WO2022007669A1

WO2022007669A1 - Motor and rotor assembly thereof

Info

Publication number: WO2022007669A1
Application number: PCT/CN2021/103281
Authority: WO
Inventors: 孙宁; 石向国; 秦锐锋; 李燕斌
Original assignee: 广东德昌电机有限公司
Priority date: 2020-07-10
Filing date: 2021-06-29
Publication date: 2022-01-13
Also published as: CN113991905A

Abstract

A motor (10) and a rotor assembly (20) thereof. The rotor assembly (20) comprises a columnar rotor core (40), a plurality of permanent magnets (42) mounted on the circumferential surface of the rotor core (40), and a protective cover (60) that is sleeved on the rotor core (40) and covers the permanent magnets (42). At least one axial end face of the rotor core (40) is provided with a plurality of depressions (41) separately extending in the axial direction of the rotor core (40). The protective cover (60) comprises a cylindrical body (70) sleeved on the rotor core (40), and a plurality of snap-fit members (80) that correspondingly extend into and are snap-fitted in the depressions (41) and are connected to the cylindrical body (70).

Description

Electric motors and their rotor assemblies

technical field

The present invention relates to the technical field of motors, and in particular, to a rotor assembly and a motor having the rotor assembly.

Background technique

In the rotor of a permanent magnet motor, the permanent magnets are usually installed on the circumferential surface of the rotor iron core, and a protective cover is further sleeved to prevent the permanent magnets from separating from the rotor iron core when the rotor rotates at a high speed. However, for a good protective effect, the protective cover needs to be further fixed with the rotor core. In the prior art, the protective cover can be fixed to the rotor core by spot welding. In the actual production process, the spot welding method brings a lot of inconvenience. complex and long-term.

technical problem

In view of this, the present invention aims to provide a rotor assembly that can solve or at least alleviate the above-mentioned problems and a motor having the rotor assembly.

technical solutions

In one aspect, the present invention provides a rotor assembly, comprising a cylindrical rotor core, a plurality of permanent magnets mounted on the circumferential surface of the rotor core, and a protective cover sleeved on the rotor core and covering the permanent magnets , at least one axial end surface of the rotor iron core is provided with a plurality of recesses extending along the axial direction of the rotor iron core, the protective cover comprises a cylindrical body sleeved on the rotor iron core, and a The cylindrical body is connected with a plurality of corresponding holding pieces extending into and holding the recesses.

In some embodiments, each of the holding members includes an elongated body portion, and one end of the body portion is connected to the axial end of the cylindrical body of the protective cover.

In some embodiments, the body portion is bent to form an elastic body, and the elastic body is clamped into the dimple and is restricted by the shape of the dimple to maintain an elastic force state, so that the clamping member can be made by the elasticity of the elastic body. snap into the corresponding recess.

In some embodiments, the elastomer is V-shaped.

In some embodiments, the body portion includes a first section extending obliquely with respect to an axial direction of the rotor core from an opening of the pocket into the pocket, and an end from the first section A second section extending obliquely with respect to the axial direction of the rotor core at the opening of the pocket.

In some embodiments, the body portion of the holding member is straight and extends obliquely with respect to the axial direction of the rotor core.

In some embodiments, each of the holding members further includes a plurality of thorns formed on the periphery of the body portion, the thorns corresponding to the inner wall of the recess.

In some embodiments, the spikes of each holder are symmetrically distributed on the periphery of the main body of the holder.

In some embodiments, the spurs are all triangular in shape with the periphery of the body portion as one side, and the free angle of the spurs ranges from 30° to 60°.

In some embodiments, the protuberances are all in the shape of a right-angled triangle, and the perimeter of the corresponding body portion is a right-angled side, and the other right-angled side of the spurs faces the opening of the pit where the protuberance is located.

In some embodiments, the cylindrical body of the protective cover includes a cylindrical axially extending portion, and an annular radially extending portion extending radially inward from one end of the axially extending portion, the The retaining member further extends radially inwardly from the radially inner edge of the radially extending portion.

In some embodiments, the cylindrical body and the holding member of the protective cover are integrally formed from deformable elastic materials.

In some embodiments, the protective cover radially clamps the permanent magnets to prevent the permanent magnets from disengaging from the rotor core.

