Motor rotor and motor

Abstract

The present application provides a motor rotor and a motor. The motor rotor is a surface-mounted rotor, comprising a rotor core (1) and a magnetic steel (2), the rotor core (1) being provided with a mounting groove (3), the magnetic steel (2) being installed in the mounting groove (3), and a first magnetic isolation bridge (4) being provided on the outer circumference of the rotor core (1), the first magnetic isolation bridge (4) being located on the outer circumference of the mounting groove (3) and limiting the position of the magnetic steel (2) in the mounting groove (3). According to the motor rotor of the present application, the rotor structure can be simplified, magnetic leakage can be reduced, and the reliability of high-speed operation of the motor can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of motors, and in particular to a motor rotor and a motor. Background Art

[0002] The installation methods of magnetic steel in motor rotors are mainly divided into surface-mounted and built-in types. Among them, when the magnetic steel is a non-concentric arc surface structure, the no-load air gap magnetic flux waveform tends to be sinusoidal, which can effectively reduce the motor noise. The magnetic steel of the surface-mounted rotor pole directly faces the air gap, which has the advantages of convenient processing and installation. In terms of magnetization, all the magnetic steel can be glued to the surface of the core first, and the rotor can be magnetized as a whole. The structure is simple, the magnetization is convenient, and the assembly process is simple, so the surface-mounted rotor is widely used in the motor industry.

[0003] The magnets of the surface-mounted rotor are glued to the surface of the rotor core with glue. The magnets are subjected to great centrifugal force during the rotation of the motor, so surface-mounted rotors are generally only used in low-speed motors. When the speed is high, in order to prevent the magnets from falling off, a sheath structure needs to be added to the outer circle of the rotor, which increases magnetic leakage and complicates the process. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present application is to provide a motor rotor and a motor, which can simplify the rotor structure, reduce magnetic leakage, and improve the reliability of high-speed operation of the motor.

[0005] In order to solve the above problems, the present application provides a motor rotor, which is a surface-mounted rotor. The motor rotor includes a rotor core and a magnet. The rotor core is provided with a mounting groove, and the magnet is installed in the mounting groove. A first magnetic isolation bridge is provided on the outer circumference of the rotor core. The first magnetic isolation bridge is located on the outer circumference side of the mounting groove and forms a limit on the position of the magnet in the mounting groove.

[0006] Preferably, along the circumference of the rotor core, the first magnetic isolation bridge includes a first bridge section connected to the first side of the mounting slot and a second bridge section connected to the second side of the mounting slot. Along the rotation direction of the motor rotor, the first bridge section is located at the turning front edge of the motor rotor, and the second bridge section is located at the turning rear edge of the motor rotor. The radial thickness of the first bridge section is smaller than the radial thickness of the second bridge section.

[0007] Preferably, a second magnetic isolation bridge is provided between two adjacent mounting grooves, the radial thickness of the first bridge section is Wr1, and the thickness of the second magnetic isolation bridge is Wr0, wherein 0.3 mm ≤ Wr1 ≤ 0.6 mm, and 0.3 mm ≤ Wr0 ≤ 0.6 mm.

[0008] Preferably, the radial thickness of the first bridge segment is Wr1, and the radial thickness of the second bridge segment is Wr2, wherein 0.3 mm ≤ Wr1 ≤ 0.6 mm, and 1.2 Wr1 ≤ Wr2 ≤ 1.8 Wr1.

[0009] Preferably, the central angle occupied by the second bridge section is b, wherein 0.1a≤b≤0.25a, ​​a=360° / n, and n is the number of rotor poles.

[0010] Preferably, in a cross section perpendicular to the central axis of the rotor core, the distance between the side of the mounting groove close to the central axis and the central axis is H1, the outer radius of the rotor core is H2, the thickness of the magnetic steel on the d-axis is Wpm1, the thickness of the magnetic steel at both ends is Wpm2, the length of the side of the magnetic steel close to the central axis is Lpm, and the length of the side of the mounting groove close to the central axis is Lc, wherein,

[0011] 0.14H2≤Wpm1≤0.26H2;

[0012] 0.8Wpm1≤Wpm2≤0.8Wpm1;

[0013] 0.45Lc≤Lpm≤0.65Lc;

[0014] H1=H2-Wr1-Wpm1;

[0015] Lc=H1 / arctan(a / 2);

[0016] a=360° / n.

[0017] Preferably, the magnetic steel is glued and fixed in the mounting groove.

[0018] Preferably, the gap between the magnetic steel and the side wall of the mounting groove is filled with filling material.

[0019] Preferably, two protrusions are provided on the side of the installation groove close to the central axis, and the magnetic steel is limited between the two protrusions.

