Rotor core, rotor assembly and permanent magnet motor

Abstract

The invention provides a rotor core, a rotor assembly and a permanent magnet motor, the rotor core is formed by laminating rotor punching sheets, and each rotor punching sheet comprises a first outer tooth sheet and a structural member; the first outer tooth sheet is provided with a first assembly hole; the structural part comprises an inner circular ring, a plurality of second outer tooth pieces are distributed on the outer side of the inner circular ring in the circumferential direction, and the structural part at least comprises a second assembly hole formed in the second outer tooth pieces; the first outer tooth pieces and the second outer tooth pieces are distributed at intervals, and magnetic isolation gaps are formed between the first outer tooth pieces and the periphery of the inner circular ring. According to the invention, through rotary lamination of the rotor punching sheets and staggered arrangement of the magnetic isolation gaps of the adjacent permanent magnets, two magnetic flux output surfaces of the permanent magnets are arranged in the rotor iron core, and self-leakage flux of the rotor permanent magnets in the rotor iron core is effectively reduced, so that the size of external output magnetic flux of the rotor is improved, and the magnetic flux utilization rate of the rotor permanent magnets is improved.

Description

Technical Field

[0001] The present invention relates to the field of compressors, and in particular to a rotor core, a rotor assembly and a permanent magnet motor. Background Art

[0002] In order to reduce the use of rare metals in motor production, the motor industry has proposed the development prospect of motors with less or no heavy rare earths. Especially in the air-conditioning compressor industry, a large number of permanent magnets containing heavy rare earths are used and consumed every year. In order to reduce the dependence on heavy rare earths and at the same time not want the performance of the motor to be greatly reduced, ferrite permanent magnet motors will have a very large market application prospect.

[0003] At the same time, existing compressor motor rotors generally adopt an embedded permanent magnet structure, which causes the permanent magnets to form rotor self-leakage magnetism in the rotor magnetic steel slot reinforcement ribs or the magnetic isolation gap near the stator and rotor air gap (the reinforcement ribs and magnetic isolation gaps are both auxiliary components of the magnetic steel slots, generally at both ends of the magnets arranged in a straight line), affecting the utilization rate of the rotor permanent magnet output performance.

[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present invention, and therefore may include information that does not constitute the prior art known to those skilled in the art. Summary of the invention

[0005] In view of the problems in the prior art, the purpose of the present invention is to provide a rotor core, a rotor assembly and a permanent magnet motor, wherein the rotor core can effectively reduce the self-leakage magnetic flux of the rotor permanent magnet inside the rotor, thereby increasing the size of the magnetic flux output by the rotor assembly to the outside and improving the magnetic flux utilization rate of the rotor permanent magnet.

[0006] A first aspect of the present invention provides a rotor core, wherein the rotor core is formed by stacking rotor punchings, wherein the rotor punchings include a first outer tooth sheet and a structural member;

[0007] The first outer tooth plate is provided with a first assembly hole;

[0008] The structural member comprises an inner ring, and a plurality of second outer tooth plates distributed circumferentially on the outer side of the inner ring, and the structural member comprises at least one second assembly hole arranged on the second outer tooth plate;

[0009] The first outer tooth plate and the second outer tooth plate are spaced apart from each other, and a magnetic isolation gap is provided between the first outer tooth plate and the outer periphery of the inner ring.

[0010] According to the first aspect of the present invention, the number of the first outer tooth plates or the second outer tooth plates is N, where N is an integer and satisfies: 3≤N≤5.

[0011] According to the first aspect of the present invention, each of the second outer tooth plates is provided with a second assembly hole;

[0012] The first outer tooth plates and the second outer tooth plates of two adjacent layers of the rotor punching plates correspond to each other.

[0013] According to the first aspect of the present invention, the second outer tooth plate is a silicon steel plate.

[0014] According to a first aspect of the present invention, the first outer tooth plate and the second outer tooth plate are fan-shaped, and the first outer tooth plate and the second outer tooth plate are evenly arranged along the outer circumference of the inner ring, and the distance between the first outer tooth plate and the adjacent second outer tooth plate remains consistent along the radial direction of the rotor punching plate.

[0015] According to the first aspect of the present invention, the first outer tooth plate and / or the second outer tooth plate are fan-shaped; and

[0016] Both ends of the arc of the first outer tooth piece and / or the second outer tooth piece are provided with limiting members extending along the arc.

