PCB winding axial flux motor

Abstract

This invention relates to the field of motor technology, specifically to a PCB winding axial flux motor, comprising a rotor, a housing, a stator, and a PCB winding board sleeved on the stator. Two sets of rotors are provided, with a bearing between them. Multiple layers of PCB winding boards are arranged axially around the bearing. A heat dissipation interlayer is provided between adjacent layers of PCB winding boards for heat dissipation. The stator is embedded in the PCB winding board and the heat dissipation interlayer. The surface of the heat dissipation interlayer contacts the surface of the PCB winding board and the side of the stator, transferring and dissipating heat generated by the windings and the stator. This invention has a compact structure, short axial dimension, eliminates the stator yoke, saves materials, reduces core losses, increases torque density, has good thermal conductivity and heat dissipation, and improves the motor's continuous output capability and power density.

Description

Technical Field

[0001] This invention relates to the field of motor technology, and more specifically, to a PCB winding axial flux motor. Background Technology

[0002] Axial flux motors, due to their compact structure and high power density, have broad application prospects in size- and weight-sensitive fields such as electric vehicles, drones, and servo systems. Traditional axial flux motors mostly adopt a wound stator structure, forming the windings by manually or mechanically winding copper wire. This process has problems such as poor production consistency, high batch costs, complex winding ends, and limited heat dissipation performance, which restricts further improvement of motor performance and large-scale application.

[0003] In recent years, printed circuit board (PCB) winding technology has been gradually introduced into the field of motor design. This technology utilizes mature PCB manufacturing processes to etch or deposit windings in the form of copper foil onto an insulating substrate, offering advantages such as design flexibility, high precision, good consistency, and suitability for mass production. Axial flux motors using PCB windings (hereinafter referred to as "PCB-wound axial flux motors") can effectively overcome some of the shortcomings of traditional winding methods, simplify the production process, and reduce manufacturing costs.

[0004] However, existing PCB winding axial flux motor solutions still face some technical bottlenecks: 1. Torque density and efficiency limitations: PCB windings are usually directly attached to non-magnetic substrates (such as FR4), lacking a highly efficient magnetic circuit structure, which leads to limited air gap magnetic flux density, making it difficult for the motor output torque and efficiency to reach ideal levels.

[0005] 2. Insufficient heat dissipation: During motor operation, losses are generated in the windings and core (if any), which are converted into heat. The thermal conductivity of the PCB substrate itself is usually low, which is not conducive to the rapid dissipation of heat from the winding area. The accumulation of heat will cause the winding temperature to rise too high, affecting the insulation reliability, motor efficiency, and even causing the risk of magnet demagnetization, thus limiting the motor's continuous output capacity and power density.

[0006] Therefore, the current PCB winding axial flux motor technology field urgently needs an innovative solution that can comprehensively solve the above problems, that is, while maintaining the advantages of PCB winding technology (consistency, low cost), significantly improve the motor's torque density, operating efficiency and heat dissipation performance, and achieve a compact and simplified overall structure. Summary of the Invention

[0007] To address the problems in existing technologies where the lack of a highly efficient magnetic circuit structure in the PCB winding substrate leads to limited air gap magnetic flux density, making it difficult for the motor output torque and efficiency to reach ideal levels, and the difficulty in quickly dissipating heat from the substrate, thus affecting insulation reliability and electrical efficiency, a PCB winding axial flux motor with effective heat dissipation is proposed.

[0008] To address the above issues, a PCB winding axial flux motor is proposed, comprising a rotor, a housing, a stator, and a PCB winding board sleeved on the stator. Two sets of rotors are provided, with a bearing between the two sets of rotors, and a multi-layer PCB winding board is provided around the bearing along its axial direction. A heat dissipation interlayer is provided between two adjacent PCB winding boards for heat dissipation; The stator is embedded in the PCB winding board and heat dissipation sandwich layer; The heat dissipation interlayer surface is in contact with the PCB winding board surface and the stator side, transferring and dissipating the heat generated by the winding and stator.

[0009] Preferably, the stator includes multiple SMC stator cores evenly distributed around the bearing periphery; The PCB winding board is provided with winding holes corresponding to the SMC stator core; The heat dissipation interlayer is provided with slots corresponding to the SMC stator core and winding holes; Multiple SMC stator cores are embedded in winding holes and slots.

