Electric motor, electric power steering system and vehicle

Abstract

The application provides an electric machine, an electric power steering system and a vehicle. The electric machine comprises a stator core, a rotor core, a rotating shaft and a magnetic part. The stator core is provided with a rotor cavity. The rotor core is located in the rotor cavity and can rotate relative to the stator core. The rotor core is provided with an axial shaft hole. A part of the rotating shaft extends into the shaft hole and cooperates with the rotor core. The magnetic part is arranged on the rotating shaft and located on the shaft side of the rotor core. The radius R1 of the rotor core, the outer radius R2 of the stator core, the axial height L1 of the rotor core and the distance L2 between the rotor core and the magnetic part satisfy 0.75 <= (L2*R2) / (L1*R1) <= 1.5. The position of the magnetic part is not interfered by the magnetic field generated by the stator core and the rotor core. The reading accuracy of the position and speed of the rotor core by the magnetic part is ensured. The reliable operation of the electric machine is ensured.

Description

Technical Field

[0001] This application relates to the field of electrical equipment technology, and more specifically, to an electric motor, an electric power steering system, and a vehicle. Background Technology

[0002] Currently, the position and speed signals of the rotor assembly are monitored in motors using magnets. The magnets rotate synchronously with the rotor assembly, and the signals are transmitted to the sensing chip through the magnetic field.

[0003] However, in motor systems, the rotor assembly contains components such as magnets, which generate magnetic field signals that affect the magnetic field of the magnets, leading to a decrease in the accuracy of the magnet signal acquisition or even failure. Similarly, the stator magnetic field generated when current is applied to the stator assembly of the motor will also interfere with the magnets.

[0004] Therefore, to ensure that the magnetic fields generated by the rotor and stator assemblies do not affect the magnet collection accuracy, a sufficient safe distance must be maintained between the magnets and the rotor and stator assemblies. However, considering the miniaturization design and cost control of the motor, the axial length of the motor cannot be made too long. Therefore, how to ensure the magnet collection accuracy while meeting the miniaturization requirements of the motor has become an urgent problem to be solved. Summary of the Invention

[0005] This application aims to address at least one of the technical problems existing in the prior art or related technologies.

[0006] Therefore, the first aspect of this application is to propose an electric motor.

[0007] The second aspect of this application is to propose an electric power steering system.

[0008] The third aspect of this application is to propose a vehicle.

[0009] In view of the above, according to the first aspect of this application, an electric motor is provided, comprising a stator core, a rotor core, a shaft, and a magnetic element. The stator core has a rotor cavity, the rotor core is located in the rotor cavity and is rotatable relative to the stator core, the rotor core has an axially penetrating shaft hole, a portion of the shaft extends into the shaft hole and engages with the rotor core, and the magnetic element is disposed on the shaft and located on the axial side of the rotor core. The radius R1 of the rotor core, the outer radius R2 of the stator core, the axial height L1 of the rotor core, and the distance L2 between the rotor core and the magnetic element satisfy the condition that 0.75 ≤ (L2 × R2) / (L1 × R1) ≤ 1.5.

[0010] The motor provided in this application includes a stator core, a rotor core, a shaft, and a magnetic component. The stator core has an internal rotor cavity that extends axially through the stator core. The rotor core is located within the rotor cavity, and a gap exists between the rotor core and the stator core. This ensures smooth assembly of the rotor core within the stator core and prevents friction between the rotor core and stator core during rotation, ensuring safe operation of the motor. The rotor core has an axially extending shaft hole, and a portion of the shaft is located within this hole, engaging with the stator core. Furthermore, the magnetic component is mounted on the shaft and located on one axial side of the rotor core, meaning it does not contact the rotor core. The shaft serves as the connection between the magnetic component and the rotor core. During motor operation, the magnetic component, shaft, and rotor core rotate synchronously. The magnetic component can collect position and speed signals from the rotor core and shaft. The magnetic component is a permanent magnet. Magnetic components generate a magnetic field, and the rotor core is made of a magnetically conductive material. The appropriate range of distance L2 between the magnetic component and the rotor core can be determined based on the radius of the rotor core, the outer radius of the stator core, and the axial height of the rotor core. When the distance between the magnetic component and the rotor core satisfies the above relationship, the position of the magnetic component will not be disturbed by the magnetic fields generated by the stator and rotor cores. This ensures the accuracy of the magnetic component's readings of parameters such as the position and speed of the rotor core, guaranteeing reliable motor operation. However, if the distance between the magnetic component and the rotor core exceeds the aforementioned range, the overall axial height of the motor will be too high. This is not suitable for the trend of motor miniaturization and will directly increase the cost of the motor.

