Magnetic tile for high-speed motor rotor

Abstract

The utility model discloses a magnetic shoe for a high-speed motor rotor, which relates to the field of motors and comprises an upper cambered surface and a lower cambered surface, and longitudinal grooves are arranged on side surfaces of the upper cambered surface and the lower cambered surface. Compared with the prior art, the rotor is large in air gap, low in flux density at the air gap, low in power density, low in strength and incapable of bearing high rotating speed. According to the utility model, after the magnetic shoes and the rotor laminations are installed in a matched manner, plastic coating can be performed in gaps between the magnetic shoes and the rotor laminations, so that air gaps are eliminated, the magnetic shoes and the rotor can be firmly connected through plastic coating, and the rotor is high in overall strength and can operate under the condition of high rotating speed.

Description

Technical Field

[0001] This utility model relates to the field of motors, specifically to magnetic tiles for high-speed motor rotors with two or more magnets arranged circumferentially on the rotor. Background Technology

[0002] The air gap size of a brushless motor has a significant impact on its performance, mainly in the following aspects: Dynamic response performance: The smaller the air gap, the greater the electromagnetic force between the stator and rotor, resulting in better dynamic response performance, higher control precision, and higher reliability. Efficiency: The smaller the air gap, the less power is required to rotate the rotor, leading to higher motor efficiency. This is because a smaller air gap reduces power loss. Output torque: The smaller the air gap, the greater the output torque of the motor. Torque is determined by the electromagnetic force, which increases as the air gap decreases. Power factor: A smaller air gap reduces the excitation current, thus increasing the power factor.

[0003] Existing internal rotor brushless motors are divided into two structural types: those with embedded magnets and those with surface-mounted magnets. The embedded magnet structure has the magnets installed inside the rotor laminations, offering high stability and usability in high-speed environments (10,000-40,000 RPM). However, some magnetic fields are shielded by the iron core, resulting in a relatively large air gap and consequently, lower air gap magnetic flux density and power density. The surface-mounted magnet structure involves directly attaching the magnets to the rotor laminations with adhesive, followed by an external protective magnet ring. Again, the addition of the protective magnet ring results in a relatively large air gap, leading to lower air gap magnetic flux density and power density.

[0004] As disclosed in the patent CN108880031A, "Rotor Structure, Motor Rotor and Motor", the magnet is directly inserted into the iron core, but the air gap is large. Therefore, the high-speed performance of the brushless motor in this patent is poor and the energy loss is large. Utility Model Content

[0005] The purpose of this invention is to design the side of the magnet tile installed on the rotor of a brushless motor, especially a high-speed brushless motor, to install it with the rotor laminations, allowing for a large connection area after plastic coating and ensuring a firm and reliable installation. A further purpose of this invention is to ensure that the rotor laminations and magnet tile can rotate together as a single unit when the brushless motor rotor is rotating at high speed. Another purpose of this invention is to ensure a small electrical air gap, high magnetic density, high power density, and high motor efficiency.

[0006] This utility model achieves the above-mentioned technical objectives through the following technical means.

[0007] A magnetic tile for a high-speed motor rotor includes an upper arc surface and a lower arc surface. The sides of the upper arc surface and the lower arc surface are provided with longitudinal grooves. The upper arc surface is connected to an upper side segment, and the lower arc surface is connected to a lower side segment. A side wall groove is provided between the upper side segment and the lower side segment. The side wall grooves are symmetrically distributed on both sides of the magnetic tile for a high-speed motor rotor.

[0008] Furthermore, the extension line of the upper segment is tangent to the lower arc segment.

[0009] Furthermore, the upper wall of the side wall slot near the upper arc surface is the slotted upper wall, the lower wall near the lower arc surface is the slotted lower wall, and the connection part between the slotted upper wall and the slotted lower wall is the slotted side wall.

[0010] Furthermore, the width of the lower wall of the slot is 2 to 8 times the width of the upper wall of the slot.

[0011] Preferably, there is an angle α between the slotted sidewall and the upper section, and the degree of the angle α is in the range of 8° to 12°.

[0012] Furthermore, the lower arc segment has an outwardly convex circular arc structure.

