CN219697370U - Stator core, motor and electric drive system - Google Patents

Abstract

The utility model relates to a stator core, a motor and an electric drive system, wherein the stator core comprises: a first member having a ring shape and a first diameter on an outer periphery thereof, the outer periphery being provided with a recess; a second member having a ring shape and a first diameter on an outer periphery thereof, wherein a sinking region is provided on the outer periphery thereof, the sinking region of the second member has a recess portion, and the recess portion of the sinking region and the recess portion of the first member are located at the same position in a circumferential direction; the periphery of the third member is provided with a protruding part, the protruding part of the third member is provided with a recessed part, and the recessed part of the protruding part of the third member and the recessed part of the first member are at the same position in the circumferential direction; the protruding portion of the third member has a smaller dimension in the circumferential direction than the sinking region of the second member. According to the scheme, the stator core improves the strength of the welding seam and ensures the cooling performance.

Description

Stator core, motor and electric drive system

Technical Field

The utility model relates to the technical field of motors, in particular to a stator core, a motor and an electric drive system.

Background

The main components of the motor include a stator assembly and a rotor assembly. Typically, the stator assembly includes a stator core and stator windings, and the rotor assembly includes a rotor and rotor windings or permanent magnets. The stator winding is mounted on the stator core, and when a current is passed through the stator winding, a magnetic field is generated in the stator core. The magnetic field interacts with the rotor assembly to rotate the rotor, converting electrical energy into mechanical energy.

Due to losses such as iron loss, copper loss, eddy current loss, etc., heat is inevitably generated during operation of the motor, which requires cooling of the components such as windings of the motor. In addition, as the requirements of new energy automobiles on motor performance are higher, the power and the rotating speed of the motor are higher, and the heat generated during the operation of the motor is correspondingly increased. Accordingly, there is a continuing need in the art of electric machines for improvements in cooling technology for electric machines.

Disclosure of Invention

In combination with research and improvement of the motor cooling technology by the applicant, the utility model provides the following technical scheme for further improving the cooling performance of the motor.

A stator core, comprising:

a first member having a ring shape and an outer periphery of which has a first diameter, a recess being provided on the outer periphery;

the stator core further includes:

a second member having a ring shape and an outer periphery thereof having a first diameter, a sinking region being provided at the outer periphery thereof, the sinking region being located between a circle having the first diameter and a circle having a second diameter in a radial direction, the second diameter being smaller than the first diameter, the second member having a recess located inside the circle having the second diameter in the radial direction and at the same position in the circumferential direction as the recess of the first member;

a third member having a ring shape and an outer periphery thereof having a second diameter smaller than the first diameter, a protruding portion being provided at the outer periphery thereof, the protruding portion having a recessed portion, the recessed portion of the protruding portion of the third member being at the same position in the circumferential direction as the recessed portion of the first member;

the protruding portion of the third member has a smaller dimension in the circumferential direction than the sinking region of the second member.

According to one aspect of the utility model, the number of the first members is plural, and the plural first members form a first group of first members and a second group of first members, the second members and the third members being located between the first group of first members and the second group of first members.

According to an aspect of the present utility model, the number of the second members is plural, and the plurality of the second members form a first group of the second members and a second group of the second members, and the number of the third members is plural, the plurality of the third members being closely arranged to each other and located between the first group of the second members and the second group of the second members.

According to one aspect of the present utility model, a plurality of holes are provided in the first member, the number of the concave portions is plural, the plurality of holes do not overlap with the concave portions in the circumferential direction, and at least a part of the holes is located between the first diameter and the second diameter.

According to an aspect of the present utility model, the plurality of holes are divided into a plurality of sections in the circumferential direction, and the plurality of holes in each section are uniformly arranged in the circumferential direction.

According to one aspect of the utility model, a plurality of holes are provided on the second member, and the plurality of holes on the second member are circumferentially spaced apart from the sinking region; the number of holes on the second member is smaller than the number of holes on the first member, and the number of recesses on the second member is the same as the number of recesses on the first member.