[0010] Preferably, the shape of the heat dissipation interlayer is matched with the shape of the middle PCB winding board of the multi-layer PCB winding board; The heat dissipation interlayer is made of aluminum nitride ceramic sheet.

[0011] Preferably, both sets of rotors include a rotor base and a plurality of permanent magnets disposed within the rotor base, the permanent magnets being evenly distributed along the central axis of the rotor base.

[0012] Preferably, a rotating shaft is provided at the center position of both sets of rotors, and a bearing housing is provided on the outer sleeve of the rotating shaft; The bearing housing is coaxially arranged with the PCB winding board and located on the outside of the PCB winding board; Both bearing housings are equipped with fixing posts for securing the PCB winding board and the heat dissipation interlayer.

[0013] Preferably, both the PCB winding board and the heat dissipation interlayer are provided with internal mounting holes, which are located on their inner edges and are set along their axis. The internal mounting holes are divided into two groups, and the position of the internal mounting holes in each group corresponds to the fixing post on each bearing housing. The fixing posts on the two bearing housings are installed through the inner mounting holes and misaligned on the fixing PCB winding board and heat dissipation interlayer to limit and fix them; External mounting holes are provided on the outer edges of the PCB winding board, heat dissipation interlayer, and housing for fixing with mounting parts.

[0014] Preferably, the bearing is disposed between two bearing housings.

[0015] Preferably, there are two housings, and the housings are connected to the PCB winding board.

[0016] Preferably, the PCB winding board near the housing is connected to the housing; The housing is provided with a slot for mounting the PCB winding board, and the shape of the PCB winding board is matched with the shape of the housing. After the PCB winding board is engaged with the housing, it forms a plane with the housing surface; The plane and the heat dissipation interlayer are the same size and shape.

[0017] Preferably, the housing is provided with an aluminum alloy heat dissipation edging, which contacts the outer edge surface of the PCB winding board to dissipate heat from the PCB winding board.

[0018] The beneficial effects of this invention; 1. This application uses a single stator and a single stator with dual rotor structure, which eliminates the stator yoke, saves materials, reduces core loss, and increases torque density.

[0019] 2. The PCB winding of this application is attached to the FR4 substrate, and the stator is an SMC stator core, which realizes a magnetic circuit structure with high efficiency and magnetic concentration; the SMC stator core is embedded in the PCB winding board, which improves the torque density and efficiency of the motor.

[0020] 3. Single bearing design, compact structure, and short axial dimension.

[0021] 4. Setting an aluminum nitride heat dissipation interlayer between the PCB winding boards can quickly and effectively conduct and dissipate the heat generated by the stator and windings, ensuring motor operating efficiency, reducing the risk of magnet demagnetization, and improving the motor's continuous output capability and power density. Attached Figure Description

[0022] Figure 1 This is a top view of the overall structure of the present invention; Figure 2 This is a bottom view of the overall structure of the present invention; Figure 3 This is a side view of the overall structure of the present invention; Figure 4 The PCB winding axial flux motor structure of this invention explodes. Figure 1 ; Figure 5 Explosion of the PCB winding axial flux motor structure in this invention Figure 2 ; Figure 6 Explosion of the PCB winding axial flux motor structure in this invention Figure 3 ; Figure 7 This is a schematic diagram of the outer PCB winding board in this invention.

[0023] In the diagram: Rotor 1, Rotor base 1-1, Permanent magnet 1-2, Shaft 1-3, Stator 2, Bearing seat 3, Fixing column 3-1, Bearing 4, PCB winding board 5, Outer PCB winding board 5-1, Inner PCB winding board 5-2, Winding hole 5-3, Heat dissipation interlayer 6, Slot 6-1, Housing 7, Inner mounting hole 8, Outer mounting hole 9. Detailed Implementation

[0024] The present invention will be further described below with reference to the accompanying drawings and embodiments: like Figure 1-7 As shown, a PCB winding axial flux motor includes a rotor 1, a housing 7, a stator 2, and a PCB winding board 5 sleeved on the stator 2. Two sets of rotors 1 are provided, and a bearing 4 is provided between the two sets of rotors 1. Multiple layers of PCB winding boards 5 are provided around the bearing 4 along its axial direction. A heat dissipation interlayer 6 is provided between two adjacent layers of PCB winding boards 5 for heat dissipation. The stator 2 is embedded in the PCB winding board 5 and the heat dissipation interlayer 6. The surface of the heat dissipation interlayer 6 contacts the surface of the PCB winding board 5 and the side of the stator 2 to transfer and dissipate the heat generated by the winding and the stator 2.

