CN116260260A

CN116260260A - Motor, electric power steering system and vehicle

Info

Publication number: CN116260260A
Application number: CN202111510496.3A
Authority: CN
Inventors: 徐珂; 朱莲莉; 葛笑
Original assignee: Guangdong Welling Auto Parts Co Ltd; Anhui Welling Auto Parts Co Ltd
Current assignee: Guangdong Welling Auto Parts Co Ltd; Anhui Welling Auto Parts Co Ltd
Priority date: 2021-12-10
Filing date: 2021-12-10
Publication date: 2023-06-13
Also published as: WO2023103226A1

Abstract

The application provides a motor, electric power steering system and vehicle, the motor includes stator core, rotor core, pivot and magnetic part, be equipped with the rotor chamber on the stator core, rotor core is located the rotor intracavity and can rotate for the stator core, be equipped with the shaft hole that the axial runs through on the rotor core, a portion of pivot stretches into in the shaft hole and cooperates with the rotor core, the magnetic part is established in the pivot and is located rotor core's axial side, wherein, rotor core's radius R1, stator core's outer radius R2, rotor core's axial height L1 and the distance L2 between rotor core and the magnetic part satisfy, 0.75 is less than or equal to (L2XR2)/(L1XR1) is less than or equal to 1.5, can guarantee that the position of magnetic part can not receive the interference of stator core, the produced magnetic field of rotor core, can guarantee the reading precision of magnetic part to rotor core's position, speed isoparametric, the reliable operation of motor.

Description

Motor, electric power steering system and vehicle

Technical Field

The application relates to the technical field of motor equipment, in particular to a motor, an electric power steering system and a vehicle.

Background

At present, the motor is provided with a magnet for realizing the monitoring of the position and the rotating speed signals of a rotor assembly, the magnet and the rotor assembly synchronously rotate, and the signals are transmitted to an induction chip through a magnetic field.

However, in the motor system, the rotor assembly contains magnetic steel and other parts, which can generate magnetic field signals to affect the magnetic field of the magnet, so that the signal acquisition accuracy of the magnet is reduced or even fails. Similarly, the stator magnetic field generated by the stator assembly of the motor after current is introduced will also interfere with the magnets.

In order to ensure that the magnetic field generated by the rotor assembly and the stator assembly does not affect the collection precision of the magnets, the rotor assembly and the stator assembly should be kept at a sufficient safety distance, but the axial length of the motor is not allowed to be too long in consideration of the miniaturization design and cost control of the motor. Therefore, how to meet the miniaturization requirement of the motor while ensuring the collection precision of the magnet becomes a problem to be solved.

Disclosure of Invention

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

To this end, a first aspect of the present application is to propose an electric machine.

A second aspect of the present application is to provide an electric power steering system.

A third aspect of the present application is directed to a vehicle.

In view of this, according to a first aspect of the present application, there is provided a motor including a stator core provided with a rotor cavity, a rotor core located in the rotor cavity and rotatable relative to the stator core, a rotor core provided with an axial through shaft hole, a portion of the rotor core extending into the shaft hole and being fitted with the rotor core, and a magnetic member provided on the rotor core and located on a shaft side of the rotor core, wherein a radius R1 of the rotor core, an outer radius R2 of the stator core, an axial height L1 of the rotor core, and a distance L2 between the rotor core and the magnetic member are satisfied, and 0.75.ltoreq (l2xr2)/(l1xr1). Ltoreq.1.5.

The motor that this application provided includes stator core, rotor core, pivot and magnetic part, and stator core's inside is equipped with the rotor chamber, and the rotor chamber runs through along the axial and locates on the stator core. The rotor core is located the rotor intracavity, has the clearance between rotor core and the stator core to can ensure that the rotor core can assemble in stator core is inside smoothly, also can ensure simultaneously that the rotor core is when the stator core is rotatory for the rotor core, can not take place the friction between rotor core and the stator core and ensure the safe performance of motor. The rotor core is provided with a shaft hole penetrating along the axial direction, a part of the rotating shaft is positioned in the shaft hole, and the rotating shaft is matched with the stator core. Further, the magnetic part is arranged on the rotating shaft, the magnetic part is positioned on one axial side of the rotor core, namely, the magnetic part is not contacted with the rotor core, the rotating shaft is used as a connecting structure between the magnetic part and the rotor core, the magnetic part, the rotating shaft and the rotor core synchronously rotate in the operation process of the motor, and the magnetic part can acquire position signals, rotating speed signals and the like of the rotor core and the rotating shaft. Wherein the magnetic piece is a permanent magnet. The magnetic piece can generate a magnetic field, and the rotor core is made of a magnetic conductive material. The reasonable range of the distance L2 between the magnetic piece and the rotor core can be determined according to 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 piece and the rotor core meets the relation, the position of the magnetic piece can be ensured not to be interfered by the magnetic field generated by the stator core and the rotor core, the reading precision of the magnetic piece to the parameters such as the position, the speed and the like of the rotor core can be ensured, and the reliable operation of the motor is ensured. When the distance between the magnetic piece and the rotor core exceeds the range, the axial height of the whole motor is too high, so that the motor is not suitable for the miniaturization development trend of the motor on one hand, and the cost of the motor is increased directly on the other hand.

