Magnetic field controllable axial magnetic flux permanent magnet motor, assembly tool and assembly method

Abstract

The invention provides a magnetic field controllable axial magnetic flux permanent magnet motor, an assembly tool and an assembly method. A single-stator / double-rotor structure is adopted. The stator comprises Ps I-shaped stator iron cores, Ps flat wire coils and a stator bracket; mounting grooves which are distributed along the circumferential direction of the stator bracket and are used for mounting the stator units are formed in the stator bracket; and a water channel is formed in the stator bracket between two adjacent mounting grooves. Each rotor comprises Pr fan-shaped neodymium iron boron permanent magnets, Pr permanent magnet clamp springs and a rotor iron core. The stator and the rotor are coaxially installed through the connecting assembly. The motor provided by the invention adopts a variable-phase-number design, the loading capacity is flexible to adjust, the fault tolerance performance is good, and the reliability is high; due to the double-rotor axial topology, the structure is compact, and the torque pulsation is small; the water channel is large in heat exchange area, high in heat exchange efficiency and good in heat dissipation performance; the stator and the rotor are assembled in a progressive coaxial mode, assembling is safe and convenient, and air gap uniformity is good.

Description

Technical Field

[0001] The present invention belongs to the technical field of axial flux permanent magnet motors, and specifically relates to a magnetic field controllable axial flux permanent magnet motor, an assembly tool for the magnetic field controllable axial flux permanent magnet motor, and a magnetic field controllable axial flux permanent magnet motor assembly method. Background Art

[0002] With the continuous advancement of science and technology, the industrial sector has placed higher demands on motor size, weight, power / torque density, efficiency, torque output capacity, reliability, and adaptability. Axial flux permanent magnet motors, with their short axial length, compact structure, high power / torque density, and strong torque output capacity, have broad application prospects in aerospace, electric vehicles, and ship propulsion.

[0003] Traditional axial flux permanent magnet motors are limited by their unadjustable air gap magnetic field, making them difficult to adapt to complex operating conditions. Improved axial flux hybrid excitation motors, while capable of magnetic field regulation, suffer from limited adjustment range, low magnetic regulation efficiency, and increased copper losses due to continuous electrical excitation. Axial flux permanent magnet memory motors, while employing permanent magnet magnetization regulation, can reduce copper losses, but the space occupied by the pulse winding limits the electromagnetic load, thus affecting the motor's power and torque density.

[0004] In addition, the air gap magnetic field of the axial flux permanent magnet motor is distributed in a circumferential plane, the axial magnetic pull is large, and the air gap uniformity requirements are high. It is difficult to manufacture and assemble. The single stator / dual rotor topology stator has difficulty in heat dissipation and the thermal management capability is poor. Summary of the Invention

[0005] The purpose of the present invention is to solve the problems of the existing axial flux permanent magnet motor, such as insufficient flexibility in magnetic field adjustment, low magnetic adjustment efficiency, high loss, insufficient thermal management capability and difficult assembly, and to provide a magnetic field controllable axial flux permanent magnet motor, an assembly tool for a magnetic field controllable axial flux permanent magnet motor and a method for assembling a magnetic field controllable axial flux permanent magnet motor.

[0006] To achieve the above objectives, the technical solutions provided by the present invention are:

[0007] Provided is a magnetic field controllable axial flux permanent magnet motor, which includes a cylindrical casing, a stator and two rotors arranged in the cylindrical casing. The two rotors are coaxially mounted on both sides of the stator through a connecting assembly. An air gap is left between each rotor and the stator. Each rotor is fixedly connected to the inner wall of the cylindrical casing; each rotor includes P r A sector-shaped NdFeB permanent magnet, P rA permanent magnet retaining spring and a rotor core; each rotor core is provided with tooth poles and positioning slots staggered along its circumferential direction on the side facing the stator; the sector-shaped NdFeB permanent magnets are magnetized along the axial direction of the rotor, and the polarity is alternately attached to the tooth poles of the rotor core, and the permanent magnet retaining spring is embedded in the positioning slot to limit the axial position of the sector-shaped NdFeB permanent magnets; the stator includes P s I-type stator core, P s A flat wire coil and a stator bracket, the stator bracket has a first center hole; each flat wire coil is wound on a corresponding I-type stator core to form a stator unit; the stator bracket is provided with mounting slots distributed along its circumference, and a water channel is provided in the stator bracket between two adjacent mounting slots, the mounting slots are used to install the stator unit, and the water channel is used to dissipate heat from the stator unit; the number of I-type stator cores meets: P s =6k, the number of sector-shaped NdFeB permanent magnets meets: P r =P s ±2i, k and i are all positive integers; the connecting assembly includes a main shaft, a deep groove ball bearing, and a double-row angular contact bearing; the main shaft is installed in the first center hole on the inner wall of the stator bracket through the deep groove ball bearing and the double-row angular contact bearing, and the main shaft is fixedly connected to the center of one of the rotors; P s The flat wire coils are divided into six groups with equal magnetic potential and welded at the neutral point, and are divided into two sets of three-phase windings according to the principle of uniform distribution of armature reaction magnetic potential.