[0011] When the value of (L2×R2) / (L1×R1) is lower than 0.75, the strong magnetic fields of the stator and rotor cores interfere with the weak magnetic field of the magnetic components. This causes the position sensor located within the magnetic induction range of the magnetic components to fail to correctly read the speed and position signals, potentially leading to serious consequences such as motor runaway and shutdown. If the value of (L2×R2) / (L1×R1) is higher than 0.75, this interference can be avoided. However, the higher the value of (L2×R2) / (L1×R1), the longer the axial length of the motor, and excessively high values ​​significantly increase the motor cost. Therefore, it is preferable to define the value range of (L2×R2) / (L1×R1) within [0.75, 1.5]. Within this range, the relationship between the distance between the rotor core and the magnetic components and the magnetic induction intensity at the magnetic components achieves optimal performance.

[0012] In one possible design, the maximum radius R3 of the magnetic component, the radius R4 of the shaft, and the radius R1 of the rotor core satisfy the condition that R4≤R3≤R1.

[0013] In this design, the radius of the magnetic component is larger than the radius of the rotating shaft but smaller than the radius of the rotor core. This ensures that the size of the magnetic component is appropriate, avoiding the situation where the magnetic component is too small to achieve the purpose of collecting position and speed signals. Furthermore, if the magnetic component is too small, it may cause assembly difficulties and exacerbate assembly deviations.

[0014] The magnetic component can be directly connected to the rotating shaft, or indirectly connected to the rotating shaft, as long as the two can rotate synchronously.

[0015] In one possible design, the motor further includes a connecting seat, the first end of which is connected to the rotating shaft, and the second end of which is provided with a magnetic element.

[0016] In this design, the shaft and the magnetic component are not directly connected. Instead, they are connected via a connector. The first end of the connector is connected to the shaft, and the second end is used to mount the magnetic component. Since the magnetic component and shaft are expensive, the connector simplifies their structure and allows for better connection between them, thus reducing costs.

[0017] In one possible design, a limiting groove is further provided at one end of the rotating shaft. The connecting seat includes a limiting part and a receiving part, with the limiting part extending into the limiting groove. The receiving part is connected to the limiting part and has a receiving groove in which the magnetic component is located.

[0018] In this design, a limiting groove is provided at one end of the rotating shaft, extending axially with its opening facing away from the rotor core. The connecting seat includes a limiting part and a receiving part. The limiting part is inserted axially into the limiting groove, thereby achieving a reliable connection with the rotating shaft. Furthermore, along a section perpendicular to the axial direction, the cross-section of the limiting groove is neither perfectly circular nor circular. That is, when the limiting part extends into the limiting groove, it can press against the groove wall to form a positional constraint, thereby achieving the purpose of the rotating shaft driving the magnetic components to rotate synchronously through the connecting seat. For example, the limiting part can be a limiting post, and the limiting groove can be an axially extending groove, with the limiting post inserted into the limiting groove for reliable assembly.

[0019] The storage section has a storage groove, in which magnetic components are embedded. The opening of the storage groove is positioned away from the rotor core to facilitate the assembly of the magnetic components.

[0020] In one possible design, the maximum radius R3 of the magnetic component and the maximum radius R5 of the storage part satisfy 0.75≤R3 / R5<1.

[0021] In this design, the ratio between the maximum radius R3 of the magnetic component and the radius R5 of the storage part is within the above range, that is, the magnetic component is slightly smaller than the storage part. This avoids the storage part being too large and the magnetic component being too small, as the storage part may shield the magnetic field generated by the magnetic component, thus affecting the accurate sensing between the magnetic component and the sensing sensor.

[0022] It is worth noting that the magnetic component can also be directly connected to the limiting part, meaning that the connector only includes the limiting part and does not have a storage part, making the structure simpler.

[0023] In one possible design, the storage part further includes a storage tray and a storage rib, with the storage tray connected between the limiting part and the storage rib; wherein the axial height L3 of the storage tray, the maximum axial height L4 of the magnetic component, the radius R6 of the limiting part, and the radius R4 of the rotating shaft satisfy 0.8≤(R6 / R4) / (L3 / L4)≤1.2.

[0024] In this design, the storage section includes a storage tray and storage ribs. The storage tray, which is disc-shaped and has a certain thickness, is connected between the limiting part and the storage ribs. The storage ribs are connected to the storage tray and extend in the direction away from the rotor core. The storage tray and storage ribs together form a storage groove for assembling magnetic components. The radius of the rotating shaft, the radius of the limiting part, the axial height of the storage tray, and the maximum axial height of the magnetic components are interrelated. By ensuring that these four factors satisfy the above-mentioned relationship, the reliable connection performance between the connecting seat and the rotating shaft can be guaranteed. At the same time, it can provide stable and reliable storage for the magnetic components, preventing the connecting seat from detaching from the rotating shaft and the magnetic components from detaching from the connecting seat during high-speed rotation, thus ensuring a reliable connection between the magnetic components, the connecting seat, and the rotating shaft.

[0025] In one possible design, the minimum distance L5 between the storage tray and the pivot satisfies 0.1mm≤L5≤2mm.