When the value of (l2×r2)/(l1×r1) is lower than 0.75, the strong magnetic fields of the stator core and the rotor core will interfere with the weak magnetic field of the magnetic element, so that the position sensor located in the magnetic induction range of the magnetic element cannot correctly read the rotation speed and the position signal, and serious consequences such as out-of-control motor and stop work are further caused. If the value of (L2×R2)/(L1×R1) is higher than 0.75, this interference can be avoided, but when the value of (L2×R2)/(L1×R1) is higher, the longer the axial length of the motor is, the higher the value is, which can significantly increase the cost of the motor. In summary, it is preferable that the value range of (l2×r2)/(l1×r1) is defined within [0.75,1.5], and the relationship between the distance from the rotor core to the magnetic member and the magnetic induction intensity at the magnetic member is within this range, so that the optimum performance can be obtained.

In one possible design, further, the maximum radius R3 of the magnetic member, the radius R4 of the rotating shaft, and the radius R1 of the rotor core satisfy R4R 3R 1.

In the design, the radius of the magnetic part is larger than that of the rotating shaft and smaller than that of the rotor core, so that the size of the magnetic part is moderate, the aim that the magnetic part is too small to acquire position and rotating speed signals is avoided, and the magnetic part is too small to possibly cause assembly difficulty, aggravate assembly deviation and the like.

The magnetic piece can be directly connected with the rotating shaft or indirectly connected with the rotating shaft, and the magnetic piece and the rotating shaft can synchronously rotate only.

In one possible design, the motor further comprises a connecting seat, a first end of the connecting seat is connected with the rotating shaft, and a second end of the connecting seat is provided with a magnetic piece.

In this design, not the direct connection between pivot and the magnetic part, link to each other through the connecting seat between pivot and the magnetic part promptly, the first end and the pivot of connecting seat are connected, and the second end of connecting seat is used for installing the magnetic part, because the cost of magnetic part, pivot is higher, through setting up the connecting seat, can simplify the structure of magnetic part and pivot, adapt to the connection demand of pivot, magnetic part through the connecting seat to can reduce cost.

In one possible design, further, one end of the shaft is provided with a limit groove. The connecting seat comprises a limiting part and a containing part, and the limiting part stretches into the limiting groove. The storage part is connected with the limiting part, is provided with a storage groove, and the magnetic piece is arranged in the storage groove.

In the design, one end of the rotating shaft is provided with a limiting groove, the limiting groove is axially extended and formed, and a notch of the limiting groove is arranged away from the rotor core. The connecting seat comprises a limiting part and a containing part, wherein the limiting part is axially inserted into the limiting groove, so that reliable connection with the rotating shaft is realized. Further, on the section perpendicular to the axial direction, the cross section of the limiting groove is in a non-perfect circle or a round shape, namely, when the limiting part stretches into the limiting groove, the limiting part and the groove wall of the limiting groove are mutually extruded to form position limitation, and the aim that the rotating shaft drives the magnetic part to synchronously rotate through the connecting seat is achieved. For example, the limiting part is a limiting column, the limiting groove is an axially extending groove body, and the limiting column is inserted into the limiting groove to realize reliable assembly.

The storage part is provided with a storage groove, the magnetic piece is embedded in the storage groove, and the notch of the storage groove is away from the rotor core, so that the magnetic piece is convenient to assemble.

In one possible design, further, the maximum radius R3 of the magnetic element and the maximum radius R5 of the receiving portion satisfy 0.75.ltoreq.R3/R5 < 1.

In this design, the ratio between the maximum radius R3 of the magnetic element and the radius R5 of the accommodating portion satisfies the above range, i.e. the magnetic element is slightly smaller than the accommodating portion, so as to avoid the excessive large accommodating portion and the excessive small magnetic element, and the accommodating portion may cause shielding effect on the magnetic field generated by the magnetic element, thereby affecting the accurate sensing between the magnetic element and the sensing sensor.

It should be noted that the magnetic component can also be directly connected to the limiting portion, that is, the connecting seat only includes the limiting portion and does not have the containing portion, so that the structure is simpler.

In one possible design, further, the accommodating part comprises an accommodating disc and an accommodating rib, and the accommodating disc is connected between the limiting part and the accommodating rib; wherein, the axial height L3 of the storage disc, the maximum axial height L4 of the magnetic piece, the radius R6 of the limiting part and the radius R4 of the rotating shaft are satisfied, and the ratio of R6/R4 to L3/L4 is less than or equal to 0.8 and less than or equal to 1.2.

In this design, accomodate the portion and include accomodate the dish and accomodate the muscle, accomodate the dish and connect between spacing portion and accomodate the muscle, accomodate the dish and be discoid, accomodate the dish and have certain thickness. The storage ribs are connected to the storage disc and extend towards the direction deviating from the rotor core, and the storage disc and the storage ribs enclose to form a storage groove for assembling the magnetic part. The radius of the rotating shaft, the radius of the limiting part, the axial height of the storage disc and the maximum axial height of the magnetic piece are mutually related, so that the four can meet the above relation, the reliable connection performance of the whole connecting seat and the rotating shaft can be ensured, meanwhile, stable and reliable storage can be provided for the magnetic piece, the connecting seat is prevented from being separated from the rotating shaft in the high-speed rotating process, and the magnetic piece is separated from the connecting seat, so that the magnetic piece, the connecting seat and the rotating shaft are reliably connected.

