Permanent magnet rotor assembly with magnetic ring and motor

Abstract

The utility model discloses a permanent magnet rotor assembly with magnetic ring and motor, including a plurality of permanent magnet, rotor core and magnetic ring, and the plastic package body is injected molding into a whole with a plurality of permanent magnet and rotor core, and the plastic package body includes upper end plate and lower end plate, and the upper end plate and lower end plate are connected into a whole through the connecting column, and the upper end plate is close to the edge position and projects a annular boss, and the annular boss's inboard side projects the equidistant distribution of a plurality of arc line inner baffle axially, and the arc line inner baffle's top end projects the briquet outward, and the magnetic ring's bottom end surface supports on the annular boss and is covered outside a plurality of arc line inner baffle, and the briquet is pressed in the top end surface of magnetic ring and makes magnetic ring unable to move axially, and the inner side surface of magnetic ring is excavated with the clamping slot, and the middle part of briquet projects the clamping block downward, and the clamping block is nested in the clamping slot, and the magnetic ring is integrally injection molded with permanent magnet and rotor core, and the positioning effect is good, and the concentricity is high.

Description

Technical Field

[0001] This utility model relates to a permanent magnet rotor assembly with a magnetic ring and a motor. Background Technology

[0002] The rotor assembly of a traditional brushless DC motor typically includes a rotor core, permanent magnets, a magnetic ring support, and a magnetic ring. The permanent magnets are mounted on the rotor core, the magnetic ring support is connected to the rotor core, and the magnetic ring is nested in the magnetic ring support.

[0003] BLDC motors can be designed with Hall effect sensing or without Hall effect sensors. Hall effect sensing motors use Hall effect sensors to detect the position and speed of the magnetic ring on the rotor. When the magnetic ring on the rotor passes the Hall effect sensor, the sensor generates a corresponding electrical signal.

[0004] Currently, the magnetic rings on permanent magnet rotor assemblies with magnetic rings are assembled onto injection-molded rotors by applying AB glue. This has the following problems: 1) AB glue dries easily, and after applying a few, it needs to be remixed before the next application, which is difficult to operate and inefficient; 2) The magnetic rings are glued to the rotor, resulting in poor concentricity. Summary of the Invention

[0005] This utility model provides a permanent magnet rotor assembly and motor with a magnetic ring, which solves the technical problems of existing permanent magnet rotor assemblies with magnetic rings being assembled on injection-molded rotors by applying AB glue for bonding and fixing, which is difficult to operate, inefficient and has poor concentricity.

[0006] The technical solution of this utility model is implemented as follows:

[0007] A permanent magnet rotor assembly with a magnetic ring includes several permanent magnets, a rotor core, and a magnetic ring. The rotor core includes an annular ring with a central shaft hole and several magnetically conductive blocks protruding from the outside of the annular ring. Through holes are formed on the magnetically conductive blocks, and radial grooves are formed between adjacent magnetically conductive blocks. Several permanent magnets are embedded in the radial grooves. A molding compound molds the several permanent magnets and the rotor core into a single unit. The molding compound includes an upper end plate and a lower end plate, which are connected as a single unit by connecting posts. The assembly is characterized by:

[0008] A ring-shaped boss protrudes from the upper end plate near the edge. Several circumferentially spaced arc-shaped inner baffles protrude axially from the inner side of the ring-shaped boss. A pressure block protrudes outward from the top of the arc-shaped inner baffles. The bottom end face of the magnetic ring is supported on the ring-shaped boss and fits over the arc-shaped inner baffles. The pressure block presses on the top face of the magnetic ring to prevent the magnetic ring from moving axially. A slot is carved on the inner side of the magnetic ring. A locking block protrudes downward from the middle of the pressure block and is nested in the slot.

[0009] Preferably, a number of positioning protrusions are circumferentially spaced on the inner side of the magnetic ring, and a positioning post is provided on the top surface of the upper end plate between two adjacent arc inner baffles. A second slot is provided on the top of the positioning post, and an annular boss protrudes axially from the second slot. The positioning protrusions are nested in the second slot.

[0010] Preferably, there are three positioning protrusions, which are not evenly distributed.

[0011] Preferably, there are six inner baffles along the arc.

[0012] Preferably, the axial length of the permanent magnets is greater than the axial length of the rotor core. Therefore, the two ends of the permanent magnets protrude from the end face of the rotor core, and the upper end plate and the lower end plate cover the end face of the rotor core and the ends of the permanent magnets, respectively.

[0013] Preferably, the magnetic ring is made by injection molding a layer of plastic onto the outside of a toroidal ferrite, and the toroidal ferrite has 5 N magnetic poles and 5 S magnetic poles.

