CN217036849U

CN217036849U - Stator punching sheet, stator core, outer rotor hub motor and electric vehicle

Info

Publication number: CN217036849U
Application number: CN202220428222.3U
Authority: CN
Inventors: 周倩云; 孙重阳; 左亚军; 刘海量
Original assignee: Guangdong Welling Motor Manufacturing Co Ltd; Welling Wuhu Motor Manufacturing Co Ltd
Current assignee: Guangdong Welling Motor Manufacturing Co Ltd; Welling Wuhu Motor Manufacturing Co Ltd
Priority date: 2022-02-28
Filing date: 2022-02-28
Publication date: 2022-07-22
Anticipated expiration: 2032-02-28

Abstract

The utility model discloses a stator punching sheet, a stator core, an outer rotor hub motor and an electric vehicle, wherein the stator punching sheet comprises a stator yoke part and a plurality of straight tooth parts, the straight tooth parts are positioned at the radial outer side of the stator yoke part, the plurality of straight tooth parts are uniformly distributed in the circumferential direction, n grooves are arranged on the end surfaces of the straight tooth parts, the width of each straight tooth part is Bs1 along the circumferential direction of the stator yoke part, and the width of each groove is Bf1, so that the requirements that: 0.75 Bs1/(2n +1) ≦ Bf1 ≦ 1.25 Bs1/(2n +1), wherein units of Bs1 and Bf1 are mm, and n is an integer of 1 or more. The utilization rate of the material can be greatly improved, and the cost is reduced; the torque pulsation of the motor can be reduced, the noise can be reduced, and the performance of the motor can be improved.

Description

Stator punching sheet, stator core, outer rotor hub motor and electric vehicle

Technical Field

The utility model relates to the technical field of motors, in particular to a stator punching sheet, a stator core, an outer rotor hub motor and an electric vehicle.

Background

In the related technology, in an external rotor motor, the stator punching sheet for manufacturing the stator core has the problems of low material utilization rate, high silicon steel waste rate and the like, at present, a wound core is generally adopted for the stator core of the external rotor motor, the material utilization rate can be improved to a certain extent, but the stator punching sheet has tooth shoes, the material utilization rate can only reach about 70% at most, and if a straight tooth structure without the tooth shoes is adopted, the problems of large torque pulsation, high noise and the like of the motor are caused due to the obvious tooth space effect.

SUMMERY OF THE UTILITY MODEL

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the stator punching sheet provided by the utility model can effectively improve the material utilization rate and reduce the torque pulsation and the noise.

The utility model also provides a stator core adopting the stator punching sheet.

The utility model also provides an outer rotor hub motor adopting the stator core and an electric vehicle adopting the outer rotor hub motor.

According to the stator punching sheet of the embodiment of the first aspect of the utility model, the stator punching sheet comprises a stator yoke part and a plurality of straight tooth parts, the straight tooth parts are positioned at the radial outer side of the stator yoke part, the straight tooth parts are uniformly distributed in the circumferential direction, n grooves are arranged on the end surfaces of the straight tooth parts, the width of each straight tooth part in the circumferential direction of the stator yoke part is Bs1, the width of each groove is Bf1, and the following requirements are met: 0.75 Bs1/(2n +1) ≦ Bf1 ≦ 1.25 Bs1/(2n +1), wherein units of Bs1 and Bf1 are mm, and n is an integer of 1 or more.

The stator punching sheet provided by the embodiment of the first aspect of the utility model at least has the following beneficial effects: the stator punching sheet consists of a stator yoke part and a plurality of straight tooth parts, and double rows of straight tooth parts are arranged oppositely in the discharging and blanking process, so that the utilization rate of materials can be greatly improved, and the cost is reduced; the end face of the straight tooth part is provided with n grooves, the width of the straight tooth part is Bs1, the width of each groove is Bf1, the design limit is 0.75 × Bs1/(2n +1) ≦ Bf1 ≦ 1.25 × Bs1/(2n +1), torque pulsation of the motor can be reduced, noise is reduced, and the performance of the motor is improved.

According to some embodiments of the first aspect of the utility model, the Bs1 and the Bf1 satisfy: bf1 ═ Bs1/(2n + 1).

According to some embodiments of the first aspect of the present invention, the n is an even number greater than 1.

According to some embodiments of the first aspect of the present invention, a stator slot is formed between two adjacent straight tooth portions, and a width of the stator slot along a circumferential direction of the stator yoke portion is L, and satisfies: L-Bs1 is more than or equal to 1mm, wherein the unit of L is mm.

