Electric power steering motor, electric power steering system and vehicle

Abstract

The utility model provides an electric power steering motor, an electric power steering system and a vehicle. The electric power steering motor comprises a rotor core which comprises a plurality of core segments, and the plurality of core segments are superposed; the rotating shaft penetrates through the shaft hole; the rotating shaft is sleeved with the first bearing, and the first bearing is in interference fit with the rotating shaft; the second bearing sleeves the rotating shaft, at least one of the first bearing and the second bearing is a four-point contact ball bearing, and the second bearing is in clearance fit with the rotating shaft; the first elastic part is arranged on the rotating shaft in a sleeving mode, the first bearing is located between the first elastic part and the rotor iron core, and the first elastic part is used for applying axial pre-tightening force to the first bearing; the end face, facing the rotor core, of the second bearing is connected with the peripheral wall of the rotating shaft through a welding fixing part. The welding fixing part is matched with the rotating shaft so as to limit the second bearing in the axial direction, the radial direction and the circumferential direction of the rotating shaft. The structural rigidity of the motor is improved, and the overall deformation resistance of the motor is enhanced.

Description

Technical Field

[0001] The present application relates to the technical field of motors, and more particularly, to an electric power steering motor, an electric power steering system, and a vehicle. Background Art

[0002] People's requirements for a low-noise and comfortable driving environment are becoming increasingly stringent. In the related art, the vibration noise of the motor of new energy vehicles is relatively large, resulting in a relatively large noise during vehicle driving, which seriously affects the driving experience of users. Utility Model Content

[0003] The present application aims to solve at least one of the technical problems existing in the prior art or related art.

[0004] To this end, a first aspect of the present application provides an electric power steering motor.

[0005] A second aspect of the present application provides an electric power steering system.

[0006] A third aspect of the present application provides a vehicle.

[0007] In view of this, the present application provides an electric power steering motor, including: a rotor core, the rotor core includes a plurality of core segments, the plurality of core segments are stacked, any two adjacent core segments are arranged offset in the clockwise direction or the counterclockwise direction, the rotor core is provided with a shaft hole, and the shaft hole axially penetrates through the plurality of core segments along the rotor core; a rotating shaft, passing through the shaft hole; a first bearing, sleeved on the rotating shaft, and the first bearing is in interference fit with the rotating shaft; a second bearing, sleeved on the rotating shaft, the rotor core is located between the first bearing and the second bearing, at least one of the first bearing and the second bearing is a four-point contact ball bearing, and the second bearing is in clearance fit with the rotating shaft; a first elastic part, sleeved on the rotating shaft, and the first bearing is located between the first elastic part and the rotor core, and the first elastic part is used to apply an axial pre-tightening force to the first bearing; the end face of the second bearing facing the rotor core is connected to the outer peripheral wall of the rotating shaft through a welding fixing part.

[0008] An electric power steering motor provided by the present application includes a rotor core, a rotating shaft, a first bearing, a second bearing, a first elastic part, and a welding fixing part.

[0009] The rotor core includes a plurality of core segments stacked along the axis of the rotor core. Among them, any two adjacent core segments are arranged offset in the clockwise direction, or any two adjacent core segments are arranged offset in the counterclockwise direction. That is, any two adjacent core segments are arranged offset in the circumferential direction of the rotor core to form a rotor skew pole. The segmented modular setting of the rotor core has the advantages of being convenient for installation and maintenance, and a skew pole can be formed between the plurality of core segments.

[0010] Defining that any two adjacent iron core segments are arranged offset in the clockwise or counterclockwise direction can reduce the cogging torque and torque ripple, thereby reducing electromagnetic vibration. That is to say, by dividing the rotor iron core into multiple iron core segments and arranging any two adjacent iron core segments offset in the clockwise or counterclockwise direction, the specific harmonic content in the electric power steering motor can be effectively suppressed, the torque ripple and cogging torque of the electric power steering motor can be improved, and thus the vibration and noise of the electric power steering motor can be reduced.

[0011] Further, the rotor iron core is provided with a shaft hole, the shaft hole axially penetrates through multiple iron core segments along the rotor iron core, a rotating shaft is inserted into the shaft hole, a first bearing is sleeved on the rotating shaft, a second bearing is sleeved on the rotating shaft, the first bearing is located outside the rotor iron core, and the second bearing is located outside the rotor iron core. Among them, at least one of the first bearing and the second bearing is a four-point contact ball bearing. That is, the first bearing is a four-point contact ball bearing, and / or the second bearing is a four-point contact ball bearing.

[0012] The four-point contact ball bearing can enhance the overall anti-deformation ability of the electric power steering motor, is beneficial to improving the structural stiffness of the electric power steering motor, can reduce the axial end play when the electric power steering motor works. In this way, the vibration performance during the operation of the electric power steering motor is further improved, the vibration and noise of the electric power steering motor can be further reduced, and the service performance and market competitiveness of the electric power steering motor are greatly improved.

[0013] Optionally, when both the first bearing and the second bearing are four-point contact ball bearings, that is, four-point contact ball bearings are arranged on both axial sides of the rotor iron core. In this way, the mating area and mating angle between the first bearing, the second bearing and the rotating shaft are increased, the overall anti-deformation ability of the rotor can be further enhanced, the structural stiffness of the electric power steering motor can be further improved, the axial end play when the electric power steering motor works can be reduced. In this way, the vibration performance during the operation of the electric power steering motor is further improved, and the vibration and noise of the electric power steering motor can be further reduced.

[0014] Among them, after the motor is assembled, the first bearing is located between the first elastic part and the rotor iron core. By squeezing the first elastic part, the first elastic part applies an axial pre-tightening force to the first bearing to ensure the structural stiffness of the electric power steering motor, which is beneficial to reducing the axial end play when the electric power steering motor works.

[0015] Among them, the second bearing has a clearance fit with the rotating shaft, and the end face of the second bearing facing the rotor iron core is connected to the outer peripheral wall of the rotating shaft through a welding fixing part. That is, the welding fixing part firmly assembles the second bearing and the rotating shaft together.

[0016] The welding fixing part and the rotating shaft cooperate to limit the second bearing axially, radially and circumferentially along the rotating shaft. This improves the structural stiffness of the electric power steering motor, can reduce the axial play of the electric power steering motor during operation, and enhances the overall anti-deformation ability of the electric power steering motor. In this way, the vibration performance of the electric power steering motor during operation is further improved, the vibration noise of the electric power steering motor can be further reduced, and the service performance and market competitiveness of the electric power steering motor are greatly improved.

[0017] In addition, the second bearing and the rotating shaft are in clearance fit, and the welding fixing part firmly assembles the second bearing and the rotating shaft. This setting can reduce the influence on the radial clearance of the second bearing and ensure the radial clearance of the second bearing. In this way, it is beneficial to reduce the frictional torque of the electric power steering motor during operation. That is to say, this setting takes into account reducing the vibration noise of the electric power steering motor and reducing the frictional torque of the electric power steering motor, improving the service performance and market competitiveness of the product.

[0018] It can be understood that when there is no load, the inner ring of the second bearing is fixed, and the displacement of the outer ring of the second bearing relative to the fixed inner ring from one extreme position to another extreme position along the radial direction of the rotor core is denoted as the radial clearance of the second bearing.

[0019] It can be understood that when there is no load, the inner ring of the first bearing is fixed, and the displacement of the outer ring of the first bearing relative to the fixed inner ring from one extreme position to another extreme position along the axial direction of the rotor core is denoted as the axial clearance of the first bearing. Or, when there is no load, the outer ring of the first bearing is fixed, and the displacement of the inner ring of the first bearing relative to the fixed outer ring from one extreme position to another extreme position along the axial direction of the rotor core is denoted as the axial clearance of the first bearing.

[0020] According to the above-mentioned electric power steering motor of the present application, it may further have the following additional technical features:

[0021] In some embodiments, optionally, when one of the first bearing and the second bearing is a four-point contact ball bearing, the second bearing is a four-point contact ball bearing.

[0022] In this embodiment, the structures of the first bearing and the second bearing are further defined.

[0023] So that when one of the first bearing and the second bearing is a four-point contact ball bearing, the second bearing is a four-point contact ball bearing and the first bearing is a non-four-point contact ball bearing.

