Axial flux motor

Abstract

The invention discloses an axial magnetic flux motor which comprises a rotor assembly and a cooling assembly. The cooling assembly is arranged between the two rotor discs of the rotor assembly in the axial direction; a cooling air channel penetrating in the radial direction is formed in the cooling assembly, rotor air channels penetrating in the radial direction are formed in the sides, facing the cooling assembly, of the two rotor discs, and the cooling air channel is correspondingly communicated with the rotor air channels arranged on the two sides in the axial direction to form two circulating air channels. And high-temperature airflow in the rotor air duct and cooling airflow in the cooling air duct realize continuous convection and circulating heat exchange through the circulating air duct. Through a double-air-path circulating cooling structure, the rotor assembly is subjected to air-cooling heat dissipation, heat generated in the operation process of the rotor assembly is efficiently taken away, the working temperature of the rotor assembly is reduced, the risk of permanent magnet demagnetization caused by high temperature can be restrained, the stability of the output torque of the motor and continuous improvement of the operation efficiency are ensured, and the service life of the motor is prolonged. And the problem of performance degradation caused by temperature rise is avoided, so that the working reliability of the axial magnetic flux motor is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electric machines, in particular to an axial flux motor. BACKGROUND

[0002] Axial flux motors have the advantages of high power density, compact structure and lightweight, and are widely used in electric vehicles, aerospace and wind power generation fields. According to the different magnetic circuit structures, axial flux motors are mainly divided into two categories: yoke type and yokeless type. Among them, the yokeless structure cancels the yoke part of the stator core. Although this design can achieve lightweight and high power density at the same time, it also cuts off the axial heat dissipation path provided by the traditional yoke part, which makes the heat generated during operation easily accumulate on the stator side and difficult to be dissipated. If the heat cannot be dissipated in time, it will affect the normal operation of the yokeless axial flux motor, and in severe cases, it will also cause coil insulation damage, permanent magnet demagnetization at high temperature and other failures.

[0003] For the heat dissipation problem of the yokeless axial flux motor, the prior art usually only sets a cooling assembly on the stator side. However, since the rotor is in a continuous high-speed rotating state, it is difficult to introduce effective cooling measures, resulting in a blind area for heat dissipation on the rotor side, which leads to uneven cooling. The temperature of the rotor permanent magnet will continue to rise during operation, which will directly cause the reduction of motor output torque and operating efficiency. In severe cases, once the temperature of the permanent magnet exceeds its material temperature limit, irreversible demagnetization will occur, causing permanent damage to the motor and seriously affecting the working reliability of the whole machine. SUMMARY

[0004] Therefore, the purpose of the present application is to provide an axial flux motor, which adds a cooling assembly between the two rotor discs of the rotor assembly, forms a double air path circulating cooling structure, and cools the rotor assembly by air cooling to avoid performance degradation caused by temperature rise, and improves the working reliability of the axial flux motor, solving the technical problem of low working reliability of the existing axial flux motor due to lack of effective cooling.

[0005] To achieve the above purpose, the present application provides an axial flux motor, which comprises a rotor assembly and a cooling assembly; the cooling assembly is arranged between the two rotor discs of the rotor assembly along the axial direction;

[0006] The cooling assembly is internally provided with a cooling air duct penetrating along the radial direction, and the side of the two rotor discs facing the cooling assembly is formed with a rotor air duct penetrating along the radial direction, and the cooling air duct and the rotor air duct arranged on both sides are respectively connected in correspondence along the axial direction, forming two circulating air ducts;

[0007] The high-temperature gas flow in the rotor air duct and the cooling gas flow in the cooling air duct are circulated and heat-exchanged through the circulating air duct.

[0008] In some embodiments, the cooling assembly further comprises an inner support ring, an outer support ring and a rotor support, the cooling assembly is fixed between the inner support ring and the outer support ring, the inner side wall of the outer support ring is provided with an outer flange ring fixed with the cooling assembly, the outer flange ring is provided with an axial through hole, and the side wall of the inner support ring is provided with a radial through hole;

[0009] The rotor support is coaxially arranged in the inner support ring, two ends of the rotor support are fixed with the two rotor discs respectively, and the outer side of the rotor support is provided with an annular protrusion, and two independent axial air ducts are formed on two sides of the annular protrusion;

[0010] One end of each group of rotor air ducts is connected with the cooling air duct through the axial through hole, and the other end is connected with the cooling air duct through one of the axial air ducts and the radial through hole, to form a circulating air duct.

[0011] In some embodiments, the stator assembly further comprises a plurality of groups of stator modules, all the stator modules and all the cooling modules of the cooling assembly are arranged in the circumferential direction alternately, and the pressing strip of the cooling module and the clamping groove of the stator module are matched in the circumferential direction.

[0012] Each group of stator modules comprises a stator core, a plurality of groups of stator windings wound on the stator core, and a liquid cooling sleeve pipe sleeved on the stator core, the liquid cooling sleeve pipe is arranged between the adjacent two groups of stator windings, and the liquid cooling sleeve pipe exchanges heat with the stator core and the stator winding through the cooling liquid respectively.

[0013] In some embodiments, the cooling assembly comprises a plurality of groups of cooling modules, each group of cooling modules comprises an inner cooling core and an outer fixed block fixed between the adjacent two groups of stator modules, the inner part of the outer fixed block forms a cooling air duct, and the inner cooling core is fixed in the cooling air duct.

[0014] The inner cooling core comprises a liquid cooling block, a plurality of heat-conducting rods and two support plates fixed at two ends of the heat-conducting rods respectively, the liquid cooling block is provided with a liquid collecting cavity, all the heat-conducting rods pass through the liquid collecting cavity and extend into the cooling air duct, the hot air in the cooling air duct exchanges heat with the cooling liquid in the liquid cooling block through the heat-conducting rods, and the two support plates are attached to the two side walls of the cooling air duct respectively.