[0013] Preferably, an upper arc surface platform is provided at the end face of the magnetic tile, which contacts the upper arc surface, and the height of the upper arc surface platform is lower than the end face of the magnetic tile.

[0014] Preferably, the groove is a lower arc segment, the lower arc surface is connected to the lower arc segment, the upper arc surface is connected to the upper side segment, the upper side segment is connected to one side of the lower arc segment, and the lower arc segment is connected to the other side of the lower arc surface. The lower arc segment is a concave chamfered arc structure.

[0015] Furthermore, the magnetic tile is fitted with the rotor lamination, and the rotor lamination has at least two magnetic tile mating points. The magnetic tile is installed between two adjacent magnetic tile mating points, and there is a plastic-coated part between the upper side section and the lower side arc section and the magnetic tile mating point.

[0016] Furthermore, the magnetic tile is fitted with the rotor lamination, and the rotor lamination has at least two magnetic tile mating points. The magnetic tile is installed between two adjacent magnetic tile mating points, and there is a plastic-coated part between the upper side section and the lower arc section and the magnetic tile mating point.

[0017] This invention has the following benefits:

[0018] Compared to the comparative technologies, the rotor has a larger air gap, lower magnetic flux density and power density at the air gap, and lower strength, making it unable to withstand high speeds. In this invention, after the magnetic tiles and rotor laminations are installed together, plastic wrapping can be applied to the gap between them, thereby eliminating the air gap. Furthermore, the plastic wrapping can firmly connect the magnetic tiles and the rotor, resulting in high overall rotor strength and the ability to operate at high speeds. Attached Figure Description

[0019] Figure 1 This is a three-dimensional structural diagram of one embodiment of the present invention.

[0020] Figure 2 for Figure 1 The front view of the embodiment.

[0021] Figure 3 This is a three-dimensional structural diagram of another embodiment of the present invention.

[0022] Figure 4 for Figure 3 The front view of the embodiment.

[0023] Figure 5 for Figure 1 Assembly diagram of the embodiment and rotor laminations.

[0024] Figure 6 for Figure 3 Assembly diagram of the embodiment and rotor laminations.

[0025] Figure 7 for Figure 2 A magnified view of part A in the middle.

[0026] In the figure, 1-upper arc surface, 11-upper arc surface platform, 2-lower arc surface, 3-upper side section, 4-side wall slot, 41-slotted upper wall, 42-slotted lower wall, 43-slotted side wall, 5-lower side arc section, 6-lower arc section, 7-rotor lamination, 71-magnetic tile mating area, 8-plastic coated part. Detailed Implementation

[0027] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited thereto.

[0028] Example 1:

[0029] In the rotor of a brushless motor, to achieve both high performance and high strength, magnetic tiles are arranged around the rotor's iron core. In this embodiment, as shown... Figure 1 and Figure 2 and Figure 5 as well as Figure 7 As shown, a high-speed motor rotor magnet is provided, wherein the magnet has an upper arc surface 1 and a lower arc surface 2 as the main mating parts with the rotor lamination 7. The lower arc surface 2 is the part where the magnet fits into the rotor lamination 7. The part of the rotor lamination 7 that contacts the lower arc surface 2 is an arc-shaped surface. The radius of the lower arc surface 2 is equal to the radius of the arc segment at the mating position of the rotor lamination, and it fits into the arc surface of the rotor lamination. A longitudinal groove is provided on the side wall between the upper arc surface 1 and the lower arc surface 2.

[0030] In this embodiment, the sidewall of the connecting portion between the upper arc surface 1 and the lower arc surface 2 can be considered to consist of three segments, namely, an upper side segment 3, a sidewall slot 4, and a lower arc segment 5, starting from the upper arc surface 1 and ending at the lower arc surface 2. The side of the upper arc surface 1 is connected to one side of the upper side segment 3. The other side of the upper side segment 3 is connected to one side of the sidewall slot 4, specifically, the other side of the upper side segment 3 is connected to one side of the slotted upper wall 41. The other side of the sidewall slot 4 is connected to one side of the lower arc segment 5, specifically, the slotted lower wall 42 is connected to one side of the lower arc segment 5. The other side of the lower arc segment 5 is connected to the side of the lower arc surface 2.