[0024] In some embodiments, optionally, the welding fixing part is arranged around the rotating shaft.

[0025] In this embodiment, the installation position of the welding fixing part is further defined.

[0026] Optionally, the welding fixing part is arranged around the rotating shaft, that is, the welding fixing part is an annular structure, and the connection between the welding fixing part and the rotating shaft and the second bearing is welded around the circumference of the rotating shaft. That is, the circumference of the rotating shaft and the second bearing is fully welded. This arrangement can increase the matching area and matching angle between the welding fixing part and the rotating shaft and the second bearing, which is conducive to improving the stability and reliability of the assembly of the rotating shaft and the second bearing, so as to enhance the overall anti-deformation ability of the electric power steering motor and reduce the friction torque of the electric power steering motor.

[0027] In some embodiments, optionally, there are multiple welding fixing parts, and the multiple welding fixing parts are arranged at intervals along the circumference of the rotating shaft.

[0028] In this embodiment, the location of the welding fixing portion is further defined.

[0029] Optionally, there are multiple welding fixing parts, and the multiple welding fixing parts are arranged at intervals along the circumference of the rotating shaft. This arrangement can effectively fix the rotating shaft and the second bearing from multiple directions and multiple angles, can ensure the balance and consistency of the forces at different positions of the second bearing, can ensure the radial clearance of the second bearing, can enhance the overall anti-deformation ability of the electric power steering motor, and can reduce the friction torque of the electric power steering motor. In addition, this arrangement is conducive to reducing the deformation amount at the connection between the rotating shaft and the second bearing, is conducive to reducing the difficulty of the process of connecting the rotating shaft and the second bearing, and is conducive to improving the assembly efficiency of the motor.

[0030] In some embodiments, optionally, the electric power steering motor further includes: a shell, in which a first bearing cavity and a second bearing cavity are provided; a rotor core, a rotating shaft, a first bearing, a second bearing and a first elastic part are all provided in the shell, the first bearing is located in the first bearing cavity, and the second bearing is located in the second bearing cavity; the first elastic part abuts between a side of the first bearing facing away from the rotor core and a cavity wall of the first bearing cavity.

[0031] In this embodiment, the electric power steering motor further includes a housing.

[0032] The rotor core, the rotating shaft, the first bearing, the second bearing and the first elastic part are all arranged in the housing. That is, the housing serves as a mounting carrier for the rotor core, the rotating shaft, the first bearing, the second bearing and the first elastic part, and has the function of mounting and fixing the rotor core, the rotating shaft, the first bearing, the second bearing and the first elastic part to ensure the matching dimensions of the rotor core, the rotating shaft, the first bearing, the second bearing and the first elastic part.

[0033] A first bearing cavity and a second bearing cavity are provided in the housing. The first bearing cavity is used for installing a first bearing, and the second bearing cavity is used for installing a second bearing.

[0034] The first bearing is interference fit with the rotating shaft, the first elastic part is arranged in the first bearing cavity, the first bearing is located between the first elastic part and the rotor core, the first elastic part abuts against the first bearing, and the first elastic part abuts against the cavity wall of the first bearing cavity. In other words, the first elastic part abuts between the side of the first bearing away from the rotor core and the cavity wall of the first bearing cavity. The first elastic part is used to apply an axial preload force to the first bearing so that the first bearing is firmly assembled on the rotating shaft.

[0035] It can be understood that after the motor is assembled, the first elastic part is located between the first bearing and the wall of the first bearing cavity. By squeezing the first elastic part, the first elastic part applies an axial preload to the first bearing to ensure the structural stiffness of the electric power steering motor, which is beneficial to reducing the axial movement of the electric power steering motor during operation.

[0036] It can be understood that the cavity wall of the first bearing cavity has the function of limiting the first bearing. Specifically, the cavity wall of the first bearing cavity is used to limit the first bearing in the radial direction of the rotating shaft.

[0037] In addition, the first bearing and the rotating shaft are interference fit to limit the first bearing in the axial and radial directions of the rotating shaft.

[0038] In some embodiments, optionally, a slot is further provided in the shell, the slot is located on the side of the second bearing cavity facing the first bearing cavity, and the slot is connected to the second bearing cavity; the electric power steering motor also includes a second elastic part, the second elastic part is provided in the slot, the second elastic part is arranged around the rotating shaft, and the second elastic part abuts against the second bearing, and the second elastic part is used to limit the axial displacement of the second bearing.

[0039] In this embodiment, a card slot is further provided in the housing.

[0040] The clamping groove is located on a side of the second bearing cavity facing the first bearing cavity, and the clamping groove is communicated with the second bearing cavity.

[0041] The electric power steering motor also includes a second elastic part, and the slot is used to install and fix the second elastic part. The second elastic part is arranged in the slot, the second elastic part is arranged around the rotating shaft, and the second elastic part abuts against the second bearing. The second elastic part is used to limit the second bearing along the axial direction of the rotating shaft to ensure the matching size of the second bearing and the rotating shaft. It is beneficial to improve the stability and reliability of the assembly of the rotating shaft and the second bearing, so as to enhance the overall anti-deformation ability of the electric power steering motor and reduce the friction torque of the electric power steering motor.

[0042] The welding fixing part and the second elastic part cooperate to ensure the radial clearance of the second bearing while reducing the vibration and noise of the electric power steering motor, which can enhance the anti-deformation ability of the motor and reduce the frictional torque of the electric power steering motor. That is to say, this setting takes into account both reducing the vibration and noise of the electric power steering motor and reducing the frictional torque of the electric power steering motor, improving the performance and market competitiveness of the product.

[0043] In some embodiments, optionally, along the axial direction of the rotating shaft, the width of the card slot is smaller than the width of the second elastic part.

[0044] In this embodiment, the mating structure of the card slot and the second elastic part is further defined.

[0045] Specifically, along the axial direction of the rotating shaft, the width of the card slot is smaller than the width of the second elastic part. The second elastic part is in interference fit with the card slot, and the second elastic part is extruded, and the second elastic part is effectively restricted from displacing axially on the rotating shaft through its own hoop deformation.

[0046] In some embodiments, optionally, a convex part is provided in the second bearing cavity, and the convex part abuts against the outer peripheral wall of the second bearing.

[0047] In this embodiment, the mating structure of the housing and the second bearing is further defined.

[0048] Specifically, a convex part is provided in the second bearing cavity, and the convex part abuts against the outer peripheral wall of the second bearing. Specifically, the convex part is riveted on the outside of the second bearing, and the second bearing is welded to the rotating shaft. The convex part and the welding fixing part cooperate to limit the second bearing axially, radially and circumferentially along the rotating shaft. To improve the structural stiffness of the electric power steering motor, the axial end play during the operation of the electric power steering motor can be reduced, and the overall anti-deformation ability of the electric power steering motor can be enhanced. In this way, the vibration performance during the operation of the electric power steering motor is further improved, the vibration and noise of the electric power steering motor can be further reduced, and the performance and market competitiveness of the electric power steering motor are greatly improved.

[0049] In some embodiments, optionally, the rotor core is further provided with a plurality of magnet slots, the plurality of magnet slots are arranged at intervals along the circumferential direction of the rotating shaft, and the magnet slots are located between the shaft hole and the outer peripheral wall of the rotor core; the electric power steering motor further includes a plurality of permanent magnets, and each permanent magnet is arranged in one magnet slot.

[0050] In this embodiment, the specific structure of the electric power steering motor is further defined.

[0051] The part of the rotor core located between the shaft hole and the outer peripheral wall of the rotor core is provided with a plurality of magnet slots, and the plurality of magnet slots are arranged at intervals along the circumferential direction of the rotating shaft.

[0052] The electric power steering motor further includes a plurality of permanent magnets, and each permanent magnet is disposed in a magnet slot. That is, the plurality of permanent magnets are disposed on the rotor core, and the plurality of permanent magnets are arranged at intervals in the circumferential direction of the rotating shaft. The permanent magnets are located between the shaft hole and the outer peripheral wall of the rotor core.

[0053] In some embodiments, optionally, along the axial direction of the rotating shaft, the length of the permanent magnet is less than or equal to the length of the iron core section.

