High-strength brushless motor rotor structure

Abstract

The utility model relates to the technical field of motor rotors, in particular to a high-strength brushless motor rotor structure, which comprises a rotating shaft, a shaft sleeve, a plurality of rotor cores, magnetic shoes and a rotor injection molding body, the shaft sleeve is coaxially arranged outside the rotating shaft, a tooth part and a limiting space are formed on the surface of the shaft sleeve, and the plurality of rotor cores are stacked along the axial direction of the shaft sleeve. Tooth grooves matched with the tooth parts are formed in the surface of the rotor iron core, and the width sizes of the tooth parts are gradually increased from inside to outside in the radial direction of the shaft sleeve. Compared with a traditional method, according to the technical scheme, the rotor iron core is effectively connected and positioned through the shaft sleeve, and the rotor injection molding body is tightly combined with all parts, so that the overall structural strength of the rotor is remarkably improved compared with that of a traditional design, the parts are connected more stably when the rotor bears external force such as torque and centrifugal force, and the service life of the rotor is prolonged. The motor is not easy to loosen, deform or damage, and the reliability and the service life of the motor are effectively improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to motor rotor technical field, concretely relates to a high strength brushless motor rotor structure. BACKGROUND

[0002] The rotor of a brushless motor is one of its core components, usually made of multiple permanent magnets, which are fixed on a circular frame that can rotate freely inside the motor. The design and manufacture of the rotor are crucial to the performance of the entire motor.

[0003] The patent document with patent announcement number CN206180720U discloses a kind of assembled EPS brushless motor rotor structure, including rotating shaft, magnetic separation shaft sleeve, magnetic steel sheath, rotor core and magnetic steel, the scheme provides a kind of assembled EPS brushless motor rotor structure, this structure uses the positioning groove of magnetic separation shaft sleeve and magnetic steel sheath is equipped with positioning protrusion fixed magnetic steel and assembled iron core.Cut off EPS brushless motor rotor magnetic steel leakage path, force rotor magnetic steel magnetic flux to pass through air gap and winding turn chain, reduce the motor leakage, increase motor main magnetic flux to improve motor power density and efficiency.

[0004] The connection between the rotor cores and the connection between the rotor cores and the magnetic separation shaft sleeve in the above-mentioned rotor structure are not tight enough, which greatly reduces the structural reliability and cannot meet the use requirements of high-strength torque. SUMMARY

[0005] The utility model aims at at least one of the technical problems in the related art to some extent. To this end, the utility model aims to provide a high-strength brushless motor rotor structure to improve the strength of the rotor structure and reduce the cost.

[0006] The purpose of the utility model can be achieved by the following technical solutions:

[0007] A high-strength brushless motor rotor structure includes a rotating shaft, a shaft sleeve, a rotor core, a magnetic tile, and a rotor injection body. The shaft sleeve is coaxially installed outside the rotating shaft. The surface of the shaft sleeve is formed with a tooth portion and a limiting space. Multiple rotor cores are stacked along the axial direction of the shaft sleeve. The surface of the rotor core is formed with a tooth groove matching the tooth portion. The width of the tooth portion gradually increases from the inside to the outside along the radial direction of the shaft sleeve.

[0008] The magnetic tile is placed between adjacent rotor cores. The size of the magnetic tile matches the size of the limiting space. The rotor injection body is injection molded on the surface of the assembly composed of the rotating shaft, the shaft sleeve, the rotor core, and the magnetic tile.

[0009] In some embodiments of the utility model, the shaft sleeve includes hollow pipe and the limiting sleeve of installing in the hollow pipe outside, the middle part of hollow pipe is equipped with the shaft hole with the size of pivot matching and is opened to the limiting space and the tooth portion of the outer surface of limiting sleeve is formed with a plurality of, and the tooth portion and limiting space staggeredly set.

[0010] In some embodiments of the utility model, the limiting sleeve has the injection molding gap that is opened along its axial direction when looking from above, the position of injection molding gap coincides with the middle position of limiting space, and the radial dimension of injection molding gap to the shaft center of limiting sleeve is less than the radial dimension of limiting space to the shaft center of limiting sleeve.

[0011] In some embodiments of the utility model, the end angle of tooth portion, limiting space and injection molding gap is all done with round angle processing.

[0012] In some embodiments of the utility model, the rotor core is triangular structure, and the rotor core has the injection molding through hole that is opened along the axial direction of shaft sleeve when looking from above.