[0031] To further optimize magnet performance and enhance rotor strength and performance after installation and plastic coating of the magnetic tile and rotor laminations 7, this embodiment incorporates a sidewall slot 4 between the upper section 3 and the lower arc section 5. This sidewall slot 4 reduces the overall weight of the magnet, improving the dynamic response of the brushless motor. Furthermore, it increases the contact area and volume between the rotor laminations 7 and the plastic-coated magnetic tile, increasing coating strength and improving rotor stability at high speeds. Although the sidewall slot 4 slightly reduces the magnetic field performance of the magnetic tile, the loss is minimal, and the plastic coating eliminates the air gap between the magnetic tile and rotor laminations 7, increasing magnetic density and improving rotor efficiency. In this invention, the plastic coating is achieved by injection molding the air gap between the magnetic tile and rotor laminations 7. The injection molding material can be an injection molding compound or a single-component or multi-component solid-liquid adhesive.

[0032] The width of the slotted lower wall 42 is 2 to 8 times the width of the slotted upper wall 41. In this embodiment, if the width of the slotted upper wall 41 is b, then the width of the slotted lower wall 42 is 1.5b. Because the arc length of the magnetic tile increases continuously downwards from the upper arc surface 1, it is necessary to ensure that the depth of the slotted lower wall 42 is sufficient. Therefore, the width of the slotted lower wall 42 is 1 to 8 times the width of the slotted upper wall 41, and the specific value can be selected according to actual needs. At the same time, in order to ensure the coating effect, there is an included angle α between the slotted side wall 43 and the upper side section 3. The degree of the included angle α is in the range of 8° to 12°, and in this embodiment it is 9°, which can further improve the coating effect and allow the coating to fully fill the space between the rotor lamination 7 and the magnetic tile.

[0033] In addition, the lower arc segment 5 adopts an outward convex arc structure design, which makes the connection and transition between the slotted lower wall 42 and the lower arc surface 2 smoother, the stress distribution is uniform and it is not easy to break. It can be completely covered during plastic coating, and it is not easy to have plastic coating gaps, which would cause air gaps between the magnetic tile and the rotor lamination 7, resulting in low magnetic density at the air gap, which weakens the high-speed performance and efficiency of the rotor.

[0034] On the end face of the magnetic tile, near the upper arc surface 1, an upper arc surface platform 11 may be optionally provided. The upper arc surface platform 11 provides an additional fastening part for the plastic coating, improving the firmness and strength of the plastic coating. The height of the upper arc surface platform 11 is lower than the end face of the magnet, forming a step, which increases the contact area and volume of the plastic coating, ensuring the stability and reliability of the magnet during installation and use.

[0035] Example 2:

[0036] This embodiment uses a different magnetic tile structure compared to Embodiment 1.

[0037] like Figure 3 and Figure 4 as well as Figure 6 As shown, a high-speed motor rotor magnet has an upper arc surface 1 and a lower arc surface 2 as the main mating parts between the magnet and the rotor lamination 7. The lower arc surface 2 is the part where the magnet and the rotor lamination 7 are attached. The part of the rotor lamination 7 that contacts the lower arc surface 2 is an arc-shaped surface. The radius of the lower arc surface 2 is equal to the radius of the arc segment at the mating position of the rotor lamination, and it is attached to the arc surface of the rotor lamination.

[0038] In this embodiment, the sidewall of the connecting portion between the upper arc surface 1 and the lower arc surface 2 can be considered as consisting of two segments: an upper side segment 3 and a lower arc segment 6, extending from the upper arc surface 1 to the lower arc surface 2. One side of the upper arc surface 1 connects to one side of the upper side segment 3. The other side of the upper side segment 3 connects to one side of the lower arc segment 6. The other side of the lower arc segment 6 connects to the side of the lower arc surface 2.

[0039] To further optimize magnet performance, this embodiment enhances rotor strength and performance after the magnetic tiles are installed and plastic-coated with the rotor laminations 7. The lower arc segment 6 features an inwardly concave chamfer. This lower arc segment 6 reduces the overall weight of the magnet, improving the dynamic response of the brushless motor. Furthermore, it increases the contact area and volume between the rotor laminations 7 and the plastic-coated magnetic tiles, increasing the plastic coating strength and improving the stability of the motor rotor during high-speed rotation.