[0017] According to the first aspect of the present invention, a plurality of protrusion structures are provided on the outer circumference of the inner ring, and the protrusion structures are provided between adjacent first outer tooth plates and second outer tooth plates.

[0018] A second aspect of the present invention provides a rotor assembly, comprising the rotor core, an annular end plate, rivets and a plurality of permanent magnets;

[0019] The end plates are respectively arranged at the axial ends of the rotor core, and the end plates are provided with a plurality of third assembly holes. The rivets are axially penetrated through the first outer tooth plate, the second outer tooth plate and the end plates at both ends to fix the rotor punching sheets as a whole.

[0020] A third aspect of the present invention provides a permanent magnet motor, comprising the rotor assembly and the stator

[0021] According to a third aspect of the present invention, a plurality of protrusion structures are provided on the outer circumference of the inner ring, and the protrusion structures are provided between adjacent first outer tooth plates and second outer tooth plates;

[0022] The minimum distance between the rotor punching and the inner circumference of the stator is δ;

[0023] The distance between the adjacent first outer tooth plate and the second outer tooth plate is H M ;

[0024] The width and height of the protrusion structure are L and H respectively. 1 ;

[0025] The magnetic isolation gap is H 2, at least one of the following conditions is met:

[0026] (H M -L) / 2≥2δ;

[0027] H 1 ≥2δ;

[0028] L>2δ; or

[0029] H 2 ≥H 1 .

[0030] The present invention rotates and stacks rotor sheets, and the magnetic isolation gaps between adjacent permanent magnets are staggered so that the two magnetic flux output surfaces of the permanent magnets are inside the rotor core, effectively reducing the self-leakage magnetic flux of the rotor permanent magnets inside the rotor core, thereby increasing the size of the rotor's external output magnetic flux and improving the magnetic flux utilization rate of the rotor permanent magnets. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The drawings herein are incorporated into the specification and constitute a part of the specification, showing embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. By reading the detailed description of the non-limiting embodiments with reference to the following drawings, other features, purposes and advantages of the present invention will become more apparent. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings without creative work. In addition, the drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale. The same figure numbers in the figures represent the same or similar parts, and their repeated descriptions will be omitted. Some of the block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities.

[0032] Figure 1 It is a schematic structural diagram of a first outer tooth plate according to an embodiment of the present invention;

[0033] Figure 2 A schematic diagram of the structure of a structural member according to an embodiment of the present invention;

[0034] Figure 3 and Figure 4 They are respectively a three-dimensional view and a top view of a rotor punching sheet according to an embodiment of the present invention;

[0035] Figure 5 is a three-dimensional diagram of a rotor core according to an embodiment of the present invention;

[0036] Figure 6 A schematic structural diagram of an end plate according to an embodiment of the present invention;

[0037] Figure 7This is a schematic structural diagram of a rivet according to an embodiment of the present invention;

[0038] Figure 8 and Fig. 9 1 and 2 are respectively a structural schematic diagram and a top view of a rotor assembly according to an embodiment of the present invention; and 2.

[0039] Fig.10 FIG. 4 is a cross-sectional view of a permanent magnet motor according to an embodiment of the present invention. DETAILED DESCRIPTION

[0040] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that the disclosure will be more comprehensive and complete and to fully convey the concepts of the example embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0041] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" and the like mean that the specific features, structures, materials or characteristics represented in conjunction with the embodiment or example are included in at least one embodiment or example of this specification. Moreover, the specific features, structures, materials or characteristics represented may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples and features of different embodiments or examples represented in this specification without contradiction.

[0042] Throughout the specification, when it is said that a device is "connected" to another device, this includes not only the case of "direct connection" but also the case of "indirect connection" by placing other elements therebetween. Terms indicating relative spaces such as "front", "rear", "upper", and "lower" may be used to more easily explain the relationship of a device illustrated in the accompanying drawings relative to another device. Such terms refer not only to the meanings indicated in the accompanying drawings, but also to other meanings or operations of the device in use. For example, if the device in the accompanying drawings is turned over, a device that was described as being "under" other devices is described as being "over" other devices. Therefore, the exemplary term "under" includes both upper and lower sides. The device can be rotated 90° or other angles, and the terms representing relative spaces are interpreted accordingly.

