Motor rotor with inner and outer iron cores

Abstract

A motor rotor with an inner iron core and an outer iron core comprises a rotor shaft, the inner iron core and the outer iron core, the inner iron core is circumferentially fixed on the rotor shaft, a U-shaped magnetic steel groove is arranged between the outer iron core and the inner iron core, three pieces of magnetic steel are arranged in the U-shaped magnetic steel groove, the first magnetic steel and the third magnetic steel are symmetrically arranged on two sides in the U-shaped magnetic steel groove, and the inner iron core and the outer iron core are arranged in the U-shaped magnetic steel groove. Wherein the second magnetic steel is arranged between the first magnetic steel and the third magnetic steel and located at the groove bottom of the U-shaped magnetic steel groove, and the circumferential outer walls of the inner iron core and the outer iron core are wrapped with carbon fiber layers used for fixing the inner iron core, the outer iron core and the magnetic steel.

Description

Technical Field

[0001] The utility model belongs to the field of electric vehicles, and particularly relates to a motor rotor with inner and outer iron cores. Background Art

[0002] The drive motor is a key component of electric vehicles, and the high speed of the motor has gradually become an important research direction. At present, many rotors use adhesive to fix the permanent magnet to the outer surface of the core. When the rotor speed is high, the centrifugal force on the permanent magnet increases, and the high-frequency vibration of the permanent magnet will seriously affect the service life of the rotor. At the same time, it will cause stress concentration, rotor leakage, and even the risk of permanent magnets coming out. When the rotor rotates at high speed, it will generate a lot of heat, which has a great impact on the performance of the motor. Therefore, how to enhance the heat dissipation of the motor, improve the stability and safety of the motor, and the working efficiency of the motor has become the primary concern of everyone. Summary of the invention

[0003] The purpose of the utility model is to address the problems existing in the prior art and to propose a motor rotor with inner and outer iron cores. The rotor divides the iron core into inner and outer iron cores, and a U-shaped magnetic steel slot is arranged between the inner and outer iron cores. Three magnetic steels can be arranged in the U-shaped magnetic steel slot, wherein the first magnetic steel and the third magnetic steel are symmetrically arranged, and the second magnetic steel is arranged between the first and third magnetic steels and is located at the bottom of the U-shaped magnetic steel slot. The U-shaped magnetic steel slot shortens the radial thickness of the outer iron core, increases the magnetic flux density of the outer iron core, and thus increases the efficiency of the motor.

[0004] The purpose of the utility model is achieved in this way.

[0005] A motor rotor with inner and outer iron cores comprises a rotor shaft, inner and outer iron cores, wherein the inner iron core is circumferentially fixed on the rotor shaft, a U-shaped magnetic steel groove is arranged between the outer iron core and the inner iron core, three magnetic steels are arranged in the U-shaped magnetic steel groove, wherein the first magnetic steel and the third magnetic steel are symmetrically arranged on both sides of the U-shaped magnetic steel groove, wherein the second magnetic steel is arranged between the first and third magnetic steels and is located at the bottom of the U-shaped magnetic steel groove, and the circumferential outer walls of the inner and outer iron cores are wrapped with carbon fiber layers for fixing the inner iron core, the outer iron core and the magnetic steel.

[0006] Furthermore, the extension direction of the second magnetic steel is perpendicular to the direction of the symmetry line of the U-shaped magnetic steel groove.

[0007] Furthermore, the included angle between the extension direction of the first magnetic steel and the third magnetic steel and the symmetry line of the U-shaped magnetic steel groove is 22°.

[0008] Furthermore, a V-shaped magnetic steel groove is arranged on the outer core, the V-shaped magnetic steel groove is located at the outer layer of the U-shaped magnetic steel groove, and the fourth magnetic steel and the fifth magnetic steel are symmetrically arranged in the V-shaped magnetic steel groove.

[0009] Furthermore, the included angle between the fourth magnetic steel, the fifth magnetic steel and the symmetry line of the V-shaped magnetic steel groove is 74°.

[0010] Furthermore, both axial ends of the inner iron core and the outer iron core are provided with limiters, the limiters are circumferentially fixed to the rotor shaft, the carbon fiber layer is wrapped around the circumferential outer wall of the limiter, and a limiting flange is provided on the limiter, and the limiting flange is used to limit the axial position of the carbon fiber layer.