[0040] Although the lower arc segment 6 on the sidewall of the magnetic tile causes some loss to the magnetic field performance, the loss is small. Furthermore, the plastic coating eliminates the air gap between the magnetic tile and the rotor laminations 7, increasing magnetic density and improving rotor efficiency. Compared to the sidewall slot 4 in Embodiment 1, the lower arc segment 6 in this embodiment disrupts less of the magnetic tile structure, resulting in a more rational structure, a more reasonable magnetic field distribution, and a more uniform magnetic field strength. After assembly with the rotor laminations 7, the plastic coating effect is better, resulting in higher magnetic density and higher efficiency.

[0041] On the end face of the magnetic tile, near the upper arc surface 1, an upper arc surface platform 11 may be optionally provided. The upper arc surface platform 11 provides an additional fastening part for the plastic coating, improving the firmness and strength of the plastic coating. The height of the upper arc surface platform 11 is lower than the end face of the magnet, forming a step, which increases the contact area and volume of the plastic coating, ensuring the stability and reliability of the magnet during installation and use.

[0042] Example 3:

[0043] This embodiment, based on Embodiment 1, specifically describes how the magnetic tiles in Embodiment 1 cooperate with the rotor laminations 7.

[0044] In the rotor of a brushless motor, to achieve both high performance and high strength, magnetic tiles are arranged around the rotor's iron core. In this embodiment, as shown... Figure 1 and Figure 2 and Figure 5 as well as Figure 7 As shown, a high-speed motor rotor magnet has an upper arc surface 1 and a lower arc surface 2 as the main mating parts between the magnet and the rotor lamination 7. The lower arc surface 2 is the part where the magnet and the rotor lamination 7 are attached. The part of the rotor lamination 7 that contacts the lower arc surface 2 is an arc-shaped surface. The radius of the lower arc surface 2 is equal to the radius of the arc segment at the mating position of the rotor lamination, and it is attached to the arc surface of the rotor lamination.

[0045] In this embodiment, the sidewall of the connection between the upper arc surface 1 and the lower arc surface 2 can be considered to consist of three segments, namely, an upper side segment 3, a sidewall slot 4, and a lower arc segment 5, starting from the upper arc surface 1 and ending at the lower arc surface 2. The side of the upper arc surface 1 is connected to one side of the upper side segment 3. The other side of the upper side segment 3 is connected to one side of the sidewall slot 4, specifically, the other side of the upper side segment 3 is connected to one side of the slotted upper wall 41. The other side of the sidewall slot 4 is connected to one side of the lower arc segment 5, specifically, the slotted lower wall 42 is connected to one side of the lower arc segment 5. The other side of the lower arc segment 5 is connected to the side of the lower arc surface.

[0046] To further optimize magnet performance and enhance rotor strength and performance after the magnetic tile and rotor laminations 7 are installed and fixed with plastic coating, this embodiment incorporates a sidewall slot 4 between the upper section 3 and the lower arc section 5. This sidewall slot 4 reduces the overall weight of the magnet, improving the dynamic response of the brushless motor. Furthermore, it increases the contact area and volume between the rotor laminations 7 and the plastic-coated magnetic tile, increasing the coating strength and improving the stability of the motor rotor at high speeds. Although the sidewall slot 4 slightly reduces the magnetic field performance of the magnetic tile, the loss is minimal, and the plastic coating eliminates the air gap between the magnetic tile and the rotor laminations 7, increasing magnetic density and improving rotor efficiency.

[0047] The width of the slotted lower wall 42 is 2 to 8 times the width of the slotted upper wall 41. In this embodiment, if the width of the slotted upper wall 41 is b, then the width of the slotted lower wall 42 is 1.5b. Because the arc length of the magnetic tile increases continuously downwards from the upper arc surface 1, it is necessary to ensure that the depth of the slotted lower wall 42 is sufficient. Therefore, the width of the slotted lower wall 42 is 1 to 8 times the width of the slotted upper wall 41, and the specific value can be selected according to actual needs. At the same time, in order to ensure the coating effect, there is an included angle α between the slotted side wall 43 and the upper side section 3. The degree of the included angle α is in the range of 8° to 12°, and in this embodiment it is 9°, which can further improve the coating effect and allow the coating to fully fill the space between the rotor lamination 7 and the magnetic tile.