[0008] Furthermore, the two sets of three-phase windings are connected in series or in parallel, and each set of three-phase windings can be independently controlled by controlling the current.

[0009] Furthermore, the water channel is provided with two layers along the central axis of the stator bracket, each layer including an annular water trough provided on the inner wall of the stator bracket near the first central hole and a linear water channel provided radially along the stator bracket; one end of each linear water channel close to the center of the stator bracket is connected to the annular water trough, and the ends of the two linear water channels away from the center of the stator bracket are connected to each other; a bushing for sealing the annular water trough is installed on the inner wall of the first central hole of the stator bracket, and a bearing chamber for installing a double-row angular contact bearing is provided on the inner wall of the bushing; the ends of the two linear water channels away from the center of the stator bracket are sealed by a water channel cover plate.

[0010] Furthermore, each sector-shaped NdFeB permanent magnet is divided into five magnets along the radial direction, each magnet surface is coated with a ceramic layer, and each magnet is bonded to each other, and the radial width of the three middle magnets is consistent; clamping platforms are provided on both sides of the sector-shaped NdFeB permanent magnet, and the permanent magnet retaining spring cooperates with the clamping platform to limit the axial position of the sector-shaped NdFeB permanent magnet.

[0011] Furthermore, the I-type stator core is made of high saturation magnetic induction intensity iron-cobalt-vanadium soft magnetic alloy strips wound and laminated, and the surface is covered with a 3D-printed insulating frame, with wire outlet slots on both sides of the insulating frame.

[0012] Furthermore, a positioning boss is provided on the sector-shaped NdFeB permanent magnet, and a tooth pole on the iron core of the iron core rotor is provided with a positioning rubber groove that cooperates with the positioning boss.

[0013] Furthermore, the rotor further includes a rotor end cover; the main shaft is fixedly connected to one of the rotor end covers;

[0014] A fixing groove is provided at the inner diameter of the rotor end cover and is on the same radial line as the positioning groove, and the permanent magnet retaining spring is embedded in the fixing groove.

[0015] An assembly tool for a magnetic field controllable axial flux permanent magnet motor is also provided, which is used to assemble the above-mentioned magnetic field controllable axial flux permanent magnet motor, including a mounting base, a first fixed plate, a second fixed plate and a guide shaft; four through-thread screws are rotatably connected to the mounting base; the first fixed plate is used to install the stator bracket and is fixedly installed on the mounting base; the second fixed plate is connected to the upper side of the first fixed plate through four through-thread screws; the guide shaft can be sleeved on the main shaft.

[0016] A method for assembling a magnetic field controllable axial flux permanent magnet motor is also provided. The method comprises assembling the magnetic field controllable axial flux permanent magnet motor using the assembly tool, and comprising the following steps:

[0017] Step 1: Assemble the rotor;

[0018] Step 2: Assemble and pot the stator;

[0019] Step 3: Assemble the connection components and the stator:

[0020] Step 4: Assemble the rotor in step 1 with the connection assembly assembled in step 3; fix the assembled connection assembly vertically on the first fixing plate, then insert the guide shaft into one end of the main shaft, fix one of the rotors on the second fixing plate, then install the second fixing plate to the upper end of the threaded screw, and then install the lower end of the threaded screw to the mounting base. Multiple threaded screws are located outside the stator, and the second center hole of the rotor passes through the guide shaft; then control the multiple threaded screws to rotate synchronously so that the rotor approaches the stator below and is assembled to the corresponding position; then fix the cylindrical casing to the outer wall of the assembled rotor;

[0021] Step 5: Assemble the other rotor with the stator; flip the connecting assembly 180°, fix it vertically on the first fixed plate, insert the guide shaft into the other end of the main shaft, fix the other rotor on the second fixed plate, and then install the second fixed plate to the upper end of the threaded screw, and then install the lower end of the threaded screw to the mounting base. Multiple threaded screws are located on the outside of the stator, and the second center hole of the rotor passes through the guide shaft; then control the multiple threaded screws to rotate synchronously so that the rotor approaches the stator below and assembles it to the corresponding position so that the other end of the main shaft is fixedly connected to the center of the rotor, and then fix the rotor to the inner wall of the cylindrical casing assembly.

[0022] Furthermore, a deep groove ball bearing is installed on the main shaft, a double row angular contact bearing is installed on the inner side of the stator bracket, the main shaft passes through the inner diameter of the double row angular contact bearing and is installed on the stator bracket, and is fixed with a fastening nut to complete the assembly of the connection component and the stator.

[0023] The advantages of the present invention are:

[0024] 1. The magnetic field controllable axial flux permanent magnet motor designed by the present invention adopts a single stator / dual rotor axial topology, with short axial length, small size, compact structure, high power / torque density and strong torque output capability.

