting in the oil inlet hole and the oil filling hole on the through-shaft always switching back and forth between the aligned and misaligned states, so the oil supply resistance is large and the fluctuation is large, which ultimately leads to poor cooling effect of the rotor. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defects of large fluctuation and large resistance in the through-shaft oil inlet method in the coaxial electric drive system in the prior art, thereby providing a coaxial drive device and vehicle.

[0005] In order to solve the above problems, the present invention provides a coaxial drive device, comprising: a shell, a stator and a rotor, the stator and the rotor are both arranged in the shell, the shell comprises an end cover, a first flow passage is arranged on the end cover, and a first hole connected to the first flow passage is arranged on the end cover; a rotor shaft is rotatably arranged in the shell and fixedly connected to the rotor, the rotor shaft has a cavity inside, the cavity passes through both ends of the rotor shaft, a second hole is arranged on the rotor shaft, and the second hole is connected to the cavity and the rotor; a through shaft is penetrated in the cavity of the rotor shaft, and one end of the through shaft extends to the end cover, a second flow passage is arranged in the through shaft, and a third hole and a fourth hole connected to the second flow passage are arranged on the through shaft, the third hole is connected to the first hole, and the fourth hole is connected to the cavity, wherein a buffer groove is arranged on the surface of the end cover and / or the surface of the through shaft at the matching position of the end cover and the through shaft, and the first hole and the third hole are both connected to the buffer groove.

[0006] Optionally, the buffer groove is annular and extends along the circumferential direction.

[0007] Optionally, a rotating shaft hole is provided on the end cover, one end of the penetrating shaft is inserted into the rotating shaft hole, and the buffer groove is provided on the hole wall of the rotating shaft hole.

[0008] Optionally, two sets of sealing structures are provided between the end cover and the through shaft, and the two sets of sealing structures are respectively located on both sides of the buffer groove along the axial direction.

[0009] Optionally, there are a plurality of fourth holes, and at least some of the fourth holes are staggered along the axial direction of the through-shaft; and / or at least some of the fourth holes are staggered along the circumferential direction of the through-shaft.

[0010] Optionally, a limiting groove is provided on the inner wall of the cavity, the second hole is provided at the bottom of the limiting groove, and the fourth hole is located within the range of the limiting groove in the axial direction along the through-axis.

[0011] Optionally, the limiting groove is annular and extends along the circumference of the rotor shaft.

[0012] Optionally, the rotor comprises a cooling channel, the second holes comprise a first hole group, and the first hole group is in communication with the cooling channel.

[0013] Optionally, the second holes further include a second hole group, the second hole group is located outside the rotor, and the first hole group and the second hole group are staggered along the axial direction of the rotor shaft.

[0014] The present invention also provides a vehicle, comprising the above-mentioned coaxial drive device.

[0015] The present invention has the following advantages:

[0016] By using the technical solution of the present invention, the cooling medium is introduced from the first flow passage of the end cover, and enters the through-shaft through the first hole and the third hole, and then the cooling medium is introduced into the rotor through the second flow passage, the third hole and the first hole, thereby cooling the rotor. During the operation of the coaxial drive device, the third hole rotates at a high speed relative to the first hole, and switches back and forth between the aligned and misaligned states. After the cooling medium flows out of the first hole, it can be buffered in the buffer tank and fill the buffer tank first, and the cooling medium can easily increase the pressure in the buffer tank. Therefore, when the through-shaft rotates at a high speed and the first hole and the third hole are misaligned, the cooling medium can also flow into the third hole, and it can be ensured that the cooling medium discharged from the second hole has a higher pressure and a smaller pressure fluctuation, thereby ensuring the cooling effect on the rotor. Therefore, the technical solution of the present invention solves the defects of large fluctuations and large resistance in the through-shaft oil inlet method in the coaxial electric drive system in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A schematic structural diagram of the coaxial drive device of the present invention is shown;

[0019] Figure 2 Shows Figure 1 A schematic cross-sectional view of the coaxial drive device;

[0020] Figure 3 Shows Figure 2 A schematic diagram of the structure at the middle end cover position;

[0021] Figure 4 Shows Figure 2 A schematic diagram of the structure at the second hole in the middle;

[0022] Figure 5 Shows Figure 1 A schematic diagram of the structure of the end cover of the coaxial drive device;

[0023] Figure 6 Shows Figure 5 A schematic cross-sectional view of the middle end cover;

[0024] Figure 7 Shows Figure 1 A schematic diagram of the structure of the rotor shaft of the coaxial drive device;

[0025] Figure 8 Shows Figure 7 A schematic cross-sectional view of the rotor shaft;

[0026] Fig. 9 Shows Figure 1 A schematic diagram of the structure of the through-shaft of the coaxial drive device;

[0027] Fig.10 Shows Fig. 9 Schematic cross-sectional view of the through shaft.