[0043] Although the terms first, second, etc. are used to represent various elements in some examples, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, the first interface and the second interface, etc. are represented. Moreover, as used in this article, the singular forms "one", "one" and "the" are intended to also include plural forms, unless there is an opposite indication in the context. It should be further understood that the terms "comprising" and "including" indicate that there are the described features, steps, operations, elements, components, projects, kinds, and / or groups, but do not exclude the existence, occurrence or addition of one or more other features, steps, operations, elements, components, projects, kinds, and / or groups. The terms "or" and "and / or" used herein are interpreted as inclusive, or mean any one or any combination. Therefore, "A, B or C" or "A, B and / or C" means "any of the following: A; B; C; A and B; A and C; B and C; A, B and C". Only when the combination of elements, functions, steps or operations is inherently mutually exclusive in some way, will there be an exception to this definition.

[0044] Although not defined differently, all terms, including technical and scientific terms used herein, have the same meaning as those generally understood by those skilled in the art to which this specification belongs. Terms defined in commonly used dictionaries are additionally interpreted as having meanings consistent with the relevant technical literature and the contents of the current disclosure, and unless defined, shall not be overly interpreted as ideal or very formal meanings.

[0045] In view of the problems in the prior art, the present invention provides a rotor core, a rotor assembly and a permanent magnet motor, wherein the rotor core is formed by stacking rotor punchings, and the rotor punchings include a first outer tooth plate and a structural member; the structural member includes an inner ring and a plurality of second outer tooth plates distributed circumferentially on the outer side of the inner ring; the first outer tooth plate is provided with a first assembly hole; the structural member includes at least one second assembly hole provided on the second outer tooth plate; the first outer tooth plate and the second outer tooth plate are spaced apart, and a magnetic isolation gap is provided between the first outer tooth plate and the outer periphery of the inner ring. In the present invention, the magnetic isolation gaps of adjacent permanent magnets are staggered between layers through the rotational stacking of the rotor punchings, so that the two magnetic flux output surfaces of the permanent magnets are inside the rotor core, which effectively reduces the self-leakage magnetic flux of the rotor permanent magnets inside the rotor core, thereby increasing the size of the magnetic flux output to the outside of the rotor and improving the magnetic flux utilization rate of the rotor permanent magnets.

[0046] The structures of the rotor core, rotor assembly and permanent magnet motor of the present invention are further described below in conjunction with the accompanying drawings and specific embodiments. It can be understood that the various specific embodiments are not intended to limit the protection scope of the present invention.

[0047] The rotor core of the present invention is formed by stacking rotor punchings, wherein the rotor punchings include a first outer tooth plate 1 and a structural member 2. Figure 1 It is a schematic structural diagram of a first external tooth plate according to an embodiment of the present invention. Specifically, the first external tooth plate 1 is fan-shaped, and a first assembly hole 11 is provided in the first external tooth plate 1 . Figure 2 This is a schematic diagram of the structure of a structural member according to an embodiment of the present invention, wherein the structural member 2 comprises an inner ring 21, and a plurality of second outer tooth plates 22 circumferentially distributed on the outer side of the inner ring 21, and the structural member comprises at least one second assembly hole 221 provided on the second outer tooth plate 22. The first outer tooth plate 1 and the structural member 2 may be silicon steel plates, and the inner ring 21 and the second outer tooth plate 22 of the structural member 2 may be fixedly connected by gluing, or may be an integral member.

[0048] Figure 3 and Figure 4 They are respectively a stereoscopic view and a top view of a rotor punching sheet according to an embodiment of the present invention, wherein the first outer tooth sheet 1 and the second outer tooth sheet 22 are spaced apart, the first outer tooth sheet 1 and the second outer tooth sheet 22 can both be fan-shaped, and the two structures are similar. That is, in this embodiment, and the number of the first outer tooth sheet 1 and the second outer tooth sheet 22 is the same, the number N of the first outer tooth sheet or the second outer tooth sheet can be 3, 4 or 5. Figure 4 In the embodiment, the rotor punching includes four first outer tooth pieces 1 and four second outer tooth pieces 22, and the first outer tooth pieces 1 and the outer periphery of the inner ring 21 are provided with magnetic isolation gaps S. In some other embodiments, the number of first outer tooth pieces 1 and second outer tooth pieces 22 may be different, such as two second outer tooth pieces 22 are relatively provided on the structural member 2, and the remaining six outer pieces are first outer tooth pieces. In this case, the number of magnetic isolation gaps S of a single rotor punching is also 6. The following will describe the first outer tooth piece 1 separated from the structural member, assembled through end plates and rivets into a rotor assembly suitable for a permanent magnet motor.