[0026] In this design, there is a gap between the storage tray and the rotating shaft. This gap provides a pressing allowance, preventing excessive pressure from pressing the storage tray directly onto the shaft and causing damage. Simultaneously, the gap also helps identify the pressing distance to determine if the connector is properly installed.

[0027] In one possible design, the radius R6 of the limiting part and the radius R4 of the rotating shaft satisfy 0.2≤R6 / R4≤0.3.

[0028] In this design, the radius of the limiting part and the radius of the rotating shaft satisfy the above relationship. Under the premise of ensuring reliable support for the limiting part, it can avoid the excessive volume of the upper limit groove of the rotating shaft from affecting the structural strength of the rotating shaft itself.

[0029] In one possible design, the connector may be a metal or plastic base.

[0030] In this design, the connector is a one-piece structure, meaning the storage section and the limiting section are integrated. Because of the superior mechanical properties of this one-piece structure, the connection strength between the storage section and the limiting section is improved. Furthermore, the storage section and the limiting section can be manufactured as a single piece for mass production, increasing processing efficiency and reducing costs. Moreover, by designing the storage section and the limiting section as a single molded structure, the overall integrity of the connector is improved, the number of parts is reduced, installation steps are simplified, installation efficiency is increased, and the connector is installed more conveniently and reliably.

[0031] Furthermore, the connector can be made of metal, offering high structural strength and excellent wear resistance. Alternatively, the connector can be made of plastic, manufactured using injection molding, resulting in a lightweight structure that helps reduce the overall weight of the motor and is also cost-effective.

[0032] In one possible design, the motor further includes a bearing, which is sleeved on the shaft and located on the axial side of the rotor core. The distance L6 between the bearing and the rotor core, the maximum radius R7 of the bearing, and the radius R1 of the rotor core satisfy the condition 0.45≤(R1-R7)×L6≤3.75.

[0033] In this design, the motor also includes a bearing mounted on the shaft. The distance between the bearing and the rotor core, the axial height of the bearing, the maximum radius of the bearing, and the radius of the rotor core satisfy the aforementioned relationship. This ensures that the rotor core will not experience magnetic leakage due to being too close to the bearing, which would lead to a decrease in the motor's back electromotive force and insufficient torque. Simultaneously, when the above four parameters meet this range requirement, the distance between the bearing and the rotor core will not be excessive, avoiding an increase in the motor's axial dimension and thus preventing increased costs.

[0034] Specifically, when the value of (R1-R7)×L6 is less than this range, due to the axial leakage flux effect, the back electromotive force of the motor decreases as (R1-R7)×L6 decreases, further reducing the output torque of the motor and failing to meet the expected functional requirements. If the value of (R1-R7)×L6 is higher than the minimum value of this range, the leakage flux phenomenon will not occur, but an excessively high value of (R1-R7)×L6 will increase the axial length of the motor, further increasing the motor cost. In summary, preferably, the value range of (R1-R7)×L6 is defined within [0.45, 3.75]. This ensures reliable product operation, effectively reduces motor costs, and improves product competitiveness.

[0035] In one possible design, the bearing further includes a first bearing, and the motor also includes a housing having a receiving cavity in which the stator core and rotor core are housed, and the first bearing is connected to the housing.

[0036] In this design, the bearing includes a first bearing connected to the housing. The housing forms a receiving cavity to properly house the stator core and rotor core, providing good protection for the stator core and rotor core and preventing external environmental interference with the operation of the motor.

[0037] In one possible design, the bearing further includes a second bearing positioned close to the magnetic component relative to the first bearing; the motor also includes an end cover located on one axial side of the rotor core, with an elastic washer positioned between the second bearing and the end cover.

[0038] In this design, the bearing also includes a second bearing, which is positioned close to the magnetic component relative to the first bearing, i.e., the second bearing is located between the magnetic component and the rotor core. The motor also includes an end cover, which is located on one axial side of the rotor core. An elastic washer is provided between the second bearing and the end cover, and the elastic washer can buffer the vibration generated at the second bearing.

[0039] The axial distances between the first bearing, the second bearing, and the rotor core all satisfy the above-mentioned relationship. The axial distance between the first bearing and the rotor core can be equal to or unequal to the axial distance between the second bearing and the rotor core.

[0040] In one possible design, the maximum radius R3 of the magnetic component, the radius R4 of the shaft, the radius R1 of the rotor core, and the maximum radius R7 of the second bearing satisfy the condition that R4≤R3≤R7≤R1.

[0041] In this design, the maximum radius R3 of the magnetic component, the radius R4 of the shaft, the radius R1 of the rotor core, and the maximum radius R7 of the second bearing satisfy the above relationship, so that the relative size relationship of the magnetic component, shaft, rotor core and second bearing satisfies a certain relationship, thereby making the structure layout of the motor more rational and conducive to improving the motor performance.

[0042] According to a second aspect of this application, an electric power steering system is provided, comprising a motor provided by any of the above-described designs.