[0025] The stator 2 includes multiple SMC stator cores evenly distributed around the bearing 4; the PCB winding board 5 has winding holes 5-3 corresponding to the SMC stator cores; the heat dissipation interlayer 6 has slots 6-1 corresponding to the SMC stator cores and winding holes 5-3; the multiple SMC stator cores are embedded in the winding holes 5-3 and slots 6-1. The shape of the heat dissipation interlayer 6 matches the shape of the middle PCB winding board 5 of the multi-layer PCB winding board 5, and the heat dissipation interlayer 6 is an aluminum nitride ceramic sheet.

[0026] Both sets of rotors 1 include a rotor base 1-1 and multiple permanent magnets 1-2 disposed within the rotor base 1-1. The permanent magnets 1-2 are evenly distributed along the central axis of the rotor base 1-1. A rotating shaft 1-3 is disposed at the center of both sets of rotors 1, and a bearing seat 3 is disposed on the outer side of the rotating shaft 1-3. The bearing seat 3 is coaxially disposed with the PCB winding board 5 and is located outside the PCB winding board 5. Both bearing seats 3 are provided with fixing posts 3-1 for fixing the PCB winding board 5 and the heat dissipation interlayer 6. Both the PCB winding board 5 and the heat dissipation interlayer 6 are provided with internal mounting holes 8, which are located on their inner edges and along their axes. The internal mounting holes 8 are divided into two groups, and the position of each group of internal mounting holes 8 corresponds to the fixing post 3-1 on each bearing seat 3. The fixing posts 3-1 on the two bearing seats 3 pass through the internal mounting holes 8 and are installed in a staggered manner on the fixed PCB winding board 5 and the heat dissipation interlayer 6 to limit and fix them. The outer edges of the PCB winding board 5, the heat dissipation interlayer 6, and the housing 7 are all provided with external mounting holes 9, which are fixed by mounting parts. The bearing 4 is located between the two bearing seats 3.

[0027] Two housings 7 are provided, and each housing 7 is connected to the PCB winding board 5. The PCB winding board 5 closest to housing 7 is connected to housing 7; housing 7 is provided with a slot for mounting the PCB winding board 5, and the shape of the PCB winding board 5 matches the shape of housing 7; after the PCB winding board 5 is engaged with housing 7, it forms a plane with the surface of housing 7; the plane is the same size and shape as the heat dissipation interlayer 6. Housing 7 is provided with an aluminum alloy heat dissipation edging, which contacts the outer edge surface of the PCB winding board 5 to dissipate heat from the PCB winding board 5.

[0028] The housing 7 is provided with a slot. The outer PCB winding board 5-1 is based on the inner PCB winding board 5-2, with part of the outer edge cut off, leaving a protrusion that corresponds to the slot. The protrusion is inserted into the slot of the housing 7. The outer PCB winding board 5-1 and the outer surface of the housing 7 form a plane. The size and shape of this plane are the same as those of the inner PCB winding board 5-2.

[0029] In the most preferred embodiment, three PCB winding boards 5 are provided in this application. Figures 1-7 The following explanations will be based on a three-layer PCB winding board with two sets of heat dissipation sandwich layers.

[0030] Depending on the actual needs, the PCB winding board 5 can be set to two, four or more (not shown in the figure).

[0031] When the PCB winding board 5 is set to two sets, it only includes the PCB winding boards 5 on both sides, and a heat dissipation sandwich layer 6 is set in the middle of the PCB winding boards on both sides.

[0032] When the PCB winding board is configured with three or more sets, the PCB winding board 5 includes two outer PCB winding boards 5-1 and at least one inner PCB winding board 5-2; a heat dissipation interlayer 6 is provided between two adjacent layers of PCB winding boards 5; the outer PCB winding board 5-1 is close to the rotor 1, and the inner PCB winding board 5-2 is located between the two outer PCB winding boards 5-1; the two outer PCB winding boards 5-1 are respectively connected to two housings 7; the shape of the outer PCB winding board 5-1 matches the shape of the inner side of the housing 7, and after the outer PCB winding board 5-1 is engaged with the housing 7, it forms a plane with the surface of the housing 7; the plane is the same size and shape as the inner PCB winding board 5-2 and the heat dissipation interlayer 6. The housing 7 is provided with an aluminum alloy heat dissipation edging, which contacts the outer edge surface of the PCB winding board 5 to dissipate heat from the PCB winding board 5.