[0054] In this embodiment, the mating structure of the rotor core and the permanent magnet is further defined.

[0055] Specifically, along the axial direction of the rotating shaft, the length of the permanent magnet is less than or equal to the length of the iron core section.

[0056] The iron core section has the function of protecting the permanent magnet. In this way, the probability of squeezing the permanent magnet and thus causing damage to the permanent magnet can be reduced.

[0057] If the length of the permanent magnet is greater than the length of the iron core section along the axial direction of the rotating shaft, then a part of the permanent magnet is likely to protrude from the iron core section. This setting is likely to cause the permanent magnet to be squeezed and damaged, and the service performance of the motor cannot be guaranteed.

[0058] In some embodiments, optionally, the rotor core is further provided with a plurality of weight-reducing holes. The plurality of weight-reducing holes are arranged at intervals in the circumferential direction of the rotating shaft. The weight-reducing holes are located between the rotating shaft and the permanent magnets; the number of weight-reducing holes is greater than or equal to the number of pole pairs of the electric power steering motor.

[0059] In this embodiment, the structure of the rotor core is further defined such that the rotor core is provided with a plurality of weight-reducing holes. The plurality of weight-reducing holes are arranged at intervals around the circumferential direction of the rotating shaft. The weight-reducing holes have the function of reducing the overall weight of the motor.

[0060] In addition, any two adjacent iron core sections are arranged staggeredly in the clockwise direction or in the counterclockwise direction. That is, any two adjacent iron core sections are arranged staggeredly in the circumferential direction of the rotor core to form a skewed pole of the rotor. The weight-reducing holes can be used as a positioning basis to assemble the rotor core, providing a reliable structural support for ensuring the formation of the skewed pole of the rotor.

[0061] Furthermore, the number of weight-reducing holes is greater than or equal to the number of pole pairs of the electric power steering motor, and the plurality of weight-reducing holes are arranged at intervals in the circumferential direction of the rotating shaft. In this way, when assembling the rotor core, the plurality of iron core sections can be positioned from multiple directions and multiple angles, and the fitting accuracy of the plurality of iron core sections can be ensured.

[0062] Optionally, the number of weight-reducing holes is equal to the number of pole pairs of the electric power steering motor.

[0063] Optionally, weight-reducing holes are provided on the magnetic pole center line and / or the inter-pole center line of the rotor core. This can reduce the moment of inertia and the overall weight of the electric power steering motor while ensuring that the performance of the electric power steering motor is not affected.

[0064] In some embodiments, optionally, at least a part of the hole wall of the shaft hole is in interference fit with the rotating shaft.

[0065] In this embodiment, the mating structure between the rotor core and the rotating shaft is defined.

[0066] At least a part of the hole wall of the shaft hole is in interference fit with the rotating shaft. That is, a part of the hole wall of the shaft hole is in interference fit with the rotating shaft. Or the entire hole wall of the shaft hole is in interference fit with the rotating shaft.

[0067] This setting can ensure the mating structure between the rotating shaft and the rotor core and prevent the separation of the rotating shaft and the rotor core.

[0068] When a part of the hole wall of the shaft hole is in interference fit with the rotating shaft, the contact area between the shaft hole and the rotating shaft can be reduced. That is, while ensuring the use requirement of the interference fit between the rotating shaft and the shaft hole, the radial force formed by the interference fit between the shaft hole and the rotating shaft can be reduced due to the reduction of the contact area between the shaft hole and the rotating shaft. This can reduce the influence of the radial force on the bonding force between the laminations of the rotor core, which is beneficial to reducing the probability of deformation of the laminations of the rotor core and further reducing the probability of loosening of multiple laminations of the rotor core.

[0069] Optionally, the hole wall of the shaft hole is a convex-concave wall. The protrusions of the convex-concave wall are in interference fit with the rotating shaft, and the depressions of the convex-concave wall are arranged separately from the rotating shaft. The protrusions and depressions of the convex-concave wall are arranged alternately, and both the protrusions and the depressions extend along the axial direction of the rotating shaft.

[0070] In some embodiments, optionally, the axial clearance of the second bearing is less than or equal to 0.1 mm.

[0071] In this embodiment, the value range of the axial clearance σ of the second bearing is further defined such that σ ≤ 0.1 mm. In this way, the axial vibration of the electric power steering motor can be further optimized to further optimize the vibration noise of the electric power steering motor.

[0072] It can be understood that when there is no load, the inner ring of the second bearing is fixed, and the displacement of the outer ring of the second bearing relative to the fixed inner ring from one extreme position to another extreme position along the axial direction of the rotor core is recorded as the axial clearance σ of the second bearing.

[0073] The second aspect of the present invention proposes an electric power steering system, including: the electric power steering motor as in the first aspect.

[0074] The electric power steering system provided by the present utility model includes the electric power steering motor as in the first aspect. Therefore, it has all the beneficial effects of the above-mentioned electric power steering motor, and will not be elaborated one by one here.

[0075] The third aspect of the present utility model provides a vehicle, including: the electric power steering motor as in the first aspect; or the electric power steering system as in the second aspect.

[0076] The vehicle provided by the present utility model includes the electric power steering motor as in the first aspect, or includes the electric power steering system as in the second aspect. Therefore, it has all the beneficial effects of the above-mentioned electric power steering motor or electric power steering system, and will not be elaborated one by one here.

[0077] It should be noted that the vehicle can be a new energy vehicle. New energy vehicles include pure electric vehicles, range-extended electric vehicles, hybrid vehicles, fuel cell electric vehicles, hydrogen engine vehicles, etc.

[0078] The vehicle can also be a fuel vehicle and a hybrid vehicle.

[0079] The additional aspects and advantages of the present application will become apparent in the following description section, or be learned through the practice of the present application. Description of the Drawings

[0080] The above and / or additional aspects and advantages of the present application will become apparent and be easily understood from the description of the embodiments in conjunction with the following drawings, where:

[0081] Figure 1 The structural schematic diagram of the first part of the electric power steering motor according to an embodiment of the present application is shown;

[0082] Figure 2 The structural schematic diagram of the second part of the electric power steering motor according to an embodiment of the present application is shown;

[0083] Figure 3 The structural schematic diagram of the third part of the electric power steering motor according to an embodiment of the present application is shown;

[0084] Figure 4 The structural schematic diagram of the second bearing according to an embodiment of the present application is shown;

[0085] Figure 5 The structural schematic diagram of the fourth part of the electric power steering motor according to an embodiment of the present application is shown;

[0086] Figure 6 The structural schematic diagram of the fifth part of the electric power steering motor according to an embodiment of the present application is shown;

[0087] Figure 7 Partial structural schematic diagram of the electric power steering motor according to the first embodiment of the present application;

[0088] Figure 8 Partial structural schematic diagram of the electric power steering motor according to the second embodiment of the present application.

[0089] Among them, Figures 1 to 8 The corresponding relationship between the reference numerals and the component names is as follows:

[0090] 10 Electric power steering motor, 100 Rotor core, 110 Core segment, 120 Shaft hole, 130 Magnet slot, 140 Weight reduction hole, 200 Rotating shaft, 300 First bearing, 400 Second bearing, 500 First elastic part, 600 Welding fixing part, 700 Housing, 710 First bearing cavity, 720 Second bearing cavity, 722 Protrusion, 730 Card slot, 800 Second elastic part, 900 Permanent magnet. Detailed implementation manners

[0091] In order to more clearly understand the above objects, features and advantages of the present application, the present application will be further described in detail below with reference to the drawings and specific implementation manners. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments may be combined with each other.

[0092] Many specific details are set forth in the following description in order to fully understand the present application. However, the present application may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present application is not limited by the specific embodiments disclosed below.

[0093] Next, refer to Figures 1 to 8 Describe the electric power steering motor 10, the electric power steering system and the vehicle according to some embodiments of the present application.

[0094] As Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 shown, an electric power steering motor 10 according to some embodiments of the present application includes a rotor core 100, a rotating shaft 200, a first bearing 300, a second bearing 400, a first elastic part 500 and a welding fixing part 600.

[0095] The rotor core 100 includes a plurality of core segments 110.

[0096] The plurality of core segments 110 are stacked.

[0097] Any two adjacent iron core segments 110 are arranged offset in the clockwise or counterclockwise direction.