According to an aspect of the present utility model, the plurality of holes on the first member and the plurality of holes on the second member form a plurality of flow passages in the axial direction, and the holes forming each flow passage are staggered in the axial direction.

According to one aspect of the utility model, the outer circumference of the protruding portion of the third member has a first diameter.

The utility model also provides a motor which is provided with a shell, and the motor also comprises the stator core.

The utility model also provides an electric drive system which is provided with at least one of a speed reducer and an inverter, and the electric drive system also comprises the motor.

According to the scheme of the utility model, when the three laminations are combined to form the stator core, as the third component with the protruding part is arranged at the middle part of the stator core, the protruding part is added at the corresponding welding line position, the outer diameter of the protruding part is consistent with that of the first component, and a corresponding support is formed on the first runner after a plurality of different laminations are welded, so that the deformation difference at the welding line can be reduced, the shearing stress generated at the welding line can be greatly reduced, and the risk of cracking the welding line can be reduced or even eliminated. In addition, the flow passage in the circumferential direction can also form a ring shape, so that the cooling effect is ensured.

Other features and advantages of the present utility model will be described in the following detailed description of the utility model, taken in conjunction with the accompanying drawings.

Drawings

Exemplary embodiments of the present utility model are described with reference to the accompanying drawings, in which:

fig. 1 shows a perspective view of a stator core of the present utility model.

Fig. 2 shows a top view of a first member constituting the stator core.

Fig. 3 shows a top view of a second member constituting the stator core.

Fig. 4 shows a top view of a third member constituting the stator core.

All the figures are schematic and not necessarily to scale, and they show only those parts which are necessary in order to elucidate the utility model, the other parts being omitted or merely mentioned. That is, the present utility model may include other components in addition to those shown in the drawings.

In the drawings, identical and/or functionally identical technical features are provided with the same or similar reference signs.

Detailed Description

Embodiments of the present utility model are described below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding and enabling description of the utility model to one skilled in the art. It will be apparent, however, to one skilled in the art that the present utility model may be practiced without some of these specific details. Furthermore, it should be understood that the utility model is not limited to specific described embodiments. Rather, any combination of the features and elements described below is contemplated to implement the utility model, whether or not they relate to different embodiments. Thus, the following aspects, features, embodiments and advantages are merely illustrative and should not be considered features or limitations of the claims except where explicitly set out in a claim.

Description of orientations such as "upper", "lower", "inner", "outer", "radial", "axial", etc. which may be used in the following description are for convenience of description only and are not intended to limit the inventive arrangements in any way unless explicitly stated. Furthermore, terms such as "first," "second," and the like, are used hereinafter to describe elements of the present utility model, and are merely used for distinguishing between the elements and not intended to limit the nature, sequence, order, or number of such elements.

Fig. 1 shows a perspective view of a stator core of the present utility model. As can be seen in fig. 1, the stator core 10 is generally cylindrical in shape having an outer surface and an interior cavity for receiving a rotor assembly. On the outer surface of the stator core 10, a first flow passage 11 in the circumferential direction is opened, and the first flow passage 11 is substantially annular in shape as a whole. The first flow passage 11 is preferably located at the middle of the stator core in the axial direction. On the stator core 10, there are also provided a plurality of second flow passages 12 extending axially, the plurality of second flow passages 12 being preferably uniformly distributed in groups in the circumferential direction in a manner to be described later, and being located at the same position near the outer surface in the radial direction. The first flow passage 11 and the plurality of second flow passages 12 are in fluid communication.

In order to accommodate the stator winding, the stator core 10 is provided with a plurality of stator teeth 13 on a radially inner side thereof, and tooth slots 14 are formed between the stator teeth 13, the tooth slots 14 being for accommodating a portion of the stator winding.

