Rotor structure of differential motor

Abstract

The utility model provides a rotor structure of a differential motor, and belongs to the technical field of motors, the rotor structure comprises a rotor core, a permanent magnet and a rotating shaft, the rotor core is of a disc structure, a shaft hole is formed in the center of the rotor core, and a plurality of mounting grooves are annularly and uniformly distributed in the periphery of the rotor core; a plurality of axial grooves are uniformly distributed on the outer circumference of the rotor iron core; the permanent magnets are fixedly mounted in the mounting grooves in an embedded manner, and the permanent magnets and the mounting grooves are the same in shape and are in close fit; and the rotating shaft is tightly matched with the shaft hole. The structure can accelerate air flow in the air gap, change the air flow direction, increase the relative speed of air in the air gap and the surface of the rotor, and further achieve the effect of enhancing air gap heat dissipation. The structure reduces the working temperature of the rotor permanent magnet, and prolongs the service life of the permanent magnet, the rotor and the motor body.

Description

Technical Field

[0001] The present application belongs to the technical field of permanent magnet motors and relates to a bicycle hub motor, specifically a rotor structure of a differential motor. Background Art

[0002] The wheel hub is an important driving component on the vehicle, bearing most of the load generated during the vehicle's driving. The use of steel wheel hubs can ensure good load-bearing capacity. The rotor is a key component of the motor, and its performance directly affects the overall performance of the equipment. At present, the existing rotors generally have problems such as low efficiency, high energy consumption, and short life, which cannot meet the needs of modern rapid development.

[0003] At present, the steel hub motors on the market generally have two obvious disadvantages: first, the hub motors sealed by steel materials are not conducive to heat dissipation; second, there are many spare parts and the manufacturing process is complicated, resulting in high manufacturing costs. Summary of the invention

[0004] The purpose of the present application is to overcome the deficiencies of the prior art and to provide a rotor structure of a differential motor with high efficiency, low energy consumption and long life.

[0005] A rotor structure of a differential motor, comprising

[0006] The rotor core is a disc structure, an axial hole is arranged at the center of the rotor core, a plurality of mounting grooves are evenly distributed in an annular shape on the outer circumference of the rotor core, and a plurality of axial grooves are evenly distributed on the outer circumference of the rotor core;

[0007] A permanent magnet, wherein the permanent magnet is embedded and fixed in the mounting groove, and the permanent magnet and the mounting groove have the same shape and fit closely;

[0008] A rotating shaft is matched with the shaft hole.

[0009] By adopting the above technical solution, grooves are provided on the outer periphery of the rotor core to improve the heat dissipation performance of the working surface. The rotor structure is simple, and the mounting grooves of the rotor core are integrally made without the need for additional components. The installation efficiency is high. The permanent magnets are embedded and fixed in the rotor core, and have good stability.

[0010] Preferably, the grooves of the rotor core are all arranged between adjacent mounting grooves.

[0011] By adopting the above technical solution, the permanent magnet generates heat during operation, which increases the heat dissipation surface close to the permanent magnet on the rotor core and improves the heat dissipation performance.

[0012] Preferably, a plurality of heat dissipation grooves are annularly spaced apart on the rotor core between the shaft hole and the mounting groove.

[0013] By adopting the above technical solution, the heat dissipation performance is further improved by adding heat dissipation grooves, and the heat dissipation surface close to the permanent magnet is increased in the rotor core around the permanent magnet to improve the heat dissipation effect.

[0014] Preferably, the installation groove is a rectangular groove that passes through the rotor core, and the long sides of the installation groove are perpendicular to the radial direction of the rotor core; the two short sides of the installation groove are formed into a stepped structure.

[0015] By adopting the above technical solution, using a straight-piece permanent magnet and a mounting slot structure, it is easy to rotate and position, and easy to install.

[0016] Preferably, a limiting protrusion is provided in the shaft hole.

[0017] By adopting the above technical solution, a convex block is formed in the shaft hole, which can replace the key connection structure when connected to the rotating shaft, thereby simplifying the installation steps.

[0018] Preferably, the heat dissipation groove is an arc-shaped structure or a fan-shaped structure.

[0019] By adopting the above technical solution, the structure of the heat dissipation groove can be adjusted according to the product size, which is convenient for heat dissipation, reduces the weight of the rotor, and improves the rotor efficiency.

