Electric machines, powertrains and electric vehicles

Abstract

The application provides a motor, a power assembly and an electric vehicle. A motor shell of the motor is used for fixing a stator of the motor and accommodating a rotor of the motor. A circumferential wall of the motor shell comprises a plurality of bolt bosses and at least one protrusion. The plurality of bolt bosses are distributed on a side of the circumferential wall of the motor shell away from the stator along a circumferential direction of the motor. The plurality of bolt bosses and the at least one protrusion are protruded away from the stator along a radial direction of the motor. The plurality of bolt bosses are used for fixing an end cover of the motor. The at least one protrusion is arranged adjacent to the plurality of bolt bosses along an axial direction of the motor. Each protrusion is connected to at least two bolt bosses away from the end cover on a side of the end cover, so that the protrusion can receive and disperse stress of the end away from the end cover of the bolt boss, thereby improving the problem of stress concentration and large stress at the root of the bolt boss, and facilitating improvement of the efficiency of the stator interference simulation iteration.

Description

Technical Field

[0001] This application relates to the field of electric vehicle technology, and particularly to an electric motor, powertrain, and electric vehicle. Background Technology

[0002] The powertrain includes the motor. The motor housing and stator are fitted with an interference fit. The bolt bosses on the motor housing, which are used to fit with the end cover, have thick and uneven walls, causing stress concentration at these bosses. This can easily lead to stress concentration and cracking of the motor housing, and can also cause hot spots and localized shrinkage cavities during the die-casting process, affecting the product's yield, strength, durability, and reliability. To reduce the stress at the root of the bolt bosses during the stator interference fit process, additional material and large fillet radius are usually added to the root of the bolt bosses. However, this method suffers from low simulation iteration efficiency for stator interference fits. Utility Model Content

[0003] This application provides an electric motor, powertrain, and electric vehicle to relieve stress at the root of the bolt bosses on the mating surface of the motor housing and end cover, thereby improving the efficiency of stator interference simulation iteration.

[0004] In a first aspect, this application provides an electric motor. The motor housing is used to fix the stator of the motor and to house the rotor. The circumferential wall of the motor housing includes a plurality of bolt bosses and at least one protrusion. The plurality of bolt bosses are spaced apart around the circumference of the motor on the side of the circumferential wall of the motor housing opposite to the stator. The plurality of bolt bosses and at least one protrusion are radially opposite to the stator protrusion of the motor. The plurality of bolt bosses are used to fix an end cover of the motor. At least one protrusion is arranged adjacent to the plurality of bolt bosses along the axial direction of the motor, and the side of each protrusion facing the end cover is connected to the end of at least two bolt bosses opposite to the end cover.

[0005] In this embodiment, multiple bolt bosses are distributed at intervals around the circumference of the motor housing on the side of the circumferential wall away from the stator, making the fixation between the multiple bolt bosses of the motor housing and the end cover more stable.

[0006] In this embodiment, at least one protrusion and multiple bolt bosses are arranged adjacent to each other along the axial direction of the motor, which facilitates the connection of at least one protrusion and multiple bolt bosses along the axial direction of the motor.

[0007] In this embodiment, since the motor housing and stator are fixed by a thermal interference fit, the bolt bosses used to fix the motor housing to the end cover have thick and uneven walls, which easily leads to stress concentration and high stress, affecting the quality of the motor housing product. By connecting the side of each protrusion facing the end cover to the end of at least two bolt bosses facing away from the end cover, the stress at the end of the bolt bosses facing away from the end cover can be dispersed by the protrusions, thereby improving the problem of stress concentration and high stress at the root of the bolt bosses. The reduced stator interference stress also helps to improve the iteration efficiency of stator interference simulation. Connecting the bolt bosses to the end facing away from the end cover with the protrusions also helps to enhance the flow of molten aluminum during the die casting process, reduce the probability of hot spots in the die casting, reduce the probability of gas shrinkage cavities in the area where the end of the bolt boss facing away from the end cover intersects with the motor housing, and improve the strength of the motor housing.

[0008] In this application, multiple bolt bosses are provided on the circumferential wall of the motor housing near the side used for fixing to the end cover of the motor. Each boss connects to at least two bolt bosses at the end away from the end cover. This disperses the stress at the end of the bolt bosses away from the end cover, thus improving the problem of stress concentration and high stress at the root of the bolt bosses. The stator interference stress is significantly reduced, effectively decreasing the number of iterations required for stator interference simulation. Connecting the bolt bosses at the end away from the end cover also enhances the flow of molten aluminum, reducing the probability of hot spots in the motor housing. This further reduces the probability of air pockets forming at the intersection of the bolt bosses at the end away from the end cover and the motor housing, improving the strength of the motor housing.

[0009] In one embodiment, at least two bolt bosses are aligned circumferentially with respect to one end of the end cover along the axial direction of the motor. The surface of each boss facing the end cover along the axial direction of the motor is planar and perpendicular to the axial direction of the motor.

[0010] In this embodiment, at least two bolt bosses are aligned along the circumference of the motor from one end of the end cover along the axial direction of the motor. This facilitates the connection between the ends of the bolt bosses away from the end cover and the protrusions, and also allows the protrusions to extend along the circumference of the motor. This makes it easier for the protrusions to receive the stress from the ends of the bolt bosses away from the end cover and then disperse it along the circumference of the motor, which is more conducive to improving the stress concentration problem and thus increasing the number of stator interference simulation iterations.

