Magnetic bearing assembly, outer rotor motor assembly and motor

Abstract

The present invention provides a magnetic suspension bearing assembly, an outer rotor motor assembly and a motor, which relate to the technical field of motors and solve the technical problem that the existing magnetic suspension motors are large in size at least in the axial direction and are not suitable for occasions with narrow space and large inertia. The magnetic suspension bearing assembly includes a central axis assembly and a rotor assembly; wherein the central axis assembly has a accommodating gap, at least part of the section of the rotor assembly is arranged in the gap, and the central axis assembly can provide electromagnetic force to the rotor assembly to keep the rotor assembly suspended and at least limit the displacement of the rotor assembly in its axial and radial directions. The outer rotor motor assembly includes a motor stator assembly and a magnetic suspension bearing assembly. The motor includes a motor body and an outer rotor motor assembly. The present invention is used to provide a magnetic suspension bearing assembly, an outer rotor motor assembly and a motor that are compact in structure and can reduce the size of the entire motor while ensuring the moment of inertia.

Description

Technical Field

[0001] The present invention relates to the technical field of motors, and in particular to a magnetic bearing assembly, an outer rotor motor assembly provided with the magnetic bearing assembly, and a motor provided with the outer rotor motor assembly. Background Art

[0002] Magnetic bearings are low-loss, high-performance bearings that suspend the shaft (also called the rotor) in the motor through the electromagnetic force of the magnetic bearings, so that there is no mechanical contact and no mechanical friction between the shaft and the bearing. While achieving high speed of the motor rotor, it also has the advantages of no mechanical wear, low energy consumption, low noise, long life, no need for lubrication and sealing, and no oil pollution. The speed of the magnetic suspension motor rotor is only limited by the tensile strength of the rotor material. Therefore, the circumferential speed of the magnetic suspension motor rotor can be very high, and its application in high-speed equipment is becoming more and more extensive.

[0003] The outer rotor motor is opposite to the general motor, with the rotor on the outside and the stator on the inside. Its advantages are large moment of inertia, good heat dissipation, saving copper wire, and loads such as fan blades can be directly connected to the rotor, meeting the installation requirements of a small-volume whole machine with a certain power. The diameter of the armature core can be made larger, thereby improving the efficiency and output power of the motor under unstable loads. However, the applicant has found that the magnetic levitation motor in the prior art is generally equipped with at least two radial magnetic bearings and a pair of axial magnetic bearings to position the rotor radially and axially, plus the motor stator and rotor, resulting in a larger size of the whole machine at least in the axial direction. Summary of the invention

[0004] The object of the present invention is to provide a magnetic suspension bearing assembly, an outer rotor motor assembly provided with the magnetic suspension bearing assembly, and a motor provided with the outer rotor motor assembly, so as to solve the technical problem that the magnetic suspension motor in the prior art is large in size at least in the axial direction and is not suitable for occasions with narrow space and large inertia. The various technical effects that can be produced by the preferred technical solution among the various technical solutions of the present invention are described in detail below.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] The magnetic bearing assembly provided by the present invention comprises a central shaft assembly and a rotor assembly; wherein:

[0007] The central shaft component has an accommodating gap, in which at least a portion of the rotor component is disposed. The central shaft component can provide electromagnetic force to the rotor component to keep the rotor component suspended and at least limit the axial and radial displacements of the rotor component.

[0008] In a preferred or optional embodiment, the rotor assembly includes a rotor and a thrust plate, the thrust plate is fixedly connected to the rotor, the rotor is sleeved outside at least a portion of the central shaft assembly, and at least a portion of the thrust plate is arranged in a gap within the central shaft assembly.

[0009] In a preferred or optional embodiment, the central axis assembly includes an axial positioning assembly and a radial positioning assembly, the thrust plate includes an axial positioning portion and a radial positioning portion, the axial positioning portion is arranged in a gap in the axial positioning assembly, and the radial positioning portion is arranged in a gap between the axial positioning assembly and the radial positioning assembly.

