CN114498985A

CN114498985A - Rotor of in-wheel motor

Info

Publication number: CN114498985A
Application number: CN202111556868.6A
Authority: CN
Inventors: 王加许; 王健; 张忠
Original assignee: TAIZHOU JINYU ELECTROMECHANICAL CO Ltd
Current assignee: TAIZHOU JINYU ELECTROMECHANICAL CO Ltd
Priority date: 2021-12-18
Filing date: 2021-12-18
Publication date: 2022-05-13

Abstract

The invention relates to a rotor of a hub motor, which comprises a rim, an inner ring body and a permanent magnet, wherein the inner ring body is positioned on the inner side of the rim and fixedly connected with the rim, the permanent magnet is positioned on the inner side surface of the inner ring body, a first mounting surface and a second mounting surface are respectively arranged at two axial ends of the inner ring body, a plurality of fixing holes are respectively arranged on the first mounting surface and the second mounting surface, the hole centers of the fixing holes on the first mounting surface are positioned on the outer side of the circumferential surface of the second inner side, and the hole centers of the fixing holes on the second mounting surface are positioned on the inner side of the circumferential surface of the second inner side. The invention breaks the limit that the wall thickness of the conventional inner ring body is larger than the aperture of the fixed thread, and through the zigzag dislocation offset of the fixed hole, the fixed connection mode of the end cover and the rotor of the conventional motor is continued, the wall thickness of the inner ring body is greatly reduced, and the light-weight design of the motor is realized.

Description

Rotor of in-wheel motor

Technical Field

The invention relates to a rotor of a hub motor, and belongs to the technical field of electric vehicles.

Background

The electric vehicle has the characteristics of light travel, low carbon, environmental protection, energy conservation, safety, reliability, stable performance and the like, and is widely applied to daily life traffic. With the gradual standardization of national policies, the requirements of new national standard two-wheeled electric vehicles are increased sharply, and the compliant electric vehicles have strict limits on the weight of the whole vehicle, so that the aim of pursuing light weight reduction of the whole vehicle is achieved, and the electric vehicle becomes the design target of vast new national standard two-wheeled electric vehicle manufacturers. The weight of the hub motor serving as a core component of the electric two-wheel vehicle occupies a small share in the weight of the whole vehicle, and how to realize the weight reduction of the hub motor is a long-term demand of vast two-wheel electric vehicle enterprises for motor manufacturers.

Among the prior art, the used in-wheel motor's of two-wheeled electric motor car core component is stator and rotor, the rotor cover is established in the stator outside, the rotor includes the rim, interior ring body and permanent magnet, the interior ring body of present electric motor rotor is the straight cylinder column tourus that the sheet material book system that even wall thickness formed, axial both sides terminal surface is material thickness terminal surface itself, the fixed orifices centre of a hole that the terminal surface was established is located between the inside and outside periphery of interior ring body, this just leads to whole interior ring body wall thickness must be greater than the diameter of fixed screw, be greater than more than 5mm at least, interior ring body part magnetic circuit is surplus but can't the attenuate because of the fixed knot constructs the requirement, interior ring body weight is heavy, cause the material waste.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a rotor of an in-wheel motor with a reduced inner ring wall thickness.

The technical scheme adopted by the invention for realizing the purpose is as follows:

the utility model provides an in-wheel motor's rotor, includes rim, interior ring body and permanent magnet, interior ring body be located the inboard of rim and with rim fixed connection, the permanent magnet is located the medial surface of interior ring body, the axial both ends of interior ring body are equipped with first installation face and second installation face respectively, first installation face with all be equipped with a plurality of fixed orificess on the second installation face, the medial surface of interior ring body is the inboard periphery of second, on the first installation face the hole center of fixed orificess is located the outside of the inboard periphery of second, on the second installation face the hole center of fixed orificess is located the inboard of the inboard periphery of second.

As a further optimization of the above technical solution: the first mounting surface, the second mounting surface, and the second inner circumferential surface are distributed approximately in a zigzag shape on a rotational section of the inner ring.

As a further optimization of the above technical solution: the two axial ends of the inner ring body protrude and are respectively turned inwards and outwards to form two annular opening grooves, the rotating profile structure of the inner ring body is approximate to an S shape, and the first mounting surface and the second mounting surface are end surfaces of the two annular opening grooves which are opposite to each other.

