Rotor iron core, rotor assembly and motor using rotor iron core and rotor assembly

Abstract

The invention discloses a rotor core, a rotor assembly and a motor using the same, and the rotor core comprises a central part and a plurality of magnet yoke parts which are distributed at intervals along the circumferential direction and are arranged around the central part. A plurality of supporting core columns are formed on the central part at intervals in the circumferential direction, and the supporting core columns of the central part and the magnet yoke parts are arranged in a staggered mode. At least one supporting core column for the central part, wherein a magnetic bridge is formed at the end part of the supporting core column; two sides of at least one magnet yoke part are respectively connected with the magnetic bridges at the two adjacent supporting core columns; and a permanent magnet slot is formed between at least one pair of adjacent magnet yoke parts, so that the permanent magnet can be inserted into the slot to form a magnetic pole. The connecting structure of the magnetic yoke part and the central part is higher in mechanical strength, the two magnetic bridges form a push-pull linkage supporting structure, the severe working conditions such as frequent starting, heavy load torque output, rapid acceleration and rapid deceleration of the motor can be met, and the motor has the advantages of being reasonable in structure, low in magnetic leakage, small in material consumption of the rotor iron core, easy to manufacture and machine and high in mechanical strength.

Description

Technical Field

[0001] The present invention relates to the technical field of motor rotor structures, and in particular to a rotor core, a rotor assembly and a motor using the same. Background Art

[0002] A motor is an electromechanical device that can convert electrical energy into mechanical energy. There are many types and uses of motors, among which brushless motors are an important type of motor.

[0003] The rotor assembly is one of the core components of the motor, among which the permanent magnet rotor assembly is widely used in brushless motors; the Chinese utility model announcement text with announcement number CN216056537U and name "Rotor Core and Motor Rotor" discloses a typical permanent magnet rotor assembly structure.

[0004] In order to improve efficiency and reduce the use of rotor core materials, the permanent magnet rotor assembly in the prior art usually adopts a V-shaped structure, a U-shaped structure or a multiple magnet structure. In addition, there is also a spoke-shaped low-cost solution. For example, the above-mentioned Chinese utility model announcement text records: See Figure 1-2 ,in Figure 1 FIG. 1 is an overall view of a rotor assembly using the rotor core proposed in the present disclosure. Figure 2 It is a cross-sectional view of a specific embodiment of the rotor core proposed in the present disclosure. The rotor assembly may include: an injection molding body 14, a rotor core, a permanent magnet 12, and a rotor shaft 13. The permanent magnet 12 is embedded in the permanent magnet mounting groove 8 of the rotor core. The injection molding body 14 encapsulates the rotor core and the permanent magnet 12 together, and the rotor shaft 13 is located in the central axis hole 11 of the rotor core. The rotor core includes a plurality of punching sheets, each of which has a base 10 formed with a central axis hole, and a plurality of triangular teeth 20 arranged circumferentially around the base. Among them, each triangular tooth 20 includes an outer edge 21 away from the base 10 and a tip 22 close to the base 10. The punching sheet is, for example, a silicon steel sheet... According to a preferred embodiment, among all the triangular teeth of the end punching sheet, at least one pair of triangular teeth opposite to each other have their tips connected to the base 10 through an internal magnetic bridge 6.

[0005] However, in order to reduce the leakage magnetic flux of the magnetic resistance part (i.e., the above-mentioned internal magnetic bridge 6), the permanent magnet rotor assembly of the above-mentioned structure will set the mechanical structure of the magnetic resistance part to be very weak. Under the conditions of frequent motor starting, heavy-load torque output, rapid acceleration and rapid deceleration, the mechanical strength of the rotor core is insufficient and deformation and breakage are prone to occur.

[0006] In summary, how to provide the motor with a rotor core that has a reasonable structure, low magnetic leakage, low rotor core material consumption, easy manufacturing and processing, and high mechanical strength has become an urgent problem to be solved. Summary of the invention

[0007] The object of the present invention is to provide a rotor core, a rotor assembly and a motor using the same, which have the characteristics of reasonable structure, low magnetic leakage, low rotor core material consumption, easy manufacturing and processing, and high mechanical strength.

[0008] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a rotor core, comprising a central part and a plurality of yoke parts, wherein the yoke parts are spaced apart in the circumferential direction and arranged around the central part; the central part is formed with a plurality of supporting core columns spaced apart in the circumferential direction, and the supporting core columns of the central part and the yoke parts are staggered with each other; a magnetic bridge is formed at the end of at least one supporting core column of the central part; at least one of the yoke parts has its two sides respectively connected to the magnetic bridges at two adjacent supporting core columns; a permanent magnet slot is formed between at least one pair of adjacent yoke parts for the permanent magnet to be inserted therein to form a magnetic pole.