[0048] In addition, the lower arc segment 5 adopts an outward convex arc structure design, which makes the connection and transition between the slotted lower wall 42 and the lower arc surface 2 smoother, the stress distribution is uniform and it is not easy to break. It can be completely covered during plastic coating, and it is not easy to have plastic coating gaps, which would cause air gaps between the magnetic tile and the rotor lamination 7, resulting in low magnetic density at the air gap, which weakens the high-speed performance and efficiency of the rotor.

[0049] On the end face of the magnetic tile, near the upper arc surface 1, an upper arc surface platform 11 may be optionally provided. The upper arc surface platform 11 provides an additional fastening part for the plastic coating, improving the firmness and strength of the plastic coating. The height of the upper arc surface platform 11 is lower than the end face of the magnet, forming a step, which increases the contact area and volume of the plastic coating, ensuring the stability and reliability of the magnet during installation and use.

[0050] The magnetic tile mates with the rotor lamination 7, and at least two magnetic tile mating points 71 are provided on the rotor lamination 7. The magnetic tile mating points 71 have an inverted triangular structure. The magnetic tile is installed between two adjacent magnetic tile mating points 71. The arc length between the roots of two adjacent magnetic tile mating points 71 is slightly greater than the arc length of the lower arc surface 2. The arc length between the tops of two adjacent magnetic tile mating points 71 is slightly greater than the arc length of the upper arc surface 1. There is a gap between the upper side segment 3 and the lower side arc segment 5 and the magnetic tile mating point 71, and the gap is the plastic-coated part 8.

[0051] Example 4:

[0052] This embodiment, based on embodiment two, specifically describes how the magnetic tiles in embodiment two cooperate with the rotor laminations 7.

[0053] like Figure 3 and Figure 4 as well as Figure 6 As shown, a high-speed motor rotor magnet has an upper arc surface 1 and a lower arc surface 2 as the main mating parts between the magnet and the rotor lamination 7. The lower arc surface 2 is the part where the magnet and the rotor lamination 7 are attached. The part of the rotor lamination 7 that contacts the lower arc surface 2 is an arc-shaped surface. The radius of the lower arc surface 2 is equal to the radius of the arc segment at the mating position of the rotor lamination, and it is attached to the arc surface of the rotor lamination.

[0054] In this embodiment, the sidewall of the connecting portion between the upper arc surface 1 and the lower arc surface 2 can be considered as consisting of two segments: an upper side segment 3 and a lower arc segment 6, extending from the upper arc surface 1 to the lower arc surface 2. One side of the upper arc surface 1 connects to one side of the upper side segment 3. The other side of the upper side segment 3 connects to one side of the lower arc segment 6. The other side of the lower arc segment 6 connects to the side of the lower arc surface 2.

[0055] To further optimize magnet performance, this embodiment enhances rotor strength and performance after the magnetic tiles are installed and plastic-coated with the rotor laminations 7. The lower arc segment 6 features an inwardly concave chamfer. This lower arc segment 6 reduces the overall weight of the magnet, improving the dynamic response of the brushless motor. Furthermore, it increases the contact area and volume between the rotor laminations 7 and the plastic-coated magnetic tiles, increasing the plastic coating strength and improving the stability of the motor rotor during high-speed rotation.

[0056] Although the lower arc segment 6 on the sidewall of the magnetic tile causes some loss to the magnetic field performance, the loss is small. Furthermore, the plastic coating eliminates the air gap between the magnetic tile and the rotor laminations 7, increasing magnetic density and improving rotor efficiency. Compared to the sidewall slot 4 in Embodiment 1, the lower arc segment 6 in this embodiment disrupts less of the magnetic tile structure, resulting in a more rational structure, a more reasonable magnetic field distribution, and a more uniform magnetic field strength. After assembly with the rotor laminations 7, the plastic coating effect is better, resulting in higher magnetic density and higher efficiency.

