Axial flux motor

Abstract

The invention provides an axial magnetic flux motor which comprises two stators and a rotor, the rotor comprises a rotor iron core and magnetic steel, the two axial sides of the rotor iron core are respectively provided with the magnetic steel composed of a Halbach array, the rotor iron core is formed by winding a silicon steel sheet or pressing an amorphous material, and the rotor iron core is formed by winding the silicon steel sheet or pressing the amorphous material. The magnetic steel on each axial side of the rotor core is opposite to one stator, and an air gap surface is arranged between the opposite magnetic steel and stator, so that the motor has the characteristics that the sinusoidal property of the air gap flux density waveform of the motor is better, the amplitude of the flux density is high, the thickness of the rotor core is small, the torque density is improved, and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of axial flux motors, and in particular to an axial flux motor. Background Art

[0002] Axial flux motors are also called disc motors. They have the advantages of small axial size, high torque density, high power density and high efficiency, and are widely used in electric vehicles, general industry and other fields. Axial flux motors include stators and rotors, of which the rotor mainly includes the following two structures:

[0003] refer to Figure 1 The rotor includes a magnetic steel body 110' and a retainer 130', and the outer ring of the retainer 130' is clamped with a plurality of magnetic steel bodies 110'. The retainer 130' made of composite materials has the characteristics of light weight and no loss, but the structural strength is low. The retainer 130' made of metal material will generate large eddy current loss and easily cause the magnetic steel to lose magnetism at high temperature.

[0004] refer to Figure 2 The rotor includes two layers of magnetic steel bodies 110' and an iron core 120' in the middle layer. The magnetic steel bodies 110' in the upper and lower layers are surface mounted, and the iron core 120' is usually made of magnetic conductive metal. Although the structural strength is improved, it will produce large eddy current losses and easily cause the magnetic steel to lose magnetism at high temperatures. Usually, the loss is reduced by increasing the thickness, but it will increase the weight of the motor and reduce the power density.

[0005] Furthermore, axial flux motors are developing towards high speed and high power density, which puts forward higher strength and performance requirements for the rotor structure of axial flux motors.

[0006] Based on this, there is an urgent need for an axial flux motor that can reduce eddy current losses while ensuring structural strength. Summary of the invention

[0007] The object of the present invention is to provide an axial flux motor to improve structural strength and reduce eddy current losses.

[0008] In order to achieve the above object, the present invention provides an axial flux motor, comprising:

[0009] Two stators;

[0010] A rotor, comprising a rotor core and magnetic steel, wherein a plurality of magnetic steels are respectively arranged on both axial sides of the rotor core, and the plurality of magnetic steels are arranged in a Halbach array, wherein the magnetic steels on each axial side of the rotor core are opposite to a stator, and an air gap surface is arranged between the opposite magnetic steels and the stator.

[0011] As a preferred embodiment, the rotor core is formed by winding silicon steel sheets or pressing amorphous materials.

[0012] As a preferred embodiment, magnetic steel grooves are respectively opened on both sides of the rotor core in the axial direction, and magnetic steels are arranged in the magnetic steel grooves.

[0013] As a preferred embodiment, the magnetic steel is divided into axial magnetization magnetic steel and tangential magnetization magnetic steel according to the magnetization direction. On each axial side of the rotor core, the axial magnetization magnetic steel and the tangential magnetization magnetic steel are alternately arranged.

[0014] As a preferred embodiment, the magnetic steels on each axial side of the rotor core are arranged circumferentially and connected in sequence.

[0015] As a preferred embodiment, the magnetic steel includes a plurality of magnetic steel units, and the magnetic steel unit includes an axially magnetized magnetic steel and two tangentially magnetized magnetic steels, and the axially magnetized magnetic steel is connected between the two tangentially magnetized magnetic steels.

[0016] As a preferred embodiment, a mounting hole is provided between two adjacent magnetic steels connected in sequence, and the rotor further comprises:

[0017] A magnetic steel fixing shaft passes through the mounting hole and connects the inner ring and the outer ring located radially inside and outside the rotor core.

[0018] As a preferred embodiment, the magnetic steel is fan-shaped, trapezoidal or rectangular.

[0019] As a preferred embodiment, the magnetic steel is radially confined between the inner ring and the outer ring.

[0020] As a preferred embodiment, the rotor further includes:

[0021] The reinforcing ribs penetrate the low magnetic density area of ​​the rotor core and respectively connect the inner ring and the outer ring, and the low magnetic density area of ​​the rotor core corresponds to the center position of the magnetic steel.

[0022] As a preferred embodiment, the rotor further includes:

[0023] The fixed plate comprises an upper plate and a lower plate, wherein the upper plate and the lower plate clamp the reinforcing ribs and are supported on the inner wall of the inner ring.