[0015] In some embodiments, the side of the outer fixed block facing the stator module is provided with a heat-conducting layer, and the adjacent cooling module and the stator module exchange heat through the heat-conducting layer.

[0016] The liquid cooling block of the cooling module and the liquid cooling sleeve pipe of the adjacent stator module are connected through a liquid cooling pipe.

[0017] In some embodiments, the outer fixed block comprises two inclined plates arranged at an angle and two parallel pressing plates, the side of each of the two inclined plates facing the stator module is provided with a receiving groove, and the receiving groove is provided with a heat-conducting layer.

[0018] Two pressing plates are respectively fixed on both ends of the inclined plate, and the portions of each pressing plate beyond the inclined plate are formed with pressing strips extending in the circumferential direction; the end portion of the stator core is provided with a protruding ridge extending in the circumferential direction, and the protruding ridge and the end face of the adjacent stator winding form a clamping groove in cooperation.

[0019] In some embodiments, a partition plate is fixed in the liquid collecting cavity, and the partition plate is used to separate the liquid collecting cavity into a liquid inlet cavity and a liquid outlet cavity.

[0020] The liquid cooling block comprises an inner cover plate and an outer cover plate, the inner cover plate is arranged at the air outlet of the cooling air duct, and the outer cover plate is arranged at the air inlet of the cooling air duct; the outer cover plate is provided with a liquid inlet pipe and a liquid outlet pipe, the liquid inlet pipe is connected with the liquid inlet cavity, and the liquid outlet pipe is connected with the liquid outlet cavity.

[0021] The partition plate is vertically connected with the outer cover plate, and a gap is formed between the partition plate and the inner cover plate, and the gap communicates the liquid inlet cavity and the liquid outlet cavity.

[0022] In some embodiments, the rotor support comprises an inner ring and an outer ring coaxially arranged on the outer periphery of the inner ring; the end portion of the outer ring is protruding and formed with two fixing flanges, and the two fixing flanges are respectively fixedly connected with the two rotor discs;

[0023] An annular groove is formed between the two fixing flanges, and an annular protrusion is protrudingly formed in the annular groove, and the annular protrusion separates the annular groove into two axial air ducts;

[0024] The end face of the fixing flange is in contact with the hole of the central hole of the connected rotor disc, and the inner diameter of the outer ring is equal to the inner diameter of the central hole of the two rotor discs.

[0025] In some embodiments, the rotor support further comprises a connecting ring fixedly connected between the inner ring and the outer ring; the length of the inner ring is less than the length of the outer ring, and the inner side wall of the inner ring is provided with an inner side ring groove;

[0026] The connecting ring comprises a first ring body and a second ring body respectively fixedly connected with the two ends of the inner ring, and the first ring body and the second ring body are both provided with weight-reducing holes.

[0027] In some embodiments, it further comprises a rotating shaft and two end covers respectively sleeved on both ends of the rotating shaft, and the two end covers are respectively fixedly arranged on both ends of the outer support ring;

[0028] A bearing assembly is arranged between the rotating shaft and the end cover, and the bearing assembly comprises a bearing and an inner shaft sleeve and an outer shaft sleeve respectively arranged at both ends of the bearing, both of which are sleeved on the rotating shaft, and a cover is arranged between the outer shaft sleeve and the rotating shaft;

[0029] The inner ring of the bearing is in contact with the shaft shoulder arranged on the cover and the rotating shaft in the axial direction, and the outer ring of the bearing is in contact with the outer protruding ring of the outer shaft sleeve and the inner protruding ring of the inner shaft sleeve in the axial direction.

[0030] Compared with the prior art, the present invention optimizes the structure of the axial flux motor. The optimized axial flux motor includes a rotor assembly and a cooling assembly. The cooling assembly is located between the two rotor disks of the rotor assembly. The cooling assembly has a radially penetrating cooling air duct inside. Both rotor disks have radially penetrating rotor air ducts on the side facing the cooling assembly. The cooling air ducts and the rotor air ducts on both sides are respectively connected axially to form two circulating air ducts, so that the high-temperature airflow in the rotor air duct and the cooling airflow in the cooling air duct can achieve continuous convection and circulating heat exchange through the circulating air ducts.

[0031] This invention utilizes a dual-airflow circulating cooling structure to provide air cooling for the rotor assembly, efficiently removing the heat generated during rotor assembly operation and reducing its operating temperature. This structure not only effectively suppresses the risk of permanent magnet demagnetization caused by high temperatures but also ensures the stability of the motor's output torque and the continuous improvement of operating efficiency, avoiding performance degradation caused by temperature rise, thereby improving the operational reliability of the axial flux motor. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of an axial flux motor provided in a specific embodiment of the present invention;

[0034] Figure 2 for Figure 1 A sectional view;

[0035] Figure 3 for Figure 1 Assembly diagram of the rotor assembly, cooling assembly, inner support ring, outer support ring, and rotor support;

[0036] Figure 4 for Figure 1 Assembly diagram of the intermediate cooling assembly, inner support ring, outer support ring, and rotor bracket;

[0037] Figure 5 for Figure 4 A partial sectional view;

[0038] Figure 6 for Figure 1 Assembly diagram of the intermediate cooling assembly and stator assembly;

[0039] Figure 7 for Figure 1Assembly diagram of the rotor disk and rotor magnetic poles of the intermediate rotor assembly;

[0040] Figure 8 for Figure 1 Assembly diagram of the central cooling assembly, inner support ring, and outer support ring;

[0041] Figure 9 for Figure 8 Layout diagram of the intermediate cooling assembly between the inner and outer support rings;

[0042] Figure 10 for Figure 1 A schematic diagram of the middle stator module;

[0043] Figure 11 for Figure 10 Schematic diagram of liquid cooling bushing;

[0044] Figure 12 for Figure 1 A schematic diagram of the intermediate cooling module;

[0045] Figure 13 for Figure 12 Exploded view;

[0046] Figure 14 for Figure 12 Schematic diagram of Chinese and foreign fixed blocks;

[0047] Figure 15 for Figure 14 A sectional view;

[0048] Figure 16 for Figure 12 Assembly diagram of the inner cooling core;

[0049] Figure 17 for Figure 12 Cross-sectional view of the liquid cooling block;

[0050] Figure 18 for Figure 1 Assembly diagram of the rotor assembly and rotor support;

[0051] Figure 19 for Figure 18 Schematic diagram of the rotor support.