[0098] The rotor iron core 100 is provided with a shaft hole 120.

[0099] The shaft hole 120 axially penetrates through a plurality of iron core segments 110 of the rotor iron core 100.

[0100] The rotating shaft 200 is inserted into the shaft hole 120.

[0101] The first bearing 300 is sleeved on the rotating shaft 200, and the first bearing 300 is in interference fit with the rotating shaft 200.

[0102] The second bearing 400 is sleeved on the rotating shaft 200, and the rotor iron core 100 is located between the first bearing 300 and the second bearing 400.

[0103] At least one of the first bearing 300 and the second bearing 400 is a four-point contact ball bearing.

[0104] The second bearing 400 and the rotating shaft 200 are in clearance fit.

[0105] The first elastic part 500 is sleeved on the rotating shaft 200, and the first bearing 300 is located between the first elastic part 500 and the rotor iron core 100. The first elastic part 500 is used to apply an axial pre-tightening force to the first bearing 300.

[0106] The end face of the second bearing 400 facing the rotor iron core 100 is connected to the outer peripheral wall of the rotating shaft 200 through a welding fixing part 600.

[0107] An electric power steering motor 10 provided by the present application includes a rotor iron core 100, a rotating shaft 200, a first bearing 300, a second bearing 400, a first elastic part 500, and a welding fixing part 600.

[0108] The rotor iron core 100 includes a plurality of iron core segments 110 stacked axially along the rotor iron core 100. Among them, any two adjacent iron core segments 110 are arranged offset in the clockwise direction, or any two adjacent iron core segments 110 are arranged offset in the counterclockwise direction. That is, any two adjacent iron core segments 110 are arranged offset in the circumferential direction of the rotor iron core 100 to form a rotor skew pole. The segmented modular setting of the rotor iron core 100 has the advantages of being convenient for installation and maintenance, and skew poles can be formed between the plurality of iron core segments 110.

[0109] Defining that any two adjacent iron core segments 110 are arranged staggeredly in the clockwise or counterclockwise direction can reduce the cogging torque and torque ripple, thereby reducing electromagnetic vibration. That is to say, by dividing the rotor iron core 100 into multiple iron core segments 110 and making any two adjacent iron core segments 110 arranged staggeredly in the clockwise or counterclockwise direction, the specific harmonic content in the electric power steering motor 10 can be effectively suppressed, the torque ripple and cogging torque of the electric power steering motor 10 can be improved, and thus the vibration and noise of the electric power steering motor 10 can be reduced.

[0110] Furthermore, the rotor iron core 100 is provided with a shaft hole 120. The shaft hole 120 axially penetrates through multiple iron core segments 110 along the rotor iron core 100. A rotating shaft 200 is inserted into the shaft hole 120. A first bearing 300 is sleeved on the rotating shaft 200, and a second bearing 400 is sleeved on the rotating shaft 200. The first bearing 300 is located outside the rotor iron core 100, and the second bearing 400 is located outside the rotor iron core 100. Among them, at least one of the first bearing 300 and the second bearing 400 is a four-point contact ball bearing. That is, the first bearing 300 is a four-point contact ball bearing, and / or the second bearing 400 is a four-point contact ball bearing.

[0111] The four-point contact ball bearing can enhance the overall anti-deformation ability of the electric power steering motor 10, is beneficial to improving the structural stiffness of the electric power steering motor 10, and can reduce the axial displacement amount during the operation of the electric power steering motor 10. In this way, the vibration performance during the operation of the electric power steering motor 10 is further improved, the vibration and noise of the electric power steering motor 10 can be further reduced, and the service performance and market competitiveness of the electric power steering motor 10 are greatly improved.

[0112] Optionally, when both the first bearing 300 and the second bearing 400 are four-point contact ball bearings, that is, four-point contact ball bearings are arranged on both axial sides of the rotor iron core 100. In this way, the matching area and matching angle between the first bearing 300, the second bearing 400 and the rotating shaft 200 are increased, the overall anti-deformation ability of the motor can be further enhanced, the structural stiffness of the electric power steering motor 10 can be further improved, and the axial displacement amount during the operation of the electric power steering motor 10 can be reduced. In this way, the vibration performance during the operation of the electric power steering motor 10 is further improved, and the vibration and noise of the electric power steering motor 10 can be further reduced.

[0113] Among them, after the motor is assembled, the first bearing 300 is located between the first elastic part 500 and the rotor iron core 100. By squeezing the first elastic part 500, the first elastic part 500 applies an axial pre-tightening force to the first bearing 300 to ensure the structural stiffness of the electric power steering motor 10 and is beneficial to reducing the axial displacement amount during the operation of the electric power steering motor 10.

[0114] Among them, the second bearing 400 is in clearance fit with the rotating shaft 200, and the end face of the second bearing 400 facing the rotor core 100 is connected to the outer peripheral wall of the rotating shaft 200 through a welding fixing portion 600. That is to say, the welding fixing portion 600 stably assembles the second bearing 400 and the rotating shaft 200 together.

[0115] The welding fixing portion 600 cooperates with the rotating shaft 200 to limit the second bearing 400 axially, radially, and circumferentially along the rotating shaft 200. To improve the structural stiffness of the electric power steering motor 10, the axial movement amount during the operation of the electric power steering motor 10 can be reduced, and the overall anti-deformation ability of the electric power steering motor 10 can be enhanced. In this way, the vibration performance during the operation of the electric power steering motor 10 is further improved, the vibration noise of the electric power steering motor 10 can be further reduced, and the service performance and market competitiveness of the electric power steering motor 10 are greatly improved.

[0116] In addition, the second bearing 400 is in clearance fit with the rotating shaft 200, and the welding fixing portion 600 stably assembles the second bearing 400 and the rotating shaft 200. This setting can reduce the influence on the radial clearance of the second bearing 400 and ensure the radial clearance of the second bearing 400. In this way, it is beneficial to reduce the frictional torque during the operation of the electric power steering motor 10. That is to say, this setting takes into account reducing the vibration noise of the electric power steering motor 10 and reducing the frictional torque of the electric power steering motor 10, and improves the service performance and market competitiveness of the product.

[0117] Optionally, the first elastic portion 500 includes a wave washer, a spring, a torsion spring, a tension spring, etc., which are not listed one by one here.

[0118] It can be understood that when there is no load, the inner ring of the second bearing 400 is fixed, and the displacement amount of the outer ring of the second bearing 400 relative to the fixed inner ring from one extreme position to another extreme position along the radial direction of the rotor core 100 is denoted as the radial clearance of the second bearing 400.

[0119] It can be understood that when there is no load, the inner ring of the first bearing 300 is fixed, and the displacement amount of the outer ring of the first bearing 300 relative to the fixed inner ring from one extreme position to another extreme position along the axial direction of the rotor core 100 is denoted as the axial clearance of the first bearing 300. Or, when there is no load, the outer ring of the first bearing 300 is fixed, and the displacement amount of the inner ring of the first bearing 300 relative to the fixed outer ring from one extreme position to another extreme position along the axial direction of the rotor core 100 is denoted as the axial clearance of the first bearing 300.

[0120] In some embodiments, optionally, when one of the first bearing 300 and the second bearing 400 is a four-point contact ball bearing, the second bearing 400 is a four-point contact ball bearing.

[0121] In this embodiment, the structures of the first bearing 300 and the second bearing 400 are further defined.

[0122] So that when one of the first bearing 300 and the second bearing 400 is a four-point contact ball bearing, the second bearing 400 is a four-point contact ball bearing, and the first bearing 300 is a non-four-point contact ball bearing.

[0123] In some embodiments, optionally, the welding fixing portion 600 is arranged around the rotating shaft 200.

[0124] In this embodiment, the setting position of the welding fixing portion 600 is further defined.

[0125] Optionally, the welding fixing portion 600 is arranged around the rotating shaft 200, that is, the welding fixing portion 600 is of an annular structure, and along the circumferential direction of the rotating shaft 200, the welding fixing portion 600 is welded around the connection between the rotating shaft 200 and the second bearing 400. That is, circumferential full welding of the rotating shaft 200 and the second bearing 400 is achieved. This setting can increase the mating area and mating angle between the welding fixing portion 600 and the rotating shaft 200 and the second bearing 400, which is beneficial to improving the stability and reliability of the assembly of the rotating shaft 200 and the second bearing 400, so as to enhance the overall anti-deformation ability of the electric power steering motor 10 and reduce the frictional torque of the electric power steering motor 10.