According to some embodiments of the first aspect of the present invention, the L and the Bs1 further satisfy: L-Bs1 is less than or equal to 3 mm.

According to some embodiments of the first aspect of the present invention, the bottom wall of the groove is an arc-shaped surface, and the arc-shaped surface is connected with the side wall of the groove.

According to some embodiments of the first aspect of the present invention, the bottom wall of the groove is planar, and a chamfer is provided between the bottom wall and the side wall of the groove.

According to the stator core of the second aspect of the utility model, the stator punching sheets are wound into a ring shape, the straight teeth are arranged on the periphery of the yoke portion of the stator, and then the stator punching sheets are laminated into a whole.

The external rotor hub motor according to the third aspect of the utility model comprises the stator core according to the second aspect of the utility model.

According to the embodiment of the fourth aspect of the utility model, the electric vehicle comprises the outer rotor hub motor.

Additional aspects and advantages of the utility model will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the utility model.

Drawings

Additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic structural diagram of a stator lamination according to an embodiment of the first aspect of the present invention;

FIG. 2 is a schematic view of a partially straight tooth structure according to some embodiments of the first aspect of the present invention;

FIG. 3 is a schematic view of a partial straight tooth structure in another embodiment of the first aspect of the present invention;

fig. 4 is a front view of a stator punching sheet blanking according to an embodiment of the first aspect of the present invention;

fig. 5 is a schematic diagram of a blanking layout of a stator punching sheet according to an embodiment of the first aspect of the present invention;

fig. 6 is a schematic structural view of a stator core according to an embodiment of the second aspect of the present invention;

fig. 7 is a schematic structural view of a part of a stator assembly in an external rotor hub motor according to a third embodiment of the present invention;

fig. 8 is a graph of torque ripple as a function of groove width.

The reference numbers are as follows:

the stator punching sheet 100, the stator yoke portion 110, the straight tooth portion 120, the groove 121 and the stator slot 130;

stator core 200, straight teeth 210, and strip-shaped grooves 211;

stator assembly 300, windings 310, stator support 320.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

In the description of the present invention, it should be understood that the orientation or positional relationship referred to in the description of the orientation, such as the upper, lower, front, rear, left, right, etc., is based on the orientation or positional relationship shown in the drawings, and is only for convenience of description and simplification of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, if there are first and second described only for the purpose of distinguishing technical features, it is not understood that relative importance is indicated or implied or that the number of indicated technical features or the precedence of the indicated technical features is implicitly indicated or implied.

In the description of the present invention, unless otherwise explicitly limited, terms such as arrangement, installation, connection and the like should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above terms in the present invention in combination with the specific contents of the technical solutions.

As shown in fig. 1 to 5, an embodiment of the first aspect of the present invention provides a stator lamination, which is mainly applied to a stator assembly 300 of an outer rotor hub motor, but may also be applied to other types of outer rotor motors, and is described below by taking an outer rotor hub motor as an example. The stator punching sheet 100 comprises a stator yoke portion 110 and straight tooth portions 120, the number of the straight tooth portions 120 is set according to the actual size and requirements of the stator assembly, generally, the number of the straight tooth portions 120 is a double number and is more than or equal to twelve, and the plurality of the straight tooth portions 120 are uniformly distributed along the circumferential direction of the stator yoke portion 110 and are distributed on the radial outer side of the stator yoke portion 110. It can be understood that, in the process of manufacturing the stator punching sheet 100, as shown in fig. 5, the discharging manner adopts a double-row structure, that is, the straight teeth portions 120 of the two stator punching sheets 100 are oppositely arranged and are distributed in a staggered manner, and because the straight teeth portions 120 do not have tooth shoes, the gap of the double-row discharging manner is small, after the stator punching sheet 100 is punched and formed, the punching excess stock is greatly reduced, the utilization rate of silicon steel materials is effectively improved, and the cost is reduced.