[0057] On the end face of the magnetic tile, near the upper arc surface 1, an upper arc surface platform 11 may be optionally provided. The upper arc surface platform 11 provides an additional fastening part for the plastic coating, improving the firmness and strength of the plastic coating. The height of the upper arc surface platform 11 is lower than the end face of the magnet, forming a step, which increases the contact area and volume of the plastic coating, ensuring the stability and reliability of the magnet during installation and use.

[0058] The magnetic tile mates with the rotor lamination 7, and at least two magnetic tile mating points 71 are provided on the rotor lamination 7. The magnetic tile mating points 71 have an inverted triangular structure. The magnetic tile is installed between two adjacent magnetic tile mating points 71. The arc length between the roots of two adjacent magnetic tile mating points 71 is slightly greater than the arc length of the lower arc surface 2. The arc length between the tops of two adjacent magnetic tile mating points 71 is slightly greater than the arc length of the upper arc surface 1. There is a gap between the upper side segment 3 and the lower side arc segment 5 and the magnetic tile mating point 71, and the gap is the plastic-coated part 8.

Claims

1. A magnetic tile for a high speed motor rotor, characterized by, It includes an upper arc surface (1) and a lower arc surface (2). The upper arc surface (1) and the lower arc surface (2) are provided with longitudinal grooves on their sides. The upper arc surface (1) is connected to the upper side section (3). The lower arc surface (2) is connected to the lower side arc section (5). A side wall slot (4) is provided between the upper side section (3) and the lower side arc section (5). The side wall slot (4) is symmetrically distributed on both sides of the high-speed motor rotor magnet.

2. The high speed motor rotor tile of claim 1, wherein, The extension of the upper segment (3) is tangent to the lower arc segment (5).

3. The high speed motor rotor tile of claim 2, wherein, The upper wall of the side wall groove (4) near the upper arc surface (1) is the grooved upper wall (41), and the lower wall near the lower arc surface (2) is the grooved lower wall (42). The connection between the grooved upper wall (41) and the grooved lower wall (42) is the grooved side wall (43).

4. The high speed motor rotor tile of claim 3, wherein, The width of the slotted lower wall (42) is 1.2 to 1.8 times the width of the slotted upper wall (41).

5. The high speed motor rotor tile of claim 3, wherein, There is an angle α between the slotted sidewall (43) and the upper side section (3), and the degree of the angle α is in the range of 8° to 12°.

6. The high speed electric motor rotor tile of claim 2 or 3 or 4 or 5, wherein, The lower arc segment (5) is a convex circular arc structure.

7. The high speed electric motor rotor tile of claim 1, wherein, At the end face of the magnetic tile, an upper arc surface platform (11) is provided in contact with the upper arc surface (1), and the height of the upper arc surface platform (11) is lower than the end face of the magnetic tile.

8. The high speed motor rotor tile of claim 1, wherein, The groove is a lower arc segment (6), the lower arc surface (2) is connected to the lower arc segment (6), the upper arc surface (1) is connected to the upper side segment (3), the upper side segment (3) is connected to one side of the lower arc segment (6), the lower arc segment (6) is connected to the other side of the lower arc surface (2), and the lower arc segment (6) is a concave chamfered arc structure.

9. The high speed electric motor rotor tile of claim 2 or 3 or 4 or 5, wherein, The magnetic tile is fitted with the rotor lamination (7). The rotor lamination (7) has at least two magnetic tile mating points (71). The magnetic tile is installed between two adjacent magnetic tile mating points (71). There is a plastic-coated part (8) between the upper side section (3) and the lower side arc section (5) and the magnetic tile mating point (71).

10. The high speed motor rotor tile of claim 7 or 8, wherein, The magnetic tile is fitted with the rotor lamination (7). The rotor lamination (7) has at least two magnetic tile mating points (71). The magnetic tile is installed between two adjacent magnetic tile mating points (71). There is a plastic-coated part (8) between the upper side section (3) and the lower arc section (6) and the magnetic tile mating point (71).

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