[0024] Compared with the prior art, this technical solution has the following advantages:

[0025] The Halbach magnetic pole array structure is adopted, which has the characteristics of better sinusoidal property of the motor air gap magnetic density waveform, high magnetic density amplitude, small rotor core thickness, improved torque density, etc. The Halbach magnetic pole array is formed by alternately arranging the axial magnetized magnetic steel and the tangential magnetized magnetic steel in the magnetic steel slot of the rotor core, or the axial magnetized magnetic steel is connected between two tangential magnetized magnetic steels.

[0026] By arranging the reinforcing ribs in the low magnetic flux density area, not only the structural strength of the rotor core is improved, but also when the reinforcing ribs are made of metal, eddy current loss will not occur.

[0027] The magnetic steel is radially limited by the inner ring and the outer ring to prevent the magnetic steel from detaching under high-speed rotation, thereby ensuring the reliability of the structure. The inner ring, the outer ring and the rotor core can be fixed by the reinforcing ribs, thereby increasing the use function of the reinforcing ribs.

[0028] The present invention is further described below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a structural schematic diagram of an existing rotor;

[0030] Figure 2 is another structural schematic diagram of an existing rotor;

[0031] Figure 3 It is a structural schematic diagram of the axial flux motor of the present invention;

[0032] Figure 4 An exploded view of a first embodiment of the rotor of the present invention;

[0033] Figure 5 A schematic diagram of the magnetic field flow direction of the first embodiment of the rotor of the present invention;

[0034] Figure 6 It is a schematic structural diagram of the rotor core in the first embodiment of the rotor of the present invention;

[0035] Figure 7 It is a schematic diagram of forming the rotor core in the first embodiment of the rotor of the present invention;

[0036] Figure 8 This is a schematic diagram of the structure of the outer ring of the first embodiment of the rotor of the invention;

[0037] Fig. 9 It is a schematic structural diagram of the inner ring of the rotor in the first embodiment of the present invention;

[0038] Fig.10 It is a schematic structural diagram of the upper disk in the first embodiment of the rotor of the present invention;

[0039] Fig.11 It is a schematic structural diagram of the lower plate in the first embodiment of the rotor of the present invention;

[0040] Fig.12 It is a schematic structural diagram of the reinforcing ribs in the first embodiment of the rotor of the present invention;

[0041] Fig.13 It is a schematic diagram of the structure of the magnetic steel in the first embodiment of the rotor of the present invention; Fig.14 It is a schematic diagram of the structure of the axially magnetized magnetic steel of the present invention; Fig.15 It is a schematic diagram of the structure of the tangential magnetized magnetic steel of the present invention;

[0042] Fig.16 is an exploded view of a second embodiment of the rotor of the present invention;

[0043] Fig.17 A schematic diagram of magnetic field flow direction of a second embodiment of a rotor according to the present invention;

[0044] Fig.18 It is a schematic structural diagram of a rotor core in a second embodiment of the rotor of the present invention;

[0045] Fig.19 It is a schematic diagram of forming the rotor core in the second embodiment of the rotor of the present invention;

[0046] Fig. 20 It is a schematic diagram of the structure of the magnetic steel in the second embodiment of the rotor described in the present invention.

[0047] In the figure: 100 magnetic steel, 110 axially magnetized magnetic steel, 110a first top surface, 110b first splicing surface, 110d1 first inner end surface, 110d2 first outer end surface, 110e first bottom surface, 111a upper limit inclined surface, 111b lower limit inclined surface, 120 second magnetic steel, 120a second top surface, 120b second splicing surface, 120c second fixed surface, 120d1 second inner end surface, 120d2 second outer end surface, 120e second bottom surface, 121a upper limit convex shoulder, 121b lower limit convex shoulder, 122 groove, 100a chamfered portion, 200 magnetic steel fixed shaft, 300 inner ring, 310 inner through hole, 320 inner Connecting hole, 400 outer ring, 410 outer through hole, 420 outer connecting hole, 500 rotor core, 500a low magnetic density area, 500b high magnetic density area, 500c silicon steel sheet, 510 magnetic steel slot, 510c slot portion, 511 slot oblique portion, 520 core through hole, 520c through hole portion, 530 tooth portion, 600 reinforcing rib, 610 rod portion, 620 outer limiting portion, 630 inner limiting portion, 700 fixed plate, 710 upper plate, 711 upper abutting surface, 711a block, 720 lower plate, 721 lower abutting surface, 721a lower accommodating groove, 800 bolts, 1000 mounting hole, 2100 rotor, 2200 stator, 2300 air gap surface. DETAILED DESCRIPTION

[0048] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art can think of other obvious variations. The basic principles of the present invention defined in the following description can be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not deviate from the spirit and scope of the present invention.