As a further optimization of the above technical solution: the annular opening groove is internally provided with a plurality of fixing blocks, the fixing holes correspond to the fixing blocks one to one, internal threads are formed on the fixing blocks, and the fixing holes are communicated with the inside of the fixing blocks to form threaded holes.

Compared with the prior art, the invention has the advantages and beneficial effects that:

according to the rotor of the in-wheel motor, the installation end face of the motor is formed by respectively inward and outward rolling the two axial sides of the inner ring body of the motor rotor, the limit that the wall thickness of the conventional inner ring body is larger than the aperture of the fixed thread is broken, the fixed connection mode of the end cover of the conventional motor and the rotor is continued through the zigzag dislocation offset of the fixed hole, the wall thickness of the inner ring body is greatly reduced, the wall thickness of the conventional motor is reduced to 1 mm-3 mm from the wall thickness of about 5 mm-7 mm of the conventional motor, the material consumption of the inner ring body is greatly reduced, the light weight design of the motor is realized, the weight of the inner ring body is reduced by more than 25%, and the material cost is also greatly reduced.

According to the rotor of the hub motor, the wall thickness of the inner ring body is reasonably designed by designing the wall thickness of the inner ring body, the characteristic that a rim material is a magnetic conductive material is utilized, the material rolling wall thickness of the inner ring body is reasonably designed, sufficient effective magnetic flux of the rotor is guaranteed, meanwhile, the wall thickness of the inner ring body is reduced, the inner space of the motor is expanded, the pasting inner diameter of a permanent magnet is enlarged, the outer diameter of a stator is correspondingly enlarged, compared with a conventional motor, the electromagnetic torque force arm of the motor is greatly increased, compared with the existing hub motor, under the condition of the same tyre installation size, the force arm is increased by 2% -7%, the output torque of the motor is increased by 5% -10%, meanwhile, the inner space of the motor is increased, and the heat dissipation and the power density of the motor are favorably improved.

Compared with the prior art, the rotor of the hub motor provided by the invention has the advantages that the inner ring structure is optimized, the magnetic energy utilization rate and the rotor strength of the motor are guaranteed based on the electromagnetic circuit design of magnetic circuit saturation, the inner ring material is saved, the motor is lightened and reduced in cost, meanwhile, the electromagnetic force arm of the motor is lengthened, the motor torque is increased, in addition, the internal space of the motor is increased, and the heat radiation performance of the motor is improved.

Drawings

Fig. 1 is a schematic cross-sectional structure of the present invention.

FIG. 2 is a schematic cross-sectional view of the inner ring body of the present invention.

FIG. 3 is a cross-sectional view of the present invention.

Fig. 4 is a schematic top view of the present invention.

Fig. 5 is an enlarged schematic view of a portion a in fig. 3.

Fig. 6 is a schematic view of the structure of fig. 5 engaged with the fixing block.

In the figure, 1, the rim; 2. an inner ring body; 3. a permanent magnet; 4. a fixing hole; 5. a fixed block; 11. a first inner circumferential surface; 12. the tyre installing surface of the rim; 21. a first mounting surface; 22. a second mounting surface; 23. a second inner circumferential surface; 24. an outer circumferential surface; 25. an annular open recess.

Detailed Description

The invention is further described with reference to the following figures and detailed description. As shown in fig. 1 to 6, a rotor of an in-wheel motor, which is suitable for a 10-inch electric vehicle, includes a rim 1, an inner ring 2 and a permanent magnet 3, wherein the inner ring 2 is located inside the rim 1. The inner side surface of the rim 1 is a first inner circumferential surface 11, and the inner and outer side surfaces of the inner ring 2 are a second inner circumferential surface 23 and an outer circumferential surface 24, respectively. The first inner circumferential surface 11 and the outer circumferential surface 24 are in close contact with each other, and the inner ring body 2 and the rim 1 are fixedly connected. The permanent magnet 3 is located on the second inner circumferential surface 23. The size of the tread surface 12 of the rim 1 in the embodiment accords with the standard of the 10-inch rim 1, and the first inner circumferential surface 11 is tightly attached to the outer circumferential surface 24 to play a role in mutual fixing and supporting.