[0011] In this embodiment, the surface of each protrusion facing the end cover along the motor's axial direction is flat and perpendicular to the motor's axial direction, facilitating connection between the protrusion and the end of the bolt boss away from the end cover. This also facilitates enhanced aluminum melt flow during die casting of the motor housing, reducing the probability of hot spots in the motor housing, thereby lowering the probability of shrinkage cavities forming in the area where the end of the bolt boss away from the end cover intersects with the motor housing, and improving the strength of the motor housing. Furthermore, it facilitates direct draft forming of the connection between the protrusion and the bolt boss.

[0012] In one embodiment, each protrusion along the radial direction of the motor is opposite to one end of the stator and opposite to one side of at least two bolt bosses connected to the protrusion.

[0013] In this embodiment of the application, each protrusion along the radial direction of the motor has one end away from the stator and at least two bolt bosses connected to it protruding to the side away from the stator. This allows the protrusion along the radial direction of the motor to envelop the side of the at least two bolt bosses connected to it away from the stator, which facilitates the protrusion to receive and disperse the stress at the end of the bolt bosses away from the end cap. This can effectively reduce the number of iterations in the interference simulation of the product stator.

[0014] In one embodiment, along the axial direction of the motor, the end of each protrusion facing away from the stator is flush with the side of at least two bolt bosses connected to the protrusion facing away from the stator. This ensures that the protrusion does not occupy additional radial space beyond the bolt bosses of the motor housing along the radial direction of the motor, resulting in a smaller radial volume of the motor housing, which is beneficial for reducing the radial volume of the motor.

[0015] In one embodiment, along the circumference of the motor, the length of each protrusion is equal to the sum of the lengths of the two farthest bolt protrusions among the at least two bolt protrusions connected to it and the distance between them.

[0016] In the embodiments of this application, along the circumference of the motor, the length of each protrusion is equal to the sum of the lengths of the two farthest bolt protrusions among the at least two bolt protrusions connected to it and the distance between them, so that the protrusions do not occupy too much space of the motor housing along the circumference of the motor, which is beneficial to making the volume of the motor housing smaller.

[0017] In one embodiment, along the circumference of the motor, the length of each protrusion is greater than the sum of the lengths of the two farthest bolt protrusions among the at least two bolt protrusions connected to it and the distance between them.

[0018] In this embodiment, along the circumference of the motor, the length of each protrusion is greater than the sum of the lengths of the two farthest bolt protrusions among the at least two bolt protrusions connected to it and the distance between them. The larger length of each protrusion makes the protrusion longer along the circumference of the motor, which is more conducive to dispersing the stress of the bolt protrusion away from the end cover along the circumference of the motor, thereby increasing the number of stator interference simulation iterations.

[0019] In one embodiment, at least one protrusion is arranged adjacent to a first portion of the motor housing along the circumferential direction of the motor, the first portion is radially away from the stator protrusion, and at least one protrusion is connected to the first portion at one end along the circumferential direction of the motor near the first portion.

[0020] In this embodiment, the first part of the motor housing is radially away from the stator protrusion, and at least one protrusion is connected to the first part at one end near the first part along the circumference of the motor. This allows the two ends of the protrusion along the circumference of the motor to be independent of the bolt boss, so that the stress at the end of the bolt boss away from the end cover received by the protrusion can be dispersed through the first part of the motor housing. This results in a better effect on the release of stator interference stress and can effectively reduce the number of iterations of stator interference simulation for the product.

[0021] In one embodiment, the first portion of the motor housing can be used to form an internal flow channel within the motor housing. In another embodiment, the first portion of the motor housing can be used to form the wall of a receiving groove, which can be used to accommodate the motor or other structural components in the powertrain, such as three-phase connectors. In yet another embodiment, the first portion of the motor housing can also be used to form a retaining wall or a fixing boss for mounting and fixing the motor.

[0022] In one embodiment, each protrusion includes two opposite ends along the circumference of the motor, at least one of the ends being spaced apart from at least two bolt bosses connected to the protrusion, and one of the ends being adjacent to a bolt boss of the at least two bolt bosses spaced apart along the circumference of the motor, and the radial length of the protrusion along the motor gradually decreases from the portion of it connected to a bolt boss towards one end along the circumference of the motor.

[0023] In this embodiment, one of the two ends is arranged adjacent to one of the bolt bosses of at least two bolt bosses along the circumference of the motor. The length of the protrusion along the radial direction of the motor gradually decreases from the part connected to a bolt boss towards one end along the circumference of the motor, so that the length of the protrusion at one end along the radial direction of the motor is smaller. This makes it easier for the protrusion to disperse the stress received from the end of the bolt boss away from the end cover to the circumferential wall of the motor housing for release. This results in a better stator interference stress release effect and can effectively reduce the number of iterations of stator interference simulation for the product.

[0024] In one embodiment, the length of each protrusion along the radial direction of the motor is greater than the length of the protrusion along the axial direction of the motor.

[0025] In this embodiment, the radial length of each protrusion along the motor is greater than the axial length of the protrusion along the motor, while the axial length of the protrusion is smaller. This results in a smaller axial space occupied by the protrusion in the motor housing, while still dispersing the stress at the end of the bolt boss away from the end cover. The smaller axial length of the protrusion also helps to save materials and reduce weight.

[0026] In one embodiment, the outer diameter of each bolt boss connected to the protrusion gradually decreases along the axial direction of the motor from its two opposite ends toward the middle, and the minimum cross-sectional area of ​​each bolt boss connected to the protrusion is greater than the cross-sectional area of ​​the fixing hole in each bolt boss.

[0027] In this embodiment, the outer diameter of each bolt boss connected to the protrusion gradually decreases along the axial direction of the motor from its two opposite ends toward the middle. This avoids excessive thickness at the root of the bolt boss and makes it easier for each bolt boss to distribute the stress it experiences to the protrusion, thus facilitating stress release. It also helps save on motor housing material and reduce weight.