[0028] Description of reference numerals:

[0029] 10. stator; 20. rotor; 30. end cover; 31. first flow channel; 32. first hole; 33. shaft hole; 40. rotor shaft; 41. cavity; 411. limit groove; 42. second hole; 421. first hole group; 422. second hole group; 50. through shaft; 51. second flow channel; 52. third hole; 53. fourth hole; 60. buffer groove; 70. sealing structure. DETAILED DESCRIPTION

[0030] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0032] In the description of the present invention, 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 it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0034] like Figures 1 to 10As shown, an embodiment of the coaxial drive device according to the present application includes a housing, a stator 10, a rotor 20, a rotor shaft 40 and a through shaft 50. The stator 10 and the rotor 20 are both arranged in the housing, and the housing includes an end cover 30, a first flow passage 31 is arranged on the end cover 30, and a first hole 32 communicating with the first flow passage 31 is arranged on the end cover 30. The rotor shaft 40 is rotatably arranged in the housing and fixedly connected to the rotor 20. The rotor shaft 40 has a cavity 41 inside, and the cavity 41 passes through both ends of the rotor shaft 40. The rotor shaft 40 is provided with a second hole 42, and the second hole 42 is communicated with the cavity 41 and the rotor 20. The through shaft 50 is penetrated in the cavity 41 of the rotor shaft 40, and one end of the through shaft 50 extends to the end cover 30. A second flow passage 51 is disposed in the through shaft 50 . A third hole 52 and a fourth hole 53 communicating with the second flow passage 51 are disposed on the through shaft 50 . The third hole 52 is communicated with the first hole 32 , and the fourth hole 53 is communicated with the cavity 41 .

[0035] Furthermore, at the mating position between the end cover 30 and the through shaft 50 , a buffer groove 60 is provided on the surface of the end cover 30 and / or the surface of the through shaft 50 , and both the first hole 32 and the third hole 52 are connected to the buffer groove 60 .

[0036] By using the technical solution of this embodiment, the cooling medium is introduced from the first flow passage 31 of the end cover 30, and enters the through shaft 50 through the first hole 32 and the third hole 52, and then the cooling medium is introduced into the rotor 20 through the second flow passage 51, the third hole 52 and the first hole 32, so as to cool the rotor 20. During the operation of the coaxial drive device, the third hole 52 rotates at a high speed relative to the first hole 32, and switches back and forth between the aligned and misaligned states. After the cooling medium flows out from the first hole 32, it can be buffered in the buffer groove 60 and fill the buffer groove 60, and the cooling medium can easily increase the pressure in the buffer groove 60. Therefore, when the through shaft 50 rotates at a high speed and the first hole 32 and the third hole 52 are misaligned, the cooling medium can also flow into the third hole 52, and it can be ensured that the cooling medium discharged from the second hole 42 has a higher pressure and a smaller pressure fluctuation, thereby ensuring the cooling effect on the rotor 20. Therefore, the technical solution of this embodiment solves the defects of large fluctuations and large resistance in the through shaft oil inlet mode in the coaxial electric drive system in the prior art.

[0037] It should be noted that the cooling medium in this embodiment is cooling lubricating oil. Of course, the cooling medium may also be other liquids, gases, etc.

[0038] The coaxial drive device comprises a housing, which is also the housing of the motor. The housing comprises an end cover 30, which is arranged at the axial end position of the housing. Figure 5 and Figure 6It can be seen that the end cover 30 is roughly an umbrella-shaped structure. A first flow passage 31 is provided in the end cover 30. Figure 5 It can be seen that the first flow channel 31 forms an inlet on the outer surface of the end cover 30 , and the cooling medium can enter the first flow channel 31 through the inlet.

[0039] from Figure 6 It can be seen that a first hole 32 is provided at the inner side of the end cover 30 , and the first hole 32 is communicated with the first flow channel 31 , so the cooling medium can be discharged from the end cover 30 through the first hole 32 .