[0043] The electric power steering system provided in this application includes the motor provided in any of the above designs, and therefore has all the beneficial effects of that motor, which will not be repeated here.

[0044] Electric Power Steering (EPS) is a power steering system that relies directly on an electric motor to provide auxiliary torque. Compared to the traditional Hydraulic Power Steering (HPS) system, EPS has many advantages. EPS mainly consists of a torque sensor, vehicle speed sensor, electric motor, reduction gear, and electronic control unit (ECU).

[0045] According to a third aspect of this application, a vehicle is provided, including an electric motor or electric power steering system provided by any of the above designs.

[0046] The vehicle provided in this application includes the electric motor or electric power steering system provided by any of the above designs, and therefore has all the beneficial effects of the electric motor or electric power steering system, which will not be repeated here.

[0047] The vehicles can be either traditional gasoline-powered vehicles or new energy vehicles. New energy vehicles include pure electric vehicles, range-extended electric vehicles, hybrid electric vehicles, fuel cell electric vehicles, and hydrogen engine vehicles.

[0048] Additional aspects and advantages of this application will become apparent in the following description or may be learned by practice of this application. Attached Figure Description

[0049] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0050] Figure 1 One of the structural schematic diagrams of the motor according to one embodiment of this application is shown;

[0051] Figure 2 A partial structural schematic diagram of a motor according to one embodiment of this application is shown;

[0052] Figure 3 A second schematic diagram of the structure of the motor according to one embodiment of this application is shown;

[0053] Figure 4 A schematic diagram showing the effect of the magnetic field generated by the rotor core on the sensing sensor is shown.

[0054] Figure 5 A schematic diagram showing the relationship between the distance from the rotor core to the magnetic element and the magnetic induction intensity at the magnetic element is shown in one embodiment of this application;

[0055] Figure 6 A schematic diagram showing the relationship between the distance between the bearing and the rotor core and the back electromotive force in one embodiment according to this application is shown;

[0056] Figure 7 A schematic diagram of an electric power steering system according to one embodiment of this application is shown.

[0057] Figure label:

[0058] 100 motor,

[0059] 110 stator core,

[0060] 120 rotor core,

[0061] 130 swivel,

[0062] 140 magnetic components,

[0063] 150 connector,

[0064] 151 Limiting Part

[0065] 152 Storage Unit, 1521 Storage Tray, 1522 Storage Ribs

[0066] 161 First bearing, 162 Second bearing,

[0067] 200 Electric Power Steering System

[0068] 211 Steering wheel, 212 Steering shaft, 213 Universal coupling, 214 Rotary shaft, 215 Rack and pinion mechanism, 216 Rack and pinion shaft, 217 Wheel.

[0069] 221 Steering torque sensor, 222 Control unit, 223 Reduction mechanism. Detailed Implementation

[0070] To better understand the above-mentioned objectives, features, and advantages of this application, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0071] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below.

[0072] The following reference Figures 1 to 7 This application describes a motor 100, an electric power steering system 200, and a vehicle provided according to some embodiments.

[0073] According to an embodiment of the first aspect of this application, such as Figure 1 , Figure 2 and Figure 3As shown, a motor 100 is provided, which includes a stator core 110, a rotor core 120, a rotating shaft 130, and a magnetic element 140. The stator core 110 has a rotor cavity, the rotor core 120 is located in the rotor cavity and can rotate relative to the stator core 110, the rotor core 120 has an axially penetrating shaft hole, a part of the rotating shaft 130 extends into the shaft hole and cooperates with the rotor core 120, and the magnetic element 140 is provided on the rotating shaft 130 and located on one axial side of the rotor core 120. The radius R1 of the rotor core 120, the outer radius R2 of the stator core 110, the axial height L1 of the rotor core 120, and the distance L2 between the rotor core 120 and the magnetic element 140 satisfy the condition 0.75≤(L2×R2) / (L1×R1)≤1.5.

[0074] The motor 100 provided in this application includes a stator core 110, a rotor core 120, a rotating shaft 130, and a magnetic component 140. The stator core 110 has a rotor cavity that extends axially through the stator core 110. The rotor core 120 is located within the rotor cavity, and a gap exists between the rotor core 120 and the stator core 110. This ensures that the rotor core 120 can be smoothly assembled inside the stator core 110, and also ensures that no friction occurs between the rotor core 120 and the stator core 110 when the rotor core 120 rotates relative to the stator core 110, thus ensuring the safe operation of the motor 100. The rotor core 120 has an axially extending shaft hole, and a portion of the rotating shaft 130 is located within the shaft hole, with the rotating shaft 130 engaging with the stator core 110. Furthermore, the magnetic component 140 is mounted on the rotating shaft 130 and is located on one axial side of the rotor core 120, meaning that the magnetic component 140 and the rotor core 120 are not in contact. The rotating shaft 130 serves as the connection structure between the magnetic component 140 and the rotor core 120. During the operation of the motor 100, the magnetic component 140, the rotating shaft 130, and the rotor core 120 rotate synchronously. The magnetic component 140 can collect position signals and speed signals from the rotor core 120 and the rotating shaft 130. The magnetic component 140 is a permanent magnet. The magnetic component 140 can generate a magnetic field, and the rotor core 120 is made of a magnetically conductive material. Based on the radius of the rotor core 120, the outer radius of the stator core 110, and the axial height of the rotor core 120, a reasonable range for the distance L2 between the magnetic component 140 and the rotor core 120 can be determined. When the distance between the magnetic component 140 and the rotor core 120 satisfies the above relationship, it can be ensured that the position of the magnetic component 140 will not be disturbed by the magnetic fields generated by the stator core 110 and the rotor core 120, thus ensuring the accuracy of the magnetic component 140 in reading parameters such as the position and speed of the rotor core 120, and ensuring the reliable operation of the motor 100. However, when the distance between the magnetic component 140 and the rotor core 120 exceeds the aforementioned range, the axial height of the entire motor 100 will be too high. This is not suitable for the miniaturization trend of the motor 100 and will directly increase the cost of the motor 100.