[0013] In some embodiments of the utility model, the inside of rotor injection molding body is formed with the injection molding connecting column that is matched with its size at the injection molding through hole.

[0014] In some embodiments of the utility model, the shaft sleeve is split type structure or integral type structure.

[0015] The utility model discloses beneficial effect:

[0016] Compared with traditional method, the technical scheme is through the effective connection and positioning of shaft sleeve to rotor core and the close combination of rotor injection molding body and each component, so that the overall structural strength of rotor is significantly improved compared with traditional design, when the external force such as torque and centrifugal force is borne, the connection between each component is more stable, and it is not easy to loosen, deform or damage, effectively improve the reliability and service life of motor. ACCURACY OF DRAWINGS

[0017] The utility model will be further described below in combination with the drawings.

[0018] Figure 1 It is the perspective view of the utility model;

[0019] Figure 2 It is the explosion view of the utility model;

[0020] Figure 3 It is the top view of shaft sleeve, rotor core and magnetic shoe in the utility model;

[0021] Figure 4 It is the perspective view of the shaft sleeve in the utility model;

[0022] Figure 5 This is a top view of the bushing of this utility model;

[0023] Figure 6 This is a top view of the rotor core in this utility model;

[0024] Figure 7 This is a perspective view of the rotor injection molded body in this utility model;

[0025] Figure 8 This is a three-dimensional view of the integrated structural bushing in this utility model.

[0026] In the figure: 1. Shaft; 2. Bushing; 21. Hollow tube; 22. Limiting sleeve; 23. Shaft hole; 24. Tooth; 25. Limiting space; 26. Injection notch; 3. Rotor core; 31. Tooth groove; 32. Injection through hole; 4. Magnet; 5. Rotor injection body; 51. Injection connecting column. Detailed Implementation

[0027] The technical solutions of this utility model will be clearly and completely described below with reference to the embodiments of this utility model. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of this utility model.

[0028] like Figure 1 , Figure 2 As shown, a high-strength brushless motor rotor structure includes a rotating shaft 1, a bushing 2, a rotor core 3, a magnet 4, and a rotor injection-molded body 5. The bushing 2 is coaxially mounted outside the rotating shaft 1. The surface of the bushing 2 has teeth 24 and limiting spaces 25. Multiple rotor cores 3 are stacked along the axial direction of the bushing 2, and the surface of the rotor core 3 has grooves 31 that match the teeth 24. Figure 5 As shown, the width of the tooth 24 gradually increases from the inside to the outside along the radial direction of the bushing 2;

[0029] Magnets 4 are placed between adjacent rotor cores 3. The size of the magnets 4 matches the size of the limiting space 25. The rotor injection body 5 is injection molded on the surface of the assembly consisting of the rotating shaft 1, the bushing 2, the rotor core 3 and the magnets 4.

[0030] In the assembly of the brushless motor rotor structure, first, the shaft sleeve 2 is sleeved on the rotating shaft 1 to provide a stable basis for subsequent component installation, then a plurality of rotor cores 3 are placed in sequence along the axial direction of the shaft sleeve 2, the tooth slots 31 of the rotor cores 3 are aligned with the tooth portions 24 of the limiting sleeve 22 and are slowly inserted, due to the special width gradient design of the tooth portions 24, as the rotor cores 3 are installed, the connection between the rotor cores 3 and the shaft sleeve 2 will be more and more close, until all the rotor cores 3 are installed in place, at this time, the space between adjacent rotor cores 3 is used to place the magnetic tiles 4; then the magnetic tiles 4 are placed one by one in the limiting spaces 25 between adjacent rotor cores 3, to ensure that the magnetic tiles 4 and the limiting spaces 25 are matched in size and closely fit, to provide a stable magnetic field for the motor; finally, after the installation of the above components is completed, the entire assembly is placed in an injection mold, and after the injection material cools and solidifies, the rotor injection body 5 is formed, so that the components are firmly connected as a whole.

[0031] In the scheme, the rotating shaft 1 serves as a core rotating component to provide support and a rotating shaft for the entire rotor, the shaft sleeve 2 is coaxially and closely installed outside the rotating shaft 1, and its unique structure design plays a key role in rotor assembly and performance optimization, a plurality of rotor cores 3 are orderly stacked along the axial direction of the shaft sleeve 2, the space between adjacent rotor cores 3 is reserved for placing the magnetic tiles 4, and the rotor injection body 5 is finally injection molded on the surface of the entire assembly to fix and protect the internal components, thereby ensuring the structural stability of the rotor during high-speed operation.