[0049] First embodiment

[0050] like Figures 3 to 5 As shown, the axial flux motor comprises:

[0051] Two stators 2200;

[0052] A rotor 2100, the rotor 2100 includes a rotor core 500 and a magnet 100, a plurality of magnets 100 are respectively provided on both axial sides of the rotor core 500, the plurality of magnets 100 are arranged in a Halbach array, the magnet 500 on each axial side of the rotor core 500 is opposite to a stator, and an air gap surface 2300 is provided between the opposite magnets 100 and the stator 2200.

[0053] The Halbach magnetic pole array structure is adopted, which has the characteristics of better sinusoidal air gap magnetic flux waveform, high magnetic flux amplitude, small rotor core thickness, improved torque density, etc. The rotor 2100 is located between the two stators 2200, and an air gap surface 2300 is provided between the rotor 2100 and the stator 2200 on each side to form a dual-stator single-rotor axial flux motor.

[0054] The rotor core 500 is formed by winding silicon steel sheets or by pressing amorphous materials, wherein the rotor core 500 can be formed by winding silicon steel sheets 500c to reduce eddy current loss.

[0055] like Figure 4 As shown, the rotor 2100 further includes:

[0056] An inner ring 300, wherein the inner ring 300 is arranged radially inward of the rotor core 500;

[0057] An outer ring 400, wherein the outer ring 400 is arranged radially outside the rotor core 500, so that the magnetic steel 100 is radially limited between the inner ring 300 and the outer ring 400;

[0058] The reinforcing rib 600 penetrates the low magnetic flux density region 500 a of the rotor core 500 and connects the inner ring 300 and the outer ring 400 .

[0059] The magnetic steel 100 can be arranged on the rotor core 500 in a surface-mounted manner, and the magnetic steel 100 is respectively arranged on both axial sides of the rotor core 500 to correspond to the axial flux motor with double stators and a single rotor. The two axial sides of the rotor core 500 are respectively close to the stator and the rotor to form an air gap surface, that is, a magnetic circuit is formed on both axial sides of the rotor core 500. The middle position of the rotor core 500 in the axial direction is a low magnetic density area 500a. By arranging the reinforcing ribs 600 in the low magnetic density area 500a, not only the structural strength of the rotor core 500 is improved, but also when the reinforcing ribs 600 are made of metal, eddy current loss will not occur. The magnetic steel 100 is radially limited by the inner ring 300 and the outer ring 400 to prevent the magnetic steel 100 from detaching under high-speed rotation, thereby ensuring the reliability of the structure. The inner ring 300, the outer ring 400 and the rotor core 500 can be fixed by the reinforcing ribs 600, thereby increasing the use function of the reinforcing ribs 600.

[0060] refer to Figure 5The low magnetic flux density zone 500a of the rotor core 500 corresponds to the center position of the magnetic steel 100. Specifically, the low magnetic flux density zone 500a is located in the middle position of the axial direction of the rotor core 500 and corresponds to the center of the axially magnetized magnetic steel 110. The magnetic flux density of the low magnetic flux density zone 500a of the rotor core 500 is 0 to 0.8T.

[0061] The high magnetic flux density area 500 b of the rotor core 500 corresponds to a position between the axial magnetization magnetic steel 110 and the tangential magnetization magnetic steel 120 , and the magnetic flux density of the high magnetic flux density area 500 b of the rotor core 500 is 1.8-2.5T.

[0062] The magnetic flux density of the rotor core 500 gradually increases from the low magnetic flux density area 500a to the adjacent high magnetic flux density area 500b. Figure 5 , in the process of splicing two adjacent magnetic steels 100, two tangentially magnetized magnetic steels 120 are arranged between the axially magnetized magnetic steels 110 of the two magnetic steels 100, wherein the junction of the tangentially magnetized magnetic steels 120 and the axially magnetized magnetic steels 110 corresponds to the rotor core 500 which is a high magnetic density area 500b, and the magnetic density of the rotor core 500 gradually decreases from the high magnetic density area 500b to the splicing of the two tangentially magnetized magnetic steels 120. It should be noted that the magnetic density of the rotor core 500 corresponding to the splicing of the two tangentially magnetized magnetic steels 120 is greater than the magnetic density of the low magnetic density area 500a. The magnetic density, also known as the magnetic flux density, refers to the number of magnetic lines of force passing vertically through a unit area.

[0063] like Figure 6 As shown, the rotor core 500 is disc-shaped, and the rotor core 500 is provided with a core through-hole 520 through which the reinforcing rib 600 passes. The core through-hole 520 is located in the middle of the axial direction of the rotor core 500, that is, in the low magnetic density area 500a. The core through-hole 520 can penetrate the radial inner side and the radial outer side of the rotor core 500, so that the reinforcing rib 600 passes through the rotor core 500 in the radial direction.