[0040] Furthermore, the housing is provided with a stator 10 and a rotor 20. When powered, the rotor 20 can rotate around its axis to provide driving force. At the same time, a large amount of heat is generated during the high-speed rotation of the rotor 20, so the rotor 20 needs to be cooled to ensure the performance of the motor.

[0041] from Figure 2 It can be seen that the rotor shaft 40 is arranged in the housing, the inner hole of the rotor 20 is sleeved outside the rotor shaft 40, and the rotor shaft 40 is fixedly arranged with the inner hole of the rotor 20. Therefore, when the rotor 20 rotates at a high speed, it can drive the rotor shaft 40 to rotate synchronously.

[0042] from Figure 7 and Figure 8 It can be seen that the rotor shaft 40 has an inner cavity, and the inner cavity passes through both ends of the rotor shaft 40, so the rotor shaft 40 is a hollow shaft structure with both ends open. The rotor shaft 40 is also provided with a second hole 42, and the second hole 42 passes through the inside and outside of the rotor shaft 40. The inside of the second hole 42 is connected to the cavity 41, and the outside is connected to the rotor 20.

[0043] The “outer side of the second hole 42 is connected to the rotor 20” means that the cooling medium discharged from the second hole 42 can flow to the inside or outer surface of the rotor 20, thereby cooling the rotor 20. This includes that the second hole 42 is connected to the cooling channel of the rotor 20, or the second hole 42 is connected to the outer space of the rotor 20.

[0044] from Figure 2 It can be seen that the through shaft 50 is inserted into the cavity 41 of the rotor shaft 40, and the two are coaxially arranged. The two ends of the through shaft 50 pass through the two ends of the rotor shaft 40, and Figure 2 In the direction shown, the right end of the through-shaft 50 passes through the end cap 30 .

[0045] During the actual operation of the coaxial drive device, the rotor 20 drives the rotor shaft 40 to rotate, and then Figure 2In the left position shown, the rotor shaft 40 and the through shaft 50 are connected by a speed change mechanism. That is, the rotation of the rotor shaft 40 (or the rotation of the rotor 20) is transmitted to the through shaft 50 after the speed change, that is, the rotor shaft 40 and the through shaft 50 rotate asynchronously. The rotation of the through shaft 50 is output to the wheels, thereby realizing the driving of the vehicle.

[0046] Further, from Fig. 9 and Fig.10 It can be seen that a second flow passage 51 is provided in the through-shaft 50. The second flow passage 51 is specifically provided at the central axis position of the through-shaft 50 and extends along the axial direction of the through-shaft 50. Figure 2 The through shaft 50 is also provided with a third hole 52 and a fourth hole 53, wherein the third hole 52 and the fourth hole 53 both extend along the radial direction of the through shaft 50, and both communicate with the second flow passage 51 and the outer side of the through shaft 50. The third hole 52 and the fourth hole 53 are staggered along the circumferential direction of the through shaft 50.

[0047] from Figure 6 It can be seen that a buffer groove 60 is provided on the inner side of the end cover 30 , and the first hole 32 is located in the buffer groove 60 , that is, the first hole 32 is connected to the buffer groove 60 .

[0048] When the components are assembled, the relationship between Figure 3 and Figure 4 As shown, the third hole 52 is communicated with the buffer groove 60 , and the fourth hole 53 is communicated with the cavity 41 .

[0049] Based on the above structure, the flow mode of the cooling medium in the coaxial drive device in this embodiment is described below:

[0050] 1. The cooling medium is introduced into the end cover 30 from the first flow passage 31, and then discharged from the first hole 32 and enters the buffer tank 60;

[0051] 2. The cooling medium enters the second flow channel 51 penetrating the shaft 50 through the third hole 52 in the buffer groove 60;

[0052] 3. The cooling medium enters the cavity 41 through the fourth hole 53;

[0053] 4. The cooling medium is discharged to the rotor 20 through the second hole 42 , thereby cooling the rotor 20 .

[0054] In the above structure, those skilled in the art can understand that during the rotation of the through shaft 50, the third hole 52 rotates at a high speed relative to the first hole 32, and the two are switched back and forth between the aligned and misaligned states, which will bring about the following two problems:

[0055] 1. During the rotation of the through-shaft 50, the cooling medium can smoothly enter the through-shaft 50 from the end cover 30 only when the third hole 52 and the first hole 32 are completely aligned. In other states (the third hole 52 and the first hole 32 are partially aligned or completely misaligned), the cooling medium has a large flow resistance, so the flow rate of the cooling medium discharged at the second hole 42 fluctuates greatly.