[0010] In a preferred or optional embodiment, the central axis assembly also includes a mounting shaft, the axial positioning assembly includes a first axial iron core and a second axial iron core, the first axial iron core and the second axial iron core are both sleeved and fixedly mounted on the mounting shaft and the two are arranged at an axial interval along the mounting shaft, and the axial positioning portion of the thrust plate is arranged in the gap between the first axial iron core and the second axial iron core.

[0011] In a preferred or optional embodiment, an axial winding is wound around the first axial iron core and the second axial iron core in an area close to the axial positioning portion to provide an axial electromagnetic force to the rotor assembly.

[0012] In a preferred or optional embodiment, the axial windings arranged in the first axial core and the second axial core are both wound along the circumference of the installation shaft.

[0013] In a preferred or optional embodiment, the central axis assembly also includes a mounting shaft, the axial positioning assembly is fixedly mounted on the mounting shaft, the radial positioning assembly includes a radial iron core, the radial iron core is sleeved and fixed on the mounting shaft and there is a gap between the radial iron core and the axial positioning assembly along the radial direction of the mounting shaft, and the radial positioning portion of the thrust plate is arranged in the gap between the radial iron core and the axial positioning assembly.

[0014] In a preferred or optional embodiment, a radial winding is wound inside the radial core to provide radial electromagnetic force to the rotor assembly.

[0015] In a preferred or optional embodiment, the radial winding disposed in the radial core is wound along the axial direction of the mounting shaft.

[0016] In a preferred or optional embodiment, the central axis assembly further includes a mounting axis and a housing, and the mounting axis is fixedly connected to the housing.

[0017] The outer rotor motor assembly provided by the present invention comprises a motor stator assembly and a magnetic bearing assembly provided by any technical solution of the present invention; wherein:

[0018] The motor stator assembly is fixedly connected to the central shaft assembly, and the rotor assembly comprises a rotor and a thrust plate. The thrust plate is fixedly connected to the rotor, and the rotor is sleeved outside the motor stator assembly.

[0019] In a preferred or optional embodiment, the motor stator assembly includes a stator core and a stator winding, the stator core is fixedly connected to the central axis assembly, and the stator winding is wound in the stator core along the axial direction of the central axis assembly.

[0020] The motor provided by the present invention comprises a motor body and an outer rotor motor assembly provided by any technical solution of the present invention.

[0021] Based on the above technical solution, the embodiments of the present invention can at least produce the following technical effects:

[0022] The magnetic suspension bearing assembly provided by the present invention comprises a central axis assembly and a rotor assembly, wherein at least a part of the section of the rotor assembly is arranged in a gap in the central axis assembly. Since the central axis assembly can provide electromagnetic force to the rotor assembly to keep the rotor assembly suspended, it can be ensured that the rotor assembly has no mechanical wear during rotation, has low energy consumption, and has low noise; the electromagnetic force provided by the central axis assembly to the rotor assembly can also limit the axial and radial displacements of the rotor assembly, and at least two radial magnetic bearings and a pair of axial magnetic bearings in the prior art are integrated into one magnetic suspension bearing assembly. While ensuring the required inertia, the size in at least the axial direction is greatly saved, and the structure is more compact, so that it can be more conveniently applied to motors with narrow space but requiring large inertia. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 A schematic diagram of the axial cross-sectional structure of an outer rotor motor assembly provided by the present invention;

[0025] Figure 2 A schematic diagram of the cross-sectional structure of an outer rotor motor assembly provided by the present invention;

[0026] Figure 3 for Figure 2The schematic diagram of the electromagnetic circuit of the motor and the electromagnetic circuit of the radial positioning component shown;

[0027] Figure 4 for Figure 3 A partial enlarged schematic diagram of

[0028] Figure 5 for Figure 2 The schematic diagram of the electromagnetic circuit of the axial positioning component is shown.