[0126] In some embodiments, optionally, as Figure 3 shown, the number of the welding fixing portions 600 is multiple.

[0127] The multiple welding fixing portions 600 are arranged at intervals along the circumferential direction of the rotating shaft 200.

[0128] In this embodiment, the setting position of the welding fixing portion 600 is further defined.

[0129] Optionally, the number of the welding fixing portions 600 is multiple, and the multiple welding fixing portions 600 are arranged at intervals along the circumferential direction of the rotating shaft 200. This setting can effectively fix the rotating shaft 200 and the second bearing 400 from multiple directions and multiple angles, can ensure the balance and consistency of the forces at different positions of the second bearing 400, can ensure the radial clearance of the second bearing 400, can enhance the overall anti-deformation ability of the electric power steering motor 10, and can reduce the frictional torque of the electric power steering motor 10. And this setting is beneficial to reducing the deformation amount at the connection between the rotating shaft 200 and the second bearing 400, is beneficial to reducing the process difficulty of connecting the rotating shaft 200 and the second bearing 400, and is beneficial to improving the assembly efficiency of the motor.

[0130] In some embodiments, optionally, as Figure 7 shown, the electric power steering motor 10 further includes a housing 700.

[0131] The housing 700 is provided with a first bearing cavity 710 and a second bearing cavity 720 therein.

[0132] The rotor core 100, the rotating shaft 200, the first bearing 300, the second bearing 400, and the first elastic part 500 are all arranged in the housing 700.

[0133] The first bearing 300 is located in the first bearing cavity 710.

[0134] The second bearing 400 is located in the second bearing cavity 720.

[0135] The first elastic part 500 abuts between the side of the first bearing 300 facing away from the rotor core 100 and the cavity wall of the first bearing cavity 710.

[0136] In this embodiment, the electric power steering motor 10 further includes a housing 700.

[0137] The rotor core 100, the rotating shaft 200, the first bearing 300, the second bearing 400, and the first elastic part 500 are all arranged in the housing 700. That is to say, the housing 700 serves as the installation carrier for the rotor core 100, the rotating shaft 200, the first bearing 300, the second bearing 400, and the first elastic part 500, and has the function of installing and fixing the rotor core 100, the rotating shaft 200, the first bearing 300, the second bearing 400, and the first elastic part 500 to ensure the mating dimensions of the rotor core 100, the rotating shaft 200, the first bearing 300, the second bearing 400, and the first elastic part 500.

[0138] The housing 700 is provided with a first bearing cavity 710 and a second bearing cavity 720. The first bearing cavity 710 is used for installing the first bearing 300, and the second bearing cavity 720 is used for installing the second bearing 400.

[0139] The first bearing 300 is in interference fit with the rotating shaft 200. The first elastic part 500 is arranged in the first bearing cavity 710. The first bearing 300 is located between the first elastic part 500 and the rotor core 100. The first elastic part 500 abuts against the first bearing 300, and the first elastic part 500 abuts against the cavity wall of the first bearing cavity 710. That is to say, the first elastic part 500 abuts between the side of the first bearing 300 facing away from the rotor core 100 and the cavity wall of the first bearing cavity 710. The first elastic part 500 is used to apply an axial pre-tightening force to the first bearing 300 so that the first bearing 300 is stably assembled on the rotating shaft 200.

[0140] It can be understood that after the motor is assembled, the first elastic part 500 is located between the first bearing 300 and the cavity wall of the first bearing cavity 710. By squeezing the first elastic part 500, an axial pre-tightening force is applied to the first bearing 300 by the first elastic part 500 to ensure the structural stiffness of the electric power steering motor 10 and is beneficial to reducing the axial movement amount of the electric power steering motor 10 during operation.

[0141] It can be understood that the cavity wall of the first bearing cavity 710 functions to limit the first bearing 300. Specifically, the cavity wall of the first bearing cavity 710 is used to radially limit the first bearing 300 on the rotating shaft 200.

[0142] In addition, the first bearing 300 and the rotating shaft 200 are in interference fit to axially and radially limit the first bearing 300 on the rotating shaft 200.

[0143] In some embodiments, optionally, as Figure 7 shown, a clamping groove 730 is further provided in the housing 700.

[0144] The clamping groove 730 is located on the side of the second bearing cavity 720 facing the first bearing cavity 710, and the clamping groove 730 communicates with the second bearing cavity 720.

[0145] The electric power steering motor 10 further includes a second elastic part 800.

[0146] The second elastic part 800 is arranged in the clamping groove 730.

[0147] The second elastic part 800 is arranged around the rotating shaft 200, and the second elastic part 800 abuts against the second bearing 400. The second elastic part 800 is used to limit the axial displacement of the second bearing 400.

[0148] In this embodiment, a clamping groove 730 is further provided in the housing 700.

[0149] The clamping groove 730 is located on the side of the second bearing cavity 720 facing the first bearing cavity 710, and the clamping groove 730 communicates with the second bearing cavity 720.

[0150] The electric power steering motor 10 further includes a second elastic part 800. The clamping groove 730 is used to install and fix the second elastic part 800. The second elastic part 800 is arranged in the clamping groove 730. The second elastic part 800 is arranged around the rotating shaft 200, and the second elastic part 800 abuts against the second bearing 400. The second elastic part 800 is used to axially limit the second bearing 400 along the rotating shaft 200 to ensure the matching dimensions of the second bearing 400 and the rotating shaft 200. It is beneficial to improve the stability and reliability of the assembly of the rotating shaft 200 and the second bearing 400, enhance the overall anti-deformation ability of the electric power steering motor 10, and reduce the frictional torque of the electric power steering motor 10.

[0151] The welding fixing part 600 and the second elastic part 800 cooperate to ensure the radial clearance of the second bearing 400 while reducing the vibration and noise of the electric power steering motor 10, which can enhance the anti-deformation ability of the motor and reduce the frictional torque of the electric power steering motor 10. That is to say, this setting takes into account reducing the vibration and noise of the electric power steering motor 10 and reducing the frictional torque of the electric power steering motor 10, improving the performance and market competitiveness of the product.

[0152] Optionally, the second elastic part 800 includes springs, torsion springs, tension springs, etc., which will not be listed one by one here.

[0153] In some embodiments, optionally, along the axial direction of the rotating shaft 200, the width of the card slot 730 is smaller than the width of the second elastic part 800.

[0154] In this embodiment, the matching structure of the card slot 730 and the second elastic part 800 is further defined.

[0155] Specifically, along the axial direction of the rotating shaft 200, the width of the card slot 730 is smaller than the width of the second elastic part 800. The second elastic part 800 is in interference fit with the card slot 730, and the second elastic part 800 is extruded, and the second elastic part 800 deforms by self-clamping to effectively limit the displacement of the second bearing 400 in the axial direction of the rotating shaft 200.

[0156] In some embodiments, optionally, as Figure 8 shown, a convex part 722 is provided in the second bearing cavity 720, and the convex part 722 abuts against the outer peripheral wall of the second bearing 400.

[0157] In this embodiment, the matching structure of the housing 700 and the second bearing 400 is further defined.

[0158] Specifically, a convex part 722 is provided in the second bearing cavity 720, and the convex part 722 abuts against the outer peripheral wall of the second bearing 400. Specifically, the convex part 722 is riveted on the outside of the second bearing 400, and the second bearing 400 is welded to the rotating shaft 200. The convex part 722 and the welding fixing part 600 cooperate to limit the second bearing 400 in the axial, radial and circumferential directions of the rotating shaft 200. To improve the structural stiffness of the electric power steering motor 10, the axial runout amount during the operation of the electric power steering motor 10 can be reduced, and the overall anti-deformation ability of the electric power steering motor 10 can be enhanced. In this way, the vibration performance during the operation of the electric power steering motor 10 is further improved, the vibration and noise of the electric power steering motor 10 can be further reduced, and the performance and market competitiveness of the electric power steering motor 10 are greatly improved.