[0028] In the embodiments of this application, the minimum cross-sectional area of ​​each bolt boss connected to the protrusion is greater than the cross-sectional area of ​​the fixing hole in each bolt boss, so that the bolt boss can effectively disperse stress without affecting the fixing strength between the bolt boss and the end cover, which is beneficial to improving motor performance.

[0029] In one embodiment, the area of ​​each bolt boss connected to the protrusion at one end away from the end cap and connected to the protrusion is greater than the cross-sectional area of ​​the bolt boss other than at one end along the direction perpendicular to the axial direction of the motor.

[0030] In the embodiments of this application, the area of ​​each bolt boss connected to the protrusion at the end away from the end cover is relatively large, which can better transfer the stress of the bolt boss to the protrusion, and the stress is more evenly distributed, which is more conducive to improving the stress concentration problem, thereby reducing the number of iterations of the stator interference simulation of the product.

[0031] In one embodiment, a groove is formed by two adjacent bolt bosses connected to the protrusion, a portion of the protrusion between the two adjacent bolt bosses, and the outer surface of the circumferential wall of the motor housing. The radial bottom of the groove is recessed towards the stator along the radial direction of the motor. The groove width between two adjacent bolt bosses along the circumferential direction of the motor is greater than the length of the portion of the protrusion between the two adjacent bolt bosses.

[0032] In the embodiments of this application, a groove is formed by the outer surface of the outer surface of the circumferential wall of the motor housing and the outer surface of the two adjacent bolt bosses connected to the protrusion, as well as the portion of the protrusion and the portion of the motor housing between the two adjacent bolt bosses. The radial bottom of the groove is recessed towards the stator along the radial direction of the motor, which helps to reduce the thickness of the circumferential wall of the portion of the motor housing between the two adjacent bolt bosses and saves materials.

[0033] In this embodiment, the groove width between two adjacent bolt bosses along the circumference of the motor is greater than the length of the protrusion between the two adjacent bolt bosses. The larger groove width facilitates the dispersion of stress on the two adjacent bolt bosses, resulting in better stator interference stress release and effectively reducing the number of iterations for stator interference simulation.

[0034] In one embodiment, along the axial direction of the motor, a portion of the motor housing distributed on the side of the protrusion facing the end cover shares a draft die, and another portion of the motor housing distributed on the other side of the protrusion away from the end cover shares a different draft die. The drafting directions of the one draft die and the other draft die intersect the axial direction of the motor.

[0035] In this embodiment, along the motor's axial direction, a portion of the motor housing located on the side of the protrusion facing the end cover shares a single draft die, while another portion of the motor housing located on the side of the protrusion facing away from the end cover shares a separate draft die. The protrusion solves the mold parting problem for the motor housing, thereby improving the product's manufacturability. In one embodiment, the draft direction of one draft die is the same as that of the other draft die. In another embodiment, the draft direction of one draft die intersects with that of the other draft die.

[0036] In one embodiment, radial protrusions of the motor are arranged opposite to the stator core of the stator, and the protrusions are arranged axially between the two opposite ends of the stator core along the motor's axial direction.

[0037] In this embodiment, the radial protrusions of the motor are arranged opposite to the stator core of the stator, so that the protrusions can better receive the stress generated by the stator core on the motor housing, which is more conducive to releasing the stator interference stress by using the protrusions and can effectively improve the simulation iteration efficiency of stator interference.

[0038] Secondly, this application provides a powertrain, which includes an electric motor as described in the first aspect.

[0039] In this embodiment, the motor has multiple bolt bosses on the circumferential wall of the motor housing near the side used for fixing to the end cover of the motor. Each boss connects to at least two bolt bosses at the end away from the end cover, thereby dispersing the stress at the bolt boss's end away from the end cover and improving the problem of stress concentration and high stress at the root of the bolt boss. The stator interference stress is significantly reduced, effectively decreasing the number of iterations required for stator interference simulation. Connecting the bolt bosses at the end away from the end cover also enhances aluminum melt flow, reducing the probability of hot spots in the motor housing. This reduces the probability of air pockets forming at the intersection of the bolt boss's end away from the end cover and the motor housing, increasing the strength of the motor housing and thus improving the performance of the motor and powertrain.

[0040] Thirdly, this application provides an electric vehicle, which includes a frame and a powertrain as described in the second aspect, the powertrain being fixed to the frame.

[0041] The powertrain in this embodiment includes a motor. The motor housing has multiple bolt bosses on its circumferential wall near the side used for fixing to the motor's end cover. Each boss connects to at least two bolt bosses at the end away from the end cover, thus dispersing the stress at the bolt boss's root and mitigating stress concentration. This significantly reduces stator interference stress, effectively decreasing the number of iterations required for stator interference simulation. Connecting the bolt bosses to the end away from the end cover also enhances aluminum flow, reducing the probability of hot spots in the motor housing and decreasing the probability of air pockets at the intersection of the bolt boss's end away from the end cover and the motor housing. This improves the motor housing's strength, thereby enhancing the performance of the motor and powertrain, and optimizing overall vehicle performance. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the embodiments of this application will be described below.