[0014] An electric motor includes a stator assembly, a housing assembly, and a permanent magnet rotor assembly, characterized in that: the permanent magnet rotor assembly adopts the aforementioned permanent magnet rotor assembly with a magnetic ring.

[0015] Compared with the prior art, this utility model has the following advantages:

[0016] 1. This utility model features an annular boss protruding near the edge of the upper plate. Several circumferentially spaced arc-shaped inner baffles protrude axially from the inner side of the annular boss. A pressure block protrudes outward from the top of each arc-shaped inner baffle. The bottom surface of the magnetic ring rests on the annular boss and is fitted over the arc-shaped inner baffles. The pressure block presses against the top surface of the magnetic ring, preventing axial movement. A groove is carved into the inner surface of the magnetic ring, and a locking block protrudes downward from the center of the pressure block, nesting within the groove. The magnetic ring, permanent magnet, and rotor core are integrally injection molded, resulting in good positioning and high concentricity, solving the problems of low efficiency and poor concentricity leading to edge rubbing when using AB glue to attach magnetic ring components.

[0017] 2. Other advantages of this utility model are described in detail in the embodiments section. Attached Figure Description

[0018] Figure 1 This is a perspective view of Embodiment 1 of the present utility model;

[0019] Figure 2 This is the first exploded view of Embodiment 1 of this utility model;

[0020] Figure 3 This is the second exploded view of Embodiment 1 of this utility model;

[0021] Figure 4This is the third exploded view of Embodiment 1 of this utility model;

[0022] Figure 5 This is a top view of Embodiment 1 of the present utility model;

[0023] Figure 6 for Figure 5 AA section view;

[0024] Figure 7 yes Figure 6 BB cross-sectional view;

[0025] Figure 8 This is a cross-sectional view of the structure of Embodiment 2 of this utility model. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0027] Example 1:

[0028] like Figures 1 to 7 As shown, this embodiment provides a permanent magnet rotor assembly with a magnetic ring, including a plurality of permanent magnets 1, a rotor core 2, and a magnetic ring 4. The rotor core 2 includes an annular ring 22 with a central shaft hole 21 and a plurality of magnetically conductive blocks 23 protruding from the outside of the annular ring 22. Through holes 27 are formed on the magnetically conductive blocks 23, and radial grooves 24 are formed between adjacent magnetically conductive blocks 23. The plurality of permanent magnets 1 are embedded in the radial grooves 24. A molding compound 3 injection molds the plurality of permanent magnets 1 and the rotor core 2 into a whole. The molding compound 3 includes an upper end plate 35 and a lower end plate 36, which are connected into a whole by connecting posts 37. The characteristic of this embodiment is that:

[0029] A ring-shaped boss 31 protrudes from the upper end plate 35 near its edge. Several circumferentially spaced arc-shaped inner baffles 32 protrude axially from the inner side of the ring-shaped boss 31. A pressure block 33 protrudes outward from the top of each arc-shaped inner baffle 32. The bottom surface of the magnetic ring 4 rests on the ring-shaped boss 31 and is fitted over the arc-shaped inner baffles 32. The pressure block 33 presses against the top surface of the magnetic ring 4, preventing axial movement. A groove 42 is carved into the inner surface 41 of the magnetic ring 4. A retaining block 331 protrudes downward from the center of the pressure block 33 and is nested within the groove 42. The magnetic ring 4, permanent magnet 1, and rotor core 2 are integrally injection molded, resulting in good positioning and high concentricity, thus solving the problems of low efficiency and edge rubbing caused by poor concentricity when employees use AB glue to attach magnetic ring components. A slot 42 is cut into the inner side 41 of the magnetic ring 4, and a block 331 protrudes downward in the middle of the pressure block 33. The block 331 is nested in the slot 42 to increase the bonding force between the parts.

[0030] Preferably, a number of positioning protrusions 43 are circumferentially protruding on the inner side 41 of the magnetic ring 4, and a positioning post 38 is provided on the top surface of the upper end plate 35 between two adjacent arc inner baffles 32. A second slot 381 is provided on the top of the positioning post 38, and an annular boss 31 protrudes axially from the second slot 381. The positioning protrusions 43 are nested in the second slot 381, which ensures accurate positioning and is easy to manufacture.

[0031] Preferably, there are three positioning protrusions 43, which are unevenly distributed. The three unevenly distributed protrusions are at a fixed angle to the N pole, which ensures the relative position with the permanent magnet 1 during mold injection, ensuring that the Hall sensor can identify the Hall angle, and at the same time achieving a foolproof function.

[0032] Preferably, there are 6 inner baffles 32 of the arc.