[0025] 2. In the magnetic field controllable axial flux permanent magnet motor designed by the present invention, the stator adopts two sets of three-phase windings with equal magnetic potential. By controlling the current in the three-phase winding, it is easy to realize flexible adjustment of the armature reaction magnetic potential and quickly reconstruct the air gap magnetic field, so that the axial flux permanent magnet motor can realize multiple working modes, and the operating state switching is smooth, with strong reliability and fault tolerance, and can adapt to the performance requirements such as torque output capacity and speed regulation range under different working conditions.

[0026] 3. The present invention provides a water channel on the stator bracket, which surrounds the I-type stator core and the flat wire coil, thereby improving the heat dissipation performance and thermal management capability of the axial flux permanent magnet motor.

[0027] 4. The assembly method of the magnetic field controllable axial flux permanent magnet motor designed by the present invention is simple and efficient. By cooperating the designed first fixing plate and second fixing plate with the threaded screw, the stator and rotor are assembled progressively and at one time using the threaded screw, thereby improving the air gap uniformity and assembly safety during assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The features and advantages of the present invention will become more readily understood through the following description with reference to the accompanying drawings, which are not drawn to scale and in which some features are exaggerated or minimized to show details of particular components.

[0029] Figure 1 This is a schematic diagram of the structure of the magnetic field controllable axial flux permanent magnet motor of the present invention;

[0030] Figure 2 This is a schematic diagram of the assembly of the iron core rotor iron core and the sector-shaped NdFeB permanent magnets in the present invention;

[0031] Figure 3 This is a schematic structural diagram of the stator bracket in the present invention:

[0032] Figure 4 This is a schematic diagram of the assembly of the stator bracket, waterway cover plate and waterway in the present invention;

[0033] Figure 5 This is a schematic diagram of a double-set three-phase winding of a magnetic field controllable axial flux permanent magnet motor according to the present invention;

[0034] Figure 6 This is a schematic diagram of the structure of the fan-shaped NdFeB permanent magnet of the present invention;

[0035] Figure 7 It is a structural schematic diagram of the stator unit in the present invention;

[0036] Figure 8 This is a schematic diagram of the positioning boss position on the fan-shaped NdFeB permanent magnet;

[0037] Figure 9 It is a structural schematic diagram of the iron core of the iron core rotor in the present invention;

[0038] Figure 10 It is a schematic structural diagram of the first rotor end cover in the present invention;

[0039] Figure 11 It is a structural schematic diagram of the second rotor end cover in the present invention;

[0040] Figure 12 This is a schematic diagram of the assembly of the complete permanent magnet motor with controllable magnetic field and axial flux according to the present invention;

[0041] Figure 13 This is a schematic diagram of stator varnish dipping and overall potting in the present invention;

[0042] Figure 14 It is a structural schematic diagram of the first potting tool in the present invention;

[0043] 1-first rotor; 2-stator; 3-second rotor; 4-sector-shaped NdFeB permanent magnet; 5-rotor core; 6-second rotor end cover; 7-first rotor end cover; 8-permanent magnet retaining spring; 9-stator core; 10-flat wire coil; 11-stator bracket; 12-water channel cover; 13-main shaft; 14-deep groove ball bearing; 15-double-row angular contact bearing; 16-cylindrical housing; 17-fastening nut; 18-insulating skeleton core; 19-water channel, 20-bushing; 21-first potting tool; 22-second potting tool; 23-third potting tool; 24-connecting assembly; 25-first fixing plate; 26-second fixing plate; 27-guide shaft; 28-threaded screw; 29-positioning boss; 30-rotor core positioning glue groove; 31-rotor core positioning groove; 32-fixing groove. DETAILED DESCRIPTION

[0044] The present invention will be described in detail below with reference to the accompanying drawings by means of exemplary embodiments of the present invention. It should be noted that the following detailed description of the present invention is only for the purpose of illustration and is not intended to limit the present invention.

[0045] like Figure 1 As shown, the present invention provides a magnetic field controllable axial flux permanent magnet motor, which includes a cylindrical housing 16, a stator 2 and two rotors arranged in the cylindrical housing 16. The two rotors are coaxially mounted on both sides of the stator 2 through a connecting assembly 24. An air gap is left between each rotor and the stator 2, and each rotor is fixedly connected to the inner wall of the cylindrical housing 16; Figure 1 As shown, the rotor includes a first rotor 1 located on the left and a second rotor 3 located on the right.

[0046] like Figure 1 、 2 As shown, each rotor includes P r 4 sector-shaped NdFeB permanent magnets, P r A permanent magnet retaining spring 8 and a rotor core 5; each rotor core 5 is provided with tooth poles and positioning grooves 31 that are staggered in sequence along its circumferential direction on the side facing the stator 2; the sector-shaped NdFeB permanent magnets 4 are magnetized along the axial direction of the first rotor 1, and are alternately attached to the tooth poles of the rotor core 5 with alternating polarity. The permanent magnet retaining spring 8 is embedded in the positioning groove 31 to limit the axial position of the sector-shaped NdFeB permanent magnet 4.

