Motor stator punching sheet and motor

Abstract

The invention relates to the technical field of motors, and particularly provides a motor stator punching sheet and a motor, and the motor stator punching sheet comprises a plurality of punching sheet assemblies which are distributed along the circumferential direction of the motor stator punching sheet; the punching sheet assembly comprises a shoe unit, the shoe unit is arranged at one end, close to a motor rotor, of the punching sheet assembly, a matching edge is arranged on one side, close to the motor rotor, of the shoe unit, and the matching edge is of an arc-shaped structure protruding towards the motor rotor. The punching sheet assembly is provided with the matching edge of the arc-shaped structure, so that the air gap between the motor stator and the motor rotor is in a non-uniform state, the magnetic flux density distribution of the air gap is close to a sine wave, and the cogging torque can be reduced.

Description

A motor stator lamination and a motor Technical Field

[0001] This disclosure relates to the field of motor technology, and in particular to a motor stator lamination and a motor. Background Technology

[0002] The stator core of a permanent magnet motor is formed by stacking stator laminations using different processes. The stator core has slots and windings, while the rotor contains permanent magnets. Cogging torque is the torque generated by the interaction between the permanent magnets and the stator core when the windings are not energized; it is caused by the pulsation of the tangential component of the interaction force between the permanent magnets and the stator teeth. When the motor rotor rotates, the magnetic permeability changes significantly within a small range corresponding to the stator slots on both sides of the permanent magnet, causing a change in the stored magnetic field energy, thus generating cogging torque. Cogging torque (cogging force) is a unique problem of permanent magnet motors and a key issue that must be considered and resolved in the design and manufacturing of high-performance permanent magnet motors. Cogging torque causes torque pulsation in the permanent magnet motor, leading to speed fluctuations. Torque pulsation also causes vibration and noise in the motor. When the frequency of the pulsating torque coincides with the armature current resonant frequency, resonance occurs, which inevitably amplifies the vibration and noise of the cogging torque, severely affecting the motor's positioning accuracy and servo performance, especially at low speeds. To reduce motor vibration and noise, more costs are often required. How to reduce the manufacturing cost of motors while ensuring stable performance has become a challenge for companies.

[0003] Traditional methods for overcoming cogging torque include selecting appropriate cogging fits, using closed or small slots, appropriately increasing the air gap, employing rotor skew, and using rotor eccentricity, among other common methods for suppressing positioning torque. However, all these methods increase motor leakage flux, decrease air gap magnetic flux density, and reduce motor material utilization, sacrificing motor power and performance. In engineering applications, achieving ideal cogging positioning torque often involves a combination of methods, resulting in complex processes, high costs, and negative impacts on motor output performance. In particular, with the emergence of permanent magnet synchronous flat wire motors operating at increasingly higher speeds, the impact of cogging torque becomes more pronounced with increasing speed. Therefore, suppressing positioning torque has become a significant challenge in the design and manufacturing of permanent magnet motors. Summary of the Invention

[0004] This disclosure is made in view of the above-mentioned problems. This disclosure provides a motor stator lamination and a motor.

[0005] According to one aspect of this disclosure, a motor stator lamination is provided, comprising: for assembling a motor stator, characterized in that it comprises: a plurality of lamination assemblies, the plurality of lamination assemblies being distributed circumferentially along the motor stator lamination; each lamination assembly includes a shoe unit disposed at one end of the lamination assembly near the motor rotor, the shoe unit having a mating edge on the side near the motor rotor, the mating edge being configured as an arcuate structure convex toward the motor rotor.

[0006] Furthermore, according to one aspect of this disclosure, the mathematical model of the mating edge is an Archimedean spiral, and the center of the arcuate structure of the mating edge may or may not coincide with the center of the motor rotor along the axial direction.

[0007] Furthermore, according to one aspect of this disclosure, when the center of the mating edge coincides with the center of the motor rotor, the radius of the formed Archimedean spiral is ρ and the angle is θ, which can be expressed using polar coordinate equations as ρ=a+bθ.

