Fan-shaped magnetic steel fixing disc of axial magnetic field motor

Abstract

The utility model discloses a fan-shaped magnetic steel fixing disc of an axial magnetic field motor, and relates to the technical field of axial magnetic flux motors. The rotor comprises two rotor discs which are symmetrically installed face to face, a stator core is installed in the middle of each rotor disc, and each rotor disc is sequentially provided with a rotor fixing disc, a silicon steel disc, magnetic steel, a dovetail pressing plate, a notch in the rotor disc and the dovetail pressing plate in cooperation with external force to enable the pressing plate to expand so as to achieve the effect of the pressing plate. The axial direction and the radial direction of the magnetic steel are effectively fixed, the problem that the magnetic steel falls off under the condition of high-speed operation of the motor is solved, high-strength magnetic conductive materials are selected, eddy current is effectively reduced, loss is effectively reduced, temperature rise is reduced, the safety in operation is improved, structural components are simple, and the installation process is simplified.

Description

Technical Field

[0001] The utility model relates to the technical field of axial flux motors, and particularly relates to a sector magnet fixing disk for an axial magnetic field motor. Background Technique

[0002] Axial flux motors are a new type of motor technology. Under the same volume, axial flux motors have the advantages of being more structurally compact, having a stronger magnetic field, a higher power density, and a higher output power compared to ordinary motors. There are also many types of extended structures for axial magnetic field motors. Among them, the single-stator single-rotor structure and the single-rotor double-stator structure are more common, while the double-rotor single-stator structure is less common and has a higher process difficulty. The torque of an axial flux motor is in a proportional multiple relationship with the outer diameter of the motor. Therefore, it has a strong torque density in a disk-shaped structure. With the continuous maturity of technology, the application of axial flux motors is gradually expanding to scenarios such as electric vehicles, electric motorcycles, electric aircraft, wind power generation, ships, and robots. Compared with radial motors, the difference in axial flux motors is that the outer diameters of the rotor and the stator are the same. As the outer diameter of the internal electromagnetic region increases, the moment of inertia of the rotor also increases. Its permanent magnets are generally of a surface-mounted structure and an embedded rotor disk structure. For high-power and high-torque axial magnetic fields, the magnet grade is relatively high. When the motor is stationary, there is a strong suction force between the magnets and the stator iron core axially. When the motor is running, the electromagnetic suction force of the stator is also superimposed. The traditional magnetic steel structure bonding can no longer meet the actual requirements. Especially in the case of uneven air gaps, the axial balance will increase. Therefore, the fixation and protection of the magnets are a great test.

[0003] Patent CN111010008A discloses a rotor disk for fixing permanent magnets of an axial motor, which adopts a fixing method of a pressing plate and screws. Through a permanent magnet fixing frame and an externally wound glass fiber wire, it is finally integrated onto the rotor support plate to form a rotor assembly. However, in this way, there must be enough space between the permanent magnets for the installation of the pressing plate and the fixing of the bolts, and it is only suitable for occasions with relatively small axial suction force. When the volume of the permanent magnets is large and the distance between the permanent magnets is small, the pressing force exerted by the bolts is insufficient.

[0004] Patent CN101860098A discloses a rotor of a disk-type permanent magnet motor, which uses designed corresponding pressing blocks and screws to fix the permanent magnets to the motor metal magnetic shielding plate, so that the permanent magnets are firmly connected to the motor metal magnetic shielding plate. However, this method cannot guarantee the integrity of the permanent magnet structure during the operation process, and stress concentration will occur at the fastening connection part during high-speed rotation, and there will be a certain risk to the strength of the rotor permanent magnets. Content of the Utility Model

[0005] The purpose of the utility model is to provide a sector magnet fixing disk for an axial magnetic field motor to solve the problems raised in the above background technique.

[0006] To solve the above technical problems, the present utility model provides the following technical solution: A sector magnet fixing disk for an axial magnetic field motor, comprising a first rotor disk and a second rotor disk symmetrically installed face to face on a rotating shaft. The stator assembly is installed at a position spaced from the center of the first rotor disk. A silicon steel disk, a dovetail pressing plate, and magnets are installed at the inner opening of the annular groove on the first rotor disk.