[0047] like Figure 1 、 3 As shown in 4, the stator 2 includes P s I-type stator core 9, P sA flat wire coil 10 and a stator bracket 11, the stator bracket 11 has a first center hole; each flat wire coil 10 is wound on the corresponding I-type stator core 9 to form a stator unit; the stator bracket 11 is provided with mounting grooves distributed along its circumference, and a water channel 19 is provided in the stator bracket 11 between two adjacent mounting grooves. The mounting groove is used to install the stator unit, and the water channel 19 is used to dissipate heat from the stator unit; the number of the 9 I-type stator cores meets: P s =6k, the number of sector-shaped NdFeB permanent magnets 4 satisfies: P r =P s ±2i, k and i are both positive integers.

[0048] like Figure 1 As shown, the connecting assembly 24 includes a main shaft 13, a deep groove ball bearing 14 and a double row angular contact bearing 15; the main shaft 13 is installed in the first center hole on the inner wall of the stator bracket 11 through the deep groove ball bearing 14 and the double row angular contact bearing 15, and the main shaft 13 is fixedly connected to the center of the second rotor 3.

[0049] like Figure 5 As shown, P s The flat wire coils 10 are divided into six groups with equal magnetic potential and welded at the neutral point, and are divided into two sets of three-phase windings according to the principle of uniform distribution of armature reaction magnetic potential.

[0050] In this embodiment, each rotor is provided with twenty sector-shaped NdFeB permanent magnets 4 and twenty permanent magnet retaining springs 8, and the stator 2 is provided with eighteen I-type stator cores 9 and eighteen flat wire coils 10. The eighteen flat wire coils 10 are divided into six groups with equal magnetic potential and welded to the neutral point.

[0051] The magnetic field controllable axial flux permanent magnet motor designed in this embodiment adopts a single stator / dual rotor axial topology. The stator 2 and the rotor are both disc structures with a short main magnetic circuit, which improves the power / torque density and magnetic field utilization of the permanent magnet motor. It has a short axial length, a small volume, a compact structure, a high power / torque density, and a strong torque output capacity. The stator 2 adopts two sets of three-phase windings with equal magnetic potential. By controlling the current in the three-phase winding, it is easy to achieve flexible adjustment of the armature reaction magnetic potential and quickly reconstruct the air gap magnetic field, so that the axial flux permanent magnet motor can achieve multiple working modes, and the operating state switching is smooth, with strong reliability and fault tolerance, and can adapt to the performance requirements such as torque output capacity and speed regulation range under different working conditions. A water channel 19 is provided on the stator bracket 11. The water channel 19 surrounds the I-type stator core 9 and the flat wire coil 10, thereby improving the heat dissipation performance and thermal management capability of the axial flux permanent magnet motor.

[0052] like Figure 5As shown, two sets of three-phase windings are connected in series or in parallel, and each set can be independently controlled by controlling the current. This allows for flexible configuration of the permanent magnet motor's electrical load, efficient air gap magnetic field regulation, and smooth operating state switching, enabling the motor to operate in five operating modes: single three-phase operation, dual three-phase operation, six-phase operation, three-phase AC hybrid excitation operation, and backup fault-tolerant operation. It can switch quickly and smoothly between five operating modes: single three-phase, dual three-phase, six-phase, AC hybrid excitation and backup fault tolerance. It operates in single three-phase mode at low load to reduce energy consumption and heat dissipation system pressure; it works in dual three-phase mode at high load and has strong torque output capacity; the six-phase mode can effectively suppress the armature reaction magnetic field harmonics, with small torque pulsation, smooth torque output, strong stability and comfort; it works in AC hybrid excitation mode when frequent speed and load changes are required, with high magnetic regulation efficiency and flexible air gap magnetic field changes, which greatly widens the motor speed regulation range and improves load capacity; it operates in backup fault tolerance mode when the working environment is complex. When one or more phase windings fail, the backup phase winding is enabled to quickly reconstruct the air gap magnetic field and improve the operation reliability of the permanent magnet motor.

[0053] like Figure 3 、 4 As shown, the water channel 19 is provided in two layers along the central axis of the stator support 11. Each layer includes an annular water trough provided on the inner wall of the stator support 11 near the first central hole and a linear water channel provided radially along the stator support 11. The end of each linear water channel near the center of the stator support 11 is connected to the annular water trough, and the ends of the two linear water channels away from the center of the stator support 11 are connected to each other. A bushing 20 for sealing the annular water trough is installed on the inner wall of the first central hole of the stator support 11. The inner wall of the bushing 20 is provided with a bearing chamber for mounting a double-row angular contact bearing 15. The ends of the two linear water channels away from the center of the stator support 11 are sealed by a water channel cover plate 12.

[0054] A double-layer circulating water channel 19 is set in the stator bracket 11, which has low water resistance and high circulation efficiency; the water channel 19 penetrates into the stator unit composed of the flat wire coil 10 and the I-type stator core 9, with a short heat transfer path, good heat dissipation performance of the permanent magnet motor, and strong thermal management capability. The annular water tank is sealed with a bushing 20, and the bushing 20 leaves a bearing chamber. Eighteen water channel covers 12 are installed on the stator bracket 11 with screws. The water channel cover 12 and the bushing 20 seal the water channel 19. A sealing ring is pressed under the water channel cover 12 to prevent coolant leakage; the shaft end of the stator bracket 11, such as Figure 4 The top surface of the stator bracket 11 shown is provided with a water interface for water inlet and outlet.