In one possible design, further, the minimum distance L5 between the receiving plate and the rotating shaft is 0.1 mm.ltoreq.L5.ltoreq.2 mm.

In this design, have the clearance between take in dish and the pivot, the clearance is used for providing the pressure equipment allowance, when pressing the connecting seat in the pivot, avoids too big and probably directly presses the pivot with the take in dish, causes the pivot damage. Meanwhile, the arrangement of the gap can also be helpful for identifying the press-fit distance so as to determine whether the connecting seat is installed in place.

In one possible design, further, the radius R6 of the limit portion and the radius R4 of the rotation shaft satisfy 0.2.ltoreq.R6/R4.ltoreq.0.3.

In the design, the radius of the limiting part and the radius of the rotating shaft meet the relation, and the structural strength of the rotating shaft can be prevented from being influenced due to the fact that the volume of the limiting groove on the rotating shaft is overlarge on the premise that reliable support can be provided for the limiting part.

In one possible design, the connection mount is further a metal mount or a plastic mount.

In this design, the connecting seat is integrated into one piece structure, accomodate portion and spacing portion structure as an organic whole promptly, because mechanical properties of integral type structure is good, therefore can improve the joint strength between accomodate portion and the spacing portion, in addition, can make accomodate portion and spacing portion an organic whole, batch production to improve the machining efficiency of product, reduce the processing cost of product. And through the integrated into one piece's structure with storage part and spacing portion design, improved the wholeness of connecting seat, reduced spare part quantity, reduced the installation process, improved installation effectiveness, make the installation of connecting seat more convenient and reliable.

Further, the connecting seat is a metal seat, and is high in structural strength and good in wear resistance. Or the connecting seat is a plastic seat, can be prepared by adopting an injection molding process, has a light structure, is beneficial to reducing the weight of the whole motor, and has low cost.

In one possible design, the motor further comprises a bearing sleeved on the rotating shaft and located on the shaft 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 are met, and 0.45 is less than or equal to (R1-R7) multiplied by L6 is less than or equal to 3.75.

In this design, the motor still includes the cover and establishes at epaxial bearing, and the distance between bearing and the rotor core, the axial height of bearing self and the biggest radius of bearing, rotor core's radius satisfy above-mentioned relation to can guarantee that rotor core can not take place the phenomenon of magnetic leakage because of too near apart from the bearing, lead to the back electromotive force of motor to reduce, the phenomenon of torque inadequately appears. Meanwhile, when the four parameters meet the range requirement, the distance between the bearing and the rotor core can be ensured not to be too large, the increase of the axial size of the motor is avoided, and the increase of the cost is avoided.

Specifically, when the value of (R1-R7) ×l6 is smaller than this range, the counter potential of the motor tends to decrease with the decrease of (R1-R7) ×l6 due to the axial leakage effect, further resulting in a decrease in the output torque of the motor, failing to meet the intended functional requirement. If the value of (R1-R7). Times.L 6 is higher than the minimum value in this range, no leakage flux phenomenon will occur, but too high a value of (R1-R7). Times.L 6 will result in a side length of the motor in the axial direction, further increasing the motor cost. In summary, it is preferable to define the value range of (R1-R7) x L6 within [0.45,3.75], so that the product can be ensured to run reliably, the motor cost is effectively reduced, and the product competitiveness is improved.

In one possible design, the bearing further comprises a first bearing, the motor further comprises a housing having a receiving cavity, the stator core and the rotor core are received in the receiving cavity, and the first bearing is connected to the housing.

In this design, the bearing includes first bearing, and first bearing links to each other with the casing, and the casing can form and hold the chamber to accept stator core, rotor core well, for stator core, rotor core formation good protection, prevent that external environment from interfering with the operation of motor.

In one possible design, the bearing further comprises a second bearing, the second bearing being arranged close to the magnetic member with respect to the first bearing; the motor also comprises an end cover, wherein the end cover is arranged on one axial side of the rotor core, and an elastic gasket is arranged between the second bearing and the end cover.

In this design, the bearing further comprises a second bearing, which is arranged close to the magnetic member with respect to the first bearing, i.e. the second bearing is located between the magnetic member and the rotor core. The motor also comprises an end cover, the end cover is arranged on one axial side of the rotor core, an elastic gasket is arranged between the second bearing and the end cover, and the elastic gasket can buffer vibration generated at the second bearing.

The axial distances among the first bearing, the second bearing and the rotor core all meet the relation, and the axial distance between the first bearing and the rotor core can be equal to or different from the axial distance between the second bearing and the rotor core.

In one possible design, further, the maximum radius R3 of the magnetic member, the radius R4 of the rotating shaft, the radius R1 of the rotor core, and the maximum radius R7 of the second bearing satisfy R4R 3R 7R 1.