It can be understood that, because a straight tooth structure without a tooth shoe is adopted, a cogging effect is caused, so that the torque ripple of the external rotor hub motor is large, the noise is large, and generally the torque ripple of the external rotor hub motor can reach more than 10%. In order to improve the above-mentioned defects, n grooves 121 are opened in the end surface of the straight tooth portion 120, where n is an integer equal to or greater than 1, the radial direction of the stator yoke portion 110 is set to the longitudinal direction of the straight tooth portion 120, the circumferential direction of the stator yoke portion 110 is set to the width direction of the straight tooth portion 120, the width of the straight tooth portion 120 is defined as Bs1, the width of the groove 121 is defined as Bf1, and the following formula is satisfied in design: 0.75 × Bs1/(2n +1) ≦ Bf1 ≦ 1.25 × Bs1/(2n +1), where the units of Bs1 and Bf1 are mm. The n grooves 121 are arranged on the end face of the straight tooth part 120, the width of the straight tooth part 120 and the width of the grooves 121 are limited to 0.75 Bs1/(2n +1) to Bf1 to 1.25 Bs1/(2n +1) in design, so that the torque pulsation and noise of the external rotor hub motor can be reduced, and the performance of the external rotor hub motor is improved.

It is understood that the following table 1 is a data table of torque ripple according to the width (Bf1) of the groove 121 under the condition that the width (Bs1) of the spur portion 120 takes 10 mm.

From table 1, a graph as shown in fig. 8 can be obtained, and from the graph of fig. 8, when the width (Bs1) of the straight tooth portion 120 is 10mm and the width (Bf1) of the groove 121 is 2mm, a nearly minimum torque ripple can be obtained, and when the value of n is 2, the torque ripple is in a lower range in the value range corresponding to Bf1 of 1.5 to 2.5 according to the above formula 0.75 Bs1/(2n +1) ≦ Bf1 ≦ 1.25 Bs1/(2n + 1); when Bf1 is 1 × Bs1/(2 × 2+1) is 0.2Bs1, that is, under the condition that the width (Bs1) of the straight tooth portion 120 is 10mm and the value of n is 2, the width (Bf1) of the groove 121 is 2mm, which can obtain a torque ripple close to the minimum and improve the output torque stability of the outer rotor hub motor, therefore, a preferred embodiment is: bf1 ═ Bs1/(2n + 1).

It can be understood that, in experiments, it is known that, when the value of n is even, a better torque ripple reduction effect can be obtained, and noise reduction is facilitated, as shown in fig. 1, 2 grooves 121 are provided on the end surface of each straight tooth portion 120, and when the width (Bf1) of each groove 121 is 0.2 × the width (Bs1) of the straight tooth portion 120, a nearly minimum torque ripple can be obtained. It should be understood that the even number of the grooves 121 are uniformly spaced on the end surface of the straight tooth portion 120, and the uniformly spaced grooves 121 are beneficial to improving the output torque stability of the outer rotor hub motor during the operation of the outer rotor hub motor. Of course, the non-uniform distribution mode can be adopted, and the stability of the output torque of the outer rotor hub motor is improved.

Referring to fig. 1, it can be understood that there is one stator slot 130 between two adjacent straight teeth 120, the stator slot 130 is used for accommodating the winding 310 of the stator assembly 300, and the width of the stator slot 130 is also defined along the circumferential direction of the stator yoke 110, and the width of the stator slot 130 is defined as L, which satisfies the following design: L-Bs1 is more than or equal to 1mm, wherein the units of L and Bs1 are both mm. Referring to fig. 5, in consideration of manufacturing of the stator laminations 100, a double-row structure is adopted in a discharging mode, that is, the straight tooth parts 120 of the two stator laminations 100 are arranged in a bidirectional mode and staggered, and the requirement that L is greater than Bs1 can ensure that the straight tooth parts 120 cannot interfere with each other, and the design requirement that L-Bs1 is greater than or equal to 1mm is met.

Referring to fig. 5, it should be understood that, further, L and Bs1 are also required to satisfy: L-Bs1 is not more than 3mm, namely, L-Bs1 is not less than 1mm and not more than 3mm, in the discharging process, the gap between two straight tooth parts 120 is set between 1mm and 3mm, under the precondition that the feasibility of the high punching process is ensured, the utilization rate of the silicon steel sheet material is nearly maximized, if the gap is too small, the high punching process cannot meet the precision requirement of punching, and if the gap is too large, the utilization rate of the silicon steel material is reduced. The clearance of two straight tooth portions 120 is set between 1mm and 3mm, and the material utilization rate of silicon steel can reach more than 86%, so that the material utilization rate of silicon steel is greatly improved, and the cost is reduced.

Referring to fig. 2, the groove 121 is provided as an arc-shaped slot, that is, the bottom wall of the groove 121 is an arc-shaped surface, wherein the arc-shaped surface may directly extend to the end surface of the straight tooth portion 120, as shown in fig. 2. In addition, it is also possible that the groove 121 has straight side surfaces, and the side surfaces of the groove 121 are connected to the arc-shaped surfaces.