[0055] like Figure 6As shown, each sector-shaped NdFeB permanent magnet 4 is radially divided into five magnets. Each magnet is coated with a ceramic layer and bonded to each other. The three central magnets have the same radial width. Clamps are located on either side of the sector-shaped NdFeB permanent magnet 4. Permanent magnet retaining springs 8 cooperate with the clamps to restrict the axial position of the sector-shaped NdFeB permanent magnet 4. The three central magnets are wider, while the two peripheral magnets are narrower. This reduces the impact of edge and bending effects on the main magnetic circuit, while the unequal division of the magnets ensures a uniform distribution of the air gap magnetic field. A thin ceramic coating is applied between each small magnet, reducing its impact on the motor's magnetic load. This provides excellent insulation, significantly reducing the eddy current density of the permanent magnets and thereby suppressing eddy current losses. Clamps are located on the edges of the permanent magnets. The permanent magnet retaining springs 8 and the clamps cooperate to restrict the axial position of the sector-shaped NdFeB permanent magnet 4, improving the reliability and safety of the motor.

[0056] like Figure 7 As shown, the I-type stator core 9 is made of high saturation magnetic induction intensity iron-cobalt-vanadium soft magnetic alloy strips wound and laminated, and the surface is covered with a 3D-printed insulating skeleton 18, and wire outlet slots are left on both sides of the insulating skeleton 18. The I-type stator core 9 is made of high saturation magnetic induction intensity iron-cobalt-vanadium soft magnetic alloy, with large saturation magnetic flux and low loss, which effectively improves the power / torque density and efficiency of the permanent magnet motor. The I-type stator core 9 is covered with a 3D-printed insulating skeleton 18, which improves the insulation strength while limiting the axial displacement of the coil, improves the slot fill rate and winding efficiency, improves manufacturing efficiency, and reduces assembly difficulty. According to the shape and size of the I-type stator core 9, the insulating skeleton 18 is manufactured using 3D printing technology and coated on the stator core 9, which is easy to process. The insulating skeleton 18 is thin and has good insulation effect, reducing the risk of voltage breakdown between the winding and the I-type stator core 9. The flat wire coil 10 is wound in four layers on the I-type stator core 9 in a flat winding manner, which maximizes the slot fill rate, has low thermal resistance in the heat transfer direction, facilitates heat dissipation, and improves the thermal management capability of the permanent magnet motor. In addition, wire outlet slots are set on both sides of the insulating frame 18 to facilitate the outlet of the flat wire coil 10. Figure 8 、 9 As shown, the sector-shaped NdFeB permanent magnets 4 are provided with positioning bosses 29, and the teeth on the core rotor core 5 are provided with positioning rubber grooves 30 that cooperate with the positioning bosses 29. The positioning rubber grooves 30 provided on each tooth of the core rotor core 5 cooperate with the positioning bosses 29 provided on the sector-shaped NdFeB permanent magnets 4, making the sector-shaped NdFeB permanent magnets 4 easy to install and achieving high circumferential positioning accuracy, thereby improving the uniformity of the axial magnetic field distribution in the air gap.

[0057] like Figure 1 、 10As shown in Figure 11, the rotor also includes a rotor end cover, and the iron core rotor core 5 is fixed on the rotor end cover; the rotor end cover includes a first rotor end cover 7 on the first rotor 1 and a second rotor end cover 6 on the second rotor 3, and the main shaft 13 is fixedly connected to the second rotor end cover 6; the first rotor end cover 7 has a larger inner diameter, which is convenient for leading out the mechanical interface, water interface and electrical interface of the stator, and the second rotor end cover 6 needs to be fixed with the main shaft 13, so the inner diameter is smaller.

[0058] The first rotor end cover 7 and the second rotor end cover 6 are both provided with a fixing groove 32 on the same radial line as the positioning groove 31 and a semicircular hole for glue injection at the inner diameter. The permanent magnet retaining spring 8 is embedded in the fixing groove 32. The axial position of the fan-shaped NdFeB permanent magnet 4 is limited by the mutual cooperation of the clamping platform of the fan-shaped NdFeB permanent magnet 4, the permanent magnet retaining spring 8 and the rotor end cover.

[0059] Also provided is an assembly tool for a magnetic field controllable axial flux permanent magnet motor, which is used to assemble the above-mentioned magnetic field controllable axial flux permanent magnet motor. Figure 12 As shown, it includes a mounting base, a first fixing plate 25, a second fixing plate 26 and a guide shaft 27; four through-thread screws 28 are rotatably connected to the mounting base; the first fixing plate 25 is used to install the stator bracket 11, and is fixedly installed on the mounting base. The first fixing plate 25 is provided with a first threaded hole for matching with the plane of the stator bracket 11; the second fixing plate 26 is connected to the upper side of the first fixing plate 25 through four through-thread screws 28, and a second threaded hole matching with the through-thread screw 28 is provided on the edge of the plane; the guide shaft 27 can be sleeved on the main shaft 13.