In the design, the maximum radius R3 of the magnetic part, the radius R4 of the rotating shaft, the radius R1 of the rotor core and the maximum radius R7 of the second bearing meet the above relation, so that the relative size relation among the magnetic part, the rotating shaft, the rotor core and the second bearing meets a certain relation, the structural arrangement of the motor tends to be more reasonable, and the motor performance is improved.

According to a second aspect of the present application, there is provided an electric power steering system comprising an electric motor provided by any of the designs described above.

The electric power steering system provided by the application comprises the motor provided by any one of the designs, so that the electric power steering system has all the beneficial effects of the motor and is not described in detail herein.

Among them, an electric power steering system (Electric Power Steering, abbreviated as EPS) is a power steering system that directly relies on a motor to provide assist torque, and the EPS system has many advantages over the conventional hydraulic power steering system HPS (Hydraulic Power Steering). The EPS is mainly composed of a torque sensor, a vehicle speed sensor, a motor, a speed reduction mechanism, an Electronic Control Unit (ECU), and the like.

According to a third aspect of the present application there is provided a vehicle comprising an electric machine or an electric power steering system as provided by any of the designs described above.

The vehicle provided by the application comprises the motor or the electric power steering system provided by any one of the designs, so that the vehicle has all the beneficial effects of the motor or the electric power steering system, and the details are not repeated here.

The vehicle can be a traditional fuel vehicle or a new energy vehicle. The new energy automobile comprises a pure electric automobile, a range-extended electric automobile, a hybrid electric automobile, a fuel cell electric automobile, a hydrogen engine automobile and the like.

Additional aspects and advantages of the present application will become apparent in the following description, or may be learned by practice of the present application.

Drawings

The foregoing and/or additional aspects and advantages of the present application will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings, wherein:

FIG. 1 illustrates one of the structural schematic diagrams of an electric machine in accordance with one embodiment of the present application;

FIG. 2 shows a partial schematic of an electric machine in accordance with one embodiment of the present application;

FIG. 3 shows a second schematic diagram of the motor in accordance with one embodiment of the present application;

FIG. 4 is a schematic diagram showing the effect of the magnetic field generated by the rotor core on the inductive sensor;

FIG. 5 illustrates a schematic diagram of rotor core to magnetic element distance versus magnetic induction at a magnetic element according to one embodiment of the present application;

FIG. 6 illustrates a schematic diagram of the distance of a bearing from a rotor core versus back emf in accordance with an embodiment of the present application;

fig. 7 shows a schematic structural diagram of an electric power steering system according to an embodiment of the present application.

Reference numerals:

a 100-degree motor is provided with a motor,

110 a stator core,

120 the rotor core,

130 the spindle is rotated,

140 the magnetic element(s),

150 a connecting seat is connected with the connecting seat,

151 of the two-way valve is provided with a limiting part,

152 receiving portion 1521 receives the disk, 1522 receives the rib,

161, a first bearing, a second bearing 162,

200 an electric power steering system,

211 steering wheel, 212 steering shaft, 213 universal joint, 214 rotation shaft, 215 rack and pinion mechanism, 216 rack shaft, 217 wheels,

221 steering torque sensor, 222 control unit, 223 retarding mechanism.

Detailed Description

In order that the above-recited objects, features and advantages of the present application will be more clearly understood, a more particular description of the application will be rendered by reference to the appended drawings and appended detailed description. It should be noted that, in the case of no conflict, the embodiments of the present application and the features in the embodiments may be combined with each other.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application, however, the present application may be practiced otherwise than as described herein, and thus the scope of the present application is not limited by the specific embodiments disclosed below.

The motor 100, the electric power steering system 200, and the vehicle provided according to some embodiments of the present application are described below with reference to fig. 1 to 7.

According to an embodiment of the first aspect of the present application, as shown in fig. 1, 2 and 3, there is provided a motor 100 including a stator core 110, a rotor core 120, a rotating shaft 130 and a magnetic member 140, wherein the stator core 110 is provided with a rotor cavity, the rotor core 120 is located in the rotor cavity and is rotatable relative to the stator core 110, the rotor core 120 is provided with an axial through shaft hole, a portion of the rotating shaft 130 extends into the shaft hole and is engaged with the rotor core 120, and the magnetic member 140 is provided on the rotating shaft 130 and is located at one axial side of the rotor core 120, wherein a radius R1 of the rotor core 120, an outer radius R2 of the stator core 110, an axial height L1 of the rotor core 120 and a distance L2 between the rotor core 120 and the magnetic member 140 are satisfied by 0.75.ltoreq.l2xr2)/(l1×r1).