[0064] The rotor core 500 may be formed by winding silicon steel sheets 500c to reduce eddy current loss. Figure 6 and Figure 7 , the through hole portion 520c of the core through hole 520 can be firstly punched out of the silicon steel sheet 500c, and then the silicon steel sheet 500c is wound to form the rotor core 500, so that the through hole portions 520c on the same straight line on each layer of the silicon steel sheet 500c form the core through hole 520. Of course, the rotor core 500 is pressed from amorphous material, and the amorphous material includes soft magnetic material.

[0065] like Figure 4 and Fig.13 As shown, on each axial side of the rotor core 500, the magnetic steels 100 are spliced ​​in the circumferential direction, and a mounting hole 1000 is formed between two adjacent magnetic steels 100. The rotor further includes:

[0066] The magnetic steel fixing shaft 200 passes through the mounting hole 1000 and is respectively connected to the inner ring 300 and the outer ring 400 to limit the rotor core 500 in the circumferential direction and the axial direction.

[0067] Since the magnetic steel fixing shaft 200 is built inside the magnetic steel 100 and is located in the magnetic circuit area, the magnetic steel fixing shaft 200 adopts a screw made of a non-magnetic metal material to avoid the increase of eddy current loss.

[0068] refer to Figure 8 and Fig. 9 The inner ring 300 is provided with an inner connection hole 320, and the outer ring 400 is provided with an outer connection hole 420. The magnetic steel fixing shaft 200 passes through the outer connection hole 420 on the outer ring 400 and the mounting hole 1000, and is screwed with the inner connection hole 320 to achieve the fixation of the three.

[0069] like Figure 3 , Figures 13 to 15 As shown, the magnetic steel 100 includes a plurality of magnetic steel units 1001, and the magnetic steel units 1001:

[0070] An axially magnetized magnetic steel 110, wherein the surface of the axially magnetized magnetic steel 110 comprises a first top surface 110a, a first bottom surface 110e and a first joint surface 110b, wherein the first joint surface 110b is connected between the first top surface 110a and the first bottom surface 110e, and the first top surface 110a and the first bottom surface 110e define the axial dimension of the axially magnetized magnetic steel 110, and the magnetization direction of the axially magnetized magnetic steel 110 is the axial direction;

[0071] A tangentially magnetized magnetic steel 120, wherein the surface of the tangentially magnetized magnetic steel 120 comprises a second top surface 120a, a second bottom surface 120e, a second splicing surface 120b and a second fixing surface 120c, wherein the second splicing surface 120b and the second fixing surface 120c are opposite to each other and are respectively connected between the second top surface 120a and the second bottom surface 120e, wherein the second splicing surface 120b is spliced ​​with the first splicing surface 110b of the axially magnetized magnetic steel 110, and the first splicing surface 110b is embedded in the second splicing surface 120b, and the second fixing surface 120c is used for installing a magnetic steel fixing shaft 200, wherein the axially magnetized magnetic steel 110, the tangentially magnetized magnetic steel 120 and the magnetic steel fixing shaft 200 are arranged in a circumferential direction, and the magnetizing direction of the tangentially magnetized magnetic steel 120 is a tangential direction of the circumferential direction.

[0072] Since the axial magnetized magnetic steel 110 and the tangential magnetized magnetic steel 120 have certain magnetic force and magnetic field after magnetization, the overall magnetic force and magnetic field effect are increased when the axial magnetized magnetic steel 110 and the tangential magnetized magnetic steel 120 are spliced ​​into the magnetic pole assembly 100. The tangential magnetized magnetic steel 120 is fixed by installing the magnetic steel fixing shaft 200 on the second fixing surface 120c of the tangential magnetized magnetic steel 120. At the same time, when the axial magnetized magnetic steel 110 and the tangential magnetized magnetic steel 120 are spliced, the first splicing surface 110b is embedded in the second splicing surface 120b, so that the two are axially limited to each other, thereby improving the installation strength of the magnetic pole assembly 100 and improving the stability of the structure.

[0073] The first top surface 110a and the first bottom surface 110e define the axial dimension of the axial magnetized magnetic steel 110. The first top surface 110a is disposed toward the stator 2000, and the first bottom surface 110e is used to connect the iron core 500. The magnetizing direction of the axial magnetized magnetic steel 110 is the axial direction, that is, the magnetizing direction of the axial magnetized magnetic steel 110 is perpendicular to the first top surface 110a and the first bottom surface 110e, respectively, wherein the magnetizing direction of the axial magnetized magnetic steel 110 is the direction from the first top surface 110a to the first bottom surface 110e along the axial direction, or the magnetizing direction of the axial magnetized magnetic steel 110 is the direction from the first bottom surface 110e to the first top surface 110a along the axial direction.