[0011] Furthermore, a plurality of weight-reducing holes are provided on the inner iron core and the outer iron core, and the weight-reducing holes extend axially along the inner iron core and the outer iron core.

[0012] Furthermore, the carbon fiber layer is wrapped by wet winding.

[0013] Furthermore, the thickness of the carbon fiber layer is 2-2.2 mm.

[0014] By adopting the above scheme, the outer walls of the inner and outer iron cores of the utility model are wrapped with carbon fiber layers to fix the inner iron core, the outer iron core and the magnetic steel. The carbon fiber material can effectively reduce the rotor temperature, effectively reduce heat conduction, reduce the risk of magnetic steel demagnetization, and reduce centrifugal deformation at high speed, thereby extending the service life of the motor and increasing the rotor magnetic flux. Under the same input current, the motor speed is increased; the double-layer magnetic steel slot structure improves the power density of the rotor and effectively reduces leakage magnetic flux; and the inner U and outer V structure shortens the radial thickness of the outer iron core, improves the magnetic resistance torque, optimizes the magnetic concentration effect, increases the magnetic flux density, makes the magnetic density more uniform, and reduces the saturation area. The utilization rate of the magnetic material is improved, and the uniform distribution of the magnetic circuit can be ensured; the motor rotor structure of the inner and outer iron cores is simple and easy to promote.

[0015] The utility model is further described below in conjunction with the accompanying drawings and specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Carbon fiber layer 1, rotor shaft 2, limiter 3, V-shaped magnetic steel slot 4, U-shaped magnetic steel slot 5, outer iron core 6, inner iron core 7, first magnetic steel 8a, second magnetic steel 8b, third magnetic steel 8c, fourth magnetic steel 8d, fifth magnetic steel 8e, locking nut 9, weight reduction hole 10.

[0017] Figure 1 It is a structural schematic diagram of the utility model.

[0018] Figure 2 It is a schematic diagram of the assembly of the iron core and the carbon fiber layer of the utility model.

[0019] Figure 3 for Figure 2 Schematic diagram of direction A.

[0020] Figure 4 for Figure 3Enlarged view of point B in the middle. DETAILED DESCRIPTION

[0021] See also Figures 1 to 4 A motor rotor with inner and outer iron cores includes a rotor shaft 2, inner and outer iron cores, wherein the inner iron core 7 and the outer iron core 6 are provided with a plurality of weight-reducing holes 10, and the weight-reducing holes 10 extend axially along the inner iron core 7 and the outer iron core 6, and the weight-reducing holes make the rotor lighter. The inner iron core 7 is circumferentially fixed on the rotor shaft 2, and a U-shaped magnetic steel slot 5 is arranged between the outer iron core 6 and the inner iron core 7. Three magnetic steels are arranged in the U-shaped magnetic steel slot 5, wherein the first magnetic steel 8a and the third magnetic steel 8c are symmetrically arranged on both sides of the U-shaped magnetic steel slot 5, wherein the second magnetic steel 8b is arranged between the first and the third magnetic steels, and is located at the bottom of the U-shaped magnetic steel slot 5. In this embodiment, the extension direction of the second magnetic steel 8b is perpendicular to the direction of the symmetry line of the U-shaped magnetic steel slot 5, and the extension direction of the first magnetic steel 8a and the third magnetic steel 8c and the symmetry line of the U-shaped magnetic steel slot 5 are at an angle of 22°. Compared with the V-shaped, the U-shaped magnetic steel slot 5 shortens the radial length of the outer iron core 6, and can increase the magnetic flux density of the outer iron core 6, thereby improving the working efficiency of the motor. The circumferential outer wall of the inner and outer cores is wrapped with a carbon fiber layer 1, which is used to fix the inner core 7, the outer core 6, and the magnetic steel. Further, the wrapping method of the carbon fiber layer 1 is wet winding, and the thickness of the carbon fiber layer 1 is 2-2.2mm. After wrapping the carbon fiber layer 1, the motor rotor temperature can be effectively reduced, and the heat conduction can be effectively reduced. While reducing the risk of magnetic steel demagnetization, the centrifugal deformation at high speed can be reduced, and the motor speed can be increased under the same input current. Further, both axial ends of the inner core 7 and the outer core 6 are provided with a limiter 3, and the limiter 3 is circumferentially fixed to the rotor shaft 2. The carbon fiber layer 1 is wrapped around the circumferential outer wall of the limiter 3. The limiter 3 is provided with a limit flange, and the limit flange is used to axially limit the carbon fiber layer 1. The limiter 3 is locked and fixed by a locking nut 9. The function of the limiter 3 is to form an axial limit for the magnetic steel, the outer core 6, and the carbon fiber layer 1.