[0009] In the above technical solution, for each supporting core column of the central part, magnetic bridges are formed on both sides of its end; for each yoke part, its two sides are respectively connected to the magnetic bridges at the two adjacent supporting core columns; a permanent magnet slot is formed between each pair of adjacent yoke parts for the permanent magnet to be inserted therein to form a magnetic pole.

[0010] In the above technical solution, a first avoidance position is formed between at least one pair of adjacent support core columns; and the first avoidance position at least extends to a position that crosses the magnetic bridge.

[0011] In the above technical solution, a first avoidance position is formed between each pair of adjacent supporting core columns.

[0012] In the above technical solution, one side of the first avoidance position extends toward the yoke portion to form an arched surface.

[0013] In the above technical solution, at least one of the yoke parts has a second space therein.

[0014] In the above technical solution, the width of the permanent magnet slot is W1, and the width of the magnetic bridge adjacent to the permanent magnet slot is W2; then W2: W1≤1 / 3.

[0015] A rotor assembly comprises the above-mentioned rotor core.

[0016] In the above technical solution, the rotor assembly of the present invention further includes a plurality of permanent magnets; the permanent magnets are correspondingly inserted into the permanent magnet slots of the rotor core to form magnetic poles.

[0017] A motor comprises the above-mentioned rotor assembly.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: the rotor core, rotor assembly and motor using the same of the present invention, the two sides of the yoke part are respectively connected to the magnetic bridges at the two adjacent supporting core columns, in this way, the yoke part is supported on the outer periphery of the center part through the supporting core columns and the corresponding two magnetic bridges; compared with the rotor core in the prior art, the connection structure between the yoke part and the center part of the present invention has higher mechanical strength, is not prone to deformation and breakage, and has higher stability and is not prone to shaking; when the motor is running, one section of the magnetic bridge pulls the yoke part, and the other section of the magnetic bridge pushes the yoke part, and the two sections of the magnetic bridge form a push-pull linkage support structure, which can meet the severe working conditions such as frequent motor starting, heavy-load torque output, rapid acceleration and rapid deceleration; in summary, the rotor core, rotor assembly and motor using the same of the present invention have the characteristics of reasonable structure, low magnetic leakage, low rotor core material consumption, easy manufacturing and processing, and high mechanical strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is one of the structural views of the rotor core in the present invention.

[0020] Figure 2 This is the second structural view of the rotor core in the present invention.

[0021] Figure 3 It is a structural view of the rotor assembly in the present invention.

[0022] Figure 4 This is a magnetic field simulation test diagram of the present invention.

[0023] The accompanying drawings are marked as follows: 1. rotor core; 11. center part; 12. yoke part; 13. supporting core column; 14. magnetic bridge; 15. permanent magnet slot; 16. first avoidance position; 161. arched surface; 17. second avoidance position; 2. permanent magnet. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] This embodiment provides a rotor core that can be used in an electric motor and is used as a mechanical structure support base component and a magnetic conductive component of a rotor assembly.

[0026] The rotor core 1 has good magnetic conductivity, and can be a metal body formed by stacking a number of silicon steel sheets, or can be a solid metal body formed by integral die-casting or machining.

[0027] See also Figure 1 and Figure 2 The rotor core 1 of this embodiment includes a central portion 11 and a plurality of yoke portions 12, wherein the central portion 11 is roughly annular in structure, and the yoke portions 12 are roughly petal-shaped in structure; the yoke portions 12 are spaced apart along the circumferential direction and arranged around the central portion 11. In this embodiment, the yoke portions 12 are evenly distributed along the circumferential direction, and 8 yoke portions are arranged.

[0028] In order to provide a reliable mechanical connection structure for the center portion 11 and the yoke portion 12 and reduce magnetic leakage of the mechanical connection structure, the rotor core 1 of this embodiment is configured as follows:

[0029] The central portion 11 is provided with a plurality of support core columns 13 spaced apart in the circumferential direction, and the support core columns 13 of the central portion 11 and the yoke portion 12 are staggered with each other, that is, a support core column 13 is provided between each pair of adjacent yoke portions 12 of the central portion 11 .

[0030] At least one supporting stem 13 of the central part 11 has a magnetic bridge 14 formed at its end.

[0031] For at least one yoke portion 12 , two sides thereof are respectively connected to the magnetic bridges 14 at two adjacent supporting core columns 13 .

[0032] A permanent magnet slot 15 is formed between at least one pair of adjacent yoke parts 12 for the permanent magnet 2 to be inserted therein to form a magnetic pole.