[0020] According to another aspect of the present application, a motor is provided, including a motor rotor, which is the motor rotor described above.

[0021] The motor rotor provided in the present application is a surface-mounted rotor, and the motor rotor includes a rotor core and a magnet. The rotor core is provided with a mounting groove, and the magnet is installed in the mounting groove. The outer circumference of the rotor core is provided with a first magnetic isolation bridge, and the first magnetic isolation bridge is located on the outer circumference of the mounting groove, and forms a limit for the position of the magnet in the mounting groove. The motor rotor in the present application is provided with a layer of magnetic isolation bridge on the outer circumference, and there is no need for subsequent assembly, which can improve the high-speed operation reliability of the surface-mounted rotor, simplify the rotor process, and save costs. The existence of the magnetic isolation bridge can also reduce the leakage of the motor rotor and improve the working efficiency of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a structural dimension diagram of the motor rotor of an embodiment of the present application;

[0023] Figure 2 This is a structural dimension diagram of the motor rotor of an embodiment of the present application;

[0024] Figure 3 A cross-sectional structural diagram of a motor rotor according to an embodiment of the present application;

[0025] Figure 4 A cross-sectional structural diagram of a motor rotor according to an embodiment of the present application;

[0026] Figure 5 A diagram showing the magnetic field lines of the motor according to an embodiment of the present application;

[0027] Figure 6 This is a diagram showing the magnetic field lines of a traditional internal magnetic steel motor.

[0028] The reference numerals are:

[0029] 1. Rotor core; 2. Magnetic steel; 3. Mounting slot; 4. First magnetic isolation bridge; 5. First bridge section; 6. Second bridge section; 7. Second magnetic isolation bridge; 8. Filling material; 9. Bump; 10. Motor rotor; 11. Motor stator. DETAILED DESCRIPTION

[0030] See also Figures 1 to 5 As shown, according to an embodiment of the present application, the motor rotor is a surface-mounted rotor, and the motor rotor includes a rotor core 1 and a magnet 2. The rotor core 1 is provided with a mounting groove 3, and the magnet 2 is installed in the mounting groove 3. A first magnetic isolation bridge 4 is provided on the outer circumference of the rotor core 1. The first magnetic isolation bridge 4 is located on the outer circumferential side of the mounting groove 3, and forms a limit on the position of the magnet 2 in the mounting groove 3.

[0031] The motor rotor in the present application is provided with a magnetic isolation bridge on the outer circle, which can limit the installation position of the magnet 2 in the installation groove 3 and effectively prevent the magnet 2 from falling off. The magnetic isolation bridge is directly formed on the rotor core 1 without the need for subsequent assembly, thereby improving the high-speed operation reliability of the surface-mounted rotor, simplifying the rotor process and saving costs. The existence of the magnetic isolation bridge can also reduce the leakage magnetic field of the motor rotor and improve the working efficiency of the motor.

[0032] In one embodiment, along the circumference of the rotor core 1, the first magnetic isolation bridge 4 includes a first bridge section 5 connected to the first side of the mounting slot 3 and a second bridge section 6 connected to the second side of the mounting slot 3. Along the rotation direction of the motor rotor, the first bridge section 5 is located at the turning front edge of the motor rotor, and the second bridge section 6 is located at the turning rear edge of the motor rotor. The radial thickness of the first bridge section 5 is smaller than the radial thickness of the second bridge section 6.

[0033] In this embodiment, the armature reaction principle is used to make the thickness of the magnetic isolation bridge on both sides of the circumference of the magnetic steel 2 of each pole of the motor rotor different, forming an asymmetric magnetic isolation bridge structure. The magnetic bridge at the front edge of the motor is thin, and the magnetic bridge at the rear edge is thick. The thick magnetic isolation bridge can form leakage magnetic field to the magnetic circuit, thereby effectively improving the anti-demagnetization ability of the magnetic steel at the rear edge of the turning, that is, the demagnetization side, and effectively solving the problem of easy demagnetization of the surface-mounted rotor. Since the overall thickness of the magnetic isolation bridge is relatively thin, it will not form a large amount of leakage magnetic field on the outside of the built-in motor rotor magnetic steel, affecting the motor efficiency.

[0034] A second magnetic isolation bridge 7 is arranged between two adjacent mounting grooves 3. The second magnetic isolation bridge 7 is a magnetic bridge between rotor poles. The radial thickness of the first bridge section 5 is Wr1, and the thickness of the second magnetic isolation bridge 7 is Wr0, wherein 0.3mm≤Wr1≤0.6mm, 0.3mm≤Wr0≤0.6mm, which can reasonably limit the thickness of the first bridge section 5 of the first magnetic isolation bridge 4 and the thickness of the second magnetic isolation bridge 7. When Wr1 and Wr0 are too small, the rotor structure strength is low and it is easy to break at high speed; when Wr1 and Wr0 are too large, the magnetic isolation bridge has serious magnetic leakage and the motor efficiency is low; when 0.3mm≤Wr1≤0.6mm and 0.3mm≤Wr0≤0.6mm, the motor structure strength can meet the high-speed operation, and the magnetic isolation bridge has less magnetic leakage, and the motor efficiency is high.