[0008] Furthermore, according to one aspect of the present disclosure, the stator lamination of a motor includes a shoe unit comprising a first shoe unit and a second shoe unit, the first shoe unit and the second shoe unit being symmetrically arranged along the radial centerline of the lamination assembly, the first shoe unit protruding toward a first side of the lamination assembly, and the second shoe unit protruding toward a second side of the lamination assembly.

[0009] Furthermore, according to one aspect of the present disclosure, the mating edge of the motor stator lamination is composed of a first edge located in the first shoe unit and a second edge located in the second shoe unit, wherein the mathematical model of the first edge and the second edge is two symmetrically arranged Archimedean spirals.

[0010] Furthermore, according to one aspect of the present disclosure, the motor stator lamination assembly further includes a yoke unit disposed at one end of the lamination assembly away from the motor rotor, and the yoke units of a plurality of the lamination assemblies can be combined to form a ring structure.

[0011] Furthermore, according to one aspect of this disclosure, a motor stator lamination has a first connecting device on a first side and a second connecting device on a second side, and adjacent lamination assemblies are connected and combined via the first connecting device and the second connecting device; one of the first connecting device and the second connecting device is a connecting protrusion and the other is a connecting groove.

[0012] Furthermore, according to one aspect of the present disclosure, in a motor stator lamination, after the first connecting device and the second connecting device are combined, through holes distributed along the thickness direction of the lamination assembly are formed at the connecting position.

[0013] Furthermore, according to one aspect of the present disclosure, the motor stator lamination assembly further includes: a toothed unit disposed between the shoe unit and the yoke unit, a first end of the toothed unit being connected to the yoke unit and a second end being connected to the shoe unit, and a winding groove being formed between the toothed units of adjacent lamination assemblies.

[0014] Furthermore, according to one aspect of this disclosure, the motor stator laminations are either manufactured separately or as a single unit.

[0015] According to another aspect of this disclosure, an electric motor is provided, comprising: a motor stator, the motor stator including motor stator laminations as described in any of the preceding claims; and a motor rotor, wherein an air gap is provided between the motor stator and the motor rotor, the width ε of the air gap varying at different positions in the circumferential direction.

[0016] According to an embodiment of this disclosure, a motor stator lamination and a motor are disclosed. By setting an arc-shaped mating edge on the lamination assembly, the air gap between the motor stator and the motor rotor becomes non-uniform, thereby achieving an air gap magnetic flux density distribution close to a sine wave. This is beneficial for reducing cogging torque and effectively suppressing it. Furthermore, the arc-shaped mating edge reduces the cogging period, resulting in a more significant reduction in cogging torque. Additionally, it simplifies the structure of the shoe unit, lowers the precision requirements for mold dimensions in this part, and thus simplifies the processing technology, effectively saving manufacturing costs for the motor stator lamination. Attached Figure Description

[0017] The above and other objects, features, and advantages of this disclosure will become more apparent from the more detailed description of the embodiments thereof in conjunction with the accompanying drawings. The drawings are provided to further illustrate the embodiments of this disclosure and form part of the specification. They are used in conjunction with the embodiments of this disclosure to explain the disclosure and do not constitute a limitation thereof. In the drawings, the same reference numerals generally represent the same components or steps.

[0018] Figure 1 is a structural schematic diagram of a single lamination assembly according to an embodiment of the present disclosure; Figure 2 is a structural schematic diagram of a combination of multiple lamination assemblies according to an embodiment of the present disclosure; Figure 3 is a cross-sectional structural schematic diagram of a motor according to an embodiment of the present disclosure; Figure 4 is a structural schematic diagram of the air gap between the motor stator and the motor rotor according to an embodiment of the present disclosure; Figure 5 is a dimensional schematic diagram of a single lamination assembly according to an embodiment of the present disclosure; Figure 6 is a dimensional schematic diagram of a single lamination assembly according to an embodiment of the present disclosure.

[0019] Explanation of reference numerals in the attached drawings: 1. Motor stator; 2. Winding slot; 3. Motor rotor; 4. Motor; 5. Lamination assembly; 10. Yoke unit; 11. Connecting protrusion; 12. Connecting groove; 13. Shoe unit; 14. First shoe unit; 15. Second shoe unit; 16. Tooth unit; 17. Mating edge; 18. First edge; 19. Second edge; 20. Through hole; 21. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this disclosure more apparent, exemplary embodiments according to this disclosure will now be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this disclosure, and not all embodiments of this disclosure. It should be understood that this disclosure is not limited to the exemplary embodiments described herein.