[0074] The second top surface 120a is disposed toward the stator 2000, and the second bottom surface 120e is connected to the iron core 500. When the tangential magnetized magnetic steel 120 and the axial magnetized magnetic steel 110 are spliced, the second top surface 120a is flush with the first top surface 110a, and the second bottom surface 120e is flush with the first bottom surface 110e.

[0075] The axial magnetized magnetic steel 110, the tangential magnetized magnetic steel 120 and the magnetic steel fixing shaft 200 are arranged along the circumferential direction, and the magnetizing direction of the tangential magnetized magnetic steel 120 is the tangential direction of the circumferential direction (hereinafter referred to as the tangential direction), that is, the magnetizing direction of the tangential magnetized magnetic steel 120 is the direction from the second splicing surface 120b to the second fixing surface 120c along the tangent direction, or the magnetizing direction of the second magnetic steel 120 is the direction from the second fixing surface 120c to the second splicing surface 120b along the tangent direction.

[0076] like Figures 13 to 15As shown, an upper limit inclined surface 111a is provided between the first joint surface 110b and the first top surface 110a, and an upper limit boss 121a is provided between the second joint surface 120b and the second top surface 120a, and the upper limit boss 121a abuts against the upper limit inclined surface 111a, so that the axially magnetized magnetic steel 110 is pressed between the upper limit boss 121a of the tangentially magnetized magnetic steel 120 and the iron core 500, preventing the axially magnetized magnetic steel 110 from axial displacement.

[0077] A lower limit inclined surface 111b is provided between the first joint surface 110b and the first bottom surface 110e, and a lower limit convex shoulder 121b is provided between the second joint surface 120b and the second bottom surface 120e, and the lower limit inclined surface 111b abuts against the lower limit convex shoulder 121b. In this way, not only the axial limit capability of the axial magnetized magnetic steel 110 is improved, but also the lower limit convex shoulder 121b of the tangential magnetized magnetic steel 120 is abutted under the lower limit inclined surface 111b, so as to axially limit the tangential magnetized magnetic steel 120.

[0078] It can be seen that the first joint surface 110b is embedded between the upper limit boss 121a and the lower limit boss 121b on the upper and lower sides of the second joint surface 120b, and the axially magnetized magnetic steel 110 and the tangentially magnetized magnetic steel 120 can axially limit each other, thereby improving the stability of the structure.

[0079] like Fig.13 and Fig.14 As shown, the surface of the axially magnetized magnetic steel 110 further includes a first inner end face 110d1 and a first outer end face 110d2, the radial dimension of the axially magnetized magnetic steel 110 is defined between the first inner end face 110d1 and the first outer end face 110d2, and the first inner end face 110d1 and the first outer end face 110d2 are respectively connected between the two first splicing faces 110b of the axially magnetized magnetic steel 110, and the distance between the two first splicing faces 110b increases radially from the first inner end face 110d1 to the first outer end face 110d2, that is, the axially magnetized magnetic steel 110 is fan-shaped.

[0080] like Fig.13 and Fig.15 As shown, the surface of the tangentially magnetized magnetic steel 120 also includes a second inner end face 120d1 and a second outer end face 120d2, the radial dimension of the tangentially magnetized magnetic steel 120 is defined between the second inner end face 120d1 and the second outer end face 120d2, and they are respectively connected between the second splicing face 120b and the second fixed face 120c, the distance between the second splicing face 120b and the second fixed face 120c increases radially from the second inner end face 120d1 to the second outer end face 120d2, that is, the tangentially magnetized magnetic steel 120 is fan-shaped.

[0081] Since the axial magnetized magnetic steel 110 and the tangential magnetized magnetic steel 120 are both fan-shaped, the magnetic pole assembly 100 formed by splicing the two is also fan-shaped. At this time, the first inner end face 110d1 and the second inner end face 120d1 are flush, and the first outer end face 110d2 and the second outer end face 120d2 are flush. The first inner end face 110d1 and the first outer end face 110d2 are both planes. Of course, the first inner end face 110d1 can be a concave surface, and the first outer end face 110d2 is a convex surface. Similarly, the second inner end face 120d1 and the second outer end face 120d2 are both planes, or the second inner end face 120d1 is a concave surface, and the second outer end face 120d2 is a convex surface.

[0082] like Figure 4 , Figures 13 to 15 As shown, a groove 122 for mounting the magnetic steel fixing shaft 200 is provided on the second fixing surface 120c, and the groove 122 radially penetrates the tangentially magnetized magnetic steel 120, so that the tangentially magnetized magnetic steel 120 can be axially limited. At the same time, the tangentially magnetized magnetic steel 120 is circumferentially limited between the axially magnetized magnetic steel 110 and the magnetic steel fixing shaft 200.