[0060] A method for assembling a permanent magnet motor with controllable magnetic field and axial flux is also provided. The method comprises assembling the permanent magnet motor using the assembly tool, and comprising the following steps:

[0061] Step 1: Assemble the first rotor 1 and the second rotor 3 separately;

[0062] The fan-shaped NdFeB permanent magnets 4 are surface-mounted on the tooth poles of the rotor core 5. The permanent magnet retaining springs 8 are inserted along the fixing slots 32 of the first rotor end cap 7 and the positioning slots 31 of the rotor core 5. The two wings of the permanent magnet retaining springs 8 press against the clamping platform of the adjacent fan-shaped NdFeB permanent magnets 4 of the rotor core. Glue is injected through the semicircular hole on the outer diameter of the first rotor end cap 7 to secure the permanent magnet retaining springs 8. The permanent magnet retaining springs 8 are then glued into the positioning slots 31 of the rotor core 5. The first rotor 1 is successfully assembled. The second rotor 3 is assembled in the same manner as the first rotor 1.

[0063] Step 2: Assemble and pot the stator 2;

[0064] Wrap the insulating frame 18 on the I-type stator core 9, and wind the flat wire coil 10 in four layers along the tooth poles of the I-type stator core 9 to form a stator unit; and install multiple stator units into the corresponding mounting grooves of the stator bracket 11, install the bushing 20 into the inner wall of the stator bracket 11, seal the inner side of the water channel 19, and fix the water channel cover 12 on the stator bracket 11 with screws to seal the outer side of the water channel 19 and prevent the stator unit from slipping out, thereby completing the assembly of the stator 2.

[0065] like Figure 13 、 14 As shown, the potting uses a first potting tool 21, a second potting tool 22 and a third potting tool 23; the first potting tool 21 is a hollow barrel structure, and the bottom of the first potting tool 21 is provided with grooves corresponding to the stator units one by one; the second potting tool 22 is a ring structure with an opening at one end, and the diameter of the opening of the second potting tool 22 is larger than the diameter of the upper end of the stator bracket 11; the third potting tool 23 is a circular plate structure, and its radius is larger than the first center hole of the stator bracket 11 and smaller than the diameter of the opening of the second potting tool 22.

[0066] When potting, if Figure 14 As shown, the stator 2 is dipped in insulating paint as a whole and then installed in the first potting tool 21. The lower end of the stator unit is installed in the groove at the bottom of the first potting tool 21, and the upper end of the stator unit is pressed by the second potting tool 22. The upper end of the first potting tool 21 and the lower end of the second potting tool 22 are fixedly connected by screws, so that the flatness of both sides of the I-type stator core 9 is high, the consistency of the air gap on both sides is ensured, the axial magnetic pull of the rotor on both sides is balanced, and the torque pulsation of the permanent magnet motor is reduced; the upper end of the stator bracket 11 is pressed by the third potting tool 23, and the third potting tool 23 is fixedly connected to the first potting tool 21 with screws to ensure the axial position of the stator 2. The potting tool is not removed after the insulating paint is cured, and then potting is performed immediately after the insulating paint is cured.

[0067] The stator 2 of this embodiment is integrally dipped in paint and potted at one time, and is simple and convenient to manufacture.

[0068] Step 3: Assemble the connecting component 24 and the stator 2:

[0069] Install the deep groove ball bearing 14 on the main shaft 13, install the double row angular contact bearing 15 on the inner side of the stator bracket 11, and install the main shaft 13 on the stator bracket 11 through the inner diameter of the double row angular contact bearing 15. Secure it with the fastening nut 17 to complete the assembly of the connecting assembly 24 and the stator 2.

[0070] Step 4: Assemble the first rotor 1 with the connecting assembly 24 assembled in step 3;

[0071] The assembled connecting assembly 24 is fixed vertically to the first fixing plate 25. The guide shaft 27 is then inserted into one end of the main shaft 13. The first rotor 1 is fixed to the second fixing plate 26. The second fixing plate 26 is then mounted to the upper end of the threaded screw 28. The lower end of the threaded screw 28 is then mounted to the mounting base. Multiple threaded screws 28 are located outside the stator 2, and the second center hole of the first rotor 1 passes through the guide shaft 27. The multiple threaded screws 28 are then controlled to rotate synchronously, so that the second fixing plate 26 drives the first rotor 1 toward the stator 2 below and assembles it to the corresponding position. The cylindrical casing 16 is then fixed to the outer wall of the assembled rotor.

[0072] Step 5: Assemble the second rotor 3 and the stator 2;

[0073] Flip the connecting assembly 24 180° and fix it vertically on the first fixing plate 25, insert the guide shaft 27 into the other end of the main shaft 13, fix the second rotor 3 on the second fixing plate 26, then install the second fixing plate 26 to the upper end of the threaded screw 28, and then install the lower end of the threaded screw 28 to the mounting base. Multiple threaded screws 28 are located on the outside of the stator 2, and the second center hole of the second rotor 3 passes through the guide shaft 27; then control the multiple threaded screws 28 to rotate synchronously, so that the second fixing plate 26 drives the second rotor 3 to approach the stator 2 below and assemble it to the corresponding position, so that the other end of the main shaft 13 is fixedly connected to the center of the second rotor end cover 6 of the second rotor 3, and then fix the rotor to the assembly inner wall of the cylindrical casing 16.