[0020] Preferably, narrow slits are provided on the rotor core between the heat dissipation slots.

[0021] By adopting the above technical solution, the air gap on the rotor is increased, multiple air flows are generated, and heat dissipation is accelerated.

[0022] Preferably, a plurality of circular holes are evenly distributed on the rotor core at the periphery of the heat dissipation slot.

[0023] By adopting the above technical solution, the rotor space is utilized and through holes are provided to accelerate heat dissipation.

[0024] Preferably, the rotor core is made in one piece.

[0025] By adopting the above technical solution, the structure of the rotor core is an integral structure, which can be made in one piece by stamping or casting, so that the subsequent installation is simple and the efficiency is improved; and the rotor core with an integral structure has better mechanical strength and can reduce noise and vibration during rotation.

[0026] In summary, the present application includes at least one of the following beneficial technical effects:

[0027] 1. This structure can accelerate the air flow in the air gap, change the air flow direction, increase the relative speed between the air in the air gap and the rotor surface, and thus achieve the effect of enhancing the heat dissipation of the air gap.

[0028] 2. This structure reduces the working temperature of the rotor permanent magnet and prolongs the working life of the permanent magnet, the rotor and the motor body. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the plan structure of an embodiment of the present structure.

[0030] Figure 2 It is a schematic diagram of the plan structure of another embodiment of the present structure.

[0031] Figure numerals: 1, rotor core; 2, permanent magnet; 3, groove; 4, through hole; 5, shaft hole; 6, round hole; 7, narrow gap. DETAILED DESCRIPTION

[0032] The present application is further described in detail below in conjunction with the accompanying drawings.

[0033] Example 1

[0034] See attached Figure 1 As shown, a rotor structure of a differential motor includes a rotor core 1, a permanent magnet 2 and a rotating shaft.

[0035] The rotor core 1 is a disc structure, and a plurality of mounting grooves are evenly distributed in an annular shape on the outer periphery of the disc. The mounting grooves are all rectangular grooves that penetrate the rotor core 1, and the long sides of the mounting grooves are perpendicular to the radial direction of the rotor core 1; the permanent magnets 2 are fixedly embedded in the mounting grooves, and the permanent magnets 2 are straight sheet magnets whose shapes match the mounting grooves;

[0036] In order to further ensure that the installation is firm and reliable, the two short sides of the installation slot are made into a stepped structure with a wider outer side, and the permanent magnet 2 is set as a T-shaped structure that matches the installation slot.

[0037] An axial hole 5 is provided at the center of the rotor core 1, and a rotating shaft is fixedly installed in the axial hole 5. In this embodiment, a protruding limiting bump is provided on one radial side of the axial hole 5, and the limiting bump can replace the function of the flat key to limit the connection of the rotating shaft; the rotating shaft is made of high-strength material and can withstand the centrifugal force and torque during high-speed rotation.

[0038] On the outer circumferential surface of the rotor core 1, a plurality of grooves 3 are evenly distributed in an annular shape, and the grooves 3 axially penetrate the outer circumferential surface of the rotor core 1; the grooves 3 are arranged between adjacent mounting grooves. The heat dissipation performance of the rotor is improved. The bottom cross section of the groove 3 is a semicircular structure, and the upper part of the groove 3 is a straight groove structure perpendicular to the edge tangent. The depth of the groove is not greater than the distance from the mounting groove to the outer circumference of the rotor core, so as to ensure the supporting force of the mounting groove.

[0039] In order to further improve the heat dissipation capacity of the rotor, a plurality of heat dissipation grooves are arranged at annular intervals on the rotor core 1 between the shaft hole 5 and the mounting groove. In this embodiment, there are four heat dissipation grooves, which are arc-shaped structures and axially penetrate the rotor core 1.

[0040] A plurality of circular holes 6 are arranged at intervals around the outer circumference of the heat dissipation slot. In this embodiment, five circular holes 6 are arranged.

[0041] The structure of the rotor core 1 is integrally formed by stamping or casting. The rotor core 1 can be installed by installing the permanent magnet 2 and the shaft, which simplifies the subsequent assembly and improves the efficiency.