[0159] Optionally, the number of the convex parts 722 is multiple, and the multiple convex parts 722 are arranged at intervals along the circumferential direction of the rotating shaft 200.

[0160] Optionally, the number of the convex portions 722 is one.

[0161] In some embodiments, optionally, as Figure 2 and Figure 6 shown, the rotor core 100 is further provided with a plurality of magnet slots 130.

[0162] The plurality of magnet slots 130 are arranged at intervals along the circumferential direction of the rotating shaft 200, and the magnet slots 130 are located between the shaft hole 120 and the outer peripheral wall of the rotor core 100.

[0163] The electric power steering motor 10 further includes a plurality of permanent magnets 900.

[0164] Each permanent magnet 900 is disposed in one magnet slot 130.

[0165] In this embodiment, the specific structure of the electric power steering motor 10 is further defined.

[0166] A portion of the rotor core 100 located between the shaft hole 120 and the outer peripheral wall of the rotor core 100 is provided with a plurality of magnet slots 130, and the plurality of magnet slots 130 are arranged at intervals along the circumferential direction of the rotating shaft 200.

[0167] The electric power steering motor 10 further includes a plurality of permanent magnets 900, and each permanent magnet 900 is disposed in one magnet slot 130. That is, the plurality of permanent magnets 900 are disposed on the rotor core 100, and the plurality of permanent magnets 900 are arranged at intervals along the circumferential direction of the rotating shaft 200. The permanent magnets 900 are located between the shaft hole 120 and the outer peripheral wall of the rotor core 100.

[0168] In some embodiments, optionally, along the axial direction of the rotating shaft 200, the length of the permanent magnet 900 is less than or equal to the length of the iron core section 110.

[0169] In this embodiment, the mating structure of the rotor core 100 and the permanent magnet 900 is further defined.

[0170] Specifically, along the axial direction of the rotating shaft 200, the length of the permanent magnet 900 is less than or equal to the length of the iron core section 110.

[0171] The iron core section 110 has the function of protecting the permanent magnet 900. In this way, the probability of squeezing the permanent magnet 900 and thus causing damage to the permanent magnet 900 can be reduced.

[0172] If along the axial direction of the rotating shaft 200, the length of the permanent magnet 900 is greater than the length of the iron core section 110, then a part of the permanent magnet 900 is likely to protrude from the iron core section 110. This setting is likely to cause the permanent magnet 900 to be squeezed and damaged, and the service performance of the motor cannot be guaranteed.

[0173] In some embodiments, optionally, as Figure 2 and Figure 6 shown, the rotor core 100 is further provided with a plurality of weight-reducing holes 140.

[0174] The plurality of weight-reducing holes 140 are arranged at intervals along the circumferential direction of the rotating shaft 200.

[0175] The weight-reducing holes 140 are located between the rotating shaft 200 and the permanent magnet 900.

[0176] The number of the weight-reducing holes 140 is greater than or equal to the number of pole pairs of the electric power steering motor 10.

[0177] In this embodiment, the structure of the rotor core 100 is further defined such that the rotor core 100 is provided with a plurality of weight-reducing holes 140, the plurality of weight-reducing holes 140 are arranged at intervals along the circumferential direction of the rotating shaft 200, and the weight-reducing holes 140 are located between the rotating shaft 200 and the permanent magnet 900. The weight-reducing holes 140 function to reduce the overall weight of the motor.

[0178] In addition, any two adjacent iron core segments 110 are arranged in a staggered manner in the clockwise direction or the counterclockwise direction, that is, any two adjacent iron core segments 110 are arranged in a staggered manner in the circumferential direction of the rotor core 100 to form a skewed pole of the rotor. The weight-reducing holes 140 can be used as a positioning basis to assemble the rotor core 100, providing a reliable structural support for ensuring the formation of the skewed pole of the rotor.

[0179] Furthermore, the number of the weight-reducing holes 140 is greater than or equal to the number of pole pairs of the electric power steering motor 10, and the plurality of weight-reducing holes 140 are arranged at intervals along the circumferential direction of the rotating shaft 200. In this way, when assembling the rotor core 100, the plurality of iron core segments 110 can be positioned from multiple directions and multiple angles, and the matching accuracy of the plurality of iron core segments 110 can be ensured.

[0180] Optionally, the number of the weight-reducing holes 140 is equal to the number of pole pairs of the electric power steering motor 10.

[0181] Optionally, the weight-reducing holes 140 are provided on the magnetic pole center line and / or the inter-pole center line of the rotor core 100. To reduce the moment of inertia and the overall weight of the electric power steering motor 10 while ensuring that the use performance of the electric power steering motor 10 is not affected.

[0182] In some embodiments, optionally, at least a part of the hole wall of the shaft hole 120 is in interference fit with the rotating shaft 200.

[0183] In this embodiment, the matching structure of the rotor core 100 and the rotating shaft 200 is defined.

[0184] At least a part of the hole wall of the shaft hole 120 is in interference fit with the rotating shaft 200. That is, a part of the hole wall of the shaft hole 120 is in interference fit with the rotating shaft 200. Or the entire hole wall of the shaft hole 120 is in interference fit with the rotating shaft 200.

[0185] This setting can ensure the mating structure between the rotating shaft 200 and the rotor core 100, and avoid the separation of the rotating shaft 200 and the rotor core 100.

[0186] When a part of the hole wall of the shaft hole 120 is in interference fit with the rotating shaft 200, the contact area between the shaft hole 120 and the rotating shaft 200 can be reduced. That is, while ensuring the use requirement of the interference fit between the rotating shaft 200 and the shaft hole 120, the radial force formed by the interference fit between the rotating shaft 200 and the shaft hole 120 can be reduced due to the reduction of the contact area between the shaft hole 120 and the rotating shaft 200. This can reduce the influence of the radial force on the bonding force between the laminations of the rotor core 100, which is beneficial to reducing the probability of deformation of the laminations of the rotor core 100, and can further reduce the probability of loosening of the multiple laminations of the rotor core 100.

[0187] Optionally, the hole wall of the shaft hole 120 is a concave-convex wall. The protrusions of the concave-convex wall are in interference fit with the rotating shaft 200, and the depressions of the concave-convex wall are arranged separately from the rotating shaft 200. The protrusions and depressions of the concave-convex wall are arranged alternately, and both the protrusions and depressions extend along the axial direction of the rotating shaft 200.

[0188] In some embodiments, optionally, the axial clearance of the second bearing 400 is less than or equal to 0.1 mm.

[0189] In this embodiment, the value range of the axial clearance σ of the second bearing 400 is further limited, such that σ ≤ 0.1 mm. In this way, the axial vibration of the electric power steering motor 10 can be further optimized, so as to further optimize the vibration noise of the electric power steering motor 10.

[0190] It can be understood that when there is no load, the inner ring of the second bearing 400 is fixed, and the displacement of the outer ring of the second bearing 400 relative to the fixed inner ring from one extreme position to another extreme position along the axial direction of the rotor core 100 is denoted as the axial clearance σ of the second bearing 400.

[0191] Optionally, σ = 0.01 mm, σ = 0.02 mm, σ = 0.03 mm, σ = 0.04 mm, σ = 0.05 mm, σ = 0.06 mm, σ = 0.07 mm, σ = 0.08 mm, and σ = 0.09 mm, etc. These are not listed one by one here.

[0192] According to an electric power steering system according to some other embodiments of the present application, it includes: an electric power steering motor 10 as in any of the above embodiments.

[0193] An electric power steering system provided by the present application includes the electric power steering motor 10 as described in any of the above embodiments. Therefore, it has all the beneficial effects of the above electric power steering motor 10, and will not be elaborated one by one here.

[0194] A vehicle according to some further embodiments of the present application includes: the electric power steering motor 10 as described in any of the above embodiments; or the electric power steering system as described in the above embodiments.

[0195] A vehicle provided by the present application includes the electric power steering motor 10 as described in any of the above embodiments, or includes the electric power steering system as described in the above embodiments. Therefore, it has all the beneficial effects of the above electric power steering motor 10 or the electric power steering system, and will not be elaborated one by one here.

[0196] It should be noted that the vehicle can be a new energy vehicle. New energy vehicles include pure electric vehicles, range-extended electric vehicles, hybrid vehicles, fuel cell electric vehicles, hydrogen engine vehicles, etc.