[0029] In the figure, 1. central axis assembly; 11. axial positioning assembly; 111. first axial core; 112. second axial core; 113. axial winding; 12. radial positioning assembly; 121. radial core; 122. radial winding; 13. mounting shaft; 14. housing; 15. axial air gap; 16. radial air gap; 2. rotor assembly; 21. rotor; 22. thrust plate; 221. axial positioning portion; 222. radial positioning portion; 3. motor stator assembly; 31. stator core; 32. stator winding; 4. motor air gap. DETAILED DESCRIPTION

[0030] To make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0031] The present invention provides a magnetic suspension bearing assembly which has a compact structure and can reduce the axial size of the entire motor while ensuring the moment of inertia, an outer rotor motor assembly provided with the magnetic suspension bearing assembly, and a motor provided with the outer rotor motor assembly.

[0032] Combine the following Figure 1 to Figure 5 The technical solution provided by the present invention is described in more detail.

[0033] like Figure 1 to Figure 5 As shown, the magnetic bearing assembly provided by the present invention comprises a central shaft assembly 1 and a rotor assembly 2; wherein,

[0034] The central shaft assembly 1 has an accommodating gap, in which at least a portion of the rotor assembly 2 is disposed. The central shaft assembly 1 can provide electromagnetic force to the rotor assembly 2 to keep the rotor assembly 2 suspended and at least limit the axial and radial displacements of the rotor assembly 2.

[0035] The magnetic suspension bearing assembly provided by the present invention comprises a central axis assembly 1 and a rotor assembly 2, wherein at least a portion of the rotor assembly 2 is arranged in a gap in the central axis assembly 1. Since the central axis assembly 1 can provide electromagnetic force to the rotor assembly 2 to keep the rotor assembly 2 suspended, it can be ensured that the rotor assembly 2 has no mechanical wear during rotation, has low energy consumption, and has low noise; the electromagnetic force provided by the central axis assembly 1 to the rotor assembly 2 can also limit the axial and radial displacements of the rotor assembly 2, and integrates at least two radial magnetic bearings and a pair of axial magnetic bearings in the prior art into one magnetic suspension bearing assembly. While ensuring the required inertia, the size in at least the axial direction is greatly saved, and the structure is more compact, so that it can be more conveniently applied to motors with narrow space but requiring large inertia.

[0036] As a preferred or optional embodiment, the rotor assembly 2 includes a rotor 21 and a thrust plate 22, the thrust plate 22 is fixedly connected to the rotor 21, the rotor 21 is sleeved outside at least a portion of the central shaft assembly 1, and at least a portion of the thrust plate 22 is arranged in the gap inside the central shaft assembly 1.

[0037] Specifically, the thrust plate 22 and the rotor 21 can be fixed by welding or bolting. Since the rotor 21 and the thrust plate 22 are fixedly connected, at least a portion of the thrust plate 22 is arranged in the gap of the central shaft assembly 1. The central shaft assembly 1 can provide electromagnetic force for the thrust plate 22 to suspend the thrust plate 22 and limit its axial and radial displacement, thereby achieving suspension of the rotor 21 and limiting the axial and radial displacement of the rotor 21.

[0038] As a preferred or optional embodiment, the central axis assembly 1 includes an axial positioning assembly 11 and a radial positioning assembly 12, and the thrust plate 22 includes an axial positioning portion 221 and a radial positioning portion 222, the axial positioning portion 221 is arranged in the gap in the axial positioning assembly 11, and the radial positioning portion 222 is arranged in the gap between the axial positioning assembly 11 and the radial positioning assembly 12.

[0039] Specifically, the axial positioning portion 221 is arranged in the gap in the axial positioning component 11, and the axial positioning component 11 provides an axial electromagnetic force to the axial positioning portion 221. The axial positioning portion 221 is the force-bearing portion of the rotor component 2 in the axial direction, so that the rotor component 2 is suspended in the axial direction and axial positioning is achieved; the radial positioning portion 222 is arranged in the gap between the axial positioning component 11 and the radial positioning component 12, and the radial positioning component 12 provides a radial electromagnetic force to the radial positioning portion 222. The radial positioning portion 222 is the force-bearing portion of the rotor component 2 in the radial direction, so that the rotor component 2 is suspended in the radial direction and radial positioning is achieved, and the suspension function and the radial and axial positioning functions are integrated on a thrust plate 22, which greatly reduces the volume of the magnetic suspension bearing assembly.