[0032] In some embodiments of the utility model, the shaft sleeve 2 includes a hollow pipe 21 and a limiting sleeve 22 sleeved and installed outside the hollow pipe 21, a shaft hole 23 matched with the rotating shaft 1 in size is formed in the middle of the hollow pipe 21, a plurality of tooth portions 24 and limiting spaces 25 are formed on the outer surface of the limiting sleeve 22 at equal intervals, and the tooth portions 24 and the limiting spaces 25 are staggered. The shaft hole 23 of the hollow pipe 21 is accurately matched with the rotating shaft 1, ensuring that the two are closely matched and can rotate smoothly relative to each other, effectively transmitting torque, and the tooth portions 24 and the limiting spaces 25 on the outer surface of the limiting sleeve 22 are not only distributed at equal intervals in number, but also staggered in layout. The design that the width of the tooth portion 24 gradually increases from inside to outside along the radial direction ensures that, during the installation of the rotor core 3, the closer to the outside of the shaft sleeve 2, the tighter the combination of the tooth portion 24 and the tooth slot 31 of the rotor core 3, thereby ensuring the installation accuracy and stability of the rotor core 3 on the shaft sleeve 2 and effectively preventing displacement or loosening of the rotor core 3 during operation.

[0033] In some embodiments of the utility model, the limiting sleeve 22 has an injection molding gap 26 which is opened along the axial direction when viewed from above, the position of the injection molding gap 26 coincides with the middle position of the limiting space 25, and the radial dimension of the injection molding gap 26 to the shaft center of the limiting sleeve 22 is smaller than the radial dimension of the limiting space 25 to the shaft center of the limiting sleeve 22. The injection molding gap 26 is designed ingeniously, and in the injection molding process, the injection molding material can smoothly fill the limiting space 25 and other parts needing injection molding through the injection molding gap 26, ensuring that the injection molding body is tightly combined with each part, enhancing the overall structural strength, and at the same time, avoiding affecting the dynamic balance performance of the rotor due to excessive or uneven distribution of the injection molding material. In addition, as shown in Figure 4 、 Figure 5 The end angles of the tooth part 24, the limiting space 25 and the injection molding gap 26 are all rounded, effectively reducing stress concentration, improving the mechanical properties and service life of the shaft sleeve 2, and reducing the risk of component damage due to stress concentration in the high-speed rotation process.

[0034] In some embodiments of the utility model, the shaft sleeve 2 is made of a non-magnetic material, which effectively avoids the formation of a magnetic circuit loop, reduces the magnetic leakage phenomenon, and improves the magnetic performance and efficiency of the motor. At the same time, the reasonable structural design ensures the dynamic balance performance of the rotor, reduces the vibration and noise of the motor during operation, improves the operation stability and precision of the motor, and helps to improve the working performance of the motor in various application scenarios.

[0035] The improvement of the structural strength of the rotor in the scheme is that the effective connection and positioning of the shaft sleeve 2 to the rotor core 3, and the tight combination of the rotor injection molding body 5 with each part, make the overall structural strength of the rotor significantly higher than that of the traditional design. When subjected to external forces such as torque and centrifugal force, the connection between the components is more stable and less likely to loosen, deform or be damaged, effectively improving the reliability and service life of the motor. For example, in the comparative test, the rotor core 3 of the similar prior art deforms when the torque reaches 634N without plastic wrapping, while the scheme deforms only when the torque reaches 1377N, and some alternative schemes can even reach 3717N, fully demonstrating the structural strength advantage.

[0036] In some embodiments of the utility model, the rotor core 3 is in a triangular structure, and the rotor core 3 has an injection molding through hole 32 which is opened along the axial direction of the shaft sleeve 2 when viewed from above. While ensuring the performance of the magnetic circuit, the triangular structure of the rotor core 3 is more convenient for processing, manufacturing and installation than other complex shapes. The injection molding through hole 32 provides a good connection point for the rotor injection molding body 5, and the injection molding connecting column 51 formed inside the rotor injection molding body 5 corresponding to the injection molding through hole 32 tightly cooperates with the injection molding through hole 32, further enhancing the connection strength of the rotor core 3 and the rotor injection molding body 5, and making the entire rotor structure more stable.

