Axial flux motor cooling structure
By introducing heat dissipation channels and heat pipes into the rotor and stator structures of the axial flux motor, the problem of difficult internal heat dissipation of the motor is solved, achieving efficient internal cooling and improving the stability and lifespan of the motor.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- TIANRUI MAGLEV INTELLIGENT MANUFACTURING (SHANDONG) CO LTD
- Filing Date
- 2026-04-16
- Publication Date
- 2026-05-15
AI Technical Summary
Axial flux motors have difficulty dissipating heat internally, leading to increased temperatures in the magnets and shaft, which affects the motor's stability and safety.
Heat dissipation channels and heat dissipation pipes are introduced into the rotor and stator structures to dissipate heat internally through cooling medium channels, including rotor axial cooling channels and heat dissipation pipes on the stator tooth surfaces, combined with sealing structures and heat insulation groove designs.
It effectively reduces the internal temperature of the motor, improves the stability and service life of the motor, reduces costs, and increases the critical speed.
Smart Images
Figure CN122052369A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the field of axial flux motor technology, in particular to an axial flux motor cooling structure. BACKGROUND
[0002] As a very potential motor topology structure, the electromagnetic connection of the stator of the axial flux motor is parallel to the disc-shaped rotor containing permanent magnets. The axial flux motor has compact structure and high power density, and has very broad application prospect, but the heat dissipation problem caused by the compact structure is also a difficult problem to be solved at present. The commonly used method to reduce temperature rise is to use water cooling or oil cooling, which is mostly used for cooling the motor shell, and rarely for cooling the motor interior. For the heat generated by the eddy current loss of the magnetic steel, the heat needs to be transferred to the stator and the shell to be taken away, which is easy to cause the accumulation of heat in the motor, resulting in high temperature rise of the magnetic steel and the shaft in the motor, affecting the stability of the axial flux motor, and even burning the motor. SUMMARY
[0003] The present application aims to solve the technical problem of difficult heat dissipation in the double-stator single-rotor axial flux motor in the prior art, and provides an axial flux motor cooling structure.
[0004] To solve the above technical problems, the technical scheme adopted by the present application is as follows: an axial flux motor cooling structure, the axial flux motor comprising a shell, a rotor assembly and a stator assembly, the shell forming a containing cavity inside, the stator assembly and the rotor assembly being arranged in the containing cavity along the axial direction of the axial flux motor. The rotor assembly comprises a rotor shaft, two magnetic steel supports coaxially sleeved to the rotor shaft and tightly attached to each other, an axial cooling flow channel being provided on the rotor shaft, a rotor heat dissipation device being provided in the interior of the two magnetic steel supports, the rotor heat dissipation device comprising a heat dissipation medium channel, a heat dissipation medium channel sealing structure and a cooling channel connecting the heat dissipation medium channel and the axial cooling flow channel on the rotor shaft.
[0005] The stator assembly comprises an annular winding group and a plurality of stator teeth inserted into the annular winding group, a stator heat dissipation device being provided on each stator tooth, the stator heat dissipation device comprising a heat dissipation pipe attached to the surface of the stator tooth.
[0006] Further, the magnetic steel support comprises a front magnetic steel support and a rear magnetic steel support, both of which are composed of a main body structure and a plurality of rotor teeth arranged equidistantly along the circumferential direction, and are integrally formed; a magnetic steel baffle is fixedly arranged on the outer side of the magnetic steel support at the rotor tooth; the two magnetic steel supports are attached to each other and fixed by bolts.
[0007] Further, the heat dissipation medium channel comprises a plurality of branch channels and a collecting channel, wherein the branch channels are arranged in the rotor teeth one by one, and the inlets and outlets of the branch channels are connected with the collecting channel; the collecting channel is arranged in the main structure of the magnetic steel support in a ring shape, comprises two coaxial inlet and outlet pipes, and is connected with the axial cooling flow channel of the rotor shaft through two cooling channels; the axial cooling flow channel of the rotor shaft comprises a cooling injection pipe and a cooling outlet pipe.