[0052] The attached figures are labeled as follows:

[0053] Rotor assembly 1, cooling assembly 2, inner support ring 3, outer support ring 4, rotor bracket 5, stator assembly 6, shaft 7, end cover 8, and bearing assembly 9;

[0054] Rotor disc 11, rotor air duct 12 and rotor magnetic pole 13;

[0055] Cooling air duct 21, cooling module 22 and liquid cooling pipe 23;

[0056] Internal cooling core 221 and external fixing block 222;

[0057] Inclined plate 2221, pressure plate 2222, first protrusion 2223 and second protrusion 2224;

[0058] Receiving tank 2221-1;

[0059] 2222-1 strip;

[0060] Liquid cooling block 2211, heat-conducting rod 2212 and support plate 2213;

[0061] Liquid collecting chamber 2211-1, partition plate 2211-2, liquid inlet chamber 2211-3, liquid outlet chamber 2211-4, inner cover plate 2211-5, outer cover plate 2211-6, liquid inlet pipe 2211-7, liquid outlet pipe 2211-8, and gap 2211-9;

[0062] Radial through hole 31 and inner flange ring 32;

[0063] Outer flange ring 41 and axial through hole 42;

[0064] Inner ring 51, outer ring 52 and connecting ring 53;

[0065] Annular protrusion 521, axial air duct 522, and fixed flange 523;

[0066] Inner annular groove 511;

[0067] First ring 531, second ring 532 and weight reduction hole 533;

[0068] Stator module 61;

[0069] Slot 611, stator core 612, stator winding 613, and liquid cooling bushing 614;

[0070] 6121 protruding ridge;

[0071] Bearing 91, inner bushing 92, outer bushing 93, and cover 94;

[0072] Outer convex ring 931;

[0073] Inner convex ring 921. Detailed Implementation

[0074] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0075] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0076] First, it should be noted that, taking the shaft 7 of the axial flux motor as a reference, the axial direction in this article refers to the direction of the center line of the shaft 7, the radial direction refers to the direction of the radius of the shaft 7, and the circumferential direction refers to the direction tangent to the radius of the shaft 7.

[0077] This invention discloses an axial flux motor, including a rotor assembly 1 and a cooling assembly 2. The cooling assembly 2 is axially disposed between two rotor disks 11 of the rotor assembly 1 to directly cool the rotor assembly 1.

[0078] The cooling assembly 2 has a radially penetrating cooling air duct 21 inside. Each of the two rotor disks 11 has a radially penetrating rotor air duct 12 on the side facing the cooling assembly 2. The cooling air duct 21 and the rotor air ducts 12 on both sides are axially connected to each other, forming two circulating air ducts. This allows the high-temperature airflow in the rotor air duct 12 and the cooling airflow in the cooling air duct 21 to achieve continuous convection and circulating heat exchange through the circulating air ducts. Considering that the rotor air ducts 12 of the two rotor disks 11 share a single cooling air duct 21, the airflow directions of the two circulating air ducts are completely opposite.

[0079] This invention utilizes a dual-airflow circulating cooling structure to provide air cooling for the rotor assembly 1, efficiently removing the heat generated during operation and reducing its operating temperature. This structure not only effectively suppresses the risk of permanent magnet demagnetization due to high temperatures but also ensures the stability of the motor's output torque and the continuous improvement of its operating efficiency, avoiding performance degradation caused by temperature rise and thus improving the reliability of the axial flux motor.

[0080] In a preferred embodiment, the rotor assembly 1 includes two rotor disks 11 distributed along the axial direction. A plurality of rotor magnetic poles 13 are fixed on opposite sides of the two rotor disks 11. With the center line of the rotor disk 11 as a reference, all rotor magnetic poles 13 are evenly distributed on the rotor disk 11 in the circumferential direction, and a rotor air duct 12 is formed between two adjacent rotor magnetic poles 13.

[0081] In a preferred embodiment, the axial flux motor further includes an inner support ring 3, an outer support ring 4, and a rotor support 5. The cooling assembly 2 is fixed between the inner support ring 3 and the outer support ring 4. The inner sidewall of the outer support ring 4 has a protruding outer flange ring 41 that is fixedly connected to the cooling assembly 2. Specifically, the inner sidewall of the outer support ring 4 has two protruding outer flange rings 41, and the cooling module 22 is located between the two outer flange rings 41, with both ends of the cooling module 22 fixedly connected to the two outer flange rings 41 respectively. The outer flange ring 41 has an axial through hole 42 that guides the high-temperature airflow in the rotor air duct 12 to flow axially into the cooling air duct 21 of the cooling assembly 2. The sidewall of the inner support ring 3 has a radial through hole 31 that ensures that the cooling airflow in the cooling air duct 21 can be discharged radially through the inner support ring 3. Specifically, the inner support ring 3 has several radial through holes 31 on its side wall. All radial through holes 31 are evenly distributed along the circumference of the inner support ring 3 to ensure that the cooling airflow is evenly distributed in the circumferential direction, effectively preventing heat accumulation in the rotor assembly 1 due to insufficient local heat dissipation.