[0197] The vehicle can also be a fuel vehicle and a hybrid vehicle.

[0198] Optionally, the electric power steering motor 10 includes a rotor core 100, a rotating shaft 200, a first bearing 300, a second bearing 400, and a first elastic part 500. At least one of the first bearing 300 and the second bearing 400 is a four-point contact ball bearing, which can enhance the overall anti-deformation ability of the motor, is beneficial to improving the structural stiffness of the motor, can reduce the axial runout amount during the operation of the motor. In this way, the vibration performance during the operation of the motor is further improved, the vibration noise of the motor can be further reduced, and the service performance and market competitiveness of the motor are greatly improved.

[0199] Optionally, the rotor core 100 includes a plurality of core segments 110. The plurality of core segments 110 are stacked, and any two adjacent core segments 110 are arranged offset in the clockwise or counterclockwise direction. The rotor core 100 is provided with a shaft hole 120, and the shaft hole 120 axially penetrates through the plurality of core segments 110 along the rotor core 100.

[0200] The rotating shaft 200 is inserted into the shaft hole 120.

[0201] Optionally, the first elastic part 500 is sleeved on the rotating shaft 200. The first bearing 300 is located between the first elastic part 500 and the rotor core 100. The first elastic part 500 is used to apply an axial pre-tightening force to the first bearing 300, and the first bearing 300 is in interference fit with the rotating shaft 200.

[0202] The second bearing 400 is fixed in the second bearing cavity 720 by riveting through the convex portion 722. The end face of the second bearing 400 facing the rotor core 100 is connected to the outer peripheral wall of the rotating shaft 200 through the welding fixing portion 600.

[0203] Optionally, the welding method can be full welding along the inner edge of the second bearing 400 (that is, the welding fixing portion 600 is arranged around the rotating shaft 200).

[0204] Optionally, the welding method can also be spot welding, and a plurality of spot welding points are arranged at intervals along the circumferential direction of the inner edge of the second bearing 400. That is, the number of the welding fixing portions 600 is multiple, and the multiple welding fixing portions 600 are arranged at intervals along the circumferential direction of the rotating shaft 200.

[0205] Optionally, the electric power steering motor 10 further includes a plurality of permanent magnets 900, and the plurality of permanent magnets 900 are arranged at intervals along the circumferential direction of the shaft hole 120. Along the axial direction of the rotor core 100, the length of the permanent magnet 900 is less than or equal to the length of the iron core segment 110.

[0206] Optionally, the rotor core 100 is provided with a plurality of weight-reducing holes 140, and the plurality of weight-reducing holes 140 are arranged at intervals around the circumferential direction of the rotating shaft 200, and the number of the weight-reducing holes 140 is greater than or equal to the number of pole pairs of the motor.

[0207] Optionally, at least a part of the hole wall of the shaft hole 120 is in interference fit with the rotating shaft 200.

[0208] Optionally, the axial clearance of the second bearing 400 is less than or equal to 0.1 mm.

[0209] Optionally, the motor provided in this application includes a rotor core 100, a rotating shaft 200, bearings, and an elastic portion.

[0210] The rotor core 100 includes a plurality of iron core segments 110 stacked along the axial direction of the rotor core 100. Among them, any two adjacent iron core segments 110 are arranged staggeredly in the clockwise direction, or any two adjacent iron core segments 110 are arranged staggeredly in the counterclockwise direction. That is, any two adjacent iron core segments 110 are arranged staggeredly in the circumferential direction of the rotor core 100 to form a rotor skewed pole. The segmented modular setting of the rotor core 100 has the advantages of being convenient for installation and maintenance, and skew poles can be formed between the plurality of iron core segments 110.

[0211] Defining that any two adjacent iron core segments 110 are arranged staggeredly in the clockwise or counterclockwise direction can reduce the cogging torque and torque ripple, thereby reducing electromagnetic vibration. That is to say, by dividing the rotor iron core 100 into multiple iron core segments 110 and making any two adjacent iron core segments 110 arranged staggeredly in the clockwise or counterclockwise direction, the specific harmonic content in the motor can be effectively suppressed, the torque ripple and cogging torque of the motor can be improved, and the vibration and noise of the motor can be reduced.

[0212] Furthermore, along the axial direction of the rotor iron core 100, the length of the permanent magnet 900 is less than or equal to the length of the iron core segment 110. The iron core segment 110 has the function of protecting the permanent magnet 900. In this way, the probability of squeezing the permanent magnet 900 and then causing damage to the permanent magnet 900 can be reduced. If along the axial direction of the rotor iron core 100, the length of the permanent magnet 900 is greater than the length of the iron core segment 110, then a part of the permanent magnet 900 is likely to protrude from the iron core segment 110. This setting is likely to cause the permanent magnet 900 to be squeezed and damaged, and the service performance of the motor cannot be guaranteed.

[0213] Furthermore, the rotor iron core 100 is provided with a shaft hole 120. The shaft hole 120 penetrates the iron core group along the axial direction of the rotor iron core 100, and the rotating shaft 200 is inserted into the shaft hole 120. At least one of the first bearing 300 and the second bearing 400 is a four-point contact ball bearing, and the axial clearance of the second bearing 400 is less than or equal to 0.1 mm.

[0214] The four-point contact ball bearing can enhance the overall anti-deformation ability of the motor, is beneficial to improving the structural stiffness of the motor, can reduce the axial movement amount during the operation of the motor. In this way, the vibration performance during the operation of the motor is further improved, the vibration and noise of the motor can be further reduced, and the service performance and market competitiveness of the motor are greatly improved.

[0215] The rotor iron core 100 is in interference fit with the rotating shaft 200, the first bearing 300 is in interference fit with the rotating shaft 200, and the first bearing 300 is in contact with the first elastic part 500. Specifically, the first elastic part 500 is sleeved on the rotating shaft 200, and the first bearing 300 is located between the first elastic part 500 and the rotor iron core 100. The first elastic part 500 is used to apply an axial pre-tightening force to the first bearing 300 so that the first bearing 300 is firmly assembled on the rotating shaft 200. The end face of the second bearing 400 facing the rotor iron core 100 and the rotating shaft 200 are connected by a welding fixing part 600. It can be spot welding, and multiple welding points are arranged at intervals along the circumference of the rotating shaft 200. It can also be welded along the inner edge. It is beneficial to improve the overall structural stiffness of the rotor iron core 100, the rotating shaft 200 and the second bearing 400, and enhance the overall anti-deformation ability of the rotor iron core 100, multiple permanent magnets 900, the rotating shaft 200 and the second bearing 400 to reduce the axial movement amount during the operation of the motor.

[0216] Optionally, as Figure 4 shown, the number of welding fixing parts 600 is eight, and the eight welding fixing parts 600 are arranged at intervals along the circumferential direction of the rotating shaft 200. This setting is beneficial to improving the overall structural stiffness of the rotor core 100, the rotating shaft 200 and the second bearing 400, enhancing the overall anti-deformation ability of the rotor core 100, the plurality of permanent magnets 900, the rotating shaft 200 and the second bearing 400, so as to reduce the axial displacement amount during the operation of the motor.

[0217] The rotor core 100 includes a plurality of core segments 110 stacked axially along the rotor core 100. Among them, any two adjacent core segments 110 are arranged staggeredly in the clockwise direction, or any two adjacent core segments 110 are arranged staggeredly in the counterclockwise direction. That is to say, any two adjacent core segments 110 are arranged staggeredly in the circumferential direction of the rotor core 100 to form a skewed pole of the rotor. The segmented modular setting of the rotor core 100 has the advantages of being convenient for installation and maintenance, and a skewed pole can be formed between the plurality of core segments 110.

[0218] Defining that any two adjacent core segments 110 are arranged staggeredly in the clockwise direction or in the counterclockwise direction can reduce the cogging torque and torque ripple, thereby reducing the electromagnetic vibration. That is to say, by dividing the rotor core 100 into a plurality of core segments 110 and making any two adjacent core segments 110 be arranged staggeredly in the clockwise direction or in the counterclockwise direction, the specific harmonic content in the electric power steering motor 10 can be effectively suppressed, the torque ripple and cogging torque of the electric power steering motor 10 can be improved, and thus the effect of reducing the vibration and noise of the electric power steering motor 10 can be achieved.