The motor 100 that this application provided includes stator core 110, rotor core 120, pivot 130 and magnetic part 140, and stator core 110's inside is equipped with the rotor chamber, and the rotor chamber runs through along the axial and locates on the stator core 110. The rotor core 120 is located in the rotor cavity, and a gap is provided between the rotor core 120 and the stator core 110, so that the rotor core 120 can be ensured to be smoothly assembled inside the stator core 110, and the rotor core 120 can be ensured to rotate relative to the stator core 110, and the rotor core 120 and the stator core 110 can not be rubbed to ensure the safe use performance of the motor 100. The rotor core 120 is provided with a shaft hole penetrating in the axial direction, a part of the rotating shaft 130 is positioned in the shaft hole, and the rotating shaft 130 is matched with the stator core 110. Further, the magnetic element 140 is disposed on the rotating shaft 130, and the magnetic element 140 is located at one axial side of the rotor core 120, that is, the magnetic element 140 is not in contact with the rotor core 120, the rotating shaft 130 is used as a connection structure between the magnetic element 140 and the rotor core 120, and in the operation process of the motor 100, the magnetic element 140, the rotating shaft 130 and the rotor core 120 synchronously rotate, and the magnetic element 140 can collect position signals, rotation speed signals and the like of the rotor core 120 and the rotating shaft 130. Wherein the magnetic member 140 is a permanent magnet. The magnetic member 140 is capable of generating a magnetic field, and the rotor core 120 is made of a magnetically conductive material. The reasonable range of the distance L2 between the magnetic element 140 and the rotor core 120 can be determined according to the radius of the rotor core 120, the outer radius of the stator core 110 and the axial height of the rotor core 120, and when the distance between the magnetic element 140 and the rotor core 120 satisfies the above relationship, the position of the magnetic element 140 can be ensured not to be interfered by the magnetic field generated by the stator core 110 and the rotor core 120, the reading accuracy of the magnetic element 140 to the parameters such as the position, the speed and the like of the rotor core 120 can be ensured, and the reliable operation of the motor 100 can be ensured. When the distance between the magnetic member 140 and the rotor core 120 exceeds the above range, the axial height of the motor 100 is too high, which is not suitable for the trend of miniaturization of the motor 100, and directly leads to the cost increase of the motor 100.

When the value of (l2×r2)/(l1×r1) is lower than 0.75, the strong magnetic fields of the stator core 110 and the rotor core 120 interfere with the weak magnetic field of the magnetic element 140, which results in that the position sensor located in the magnetic induction range of the magnetic element 140 cannot correctly read the rotation speed and the position signal, and further causes serious consequences such as out of control and stop of the motor 100. If the value of (l2×r2)/(l1×r1) is higher than 0.75, this interference can be avoided, but when the value of (l2×r2)/(l1×r1) is higher, the longer the axial length of the motor 100 is, the higher the value is, which significantly increases the cost of the motor 100. In summary, it is preferable to define the value range of (l2×r2)/(l1×r1) within [0.75,1.5], in which the relationship between the distance from the rotor core 120 to the magnetic member 140 and the magnetic induction intensity at the magnetic member 140 is as shown in fig. 4 and 5, and the optimum performance can be obtained.

Further, the maximum radius R3 of the magnetic member 140, the radius R4 of the rotating shaft 130, and the radius R1 of the rotor core 120 satisfy R4. Ltoreq.R3.ltoreq.R1.

In this embodiment, the radius of the magnetic element 140 is larger than the radius of the rotating shaft 130 and smaller than the radius of the rotor core 120, so that the size of the magnetic element 140 can be moderate, the magnetic element 140 is prevented from being too small to achieve the purpose of collecting position and rotation speed signals, and the magnetic element 140 is also likely to cause difficult assembly and aggravate assembly deviation when too small.

The magnetic member 140 may be directly connected to the rotating shaft 130, or the magnetic member 140 may be indirectly connected to the rotating shaft 130, so long as the two can rotate synchronously.

Further, as shown in fig. 1, 2 and 3, the motor 100 further includes a connecting seat 150, a first end of the connecting seat 150 is connected with the rotating shaft 130, and a second end of the connecting seat 150 is provided with a magnetic member 140.

In this embodiment, the rotating shaft 130 is not directly connected to the magnetic member 140, that is, the rotating shaft 130 is connected to the magnetic member 140 through the connecting seat 150, the first end of the connecting seat 150 is connected to the rotating shaft 130, and the second end of the connecting seat 150 is used for installing the magnetic member 140, because the cost of the magnetic member 140 and the rotating shaft 130 is high, by providing the connecting seat 150, the structures of the magnetic member 140 and the rotating shaft 130 can be simplified, and the connecting requirements of the rotating shaft 130 and the magnetic member 140 can be met through the connecting seat 150, thereby reducing the cost.

Further, as shown in fig. 2 and 3, one end of the rotating shaft 130 is provided with a limit groove. The connecting seat 150 comprises a limiting part 151 and a containing part 152, and the limiting part 151 extends into the limiting groove. The storage portion 152 is connected to the limiting portion 151, the storage portion 152 is provided with a storage groove, and the magnetic member 140 is disposed in the storage groove.