[0033] In this embodiment, for each supporting core column 13 of the central portion 11, magnetic bridges 14 are formed on both sides of its end; for each yoke portion 12, its two sides are respectively connected to the magnetic bridges 14 at two adjacent supporting core columns 13; a permanent magnet slot 15 is formed between each pair of adjacent yoke portions 12 for the permanent magnet 2 to be inserted therein to form a magnetic pole.

[0034] It can be understood that the central portion 11, the yoke portion 12, the supporting core column 13 and the magnetic bridge 14 of the rotor core 1 are all integrally formed structural features, and the central portion 11, the yoke portion 12, the supporting core column 13 and the magnetic bridge 14 can be obtained by punching, machining or integral die-casting, and the permanent magnet slot 15 is a groove-shaped structure naturally obtained after the various structural features of the rotor core 1 are formed; in this way, each yoke portion 12 can be supported on the outer periphery of the central portion 11 through the supporting core column 13 and the corresponding two-section magnetic bridge 14.

[0035] Furthermore, a first avoidance position 16 is formed between at least one pair of adjacent supporting core columns 13, and the first avoidance position 16 extends at least to a position crossing the magnetic bridge 14. Specifically, one side of the first avoidance position 16 extends in the direction of the yoke portion 12 and at least extends to a position crossing the magnetic bridge 14. In the present embodiment, a first avoidance position 16 is formed between each pair of adjacent supporting core columns 13. In fact, the first avoidance position 16 is a groove-shaped structure integrally formed at the rotor core 1, which can be obtained by punching, machining or integral die-casting.

[0036] Furthermore, one side of the first avoidance position 16 extends toward the yoke portion 12 to form an arched surface 161 , that is, one side of the first avoidance position 16 close to the yoke portion 12 is configured as the arched surface 161 .

[0037] Furthermore, for at least one yoke portion 12, a second air avoidance space 17 is formed therein. In the present embodiment, the cross-section of the second air avoidance space 17 is in the shape of an elongated strip and is located in the center of the yoke portion 12 to separate the yoke portion 12 into two halves. In fact, the second air avoidance space 17 is a groove-shaped structure integrally formed in the rotor core 1, which can be obtained by punching, machining or integral die-casting.

[0038] It can be understood that the first avoidance space 16 and the second avoidance space 17 both play the role of "air gap" during the magnetic field guidance process.

[0039] Furthermore, the width of the permanent magnet slot 15 is W1, and the width of the magnetic bridge 14 adjacent to the permanent magnet slot 15 is W2, then W2: W1≤1 / 3; the width W2 of the magnetic bridge 14 is set at this ratio. Compared with the single magnetic bridge in the prior art, the width W2 of the magnetic bridge 14 in this embodiment can be greatly reduced, but higher mechanical strength can be obtained to ensure a safe structure for high-speed operation. Therefore, while meeting the mechanical strength requirements, the rotor assembly effectively reduces the magnetic leakage phenomenon at the magnetic bridge 14, thereby improving the motor efficiency.

[0040] See also Figure 3 This embodiment also provides a rotor assembly, which includes the above-mentioned rotor core 1.

[0041] The rotor assembly of the present embodiment also includes a plurality of permanent magnets 2, wherein the permanent magnets 2 are made of neodymium iron boron or ferrite and have permanent magnetism; in the present embodiment, the permanent magnets 2 are square sheet structures (also called "magnetic tiles"), and their magnetic poles are located on the two faces with the largest surface areas, and a magnetic field can be generated outward from the two faces; the permanent magnets 2 are correspondingly inserted into the permanent magnet slots 15 of the rotor core 1 to form magnetic poles. In the present embodiment, four permanent magnets 2 are respectively inserted in a stacked manner into each permanent magnet slot 15 of the rotor core 1.

[0042] It is understandable that after the permanent magnets 2 are correspondingly inserted into the permanent magnet slots 15 of the rotor core 1, the rotor assembly can be placed in an injection mold as a whole to encapsulate the rotor assembly and fix the rotor core 1 and the permanent magnets 2 as a whole.

[0043] This embodiment also provides a motor, which includes the above-mentioned rotor assembly.

[0044] See also Figure 4 , from the perspective of magnetic permeability characteristics, we can know that:

[0045] 1. Since the width of the supporting core column 13 and the magnetic bridge 14 is small, when the magnetic field generated by the permanent magnet 2 passes through the supporting core column 13 and the magnetic bridge 14, the supporting core column 13 and the magnetic bridge 14 will be magnetically saturated, making it difficult for more magnetic fields to pass through, thereby reducing the magnetic leakage phenomenon of the magnetic field at the supporting core column 13 and the magnetic bridge 14. Most of the magnetic field is introduced into the yoke part 12 and participates in the output process of the motor, effectively improving the efficiency of the motor.