[0083] like Figure 4 and Figure 5 As shown, the number of the tangential magnetized magnetic steels 120 of the magnetic pole assembly 100 can be two, and they are arranged on both sides of the circumference of the axial magnetized magnetic steel 110. In this case, the number of the first splicing surfaces 110b is two, and the two first splicing surfaces 110b are located on both sides of the circumference of the axial magnetized magnetic steel 110. Each first splicing surface 110b is spliced ​​with a second splicing surface 120b of a tangential magnetized magnetic steel 120. Figure 3 As shown, in two adjacent magnetic pole assemblies 100, the magnetizing direction of the axial magnetizing magnetic steel 110 of one magnetic pole assembly 100 is along the axial direction from the first bottom surface 110e to the first top surface 110a, and the magnetizing direction of the tangential magnetizing magnetic steel 120 is along the tangential direction from the second fixing surface 120c to the second splicing surface 120b. Specifically, the magnetizing direction of the tangential magnetizing magnetic steel 120 located on the left side of the axial magnetizing magnetic steel 110 is from left to right, and the magnetizing direction of the tangential magnetizing magnetic steel 120 located on the right side of the axial magnetizing magnetic steel 110 is from right to left. The magnetizing direction of the axial magnetizing magnetic steel 110 of another magnetic pole assembly 100 is from the first top surface 110a to the first bottom surface 110e along the circumferential direction, and the magnetizing direction of the tangential magnetizing magnetic steel 120 is tangential and from the second splicing surface 120b to the second fixing surface 120c, wherein the magnetizing direction of the tangential magnetizing magnetic steel 120 located on the left side of the axial magnetizing magnetic steel 110 is from right to left, and the magnetizing direction of the tangential magnetizing magnetic steel 120 located on the right side of the axial magnetizing magnetic steel 110 is from left to right.

[0084] The Halbach magnetic pole array obtained as above has the characteristics of better sinusoidality of the motor air gap magnetic flux waveform, high magnetic flux amplitude, small rotor core thickness, and improved torque density.

[0085] like Figure 4 , Figure 8 and Fig. 9 As shown, the inner ring 300 and the outer ring 400 can be made of steel to improve the structural strength. The height of the inner ring 300 and the outer ring 400 are equal, and are equal to the sum of the heights of the rotor core 500 and the upper and lower layers of the magnetic steel 100, ensuring the radial limiting ability of the inner ring 300 and the outer ring 400 to the magnetic steel 100.

[0086] refer to Figure 8 and Fig. 9 , the inner ring 300 is provided with an inner through hole 310, the outer ring 400 is provided with an outer through hole 410, and the inner through hole 310 and the outer through hole 410 are used for the reinforcing rib 600 to pass through. It can be seen that the cross-sectional shapes of the core through hole 520 of the rotor core 500, the inner through hole 310 of the inner ring 300, the outer through hole 410 of the outer ring 400, and the rod 610 of the reinforcing rib 600 are adapted to each other, for example, in a square or circular shape, and the size, shape, and size can be designed according to electromagnetic simulation and structural strength.

[0087] like Figure 4 , Figures 10 to 12 As shown, the rotor also includes:

[0088] The fixed plate 700 is supported on the inner wall of the inner ring 300 . The fixed plate 700 includes an upper plate 710 and a lower plate 720 . The reinforcing rib 600 is clamped between the upper plate 710 and the lower plate 720 .

[0089] The fixing plate 700 can not only fix the reinforcing rib 600 , but also enhance the supporting force to the inner ring 300 , thereby further ensuring the structural strength.

[0090] refer to Fig.10 , the reinforcing rib 600 comprises:

[0091] The outer limit portion 620,

[0092] Inner limit portion 630;

[0093] The rod portion 610 has the outer limiting portion 620 and the inner limiting portion 630 respectively disposed at both ends of the rod portion 610. The rod portion 610 passes through the outer ring 400, the low magnetic density area 500a of the rotor core 500 and the inner ring 300. The outer limiting portion 620 abuts against the outer wall of the outer ring 400, and the inner limiting portion 630 is clamped with the fixed disk 700.

[0094] The outer limiting portion 620 is configured as an arc-shaped plate and abuts against the outer wall of the outer ring 400 , and the inner limiting portion 630 is configured as a slot, which is opened on the rod portion 610 and is engaged with the fixing plate 700 to fix the reinforcing rib 600 .

[0095] Specifically, the axial upper side surface of the lower plate 720 is a lower abutting surface 721, and a lower accommodating groove 721a is provided on the lower abutting surface 721; the axial lower side surface of the upper plate 710 is an upper abutting surface 711, and a clamping block 711a is provided on the upper abutting surface 711, and the clamping block 711a corresponds to the lower accommodating groove 721a one by one; the lower abutting surface 721 of the lower plate 720 and the upper abutting surface 711 of the upper plate 710 abut against each other, and after clamping the reinforcing rib 600, the rod portion 610 of the reinforcing rib 600 is located in the lower accommodating groove 721a, and the inner limit portion 630 of the reinforcing rib 600 is clamped with the clamping block 711a.