In some embodiments, the number of the protective covers is two, and they are respectively sleeved on the rotor iron core from two axial end faces of the rotor iron core.

In some embodiments, the depth of each of the pockets is less than the axial length of the rotor core.

In some embodiments, the rotor core is formed by stacking a plurality of laminations, and at least the laminations within a certain distance from one or both ends of the rotor core are provided with through holes, and the through holes of these laminations are provided with through holes. The dimples are formed by being axially aligned.

In another aspect, the present invention also provides a motor including a stator and the rotor assembly accommodated in the stator.

beneficial effect

When the rotor assembly of the present invention is assembled, it is only necessary to first cover the protective cover on the surface of the rotor iron core, and then press the holding part of the protective cover into the pit of the rotor iron core so that the holding part is held in the pit. Assembly costs and assembly man-hours are reduced.

Description of drawings

Further features of the present invention will become apparent from the following description of preferred embodiments, which are provided by way of example only in connection with the accompanying drawings, wherein:

FIG. 1 is a schematic structural diagram of an embodiment of the motor of the present invention.

FIG. 2A is a perspective structural view of the first embodiment of the rotor assembly of the present invention.

Figure 2B is a cross-sectional view of the rotor assembly shown in Figure 2A.

Figure 2C is an exploded view of the rotor assembly shown in Figure 2A.

FIG. 2D is an assembled state view of the rotor assembly shown in FIG. 2A , wherein the retaining member of the protective cover has not yet been pressed into the recess of the rotor core.

Fig. 2E is a partial enlarged view of the retainer of the rotor assembly shown in Fig. 2C.

Figure 2F is a cross-sectional view of a rotor assembly relative to another embodiment of the rotor assembly shown in Figure 2B.

Figure 3 is an exploded view of a second embodiment of the rotor assembly of the present invention.

Figure 4 is an exploded view of a third embodiment of the rotor assembly of the present invention.

Embodiments of the present invention

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments, so as to make the technical solutions and beneficial effects of the present invention clearer. It should be understood that the accompanying drawings are only used for reference and description, and are not used to limit the present invention, and the dimensions shown in the accompanying drawings are only for the convenience of clear description, and do not limit the proportional relationship.

Referring to FIG. 1 , the present invention provides a motor 10 , the motor 10 includes a stator 11 , and a rotor assembly 20 accommodated in the stator 11 and rotatable in the stator 11 . The stator 11 may adopt the existing stator structure, which will not be repeated here. The rotor assembly 20 may adopt the rotor assemblies in the following embodiments.

FIGS. 2A to 2C show the first embodiment of the rotor assembly 30 of the present invention, which includes a rotor core 40 , a rotating shaft 50 penetrating the rotor core 40 , a permanent magnet 42 mounted on the circumferential surface of the rotor core 40 , and a sleeve A protective cover 60 is provided on the rotor core 40 . The axial ends of the rotor core 40 are respectively provided with a plurality of recesses 41 with a certain axial depth. The protective cover 60 clamps the permanent magnets 42 radially to prevent the permanent magnets 42 from being separated from the rotor core 40 . The protective cover 60 includes a cylindrical body 70 covering the surface of the rotor core 40 , and a holding member 80 connected to the cylindrical body 70 . The holding member 80 extends into the cavity 41 from the axial end face of the rotor core 40 and is clamped on the inner wall of the cavity 41 . Different from the existing welding method, when the rotor assembly 30 in this embodiment is assembled, it is only necessary to set the protective cover 60 on the surface of the rotor core 40 first, and then deform and press the holding member 80 of the protective cover 60. It only needs to be inserted into and clamped in the recess 41 of the rotor iron core 40 , which reduces the assembly cost and assembly man-hours.

Preferably, the rotor core 40 is formed by stacking a plurality of laminations 401 in the axial direction of the rotor. Each lamination is provided with a plurality of through holes 402 , and the through holes 402 of these laminations 401 are aligned in the axial direction to form the recesses 41 . Therefore, the dimples 41 penetrate the rotor core in the axial direction. It can be understood that, as shown in FIG. 2F , in another embodiment, only the laminations 401 within a certain distance from both ends of the rotor core 40 are provided with these through holes 402 , while other laminations 401 are not provided with these through holes 402 . The depth of the hole 402 , that is, the recess 41 is smaller than the axial length of the rotor core 40 . In this embodiment, the number of the pits 41 is eight.