[0082] The rotor support 5 is coaxially mounted within the inner support ring 3, and its two ends are fixedly connected to the two rotor disks 11, providing stable structural support for the two rotor disks 11. The outer surface of the rotor support 5 has an annular protrusion 521, and two independent axial air ducts 522 are formed on both sides of the annular protrusion 521, with opposite airflow directions. Each set of axial air ducts 522 serves as a directional delivery channel for cooling airflow, accurately guiding the cooling airflow from the cooling air duct 21 axially to the corresponding rotor air duct 12, providing efficient directional cooling for the rotor disks 11.

[0083] One end of each rotor air duct 12 is connected to the cooling air duct 21 through an axial through-hole 42, and the other end is connected to the cooling air duct 21 through one of the axial air ducts 522 and a radial through-hole 31, forming a circulating air duct. During the operation of the rotor assembly 1, the heat generated is caused by the heating of the surrounding air to form a high-temperature airflow. Driven by the centrifugal force of the rotor assembly 1, the high-temperature airflow flows radially outward along the rotor air duct 12 and enters the cooling air duct 21 axially through the axial through-hole 42. In the cooling air duct 21, the high-temperature airflow and the cooling airflow undergo forced convection heat exchange. The cooled airflow is discharged from the inner support ring 3 through the radial through-hole 31 and flows back into the rotor air duct 12 under the guidance of the axial air duct 522, forming a continuous circulating cooling loop to achieve efficient directional heat dissipation of the rotor assembly 1.

[0084] In a preferred embodiment, the axial flux motor further includes a stator assembly 6, which is fixed between the inner support ring 3 and the outer support ring 4. The stator assembly 6 includes several sets of stator modules 61, and the cooling assembly 2 includes several sets of cooling modules 22. All stator modules 61 and all cooling modules 22 are evenly distributed along the axial direction. Crucially, all stator modules 61 and all cooling modules 22 are arranged alternately in the circumferential direction. The pressure strips 2222-1 of the cooling modules 22 and the slots 611 of the stator modules 61 engage circumferentially, forming an interlocking structure between adjacent stator modules 61 and cooling modules 22, thus improving the overall structural rigidity of the axial flux motor. Simultaneously, the stator modules 61 and the cooling assembly 2 achieve efficient heat exchange through close contact, allowing the cooling assembly 2 to simultaneously dissipate heat from both the stator assembly 6 and the rotor assembly 1. This integrated design enables the cooling assembly 2 to perform both cooling and fixing functions, effectively suppressing local temperature rise during motor operation and improving the operational reliability of the axial flux motor.

[0085] Each stator module 61 includes a stator core 612, several sets of stator windings 613 wound on the stator core 612, and a liquid-cooled bushing 614 sleeved on the stator core 612. The liquid-cooled bushing 614 is located between two adjacent sets of stator windings 613. The liquid-cooled bushing 614 exchanges heat with the stator core 612 and the stator windings 613 respectively through coolant, so that each stator module 61 can achieve efficient heat dissipation by liquid cooling, effectively reduce the working temperature of the stator core 612 and the stator windings 613, improve the heat dissipation capacity of the stator assembly 6, extend the life of the insulation material, and improve the overall working reliability of the axial flux motor.

[0086] In a preferred embodiment, all cooling modules 22 of the cooling assembly 2 are evenly distributed circumferentially. Each cooling module 22 includes an inner cooling core 221 and an outer fixing block 222 fixed between two adjacent sets of stator modules 61. That is, the cooling module 22 adopts an integrated design, which has the dual functions of efficient cooling and reliable fixation. A cooling air channel 21 is formed inside the outer fixing block 222, and the inner cooling core 221 is fixed inside the cooling air channel 21.

[0087] The inner cooling core 221 includes a liquid cooling block 2211, several heat-conducting rods 2212, and two support plates 2213 respectively fixed to the heat-conducting rods 2212. The two support plates 2213 are in contact with the side walls of the cooling air duct 21. The liquid cooling block 2211 is provided with a liquid collecting chamber 2211-1 for containing coolant. All the heat-conducting rods 2212 pass through the liquid collecting chamber 2211-1 and extend into the cooling air duct 21. The hot air in the cooling air duct 21 exchanges heat with the coolant through the heat-conducting rods 2212.

[0088] During the operation of the cooling module 22, the hot air flowing through the cooling air duct 21 first comes into contact with the heat-conducting rod 2212 to complete air-cooled heat exchange, and the cooled air after heat exchange is discharged along the cooling air duct 21. Subsequently, the heat-conducting rod 2212 rapidly transfers the captured heat to the liquid cooling block 2211, and liquid cooling is achieved by relying on the coolant. This means that the cooling module 22 in this invention adopts a composite heat dissipation method that combines air cooling and liquid cooling. Compared with the traditional single air cooling method that relies solely on air convection, it increases the heat exchange path in structure, overcomes the problem of limited heat dissipation efficiency caused by the low specific heat capacity of air in traditional air cooling, and effectively improves heat dissipation efficiency.

[0089] In a preferred embodiment, the outer fixing block 222 is fixed between the inner support ring 3 and the outer support ring 4 to reliably fix each cooling module 22. An annular cavity is formed between the outer side of the inner support ring 3 and the inner sidewall of the outer support ring 4, and the outer fixing blocks 222 of each cooling module 22 are evenly arranged circumferentially within the annular cavity. The axial cross-section of the outer fixing block 222 is an isosceles trapezoid. Specifically, in the radial direction from the inner support ring 3 to the outer support ring 4, the axial width of the outer fixing block 222 gradually increases, maximizing the size of the cooling module 22 within a limited space. This not only effectively fills the space between adjacent stator modules 61 but also increases the heat dissipation area of ​​the cooling module 22, which is beneficial for improving fixing reliability and heat dissipation efficiency.