[0096] The lower receiving groove 721a passes through the outer edge of the lower plate 720. When the upper plate 710 and the lower plate 720 are axially spliced, the clamping block 711a can fall into the lower receiving groove 721a, so that the clamping block 711a can be clamped with the reinforcing rib 600 located in the lower receiving groove 721a, that is, the clamping block 711a is clamped with the clamping groove of the rod 610. Afterwards, the upper plate 710 and the lower plate 720 can be fixed by bolts 800, etc., which is convenient and quick to fix.

[0097] refer to Figure 4 The number of the magnetic steel fixing shaft 200, the reinforcing ribs 600 and the bolts 800 are all multiple, and can be selected based on factors such as structural strength. Among them, the bolts 800 fixed between the upper plate 710 and the lower plate 720 are staggered with the lower accommodating groove 721a.

[0098] When assembling the axial flux motor rotor, the magnetic steel 100 can be first arranged on both axial sides of the rotor core 500, and then the inner ring 300 and the outer ring 400 can be arranged radially inside and outside the rotor core 500, so that the magnetic steel 100 is radially limited between the inner ring 300 and the outer ring 400, and then the magnetic steel fixing shaft 200 is sequentially passed through the outer ring 400, the mounting hole 1000 between the magnetic steel 100, and the inner ring 300 to achieve fixation, and the reinforcing rib 600 is sequentially passed through the outer ring 400 and the rotor core 500 until the tail of the reinforcing rib 600 passes through the inner ring 300, and then the tail of the reinforcing rib 600 is clamped and fixed by the upper plate 710 and the lower plate 720 of the fixing plate 700 to complete the assembly of the axial flux motor rotor.

[0099] Second embodiment

[0100] like Fig.16 As shown, the axial flux motor of the second embodiment is different from the first embodiment in that magnetic steel slots 510 are respectively opened on both sides of the axial direction of the rotor core 500, and the magnetic steel 100 is arranged in the magnetic steel slots 510.

[0101] like Fig.18 and Fig.19 As shown, the rotor core 500 can be formed by winding silicon steel sheets 500c to reduce eddy current loss. The through hole portion 520c of the core through hole 520 and the slot portion 510c of the magnetic steel slot 510 can be firstly punched out of the silicon steel sheet 500c, the through hole portion 520c is located in the middle of the width of the silicon steel sheet 500c, and the slot portions 510c are respectively arranged on both sides of the width of the silicon steel sheet 500c, and then the silicon steel sheet 500c is wound to form the rotor core 500, so that the through hole portions 520c on each layer of the silicon steel sheet 500c and located on the same straight line form the core through hole 520, and the slot portions 510c located on the same straight line form the magnetic steel slot 510.

[0102] refer to Figures 16 to 20 The magnetic steel slot 510 penetrates the radial inner side and the radial outer side of the rotor core 500, so that the magnetic steel 100 can be inserted into the magnetic steel slot 510 in the radial direction. The magnetic steel slot 510 is consistent with the cross section of the magnetic steel 100, for example, it is rectangular. The magnetic steel 100 with a rectangular cross section is easy to process, which improves the material utilization rate and reduces the amount of magnetic steel to reduce costs. The shape of the magnetic steel slot 510 can also be made into a desired shape according to electromagnetic needs, and different processing methods can be used, such as winding first and then cutting to form the magnetic steel slot 510.

[0103] The magnetic steel slot 510 is provided with a slot bevel portion 511 near the axial side of the rotor core 500 , and the magnetic steel 100 is provided with a chamfered portion 100 a adapted to the slot bevel portion 511 to prevent the magnetic steel 100 from axial displacement.

[0104] like Fig.18 The magnetic steel slots 510 on both axial sides of the rotor core 500 correspond one to one, and the core through holes 520 are located between the corresponding magnetic steel slots 510. After the reinforcing ribs 600 are inserted into the core through holes 520, the structural strength can be guaranteed after the magnetic steel slots 510 are opened on both axial sides of the rotor core 500.

[0105] like Fig.17 As shown, the magnetic steel 100 is divided into tangential magnetized magnetic steel and axial magnetized magnetic steel, the tangential magnetized magnetic steel and the axial magnetized magnetic steel are arranged at intervals, the magnetizing direction of the axial magnetized magnetic steel 110 is axial, and is also divided into upward or downward, and the magnetizing direction of the tangential magnetized magnetic steel 120 is tangential, and is also divided into left or right. For details, please refer to Fig.17 , and then realize the Halbach magnetic pole array.