The stator core 10 of the present utility model is formed from a plurality of stator laminations. The stator lamination may be made of silicon steel sheets. Accordingly, in order to construct the plurality of stator laminations as one unitary stator core, a recess is provided on the outer periphery of each stator lamination so that the plurality of stator laminations are formed into one unitary body by welding at the location of the recess. Fig. 1 shows such a recess 15. When all stator laminations are stacked, the recess of each stator lamination forms a recess that is continuous in the axial direction.

As previously mentioned, the second flow passage 12 is located radially close to the outer surface, but should be at a distance from the outer surface. This is because the stator core needs to be fitted into the housing by means of an interference fit, and if the second flow passage 12 is too close to the outer surface, the strength of the entire stator core may not be satisfactory; on the other hand, because the second flow channel 12 needs to be in fluid communication with the first flow channel 11, the depth of the first flow channel 11 cannot be too deep, which would otherwise lead to weakening of the stator strength and a large difference in the dimensions of the stator core at this location from those at other locations, thereby affecting the electromagnetic performance of the motor. Meanwhile, as can also be seen from fig. 1, the second flow passage 12 is located at a distance from the recess 15 in the circumferential direction, so that the influence on the strength of the stator core can be avoided.

An important improvement of the utility model is the structural design at the first flow channel 11 and the recess 15. The structural design will be described in detail below in conjunction with other figures.

As can be seen from fig. 1, the plurality of laminations constituting the stator core 10 can be divided into 3 types, the first being the first member 101, the second being the second member 102, and the third being the third member 103, according to whether or not the outer peripheral surface thereof participates in forming the first flow passage 11, wherein the outer peripheral surface of the first member 101 does not participate in forming the first flow passage 11 at all, a small portion of the outer peripheral surface of the second member 102 participates in forming the first flow passage 11, and a large portion of the outer peripheral surface of the third member 103 participates in forming the first flow passage 11. The structures of the first member, the second member, and the third member are described in detail below with reference to fig. 2, 3, and 4.

Fig. 2 shows a top view of a first member constituting the stator core. The outer contour/peripheral surface of the first member 101 shown in fig. 2 has a first diameter. The first member 101 is located on both sides of the second member and the third member in the axial direction of the stator core. The first member 101 is provided with a recess 15 on its outer surface and a plurality of holes 121 in its radial position close to the outer surface so as to form the first flow channel 12 together with corresponding holes on the other first member or with corresponding holes on the second member.

As a preferred embodiment, the plurality of holes in the first member and the plurality of holes in the second member form a plurality of flow passages in the axial direction, and the holes forming each flow passage are staggered in the axial direction. That is, the plurality of holes forming one flow passage are not perfectly aligned but are staggered as viewed in the axial direction, and the flow passage thus formed is not a straight flow passage but a meandering flow passage, which can increase the flow time and flow length of the cooling liquid in the flow passage, thereby improving the cooling effect.

The holes 121 may have various shapes. For example, it may be a quadrilateral. Further, the first member may be rectangular, or may be an arc with two sides parallel to the peripheral outline of the first member, and the other two sides being parallel line segments, or may be an arc with two sides parallel to the peripheral outline of the first member, and the other two sides being located on two diameters.

The plurality of holes 121 are divided into a plurality of sections by the recess 15 in the circumferential direction of the first member, and in each section, the plurality of holes 121 are uniformly arranged in the circumferential direction. The hole 121 adjacent to the recess 15 is located at a distance from the recess 15 in the circumferential direction. As can be seen from fig. 2, no hole 121 is provided in the radial direction in which the recess 15 is provided. The recess 15 is located circumferentially between the two holes 121, but also need not be exactly in the middle of the two holes 121. The recesses 15 are preferably also circumferentially distributed, the number of which may be 8, for example, although other numbers are possible, provided that the overall strength of the stator is ensured.

The bore 121 is preferably located radially between a first diameter and a second diameter, which will be defined below, thereby enabling the second flow passage 12 to be in substantial fluid communication with the first flow passage 11.