In this embodiment, a limiting groove is disposed at one end of the rotating shaft 130, and the limiting groove is axially extended and disposed with a notch of the limiting groove facing away from the rotor core 120. The connection seat 150 includes a limiting portion 151 and a receiving portion 152, and the limiting portion 151 is axially inserted into the limiting groove, so as to achieve reliable connection with the rotating shaft 130. Further, on the cross section perpendicular to the axial direction, the cross section of the limiting groove is non-circular or circular, i.e. when the limiting portion 151 extends into the limiting groove, the limiting portion 151 and the groove wall of the limiting groove can be mutually extruded to form a position limitation, so that the purpose that the rotating shaft 130 drives the magnetic component 140 to synchronously rotate through the connecting seat 150 is achieved. For example, the limiting part 151 is a limiting column, the limiting groove is an axially extending groove body, and the limiting column is inserted into the limiting groove to realize reliable assembly.

The accommodating portion 152 has an accommodating groove, the magnetic member 140 is embedded in the accommodating groove, and a notch of the accommodating groove is arranged away from the rotor core 120, so that the magnetic member 140 is convenient to assemble.

Further, as shown in fig. 1, 2 and 3, the maximum radius R3 of the magnetic member 140 and the maximum radius R5 of the receiving portion 152 satisfy 0.75R 3/R5 < 1.

In this embodiment, the ratio between the maximum radius R3 of the magnetic element 140 and the radius R5 of the receiving portion 152 is within the above range, i.e. the magnetic element 140 is slightly smaller than the receiving portion 152, so that the receiving portion 152 is prevented from being too large and the magnetic element 140 is prevented from being too small, and the receiving portion 152 may shield the magnetic field generated by the magnetic element 140, thereby affecting the accurate sensing between the magnetic element 140 and the sensor.

It should be noted that, the magnetic member 140 may be directly connected to the limiting portion 151, that is, the connecting seat 150 only includes the limiting portion 151 and does not have the receiving portion 152, so that the structure is simpler.

Further, as shown in fig. 1, 2 and 3, the housing portion 152 includes a housing plate 1521 and a housing rib 1522, the housing plate 1521 being connected between the limiting portion 151 and the housing rib 1522; wherein the axial height L3 of the storage disc 1521, the maximum axial height L4 of the magnetic member 140, the radius R6 of the limiting portion 151, and the radius R4 of the rotating shaft 130 are all equal to or less than 0.8 (R6/R4)/(L3/L4) and equal to or less than 1.2.

In this embodiment, the housing portion 152 includes a housing plate 1521 and a housing rib 1522, the housing plate 1521 is connected between the limiting portion 151 and the housing rib 1522, the housing plate 1521 has a disc shape, and the housing plate 1521 has a certain thickness. The storage ribs 1522 are connected to the storage disk 1521 and extend in a direction away from the rotor core 120, and the storage disk 1521 and the storage ribs 1522 enclose to form storage slots for assembling the magnetic members 140. The radius of the rotating shaft 130, the radius of the limiting portion 151, the axial height of the storage disc 1521 and the maximum axial height of the magnetic member 140 are related to each other, so that the four satisfy the above relation, thereby ensuring reliable connection performance between the whole connecting seat 150 and the rotating shaft 130, and simultaneously providing stable and reliable storage for the magnetic member 140, preventing the connecting seat 150 from being separated from the rotating shaft 130 during high-speed rotation, and ensuring reliable connection among the magnetic member 140, the connecting seat 150 and the rotating shaft 130 due to the separation of the magnetic member 140 from the connecting seat 150.

Further, as shown in fig. 1, 2 and 3, the minimum distance L5 between the housing disk 1521 and the rotating shaft 130 satisfies 0.1 mm.ltoreq.l5.ltoreq.2mm.

In this embodiment, a gap is formed between the receiving disc 1521 and the rotating shaft 130, and the gap is used for providing a press-fit allowance, so that the receiving disc 1521 is prevented from being directly pressed against the rotating shaft 130 due to excessive pressure when the connecting seat 150 is pressed onto the rotating shaft 130, thereby damaging the rotating shaft 130. At the same time, the provision of the gap can also help to identify the press-fit distance to determine whether the connection mount 150 is in place.

Further, as shown in fig. 1, 2 and 3, the radius R6 of the limiting portion 151 and the radius R4 of the rotating shaft 130 satisfy 0.2R 6/R4 0.3.

In this embodiment, the radius of the limiting portion 151 and the radius of the rotating shaft 130 satisfy the above relationship, and the structural strength of the rotating shaft 130 itself can be prevented from being affected by the excessive volume of the limiting groove on the rotating shaft 130 on the premise that reliable support provided to the limiting portion 151 is ensured.

Further, the connection base 150 is a metal base or a plastic base.

In this embodiment, the connecting seat 150 is of an integral structure, that is, the accommodating portion 152 and the limiting portion 151 are of an integral structure, because the mechanical property of the integral structure is good, the connection strength between the accommodating portion 152 and the limiting portion 151 can be improved, in addition, the accommodating portion 152 and the limiting portion 151 can be integrally manufactured, and mass production can be performed, so that the processing efficiency of the product is improved, and the processing cost of the product is reduced. And, through the integrated into one piece's structure with storage 152 and spacing 151, improved the wholeness of connecting seat 150, reduced spare part quantity, reduced the installation process, improved installation effectiveness, make the installation of connecting seat 150 more convenient and reliable.