Referring to fig. 3, the bottom wall of the groove 121 may also be a flat surface, and a chamfer may be provided between the bottom wall and the side wall of the groove 121, and the chamfer may be a rounded corner, as shown in fig. 3, or a right angle. All the structural modes can reduce the torque pulsation of the outer rotor hub motor and reduce noise, and the performance of the outer rotor hub motor is improved.

The stator core 200 according to the embodiment of the second aspect of the present invention is formed by stacking a plurality of stator laminations 100, after the stator laminations 100 are blanked and formed, the stator laminations 100 are wound into a ring shape to obtain an outer shape as shown in fig. 1, a plurality of straight teeth 120 are arranged on the outer periphery of a stator yoke 110, and then the plurality of stator laminations 100 are stacked into an integrated stator core 200 as shown in fig. 6. The stator core 200 has a plurality of straight teeth 210 uniformly distributed in the circumferential direction, and the end faces of the straight teeth 210 form strip-shaped grooves 211 composed of grooves 121, and due to the strip-shaped grooves 211, the stator core 200 can reduce torque pulsation and noise of the outer rotor hub motor, and is beneficial to improving the performance of the outer rotor hub motor.

It can be understood that the external rotor hub motor provided by the embodiment of the third aspect of the present invention includes a central shaft, and a housing assembly, a stator assembly 300, a rotor assembly and a gear assembly connected to the central shaft, wherein the central shaft is connected to a frame of an electric vehicle and serves as a mounting base, the housing assembly includes a main housing, a sub-housing and a rim, the main housing and the sub-housing are respectively disposed at two ends of the rim, the main housing and the sub-housing are fixedly connected to two ends of the rim through screws, three bearings are mounted on the central shaft, and the main housing, the sub-housing and the rotor assembly are respectively connected to one bearing and can rotate relative to the central shaft.

It can be understood that, the gear assembly includes the sun gear, three planet wheel, planet carrier and outer ring gear, sun gear fixed connection is in the rotor subassembly, planet carrier fixed connection axis, three planet wheel rotate to be connected on the planet carrier, outer ring gear fixed connection is in the main casing body, the planet wheel meshes the sun gear simultaneously, outer ring gear, the rotor subassembly drives the sun gear rotatory, the three planet wheel of sun gear drive is rotatory, three planet wheel redriven outer ring gear is rotatory with the main casing body, the main casing body drives the rim rotation, the rim belongs to the wheel of electric motor car, therefore in-wheel motor direct drive wheel rotates, realize going of electric motor car. In addition, the planet wheel is a duplicate gear, two-stage transmission speed reduction is realized through the planet wheel, the rotating speed of the rim is reduced, the output torque of the hub motor is improved, and the speed of the electric vehicle is increased.

It can be understood that the gear assembly is located between rotor assembly and the main casing body, therefore rotor assembly and main casing body cooperation constitute one and seal the fat chamber, and the gear assembly is established at a fat intracavity, seals the fat chamber and holds the gear assembly on the one hand, prevents that the gear assembly from exposing, and on the other hand is holding lubricating grease for the surface of sun gear, three planet wheel and outer ring gear can coat with lubricating grease, provides sufficient lubrication, reduces wearing and tearing.

It can be understood that, when considering sun gear and three planet wheel high speed rotation, because the effect of centrifugal force, can throw away lubricating grease, lead to the lubrication not enough, consequently set up first retaining ring on the rotor subassembly, set up the second retaining ring on the main casing body, first retaining ring is towards the main casing body, the second retaining ring is towards the rotor subassembly, the lateral wall in grease sealing chamber is constituteed to first retaining ring and second retaining ring, play the effect that prevents lubricating grease and leak outward, in centraxonial axial, first retaining ring and second retaining ring are staggered arrangement, can block the lubricating grease that is thrown away, impel lubricating grease to remain in the grease sealing chamber, guarantee that the gear assembly has sufficient lubrication, in centraxonial footpath, first retaining ring and second retaining ring are close to each other and contactless, do not influence rotor subassembly and main casing body respective independent rotation.

Referring to fig. 7, a stator assembly 300 of an outer rotor hub motor includes a stator core 200 according to the embodiment of the second aspect, and a winding 310, a stator bracket 320, and the like, where the winding 210 is mounted on a straight tooth 210 of the stator core 200, and the straight tooth 210 without a tooth shoe means that a side wall of the straight tooth 210 does not have a structure extending outward for limiting the winding 310, so that a limiting frame (not shown in the figure) may be connected to the stator bracket 320, and the limiting frame is used for limiting a radial position of the winding 310 relative to the straight tooth 210 to prevent the winding 310 from slipping off the straight tooth 210.