[0090] In a preferred embodiment, the outer fixing block 222 has a first protrusion 2223 at one end facing the inner support ring 3. The first protrusion 2223 extends radially along the inner support ring 3. The first protrusion 2223 and the radial through hole 31 of the inner support ring 3 are radially concave and convex, which can both define the position of each cooling module 22 in the circumferential direction and increase the contact area between the outer fixing block 222 and the inner support ring 3, thereby improving the connection reliability between the outer fixing block 222 and the inner support ring 3. Further, the two ends of the first protrusion 2223 are respectively provided with a first connecting groove extending axially along the inner support ring 3. The two end faces of the inner support ring 3 are respectively formed with inner flange rings 32, and the inner flange rings 32 are formed with first fixing holes. The first connecting groove and the first fixing hole are fixedly connected by a first fastener to ensure that the outer fixing block 222 of each cooling module 22 is reliably fixed on the inner support ring 3. Both the first connecting groove and the first fixing hole can be threaded holes, and they are correspondingly connected along the axial direction of the inner support ring 3. The first fastener can specifically fasten screws, but is not limited to this.

[0091] As a preferred embodiment, considering that the air inlet of the cooling duct 21 remains open, to increase the reliability of the connection between the outer fixing block 222 and the outer support ring 4, two second protrusions 2224 are formed on the end of the outer fixing block 222 facing the outer support ring 4. The two second protrusions 2224 are respectively located on both sides of the opening of the cooling duct 21 and distributed along the axial direction of the outer support ring 4. Two annular grooves are formed on the inner sidewall of the outer support ring 4, and the two second protrusions 2224 are matched with the two annular grooves one by one, so that the inner support ring 3 and the outer support ring 4 cooperate to radially limit the position of each cooling module 22, avoiding the cooling module 22 from being unstable due to excessive centrifugal stress during the high-speed rotation of the axial flux motor, thereby improving the reliability of the connection between the outer fixing block 222 and the outer support ring 4. Furthermore, each of the two second protrusions 2224 is provided with a second connecting groove extending axially along the outer support ring 4. Outer flange rings 41 are formed on both end faces of the outer support ring 4, and each outer flange ring 41 has a second fixing hole. The second connecting groove and the second fixing hole are fixedly connected by a second fastener, ensuring that the outer fixing blocks 222 of each cooling module 22 are reliably fixed on the outer support ring 4. The second connecting groove is a threaded groove, and the second fixing hole is a threaded hole; the second connecting groove and the second fixing hole are axially connected to each other along the outer support ring 4. The second fastener can also be a fastening screw.

[0092] In a preferred embodiment, the two second protrusions 2224 extend from the bottom of the cooling air duct 21 until they intersect with the first protrusion 2223. By extending the radial length of the second protrusions 2224, the contact area between the cooling air duct 21 and the external air can be increased, thereby improving heat exchange efficiency and simultaneously enhancing the structural strength of the cooling module 22. The first protrusion 2223 is provided with an exhaust vent, which is radially connected to the cooling air duct 21 along the inner support ring 3, ensuring that the cooled air after heat exchange within the cooling air duct 21 is discharged through the exhaust vent.

[0093] In a preferred embodiment, all heat-conducting rods 2212 are parallel to each other and extend along the axial direction of the inner support ring 3, forming a conduction matrix. Based on this structure, both ends of each group of heat-conducting rods 2212 extend into the cooling duct 21, increasing the contact area between the heat-conducting rods 2212 and the coolant, which is beneficial for improving heat exchange efficiency. More importantly, in addition to heat exchange, the parallel structure formed by each heat-conducting rod 2212 between the cooling duct 21 and the liquid collection chamber 2211-1 increases the axial structural rigidity of the cooling module 22.

[0094] In a preferred embodiment, the support plate 2213 is provided with a plurality of support holes, all of which correspond one-to-one with all the heat-conducting rods 2212, ensuring that all the heat-conducting rods 2212 remain axially aligned and preventing the heat-conducting rods 2212 from bending, thereby effectively improving the service life of the cooling module 22. Specifically, each cooling module 22 includes two support plates 2213, which are located at both ends of each heat-conducting rod 2212, and the two support plates 2213 are respectively attached to the opposite side walls of the cooling air duct 21.

[0095] In a preferred embodiment, the outer fixing block 222 has a heat-conducting layer on the side facing the stator module 61. The adjacent cooling module 22 and the stator module 61 exchange heat through the heat-conducting layer, improving the heat conduction capacity between the stator module 61 and the adjacent cooling module 22, thereby improving heat dissipation efficiency. The heat-conducting layer can be thermally conductive silicone, serving both heat conduction and fixing purposes, but is not limited to this.

[0096] The liquid cooling block 2211 of the cooling module 221 is connected to the liquid cooling sleeve 614 of the adjacent stator module 61 through the liquid cooling pipe 23, thus constructing a liquid cooling circulation system between the rotor assembly 1 and the stator assembly 6. This allows the cooling module 2 to simultaneously provide liquid cooling heat dissipation to both the rotor assembly 1 and the stator assembly 6, improving the overall heat dissipation efficiency and thermal balance of the machine. This ensures that the motor can operate continuously and stably under high power conditions, prevents performance degradation caused by local overheating, and improves the working reliability of the axial flux motor.

[0097] In a preferred embodiment, each cooling module 22 is positioned between two adjacent stator modules 61. The outer fixing block 222 includes two angled inclined plates 2221 and two parallel pressure plates 2222. Each of the two inclined plates 2221 has a receiving groove 2221-1 on its side facing the stator module 61, and the receiving groove 2221-1 has a heat-conducting layer. The two pressure plates 2222 are fixedly connected to the two ends of the inclined plates 2221, and pressure strips 2222-1 are formed on the portions of each pressure plate 2222 that extend beyond the inclined plates 2221. The end of the stator core 612 has a circumferentially extending protruding rib 6121, which forms a groove 611 with the end face of the adjacent stator winding 613. The pressure strip 2222-1 cooperates with the groove 611 along the circumference of the outer support ring 4 to limit accidental axial misalignment of each stator module 61, reduce the failure rate, and thus improve the reliability of the axial flux motor.