Further, the connection base 150 is a metal base, and has high structural strength and good wear resistance. Alternatively, the connecting seat 150 is a plastic seat, and can be manufactured by injection molding, so that the structure is light, the weight of the whole motor 100 is reduced, and the cost is low.

Further, as shown in fig. 1, 3 and 6, the motor 100 further includes a bearing which is fitted over the rotation shaft 130 and located on the shaft side of the rotor core 120, wherein a distance L6 between the bearing and the rotor core 120, a maximum radius R7 of the bearing, and a radius R1 of the rotor core 120 are satisfied, and 0.45.ltoreq.r 1-R7.xl6.ltoreq.3.75.

In this embodiment, the motor 100 further includes a bearing sleeved on the rotating shaft 130, where the distance between the bearing and the rotor core 120, the axial height of the bearing, the maximum radius of the bearing, and the radius of the rotor core 120 satisfy the above relationships, so that it can be ensured that the phenomenon of magnetic leakage of the rotor core 120 due to too close distance to the bearing does not occur, resulting in reduction of counter potential of the motor 100 and occurrence of insufficient torque. Meanwhile, when the above four parameters satisfy the range requirement, it is possible to ensure that the distance between the bearing and the rotor core 120 is not excessively large, to avoid an increase in the axial dimension of the motor 100, and to avoid an increase in cost.

Specifically, as shown in fig. 6, when the value of (R1-R7) ×l6 is smaller than this range, the counter potential of the motor 100 tends to decrease with the decrease of (R1-R7) ×l6 due to the axial leakage effect, further resulting in a decrease of the output torque of the motor 100, failing to meet the intended functional requirement. If the value of (R1-R7) ×l6 is higher than the minimum value in this range, no leakage flux phenomenon occurs, but an excessively high value of (R1-R7) ×l6 leads to a further increase in the axial length side length of the motor 100, and the cost of the motor 100. In summary, it is preferable to define the value range of (R1-R7) ×l6 within [0.45,3.75], so that the product can be ensured to run reliably, the cost of the motor 100 is effectively reduced, and the product competitiveness is improved.

Further, as shown in fig. 1, the bearing includes a first bearing 161, and the motor 100 further includes a housing having a receiving cavity, in which the stator core 110 and the rotor core 120 are received, and the first bearing 161 is connected to the housing.

In this embodiment, the bearings include a first bearing 161, where the first bearing 161 is connected to a casing, and the casing can form a receiving cavity to well receive the stator core 110 and the rotor core 120, so as to well protect the stator core 110 and the rotor core 120 and prevent the external environment from interfering with the operation of the motor 100.

Further, as shown in fig. 1, the bearing further includes a second bearing 162, the second bearing 162 being disposed adjacent to the magnetic member 140 with respect to the first bearing 161; the motor 100 further includes an end cover provided at one axial side of the rotor core 120, and an elastic washer is provided between the second bearing 162 and the end cover.

In this embodiment, the bearing further comprises a second bearing 162, the second bearing 162 being arranged close to the magnetic member 140 with respect to the first bearing 161, i.e. the second bearing 162 is located between the magnetic member 140 and the rotor core 120. The motor 100 further includes an end cover disposed at one axial side of the rotor core 120, and an elastic washer is disposed between the second bearing 162 and the end cover, and is capable of buffering vibration generated at the second bearing 162.

The axial distances between the first bearing 161, the second bearing 162, and the rotor core 120 satisfy the above-described relational expression, and the axial distance between the first bearing 161 and the rotor core 120 may be equal to or different from the axial distance between the second bearing 162 and the rotor core 120.

Further, as shown in FIG. 1, the maximum radius R3 of the magnetic member 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 R4R 3R 7R 1.

In this embodiment, the maximum radius R3 of the magnetic member 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 member 140, the rotating shaft 130, the rotor core 120, and the second bearing 162 satisfies a certain relationship, thereby making the structural arrangement of the motor 100 more reasonable and facilitating the improvement of the performance of the motor 100.

According to an embodiment of the second aspect of the present application, as shown in fig. 7, there is provided an electric power steering system 200 including the motor 100 provided by any of the designs described above.

The electric power steering system 200 provided in the present application includes the motor 100 provided by any of the above designs, so that the electric power steering system has all the beneficial effects of the motor 100, and will not be described herein.

Among them, the electric power steering system 200, (Electric Power Steering, abbreviated as EPS) is a power steering system that directly relies on the motor 100 to provide assist torque, and compared with the conventional hydraulic power steering system HPS (Hydraulic Power Steering), the EPS system has a simple structure and flexible assembly, and can save energy and protect the environment, and most of the vehicle types of modern vehicles are basically equipped with the EPS system.

Among other things, the electric power steering system 200 includes a variety of realizable approaches. One of many possible ways will be specifically described below. Specifically, in one embodiment, an EPS system has a steering system and an assist torque mechanism that generates an assist torque. The EPS system generates assist torque that assists steering torque of a steering system generated by a driver operating a steering wheel. By the assist torque, the burden of the operation of the driver is reduced.

The steering system specifically includes a steering wheel 211, a steering shaft 212, a universal joint 213, a rotating shaft 214, a rack and pinion mechanism 215, a rack shaft 216, left and right steering wheels 217, and the like.