[0007] An annular groove is formed in the rotor disk. The rotor silicon steel disk is installed in the annular groove of the first rotor disk. The dovetail pressing plates are evenly distributed in a radial shape and cooperate with the first rotor disk. The magnets are arranged in a reverse trapezoidal cross pattern and evenly distributed in the annular groove of the first rotor disk. The thickness of the magnets is half the distance higher than that of the dovetail pressing plates. Steel pins with a diameter larger than the diameter of the through holes on the pressing plates are installed inward from the radial uniform distribution, causing the cross section of the dovetail pressing plate to deform into a reverse trapezoid and press-fitting with the magnets to be fixed in the axial position of the first rotor disk.

[0008] Preferably, the magnets are in a sector shape, and the inner and outer arc sizes are equal to the inner annular groove opening of the first rotor disk. Fixed-angle draft angles are made on both sides of the magnets, and the thickness of the magnets is equal to the depth of the annular groove of the first rotor disk.

[0009] Preferably, the silicon steel disk is in an annular disk shape and is made by winding an iron core. The inner and outer circles have the same inner and outer diameters as the annular groove of the first rotor disk, and the thickness of the silicon steel disk is half the depth of the annular groove of the first rotor disk.

[0010] Preferably, the first rotor disk is in a disk claw shape. The annular groove has the same inner and outer diameters as the silicon steel disk and the magnets. The circular groove on the inner circle of the annular groove cooperates with the cylinder on the dovetail pressing plate, and the reverse trapezoidal groove opening on the outer circle of the annular groove cooperates with the dovetail end of the dovetail pressing plate. Four countersunk holes and four threaded holes in the middle of the first rotor disk are connected to the rotating shaft and the second rotor disk through bolts to form a rotor assembly.

[0011] Preferably, one end of the dovetail pressing plate is in a cylindrical shape, and the other end is in a trapezoidal shape. The middle trapezoidal cross section gradually changes to connect the two ends. There are gaps with through holes and split holes in the middle of the dovetail pressing plate. The cylindrical section of the dovetail pressing plate is connected to the circular groove on the inner circle of the annular groove of the first rotor disk. The trapezoidal section of the dovetail pressing plate cooperates with the trapezoidal groove on the outer edge of the annular groove of the rotor disk. The two side faces of the dovetail pressing plate cooperate with the two side faces of the magnets. Steel pins are inserted into the middle holes of the dovetail pressing plate radially, causing the dovetail pressing plate to deform and press-fitting with the magnets for fixation.

[0012] The beneficial effects of the present utility model are as follows: The axial and radial directions of the magnets are effectively fixed, solving the problem of magnet detachment during the high-speed operation of the motor. The present utility model selects high-strength magnetic conductive materials, which can effectively reduce eddy currents, reduce losses, lower temperature rise, and improve the safety during operation. The structure of this magnet fixing disk has simple components, and the installation process is also more convenient. Description of the Drawings

[0013] Figure 1 is the overall structural schematic diagram of the present utility model;

[0014] Figure 2 is the schematic diagram of the arrangement order of the magnetic steel on the rotor disc;

[0015] Figure 3 is the structural schematic diagram of the dovetail pressing plate;

[0016] Figure 4 is the structural schematic diagram of the annular magnetic conductive back yoke;

[0017] Figure 5 is the structural schematic diagram of the rotor disc;

[0018] Figure 6 is the structural schematic diagram of the assembly of the dovetail pressing plate and the magnetic steel;

[0019] Figure 7 is the structural schematic diagram of the rotating shaft;

[0020] Figure 8 is the structural schematic diagram of the installation of the double rotor discs.