[0033] This application features a single stator 2 and dual rotors 1 structure, eliminating the stator yoke, saving materials, reducing core losses, and increasing torque density. The stator 2 uses an SMC stator core, which is embedded in the PCB winding board 5, improving the motor's torque density and efficiency. The single-bearing design is compact and has a short axial dimension. An aluminum nitride heat dissipation layer 6 is placed between the PCB winding boards 5, allowing for further bonding and fixation. This heat dissipation layer quickly and effectively dissipates heat generated by the stator 2 and windings, ensuring motor operating efficiency, reducing the risk of magnet demagnetization, and improving the motor's continuous output capability and power density.

Claims

1. A PCB winding axial flux motor, comprising a rotor, a housing, a stator, and a PCB winding board sleeved on the stator, characterized in that, Two sets of rotors are set up, and a bearing is set between the two sets of rotors. A multi-layer PCB winding board is set around the bearing along its axial direction. A heat dissipation interlayer is provided between two adjacent PCB winding boards for heat dissipation; The stator is embedded in the PCB winding board and heat dissipation sandwich layer; The heat dissipation interlayer surface is in contact with the PCB winding board surface and the stator side, transferring and dissipating the heat generated by the winding and stator.

2. The PCB winding axial flux motor according to claim 1, characterized in that, The stator consists of multiple SMC stator cores evenly distributed around the bearing. The PCB winding board is provided with winding holes corresponding to the SMC stator core; The heat dissipation interlayer is provided with slots corresponding to the SMC stator core and winding holes; Multiple SMC stator cores are embedded in winding holes and slots.

3. The PCB winding axial flux motor according to claim 1, characterized in that, The shape of the heat dissipation interlayer is matched with the shape of the middle PCB winding board of the multi-layer PCB winding board; The heat dissipation interlayer is made of aluminum nitride ceramic sheet.

4. The PCB winding axial flux motor according to claim 1, characterized in that, Both sets of rotors include a rotor base and multiple permanent magnets disposed within the rotor base. The permanent magnets are evenly distributed along the axial direction of the rotor base.

5. The PCB winding axial flux motor according to claim 4, characterized in that, A rotating shaft is installed at the center of both sets of rotors, and a bearing housing is fitted around the rotating shaft; The bearing housing is coaxially arranged with the PCB winding board and located on the outside of the PCB winding board; Both bearing housings are equipped with fixing posts for securing the PCB winding board and the heat dissipation interlayer.

6. The PCB winding axial flux motor according to claim 5, characterized in that, Both the PCB winding board and the heat dissipation interlayer are provided with internal mounting holes, which are located on their inner edges and are set along their axis. The internal mounting holes are divided into two groups, and the position of the internal mounting holes in each group corresponds to the fixing post on each bearing housing. The fixing posts on the two bearing housings are installed through the inner mounting holes and misaligned on the fixing PCB winding board and heat dissipation interlayer to limit and fix them; External mounting holes are provided on the outer edges of the PCB winding board, heat dissipation interlayer, and housing for fixing with mounting parts.

7. The PCB winding axial flux motor according to claim 4, characterized in that, The bearing is positioned between two bearing housings.

8. The PCB winding axial flux motor according to claim 1, characterized in that, Two housings are provided, and the housings are connected to the PCB winding board.

9. The PCB winding axial flux motor according to claim 8, characterized in that, The PCB winding board near the housing is connected to the housing; The housing is provided with a slot for mounting the PCB winding board, and the shape of the PCB winding board is matched with the shape of the housing. After the PCB winding board is engaged with the housing, it forms a plane with the housing surface; The plane and the heat dissipation interlayer are the same size and shape.

10. The PCB winding axial flux motor according to claim 9, characterized in that, The housing is provided with an aluminum alloy heat dissipation edging, which contacts the outer edge surface of the PCB winding board to dissipate heat from the PCB winding board.

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