[0075] When the value of (L2×R2) / (L1×R1) is less than 0.75, the strong magnetic fields of the stator core 110 and rotor core 120 will interfere with the weak magnetic field of the magnetic component 140. This will cause the position sensor located within the magnetic induction range of the magnetic component 140 to fail to correctly read the speed and position signals, which may further lead to serious consequences such as the motor 100 losing control and stopping operation. If the value of (L2×R2) / (L1×R1) is greater than 0.75, this interference can be avoided. However, the higher the value of (L2×R2) / (L1×R1), the longer the axial length of the motor 100, and an excessively high value will significantly increase the cost of the motor 100. In summary, preferably, the value range of (L2×R2) / (L1×R1) is defined within [0.75, 1.5]. The relationship between the distance between the rotor core 120 and the magnetic component 140 and the magnetic induction intensity at the magnetic component 140 is as follows: Figure 4 and Figure 5 As shown, optimal performance can be obtained within this range.

[0076] Furthermore, the maximum radius R3 of the magnetic component 140, the radius R4 of the rotating shaft 130, and the radius R1 of the rotor core 120 satisfy the condition that R4≤R3≤R1.

[0077] In this embodiment, the radius of the magnetic component 140 is larger than the radius of the rotating shaft 130 and smaller than the radius of the rotor core 120. This allows the magnetic component 140 to be of a suitable size, avoiding the situation where the magnetic component 140 is too small to achieve the purpose of collecting position and speed signals. Furthermore, if the magnetic component 140 is too small, it may also cause assembly difficulties and aggravate assembly deviations.

[0078] The magnetic component 140 can be directly connected to the rotating shaft 130, or the magnetic component 140 can be indirectly connected to the rotating shaft 130, as long as the two can rotate synchronously.

[0079] Furthermore, such as Figure 1 , Figure 2 and Figure 3 As shown, the motor 100 also includes a connecting seat 150, the first end of which is connected to the rotating shaft 130, and the second end of which is provided with a magnetic element 140.

[0080] In this embodiment, the rotating shaft 130 and the magnetic component 140 are not directly connected. Instead, they are connected via a connecting seat 150. The first end of the connecting seat 150 is connected to the rotating shaft 130, and the second end is used to mount the magnetic component 140. Since the magnetic component 140 and the rotating shaft 130 are relatively expensive, the structure of the magnetic component 140 and the rotating shaft 130 can be simplified by setting the connecting seat 150. The connecting seat 150 can be used to adapt to the connection requirements of the rotating shaft 130 and the magnetic component 140, thereby reducing costs.

[0081] Furthermore, such as Figure 2 and Figure 3 As shown, one end of the rotating shaft 130 is provided with a limiting groove. The connecting seat 150 includes a limiting part 151 and a receiving part 152, with the limiting part 151 extending into the limiting groove. The receiving part 152 is connected to the limiting part 151 and is provided with a receiving groove, in which the magnetic component 140 is disposed.

[0082] In this embodiment, a limiting groove is provided at one end of the rotating shaft 130. The limiting groove extends axially and its opening is positioned away from the rotor core 120. The connecting seat 150 includes a limiting part 151 and a receiving part 152. The limiting part 151 is inserted into the limiting groove axially to achieve a reliable connection with the rotating shaft 130. Furthermore, the cross-section of the limiting groove is neither perfectly circular nor circular along a section perpendicular to the axial direction. That is, when the limiting part 151 extends into the limiting groove, it can press against the groove wall to form a position limit, thereby achieving the purpose of the rotating shaft 130 driving the magnetic component 140 to rotate synchronously through the connecting seat 150. For example, the limiting part 151 can be a limiting post, and the limiting groove can be an axially extending groove. The limiting post can be inserted into the limiting groove to achieve reliable assembly.