[0021] Each reference numeral in the figure is: the first rotor disc 101; the second rotor disc 102; the magnetic steel 2; the dovetail pressing plate 3; the rotating shaft 4; the silicon steel disc 5. Specific embodiments

[0022] In the following description, a large number of specific details are given to provide a more thorough understanding of the present utility model. However, it is obvious to those skilled in the art that the present utility model can be implemented without one or more of these details. In other examples, in order to avoid confusion with the present utility model, some well-known technical features in the art are not described.

[0023] Refer to Figure 1 , the sector magnetic steel fixing disc of the present axial magnetic field motor includes a first rotor disc 101, a second rotor disc 102, a magnetic steel 2, a dovetail pressing plate 3, a rotating shaft 4, and a silicon steel disc 5. Among them, the magnetic steel 2 is in an isosceles trapezoidal shape by draft, both the upper and lower sides of the trapezoid are in an arc shape, the arc length of the arc is also determined by the pole arc, the arc sizes of the upper and lower sides correspond to the size of the stator, the arc sizes on both the inner and outer sides of the magnetic steel 2 are equal to the inner annular notch of the first rotor disc 101, a draft angle of 1° is made on both sides of the magnetic steel 2, the thickness of the magnetic steel 2 is equal to the depth of the annular groove of the first rotor disc 101, half of the thickness of the magnetic steel 2 is embedded in the annular groove of the first rotor disc 101, and the axial exposed height of the magnetic steel 2 is 5 mm. The arrangement order of the installation of the magnetic steel 2 on the first rotor disc 101 is as Figure 2 shown.

[0024] Refer to Figure 3, it is the dovetail pressure plate 3 of the permanent magnet 2. The dovetail pressure plate 3 is a special-shaped pressure plate, which can be regarded as an isosceles trapezoidal pressure plate in the shape of a long strip in appearance. It is connected to the outside of the first rotor disk 101 to form an inverted trapezoidal dovetail groove, and matches with the inside of the first rotor disk 101 to form a cylindrical hole. The arc sizes at both ends of the rectangular surface pressed against the permanent magnet 2 are equal to the inner and outer arcs of the permanent magnet 2. From the central cross-section of the dovetail pressure plate 3, the dovetail pressure plate 3 is in the shape of a regular rectangle and has a through hole in the center. There is a through groove from the upper end surface of the dovetail pressure plate 3 to the center of the circle. This groove is used to drive in a steel pin to make the cross-section of the dovetail pressure plate 3 in the shape of an inverted trapezoid, so as to play the role of pressing the permanent magnet 2.

[0025] Figure 4 It is an annular magnetic conductive back yoke, that is, the silicon steel disk 5, which is made by winding and is axially installed at the middle position between the permanent magnet 2 and the first rotor disk 101.

[0026] Figure 5 It is the first rotor disk 101, which is in the shape of a special-shaped claw. The inner side is an annular notch for installing the silicon steel disk 5 and the permanent magnet 2. About half of the permanent magnet 2 is embedded in the inverted notch. There are circular holes on the inner side and dovetail notches on the outer side, which are matched and connected with both ends of the dovetail pressure plate 3.

[0027] The installation sequence of the single-sided rotor is as follows: first, bond the silicon steel disk 5 and the first rotor disk 101 with structural adhesive, then put the dovetail pressure plate 3 into the mating slot hole, and then arrange the permanent magnets 2 with different magnetic poles staggered on the first rotor disk 101, as Figure 6 shown. Finally, insert a steel pin to deform the dovetail pressure plate 3 for pressing.

[0028] As Figure 7 、 Figure 8 shown in the structural schematic diagram of the rotor assembly, the first rotor disk 101 and the second rotor disk 102 are axially symmetric and are connected by a rotating shaft 4 to form a complete high-strength axial magnetic field surface-mounted double-rotor structure assembly. The first rotor disk 101 and the rotating shaft 4 are connected by a keyway and bolts.