[0021] This disclosure provides a motor stator lamination and a motor. By setting an arc-shaped mating edge on the lamination assembly, the air gap between the motor stator and the motor rotor is made non-uniform, thereby achieving an air gap magnetic flux density distribution close to a sine wave, which is beneficial to reducing cogging torque.

[0022] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings.

[0023] As shown in Figures 1, 2, and 3, this embodiment of the present disclosure provides a motor stator lamination for assembling a motor stator 1, including: a plurality of lamination assemblies 10; the material of the lamination assembly 10 is typically silicon steel. Multiple lamination assemblies 10 are distributed circumferentially along the motor stator laminations to form an annular motor stator lamination. Multiple annular motor stator laminations are stacked and combined axially to form the motor stator 1, also known as the stator core. Alternatively, multiple lamination assemblies 10 can be stacked and combined axially to form stator blocks, and then multiple stator blocks can be stacked circumferentially to form the motor stator 1. The lamination assembly 10 includes a shoe unit 14, which is located at one end of the lamination assembly 10 near the motor rotor 4. This end is located in the inner ring of the motor stator lamination. The shoe unit 14 has a mating edge 18 on the side near the motor rotor 4. The mating edge 18 is an arc-shaped structure protruding towards the motor rotor 4. The mathematical model of this arc-shaped structure can be of various types, such as a part of a circle, a part of a parabola, or a part of an Archimedean spiral, etc.

[0024] Because the mating edge 18 is an arc-shaped structure protruding towards the motor rotor 4, when the motor rotor 4 and the motor stator 1 rotate relative to each other, the air gap width ε between the motor rotor 4 and the shoe unit 14 is in a continuously changing state, and the air gap is in a non-uniform state, as shown in Figure 4. This achieves the goal of making the air gap magnetic flux density distribution close to a sine wave, which is beneficial to reducing the cogging torque.

[0025] In some possible implementations, the mathematical model of the mating edge 18 is an Archimedean spiral, and the shape of the mating edge 18 is a part of an Archimedean spiral. The center of the arc structure of the mating edge 18 may or may not coincide with the center of the motor rotor 4 along the axial direction. Both structures can achieve a continuously changing air gap width ε. The actual structure used is related to the size of the motor. During the design of each motor, several sets of comparative schemes with and without coincident centers are selected. The suppression effect of cogging torque and the amount of material used are analyzed and compared to comprehensively evaluate the options, and finally, the most suitable scheme is selected.

[0026] In some possible implementations, as shown in Figures 5 and 6, when the center of the mating edge 18 coincides with the center of the motor rotor 4, the radius of the formed Archimedean spiral is ρ and the angle is θ, which can be expressed using polar coordinate equations as ρ = a + bθ.

[0027] Where a and b are real numbers, controlling the initial radius and pitch of the helix, respectively. When θ=0, a is the distance from the starting point to the origin of the polar coordinates. dρ / dθ=b, where b is the increase in angle ρ for each unit increase in the helix. When θ>0, a is equivalent to a rotating helix, while parameter b controls the distance between two adjacent curves.

[0028] In some possible implementations, as shown in Figures 1 and 2, the boot unit 14 includes a first boot unit 15 and a second boot unit 16. The first boot unit 15 and the second boot unit 16 are symmetrically arranged along the radial centerline of the lamination assembly 10. The first boot unit 15 protrudes towards a first side of the lamination assembly 10, and the second boot unit 16 protrudes towards a second side of the lamination assembly 10. The ends of both the first boot unit 15 and the second boot unit 16 are pointed.

[0029] The first boot unit 15 and the second boot unit 16 are symmetrically arranged, so that the manufacturing process of the left and right sides of the stamping assembly 10 is uniform, and its shape is uniform and balanced, which makes it easy to ensure the processing accuracy and structural strength.