[0037] The cost is reduced and the production efficiency is improved in the scheme, the triangular structure of the rotor core 3 is simple and the area is reduced, the complexity and cost of the mold are reduced in the mold manufacturing, the utilization rate of the mold is improved, and the production cycle is shortened. In the assembly process, the structure design of each part is convenient for operation, such as the cooperation of the tooth part 24 of the shaft sleeve 2 and the rotor core 3 with the tooth groove 31, the design of the injection molding gap 26 is convenient for injection molding, and the like, the assembly time and the labor cost are reduced, and the production efficiency is improved, so that the product cost is reduced as a whole, and the competitiveness of the product in the market is enhanced.

[0038] In some embodiments of the utility model, the shaft sleeve 2 is split type structure or integral type structure.

[0039] In the operation process of the brushless motor with the rotor structure, the current passes through the stator winding to generate a rotating magnetic field, the magnetic tile 4 placed between the rotor cores 3 interacts with the stator magnetic field to generate electromagnetic force, the shaft sleeve 2 as the key part connecting the rotor core 3 and the rotating shaft 1, on the one hand, through the close cooperation of the tooth part 24 and the tooth groove 31 of the rotor core 3, ensures that the rotor core 3 can rotate synchronously with the shaft sleeve 2, effectively converts the electromagnetic force into rotating torque, on the other hand, its non-magnetic characteristic avoids the interference to the magnetic field and the occurrence of magnetic leakage phenomenon, ensures the magnetic performance and efficiency of the motor. The rotor injection body 5 plays the role of protecting and reinforcing the internal components externally, prevents the displacement or damage of the components due to centrifugal force and other factors in the high-speed rotating process, ensures the stable operation of the rotor, so that the efficient and stable power output of the motor is realized.

[0040] In the description of the specification, the description of the terms "one embodiment", "example", "specific example" and the like means that the specific features, structures, materials or characteristics described in combination with the embodiment or example are contained in at least one embodiment or example of the utility model. In the specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable way.

[0041] The above is only an example and description of the utility model, and those skilled in the art can make various modifications or supplements or adopt similar ways to replace the described specific embodiments, as long as they do not deviate from the scope defined by the utility model or exceed the scope defined by the utility model. The claims, and all the protection scope of the utility model should belong to the protection scope of the utility model.

Claims

1. A high-strength brushless motor rotor structure, comprising a shaft, a bushing, a rotor core, magnets, and a rotor injection-molded body, characterized in that, The bushing is coaxially mounted on the outside of the rotating shaft. The surface of the bushing has teeth and a limiting space. Multiple rotor cores are stacked along the axial direction of the bushing. The surface of the rotor core has tooth grooves that match the teeth. The width of the teeth gradually increases from the inside to the outside along the radial direction of the bushing. The magnetic tiles are placed between adjacent rotor cores. The size of the magnetic tiles matches the size of the limiting space. The rotor injection molded body is injection molded on the surface of the assembly formed by the rotating shaft, bushing, rotor cores and magnetic tiles.

2. The high-strength brushless motor rotor structure according to claim 1, characterized in that, The bushing includes a hollow tube and a limiting sleeve fitted and installed outside the hollow tube. The hollow tube has a through hole in the middle that matches the size of the rotating shaft. The outer surface of the limiting sleeve has a plurality of teeth and limiting spaces formed at equal intervals, and the teeth and limiting spaces are staggered.

3. The high-strength brushless motor rotor structure according to claim 2, characterized in that, The limiting sleeve has an injection notch that extends through it along its axial direction when viewed from above. The position of the injection notch coincides with the middle position of the limiting space, and the radial dimension from the injection notch to the axis of the limiting sleeve is smaller than the radial dimension from the limiting space to the axis of the limiting sleeve.

4. The high-strength brushless motor rotor structure according to claim 3, characterized in that, The corners of the teeth, the limiting space, and the injection notch are all rounded.

5. A high-strength brushless motor rotor structure according to claim 1, characterized in that, The rotor core has a triangular structure and has an injection-molded through hole that extends axially along the bushing when viewed from above.

6. A high-strength brushless motor rotor structure according to claim 5, characterized in that, The rotor injection body has an injection connection post with a size matching the injection through hole inside.

7. The high-strength brushless motor rotor structure according to claim 1, characterized in that, The bushing can be a split structure or an integral structure.

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