[0033] Preferably, the axial length of the permanent magnets 1 is greater than the axial length of the rotor core 2. Therefore, the two ends of the permanent magnets 1 protrude from the end face of the rotor core 2 to improve the magnetic coupling force. The upper end plate 35 and the lower end plate 36 respectively cover the end face of the rotor core 2 and the ends of the permanent magnets 1.

[0034] The magnetic ring 4 is integrated with other components by injection molding, protruding above the end face of the rotor core 2, and is positioned as close as possible to the Hall plate assembly for easy identification by the Hall sensor.

[0035] Preferably, the magnetic ring 4 is made by injection molding a layer of plastic onto the outside of a ring-shaped ferrite, and the ring-shaped ferrite is provided with 5 N magnetic poles and 5 S magnetic poles, which is simple and convenient to manufacture.

[0036] Example 2:

[0037] like Figure 8As shown, this embodiment provides a motor, including a stator assembly 100, a housing assembly 200, and a permanent magnet rotor assembly 300. The permanent magnet rotor assembly 300 is characterized by employing the permanent magnet rotor assembly with a magnetic ring as described in Embodiment 1. The magnetic ring 4 of the permanent magnet rotor assembly 300 is integrally injection molded with the permanent magnet 1 and the rotor core 2, resulting in good positioning and high concentricity. This solves the problems of low efficiency and poor concentricity leading to edge rubbing when employees use AB glue to attach the magnetic ring assembly.

[0038] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A permanent magnet rotor assembly with a magnetic ring, comprising a plurality of permanent magnets (1), a rotor core (2), and a magnetic ring (4), wherein the rotor core (2) comprises an annular ring (22) having a central shaft hole (21) and a plurality of magnetically conductive blocks (23) protruding from the outside of the annular ring (22), wherein through holes (27) are formed on the magnetically conductive blocks (23), and radial grooves (24) are formed between adjacent magnetically conductive blocks (23), wherein the plurality of permanent magnets (1) are embedded in the radial grooves (24), and a molding compound (3) injection molds the plurality of permanent magnets (1) and the rotor core (2) into a whole, wherein the molding compound (3) comprises an upper end plate (35) and a lower end plate (36), the upper end plate (35) and the lower end plate (36) being connected into a whole by a connecting post (37), characterized in that: An annular boss (31) protrudes from the upper end plate (35) near the edge. Several arc-shaped inner baffles (32) are axially protruding from the inner side of the annular boss (31) and spaced outward from the top of the arc-shaped inner baffles (32). A pressure block (33) protrudes outward from the top of the arc-shaped inner baffles (32). The bottom surface of the magnetic ring (4) is supported on the annular boss (31) and fits on the outside of the several arc-shaped inner baffles (32). The pressure block (33) presses on the top surface of the magnetic ring (4) so ​​that the magnetic ring (4) cannot move axially. A slot (42) is carved on the inner side (41) of the magnetic ring (4). A locking block (331) protrudes downward from the middle of the pressure block (33) and is nested in the slot (42).

2. The permanent magnet rotor assembly with a magnetic ring according to claim 1, characterized in that: Several positioning protrusions (43) are circumferentially protruding on the inner side (41) of the magnetic ring (4). A positioning post (38) is provided on the top surface of the upper end plate (35) between two adjacent arc inner baffles (32). A second slot (381) is provided on the top of the positioning post (38). An annular boss (31) protrudes axially from the second slot (381). The positioning protrusions (43) are nested inside the second slot (381).

3. A permanent magnet rotor assembly with a magnetic ring according to claim 2, characterized in that: There are three positioning bumps (43), and they are not evenly distributed.

4. A permanent magnet rotor assembly with a magnetic ring according to claim 1, 2, or 3, characterized in that: There are 6 curved inner baffles (32).

5. A permanent magnet rotor assembly with a magnetic ring according to claim 4, characterized in that: The axial length of several permanent magnets (1) is greater than the axial length of the rotor core (2). Therefore, the two ends of the permanent magnets (1) protrude from the end face of the rotor core (2). The upper end plate (35) and the lower end plate (36) cover the end face of the rotor core (2) and the ends of several permanent magnets (1), respectively.

6. A permanent magnet rotor assembly with a magnetic ring according to claim 5, characterized in that: The magnetic ring (4) is made by injection molding a layer of plastic on the outside of the annular ferrite, and the annular ferrite has 5 N magnetic poles and 5 S magnetic poles.

7. An electric motor comprising a stator assembly (100), a housing assembly (200), and a permanent magnet rotor assembly (300), characterized in that: The permanent magnet rotor assembly (300) adopts the permanent magnet rotor assembly with magnetic ring as described in any one of claims 1 to 6.

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