In the above technical scheme: the two ends of the inner ring body 2 in the axial direction are respectively provided with a first mounting surface 21 and a second mounting surface 22, and the first mounting surface 21, the second mounting surface 22 and a second inner circumferential surface 23 are distributed in a Z shape on the rotating section of the inner ring body 2. The first mounting surface 21 and the second mounting surface 22 are provided with a plurality of fixing holes 4. The axial both ends of interior ring 2 still are equipped with a plurality of fixed blocks 5, and fixed orifices 4 and fixed block 5 one-to-one have the internal thread on the fixed block 5, and the inside intercommunication of fixed orifices 4 and fixed block 5 forms the screw hole. Through the structure of the dislocation of fixed orifices 4, the effectual wall thickness that has attenuate interior ring member 2 realizes that the lightweight of motor falls this design, satisfies the feasibility of manufacturing. Meanwhile, the integral structure of the inner ring body 2 with one large end and one small end is realized, the small end face, namely one side of the second mounting face 22, can smoothly pass through the first inner side circumferential face 11, and the large end face, namely one side of the first mounting face 21, can ensure enough fastening space.

In the above technical scheme: the two axial ends of the inner ring body 2 are protruded and are respectively rolled inwards and outwards to form two annular opening grooves 25, and the rotating section structure of the inner ring body 2 is similar to an S shape. The two annular open grooves 25 are arranged opposite to each other and offset from each other. The first mounting surface 21 and the second mounting surface 22 are end surfaces of two annular open grooves 25 opposite to each other. The fixing block 5 is positioned in the annular opening groove 25, and the fixing block 5 is fixed in the annular opening groove 25 in an embedding manner. The annular opening groove 25 increases the contact area between the fixing block 5 and the inner ring 2, so that the fixing between the fixing block 5 and the inner ring 2 is more firm. The axial two sides of the inner ring body 2 are turned inwards and outwards to form an approximately S-shaped structure, the structure fully ensures the feasibility of the forming process of the inner ring body 2, a plurality of fixing blocks 5 are embedded into annular opening grooves 25 formed by the S-shaped turning, threaded holes are formed by matching the fixing blocks 5 with the fixing holes 4, screws are arranged in the threaded holes, the motor end cover and the inner ring body 2 are fixed, the Z-shaped distribution fastening structure of the mounting surface is realized, and the sufficient fastening strength is ensured.

In the above technical scheme: the center of the hole of the fixing hole 4 on the first mounting surface 21 is located outside the second inner circumferential surface 23, and the center of the hole of the fixing hole 4 on the second mounting surface 22 is located inside the second inner circumferential surface 23.

In the above technical scheme: the valve hole of the rim 1 is located on the second mounting surface 22, and a valve is mounted on the valve hole. The valve hole of the wheel rim 1 is on the same side as the second mounting surface 22, so that the valve installation and the outer circumferential surface 24 are prevented from seriously interfering to cause the failure of the valve. The permanent magnets 3 are distributed in the second inner circumferential surface 23 in an "N-S" polarity. The inner ring body 2 and the rim 1 are fixed by welding. The outer diameter of the stator of the motor is 219 mm-221 mm. The stator stack height is 12 mm-60 mm, and the motor adopts a permanent magnet structure that 48 slots are matched with 26 antipodes or 48 slots are matched with 22 antipodes.

In the above technical scheme: the diameter of the second inner circumferential surface 23 is 220mm to 226mm, preferably, the diameter of the second inner circumferential surface 23 is 223mm to 225mm, more preferably, the diameter of the second inner circumferential surface 23 is 223.5mm to 224.5mm, and in this embodiment, the diameter of the second inner circumferential surface 23 is 223.95mm to 224.1 mm. According to the scheme, on the basis of reasonable magnetic circuit of the motor, the internal space of the motor is enlarged to the maximum extent, particularly the diameter of the circumferential surface of the motor magnetic steel is pasted, the electromagnetic force arm is lengthened, and the output torque of the motor is increased.