[0083] The storage section 152 has a storage groove, and the magnetic component 140 is embedded in the storage groove. The opening of the storage groove is set away from the rotor core 120 to facilitate the assembly of the magnetic component 140.

[0084] Furthermore, such as Figure 1 , Figure 2 and Figure 3 As shown, the maximum radius R3 of the magnetic component 140 and the maximum radius R5 of the storage part 152 satisfy 0.75≤R3 / R5<1.

[0085] In this embodiment, the ratio between the maximum radius R3 of the magnetic component 140 and the radius R5 of the storage portion 152 is within the above range, that is, the magnetic component 140 is slightly smaller than the storage portion 152. This avoids the storage portion 152 being too large and the magnetic component 140 being too small, as the storage portion 152 may shield the magnetic field generated by the magnetic component 140, thus affecting the accurate sensing between the magnetic component 140 and the sensing sensor.

[0086] It is worth noting that the magnetic component 140 can also be directly connected to the limiting part 151, that is, the connecting seat 150 only includes the limiting part 151 and does not have the storage part 152, which makes the structure simpler.

[0087] Furthermore, such as Figure 1 , Figure 2 and Figure 3As shown, the storage part 152 includes a storage tray 1521 and a storage rib 1522. The storage tray 1521 is connected between the limiting part 151 and the storage rib 1522. The axial height L3 of the storage tray 1521, the maximum axial height L4 of the magnetic component 140, the radius R6 of the limiting part 151 and the radius R4 of the rotating shaft 130 satisfy the condition 0.8≤(R6 / R4) / (L3 / L4)≤1.2.

[0088] In this embodiment, the storage portion 152 includes a storage tray 1521 and a storage rib 1522. The storage tray 1521 is connected between the limiting portion 151 and the storage rib 1522. The storage tray 1521 is disc-shaped and has a certain thickness. The storage rib 1522 is connected to the storage tray 1521 and extends in a direction away from the rotor core 120. The storage tray 1521 and the storage rib 1522 together form a storage groove for assembling the magnetic component 140. The radius of the rotating shaft 130, the radius of the limiting part 151, the axial height of the storage tray 1521, and the maximum axial height of the magnetic component 140 are interconnected, and the four satisfy the above-mentioned relationship. This ensures the reliable connection performance between the connecting seat 150 and the rotating shaft 130, and provides stable and reliable storage for the magnetic component 140. It also prevents the connecting seat 150 from detaching from the rotating shaft 130 and the magnetic component 140 from detaching from the connecting seat 150 during high-speed rotation, thus ensuring a reliable connection between the magnetic component 140, the connecting seat 150, and the rotating shaft 130.

[0089] Furthermore, such as Figure 1 , Figure 2 and Figure 3 As shown, the minimum distance L5 between the storage tray 1521 and the rotating shaft 130 satisfies 0.1mm≤L5≤2mm.

[0090] In this embodiment, a gap exists between the storage tray 1521 and the rotating shaft 130. This gap provides a pressing allowance, preventing excessive pressure from pressing the connecting seat 150 onto the rotating shaft 130 and potentially damaging the rotating shaft 130. Simultaneously, the gap also helps identify the pressing distance to determine whether the connecting seat 150 is properly installed.

[0091] Furthermore, such as Figure 1 , Figure 2 and Figure 3 As shown, the radius R6 of the limiting part 151 and the radius R4 of the rotating shaft 130 satisfy 0.2≤R6 / R4≤0.3.

[0092] In this embodiment, the radius of the limiting part 151 and the radius of the rotating shaft 130 satisfy the above relationship. Under the premise of ensuring reliable support for the limiting part 151, the volume of the upper limit groove of the rotating shaft 130 is too large, which may affect the structural strength of the rotating shaft 130 itself.

[0093] Furthermore, the connector 150 can be a metal or plastic base.

[0094] In this embodiment, the connector 150 is a one-piece structure, meaning the storage part 152 and the limiting part 151 are integrated. Because of the superior mechanical properties of a one-piece structure, the connection strength between the storage part 152 and the limiting part 151 is improved. Furthermore, the storage part 152 and the limiting part 151 can be manufactured as a single piece for mass production, thereby improving processing efficiency and reducing processing costs. Moreover, by designing the storage part 152 and the limiting part 151 as a single-piece structure, the overall integrity of the connector 150 is improved, the number of parts is reduced, installation steps are decreased, installation efficiency is improved, and the installation of the connector 150 becomes more convenient and reliable.

[0095] Furthermore, the connector 150 can be made of metal, which provides high structural strength and good wear resistance. Alternatively, the connector 150 can be made of plastic, which can be manufactured using injection molding. This results in a lightweight structure, reducing the overall weight of the motor 100 and lowering costs.

[0096] Furthermore, such as Figure 1 , Figure 3 and Figure 6 As shown, the motor 100 also includes a bearing, which is sleeved on the rotating shaft 130 and located on the axial side of the rotor core 120. The distance L6 between the bearing and the rotor core 120, the maximum radius R7 of the bearing, and the radius R1 of the rotor core 120 satisfy the condition 0.45≤(R1-R7)×L6≤3.75.