[0098] In a preferred embodiment, the axial width of the liquid collecting cavity 2211-1 gradually increases in the radial direction from the inner support ring 3 to the outer support ring 4. A partition plate 2211-2 is fixedly installed inside the liquid collecting cavity 2211-1, dividing it into an inlet cavity 2211-3 and an outlet cavity 2211-4. The liquid cooling block 2211 includes an inner cover plate 2211-5 and an outer cover plate 2211-6. The inner cover plate 2211-5 is located at the air outlet of the cooling air duct 21, and the outer cover plate 2211-6 is located at the air inlet of the cooling air duct 21. The outer cover plate 2211-6 has an inlet pipe 2211-7 and an outlet pipe 2211-8. The inlet pipe 2211-7 is connected to the inlet cavity 2211-3, and the outlet pipe 2211-8 is connected to the outlet cavity 2211-4. The partition plate 2211-2 is perpendicularly connected to the outer cover plate 2211-6. A gap 2211-9 is formed between the partition plate 2211-2 and the inner cover plate 2211-5, which connects the inlet chamber 2211-3 and the outlet chamber 2211-4. By setting the partition plate 2211-2 in the liquid collecting chamber 2211-1, the flow path between the inlet pipe 2211-7 and the outlet pipe 2211-8 is extended, ensuring that the coolant flows fully in the liquid collecting chamber 2211-1 and improving the heat exchange efficiency.

[0099] The rotor support 5 is connected between two rotor disks 11, both of which are annular in shape, and their outer and inner diameters are respectively equal. The rotor support 5 includes an inner ring 51 and an outer ring 52 coaxially disposed on the outer periphery of the inner ring 51. Both the inner ring 51 and the outer ring 52 are made of rolled steel plates. The inner ring 51 is thermally fitted to the rotating shaft 7, and the two ends of the outer ring 52 are respectively formed with annular surfaces for mounting the two rotor disks 11.

[0100] The two end faces of the outer ring 52 are directly connected to the edges of the central holes of the two rotor disks 11. Specifically, the two rotor disks 11 have central holes, the edges of which are fixedly connected to the two end faces of the outer ring 52. By enlarging the inner diameter of the central holes of the rotor disks 11 through the outer ring 52, the ratio of the outer diameter to the inner diameter of the two rotor disks 11 is effectively reduced, enhancing the structural rigidity of the two rotor disks 11, suppressing the central deflection caused by centrifugal force under high-speed rotation, ensuring the flatness of the rotor working surface, and thus ensuring the uniformity of the air gap of the axial flux motor. By stabilizing the magnetic field, losses are effectively reduced, thereby increasing the power density of the axial flux motor and enabling it to meet the needs of high-power applications. On this basis, the increased inner diameter also directly reduces the mass of the rotor disks 11, effectively reducing the centrifugal stress generated during high-speed rotation, thereby reducing the risk of fatigue cracks in the central holes of the two rotor disks 11. This allows the two rotor disks 11 to withstand higher speeds and power, thus enabling the axial flux motor to adapt to high-power applications, expanding its adaptability and improving its overall suitability.

[0101] As a preferred embodiment, the outer ring 52 is axially connected to the central holes of the two rotor disks 11, and the three have equal inner diameters, forming a smooth and equal-diameter continuous through shaft cavity. This not only optimizes the aerodynamic performance of the two rotor disks 11 and reduces the internal air friction loss of the two rotor disks 11, but also ensures the symmetry of the centroid distribution of the rotor assembly 1, effectively reduces the risk of dynamic imbalance under high-speed rotation, and enhances the structural rigidity of the rotor assembly 1, laying the foundation for high-power application scenarios.

[0102] The outer ring 52 has fixed flanges 523 protruding from both ends of its outer side. The end faces of the two fixed flanges 523 are respectively attached to the edges of the central holes of the two rotor disks 11, thereby increasing the contact area between the outer ring 52 and the central holes of the two rotor disks 11, improving the connection rigidity between the outer ring 52 and the two rotor disks 11, and thus improving the connection reliability between the rotor support 5 and the two rotor disks.

[0103] The center holes of the two rotor disks 11 have positioning grooves formed along their edges, which axially engage with the end face of the fixed flange 523. This effectively constrains the relative position between the two rotor disks 11, improves the axial positioning accuracy between the outer ring 52 and the two rotor disks 11, thereby improving the coaxiality between the two rotor disks 11. This provides conditions for maintaining the uniformity of the air gap in the yokeless axial flux motor, and lays the foundation for high-power applications.

[0104] An annular groove is formed between the two fixed flanges 523; an annular protrusion 521 is formed on the outer side of the outer ring 52. The annular protrusion 521 is used to divide the annular groove into two independent axial air channels 522, avoiding mixing of cooling airflow in the two axial air channels 522, thereby preventing a decrease in cooling efficiency due to airflow mixing, ensuring efficient cooling of the two rotor disks 11, and thus improving the operational reliability of the yokeless axial flux motor. Preferably, the two rotor disks 11 have equal thickness, and the annular protrusion 521 is located at the center of the outer side of the outer ring 52, ensuring that the two rotor disks 11 are symmetrically arranged on both sides of the annular protrusion 521, effectively balancing the rotational inertia of the two rotor disks 11.