It should be noted that the connection mode of the limiting frame and the stator bracket 320 may be fixed connection or detachable connection; wherein, the fixed connection can be fixed by welding or riveting; wherein, the detachable connection can adopt a screw or a buckle structure for connection, and the like.

As shown in fig. 6, in some embodiments of the present invention, two opposite side walls of the straight tooth 210 are arranged in parallel, that is, the straight tooth 210 is in a straight tooth shape, and the cross section of the straight tooth 210 is unchanged and in a rectangular shape, which is beneficial to splicing and discharging materials, as shown in fig. 5, silicon steel material can be fully utilized, waste generation is reduced, and utilization rate of the silicon steel material is improved.

In addition, the straight teeth 210 are arranged to be straight teeth, when the winding 310 is wound, the wires can be wound layer by layer, and no special requirements are required for the shapes of the wires, so that the winding device is suitable for the wires with various shapes, the winding process of the winding 310 is facilitated, and unstable factors in the winding process are reduced.

In the above embodiment, the winding 310 may be externally wound by using a tool, and then mounted on the stator core 200, so that the operation space is large, the operation is convenient, and the slot fullness rate can be effectively improved.

It can be understood that the limiting frame is provided with a plurality of limiting parts, the limiting parts correspond to the straight teeth 210 or the windings 310 in number one to one, and the limiting parts are matched with the outer end faces of the windings 310 to prevent the windings 310 from slipping off the straight teeth 210. Every spacing portion includes two parallel arrangement's fork arm, and the interval between two fork arms and straight-tooth 210's width looks adaptation to the fork arm can hold straight-tooth 210, the outer terminal surface butt of fork arm and winding 310, make spacing portion can have two points to act on winding 310, so that stabilize spacing to winding 310.

In addition, in some embodiments, a connecting rod may be further disposed between the two forks, the connecting rod is disposed perpendicular to the forks, and the connecting rod also abuts against the outer end surface of the winding 310, and the connecting rod also limits the winding 310, that is, the limiting portion has three points acting on the winding 310, so as to further improve the stability of limiting the winding 310.

The embodiment of the fourth aspect of the utility model provides an electric vehicle, wherein the electric vehicle adopts the outer rotor hub motor of the embodiment of the third aspect, protects all technical schemes of the outer rotor hub motor, has all technical effects of the outer rotor hub motor, and is not repeated.

The embodiments of the present invention have been described in detail with reference to the drawings, but the present invention is not limited to the embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the gist of the present invention.

Claims

1. Stator punching, its characterized in that includes:

stator yoke portion and a plurality of straight tooth portion, the straight-tooth position in the radial outside of stator yoke portion, it is a plurality of straight tooth portion is the circumference equipartition, the terminal surface of straight tooth portion is provided with a plurality of recesses of n, follows the circumference of stator yoke portion, the width of straight tooth portion is Bs1, the width of recess is Bf1, satisfies: 0.75 × Bs1/(2n + 1). ltoreq.Bf 1.ltoreq.1.25 × Bs1/(2n +1), wherein the units of Bs1 and Bf1 are mm, and n is an integer of 1 or more.

2. The stator lamination as recited in claim 1, wherein the Bs1 and the Bf1 satisfy: bf1 ═ Bs1/(2n + 1).

3. The stator lamination as recited in claim 1, wherein n is an even number greater than 1.

4. The stator punching sheet according to claim 1, wherein a stator slot is formed between two adjacent straight teeth, and along the circumferential direction of the stator yoke portion, the width of the stator slot is L, so that: L-Bs1 is more than or equal to 1mm, wherein the unit of L is mm.

5. The stator lamination as recited in claim 4, wherein the L and the Bs1 further satisfy: L-Bs1 is less than or equal to 3 mm.

6. The stator punching sheet according to claim 1, wherein the bottom wall of the groove is an arc-shaped surface, and the arc-shaped surface is connected with the side wall of the groove.

7. The stator punching sheet according to claim 1, wherein the bottom wall of the groove is a plane, and a chamfer is arranged between the bottom wall and the side wall of the groove.

8. A stator core, characterized by comprising the stator lamination as recited in any one of claims 1 to 7.

9. An external rotor hub motor comprising the stator core according to claim 8.

10. An electric vehicle comprising the external rotor hub motor according to claim 9.