[0097] In this embodiment, the motor 100 also includes a bearing sleeved on the rotating shaft 130. The distance between the bearing and the rotor core 120, the axial height of the bearing itself, the maximum radius of the bearing, and the radius of the rotor core 120 satisfy the above-mentioned relationship. This ensures that the rotor core 120 will not experience magnetic leakage due to being too close to the bearing, which would lead to a decrease in the back electromotive force of the motor 100 and insufficient torque. Simultaneously, when the above four parameters meet the required range, it ensures that the distance between the bearing and the rotor core 120 will not be too large, avoiding an increase in the axial dimension of the motor 100 and thus avoiding increased costs.

[0098] Specifically, such as Figure 6As shown, when the value of (R1-R7)×L6 is less than this range, due to the axial leakage flux effect, the back electromotive force of motor 100 decreases as (R1-R7)×L6 decreases, further reducing the output torque of motor 100 and failing to meet the expected functional requirements. If the value of (R1-R7)×L6 is higher than the minimum value of this range, the leakage flux phenomenon will not occur, but an excessively high value of (R1-R7)×L6 will increase the axial length of motor 100, further increasing the cost of motor 100. In summary, preferably, the value range of (R1-R7)×L6 is defined within [0.45, 3.75]. This ensures reliable product operation, effectively reduces the cost of motor 100, and improves product competitiveness.

[0099] Furthermore, such as Figure 1 As shown, the bearing includes a first bearing 161, and the motor 100 also includes a housing with a receiving cavity. The stator core 110 and the rotor core 120 are housed in the receiving cavity, and the first bearing 161 is connected to the housing.

[0100] In this embodiment, the bearing includes a first bearing 161, which is connected to the housing. The housing can form a receiving cavity to properly accommodate the stator core 110 and the rotor core 120, providing good protection for the stator core 110 and the rotor core 120 and preventing external environment from interfering with the operation of the motor 100.

[0101] Furthermore, such as Figure 1 As shown, the bearing also includes a second bearing 162, which is disposed near the magnetic component 140 relative to the first bearing 161; the motor 100 also includes an end cover, which is disposed on one axial side of the rotor core 120, and an elastic washer is provided between the second bearing 162 and the end cover.

[0102] In this embodiment, the bearing further includes a second bearing 162, which is disposed near the magnetic element 140 relative to the first bearing 161, i.e., the second bearing 162 is located between the magnetic element 140 and the rotor core 120. The motor 100 also includes an end cover, which is disposed on one axial side of the rotor core 120. An elastic washer is provided between the second bearing 162 and the end cover, and the elastic washer can buffer the vibration generated at the second bearing 162.

[0103] The axial distances between the first bearing 161, the second bearing 162 and the rotor core 120 all satisfy the above-mentioned relationship. The axial distance between the first bearing 161 and the rotor core 120 can be equal to or unequal to the axial distance between the second bearing 162 and the rotor core 120.

[0104] Furthermore, such as Figure 1As shown, the maximum radius R3 of the magnetic component 140, the radius R4 of the rotating shaft 130, the radius R1 of the rotor core 120, and the maximum radius R7 of the second bearing 162 satisfy the condition that R4≤R3≤R7≤R1.

[0105] In this embodiment, the maximum radius R3 of the magnetic component 140, the radius R4 of the rotating shaft 130, the radius R1 of the rotor core 120, and the maximum radius R7 of the second bearing 162 satisfy the above-mentioned relationship, so that the relative size relationship of the magnetic component 140, the rotating shaft 130, the rotor core 120, and the second bearing 162 satisfies a certain relationship, thereby making the structural layout of the motor 100 more rational and conducive to improving the performance of the motor 100.

[0106] According to an embodiment of the second aspect of this application, such as Figure 7 As shown, an electric power steering system 200 is provided, including a motor 100 provided in any of the above designs.

[0107] The electric power steering system 200 provided in this application includes the motor 100 provided in any of the above designs, and therefore has all the beneficial effects of the motor 100, which will not be repeated here.

[0108] Among them, the Electric Power Steering (EPS) system is a power steering system that directly relies on the motor 100 to provide auxiliary torque. Compared with the traditional hydraulic power steering (HPS) system, the EPS system has a simpler structure, more flexible assembly, saves energy, and protects the environment. Most modern vehicles are equipped with EPS systems.

[0109] The electric power steering system 200 can be implemented in several ways. One such implementation will be described in detail below. Specifically, in one implementation, the EPS system has a steering system and an auxiliary torque mechanism that generates auxiliary torque. The EPS system generates auxiliary torque that assists the steering torque generated by the driver operating the steering wheel. This auxiliary torque reduces the driver's workload.

[0110] The steering system specifically includes a steering wheel 211, a steering shaft 212, a universal coupling 213, a rotating shaft 214, a rack and pinion mechanism 215, a rack and pinion shaft 216, and left and right steering wheels 217, etc.