[0040] As a preferred or optional embodiment, the central axis assembly 1 also includes a mounting shaft 13, the axial positioning assembly 11 includes a first axial iron core 111 and a second axial iron core 112, the first axial iron core 111 and the second axial iron core 112 are both sleeved and fixedly mounted on the mounting shaft 13 and the two are arranged at an axial interval along the mounting shaft 13, and the axial positioning portion 221 of the thrust plate 22 is arranged in the gap between the first axial iron core 111 and the second axial iron core 112.

[0041] As a preferred or optional implementation, an axial winding 113 is wound around the first axial iron core 111 and the second axial iron core 112 in an area close to the axial positioning portion 221 to provide an axial electromagnetic force to the rotor assembly 2 .

[0042] Specifically, the first axial core 111 and the second axial core 112 are both made of soft magnetic materials with strong magnetic conductivity, such as 45# steel, and the first axial core 111 and the second axial core 112 are connected to the mounting shaft 13 by interference fit; the first axial core 111 and the second axial core 112 are arranged at intervals along the axial direction of the mounting shaft 13, and the axial positioning portion 221 is arranged in the gap between the two, and the first axial core 111 and the second axial core 112 are wound with axial windings 113, such as Figure 5 As shown, after the current is passed through, the electromagnetic field forms a magnetic flux loop between the first axial iron core 111, the second axial iron core 112, the axial air gap 15 and the thrust plate 22, which can provide electromagnetic force to the axial positioning portion 221; at this time, the current directions of the axial windings 113 passed through the first axial iron core 111 and the second axial iron core 112 are opposite, so opposite electromagnetic forces can be generated, and the magnitudes of the currents in different axial windings 113 are adjusted to make the axial positioning portion 221 suspended in the gap between the first axial iron core 111 and the second axial iron core 112, thereby realizing axial suspension and positioning, and using electromagnetic force for positioning with higher positioning accuracy.

[0043] As a preferred or optional implementation, the axial windings 113 disposed in the first axial core 111 and the second axial core 112 are both wound along the circumferential direction of the mounting shaft 13 .

[0044] As a preferred or optional embodiment, the central axis assembly 1 also includes a mounting shaft 13, the axial positioning assembly 11 is fixedly mounted on the mounting shaft 13, the radial positioning assembly 12 includes a radial iron core 121, the radial iron core 121 is sleeved and fixed on the mounting shaft 13 and there is a gap between the radial iron core 121 and the axial positioning assembly 11 along the radial direction of the mounting shaft 13, and the radial positioning portion 222 of the thrust plate 22 is arranged in the gap between the radial iron core 121 and the axial positioning assembly 11.

[0045] As a preferred or optional implementation, a radial winding 122 is wound inside the radial core 121 to provide radial electromagnetic force to the rotor assembly 2 .

[0046] Specifically, the radial core 121 is composed of silicon steel sheets with strong magnetic conductivity. The use of laminations is conducive to reducing eddy current losses and improving efficiency. It is connected to the mounting shaft 13 by interference fit. The radial winding 122 is wound inside the radial core 121. Figure 3-Figure 4 As shown, after the current is passed through, the electromagnetic field forms a magnetic flux circuit between the radial core 121, the radial air gap 16 and the thrust plate 22, generating a radial electromagnetic force on the radial positioning portion 222, so that the radial positioning portion 222 is suspended in the gap between the radial core 121 and the axial positioning component 11, thereby realizing radial suspension and positioning. The positioning is performed by electromagnetic force, and the positioning accuracy is higher. Moreover, since the axial dimension is reduced, it is more helpful to improve the coaxiality of the magnetic suspension bearing assembly.

[0047] As a preferred or optional implementation, the radial winding 122 disposed in the radial core 121 is wound along the axial direction of the mounting shaft 13 .