[0035] Figure 2 The direction of the middle arrow is the direction of the motor rotation. According to the motor armature reaction principle, during the operation of the motor, the magnetic steel 2 at the leading edge of the motor rotation direction is in a magnetized state, and the magnetic steel 2 at the trailing edge of the motor rotation direction is in a demagnetized state. By increasing the thickness of the second bridge section 6 at the trailing edge of the motor rotation direction, a part of the stator magnetic field can be leaked from the second bridge section 6, reducing the demagnetization effect of the trailing edge magnetic steel 2 and improving the anti-demagnetization ability of the motor.

[0036] The radial thickness of the first bridge section 5 is Wr1, the radial thickness of the second bridge section 6 is Wr2, wherein 0.3 mm ≤ Wr1 ≤ 0.6 mm, 1.2 Wr1 ≤ Wr2 ≤ 1.8 Wr1, the center angle occupied by the second bridge section 6 is b, wherein 0.1 a ≤ b ≤ 0.25 a, a = 360° / n, n is the number of rotor poles, and a is the center angle occupied by each magnetic pole.

[0037] When the thickness Wr2 of the second bridge section 6 at the rear edge is small and the center angle b occupied is also small, the anti-demagnetization capability of the rotor will be low. When the thickness Wr2 of the second bridge section 6 at the rear edge is too large and the center angle b occupied is also too large, the rotor leakage will seriously affect the motor performance. By limiting the above-mentioned dimensional relationship, the thickness Wr2 of the second bridge section 6 and the center angle b occupied by the second bridge section 6 can be associated, so that the structures of the two interact with each other and can be in a suitable value range, thereby improving the working performance of the motor and ensuring the anti-demagnetization capability of the magnetic steel 2.

[0038] In the cross section perpendicular to the central axis of the rotor core 1, the distance between the side of the installation slot 3 close to the central axis and the central axis is H1, the outer radius of the rotor core 1 is H2, the thickness of the magnetic steel 2 on the d-axis is Wpm1, the thickness of the magnetic steel 2 at both ends is Wpm2, the length of the side of the magnetic steel 2 close to the central axis is Lpm, and the length of the side of the installation slot 3 close to the central axis is Lc, wherein,

[0039] 0.14H2≤Wpm1≤0.26H2;

[0040] 0.8Wpm1≤Wpm2≤0.8Wpm1;

[0041] 0.45Lc≤Lpm≤0.65Lc;

[0042] H1=H2-Wr1-Wpm1;

[0043] Lc=H1 / arctan(a / 2);

[0044] a=360° / n.

[0045] In this embodiment, the outer arc of the magnetic steel 2 is an eccentric arc structure that is eccentric relative to the central axis of the rotor core 1. The structure of the magnetic steel 2 is thick in the center and thin on both sides. The center of the outer arc of the magnetic steel 2 is located on the d-axis.

[0046] Through the above-mentioned dimensional relationship, the outer diameter of the motor rotor can be used to determine the groove type of the motor rotor installation groove and the outer dimensions of the magnetic steel, thereby improving the motor performance while reducing the amount of magnetic steel used, reducing costs, and ensuring that the motor has better noise performance.

[0047] In one embodiment, the magnetic steel 2 can be fixed in the mounting groove 3 by gluing, thereby further enhancing the assembly strength between the magnetic steel 2 and the mounting groove 3 .

[0048] See also Figure 3 As shown, in one embodiment, the gap between the magnetic steel 2 and the side wall of the mounting groove 3 is filled with a filling material 8, so that the filling material 8 can be used to increase the contact area between the magnetic steel 2 and the mounting groove 3, and enhance the stability and reliability of the mounting structure of the magnetic steel 2 in the mounting groove 3. The filling material 8 is, for example, epoxy glue.

[0049] See also Figure 4As shown, in one embodiment, two protrusions 9 are provided on the side of the mounting groove 3 close to the central axis, and the magnetic steel 2 is limited between the two protrusions 9. In this embodiment, the position of the magnetic steel 2 in the circumferential direction can be limited by the two protrusions 9, and the position of the magnetic steel 2 in the radial direction can be limited by the mounting groove 3, so that the magnetic steel 2 is stably and reliably limited in the mounting groove 3.