[0043] Figure 1 This is a schematic diagram of an electric vehicle provided in an embodiment of this application;

[0044] Figure 2 This is a schematic diagram of a powertrain provided in an embodiment of this application;

[0045] Figure 3 This is another schematic diagram of the powertrain provided in the embodiments of this application;

[0046] Figure 4 This is a schematic diagram of a motor provided in an embodiment of this application;

[0047] Figure 5This is a schematic diagram of a motor housing provided in an embodiment of this application;

[0048] Figure 6 This is another schematic diagram of the motor housing provided in an embodiment of this application;

[0049] Figure 7 This is another schematic diagram of the motor housing provided in the embodiments of this application. Detailed Implementation

[0050] The technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0051] This application provides an electric motor. The motor housing is used to fix the stator of the motor and to house the rotor of the motor. The circumferential wall of the motor housing includes a plurality of bolt bosses and at least one protrusion. The plurality of bolt bosses are distributed circumferentially around the motor on the side of the circumferential wall of the motor housing opposite to the stator. The plurality of bolt bosses and at least one protrusion are radially opposite to the stator protrusion of the motor. The plurality of bolt bosses are used to fix the end cover of the motor. At least one protrusion is arranged adjacent to the plurality of bolt bosses along the axial direction of the motor. The side of each protrusion facing the end cover is connected to the end of at least two bolt bosses opposite to the end cover.

[0052] By setting multiple bolt bosses on the circumferential wall of the motor housing near the side used for fixing to the end cover of the motor, and setting at least one protrusion on the circumferential wall of the motor housing adjacent to the multiple bolt bosses along the axial direction of the motor, and making each protrusion connect to at least two bolt bosses away from the end cover, the stress at the root of the bolt bosses can be dispersed by the protrusions, thereby improving the problem of stress concentration and high stress at the root of the bolt bosses, which is beneficial to improving the stator interference simulation iteration efficiency.

[0053] The motor 11 provided in this application embodiment can be applied to the powertrain 10, and the powertrain 10 can be applied to the electric vehicle 1.

[0054] Figure 1 This is a schematic diagram of an electric vehicle 1 provided in an embodiment of this application.

[0055] In one embodiment, the electric vehicle 1 includes a powertrain 10, a frame 20, a power battery 30, and wheels 40, such as Figure 1 As shown, the frame 20 is used to fix the powertrain 10 and the power battery 30. The powertrain 10 is connected to the wheel 40 for transmission. The power battery 30 provides power to the powertrain 10, and the powertrain 10 can also charge the power battery 30.

[0056] Figure 2This is a schematic diagram of a powertrain 10 provided in an embodiment of this application. Figure 3 This is another schematic diagram of the powertrain 10 provided in the embodiments of this application. Figure 4 This is a schematic diagram of a motor 11 provided in an embodiment of this application.

[0057] In one embodiment, the powertrain 10 includes a motor 11 and a reducer 12, such as Figures 2 to 4 As shown, the motor 11 includes a motor housing 100, a motor shaft (not shown), a stator 200, and a rotor 300. The motor housing 100 is used to fix the stator 200 and to house the rotor 300. The rotor 300 is fixedly sleeved on the motor shaft. After receiving AC power, the stator 200 drives the rotor 300 to rotate, thereby driving the motor shaft to rotate. The reducer 12 includes a gear assembly (not shown), an input shaft (not shown), and an output shaft (not shown). The input shaft receives the power transmitted from the motor shaft of the motor 11 and transmits the power to the output shaft through the gear assembly. The output shaft is drive-connected to the half-shaft of the wheel 40 to drive the wheel 40 to rotate. In this embodiment, the motor 11 is a drive motor 11a, which is electrically connected to the power battery 30. The power battery 30 can supply power to the drive motor 11a through the motor controller 13.

[0058] In one embodiment, such as Figure 3 As shown, the powertrain 10 includes an engine 14 and an electric motor 11. The engine 14 is used to output power. For example, the engine 14 can be a combustion engine, including gasoline engines and diesel engines. In this embodiment, the electric motor 11 is a generator 11b, which is connected to the engine 14. The engine 14 provides power to the generator 11b, which converts the kinetic energy output by the engine 14 into electrical energy. The generator 11b is electrically connected to the power battery 30, and can charge the power battery 30 via a generator controller 15.

[0059] The motor housing and stator of the motor are fitted with an interference fit. The bolt bosses on the motor housing, which are used to fit with the end cover, have thick and uneven walls, causing stress concentration at the bolt bosses. This can easily lead to stress concentration and cracking of the motor housing, and can also cause hot spots and localized shrinkage cavities during the die-casting process, affecting the product's yield, strength, durability, and reliability. To reduce the stress at the root of the bolt bosses during the stator interference fit, additional material and large fillet radius are usually added to the bolt boss roots to reduce stress. However, this method suffers from low simulation iteration efficiency for stator interference fits.

[0060] By setting multiple bolt bosses on the circumferential wall of the motor housing near the side used for fixing to the end cover of the motor, and setting at least one protrusion on the circumferential wall of the motor housing adjacent to the multiple bolt bosses along the axial direction of the motor, and making each protrusion connect to at least two bolt bosses away from the end cover, the stress at the root of the bolt bosses can be dispersed by the protrusions, thereby improving the problem of stress concentration and high stress at the root of the bolt bosses, which is beneficial to improving the stator interference simulation iteration efficiency.

[0061] The motor 11 provided in the embodiments of this application will be described in detail below.

[0062] Figure 5 This is a schematic diagram of a motor housing 100 provided in an embodiment of this application.

[0063] In one embodiment, such as Figure 4 As shown, the motor housing 100 of the motor 11 is used to fix the stator 200 of the motor 11 and to house the rotor 300 of the motor 11, as follows: Figure 4 and Figure 5 As shown, the circumferential wall 100a of the motor housing 100 includes a plurality of bolt bosses 110 and at least one protrusion 120. The plurality of bolt bosses 110 are distributed at intervals around the circumferential C of the motor 11 on the side of the circumferential wall 100a of the motor housing 100 away from the stator 200. The plurality of bolt bosses 110 and at least one protrusion 120 protrude away from the stator 200 along the radial R of the motor 11. The plurality of bolt bosses 110 are used to fix the end cover 400 of the motor 11. Among them, at least one protrusion 120 is arranged adjacent to the plurality of bolt bosses 110 along the axial O of the motor 11. The side 121 of each protrusion 120 facing the end cover 400 is connected to the end 111 of at least two bolt bosses 110 away from the end cover 400.