Fig. 3 shows a top view of a second member constituting the stator core. The contour of the outer peripheral surface of the second member 102 shown in fig. 3 also has a first diameter. Unlike the first member 101, on the outer peripheral surface of the second member 102, a plurality of depressed areas 16 are provided, the depressed areas 16 enabling the second member 102 to have fewer holes 121 than the first member 101. Specifically, the depressed area 16 may be a quadrilateral in which two sides are two circular arcs corresponding to the first diameter and the second diameter, respectively, and the other two sides are located between the two circular arcs. The other two sides can be respectively overlapped with the two diameters, or can be parallel to each other. The particular shape of the countersink 16 is important in that after the stator core is formed, the countersink 16 is able to cooperate with a raised portion on a third member, which will be described in detail below, to form a transition portion of the first flow channel 11.

In order to connect the second members 102 to each other and also connect the second members 102 to the first member 101 adjacent thereto or to the third member 103 to be described later, it is also necessary to provide the recess 15 on the second member 102. The recess 15 on the second member 102 is provided in the countersink region 16, preferably in a middle portion of the countersink region 16 in the circumferential direction. That is, the recess 15 on the second member 102 continues to recess radially inward on one side of the countersunk region 15. Since the recess 15 on the second member 102 is radially recessed from the circular arc corresponding to the second diameter, the recess depth of the recess 15 on the second member 102 is relatively smaller than the recess 15 on the first member 101 that is radially recessed from the circular arc corresponding to the first diameter.

Fig. 4 shows a top view of a third member constituting the stator core. The outer peripheral surface profile of the third member 103 shown in fig. 4 has a second diameter. Further, as can be seen in connection with fig. 1 to 4, the third members 103 are located between all of the first members and the second members in the axial direction of the entire stator core, and the plurality of third members 103 are closely arranged in the axial direction, and two third members located at the axially outermost sides of the section composed of the third members 103 are in contact with the second members. In the axial direction of the stator core, a plurality of members are arranged in this order, respectively, such that a part of the first member, a part of the second member, all of the third member, a part of the second member, and a part of the first member are arranged.

Since the second diameter is smaller than the first diameter, half of the difference between the first diameter and the second diameter is the depth of the first flow channel 11.

As shown in fig. 4, on the outer peripheral surface of the third member 103, a plurality of protruding portions 1031 are provided. The protrusion 1031 extends radially outward from the outer peripheral surface of the third member 103 to a first diameter. That is, the protruding portion 1031 is also a quadrangle, in which two sides are two circular arcs having a first diameter and a second diameter, respectively, and the other two sides may be overlapped with the two diameters, respectively, or may be parallel to each other.

In order to connect the third members 103 to each other and also connect the third members 103 to the second members 102 adjacent thereto, it is also necessary to provide the recess 15 on the third members 103. Specifically, the recess 15 is provided on the protrusion 1031. The depth of the recess 15 on the third member 103 may be the same as the shape of the recess on the first member.

As can be seen in connection with fig. 1 to 4, after the stator core shown in fig. 1 is assembled by using the three kinds of laminations shown in fig. 2 to 4, the recesses 15 on the first member 101, the second member 102, and the third member 103 are aligned, thereby forming a continuous bead. The portions of the first, second and third members 101, 102, 103 having the first diameter can contact the housing of the motor after assembly to form a tight fit or interference connection. The outer peripheral surfaces of the second member 102 and the third member 103 having the second diameter define the bottom surface of the first flow passage 11. The holes 121 in the first member 101 and the second member 102 form a second flow path.

The first flow passage 11 forms a bend at the protruding portion 1031 of the third member 103 and the sinking region 16 of the second member, but is communicated in the circumferential direction as a whole. The specific dimensions of the first flow passage 11, i.e., the values of the first diameter and the second diameter, the number of the second members, the number of the third members, the sinking region of the second members, and the size of the protruding portion of the third members, may be set as desired.