[0050] See also Figure 5 As shown, according to an embodiment of the present application, the motor includes a motor rotor 10 and a motor stator 11 . The motor rotor 10 is the above-mentioned motor rotor, and the motor rotor 10 is sleeved in the motor stator 11 .

[0051] See also Figure 6 As shown in the figure, the curve with arrows is the magnetic force line. It can be seen from the figure that for the traditional magnetic steel internal rotor, the thickness of the magnetic isolation bridge outside the magnetic steel slot is very large, so a large amount of magnetic leakage will be formed at the magnetic isolation bridge. For the surface-mounted rotor of this embodiment, its structure determines that the thickness of the magnetic isolation bridge located on the outer circumference will be very thin, see Figure 5 As shown, the curve with arrows in the figure is the magnetic line of force. It can be seen from the figure that the thickness of the magnetic isolation bridge located on the outer circumference of the motor rotor of the embodiment of the present application is very thin, and the leakage magnetic flux formed is less, so the motor performance is higher. In the motor of the embodiment of the present application, the thickness of the magnetic isolation bridge on the left and right sides of each pole is different. The magnetic isolation bridges at two locations of the magnetic steel in the demagnetization part are thicker, which can effectively leak a part of the magnetic field, ensure the anti-demagnetization ability of the motor, and the motor performance is better than that of the traditional built-in motor.

[0052] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0053] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application. The above are only preferred implementations of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present application, and these improvements and variations should also be regarded as the protection scope of the present application.

Claims

1. A motor rotor, characterized in that: The motor rotor is a surface-mounted rotor, comprising a rotor core (1) and a magnetic steel (2), the rotor core (1) being provided with a mounting groove (3), the magnetic steel (2) being mounted in the mounting groove (3), a first magnetic isolation bridge (4) being provided on the outer circumference of the rotor core (1), the first magnetic isolation bridge (4) being located on the outer circumference side of the mounting groove (3) and limiting the position of the magnetic steel (2) in the mounting groove (3); Along the circumference of the rotor core (1), the first magnetic isolation bridge (4) comprises a first bridge section (5) connected to a first side of the mounting slot (3) and a second bridge section (6) connected to a second side of the mounting slot (3); along the rotation direction of the motor rotor, the first bridge section (5) is located at a turning front edge of the motor rotor, and the second bridge section (6) is located at a turning rear edge of the motor rotor; the radial thickness of the first bridge section (5) is smaller than the radial thickness of the second bridge section (6).

2. The motor rotor according to claim 1, characterized in that: A second magnetic isolation bridge (7) is provided between two adjacent installation grooves (3), the radial thickness of the first bridge section (5) is Wr1, and the thickness of the second magnetic isolation bridge (7) is Wr0, wherein 0.3 mm ≤ Wr1 ≤ 0.6 mm, and 0.3 mm ≤ Wr0 ≤ 0.6 mm.

3. The motor rotor according to claim 1, characterized in that: The radial thickness of the first bridge segment (5) is Wr1, and the radial thickness of the second bridge segment (6) is Wr2, wherein 0.3 mm ≤ Wr1 ≤ 0.6 mm, and 1.2 Wr1 ≤ Wr2 ≤ 1.8 Wr1.

4. The motor rotor according to claim 1, characterized in that: The central angle occupied by the second bridge section (6) is b, wherein 0.1a≤b≤0.25a, ​​a=360° / n, and n is the number of rotor poles.

5. The motor rotor according to claim 1, characterized in that: In a cross section perpendicular to the central axis of the rotor core (1), the distance between the side of the mounting groove (3) close to the central axis and the central axis is H1, the outer radius of the rotor core (1) is H2, the thickness of the magnetic steel (2) on the d-axis is Wpm1, the thickness of the magnetic steel (2) at both ends is Wpm2, the length of the side of the magnetic steel (2) close to the central axis is Lpm, and the length of the side of the mounting groove (3) close to the central axis is Lc, wherein: 0.14H2≤Wpm1≤0.26H2; 0.8Wpm1≤Wpm2≤0.8Wpm1; 0.45Lc≤Lpm≤0.65Lc; H1=H2-Wr1-Wpm1; Lc=H1 / arctan(a / 2); a=360° / n.

6. The motor rotor according to claim 1, characterized in that: The magnetic steel (2) is glued and fixed in the installation groove (3).

7. The motor rotor according to claim 1, characterized in that: The gap between the magnetic steel (2) and the side wall of the installation groove (3) is filled with a filling material (8).

8. The motor rotor according to claim 1, characterized in that: Two protrusions (9) are arranged on the side of the installation groove (3) close to the central axis, and the magnetic steel (2) is limited between the two protrusions (9).

9. A motor, comprising a motor rotor, characterized in that: The motor rotor is the motor rotor according to any one of claims 1 to 8.

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