[0219] Furthermore, the rotor core 100 is provided with a shaft hole 120. The shaft hole 120 axially penetrates through a plurality of core segments 110 along the rotor core 100. The rotating shaft 200 is inserted into the shaft hole 120. The first bearing 300 is sleeved on the rotating shaft 200, and the second bearing 400 is sleeved on the rotating shaft 200. The first bearing 300 is located outside the rotor core 100, and the second bearing 400 is located outside the rotor core 100. Among them, at least one of the first bearing 300 and the second bearing 400 is a four-point contact ball bearing. That is to say, the first bearing 300 is a four-point contact ball bearing, and / or the second bearing 400 is a four-point contact ball bearing.

[0220] The four-point contact ball bearing can enhance the overall anti-deformation ability of the electric power steering motor 10, is beneficial to improving the structural stiffness of the electric power steering motor 10, and can reduce the axial displacement amount during the operation of the electric power steering motor 10. In this way, the vibration performance during the operation of the electric power steering motor 10 is further improved, the vibration and noise of the electric power steering motor 10 can be further reduced, and the service performance and market competitiveness of the electric power steering motor 10 are greatly improved.

[0221] Optionally, when both the first bearing 300 and the second bearing 400 are four-point contact ball bearings, that is, four-point contact ball bearings are provided on both axial sides of the rotor core 100. In this way, the mating area and mating angle between the first bearing 300, the second bearing 400 and the rotating shaft 200 are increased, which can further enhance the overall anti-deformation ability of the motor, can further improve the structural stiffness of the electric power steering motor 10, can reduce the axial end play of the electric power steering motor 10 during operation. In this way, the vibration performance of the electric power steering motor 10 during operation is further improved, and the vibration noise of the electric power steering motor 10 can be further reduced.

[0222] Among them, after the motor is assembled, the first bearing 300 is located between the first elastic part 500 and the rotor core 100. By squeezing the first elastic part 500, the first elastic part 500 applies an axial pre-tightening force to the first bearing 300 to ensure the structural stiffness of the electric power steering motor 10, which is beneficial to reducing the axial end play of the electric power steering motor 10 during operation.

[0223] Among them, the second bearing 400 is in clearance fit with the rotating shaft 200, and the end face of the second bearing 400 facing the rotor core 100 is connected to the outer peripheral wall of the rotating shaft 200 through a welding fixing part 600. That is, the welding fixing part 600 firmly assembles the second bearing 400 and the rotating shaft 200 together.

[0224] The welding fixing part 600 and the rotating shaft 200 cooperate to limit the second bearing 400 axially, radially and circumferentially along the rotating shaft 200. To improve the structural stiffness of the electric power steering motor 10, the axial end play of the electric power steering motor 10 during operation can be reduced, and the overall anti-deformation ability of the electric power steering motor 10 can be enhanced. In this way, the vibration performance of the electric power steering motor 10 during operation is further improved, the vibration noise of the electric power steering motor 10 can be further reduced, and the service performance and market competitiveness of the electric power steering motor 10 are greatly improved.

[0225] In addition, the second bearing 400 is in clearance fit with the rotating shaft 200, and the welding fixing part 600 firmly assembles the second bearing 400 and the rotating shaft 200. This setting can reduce the influence on the radial clearance of the second bearing 400 and ensure the radial clearance of the second bearing 400. In this way, it is beneficial to reduce the frictional torque of the electric power steering motor 10 during operation. That is to say, this setting takes into account reducing the vibration noise of the electric power steering motor 10 and reducing the frictional torque of the electric power steering motor 10, and improves the service performance and market competitiveness of the product.

[0226] In this application, the term "a plurality of" means two or more, unless otherwise clearly defined. Terms such as "installed", "connected", "joined", "fixed", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "joined" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0227] In the description of this specification, the descriptions of terms such as "one embodiment", "some embodiments", "specific embodiments", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of this application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or instance. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. The above are only the preferred embodiments of this application and are not used to limit this application. For those skilled in the art, this application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included in the protection scope of this application.

Claims

1. An electric power steering motor, characterized in that: include: A rotor core, the rotor core comprising a plurality of core segments, the plurality of core segments being stacked, any two adjacent core segments being staggered in a clockwise direction or in a counterclockwise direction, the rotor core being provided with an axial hole, the axial hole penetrating the plurality of core segments in the axial direction of the rotor core; A rotating shaft, passing through the shaft hole; A first bearing, sleeved on the rotating shaft, and the first bearing and the rotating shaft are interference fit; A second bearing is sleeved on the rotating shaft, the rotor core is located between the first bearing and the second bearing, at least one of the first bearing and the second bearing is a four-point contact ball bearing, and the second bearing and the rotating shaft are clearance-matched; a first elastic portion, sleeved on the rotating shaft, wherein the first bearing is located between the first elastic portion and the rotor core, and the first elastic portion is used to apply an axial preload force to the first bearing; The end surface of the second bearing facing the rotor core is connected to the outer peripheral wall of the rotating shaft through a welding fixing portion.

2. The electric power steering motor according to claim 1, characterized in that: When one of the first bearing and the second bearing is a four-point contact ball bearing, the second bearing is a four-point contact ball bearing.

3. The electric power steering motor according to claim 1 or 2, characterized in that: The welding fixing portion is arranged around the rotating shaft.

4. The electric power steering motor according to claim 1 or 2, characterized in that: There are multiple welding fixing parts, and the multiple welding fixing parts are arranged at intervals along the circumferential direction of the rotating shaft.

5. The electric power steering motor according to claim 1 or 2, characterized in that: Also includes: A housing, wherein a first bearing cavity and a second bearing cavity are provided in the housing; The rotor core, the rotating shaft, the first bearing, the second bearing and the first elastic part are all arranged in the housing, the first bearing is located in the first bearing cavity, and the second bearing is located in the second bearing cavity; The first elastic portion abuts between a side of the first bearing facing away from the rotor core and a cavity wall of the first bearing cavity.

6. The electric power steering motor according to claim 5, characterized in that: A slot is also provided in the housing, the slot is located on a side of the second bearing cavity facing the first bearing cavity, and the slot is communicated with the second bearing cavity; The electric power steering motor also includes a second elastic portion, which is disposed in the slot, is disposed around the rotating shaft, and is in contact with the second bearing, and is used to limit the axial displacement of the second bearing.

7. The electric power steering motor according to claim 6, characterized in that: Along the axial direction of the rotating shaft, the width of the clamping groove is smaller than the width of the second elastic portion.

8. The electric power steering motor according to claim 5, characterized in that: A convex portion is provided in the second bearing cavity, and the convex portion abuts against the outer peripheral wall of the second bearing.

9. The electric power steering motor according to claim 1 or 2, characterized in that: The rotor core is further provided with a plurality of magnet slots, which are arranged at intervals along the circumferential direction of the rotating shaft, and the magnet slots are located between the shaft hole and the outer peripheral wall of the rotor core; The electric power steering motor further includes a plurality of permanent magnets, each of which is disposed in one of the magnet slots.

10. The electric power steering motor according to claim 9, characterized in that: Along the axial direction of the rotating shaft, the length of the permanent magnet is less than or equal to the length of the core segment.

11. The electric power steering motor according to claim 9, characterized in that: The rotor core is further provided with a plurality of weight-reducing holes, which are arranged at intervals along the circumference of the rotating shaft, and the weight-reducing holes are located between the rotating shaft and the permanent magnets; The number of the weight-reducing holes is greater than or equal to the number of pole pairs of the electric power steering motor.

12. The electric power steering motor according to claim 1 or 2, characterized in that: At least a portion of the hole wall of the shaft hole is interference fit with the rotating shaft.

13. The electric power steering motor according to claim 1 or 2, characterized in that: The axial clearance of the second bearing is less than or equal to 0.1 mm.

14. An electric power steering system, characterized in that: include: An electric power steering motor as claimed in any one of claims 1 to 13.

15. A vehicle, characterized in that: include: The electric power steering motor according to any one of claims 1 to 13; or The electric power steering system as claimed in claim 14.

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