[0008] Further, the two pipes in the collecting channel are arranged at intervals, and a heat insulation groove is arranged between the two pipes, and a heat insulation component is arranged in the heat insulation groove.
[0009] Further, the heat dissipation medium channel sealing structure is arranged on the contact surface of the two magnetic steel supports, and comprises a boss, a recess and a sealing medium, wherein the boss is arranged on one of the magnetic steel supports, the recess is arranged on the other magnetic steel support opposite to the boss, and the boss can be accommodated in the recess; the recess has a size larger than that of the boss, and the gap between the boss and the recess is filled with the sealing medium.
[0010] Further, the sealing medium is a fluorine rubber sealing strip, and the filling height of the sealing medium is higher than the minimum distance between the boss and the recess, so that the sealing medium fills the entire gap when the boss is pressed and extruded.
[0011] Further, the heat dissipation medium channel sealing structure is arranged on both sides of each branch channel.
[0012] Further, the heat dissipation pipe on the stator tooth is fixed to the surface of the stator tooth through an adhesive with magnetic powder, and the two ends of the heat dissipation pipe near the lower end of the stator tooth are respectively provided with an inlet and an outlet.
[0013] Further, the heat dissipation pipe is arranged in a back shape or a checkered pattern on one side or both sides of the stator tooth.
[0014] Compared with the prior art, the present application has the following advantages: the present application improves the heat dissipation structure from the rotor and the stator structure without damaging the electromagnetic topology structure of the permanent magnet synchronous motor.
[0015] Firstly, in terms of the rotor, the front and rear support mode is adopted, and the heat dissipation flow channel and the corresponding sealing structure are arranged in the magnetic steel support, which is beneficial to the heat dissipation of the axial flux motor; the heat dissipation flow channel is simple to process and assemble, and reduces the cost; the processing of the heat dissipation flow channel also reduces the weight of the magnetic steel support as a whole, so that the overall mass of the rotor is reduced, which is beneficial to improve the critical speed.
[0016] Secondly, in terms of the stator, the heat dissipation pipe is arranged on the outer surface of the stator tooth, which quickly conducts the heat of the coil and the stator tooth part, and accelerates the heat dissipation. BRIEF DESCRIPTION OF DRAWINGS
[0017] Figure 1 This is a schematic diagram of the magnet support structure in the rotor assembly of the present invention; Figure 2 for Figure 1 Cross-sectional view of the central structure along the radial center plane; Figure 3 for Figure 1 A cross-sectional view of a single rotor tooth; Figure 4 for Figure 3 Enlarged view of the structure of section A in the middle; Figure 5 This is a schematic diagram of the stator assembly structure in this invention; Figure 6 This is a schematic diagram of the stator tooth structure in the stator assembly of the present invention; In the diagram: 1. Rotor assembly, 2. Front magnet bracket, 3. Rear magnet bracket, 4. Magnet baffle, 5. Branch circuit, 6. Combination circuit, 7. Cooling channel, 8. Threaded hole, 9. Boss, 10. Recess, 11. Sealing medium, 12. Gap, 13. Stator teeth, 14. Heat sink. Detailed Implementation
[0018] It should be noted that in the description of this invention, terms such as "front", "rear", "coaxial", "inner", "outer", "ring", "one side", "the other side" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only used to facilitate the description of the structural relationship of each component in this invention and do not specifically mean that any component in this invention must have a specific orientation, or be constructed and operated in a specific orientation. They should not be construed as limitations on this invention.
[0019] Furthermore, in the description of this invention, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0020] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings: A cooling structure for an axial flux motor is provided, which is mainly for internal heat dissipation of the axial flux motor. The axial flux motor includes a housing, a rotor assembly 1 and a stator assembly. An accommodating cavity is formed inside the housing. The stator assembly and the rotor assembly 1 are arranged in the accommodating cavity along the axial direction of the axial flux motor and are relatively parallel. The heat generated by the eddy current loss of the magnets during operation is dissipated through the cooling structure.