[0030] In some possible implementations, as shown in Figures 5 and 6, the mating edge 18 is composed of a first edge 19 located in the first boot unit 15 and a second edge 20 located in the second boot unit 16. The mathematical model of the first edge 19 and the second edge 20 is two symmetrically arranged Archimedean spirals. The two Archimedean spirals have the same radius and angle, but different directions of development, and have positive and negative values.

[0031] In some possible implementations, as shown in Figures 1 and 2, the lamination assembly 10 further includes a yoke unit 11, which is disposed at one end of the lamination assembly 10 away from the motor rotor 4, and multiple yoke units 11 of the lamination assembly 10 can be combined into a ring structure.

[0032] The outline of the yoke unit 11 can be a standard arc shape, but it is not limited to a standard arc shape, that is, it is not limited to a standard ring shape. The yoke unit 11 can also have structures such as protrusions and depressions on the basis of a standard arc shape. Although the outline of the yoke unit 11 is not a standard arc shape, the structure formed by the yoke units 11 after multiple stamping assemblies 10 are spliced ​​and combined is also a ring structure.

[0033] In some possible implementations, as shown in Figures 1 and 2, a first connecting device is provided on the first side (left side in Figure 1) of the yoke unit 11, and a second connecting device is provided on the second side (right side in Figure 1). Adjacent lamination assemblies 10 are connected and assembled through the first connecting device and the second connecting device. The first connecting device and the second connecting device are designed to correspond to each other in terms of structure, size, position, and other features. This design can improve the accuracy of the lamination assembly 10 and also eliminate the damage and precision loss caused by welding and fixing adjacent stator blocks.

[0034] In some possible implementations, as shown in Figures 1 and 2, one of the first connecting device and the second connecting device is a connecting protrusion 12, and the other is a connecting groove 13. The connecting protrusion 12 needs to move in and out of the connecting groove 13 axially. After the connecting protrusion 12 is embedded in the connecting groove 13, it cannot be withdrawn circumferentially, thereby realizing the combination between adjacent lamination assemblies 10.

[0035] As shown in Figures 1 and 2, the connecting protrusion 12 protrudes outward from the first side of the yoke unit 11 and may have multiple regular or irregular arc-shaped solid areas. The connecting groove 13 is recessed inward from the second side of the yoke unit 11 and has multiple regular or irregular arc-shaped hole areas. In this way, after the connecting protrusion 12 is embedded in the connecting groove 13, it can have a backstop function.

[0036] In some possible implementations, as shown in Figures 1 and 2, after the first connecting device and the second connecting device are combined, through holes 21 distributed along the thickness direction of the lamination assembly 10 are formed at the connection position, which can reduce hysteresis loss. The through holes 21 can be separately provided on the connecting protrusion 12 and the connecting groove 13. The through holes 21 can be formed by inserting the connecting protrusion 12 into the connecting groove 13.

[0037] In some possible implementations, as shown in Figures 1 and 2, the lamination assembly 10 further includes a toothed unit 17, which is disposed between the boot unit 14 and the yoke unit 11. The first end of the toothed unit 17 is connected to the yoke unit 11, and the second end is connected to the boot unit 14. A winding groove 2 is formed between the toothed units 17 of adjacent lamination assemblies 10, and the winding groove 2 is used to accommodate the winding 3.

[0038] The yoke unit 11, the tooth unit 17 and the boot unit 14 are combined to form a winding region. The winding groove 2 is the main component of the winding region. The winding 3 is disposed on the tooth unit 17 and is contained in the winding region.

[0039] Because multiple lamination assemblies 10 need to be assembled into a ring, the width of the end of the toothed unit 17 connecting to the yoke unit 11 is greater than the width of the end connecting to the boot unit 14, and the width gradually changes. As shown in Figure 6, the heights A1 and A2 on the left and right sides of the toothed unit 17 are equal. The yoke unit 11, the toothed unit 17, and the boot unit 14 are integrally formed into an H-shaped structure. This design ensures that the multiple lamination assemblies 10 are firmly joined together, resulting in high reliability.

[0040] In some possible implementations, as shown in Figures 1 and 2, the multiple stamping assemblies 10 are formed separately or as a whole, typically using a stamping process.