[0048] Specifically, the axial winding 113 and the radial winding 122 are both wound by enameled wire.

[0049] As a preferred or optional implementation, the central axis assembly 1 further includes a mounting shaft 13 and a housing 14 , and the mounting shaft 13 is fixedly connected to the housing 14 .

[0050] Specifically, the mounting shaft 13 and the housing 14 are connected by interference fit, and the mounting shaft plays a basic fixing role; the rotor 21 is a shell-like structure, and the housing 14 can cover the mouth of the rotor 21, and enclose the axial positioning component 11 and the radial positioning component 12 in the space formed therein. The rotor 21 can not only play the role of an output shaft, but also protect internal components, further realizing integration, making the structure more compact, and reducing the size.

[0051] The outer rotor motor assembly provided by the present invention comprises a motor stator assembly 3 and a magnetic bearing assembly provided by any technical solution of the present invention; wherein:

[0052] The motor stator assembly 3 is fixedly connected to the central shaft assembly 1 . The rotor assembly 2 includes a rotor 21 and a thrust plate 22 . The thrust plate 22 is fixedly connected to the rotor 21 . The rotor 21 is sleeved outside the motor stator assembly 3 .

[0053] Specifically, the rotor 21 is suspended on the periphery of the motor stator assembly 3, and the motor stator assembly 3 provides a rotating magnetic field; the present invention sets the rotor 21 on the periphery of the motor stator assembly 3, the outer periphery of the magnetic pole, and relative to the inner rotor motor, under the same volume, the outer periphery of the magnetic pole area is larger, under the same current, the output electromagnetic force is larger, and the power is relatively large; the rotor 21 is set on the periphery, the radius of the rotor 21 is larger, and under the same mass, the rotation radius is larger and the inertia is also larger.

[0054] As a preferred or optional embodiment, the motor stator assembly 3 includes a stator core 31 and a stator winding 32 . The stator core 31 is fixedly connected to the central axis assembly 1 , and the stator winding 32 is wound in the stator core 31 along the axial direction of the central axis assembly 1 .

[0055] Specifically, the stator core 31 is made of silicon sheets with strong magnetic conductivity, and the lamination method is conducive to reducing eddy current loss and improving efficiency; the stator winding 32 is made of enameled wire, which is wound inside the stator core 31 to provide a rotating electromagnetic field. In addition, since the rotor 21 is arranged on the periphery of the motor stator assembly 3, compared with the inner rotor motor, under the same volume, the periphery has a larger area, and when the same electromagnetic force is output, the required enameled wire is relatively less, thereby saving the enameled wire.

[0056] The stator core 31 is wound with a stator winding 32, such as Figure 3-Figure 4 As shown, after the current is supplied, the electromagnetic field forms a magnetic flux circuit of the motor between the stator core 31, the motor air gap 4, and the rotor 21, so that the rotor 21 can rotate in the circumferential direction.

[0057] The motor provided by the present invention comprises a motor body and an outer rotor motor assembly provided by any technical solution of the present invention.

[0058] Specifically, the housing 14 in the outer rotor motor group can be the rear housing of the motor, and the rotor 21 can be directly used as an output shaft and connected to loads such as fan blades.

[0059] Unless otherwise stated, any technical solution disclosed in the present invention disclosed above, if it discloses a numerical range, then the disclosed numerical range is a preferred numerical range, and any technician in the field should understand that the preferred numerical range is only a numerical value with a more obvious technical effect or representative value among many implementable numerical values. Since there are too many numerical values ​​to be exhaustive, the present invention discloses some numerical values ​​to illustrate the technical solution of the present invention, and the numerical values ​​listed above should not constitute a limitation on the scope of protection of the present invention.

[0060] If the words "first", "second" and so on are used in this article to limit components, those skilled in the art should know that the use of "first" and "second" is only for the convenience of description to distinguish the components. Unless otherwise stated, the above words have no special meaning.