[0056] 2. Since the apertures of the third hole 52 and the first hole 32 are relatively small, the two can be aligned only for a very short time during the rotation of the through-shaft 50. At other times, the cooling medium has a large flow resistance. Therefore, from an overall perspective, the cooling medium discharged from the second hole 42 has a smaller pressure, that is, a smaller flow rate, and the cooling effect on the rotor 20 is weaker.

[0057] In order to solve these two problems, a buffer groove 60 is added in this embodiment. That is, after the cooling medium is discharged from the first hole 32, it can be filled in the buffer groove 60 first. After the buffer groove 60 is filled with the cooling medium, the pressure of the cooling medium in the buffer groove 60 increases, and the fluidity is stronger. Therefore, no matter whether the third hole 52 and the first hole 32 are completely aligned, partially aligned or misaligned, the cooling medium can flow smoothly into the third hole 52. Therefore, the flow rate of the cooling medium discharged from the second hole 42 is stable and large, and the cooling effect on the rotor 20 is better.

[0058] from Figure 3 From the contents shown, those skilled in the art can understand that, in the two opposite surfaces where the end cover 30 and the through shaft 50 cooperate, the buffer groove 60 can be provided on the surface of the end cover 30, or on the surface of the through shaft 50, or the buffer groove 60 can be provided on the surfaces of both the end cover 30 and the through shaft 50.

[0059] In fact, as long as both the first hole 32 and the third hole 52 are connected to the buffer tank 60 , the cooling medium can be stored in the buffer tank 60 before entering the third hole 52 .

[0060] like Figure 3 and Figure 6 As shown, in the technical solution of this embodiment, the buffer groove 60 is annular, and the buffer groove 60 extends along the circumferential direction.

[0061] Specifically, the annular buffer groove 60 ensures that the third hole 52 is within the range of the buffer groove 60 no matter to which angle the through shaft 50 is rotated, thereby ensuring that the cooling medium can smoothly enter the third hole 52 after being pressurized in the buffer groove 60 .

[0062] from Fig. 9It can also be seen that the third holes 52 are arranged in plurality, and the plurality of third holes 52 are evenly distributed along the circumferential direction. Such arrangement enables the cooling medium to enter the through-shaft 50 through a shorter path after being discharged from the first hole 32, thereby reducing the flow resistance of the cooling medium and increasing the flow rate of the cooling medium discharged from the second hole 42.

[0063] Furthermore, the plurality of third holes 52 are located at the same axial position, and such a configuration ensures that during the rotation of the through-shaft 50 , the plurality of third holes 52 can all be within the range of the buffer groove 60 , and the buffer groove 60 does not need to have a larger width.

[0064] Optionally, the number of the third holes 52 may be three, four, five, or the like.

[0065] In addition, the plurality of third holes 52 are evenly distributed along the circumferential direction to ensure that the through-shaft 50 has a stable center of mass, thereby ensuring that the through-shaft 50 does not vibrate significantly during high-speed rotation.

[0066] from Figure 3 It can also be seen that the cross-sectional shape of the buffer groove 60 includes a bottom edge and two side edges, one of which is a straight edge and the other is a beveled edge. Further, the side of the cross-sectional shape of the buffer groove 60 facing the rotor 20 is a beveled edge, and the beveled edge is inclined toward the rotor 20.

[0067] like Figure 3 , Figure 5 and Figure 6 As shown, in the technical solution of this embodiment, a shaft hole 33 is provided on the end cover 30 , one end of the through shaft 50 is passed through the shaft hole 33 , and the buffer groove 60 is provided on the hole wall of the shaft hole 33 .

[0068] Specifically, the through shaft 50 passes through the shaft hole 33, thereby passing through the end cover 30. Figure 6 It can be seen that the shaft hole 33 has a plurality of stepped surfaces, and the buffer groove 60 is arranged on the surface of the shaft hole 33 closest to the through-shaft 50. Figure 6 In the embodiment of the present invention, the cooling medium 50 is disposed on the wall on the left side of the shaft hole 33. In this way, the gap between the through shaft 50 and the shaft hole 33 and the buffer groove 60 form a small chamber. When the cooling medium flows into the chamber, the chamber can be quickly filled up, and the pressure of the cooling medium is increased, thereby increasing the pressure of the cooling medium discharged from the second hole 42.