[0064] In this embodiment, a plurality of bolt bosses 110 are distributed at intervals around the circumferential C of the motor 11 on the side of the circumferential wall 100a of the motor housing 100 away from the stator 200, so that the fixing between the plurality of bolt bosses 110 of the motor housing 100 and the end cover 400 is more stable.

[0065] In this embodiment of the application, at least one protrusion 120 and a plurality of bolt bosses 110 are arranged adjacent to each other along the axial direction O of the motor 11, so as to facilitate the connection of at least one protrusion 120 and a plurality of bolt bosses 110 along the axial direction O of the motor 11.

[0066] In this embodiment, since the motor housing 100 and stator 200 of motor 11 are fixed by a thermal interference fit, the bolt bosses 110 of the motor housing 100 used to fix to the end cover 400 have thick and uneven walls, which easily leads to stress concentration and high stress, affecting the product quality of the motor housing 100. By connecting the side 121 of each protrusion 120 facing the end cover 400 to the end 111 of at least two bolt bosses 110 facing away from the end cover 400, the stress at the end 111 of the bolt bosses 110 facing away from the end cover 400 can be dispersed by the protrusions 120, thereby improving the problem of stress concentration and high stress at the root of the bolt bosses 110. The reduced interference stress of the stator 200 also helps to improve the iteration efficiency of the interference simulation of the stator 200. The protrusion 120 connecting the bolt boss 110 away from the end 111 of the end cover 400 also helps to enhance the flow of aluminum liquid during the die casting process, reduce the probability of hot spots appearing in the die-cast motor housing 100, thereby reducing the probability of gas shrinkage cavities in the area where the end 111 of the bolt boss away from the end cover 400 intersects with the motor housing 100, and improving the strength of the motor housing 100.

[0067] In this application, multiple bolt bosses 110 are provided on the circumferential wall 100a of the motor housing 100 near the side used for fixing to the end cover 400 of the motor 11. Each boss 120 connects to at least two bolt bosses 110 at the end 111 away from the end cover 400. This allows the stress at the end 111 of the bolt bosses 110 away from the end cover 400 to be dispersed by the bosses 120, thereby improving the problem of stress concentration and high stress at the root of the bolt bosses 110. The interference stress of the stator 200 is significantly reduced, which can effectively reduce the number of iterations of interference simulation for the stator 200. The connection of the bolt bosses 110 at the end 111 away from the end cover 400 by the bosses 120 can also enhance the flow of molten aluminum, reduce the probability of hot spots in the die-cast motor housing 100, thereby reducing the probability of air shrinkage cavities in the area where the end 111 of the bolt bosses 110 away from the end cover 400 intersects with the motor housing 100, and improving the strength of the motor housing 100.

[0068] Figure 6 This is another schematic diagram of the motor housing 100 provided in the embodiments of this application.

[0069] In one embodiment, such as Figures 4 to 6 As shown, at least two bolt bosses 110 are aligned along the circumferential direction C of the motor 11, away from one end 111 of the end cover 400 along the axial direction O of the motor 11. The surface of each protrusion 120 facing the end cover 400 along the axial direction O of the motor 11 is flat and perpendicular to the axial direction O of the motor 11.

[0070] In this embodiment, at least two bolt bosses 110 are aligned along the axial direction O of the motor 11, away from the end cap 400, at one end 111, along the circumferential direction C of the motor 11. This facilitates the connection between the at least two bolt bosses 110 and the protrusion 120, and also allows the protrusion 120 to extend along the circumferential direction C of the motor 11. This allows the protrusion 120 to receive the stress from the bolt bosses 110 and the end cap 400 and disperse it along the circumferential direction C of the motor 11, which is more conducive to improving the stress concentration problem and thus increasing the number of interference simulation iterations of the stator 200.

[0071] In this embodiment, the surface of each protrusion 120 facing the end cover 400 along the axial direction O of the motor 11 is flat and perpendicular to the axial direction O of the motor 11, facilitating the connection between the protrusion 120 and the end 111 of the bolt boss 110 away from the end cover 400. It also facilitates the direct casting of the connection portion between the protrusion 120 and the bolt boss 110 during the die-casting process of the motor housing 100.

[0072] In one embodiment, such as Figure 4 and Figure 5 As shown, along the radial direction R of the motor 11, each protrusion 120 is opposite to one end 122 of the stator 200 and opposite to at least two bolt bosses 110 connected to the protrusion 120 on one side 112 of the stator 200.

[0073] In this embodiment, each protrusion 120 along the radial direction R of the motor 11 has one end 122 away from the stator 200 and one side 112 of the at least two bolt bosses 110 connected to it away from the stator 200. This allows the protrusion 120 along the radial direction R of the motor 11 to envelop the side 112 of the at least two bolt bosses 110 connected to it away from the stator 200. This facilitates the protrusion 120 to receive and disperse the stress at the end 111 of the bolt bosses 110 away from the end cover 400, which can effectively reduce the number of iterations of interference simulation of the stator 200.

[0074] In one embodiment, along the axial direction O of the motor 11, the end 122 of each protrusion 120 facing away from the stator 200 is flush with the side 112 of at least two bolt bosses 110 connected to the protrusion 120 facing away from the stator 200. This ensures that the protrusion 120 does not occupy additional radial space beyond the bolt bosses 110 of the motor housing 100 along the radial direction R of the motor 11, resulting in a smaller radial volume of the motor housing 100, which is beneficial for reducing the radial volume R of the motor 11.