Preferably, in this embodiment, the number of the protective covers 60 is two, and the two protective covers 60 have the same structure and are respectively sleeved on the rotor iron core 40 from opposite axial ends of the rotor iron core 40 . Therefore, the specific structure and arrangement of the protective cover 60 in the upper part of the figure will be described below as an example.

Specifically, an opening 63 is formed at one end (shown as an axial lower end) of the protective cover 60 to allow the protective cover 60 to be sleeved on the rotor iron core 40 from the axial upper end of the rotor iron core 40 . The other end of the protective cover 60 (shown as an axial upper end) is connected to the holding member 80 . Corresponding to the eight dimples 41 of the rotor core 40 , the protective cover 60 also preferably includes eight retaining members 80 evenly distributed along the circumferential direction. The protective cover 60 is fixed on the rotor iron core 40 through a plurality of holding parts 80, and the fixing effect is good. Preferably, the protective cover 60 is an integral piece, so as to enhance the connection strength between the holding member 80 and the cylindrical body 70 . More preferably, the protective cover 60 is integrally made of deformable elastic material, such as steel. In this way, each holding member 80 of the protective cover 60 can be better held in the corresponding recess 41 by virtue of its elastic deformation characteristics.

Preferably, the cylindrical body 70 of the protective cover 60 includes a cylindrical axially extending portion 71 , and an annular annular extending portion 71 radially inwardly extending from one end of the axially extending portion 71 (shown as an axial upper end). Radial extension 72 . The axially extending portion 71 is sleeved on the outer periphery of the rotor iron core 40 , and the radially extending portion 72 covers the axial upper end surface of the rotor iron core 40 . Preferably, the radial width of the radial extension 72 ensures that it at least does not cover the recess 41 . During assembly, the protective cover 60 can be initially positioned to the rotor core 40 through the structural arrangement of the cylindrical body 70 of the protective cover 60 in this embodiment.

Preferably, the holding member 80 of the protective cover 60 includes a body portion 81 further radially extending from the radially inner edge of the radially extending portion 72 , and a thorn formed on the periphery of the body portion 81 . 82 , the spikes 82 are clamped on the inner wall of the recess 41 , so as to fix the protective cover 60 to the rotor core 40 . Considering that the rotor core 40 is formed by stacking a plurality of laminations 401, the inner wall of the dimple 41 increases the surface roughness due to the interface between the adjacent laminations 401, and the relationship between the spike 82 and the inner wall of the dimple 41 increases. The frictional force between the two is increased, so that the thorns 82 are easily clamped on the inner wall of the recess 41 and the fixing strength of the protective cover 60 is improved.

Referring to FIG. 2D and FIG. 2E , FIG. 2D shows a state diagram when the holding member 80 has not yet been pressed into the recess 41 , which is an elongated flat strip 800 extending radially inward. After being deformed and bent, the elongated body portion 81 forms a substantially V-shaped elastic body. It can be understood that, in other embodiments, the main body portion 81 may be formed into other shapes of elastic bodies, such as a W shape. It can be understood that during installation, the elastic body of the holding member 80 is clamped into the corresponding dimple 41 of the rotor iron core 40 and is restricted by the shape of the dimple to maintain an elastic force state, so that the elastic body of the elastic body makes the clamping The holder 80 is snapped into the corresponding recess 41 .

Preferably, the flat strip 800 covers right above the dimple 41 and extends to the radially inner side of the dimple 41 when the flat strip 800 is not yet pressed into the dimple 41 . The bent flat strip, that is, the body portion 81 of the holding member 80 includes a transition section 83 extending radially inward from the radially extending portion 72 , and extending radially inward from the transition section 83 . A first section 85 extending downward, and a second section 87 extending radially inward and upward from the first section 85 . The transition section 83 covers the axial upper end face of the rotor core 40 . The design of the transition section 83 is beneficial to enhance the connection strength between the holding member 80 and the cylindrical body 70 of the protective cover 60, and avoid problems such as breakage when the flat strip is bent. It can be understood that in other embodiments, the transition section 83 can be omitted. The first segment 85 and the second segment 87 are accommodated in the recess 41 and are arranged in a substantially V-shape, wherein the first segment 85 extends obliquely into the recess 41 from the opening of the recess 41, Two sections 87 extend obliquely from the end of the first section towards the opening of the pit. In other words, the holding member 80 in this embodiment includes two bending parts 88 and 89 , one bending part 88 is located between the transition section 83 and the first section 85 , and the other bending part 89 is located in the first area between segment 85 and second segment 87 .