[0029] The utility model is a surface-mounted permanent magnet rotor fixing disk for a high-strength axial magnetic field. The permanent magnet 2 has reliable fixing strength both axially and radially, solving the risk of the permanent magnet 2 falling off when the motor runs at high speed. The material selection of the first rotor disk 101 and the second rotor disk 102 is a high-strength magnetic conductive material. The structural design also effectively reduces the magnetic leakage loss, improves the overall performance of the motor, and improves the safety of the motor under load. The composition of this structure is simple, the assembly process sequence is concise, and the manufacturing cost of the rotor is effectively reduced.

[0030] As described above, although the present utility model has been shown and described with reference to specific preferred embodiments, it should not be construed as a limitation on the present utility model itself. Various changes may be made in its form and details without departing from the spirit and scope of the present utility model as defined by the appended claims.

Claims

1. A sector magnet fixing disk for an axial magnetic field motor, characterized in that, It includes a first rotor disk (101) and a second rotor disk (102) which are symmetrically installed face to face on a rotating shaft (4). The stator assembly is installed at a position spaced from the center on the first rotor disk (101). A silicon steel disk (5), a dovetail pressing plate (3), and a magnet (2) are installed at the inner opening of the annular groove on the first rotor disk (101). An annular groove is formed in the rotor disk. The rotor silicon steel disk (5) is installed in the annular groove of the first rotor disk (101). The dovetail pressing plates (3) are evenly distributed in a radial shape and cooperate with the first rotor disk (101). The magnets (2) are arranged in a trapezoidal cross shape and evenly distributed in the annular groove of the first rotor disk (101). The thickness of the magnet (2) is half the distance higher than that of the dovetail pressing plate (3). Steel pins with a diameter larger than the diameter of the through holes on the pressing plate are installed inward from the radial uniform distribution, causing the cross section of the dovetail pressing plate (3) to deform into an inverted trapezoid and press-fitting and fixing the magnet (2) at the axial position of the first rotor disk (101).

2. The sector magnet fixing disk of the axial magnetic field motor according to claim 1, wherein The magnet (2) is in a fan shape. The arc sizes on the inner and outer sides are equal to the inner annular groove opening of the first rotor disk (101). Draft angles at a fixed angle are made on both sides of the magnet (2). The thickness of the magnet (2) is equal to the depth of the annular groove of the first rotor disk (101).

3. The sector magnet fixing disk of the axial magnetic field motor according to claim 1, characterized in that, The silicon steel disk (5) is in an annular disk shape. The silicon steel disk (5) is made by winding an iron core. The inner and outer diameters of the inner and outer circles are the same as those of the annular groove of the first rotor disk (101). The thickness of the silicon steel disk is half the depth of the annular groove of the first rotor disk (101).

4. The sector magnet fixing disk of the axial magnetic field motor according to claim 1, characterized in that The first rotor disk (101) is in a disk claw shape. The inner and outer diameters of the annular groove are equal to those of the silicon steel disk (5) and the magnet (2). The round groove on the inner circle of the annular groove cooperates with the cylinder on the dovetail pressing plate (3). The inverted trapezoidal groove opening on the outer circle of the annular groove cooperates with the dovetail end of the dovetail pressing plate (3). Four counterbore holes and four threaded holes in the middle of the first rotor disk (101) are connected to the rotating shaft (4) and the second rotor disk (102) through bolts to form a rotor assembly.

5. The sector magnet fixing disk of the axial magnetic field motor according to claim 1, wherein , One section of the dovetail pressing plate (3) is in a cylindrical shape, and the other end is in a trapezoidal shape. The middle trapezoidal cross section gradually changes to connect the two ends. There are gaps with through holes and dividing holes in the middle of the dovetail pressing plate (3). The cylindrical section of the dovetail pressing plate (3) is connected to the round groove on the inner circle of the annular groove of the first rotor disk (101). The trapezoidal section of the dovetail pressing plate (3) cooperates with the trapezoidal groove on the outer edge of the annular groove of the rotor disk (1). The two side surfaces of the dovetail pressing plate (3) cooperate with the two side surfaces of the magnet (2). Steel pins are inserted into the middle hole of the dovetail pressing plate (3) radially, causing the dovetail pressing plate (3) to deform and press-fitting and fixing with the magnet (2).

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