[0075] In one embodiment, such as Figure 5 As shown, along the circumferential direction C of the motor 11, the length of each protrusion 120 is equal to the sum of the lengths of the two bolt protrusions 110a that are furthest apart among the at least two bolt protrusions 110 connected to it and the distance between them.

[0076] In the embodiments of this application, such as Figure 5 As shown, along the circumferential direction C of the motor 11, the length of each protrusion 120 is denoted as L1, and the sum of the lengths of the two bolt protrusions 110a that are furthest apart among the at least two bolt protrusions 110 connected to the protrusion 120 and the distance between them is denoted as L2. L1 = L2, so that the protrusion 120 will not occupy too much space of the motor housing 100 along the circumferential direction C of the motor 11, which is beneficial to making the volume of the motor housing 100 smaller.

[0077] Figure 7 This is another schematic diagram of the motor housing 100 provided in the embodiments of this application.

[0078] In one embodiment, such as Figure 7 As shown, along the circumferential direction C of the motor 11, the length of each protrusion 120 is greater than the sum of the lengths of the two farthest bolt protrusions 110a among the at least two bolt protrusions 110 connected to it and the distance between them.

[0079] In the embodiments of this application, such as Figure 7 As shown, along the circumferential direction C of the motor 11, the length of each protrusion 120 is L3. The sum of the lengths of the two bolt protrusions 110a that are furthest apart among the at least two bolt protrusions 110 connected to the protrusion 120 and the distance between them is denoted as L4. L3 > L4. The larger L3 makes the length of the protrusion 120 along the circumferential direction C of the motor 11 longer, which is more conducive to the protrusion 120 dispersing the stress at the end 111 of the bolt protrusion 110 away from the end cover 400 along the circumferential direction C of the motor 11, thereby increasing the number of interference simulation iterations of the stator 200.

[0080] In one embodiment, such as Figure 4 and Figure 7 As shown, at least one protrusion 120 is arranged adjacent to the first part 130 of the motor housing 100 along the circumferential direction C of the motor 11. The first part 130 protrudes away from the stator 200 along the radial direction R of the motor 11. At least one protrusion 120 is connected to the first part 130 at one end 123 near the first part 130 along the circumferential direction C of the motor 11.

[0081] In this embodiment, the first part 130 of the motor housing 100 protrudes away from the stator 200 along the radial direction R of the motor 11, such that at least one protrusion 120 is connected to the first part 130 at one end 123 near the first part 130 along the circumferential direction C of the motor 11. This allows the two ends 123 of the protrusion 120 along the circumferential direction C of the motor 11 to be independent of the bolt boss 110. This allows the stress received by the protrusion 120 at one end 111 of the bolt boss 110 away from the end cover 400 to be dispersed through the first part 130 of the motor housing 100, resulting in a better effect of stress release for the stator 200 and effectively reducing the number of iterations of the interference simulation of the stator 200.

[0082] In one embodiment, the first portion 130 of the motor housing 100 can be used to form an internal flow channel of the motor housing 100. In another embodiment, the first portion 130 of the motor housing 100 can be used to form the wall of a receiving groove, which can be used to receive the motor 11 or other structural components in the powertrain 10, such as three-phase connectors. In yet another embodiment, the first portion 130 of the motor housing 100 can also be used to form a retaining wall or a fixing boss for mounting and fixing the motor 11.

[0083] In one embodiment, such as Figure 7 As shown, each protrusion 120 includes two opposite ends 123 along the circumferential direction C of the motor 11. At least one end 123 of the two ends 123 is spaced apart from at least two bolt bosses 110 connected to the protrusion 120. One end 123a of the two ends 123 and one bolt boss 110b of the at least two bolt bosses 110 are arranged adjacent to each other along the circumferential direction C of the motor 11. The length of the protrusion 120 along the radial direction R of the motor 11 gradually decreases from the portion of it connected to a bolt boss 110b along the circumferential direction C of the motor 11 toward one end 123a.

[0084] In this embodiment, one end 123a of the two ends 123 is arranged adjacent to one of the bolt bosses 110 of at least two bolt bosses 110 along the circumferential C of the motor 11. The length of the protrusion 120 along the radial R of the motor 11 gradually decreases from the part connected to a bolt boss 110b along the circumferential C of the motor 11 toward one end 123a. This makes the length of one end 123a of the protrusion 120 along the radial R of the motor 11 smaller, which makes it easier for the protrusion 120 to disperse the stress received from the end 111 of the bolt boss 110 away from the end cover 400 from one end 123a of the protrusion 120 to the circumferential wall 100a of the motor housing 100 for release. This makes the interference stress release effect of the stator 200 better and can effectively reduce the number of iterations of interference simulation of the stator 200 of the product.

[0085] In one embodiment, such as Figure 5 and Figure 7As shown, the length of each protrusion 120 along the radial direction R of the motor 11 is greater than the length of the protrusion 120 along the axial direction O of the motor 11.

[0086] In this embodiment, the length of each protrusion 120 along the radial direction R of the motor 11 is greater than the length of the protrusion 120 along the axial direction O of the motor 11. The length of the protrusion 120 along the axial direction O of the motor 11 is smaller, so that while satisfying the requirement of dispersing the stress at the end 111 of the bolt boss 110 away from the end cover 400, the axial space occupied by the protrusion 120 in the motor housing 100 is smaller. The smaller length of the protrusion 120 along the axial direction O of the motor 11 also helps to save materials and reduce weight.