[0074] The assembly method of the magnetic field controllable axial flux permanent magnet motor designed in this embodiment is simple and efficient. The stator winding adopts an integral varnishing process. The eighteen stator units consisting of an I-type stator core 9, an insulating frame 18 and a flat wire coil 10 are installed in the stator bracket 11, and are fixed with a varnishing tool and then varnished as a whole. The varnishing efficiency is high and the difficulty is low. The potting glue has a low curing shrinkage rate characteristic, which avoids the negative influence of internal stress on the magnetic permeability of the soft magnetic alloy. By designing the first fixing plate 25, the second fixing plate 26 and the threaded screw 28, the stator and the rotor are assembled progressively and one-time using the threaded screw 28. This assembly method can effectively ensure the uniformity of the air gap and the consistency of the air gap on both sides, and has high assembly efficiency and good safety.

[0075] The present invention provides a magnetic field controllable axial flux permanent magnet motor, assembly tooling and assembly method, which solve the problems of existing axial flux permanent magnet motors such as insufficient flexibility in magnetic field adjustment, low magnetic adjustment efficiency, high loss, insufficient thermal management capability, and difficulty in manufacturing and assembly. It realizes high-efficiency and high-power / torque density operation of the motor, improves the working reliability and adaptability of the motor, and improves the manufacturing and assembly process, reduces the difficulty of manufacturing and assembly, and enhances manufacturing accuracy and assembly safety. The assembly method and its assembly tooling structure greatly improve the manufacturing and assembly efficiency, and have high assembly accuracy, good air gap uniformity and consistency.

[0076] Finally, it should be noted that the features mentioned and / or illustrated in the above description of the exemplary embodiments of the present invention may be incorporated into one or more other embodiments in the same or similar manner, combined with features in other embodiments, or substituted for corresponding features in other implementations. The technical solutions obtained by such combination or substitution shall also be deemed to be included in the scope of protection of the present invention.

Claims

1. A magnetic field controllable axial flux permanent magnet motor, characterized in that: The permanent magnet motor comprises a cylindrical housing (16), a stator (2) and two rotors arranged in the cylindrical housing (16), the two rotors being coaxially mounted on both sides of the stator (2) via a connecting assembly (24), an air gap being left between each rotor and the stator (2), and each rotor being fixedly connected to the inner wall of the cylindrical housing (16); Each of the rotors includes P r Sector-shaped NdFeB permanent magnets (4), P r a permanent magnet retaining spring (8) and a rotor core (5); Each rotor core (5) is provided with tooth poles and positioning slots (31) staggeredly distributed in sequence along its circumferential direction on one side facing the stator (2); the sector-shaped NdFeB permanent magnets (4) are magnetized along the axial direction of the rotor, and are alternately attached to the tooth poles of the rotor core (5); the permanent magnet retaining springs (8) are embedded in the positioning slots (31) to limit the axial position of the sector-shaped NdFeB permanent magnets (4); The stator (2) includes P s I-type stator core (9), P s A flat wire coil (10) and a stator bracket (11), wherein the stator bracket (11) has a first central hole; each flat wire coil (10) is wound on the corresponding I-type stator core (9) to form a stator unit; the stator bracket (11) is provided with mounting grooves distributed along its circumference, and a water channel (19) is provided in the stator bracket (11) between two adjacent mounting grooves, wherein the mounting groove is used to mount the stator unit, and the water channel (19) is used to dissipate heat from the stator unit; wherein the number of the I-type stator cores (9) satisfies: P s =6k, the number of the fan-shaped NdFeB permanent magnets (4) satisfies: P r =P s ±2i, k and i are both positive integers; The connecting assembly (24) includes a main shaft (13), a deep groove ball bearing (14) and a double row angular contact bearing (15); the main shaft (13) is installed in a first center hole on the inner wall of the stator bracket (11) through the deep groove ball bearing (14) and the double row angular contact bearing (15), and the main shaft (13) is fixedly connected to the center of one of the rotors; P s The flat wire coils (10) are divided into six groups with equal magnetic potential and welded to neutral points, and are divided into two sets of three-phase windings according to the principle of uniform distribution of armature reaction magnetic potential.

2. The magnetic field controllable axial flux permanent magnet motor according to claim 1, characterized in that: The two sets of three-phase windings are connected in series or in parallel, and each set of three-phase windings can be independently controlled by controlling the current.