[0021] CombinationFigures 1 to 4 As shown, the rotor assembly 1 includes a rotor shaft and two magnet supports coaxially mounted and tightly fitted to the rotor shaft. The rotor shaft has axial cooling channels, divided into a cooling injection pipe and a cooling outlet pipe. The two magnet supports include a front magnet support 2 and a rear magnet support 3, both of which include a central main structure and multiple rotor teeth arranged at equal intervals along the circumference of the main structure. They are integrally formed, and multiple circumferentially arranged threaded holes 8 are provided at the main structure positions of the two magnet supports, through which bolts are inserted to achieve tight fitting and fixation of the two magnet supports. Magnet baffles 4 are fixedly installed on the outer side of the magnet supports at the rotor teeth. Magnets are installed between the magnet baffles 4 between adjacent rotor teeth, together forming the rotor.
[0022] A rotor cooling device is provided between the front magnet support 2 and the rear magnet support 3. The rotor cooling device includes a heat dissipation medium channel, a heat dissipation medium channel sealing structure, and a cooling channel 7 connecting the heat dissipation medium channel to the axial cooling flow channel on the rotor shaft. The heat dissipation medium channel includes multiple branch paths 5 and a confluence path 6. Each branch path 5 is correspondingly located inside the multiple rotor teeth, and each branch path 5 is U-shaped, located on the side of the front magnet support 2 facing the rear magnet support 3. The confluence path 6 is located on the middle main structure of the magnet support, coaxially arranged in a ring with the rotor shaft, and includes two coaxially arranged pipe structures. The inlet and outlet of each branch path 5 are connected to the two pipe structures of the confluence path 6. Furthermore, the two pipe structures in the confluence path 6 are spaced apart, and a heat insulation groove is formed between them. The heat insulation groove is filled with heat insulation components, which may be filled with rubber medium, to prevent heat transfer between the inlet and outlet pipes, thereby improving the cooling effect. The two pipe structures in the above-mentioned confluence path 6 are connected to the axial cooling channel on the rotor shaft through two cooling channels 7, so that the coolant can enter each rotor tooth to remove heat and achieve cooling.
[0023] To prevent coolant leakage within the heat dissipation channels, a heat dissipation channel sealing structure is installed on both sides of each heat dissipation channel, combined with... Figure 3 and Figure 4As shown, the heat dissipation medium channel sealing structure includes a boss 9, a recess 10, and a sealing medium 11. The boss 9 is located on the contact surface of the rear magnet bracket 3 facing the front magnet bracket 2, and the recess 10 is located on the opposite front magnet bracket 2. Each boss 9 can be perfectly accommodated within the corresponding recess 10. The recessed portion of the recess 10 is larger than the protruding portion of the boss 9, leaving a gap 12 between the boss 9 and the recess 10. The sealing medium 11 fills the gap 12. The sealing medium 11 is a fluororubber sealing strip. During assembly, the fluororubber sealing strip is first laid in the recess 10, with its filling height slightly higher than the minimum distance between the boss 9 and the recess 10. After the front magnet bracket 2 and the rear magnet bracket 3 are fixed and compacted with bolts, the fluororubber sealing strip fills the entire gap 12 under the pressure of the boss 9, thus achieving the corresponding sealing effect.
[0024] Combination Figure 5 and Figure 6 As shown, the stator assembly includes an annular winding assembly and several stator teeth 13 inserted into the annular winding assembly. Each stator tooth 13 is equipped with a stator heat dissipation device, which includes a heat dissipation pipe 14 attached to the surface of the stator tooth 13. The two are fixed together by applying an adhesive with magnetic powder to avoid magnetic interference. The heat dissipation pipe 14 is arranged in a U-shape or a tic-tac-toe pattern, and the two ends of the heat dissipation pipe 14 near the lower end of the stator tooth 13 are respectively provided with an inlet and an outlet. The heat dissipation pipe 14 can be arranged on one side or both sides of the stator tooth 13, which can achieve rapid heat conduction and heat dissipation for the stator assembly.