In this embodiment, each of the holding members 80 is provided with six of the protruding protrusions 82 . The two protruding protrusions 82 respectively protrude and extend outward from the two side edges 850 of the first section 85 . The two protruding protrusions 82 respectively protrude and extend outward from the two side edges 870 of the second section 87 , and the other two protruding protrusions 82 protrude and extend outward from the end edge 871 of the second section 87 . The side edge 850 of the first segment 85 defined in this embodiment is the side surface of the first segment 85 extending along the length and thickness directions of the holding member 80 . Similarly, the side edge 870 of the second segment 87 is the side surface of the second segment 87 extending along the length and thickness directions of the holder 80 . The end edge 871 of the second segment 87 is a plane of the second segment 87 extending along the width and thickness directions of the holder 80 . Through the arrangement of these protruding protrusions 82, the holding member 80 can be fixed at six different stress points in one housing, and since these protruding protrusions 82 are symmetrically arranged on the periphery of the body portion 81, they can be clamped in the concave The opposite inner walls of the pit 41 have a good clamping effect.

In this embodiment, the protruding protrusions 82 are all triangles with the periphery of the main body portion 81 as one side, and are in the same plane as the segment where they are located. The angle range of the free angle of each protruding protrusion 82 (the angle opposite to the peripheral edge of the main body portion 81 ) is 30° to 60°, preferably about 45°. Preferably, the protruding protrusions 82 are generally in the shape of a right-angled triangle, and the peripheral edge of the corresponding body portion 81 is a right-angled side. The other right-angled sides of the thorns 82 located on the side edge 850 of the first segment 85 and the side edge 870 of the second segment 87 face upwards relatively (ie, toward the opening of the dimple 41 ), which helps to improve the thorn The engagement strength between the protrusion 82 and the inner wall of the recess 41 is increased to prevent the spur 82 from slipping out of the recess 41 . It will be appreciated that in other embodiments, other structures and/or arrangements of the spikes 82 may also be employed.

When assembling the rotor assembly 30 in this embodiment, the two protective covers 60 are firstly sleeved into the rotor core 40 from opposite ends in the axial direction, and then the flat bars 800 are pressed into the recesses 41 to form the holding members 80 . At the time, the protruding protrusions 82 are all clamped in the inner wall of the recess 41, so as to stably fix the protective cover 60 and the rotor core 40 together.

Referring to FIG. 3 , the second embodiment of the rotor assembly 130 of the present invention is similar to the first embodiment of the rotor assembly 30 described above, and the same parts will not be repeated here. The main difference between this embodiment and the first embodiment is: this In the embodiment, the protruding protrusions 82 of the holding member 180 are all formed on the periphery of the second section 87 of the body portion 81 , and similarly, the protruding protrusions 82 can be clamped on the inner wall of the recess 41 to secure the protective cover. 160 is fixed on the rotor core 40 .

Referring to FIG. 4 , the third embodiment of the rotor assembly 230 of the present invention is similar to the first embodiment of the rotor assembly 30 described above, and the same parts are not repeated here. The main differences between this embodiment and the first embodiment are: this The holder 280 in the embodiment no longer includes the spikes 82 . The holding member 280 in this embodiment is formed by bending a rectangular flat strip. The two right angles 284 of the free end of the flat strip are directly used to hold the holding member 280 on the inner wall of the recess 41 , and the protective cover 260 can also be clamped. It is fixed to the rotor core 40 .