[0069] like Figure 3 and Figure 6 As shown, in the technical solution of this embodiment, two sets of sealing structures 70 are arranged between the end cover 30 and the through shaft 50 , and the two sets of sealing structures 70 are respectively located on both sides of the buffer groove 60 along the axial direction.

[0070] Specifically, the above-mentioned closed chamber is formed between the two sets of sealing structures 70, the outer surface of the through-shaft 50, the inner surface of the shaft hole 33, and the buffer groove 60. Further, the sealing structure 70 includes a sealing ring, and a mounting ring groove is provided on the outer surface of the through-shaft 50, and the sealing ring is arranged in the mounting ring groove. When the through-shaft 50 is installed in the shaft hole 33, the sealing ring is compressed and deformed.

[0071] Furthermore, there are two mounting ring grooves, which are respectively located on two sides of the third hole 52 in the axial direction, and are used to install two sealing rings respectively.

[0072] like Fig. 9 As shown, in the technical solution of this embodiment, there are multiple fourth holes 53, and at least some of the fourth holes 53 are staggered along the axial direction of the through-shaft 50; and / or, at least some of the fourth holes 53 are staggered along the circumferential direction of the through-shaft 50.

[0073] Since the torque transmitted by the through-shaft 50 is relatively large, when the fourth hole 53 is formed on the through-shaft 50 , it is necessary to ensure that the strength of the through-shaft 50 meets the requirements.

[0074] Specifically, in this embodiment, a plurality of fourth holes 53 are provided, thereby increasing the number of channels for the cooling medium to flow out of the through-shaft 50. In addition, in this embodiment, the plurality of fourth holes 53 are arranged to be staggered in the axial direction or the circumferential direction, so as to prevent too many fourth holes 53 from being opened at a certain position of the through-shaft 50, resulting in a situation where the strength of the position is relatively weak.

[0075] from Fig. 9 and Fig.10 It can be seen that the plurality of fourth holes 53 in the embodiment are divided into two groups, and the two groups of fourth holes 53 are staggered in the axial direction of the through-shaft 50. Moreover, each group of fourth holes 53 includes a plurality of fourth holes 53, and the plurality of fourth holes 53 in the same group are arranged at intervals along the circumferential direction of the through-shaft 50, and the fourth holes 53 in different groups are staggered in the circumferential direction of the through-shaft 50. In this way, it can be ensured that there is no area of ​​the through-shaft 50 where a large number of fourth holes 53 are arranged.

[0076] In some embodiments not shown, the arrangement of the plurality of fourth holes 53 can be determined by those skilled in the art according to actual needs, as long as there is no region of the through-shaft 50 where a large number of fourth holes 53 are arranged and the center of mass of the through-shaft 50 is stable.

[0077] like Figure 4 and Figure 8 As shown, in the technical solution of this embodiment, a limiting groove 411 is provided on the inner wall of the cavity 41, and the second hole 42 is provided at the bottom of the limiting groove 411. In the axial direction along the through shaft 50, the fourth hole 53 is located within the range of the limiting groove 411.

[0078] Specifically, during the rotation of the through shaft 50, the cooling medium is thrown from the fourth hole 53 to the inner wall of the cavity 41. The function of the limiting groove 411 is to limit the cooling medium within the range surrounded by the limiting groove 411, that is, to limit the cooling medium to a position near the second hole 42. In this way, the cooling medium is prevented from adhering to the wall far from the second hole 42, thereby reducing the loss of the cooling medium and improving the cooling efficiency of the multi-rotor 20.

[0079] like Figure 4 and Figure 8 As shown, the limiting groove 411 is annular and extends along the circumference of the rotor shaft 40. In this way, the limiting groove 411 can limit the cooling medium to a position near the second hole 42 in the entire circumference.

[0080] like Figure 4 and Figure 8 As shown, in the technical solution of this embodiment, the rotor 20 includes a cooling channel, the second hole 42 includes a first hole group 421, and the first hole group 421 is connected to the cooling channel.

[0081] Specifically, the cooling medium ejected from the first hole group 421 can enter the cooling channel in the rotor 20 , thereby cooling the interior of the rotor 20 .