[0049] The first outer tooth piece 1 and the second outer tooth piece 22 are fan-shaped, and the first outer tooth piece 1 and the second outer tooth piece 22 are evenly arranged along the outer circumference of the inner ring 21, and the distance between the first outer tooth piece 1 and the adjacent second outer tooth piece 22 is consistent along the radial direction of the rotor punching. Figure 4 As shown, the distance between the first outer tooth plate and the adjacent second outer tooth plate 22 is H M .

[0050] Since the rotor core is made of multiple rotor stampings, Figure 5 is a three-dimensional diagram of a rotor core according to an embodiment of the present invention. In this embodiment, the rotor core is composed of two Figure 3The rotor punchings of the embodiment are stacked, and when stacked, the two rotor punchings have a relative rotation angle, so that the first outer tooth plate 1 and the second outer tooth plate 22 of the two adjacent layers of the rotor punchings correspond to each other. In the embodiment where the rotor punchings include eight outer tooth plates, the relative rotation angle is 45° (360° / 8). The rotor cores of different embodiments, such as the first outer tooth plate 1 and the second outer tooth plate 22 of the adjacent layers correspond to each other, and the rotation angle is 360° / M, where M is the number of outer tooth plates, that is, the sum of the number of the first outer tooth plate 1 and the second outer tooth plate 22. At this time, each of the second outer tooth plates 22 needs to be provided with a second assembly hole 221 to facilitate the rivet connection. Of course, multiple rotor punchings can also be directly stacked to obtain the rotor core. At this time, the first outer tooth plate 1 of the two adjacent layers of rotor punchings is stacked with the first outer tooth plate 1, and the second outer tooth plate 22 is stacked with the second outer tooth plate 22. The number of rotor punchings included in the rotor core is not limited to two, which will not be repeated here.

[0051] The rotor assembly includes a rotor core, an annular end plate 4, a rivet 5 and a plurality of permanent magnets; the end plate 4 includes an annular body 41 and a plurality of third assembly holes 42 arranged on the annular body 41, Figure 6 The end plate 4 is made of an integral non-magnetic material. The rivet 5 includes a rod 51 and riveted portions 52 located at both ends of the rod 51. Figure 7 The end plates 4 are respectively arranged at the axial ends of the rotor core, and the rivets 5 are axially penetrated through the first outer tooth plate 1, the second outer tooth plate 22 and the end plates 4 at both ends to fix the rotor punchings as a whole. Figure 8 and Fig. 9 As shown, therefore, the position and number of the third assembly hole 42 are adapted to the number of the first assembly hole 11 / second assembly hole 221 of the rotor punching. It should be noted that when the first outer tooth sheet 1 and the second outer tooth sheet 22 of two adjacent layers of the rotor punching correspond to each other, the second outer tooth sheet 22 needs to be provided with a second assembly hole 221 at the adapted position. The end plate and the rivet can play a role in stabilizing the connection of the various components of the rotor assembly, so that when the rotor core rotates at high speed, it can still maintain a good structural state, ensure that the compressor using the permanent magnet motor has a stable and large amount of cooling output, and improve the working stability of the permanent magnet motor.

[0052] In order to install the permanent magnet between adjacent external tooth pieces, the first external tooth piece 1 / the second external tooth piece 22 is fan-shaped; both ends of the arc of the first external tooth piece 1 / the second external tooth piece 22 are provided with limit pieces extending along the arc, the first external tooth piece 1 is the first limit piece 12, and the second external tooth piece 22 is the second limit piece 222, and the limit piece plays a fixing role on the permanent magnet when the permanent magnet is installed between the two external tooth pieces. In some other embodiments, the outer periphery of the inner ring can also be provided with a plurality of raised structures 211, and the raised structures 211 are arranged between the adjacent first external tooth pieces and the second external tooth pieces, that is, the number of raised structures 211 is equivalent to the total number of the first external tooth pieces and the second external tooth pieces of the rotor punching. The raised structure 211 can support and stabilize the permanent magnet and improve the structural stability of the rotor assembly when it rotates at high speed.