[0061] Meanwhile, if the above invention discloses or involves mutually fixedly connected parts or structural parts, then, unless otherwise stated, the fixed connection can be understood as: a detachable fixed connection (for example, connection using bolts or screws), or can be understood as: a non-detachable fixed connection (for example, riveting, welding), and of course, the mutually fixed connection can also be an integrated structure (for example, one-piece molding using a casting process) (except where it is obviously impossible to use an integrated molding process).

[0062] In addition, the terms used in any technical solution disclosed in the present invention to indicate positional relationships or shapes include states or shapes that are similar, similar or close to them unless otherwise stated. Any component provided by the present invention may be assembled from multiple separate components or may be a separate component manufactured by an integrated molding process.

[0063] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or some technical features can be replaced by equivalents without departing from the spirit of the technical solution of the present invention, which should be included in the scope of the technical solution for protection of the present invention.

Claims

1. A magnetic bearing assembly, characterized in that: It includes a central shaft assembly and a rotor assembly; wherein, The central shaft component has an accommodating gap, in which at least a portion of the rotor component is disposed, and the central shaft component can provide electromagnetic force to the rotor component to keep the rotor component suspended and at least limit the displacement of the rotor component in its axial and radial directions; The rotor assembly comprises a rotor and a thrust plate, wherein the thrust plate is fixedly connected to the rotor, the rotor is sleeved outside at least a portion of the central shaft assembly, and at least a portion of the thrust plate is disposed in a gap within the central shaft assembly; The central shaft assembly includes an axial positioning assembly and a radial positioning assembly, the thrust plate includes an axial positioning portion and a radial positioning portion, the axial positioning portion is arranged in a gap in the axial positioning assembly, and the radial positioning portion is arranged in a gap between the axial positioning assembly and the radial positioning assembly; The central shaft assembly further includes a mounting shaft, the axial positioning assembly includes a first axial core and a second axial core, the first axial core and the second axial core are both sleeved and fixedly mounted on the mounting shaft and the two are spaced apart along the axial direction of the mounting shaft, and the axial positioning portion of the thrust plate is arranged in the gap between the first axial core and the second axial core; The axial positioning assembly is fixedly mounted on the mounting shaft, and the radial positioning assembly includes a radial iron core, which is sleeved and fixed on the mounting shaft, and there is a gap between the radial iron core and the axial positioning assembly along the radial direction of the mounting shaft, and the radial positioning portion of the thrust plate is arranged in the gap between the radial iron core and the axial positioning assembly.

2. The magnetic bearing assembly according to claim 1, characterized in that: Axial windings are wound around the areas of the first axial iron core and the second axial iron core close to the axial positioning portion, which can provide axial electromagnetic force to the rotor assembly.

3. The magnetic bearing assembly according to claim 2, characterized in that: The axial windings arranged in the first axial iron core and the second axial iron core are both wound along the circumferential direction of the installation shaft.

4. The magnetic bearing assembly according to claim 1, characterized in that: The radial iron core is wound with a radial winding which can provide radial electromagnetic force to the rotor assembly.

5. The magnetic bearing assembly according to claim 2, characterized in that: The radial winding arranged in the radial core is wound along the axial direction of the installation shaft.

6. The magnetic bearing assembly according to claim 1, characterized in that: The central axis assembly also includes a mounting axis and a housing, and the mounting axis is fixedly connected to the housing.

7. An outer rotor motor assembly, characterized in that: It comprises a motor stator assembly and a magnetic bearing assembly as described in any one of claims 1 to 6; wherein: The motor stator assembly is fixedly connected to the central shaft assembly, and the rotor assembly comprises a rotor and a thrust plate. The thrust plate is fixedly connected to the rotor, and the rotor is sleeved outside the motor stator assembly.

8. The outer rotor motor assembly according to claim 7, characterized in that: The motor stator assembly comprises a stator core and a stator winding. The stator core is fixedly connected to the central axis assembly, and the stator winding is wound in the stator core along the axial direction of the central axis assembly.

9. A motor, characterized in that: It comprises a motor body and an outer rotor motor assembly as described in any one of claims 7-8.

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