In the above technical scheme: the inner ring body 2 has a thin-walled rotary ring structure, and has a wall thickness of 1.0mm to 3.0mm, preferably 1.2mm to 1.8mm, and more preferably 1.5mm to 1.6 mm. In this example, the wall thickness was 1.6 mm. This embodiment has considered the tensile attenuation back of interior ring member 2, and each part can guarantee sufficient structural strength to and leave sufficient machining allowance for follow-up processing, and simultaneously, interior ring member 2 adds up 1 wall thickness of rim, has constituted rotor yoke portion jointly, has optimized the rotor magnetic circuit, has promoted the magnetic energy utilization ratio.

According to the rotor of the in-wheel motor, the limitation that the wall thickness of the inner ring body needs to be larger than the diameter of the thread hole is effectively avoided through the internal and external dislocation offset of the fixing holes at two axial sides of the inner ring body and the layout of the Z-shaped mounting surface, the wall thickness of the inner ring body is successfully reduced, and the light weight and cost reduction design is realized. The S-shaped rotary section structure of the inner ring body 2 forms an annular opening groove 25, and the structure of the fixing block 5 is additionally arranged in the annular opening groove 25, so that the defect that the fastening strength of the thin-wall mounting surface is not enough is effectively overcome.

The hub motor applied to the rotor of the hub motor fully utilizes the characteristic that the rim material is a magnetic conductive material, and combines the magnetic conductive material of the inner ring body to jointly form the yoke part of the magnetic conductive of the rotor, so that the magnetic circuit of the motor is reasonably optimized, the inner diameter of the motor is expanded, the torque of the motor is improved, in addition, the space in the motor is larger, the heat dissipation characteristic of the motor is further improved, the working temperature rise of the motor is lower, and the power density is higher.

The above embodiments are only preferred embodiments of the present invention, which are only used for illustrating the technical solutions of the present invention, and are not meant to limit the patent scope of the present invention, and all modifications or equivalent substitutions that are made to the technical solutions of the present invention by using the contents of the description and the drawings of the present invention, or directly or indirectly applied to other related technical fields, are included in the patent protection scope of the present invention.

Although the terms rim 1, inner ring 2, permanent magnet 3, fixing hole 4, fixing block 5, first inner circumferential surface 11, tire-mounting surface 12 of rim, first mounting surface 21, second mounting surface 22, second inner circumferential surface 23, outer circumferential surface 24, annular opening groove 25, etc. are used more herein, the possibility of using other terms is not excluded. These terms are used merely to more conveniently describe and explain the nature of the present invention; they are to be construed as being without limitation to any additional limitations that may be imposed by the spirit of the present invention.

Claims

1. A rotor of a hub motor comprises a rim (1), an inner ring body (2) and a permanent magnet (3), the inner ring body (2) is positioned on the inner side of the rim (1) and is fixedly connected with the rim (1), the permanent magnet (3) is positioned on the inner side surface of the inner ring body (2), it is characterized in that two axial ends of the inner ring body (2) are respectively provided with a first mounting surface (21) and a second mounting surface (22), the first mounting surface (21) and the second mounting surface (22) are both provided with a plurality of fixing holes (4), the inner side surface of the inner ring body (2) is a second inner circumferential surface (23), the hole center of the fixing hole (4) on the first mounting surface (21) is positioned on the outer side of the second inner circumferential surface (23), the hole center of the fixing hole (4) on the second mounting surface (22) is positioned on the inner side of the second inner circumferential surface (23).

2. A rotor of an in-wheel electric machine according to claim 1, characterized in that said first mounting surface (21), said second mounting surface (22) and said second inner circumferential surface (23) are approximately "Z" -shaped in a rotational cross-section of said inner ring body (2).

3. The rotor of an in-wheel motor according to claim 1, characterized in that two axial ends of the inner ring body (2) are protruded and are respectively rolled inwards and outwards to form two annular open grooves (25), the rotating section structure of the inner ring body (2) is approximately S-shaped, and the first mounting surface (21) and the second mounting surface (22) are respectively the end surfaces of the two annular open grooves (25) which are opposite to each other.

4. A rotor of an in-wheel motor according to claim 3, characterized in that a plurality of fixing blocks (5) are provided in the annular opening groove (25), the fixing holes (4) correspond to the fixing blocks (5) one to one, internal threads are formed on the fixing blocks (5), and the fixing holes (4) communicate with the inside of the fixing blocks (5) to form threaded holes.