[0042] The rotor core 1 is made of high magnetic permeability material, has good magnetic permeability and mechanical strength, and can improve the efficiency and output power of the motor. Figure 1 The figure shows the planar structure of one end of the rotor core 1. The rotor core 1 may be composed of a plurality of high magnetic permeability material sheets with the same structure stacked to form the integral rotor core 1.

[0043] Working principle of rotor: refers to the mechanism by which the rotor moves under the action of electromagnetic field. Under the action of electromagnetic field, when current passes through the rotor, an induced current will be generated on the surface of the rotor. This induced current will form a magnetic field on the surface of the rotor, which is opposite to the direction of the force generated by the electromagnetic field. The action of these two forces will cause the rotor to move.

[0044] The rotor typically interacts with the electromagnetic field of the stator, the stationary part of the motor, which is also made of a conductive material. The stator's electromagnetic field creates a rotating magnetic field that interacts with the induced currents on the rotor's surface, driving the rotor to rotate.

[0045] The rotor is coaxially installed in the stator, and the rotor and the stator rotate at a relatively high speed, leaving an air gap between the outer circumferential surface of the rotor core 1 and the inner circumference of the stator of the motor. The setting of the groove 3 makes the working surface of the outer circumferential surface of the rotor no longer a continuous smooth arc surface. During the high-speed rotation, the groove 3 will cause the air flow direction in the gap to change, and the turbulence increases the air flow, thereby improving the heat dissipation effect.

[0046] Example 2

[0047] See attached Figure 2 As shown, the difference between this embodiment and embodiment 1 is that the heat dissipation slot is a fan-shaped structure, and there are four heat dissipation slots with a fan-shaped structure in this embodiment. In actual processing, the heat dissipation slot can also be set in other shapes, and the inner and outer edges of the heat dissipation slot match the rotation direction of the rotor.

[0048] The heat sink can not only enhance the heat dissipation capacity, but also reduce the weight of the rotor core, thereby reducing the load and improving the working efficiency of the rotor.

[0049] Narrow slits 7 are provided on the rotor core 1 between adjacent heat dissipation slots.

[0050] A keyway is provided on one radial side of the shaft hole 5, and the rotor core 1 is connected to the rotating shaft via a key.

[0051] Example 3

[0052] The difference between this embodiment and embodiment 1 is that the shaft hole 5 is connected to the rotating shaft by interference fit.

[0053] Example 4

[0054] The difference between this embodiment and embodiment 1 is that the permanent magnet 2 adopts an arc-shaped tile structure.

[0055] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A rotor structure of a differential motor, characterized in that: include A rotor core (1), the rotor core (1) being a disc structure, an axial hole (5) being arranged at the center of the rotor core (1), a plurality of mounting grooves being evenly distributed in an annular shape on the outer circumference of the rotor core (1), and a plurality of axial grooves (3) being evenly distributed on the outer circumference of the rotor core (1); A permanent magnet (2), wherein the permanent magnet (2) is embedded and fixed in the installation groove, and the permanent magnet (2) and the installation groove have the same shape and fit tightly together; A rotating shaft is tightly matched with the shaft hole (5).

2. The rotor structure of the differential motor according to claim 1, characterized in that: The grooves (3) of the rotor core (1) are all arranged between adjacent installation grooves.

3. The rotor structure of the differential motor according to claim 1, characterized in that: A plurality of heat dissipation grooves are arranged at annular intervals on the rotor core (1) between the shaft hole (5) and the mounting groove.

4. The rotor structure of the differential motor according to claim 1, characterized in that: The installation groove is a rectangular groove that passes through the rotor core (1), and the long sides of the installation groove are perpendicular to the radial direction of the rotor core (1); and the two short sides of the installation groove are formed into a stepped structure.

5. The rotor structure of the differential motor according to claim 1, characterized in that: A limiting protrusion is arranged in the shaft hole (5).

6. The rotor structure of the differential motor according to claim 3, characterized in that: The heat dissipation groove is an arc-shaped structure or a fan-shaped structure.

7. The rotor structure of the differential motor according to claim 3, characterized in that: Narrow slits (7) are provided on the rotor core (1) between the heat dissipation grooves.

8. The rotor structure of the differential motor according to claim 3, characterized in that: A plurality of circular holes (6) are evenly distributed on the rotor core (1) at the periphery of the heat dissipation slot.

9. The rotor structure of the differential motor according to any one of claims 1 to 8, characterized in that: The rotor core (1) is made in one piece.

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