[0105] The rotor support 5 also includes a connecting ring 53 fixed between the inner ring 51 and the outer ring 52. The length of the inner ring 51 is less than the length of the outer ring 52. The connecting ring 53 includes a first ring body 531 and a second ring body 532 fixed to both ends of the inner ring 51, respectively. By increasing the span of the connecting ring 53, the support width of the connecting ring 53 between the inner ring 51 and the outer ring 52 is increased, effectively transmitting and dispersing the load between the inner ring 51 and the outer ring 52, improving the connection stiffness between the inner ring 51 and the outer ring 52, reducing the risk of deformation of the rotor support 5 due to centrifugal force under high-speed rotation, and thus improving the structural stability of the rotor support 5.

[0106] Both the first ring 531 and the second ring 532 are provided with weight-reducing holes 533. This effectively reduces the weight of the rotor support 5 by reducing material usage, preventing excessive centrifugal stress caused by its own weight during high-speed rotation. This effectively improves the structural reliability of the rotor support 5, making it suitable for high-power applications. The weight-reducing holes 533 in both the first ring 531 and the second ring 532 are axially aligned and interconnected, which helps improve the processing efficiency of the rotor support 5. Furthermore, the inner wall of the inner ring 51 is provided with an inner annular groove 511 to further reduce the weight of the rotor support 5, thereby reducing the centrifugal stress generated during high-speed rotation and further improving the structural reliability of the rotor support 5.

[0107] Along the axial direction, both the annular protrusion 521 of the outer ring 52 and the inner annular groove 511 of the inner ring 51 are located between the first ring body 531 and the second ring body 532. That is, the annular protrusion 521 and the inner annular groove 511 are both offset from the two ring bodies along the axial direction, forming a stress isolation zone. This avoids the spatial superposition of stresses from different sources, reduces the risk of fatigue damage caused by alternating stress during high-speed rotation of the rotor support 5, and effectively improves the service life of the rotor support 5.

[0108] In a preferred embodiment, the axial flux motor further includes a rotating shaft 7 and two end caps 8 respectively fitted onto both ends of the rotating shaft 7. The two end caps 8 are fixed to both ends of the outer support ring 4, forming a closed mounting frame that effectively protects the internal rotor assembly 1 and cooling assembly 2 from external environmental interference, improving the overall reliability of the machine. A bearing assembly 9 is provided between the rotating shaft 7 and the end caps 8. The bearing assembly 9 includes a bearing 91 and an inner bushing 92 and an outer bushing 93 respectively located at both ends of the bearing 91. Both are fitted onto the rotating shaft 7. A stop cover 94 is provided between the outer bushing 93 and the rotating shaft 7, forming a multi-stage axial positioning structure. This achieves precise positioning of the bearing 91, effectively suppressing axial movement of the rotor at high speeds, improving positioning accuracy, and reducing wear on the bearing 91, providing an important guarantee for the stable output of the motor's high dynamic performance.

[0109] The inner ring of bearing 91 abuts against the shoulders of cover 94 and shaft 7 along the axial direction at both ends, and the outer ring of bearing 91 abuts against the outer convex ring 931 of outer bushing 93 and the inner convex ring 921 of inner bushing 92 along the axial direction at both ends, thereby achieving axial positioning of the inner and outer rings of bearing 91, effectively suppressing axial movement under high-speed conditions, improving the positioning accuracy of rotor assembly 1, reducing the risk of early failure of bearing 91 due to fretting wear, and thus improving the working reliability of axial flux motor.

[0110] It should be noted that in this specification, relational terms such as first and second are used only to distinguish one entity from several other entities, and do not necessarily require or imply any such actual relationship or order between these entities.

[0111] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. An axial flux electric machine, characterized by, The application relates to a rotor assembly (1) and a cooling assembly (2); the cooling assembly (2) is arranged between two rotor discs (11) of the rotor assembly (1) in the axial direction; The cooling assembly (2) is internally provided with a cooling air channel (21) penetrating in the radial direction; the two rotor discs (11) are both formed with rotor air channels (12) penetrating in the radial direction on the side facing the cooling assembly (2); the cooling air channel (21) and the rotor air channels (12) arranged on the two sides are respectively connected in the axial direction, forming two circulating air channels; The high-temperature airflow in the rotor air channel (12) and the cooling airflow in the cooling air channel (21) are circulated and heat-exchanged through the circulating air channels.

2. An axial flux machine according to claim 1, characterised in that, The application further comprises an inner support ring (3), an outer support ring (4) and a rotor support (5); the cooling assembly (2) is fixed between the inner support ring (3) and the outer support ring (4); the inner side wall of the outer support ring (4) is provided with an outer flange ring (41) fixed with the cooling assembly (2); the outer flange ring (41) is provided with an axial through hole (42) penetrating in the axial direction; the side wall of the inner support ring (3) is provided with a radial through hole (31) penetrating in the radial direction; The rotor support (5) is coaxially arranged in the inner support ring (3); the two ends of the rotor support (5) are respectively fixed with the two rotor discs (11); the outer side of the rotor support (5) is provided with an annular protrusion (521); the two sides of the annular protrusion (521) are formed with two independent axial air channels (522); One end of each group of rotor air channels (12) is connected with the cooling air channel (21) through the axial through hole (42); the other end is connected with the cooling air channel (21) through one of the axial air channels (522) and the radial through hole (31), forming the circulating air channels.

3. The axial flux machine of claim 1, wherein, The application further comprises a stator assembly (6); the stator assembly (6) comprises a plurality of groups of stator modules (61); all the stator modules (61) and all the cooling modules (22) of the cooling assembly (2) are alternately arranged in the circumferential direction; the pressing strip (2222-1) of the cooling module (22) and the clamping groove (611) of the stator module (61) are matched in the circumferential direction; Each group of stator modules (61) comprises a stator core (612), a plurality of groups of stator windings (613) wound on the stator core (612) and a liquid cooling sleeve (614) sleeved on the stator core (612); the liquid cooling sleeve (614) is arranged between two adjacent groups of stator windings (613); the liquid cooling sleeve (614) exchanges heat with the stator core (612) and the stator windings (613) through cooling liquid.