The assist torque mechanism specifically includes a steering torque sensor 221, an Electronic Control Unit (ECU) 222 for an automobile, a motor, a speed reduction mechanism 223, and the like. 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 of the steering torque sensor 221. The motor generates an assist torque corresponding to the steering torque based on the drive signal. The electric machine transmits the generated assist torque to the steering system via the reduction mechanism 223.

According to an embodiment of the third aspect of the present application, there is provided a vehicle comprising the motor 100 or the electric power steering system 200 provided by any of the designs described above.

The vehicle provided by the application includes the motor 100 or the electric power steering system 200 provided by any one of the above designs, so that the vehicle has all the beneficial effects of the motor 100 or the electric power steering system 200, and will not be described herein.

In the present application, the term "plurality" means two or more, unless explicitly defined otherwise. The terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; "coupled" may be directly coupled or indirectly coupled through intermediaries. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art as the case may be.

In the description of the present specification, the terms "one embodiment," "some embodiments," "particular embodiments," and the like, mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The foregoing description is only of the preferred embodiments of the present application and is not intended to limit the same, but rather, various modifications and variations may be made by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. An electric machine, comprising:

the stator core is provided with a rotor cavity;

the rotor core is positioned in the rotor cavity and can rotate relative to the stator core, and the rotor core is provided with an axial hole penetrating axially;

a rotating shaft, wherein a part of the rotating shaft extends into the shaft hole and is matched with the rotor core;

the magnetic piece is arranged on the rotating shaft and is positioned at one axial side of the rotor core;

wherein 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 piece are satisfied,

0.75≤(L2×R2)/(L1×R1)≤1.5。

2. an electric machine according to claim 1, characterized in that,

the maximum radius R3 of the magnetic piece, the radius R4 of the rotating shaft and the radius R1 of the rotor core are met, and R4 is more than or equal to R3 and less than or equal to R1.

3. The electric machine of claim 1, further comprising:

the first end of connecting seat with the pivot is connected, the second end of connecting seat is equipped with the magnetic part.

4. The motor of claim 3, wherein the motor is configured to control the motor,

one end of the rotating shaft is provided with a limit groove;

the connecting seat comprises:

the limiting part extends into the limiting groove;

and the storage part is connected with the limiting part and is provided with a storage groove, and the magnetic piece is arranged in the storage groove.

5. The motor of claim 4, wherein the motor is configured to control the motor to drive the motor,

the maximum radius R3 of the magnetic piece and the maximum radius R5 of the containing part are satisfied, and R3/R5 is more than or equal to 0.75 and less than 1.

6. The motor of claim 4, wherein the motor is configured to control the motor to drive the motor,

the storage part comprises a storage disc and storage ribs, and the storage disc is connected between the limiting part and the storage ribs; wherein, the liquid crystal display device comprises a liquid crystal display device,

the axial height L3 of the storage disc, the maximum axial height L4 of the magnetic piece, the radius R6 of the limiting part and the radius R4 of the rotating shaft are satisfied,

0.8≤(R6/R4)/(L3/L4)≤1.2。

7. the motor of claim 6, wherein the motor is configured to control the motor,

the minimum distance L5 between the storage disc and the rotating shaft is more than or equal to 0.1mm and less than or equal to 2mm.

8. The motor of claim 4, wherein the motor is configured to control the motor to drive the motor,

the radius R6 of the limiting part and the radius R4 of the rotating shaft are met, and R6/R4 is more than or equal to 0.2 and less than or equal to 0.3.

9. The motor of claim 3, wherein the motor is configured to control the motor,

the connecting seat is a metal seat or a plastic seat.

10. The motor according to any one of claims 1 to 9, characterized in that the motor further comprises:

a bearing sleeved on the rotating shaft and positioned at the shaft side of the rotor core,

wherein a distance L6 between the bearing and the rotor core, a maximum radius R7 of the bearing and a radius R1 of the rotor core are satisfied,

0.45≤(R1-R7)×L6≤3.75。

11. the motor of claim 10, wherein the motor is configured to control the motor,

the bearing comprises a first bearing;

the motor further includes:

the shell is provided with an accommodating cavity, the stator core and the rotor core are accommodated in the accommodating cavity, and the first bearing is connected with the shell.

12. The motor of claim 11, wherein the motor is configured to control the motor,

the bearing further comprises a second bearing disposed adjacent to the magnetic member relative to the first bearing;

the motor further includes:

and the end cover is arranged on one axial side of the rotor core, and an elastic gasket is arranged between the second bearing and the end cover.

13. The motor of claim 12, wherein the motor is configured to control the motor,

the maximum radius R3 of the magnetic piece, the radius R4 of the rotating shaft, the radius R1 of the rotor iron core and the maximum radius R7 of the second bearing are met, and R4 is more than or equal to R3 and less than or equal to R7 and less than or equal to R1.

14. An electric power steering system, comprising: an electrical machine as claimed in any one of claims 1 to 13.

15. A vehicle, characterized by comprising: an electric machine as claimed in any one of claims 1 to 13, or an electric power steering system as claimed in claim 14.