3. The magnetic field controllable axial flux permanent magnet motor according to claim 1, characterized in that: The water channel (19) is provided with two layers along the central axis of the stator support (11), and each layer includes an annular water groove provided on the inner wall of the stator support (11) near the first central hole and a linear water channel provided radially along the stator support (11); one end of each linear water channel close to the center of the stator support (11) is connected to the annular water groove, and one end of the two linear water channels away from the center of the stator support (11) is connected to each other; A bushing (20) for sealing the annular water trough is installed on the inner wall of the first central hole of the stator bracket (11), and a bearing chamber for installing the double-row angular contact bearing (15) is provided on the inner wall of the bushing (20); one end of the two linear water channels away from the center of the stator bracket (11) is sealed by a water channel cover plate (12).

4. The magnetic field controllable axial flux permanent magnet motor according to claim 1, characterized in that: Each of the fan-shaped NdFeB permanent magnets (4) is divided into five magnets along the radial direction, each magnet surface is plated with a ceramic layer, and each magnet is bonded to each other, and the radial widths of the three middle magnets are consistent; clamping platforms are provided on both sides of the fan-shaped NdFeB permanent magnet (4), and the permanent magnet retaining spring (8) cooperates with the clamping platform to limit the axial position of the fan-shaped NdFeB permanent magnet (4).

5. The magnetic field controllable axial flux permanent magnet motor according to claim 1, characterized in that: The I-type stator core (9) is formed by winding and laminating high saturation magnetic induction intensity iron-cobalt-vanadium soft magnetic alloy strips, and the surface is covered with a 3D-printed insulation frame (18), and both sides of the insulation frame (18) are provided with wire outlet slots.

6. The magnetic field controllable axial flux permanent magnet motor according to claim 1, characterized in that: The sector-shaped NdFeB permanent magnet (4) is provided with a positioning boss (29), and the tooth poles on the iron core rotor core (5) are provided with a positioning glue groove (30) that matches the positioning boss (29).

7. The magnetic field controllable axial flux permanent magnet motor according to claim 1, characterized in that: The rotor (1) further comprises a rotor end cover; The main shaft (13) is fixedly connected to one of the rotor end covers; A fixing groove (32) located on the same radial line as the positioning groove (31) is provided at the inner diameter of the rotor end cover, and the permanent magnet retaining spring (8) is embedded in the fixing groove (32).

8. An assembly tool for a magnetic field controllable axial flux permanent magnet motor, used for assembling the magnetic field controllable axial flux permanent magnet motor according to any one of claims 1 to 7, characterized in that: include: A mounting base, wherein four threaded screws (28) are rotatably connected to the mounting base; A first fixing plate (25) is used for mounting the stator bracket (11) and is fixedly mounted on the mounting base; A second fixing plate (26) is connected to the upper side of the first fixing plate (25) through four threaded screws (28); The guide shaft (27) can be sleeved on the main shaft (13).

9. A method for assembling a magnetic field controllable axial flux permanent magnet motor, comprising assembling the magnetic field controllable axial flux permanent magnet motor according to any one of claims 1 to 7 using the assembly tool according to claim 8, wherein: The following steps are involved: Step 1: Assemble the rotor; Step 2: Assembling and potting the stator (2); Step 3: Assemble the connecting assembly (24) and the stator (2): Step 4: Assemble the rotor in step 1 with the connecting assembly (24) assembled in step 3; The assembled connecting assembly (24) is fixed vertically on the first fixing plate (25), and then the guide shaft (27) is inserted into one end of the main shaft (13), and one of the rotors is fixed on the second fixing plate (26), and then the second fixing plate (26) is installed to the upper end of the threaded screw (28), and then the lower end of the threaded screw (28) is installed to the mounting base, and multiple threaded screws (28) are located outside the stator (2), and the second center hole of the rotor passes through the guide shaft (27); then the multiple threaded screws (28) are controlled to rotate synchronously, so that the rotor approaches the stator (2) below and is assembled to the corresponding position; then the cylindrical housing (16) is fixedly installed on the outer wall of the assembled rotor; Step 5: Assemble the other rotor with the stator (2); The connecting assembly (24) is flipped 180 degrees and fixed vertically on the first fixing plate (25), the guide shaft (27) is inserted into the other end of the main shaft (13), and the other rotor is fixed on the second fixing plate (26), and then the second fixing plate (26) is installed to the upper end of the threaded screw (28), and then the lower end of the threaded screw (28) is installed to the mounting base, multiple threaded screws (28) are located outside the stator (2), and the second center hole of the rotor passes through the guide shaft (27); then the multiple threaded screws (28) are controlled to rotate synchronously, so that the rotor approaches the stator (2) below and is assembled to the corresponding position, so that the other end of the main shaft (13) is fixedly connected to the center of the rotor, and then the rotor is fixedly installed on the inner wall of the cylindrical casing (16).

10. The method for assembling a magnetic field controllable axial flux permanent magnet motor according to claim 9, characterized in that: The deep groove ball bearing (14) is mounted on the main shaft (13), and the double row angular contact bearing (15) is mounted on the inner side of the stator bracket (11). The main shaft (13) passes through the inner diameter of the double row angular contact bearing (15) and is mounted on the stator bracket (11). The main shaft (13) is fixed with a fastening nut (17), thereby completing the assembly of the connecting component (24) and the stator (2).

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