[0046] 2. A first avoidance position 16 is provided at the rotor core 1 to produce a magnetic field concentration effect. Specifically, the magnetic field generated by the permanent magnet 2 produces a salient pole effect through the guidance of the first avoidance position 16, so that the magnetic field is further introduced into the yoke part 12 and participates in the output process of the motor, thereby further improving the efficiency of the motor.

[0047] 3. An arched surface 161 is provided at the first avoidance position 16 so that the center of the yoke portion 12 obtains a higher magnetic field strength, which can simulate a sinusoidal magnetic field, thereby increasing the positive limit of the rotor assembly and optimizing the electromagnetic noise of the motor.

[0048] 4. A second air gap 17 is provided at the rotor core 1 to provide an "air gap" between two adjacent permanent magnets 2 to avoid mutual interference of the magnetic fields generated by the two adjacent permanent magnets 2.

[0049] In addition, a first avoidance position 16 is provided at the rotor core 1, and an air flow channel can be formed inside the rotor core 1 (the air flow can pass through the rotor core 1 along the first avoidance position 16), thereby increasing the heat exchange area between the air flow and the rotor core 1, so as to improve the heat dissipation performance of the rotor assembly.

[0050] However, the technical effects of the rotor core, rotor assembly and motor using the same in this embodiment are not limited to the above contents. More importantly, the following are some of the technical effects of the rotor core, rotor assembly and motor using the same in this embodiment:

[0051] The two sides of the yoke part 12 are respectively connected to the magnetic bridges 14 at the two adjacent supporting core columns 13. In this way, the yoke part 12 is supported on the outer periphery of the center part 11 through the supporting core columns 13 and the corresponding two magnetic bridges 14. Compared with the rotor core 1 in the prior art, the connection structure between the yoke part 12 and the center part 11 of this embodiment has higher mechanical strength, is not prone to deformation and breakage, and has higher stability and is not prone to shaking. When the motor is running, one section of the magnetic bridge 14 pulls the yoke part 12, and the other section of the magnetic bridge 14 pushes the yoke part 12. The two sections of the magnetic bridge 14 form a push-pull linkage support structure, which can meet the severe working conditions such as frequent motor starting, heavy-load torque output, rapid acceleration and rapid deceleration. In summary, the rotor core 1, the rotor assembly and the motor using the same of this embodiment have the characteristics of reasonable structure, low magnetic leakage, low material consumption of the rotor core 1, easy manufacturing and processing, and high mechanical strength.

[0052] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A rotor core, comprising a central portion and a plurality of yoke portions, wherein the yoke portions are spaced apart in a circumferential direction and arranged around the central portion; It is characterized in that The central part is formed with a plurality of support core columns at intervals along the circumferential direction, and the support core columns of the central part and the magnetic yoke part are arranged in a staggered manner; At least one supporting core leg of the central portion has a magnetic bridge formed at its end; For at least one of the yoke parts, two sides thereof are respectively connected to the magnetic bridges at two adjacent supporting core columns; A permanent magnet slot is formed between at least one pair of adjacent yoke parts for inserting a permanent magnet therein to form a magnetic pole.

2. The rotor core according to claim 1, characterized in that: For each supporting core column of the central part, magnetic bridges are formed on both sides of its end portion; For each of the magnetic yoke parts, two sides thereof are respectively connected to the magnetic bridges at two adjacent supporting core columns; A permanent magnet slot is formed between each pair of adjacent yoke parts for inserting a permanent magnet therein to form a magnetic pole.

3. The rotor core according to claim 1 or 2, characterized in that: A first avoidance position is formed between at least one pair of adjacent support core columns; Furthermore, the first clearance position at least extends to a position beyond the magnetic bridge.

4. The rotor core according to claim 3, characterized in that: A first avoidance position is formed between each pair of adjacent supporting core columns.

5. The rotor core according to claim 3, characterized in that: One side of the first avoidance position extends toward the yoke portion to form an arched surface.

6. The rotor core according to claim 1, characterized in that: At least one of the yoke parts has a second escape space formed therein.

7. The rotor core according to claim 1, characterized in that: The width of the permanent magnet slot is W1, and the width of the magnetic bridge adjacent to the permanent magnet slot is W2; Then W2:W1≤1 / 3.

8. A rotor assembly, characterized in that: It comprises the rotor core described in any one of claims 1-7.

9. The rotor assembly according to claim 8, characterized in that Also included are a number of permanent magnets; The permanent magnets are correspondingly inserted into the permanent magnet slots of the rotor core to form magnetic poles.

10. A motor, characterized in that: Comprising the rotor assembly according to claim 8 or 9.

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