[0022] Furthermore, the outer core 6 is provided with a V-shaped magnetic steel slot 4, the V-shaped magnetic steel slot 4 is located at the outer layer of the U-shaped magnetic steel slot 5, and the fourth magnetic steel 8d and the fifth magnetic steel 8e are symmetrically arranged in the V-shaped magnetic steel slot 4. In this embodiment, the angle between the fourth magnetic steel 8d, the fifth magnetic steel 8e and the symmetry line of the V-shaped magnetic steel slot 4 is 74°. The advantage of setting a double-layer magnetic steel slot is that the rotor power density is improved and the leakage magnetic flux is effectively reduced. The structure of inner U and outer V shortens the radial thickness of the outer core, improves the magnetic resistance torque, optimizes the magnetic concentration effect, increases the magnetic flux density, makes the magnetic density more uniform, and reduces the saturation area. It improves the utilization rate of magnetic materials and ensures uniform distribution of the magnetic circuit.

[0023] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modification made to the present invention by those skilled in the art without departing from the spirit of the present invention shall fall within the protection scope of the present invention.

Claims

1. A motor rotor with inner and outer iron cores, comprising a rotor shaft (2), inner and outer iron cores, characterized in that: The inner iron core (7) is circumferentially fixed on the rotor shaft (2); a U-shaped magnetic steel slot (5) is arranged between the outer iron core (6) and the inner iron core (7); three magnetic steels are arranged in the U-shaped magnetic steel slot (5); a first magnetic steel (8a) and a third magnetic steel (8c) are symmetrically arranged on both sides of the U-shaped magnetic steel slot (5); and a second magnetic steel (8b) is arranged between the first and third magnetic steels and located at the bottom of the U-shaped magnetic steel slot (5); and the circumferential outer walls of the inner and outer iron cores are wrapped with a carbon fiber layer (1) for fixing the inner iron core (7), the outer iron core (6) and the magnetic steel.

2. The motor rotor with inner and outer iron cores according to claim 1, characterized in that: The extension direction of the second magnetic steel (8b) is perpendicular to the direction of the symmetry line of the U-shaped magnetic steel slot (5).

3. The motor rotor with inner and outer iron cores according to claim 1, characterized in that: The included angle between the extension direction of the first magnetic steel (8a) and the third magnetic steel (8c) and the symmetry line of the U-shaped magnetic steel slot (5) is 22°.

4. The motor rotor with inner and outer iron cores according to claim 1, characterized in that: The outer iron core (6) is provided with a V-shaped magnetic steel groove (4), the V-shaped magnetic steel groove (4) is located on the outer layer of the U-shaped magnetic steel groove (5), and the fourth magnetic steel (8d) and the fifth magnetic steel (8e) are symmetrically arranged in the V-shaped magnetic steel groove (4).

5. The motor rotor with inner and outer iron cores according to claim 4, characterized in that: The included angle between the fourth magnetic steel (8d), the fifth magnetic steel (8e) and the symmetry line of the V-shaped magnetic steel groove (4) is 74°.

6. The motor rotor with inner and outer iron cores according to claim 1, characterized in that: Both axial ends of the inner iron core (7) and the outer iron core (6) are provided with limiters (3), the limiters (3) are circumferentially fixed to the rotor shaft (2), the carbon fiber layer (1) is wrapped around the circumferential outer wall of the limiter (3), and the limiter (3) is provided with a limit flange, which is used to axially limit the carbon fiber layer (1).

7. The motor rotor with inner and outer iron cores according to claim 1, characterized in that: A plurality of weight-reducing holes (10) are provided on the inner iron core (7) and the outer iron core (6), and the weight-reducing holes (10) extend axially along the inner iron core (7) and the outer iron core (6).

8. The motor rotor with inner and outer iron cores according to claim 1, characterized in that: The carbon fiber layer (1) is wrapped by wet winding.

9. The motor rotor with inner and outer iron cores according to claim 1, characterized in that: The thickness of the carbon fiber layer (1) is 2-2.2 mm.

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