It can be understood that in other embodiments, the aforementioned holding members 80 , 180 , 280 with two bending parts may not be used, or a holding member (not shown) with only one bending part may be used. . For example, the elastic body of the main body of the holding member may be straight, which is accommodated in the recess 41 and extends obliquely with respect to the axial direction of the rotor core. Or a plurality of thorns can be clamped on the inner wall of the recess 41 by the thorns on the periphery of the straight body portion, and the protective cover can also be fixed on the rotor core 40 .

It can also be understood that the entire clamping part can also be directly pressed into the recess 41 . In other words, in other embodiments, the holder may no longer include the transition section 83 .

The above descriptions are only preferred specific embodiments of the present invention, and the protection scope of the present invention is not limited to the above-listed embodiments. Any person skilled in the art who is familiar with the technical field of the present invention can obviously obtain the technical Simple changes or equivalent replacements of the solutions all fall within the protection scope of the present invention.

Claims

A rotor assembly includes a columnar rotor core, a plurality of permanent magnets mounted on the circumferential surface of the rotor core, and a protective cover sleeved on the rotor core and covering the permanent magnets, characterized in that the At least one axial end surface of the rotor iron core is provided with a plurality of dimples extending along the axial direction of the rotor iron core, and the protective cover includes a cylindrical body sleeved on the rotor iron core, and a cylindrical body with the cylindrical body. A plurality of corresponding holding pieces that are connected to the body are inserted into and held in the recesses.
The rotor assembly according to claim 1, wherein each of the holding members comprises a long body portion, and one end of the body portion is connected to the axial end of the cylindrical body of the protective cover.
The rotor assembly according to claim 2, wherein the body portion is bent to form an elastic body, the elastic body is clamped into the dimple and is restricted by the shape of the dimple to maintain an elastic force state, so as to use The elasticity of the elastic body makes the clips clamp in the corresponding recesses.
4. The rotor assembly of claim 3, wherein the elastomer is V-shaped.
5. The rotor assembly of claim 4, wherein the body portion includes a first section extending obliquely with respect to an axial direction of the rotor core from the pocket opening into the pocket, and a self- The end of the first segment faces toward the second segment extending obliquely with respect to the axial direction of the rotor core at the pocket opening.
The rotor assembly according to claim 3, wherein the body portion of the holding member is straight and extends obliquely with respect to the axial direction of the rotor core.
The rotor assembly according to any one of claims 2 to 6, wherein each of the retaining members further comprises a plurality of protruding protrusions formed on the periphery of the main body portion, the protruding protrusions correspondingly clamped in the recesses inner wall of the pit.
The rotor assembly according to claim 7, wherein the thorns of each holding member are symmetrically distributed on the periphery of the body portion of the holding member.
The rotor assembly according to claim 7, wherein the spurs are all triangular in shape with the periphery of the body portion as one side, and the free angle of the spurs ranges from 30° to 60°.
The rotor assembly according to claim 9, wherein each of the spurs is in the shape of a right-angled triangle, and the periphery of the corresponding body portion is a right-angled side, and another right-angled side of the spurs faces the opening of the pit where the spurs are located. .
The rotor assembly according to claim 1, wherein the cylindrical body of the protective cover comprises a cylindrical axially extending portion, and a ring-shaped radially inwardly extending portion from one end of the axially extending portion The radially extending portion of the retaining member further extends radially inward from the radially inner edge of the radially extending portion.
The rotor assembly according to any one of claims 1-6 and 11, wherein the cylindrical body and the holding member of the protective cover are integrally formed from deformable elastic materials.
The rotor assembly according to any one of claims 1-6 and 11, wherein the protective cover clamps the permanent magnets radially to prevent the permanent magnets from detaching from the rotor core.
The rotor assembly according to any one of claims 1 to 6 and 11, wherein the number of the protective covers is two, and they are respectively sleeved on the two axial end faces of the rotor iron core opposite to each other. the rotor core.
The rotor assembly of any one of claims 1-6 and 11, wherein the depth of each of the pockets is less than the axial length of the rotor core.
The rotor assembly according to any one of claims 1-6 and 11, wherein the rotor core is formed by stacking a plurality of laminations, at least a certain distance from one or both ends of the rotor core The laminations in the range are provided with through holes which are axially aligned to form the pockets.
An electric motor includes a stator, and a rotor assembly according to any one of claims 1-16 accommodated in the stator.