[0106] refer to Fig.18 , a tooth portion 530 is provided on each axial side of the rotor core 500 and between two adjacent magnetic steel slots 510, and the width of the tooth portion 530 increases radially from the inside to the outside, that is, the width of the tooth portion 530 is narrower near the radial inside and is easy to saturate. For this reason, the tangential magnetized magnetic steel can use a magnetic steel with low remanence, and the remanence of the entire tangential magnetized magnetic steel gradually increases radially from the inside to the outside, which can further reduce the cost of the magnetic steel. Remanence refers to the magnetism that still exists in a magnetic field or electromagnetic system after the external magnetic field or current excitation is removed.

[0107] In summary, by arranging the reinforcing ribs 600 in the low magnetic flux density area 500a, not only the structural strength of the rotor core 500 is improved, but also eddy current loss will not occur when the reinforcing ribs 600 are made of metal. The magnetic steel 100 is radially limited by the inner ring 300 and the outer ring 400 to prevent the magnetic steel 100 from detaching under high-speed rotation, thereby ensuring the reliability of the structure. The inner ring 300, the outer ring 400 and the rotor core 500 can be fixed by the reinforcing ribs 600, thereby increasing the use function of the reinforcing ribs 600. The Halbach magnetic pole array structure is adopted, which has the characteristics of better sinusoidal properties of the motor air gap magnetic flux waveform, high magnetic flux amplitude, small rotor core thickness, and improved torque density.

[0108] The embodiments described above are only used to illustrate the technical ideas and features of the present invention, and their purpose is to enable technicians in this field to understand the contents of the present invention and implement them accordingly. The patent scope of the present invention cannot be limited only by this embodiment, that is, any equivalent changes or modifications made according to the spirit disclosed by the present invention still fall within the patent scope of the present invention.

Claims

1. An axial flux motor, It is characterized in that include: Two stators (2200); A rotor (2100) is provided, wherein the rotor (2100) comprises a rotor core (500) and magnetic steel (100), a plurality of magnetic steels (100) are respectively arranged on two axial sides of the rotor core (500), the plurality of magnetic steels (100) are arranged in a Halbach array, the magnetic steels (500) on each axial side of the rotor core (500) are opposite to a stator (2200), and an air gap surface (2300) is provided between the opposite magnetic steels (100) and the stator (2200).

2. The axial flux motor according to claim 1, It is characterized in that The rotor core (500) is formed by winding silicon steel sheets or by pressing amorphous materials.

3. The axial flux motor according to claim 1, It is characterized in that Magnetic steel grooves (510) are respectively provided on two axial sides of the rotor core (500), and magnetic steel (100) is arranged in the magnetic steel grooves (510).

4. The axial flux motor according to claim 2, It is characterized in that The magnetic steel (100) is divided into axial magnetization magnetic steel (110) and tangential magnetization magnetic steel (120) according to the magnetization direction. On each axial side of the rotor core (500), the axial magnetization magnetic steel (110) and the tangential magnetization magnetic steel (120) are alternately arranged.

5. The axial flux motor according to claim 1, It is characterized in that The magnetic steels (100) on each axial side of the rotor core (500) are arranged in a circumferential direction and are connected in sequence.

6. The axial flux motor according to claim 5, It is characterized in that The magnetic steel (100) comprises a plurality of magnetic steel units (1001), wherein the magnetic steel unit (1001) comprises an axially magnetized magnetic steel (110) and two tangentially magnetized magnetic steels (120), wherein the axially magnetized magnetic steel (110) is connected between the two tangentially magnetized magnetic steels (120).

7. The axial flux motor according to claim 5, It is characterized in that A mounting hole (1000) is provided between two adjacent magnetic steels (100) that are connected in sequence, and the rotor (2100) further comprises: A magnetic steel fixed shaft (200), wherein the magnetic steel fixed shaft (200) passes through the mounting hole (1000) and connects the inner ring (300) and the outer ring (400) located radially inside and outside the rotor core (500).

8. An axial flux motor according to any one of claims 1 to 7, Features The magnetic steel (100) is radially limited between the inner ring (300) and the outer ring (400).

9. The axial flux motor according to claim 8, It is characterized in that The rotor (2100) further comprises: The reinforcing rib (600) passes through the low magnetic density area (500a) of the rotor core (500) and respectively connects the inner ring (300) and the outer ring (400), and the low magnetic density area (500a) of the rotor core (500) corresponds to the center position of the magnetic steel (100).

10. The axial flux electric machine according to claim 9, It is characterized in that The rotor (2100) further comprises: A fixed plate (700), the fixed plate (700) comprising an upper plate (710) and a lower plate (720), the upper plate (710) and the lower plate (720) clamping the reinforcing rib (600) and supported on the inner wall of the inner ring (300).

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