[0111] The auxiliary torque mechanism specifically includes a steering torque sensor 221, an automotive electronic control unit (ECU) 222, a motor, and a reduction gear 223. Specifically, the steering torque sensor 221 detects the steering torque of the steering system. The control unit 222 generates a drive signal based on the detection signal from the steering torque sensor 221. The motor generates an auxiliary torque corresponding to the steering torque based on the drive signal. The motor transmits the generated auxiliary torque to the steering system via the reduction gear 223.

[0112] According to an embodiment of the third aspect of this application, a vehicle is provided, including a motor 100 or an electric power steering system 200 provided by any of the above designs.

[0113] The vehicle provided in this application includes the motor 100 or electric power steering system 200 provided in any of the above designs, and therefore has all the beneficial effects of the motor 100 or electric power steering system 200, which will not be repeated here.

[0114] The vehicles can be either traditional gasoline-powered vehicles or new energy vehicles. New energy vehicles include pure electric vehicles, range-extended electric vehicles, hybrid electric vehicles, fuel cell electric vehicles, and hydrogen engine vehicles.

[0115] In this application, the term "multiple" refers to two or more unless otherwise expressly defined. The terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linking" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0116] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0117] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An electric motor, characterized in that, include: A stator core, wherein a rotor cavity is provided on the stator core; The rotor core is located inside the rotor cavity and can rotate relative to the stator core. The rotor core is provided with an axially penetrating shaft hole. A rotating shaft, a portion of which extends into the shaft hole and engages with the rotor core; A magnetic component is disposed on the rotating shaft and located on one side of the axial direction of the rotor core; the magnetic component is a permanent magnet. The radius R1 of the rotor core, the outer radius R2 of the stator core, the axial height L1 of the rotor core, and the distance L2 between the rotor core and the magnetic component satisfy the following conditions: 0.75≤(L2×R2) / (L1×R1)≤1.5; The motor also includes: The bearing is sleeved on the rotating shaft and located on the axial side of the rotor core. Wherein, the distance L6 between the bearing and the rotor core, the maximum radius R7 of the bearing, and the radius R1 of the rotor core satisfy the following conditions: 0.45≤(R1-R7)×L6≤3.

75.

2. The motor according to claim 1, characterized in that, The maximum radius R3 of the magnetic component, the radius R4 of the rotating shaft, and the radius R1 of the rotor core satisfy the condition that R4≤R3≤R1.

3. The motor according to claim 1, characterized in that, The motor also includes: A connecting seat, the first end of which is connected to the rotating shaft, and the second end of which is provided with the magnetic element.

4. The motor according to claim 3, characterized in that, One end of the rotating shaft is provided with a limiting groove; The connector includes: A limiting part, wherein the limiting part extends into the limiting groove; The storage part is connected to the limiting part, and the storage part is provided with a storage groove, and the magnetic component is disposed in the storage groove.

5. The motor according to claim 4, characterized in that, The maximum radius R3 of the magnetic component and the maximum radius R5 of the storage part satisfy the condition that 0.75 ≤ R3 / R5 < 1.

6. The motor according to claim 4, characterized in that, The storage section includes a storage tray and storage ribs, wherein the storage tray is connected between the limiting section and the storage ribs; wherein... The axial height L3 of the storage tray, the maximum axial height L4 of the magnetic component, the radius R6 of the limiting part, and the radius R4 of the rotating shaft satisfy the following conditions: 0.8≤(R6 / R4) / (L3 / L4)≤1.

2.

7. The motor according to claim 6, characterized in that, The minimum distance L5 between the storage tray and the rotating shaft satisfies 0.1mm≤L5≤2mm.

8. The motor according to claim 4, characterized in that, The radius R6 of the limiting part and the radius R4 of the rotating shaft satisfy the condition 0.2≤R6 / R4≤0.

3.

9. The motor according to claim 3, characterized in that, The connector can be a metal or plastic base.

10. The motor according to any one of claims 1 to 9, characterized in that, The bearing includes a first bearing; The motor also includes: The housing has a receiving cavity, in which the stator core and the rotor core are housed, and the first bearing is connected to the housing.

11. The motor according to claim 10, characterized in that, The bearing further includes a second bearing, which is disposed relative to the first bearing and close to the magnetic element; The motor also includes: An end cover is provided on one axial side of the rotor core, and an elastic washer is provided between the second bearing and the end cover.

12. The motor according to claim 11, characterized in that, The maximum radius R3 of the magnetic component, the radius R4 of the rotating shaft, the radius R1 of the rotor core, and the maximum radius R7 of the second bearing satisfy the condition that R4≤R3≤R7≤R1.

13. An electric power steering system, characterized in that, include: The motor as described in any one of claims 1 to 12.

14. A vehicle, characterized in that, include: The motor as described in any one of claims 1 to 12, or the electric power steering system as described in claim 13.

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