[0053] The present invention also provides a permanent magnet motor, comprising the rotor assembly and a stator 9, Fig.10 : is a cross-sectional view of a permanent magnet motor according to an embodiment of the present invention. The minimum distance between the rotor punching and the inner periphery of the stator 9 is δ, and the width and height of the protrusion structure are L and H respectively. 1 (See Figure 2 ), the distance between the adjacent first outer tooth plate and the second outer tooth plate is H M , the magnetic isolation gap S is H 2 (See Figure 4 ), in order to effectively reduce the self-leakage magnetic flux of the rotor permanent magnet inside the rotor core, thereby increasing the size of the rotor's external output magnetic flux and improving the magnetic flux utilization rate of the rotor permanent magnet, according to empirical values, at least one of the following conditions is met: (H M -L) / 2≥2δ; H 1 ≥2δ; L>2δ; H 2 ≥H 1 .

[0054] The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, it is obvious that the present application is not limited to the details of the above exemplary embodiments, and the present application can be implemented in other specific forms without departing from the spirit or basic features of the present application. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive, and the scope of the present application is limited by the attached claims rather than the above description, so it is intended to include all changes within the meaning and scope of the equivalent elements of the claims in the present application. Any figure mark in the claims should not be regarded as limiting the claims involved.

Claims

1. A rotor core, characterized in that: The rotor core is formed by stacking rotor sheets, and the rotor sheets include a first outer tooth sheet and a structural member; The first outer tooth plate is provided with a first assembly hole; The structural member comprises an inner ring, and a plurality of second outer tooth plates distributed circumferentially on the outer side of the inner ring, and the structural member comprises at least one second assembly hole arranged on the second outer tooth plate; The first outer tooth plate and the second outer tooth plate are spaced apart from each other, and a magnetic isolation gap is provided between the first outer tooth plate and the outer periphery of the inner ring.

2. The rotor core according to claim 1, characterized in that: The number of the first outer tooth plates or the second outer tooth plates is N, where N is an integer and satisfies: 3≤N≤5.

3. The rotor core according to claim 1, characterized in that: Each of the second outer tooth plates is provided with a second assembly hole; The first outer tooth plates and the second outer tooth plates of two adjacent layers of the rotor punching plates correspond to each other.

4. The rotor core according to claim 1, characterized in that: The second outer tooth plate is a silicon steel plate.

5. The rotor core according to claim 4, characterized in that: The first outer tooth plate and the second outer tooth plate are fan-shaped, and are evenly arranged along the outer circumference of the inner ring. The distance between the first outer tooth plate and the adjacent second outer tooth plate remains consistent along the radial direction of the rotor punching plate.

6. The rotor core according to claim 1, characterized in that: The first outer tooth piece and / or the second outer tooth piece are fan-shaped; and Both ends of the arc of the first outer tooth piece and / or the second outer tooth piece are provided with limiting members extending along the arc.

7. The rotor core according to claim 1, characterized in that: A plurality of protrusion structures are arranged on the outer circumference of the inner ring, and the protrusion structures are arranged between the adjacent first outer tooth plates and the second outer tooth plates.

8. A rotor assembly, characterized in that: The rotor core according to claim 1, an annular end plate, rivets and a plurality of permanent magnets; The end plates are respectively arranged at the axial ends of the rotor core, and the end plates are provided with a plurality of third assembly holes. The rivets are axially penetrated through the first outer tooth plate, the second outer tooth plate and the end plates at both ends to fix the rotor punchings as a whole.

9. A permanent magnet motor, characterized in that: It comprises the rotor assembly and the stator as claimed in claim 8.

10. The permanent magnet motor according to claim 9, characterized in that: The outer circumference of the inner ring is provided with a plurality of protrusion structures, and the protrusion structures are provided between the adjacent first outer tooth pieces and the second outer tooth pieces; The minimum distance between the rotor punching and the inner circumference of the stator is δ; The distance between the adjacent first outer tooth plate and the second outer tooth plate is H M ; The width and height of the protruding structure are L and H1 respectively; The magnetic isolation gap is H2, which satisfies at least one of the following conditions: (H M -L) / 2≥2δ; H1≥2δ; L>2δ; or H2≥H1.

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