[0025] Combining the heat dissipation devices of the two parts mentioned above, a cooling medium, such as water, is injected under high pressure. The medium flows in one direction and enters the various branch paths 5 of the heat dissipation medium channel through the axial cooling channel and cooling channel 7 on the rotor shaft, thereby achieving rotor cooling, reducing the internal temperature of the axial flux motor, and extending its service life.
[0026] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should also fall within the protection scope of the present invention.
Claims
1. A cooling structure for an axial flux motor, the axial flux motor comprising a housing, a rotor assembly (1), and a stator assembly, wherein a cavity is formed inside the housing, and the stator assembly and the rotor assembly (1) are arranged along the axial direction of the axial flux motor within the cavity, characterized in that: The rotor assembly (1) includes a rotor shaft and two magnet brackets coaxially fitted to and tightly attached to the rotor shaft. The rotor shaft is provided with an axial cooling channel. The two magnet brackets are provided with a rotor heat dissipation device. The rotor heat dissipation device includes a heat dissipation medium channel, a heat dissipation medium channel sealing structure, and a cooling channel (7) connecting the heat dissipation medium channel and the axial cooling channel on the rotor shaft. The stator assembly includes an annular winding assembly and several stator teeth (13) inserted into the annular winding assembly. Each stator tooth (13) is provided with a stator heat dissipation device, which includes a heat dissipation pipe (14) attached to the surface of the stator tooth (13).
2. The axial flux motor cooling structure according to claim 1, characterized in that: The magnet bracket includes a front magnet bracket (2) and a rear magnet bracket (3), both of which are composed of a main structure and multiple rotor teeth arranged at equal intervals along their circumference, and the two are integrally formed; a magnet baffle (4) is fixedly provided on the outside of the magnet bracket at the rotor teeth; the two magnet brackets are attached to each other and fixed by bolts.
3. The axial flux motor cooling structure according to claim 2, characterized in that: The heat dissipation medium channel includes multiple branch paths (5) and a confluence path (6). The branch paths (5) are opened one-to-one inside each rotor tooth, and their inlets and outlets are connected to the confluence path (6). The confluence path (6) is arranged in a ring within the main structure of the magnet support, including two coaxially arranged inlet and outlet pipes, and is connected to the axial cooling channel on the rotor shaft through two cooling channels (7). The axial cooling channel on the rotor shaft includes a cooling injection pipe and a cooling outlet pipe.
4. The axial flux motor cooling structure according to claim 3, characterized in that: The two inlet and outlet pipes in the manifold (6) are spaced apart, and a heat insulation groove is provided between them. A heat insulation component is installed inside the heat insulation groove.
5. The axial flux motor cooling structure according to claim 1, characterized in that: The heat dissipation medium channel sealing structure is provided on the contact surface of the two magnetic steel brackets, including a boss (9), a recess (10) and a sealing medium (11). The boss (9) is provided on one of the magnetic steel brackets, and the recess (10) is provided on the other magnetic steel bracket opposite to it. The boss (9) can be accommodated in the recess (10). The size of the recessed part of the recess (10) is larger than the size of the protruding part of the boss (9), and the gap between the two is filled with the sealing medium (11).
6. The axial flux motor cooling structure according to claim 5, characterized in that: The sealing medium (11) uses a fluororubber sealing strip. The filling height of the sealing medium (11) is higher than the minimum distance between the boss (9) and the concave platform (10). When the boss (9) is compacted and squeezed, the sealing medium (11) fills the entire gap.
7. The axial flux motor cooling structure according to claim 3, characterized in that: Each branch path (5) in the heat dissipation medium channel is provided with a heat dissipation medium channel sealing structure on both sides.
8. The axial flux motor cooling structure according to claim 1, characterized in that: The heat dissipation tube (14) on the stator tooth (13) is fixed to the surface of the stator tooth (13) by an adhesive with magnetic powder. The two ends of the tube near the lower end of the stator tooth (13) are respectively provided with an inlet and an outlet.
9. The axial flux motor cooling structure according to claim 8, characterized in that: The heat dissipation pipe (14) is arranged in a U-shape or a grid shape, and is located on one or both sides of the stator tooth (13).