[0087] In one embodiment, such as Figure 5 and Figure 7 As shown, the outer diameter of each bolt boss 110 connected to the protrusion 120 gradually decreases from its two opposite ends toward the middle along the axial direction O of the motor 11. The minimum cross-sectional area of ​​each bolt boss 110 connected to the protrusion 120 is greater than the cross-sectional area of ​​the fixing hole 113 in each bolt boss 110.

[0088] In this embodiment, the outer diameter of each bolt boss 110 connected to the protrusion 120 gradually decreases along the axial direction O of the motor 11 from its two opposite ends toward the middle. This avoids excessive thickness at the root of the bolt boss 110 and makes it easier for each bolt boss 110 to distribute its stress to the protrusion 120, which is beneficial for stress release. It also helps to save material and reduce weight in the motor housing 100.

[0089] In this embodiment, the minimum cross-sectional area of ​​each bolt boss 110 connected to the protrusion 120 is greater than the cross-sectional area of ​​the fixing hole 113 in each bolt boss 110, so that the bolt boss 110 can be fixed to the end cover 400 without affecting the fixing strength of the bolt boss 110 and the end cover 400 while having the advantage of dispersing stress, which is beneficial to improving the performance of the motor 11.

[0090] In one embodiment, such as Figure 5 and Figure 7 As shown, the area of ​​each bolt boss 110 connected to the protrusion 120 where one end 111 away from the end cover 400 is connected to the protrusion 120 is greater than the cross-sectional area of ​​the bolt boss 110 other than one end 111 along the axial direction O perpendicular to the motor 11.

[0091] In this embodiment, the area of ​​the end 111 of each bolt boss 110 connected to the protrusion 120 that is away from the end cover 400 and connected to the protrusion 120 is larger. This allows for better transfer of stress from the bolt boss 110 to the protrusion 120, resulting in more uniform stress distribution and improved stress concentration. This reduces the number of iterations required for interference simulation of the product stator 200.

[0092] In one embodiment, such as Figure 4 and Figure 5 As shown, at least two adjacent bolt bosses 110 connected to the protrusion 120, a portion of the protrusion 124 between the two adjacent bolt bosses 110, and the outer surface of the circumferential wall 100a of the motor housing 100 form a groove 140. The radial bottom 141 of the groove 140 is recessed towards the stator 200 along the radial R of the motor 11. The groove width of the groove 140 between the two adjacent bolt bosses 110 along the circumferential C of the motor 11 is greater than the length of the portion of the protrusion 124 between the two adjacent bolt bosses 110.

[0093] In this embodiment, a groove 140 is formed by the outer surfaces of two adjacent bolt bosses 110 connected to the protrusion 120, a portion of the protrusion 124 between the two adjacent bolt bosses 110, and the circumferential wall 100a of the motor housing 100. The radial bottom 141 of the groove 140 is recessed towards the stator 200 along the radial R of the motor 11, which helps to reduce the thickness of the circumferential wall 100a of the motor housing 100 between the two adjacent bolt bosses 110, thus saving materials.

[0094] In the embodiments of this application, such as Figure 5 As shown, the groove width of the groove 140 between two adjacent bolt bosses 110 along the circumferential direction C of the motor 11 is denoted as L5, and the length of the portion of the protrusion 124 between two adjacent bolt bosses 110 is denoted as L6, where L5 > L6. The larger L5 facilitates the distribution of stress on the two adjacent bolt bosses 110 by the groove 140, resulting in a better effect on the release of interference stress in the stator 200 and effectively reducing the number of iterations in the interference simulation of the stator 200.

[0095] In one embodiment, such as Figure 5 and Figure 6 As shown, along the axial direction O of the motor 11, a portion 150 of the motor housing 100 distributed on the side 121 of the protrusion 120 facing the end cover 400 shares a draft mold (not shown), and another portion 160 of the motor housing 100 distributed on the other side 125 of the protrusion 120 away from the end cover 400 shares another draft mold (not shown). The drafting direction of one draft mold and the drafting direction of the other draft mold intersect the axial direction O of the motor 11.

[0096] In this embodiment, along the axial direction O of the motor 11, a portion 150 of the motor housing 100 distributed on the side 121 of the protrusion 120 facing the end cover 400 shares a single draft mold, while another portion 160 of the motor housing 100 distributed on the other side 125 of the protrusion 120 away from the end cover 400 shares a separate draft mold. The protrusion 120 can solve the mold parting problem of the motor housing 100, thereby improving the manufacturability of the product. In one embodiment, the draft direction of one draft mold is the same as that of the other draft mold. In another embodiment, the draft direction of one draft mold intersects with that of the other draft mold.

[0097] In one embodiment, such as Figure 4 As shown, the radial protrusion 120 of the motor 11 is arranged opposite to the stator core 210 of the stator 200, and the protrusion 120 is arranged along the axial direction O of the motor 11 between the two opposite ends 211 of the stator core 210 along the axial direction O of the motor 11.

[0098] In this embodiment, the radial protrusion 120 of the motor 11 is arranged opposite to the stator core 210 of the stator 200, so that the protrusion 120 can better receive the stress generated by the stator core 210 on the motor housing 100, thereby making it more advantageous to release the interference stress of the stator 200 by using the protrusion 120, which can effectively improve the interference simulation iteration efficiency of the stator 200.