In the prior art, the stator core is formed of only two members, a member having a first diameter and a member having a second diameter, respectively. The members having the second diameter are positioned between the members having the first diameter, and a coolant passage is formed at the intermediate position by the difference in outer diameter so that the coolant flows along the entire intermediate groove, and the laminations are joined by a weld. In this stator core, during assembly, since the lamination materials of the housing and the stator of the motor are different, they have different thermal deformation coefficients, so that deformation amounts at different temperatures are different, for example, at low temperature, lamination areas on two sides can be subjected to radial inward extrusion force of the housing, but a member with a second diameter is not subjected to radial extrusion force of the housing, and different deformation amounts can generate shear stress at the joint of welding seams of adjacent different members, so that quality risks such as welding seam cracking can be caused.

Therefore, compared with the scheme adopting only two types of lamination, when the three types of lamination are combined to form the stator core, as the third component with the protruding part is arranged at the middle part of the stator core, the protruding part is added at the corresponding welding line position, the outer diameter of the protruding part is consistent with that of the first component, and corresponding supports are formed on the first runner after welding a plurality of different lamination, so that deformation difference at the welding line can be reduced, further shearing stress generated at the position can be greatly reduced, and the risk of cracking of the welding line can be reduced or even eliminated.

While the present utility model has been described with respect to the above exemplary embodiments, it will be apparent to those skilled in the art that various other embodiments can be devised by modifying the disclosed embodiments without departing from the spirit and scope of the utility model. Such embodiments should be understood to fall within the scope of the utility model as determined based on the claims and any equivalents thereof.

Claims (10)

1. A stator core, comprising:

a first member having a ring shape and an outer periphery of which has a first diameter, a recess being provided on the outer periphery;

the stator core further includes:

a second member having a ring shape and an outer periphery thereof having a first diameter, a sinking region being provided at the outer periphery thereof, the sinking region being located between a circle having the first diameter and a circle having a second diameter in a radial direction, the second diameter being smaller than the first diameter, the second member having a recess located inside the circle having the second diameter in the radial direction and at the same position in the circumferential direction as the recess of the first member;

a third member having a ring shape and an outer periphery thereof having a second diameter, a protruding portion being provided at the outer periphery thereof, the protruding portion of the third member having a recessed portion, the recessed portion of the protruding portion of the third member being at the same position in the circumferential direction as the recessed portion of the first member;

the protruding portion of the third member has a smaller dimension in the circumferential direction than the sinking region of the second member.

2. The stator core as claimed in claim 1, wherein,

the number of first members is plural, and the plural first members form a first group of first members and a second group of first members, with the second members and the third members being located between the first group of first members and the second group of first members.

3. The stator core as claimed in claim 2, wherein,

the number of the second members is plural, and the plural second members form a first group of second members and a second group of second members, and the number of the third members is plural, and the plural third members are closely arranged to each other and are located between the first group of second members and the second group of second members.

4. The stator core according to any one of claim 1 to 3, wherein,

a plurality of holes are provided in the first member, the number of the recesses is plural, the plurality of holes do not overlap with the recesses in the circumferential direction, and at least a portion of the holes are located between the first diameter and the second diameter.

5. The stator core as claimed in claim 4, wherein,

the plurality of holes are divided into a plurality of sections in the circumferential direction, and the plurality of holes in each section are uniformly arranged in the circumferential direction.

6. The stator core as claimed in claim 4, wherein,

a plurality of holes are provided on the second member and are circumferentially spaced apart from the sink region; the number of holes on the second member is smaller than the number of holes on the first member, and the number of recesses on the second member is the same as the number of recesses on the first member.

7. The stator core as claimed in claim 6, wherein,

the plurality of holes on the first member and the plurality of holes on the second member form a plurality of flow passages in the axial direction, and the holes forming each flow passage are staggered in the axial direction.

8. The stator core according to any one of claim 1 to 3, wherein,

the outer periphery of the protruding portion of the third member has a first diameter.

9. An electric machine, characterized in that the electric machine has a housing and a stator core according to any one of claims 1-8.

10. An electric drive system having at least one of a decelerator and an inverter, and the motor of claim 9.