[0082] like Figure 4 and Figure 8 As shown, in the technical solution of this embodiment, the second hole 42 also includes a second hole group 422, the second hole group 422 is located outside the rotor 20, and the first hole group 421 and the second hole group 422 are staggered along the axial direction of the rotor shaft 40.

[0083] Specifically, the cooling medium ejected from the second hole group 422 can be ejected onto the outer surface of the rotor 20 , that is, the windings on the rotor 20 can be cooled.

[0084] Optionally, the first hole group 421 includes a plurality of second holes 42 , and the plurality of second holes 42 of the first hole group 421 are arranged at intervals along the circumferential direction of the rotor shaft 40 .

[0085] Optionally, the second hole group 422 includes a plurality of second holes 42 , and the plurality of second holes 42 of the second hole group 422 are spaced apart along the circumferential direction of the rotor shaft 40 .

[0086] The present application also provides a vehicle. According to an embodiment of the vehicle of the present application, the vehicle includes the above-mentioned coaxial drive device.

[0087] Optionally, the vehicle is a new energy electric vehicle.

[0088] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A coaxial drive device, characterized in that: include: A housing, a stator (10) and a rotor (20), wherein the stator (10) and the rotor (20) are both arranged in the housing, the housing comprises an end cover (30), a first flow passage (31) is arranged on the end cover (30), and a first hole (32) communicating with the first flow passage (31) is arranged on the end cover (30); A rotor shaft (40) is rotatably disposed in the housing and fixedly connected to the rotor (20); the rotor shaft (40) has a cavity (41) inside, the cavity (41) passes through both ends of the rotor shaft (40); a second hole (42) is provided on the rotor shaft (40), and the second hole (42) is in communication with the cavity (41) and the rotor (20); A through shaft (50) is inserted into the cavity (41) of the rotor shaft (40), and one end of the through shaft (50) extends to the end cover (30). A second flow passage (51) is provided in the through shaft (50). A third hole (52) and a fourth hole (53) communicating with the second flow passage (51) are provided on the through shaft (50). The third hole (52) is communicated with the first hole (32), and the fourth hole (53) is communicated with the cavity (41). Wherein, at the fitting point between the end cover (30) and the through shaft (50), a buffer groove (60) is provided on the surface of the end cover (30) / or the surface of the through shaft (50), and the first hole (32) and the third hole (52) are both connected to the buffer groove (60).

2. The coaxial drive device according to claim 1, characterized in that: The buffer groove (60) is annular, and the buffer groove (60) extends along the circumferential direction.

3. The coaxial drive device according to claim 1 or 2, characterized in that: The end cover (30) is provided with a rotating shaft hole (33), one end of the through-shaft (50) is inserted into the rotating shaft hole (33), and the buffer groove (60) is provided on the hole wall of the rotating shaft hole (33).

4. The coaxial drive device according to claim 3, characterized in that: Two groups of sealing structures (70) are arranged between the end cover (30) and the through shaft (50), and the two groups of sealing structures (70) are respectively located on both sides of the buffer groove (60) along the axial direction.

5. The coaxial drive device according to claim 1 or 2, characterized in that: There are a plurality of fourth holes (53), and at least some of the fourth holes (53) are staggered along the axial direction of the through-shaft (50); and / or at least some of the fourth holes (53) are staggered along the circumferential direction of the through-shaft (50).

6. The coaxial drive device according to claim 1 or 2, characterized in that: The inner wall of the cavity (41) is provided with a limiting groove (411), the second hole (42) is provided at the bottom of the limiting groove (411), and in the axial direction along the through shaft (50), the fourth hole (53) is located within the range of the limiting groove (411).

7. The coaxial drive device according to claim 6, characterized in that: The limiting groove (411) is annular in shape, and extends along the circumference of the rotor shaft (40).

8. The coaxial drive device according to claim 1 or 2, characterized in that: The rotor (20) comprises a cooling channel, and the second holes (42) comprise a first hole group (421), wherein the first hole group (421) is in communication with the cooling channel.

9. The coaxial drive device according to claim 8, characterized in that: The second hole (42) further comprises a second hole group (422), the second hole group (422) being located outside the rotor (20), and the first hole group (421) and the second hole group (422) being staggered along the axial direction of the rotor shaft (40).

10. A vehicle, characterized in that: A coaxial drive device comprising any one of claims 1 to 9.

Images