[0099] The electric motor, powertrain, and electric vehicle provided in the embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and embodiments of this application. The description of the embodiments above is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in specific embodiments and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. An electric motor, characterized in that, The motor housing of the motor is used to fix the stator of the motor and to accommodate the rotor of the motor. The circumferential wall of the motor housing includes a plurality of bolt bosses and at least one protrusion. The plurality of bolt bosses are distributed at intervals around the circumference of the motor on the side of the circumferential wall of the motor housing opposite to the stator. The plurality of bolt bosses and the at least one protrusion are radially opposite to the stator protrusion of the motor. The plurality of bolt bosses are used to fix the end cover of the motor, wherein: The at least one protrusion and the plurality of bolt bosses are arranged adjacent to each other along the axial direction of the motor, and each of the protrusions is connected to the side of at least two bolt bosses facing away from the end cover.

2. The motor according to claim 1, characterized in that, The at least two bolt bosses are aligned circumferentially with respect to one end of the end cover along the axial direction of the motor. The surface of each of the protrusions facing the side of the end cap along the axial direction of the motor is planar and perpendicular to the axial direction of the motor.

3. The motor according to claim 1, characterized in that, Along the radial direction of the motor, each of the protrusions is opposite to one end of the stator and opposite to one side of the at least two bolt bosses connected to the protrusion.

4. The motor according to claim 2, characterized in that, Along the radial direction of the motor, each of the protrusions is opposite to one end of the stator and opposite to one side of the at least two bolt bosses connected to the protrusion.

5. The motor according to any one of claims 1-4, characterized in that, Along the circumference of the motor, the length of each protrusion is equal to the sum of the lengths of the two bolt protrusions that are furthest apart among the at least two bolt protrusions connected to it and the distance between them.

6. The motor according to any one of claims 1-4, characterized in that, Along the circumference of the motor, the length of each of the protrusions is greater than the sum of the lengths of the two bolt protrusions furthest apart among the at least two bolt protrusions connected to it and the distance between them.

7. The motor according to claim 6, characterized in that, At least one of the protrusions is arranged adjacent to a first portion of the motor housing along the circumference of the motor, the first portion being radially away from the stator protrusion, and the at least one protrusion being connected to the first portion at one end along the circumference of the motor near the first portion.

8. The motor according to claim 6, characterized in that, Each of the protrusions includes two opposite ends along the circumference of the motor, at least one of the ends being spaced apart from the at least two bolt bosses connected to the protrusion, the end of the protrusion being adjacent to one of the bolt bosses along the circumference of the motor at a distance, and the radial length of the protrusion along the motor gradually decreasing from the portion of it connecting to the bolt boss toward the end along the circumference of the motor.

9. The motor according to any one of claims 1-4 or 7-8, characterized in that, The length of each of the protrusions along the radial direction of the motor is greater than the length of the protrusion along the axial direction of the motor.

10. The motor according to claim 5, characterized in that, The length of each of the protrusions along the radial direction of the motor is greater than the length of the protrusion along the axial direction of the motor.

11. The motor according to any one of claims 1-4, 7-8, or 10, characterized in that, The outer diameter of each bolt boss connected to the protrusion gradually decreases along the axial direction of the motor from its two opposite ends toward the middle, and the minimum cross-sectional area of ​​each bolt boss connected to the protrusion is greater than the cross-sectional area of ​​the fixing hole in each bolt boss.

12. The motor according to claim 9, characterized in that, The outer diameter of each bolt boss connected to the protrusion gradually decreases along the axial direction of the motor from its two opposite ends toward the middle, and the minimum cross-sectional area of ​​each bolt boss connected to the protrusion is greater than the cross-sectional area of ​​the fixing hole in each bolt boss.

13. The motor according to claim 11, characterized in that, The area of ​​each bolt boss connected to the protrusion at the end opposite to the end cap that is connected to the protrusion is greater than the cross-sectional area of ​​the bolt boss other than at the end along the direction perpendicular to the axial direction of the motor.

14. The motor according to claim 12, characterized in that, The area of ​​each bolt boss connected to the protrusion at the end opposite to the end cap that is connected to the protrusion is greater than the cross-sectional area of ​​the bolt boss other than at the end along the direction perpendicular to the axial direction of the motor.

15. The motor according to claim 11, characterized in that, The outer surface of the outer wall of the circumferential wall of the motor housing and the two adjacent bolt bosses connected to the protrusion, as well as a portion of the protrusion and a portion of the motor housing, encloses a groove. The radial bottom of the groove is recessed toward the stator along the radial direction of the motor. The groove width between the two adjacent bolt bosses along the circumferential direction of the motor is greater than the length of the portion of the protrusion between the two adjacent bolt bosses.

16. The motor according to claim 14, characterized in that, The outer surface of the outer wall of the circumferential wall of the motor housing and the two adjacent bolt bosses connected to the protrusion, as well as a portion of the protrusion and a portion of the motor housing, encloses a groove. The radial bottom of the groove is recessed toward the stator along the radial direction of the motor. The groove width between the two adjacent bolt bosses along the circumferential direction of the motor is greater than the length of the portion of the protrusion between the two adjacent bolt bosses.

17. The motor according to any one of claims 1-4, 7-8, 10 or 12-16, characterized in that, Along the axial direction of the motor, a portion of the motor housing distributed on the side of the protrusion facing the end cover shares a draft die, and another portion of the motor housing distributed on the other side of the protrusion away from the end cover shares a draft die. The drafting directions of the one draft die and the other draft die intersect the axial direction of the motor.

18. The motor according to any one of claims 1-4, 7-8, 10 or 12-16, characterized in that, The protrusions are arranged opposite to the stator core of the stator along the radial direction of the motor, and the protrusions are arranged between the two opposite ends of the stator core along the axial direction of the motor.

19. A powertrain, characterized in that, The powertrain includes an electric motor as described in any one of claims 1-18.

20. An electric vehicle, characterized in that, The electric vehicle includes a frame and a powertrain as described in claim 19, the powertrain being fixed to the frame.

Images