4. The axial flux machine of claim 3, wherein, The cooling assembly (2) comprises a plurality of groups of cooling modules (22); each group of cooling modules (22) comprises an inner cooling core (221) and an outer fixed block (222) fixed between two adjacent groups of stator modules (61); the inner part of the outer fixed block (222) is formed with the cooling air channel (21); the inner cooling core (221) is fixed in the cooling air channel (21); The inner cooling core (221) comprises a liquid cooling block (2211), a plurality of heat-conducting rods (2212) and two support plates (2213) respectively fixed at two ends of the heat-conducting rods (2212); the liquid cooling block (2211) is provided with a liquid collecting cavity (2211-1), all the heat-conducting rods (2212) pass through the liquid collecting cavity (2211-1) and extend into the cooling air duct (21), and hot air in the cooling air duct (21) exchanges heat with cooling liquid in the liquid cooling block (2211) through the heat-conducting rods (2212); the two support plates (2213) are respectively attached to two side walls of the cooling air duct (21).

5. An axial flux machine according to claim 4, wherein, The outer fixing block (222) is provided with a heat-conducting layer on a side facing the stator module (61), and adjacent cooling modules (22) and the stator module (61) exchange heat through the heat-conducting layer; The liquid cooling block (2211) of the cooling module (22) is connected with a liquid cooling pipe (23) of the liquid cooling sleeve (614) of the adjacent stator module (61).

6. The axial flux machine of claim 5, wherein, The outer fixing block (222) comprises two inclined plates (2221) arranged at an angle and two parallel pressing plates (2222); the two inclined plates (2221) are respectively provided with accommodating grooves (2221-1) on a side facing the stator module (61), and the heat-conducting layer is arranged in the accommodating grooves (2221-1); The two pressing plates (2222) are respectively fixed at two ends of the inclined plates (2221), and the portions of the two ends of each pressing plate (2222) exceeding the inclined plates (2221) are formed with a pressing strip (2222-1) extending in the circumferential direction; the end portion of the stator core (612) is provided with a convex rib (6121) extending in the circumferential direction, and a clamping groove (611) is formed between the convex rib (6121) and the end face of the adjacent stator winding (613), and the pressing strip (2222-1) and the clamping groove (611) are in circumferential concave-convex matching.

7. The axial flux machine of claim 4, wherein, A partition plate (2211-2) is fixed in the liquid collecting cavity (2211-1), and the partition plate (2211-2) is used for dividing the liquid collecting cavity (2211-1) into a liquid inlet cavity (2211-3) and a liquid outlet cavity (2211-4); The liquid cooling block (2211) comprises an inner cover plate (2211-5) and an outer cover plate (2211-6), the inner cover plate (2211-5) is arranged at an air outlet of the cooling air duct (21), and the outer cover plate (2211-6) is arranged at an air inlet of the cooling air duct (21); the outer cover plate (2211-6) is provided with a liquid inlet pipe (2211-7) and a liquid outlet pipe (2211-8), the liquid inlet pipe (2211-7) is connected with the liquid inlet cavity (2211-3), and the liquid outlet pipe (2211-8) is connected with the liquid outlet cavity (2211-4); The partition plate (2211-2) is connected perpendicularly with the outer cover plate (2211-6), and a gap (2211-9) is formed between the partition plate (2211-2) and the inner cover plate (2211-5), which communicates the liquid inlet cavity (2211-3) and the liquid outlet cavity (2211-4).

8. The axial flux machine of claim 2, wherein, The rotor support (5) comprises an inner ring (51) and an outer ring (52) coaxially arranged outside the inner ring (51); the end of the outer ring (52) is protruded to form two fixed flanges (523), and the two fixed flanges (523) are respectively fixedly connected with two rotor discs (11); An annular recess is formed between the two fixed flanges (523), and the annular protrusion (521) is protruded in the annular recess, which divides the annular recess into two axial air ducts (522); The end surface of the fixed flange (523) is attached to the hole along of the central hole of the connected rotor disc (11), and the inner diameter of the outer ring (52) is equal to the inner diameter of the central hole of the two rotor discs (11).

9. An axial flux machine according to claim 8, characterised in that, The rotor support (5) further comprises a connecting ring (53) fixedly connected between the inner ring (51) and the outer ring (52); the length of the inner ring (51) is less than the length of the outer ring (52), and the inner side wall of the inner ring (51) is provided with an inner side ring groove (511); The connecting ring (53) comprises a first ring body (531) and a second ring body (532) respectively fixedly connected with both ends of the inner ring (51), and both the first ring body (531) and the second ring body (532) are provided with weight-reducing holes (533).

10. The axial flux machine of claim 2, wherein, It also comprises a rotating shaft (7) and two end covers (8) respectively sleeved on both ends of the rotating shaft (7), and the two end covers (8) are respectively fixedly arranged at both ends of the outer support ring (4); A bearing assembly (9) is arranged between the rotating shaft (7) and the end cover (8), and the bearing assembly (9) comprises a bearing (91), an inner shaft sleeve (92) and an outer shaft sleeve (93) respectively arranged at both ends of the bearing (91), both of which are sleeved on the rotating shaft (7); a cover (94) is arranged between the outer shaft sleeve (93) and the rotating shaft (7); The inner ring of the bearing (91) is respectively abutted with the shoulder of the cover (94) and the rotating shaft (7) along the axial direction, and the outer ring of the bearing (91) is respectively abutted with the outer protruding ring (931) of the outer shaft sleeve (93) and the inner protruding ring (921) of the inner shaft sleeve (92) along the axial direction.

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