[0041] Multiple lamination assemblies 10 are preferably manufactured separately and then assembled to form motor stator laminations. This design offers good manufacturing flexibility and controllable manufacturing costs. The separate motor stator 1 can significantly reduce the manufacturing cost of the motor stator 1. The separate structure makes the size of each lamination assembly smaller and the structure simpler, thus resulting in higher material utilization when cutting from the blank and reducing material waste.

[0042] If a modular structure is adopted, during assembly, the winding can be completed separately on each stator segment before assembling the segments, making the assembly process simpler. Each lamination assembly 10 has a shoe unit 14, and each stator segment has a toothed shoe. During winding, only a single toothed shoe needs to be wound, without any obstruction from other structures, making it even simpler.

[0043] Multiple lamination assemblies 10 can also be manufactured as a whole. Multiple lamination assemblies 10 are integrally fixedly connected on the motor stator laminations. Multiple motor stator laminations are stacked and combined along the axial direction to form the motor stator 1.

[0044] As shown in Figures 3 and 4, this embodiment of the present disclosure also provides a motor 5, specifically an electric motor, including: a motor stator 1 and a motor rotor 4; the motor stator 1 includes the motor stator laminations described in any of the above embodiments, and the motor stator 1 has a hollow inner circular region in the middle; the motor rotor 4 is disposed in the hollow inner circular region of the motor stator 1, and there is an air gap between the motor stator 1 and the motor rotor 4. The width ε of the air gap changes at different positions in the circumferential direction, forming an irregular ring structure at the tooth groove. The uneven air gap width ε is beneficial to reduce the tooth groove torque, reduce the distortion rate of back EMF, and reduce the vibration and noise of the motor.

[0045] It should be noted that the number of pole slots in the motor in this embodiment is not limited to the example shown in the figure. The motor stator laminations and motor stator 1 in this embodiment can be applied to motors with various numbers of pole slots. In addition, the thickness, specific shape, and material of the motor stator laminations are not limited in this embodiment, and can be selected according to requirements in actual applications.

[0046] The above description, with reference to the accompanying drawings, illustrates an embodiment of a motor stator lamination and a motor according to this disclosure. It offers the following advantages: By providing an arc-shaped mating edge on the lamination assembly, the air gap between the motor stator and rotor becomes non-uniform, thereby achieving an air gap magnetic flux density distribution close to a sine wave. This is beneficial for reducing cogging torque and effectively suppressing it. Furthermore, the arc-shaped mating edge reduces the cogging period, resulting in a more significant reduction in cogging torque. Additionally, it simplifies the structure of the shoe unit, lowering the precision requirements for mold dimensions in this part, thus simplifying the processing technology and effectively saving manufacturing costs for the motor stator lamination.

[0047] The basic principles of this disclosure have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this disclosure are merely examples and not limitations, and should not be considered as essential features of each embodiment of this disclosure. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the scope of this disclosure to the necessity of employing the aforementioned specific details for implementation.

[0048] The block diagrams of devices, apparatuses, devices, and systems disclosed herein are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, apparatuses, devices, and systems can be connected, arranged, and configured in any manner. Words such as “comprising,” “including,” “having,” etc., are open-ended terms meaning “including but not limited to,” and are used interchangeably with them. The terms “or” and “and” as used herein refer to the terms “and / or,” and are used interchangeably with them unless the context clearly indicates otherwise. The term “such as” as used herein refers to the phrase “such as but not limited to,” and is used interchangeably with it.

[0049] Additionally, as used herein, the "or" used in a list of items beginning with "at least one" indicates a separate list, such that a list of, for example, "at least one of A, B, or C" means A or B or C, or AB or AC or BC, or ABC (i.e., A and B and C). Furthermore, the word "exemplary" does not imply that the described example is preferred or better than other examples.

[0050] It should also be noted that in the systems and methods of this disclosure, the components or steps can be decomposed and / or recombined. These decompositions and / or recombinations should be considered as equivalent solutions to this disclosure.

[0051] Various changes, substitutions, and modifications can be made to the technology described herein without departing from the teachings defined by the appended claims. Furthermore, the scope of the claims of this disclosure is not limited to the specific aspects of the processes, machines, manufactures, events, means, methods, and actions described above. Currently existing or later-developed processes, machines, manufactures, events, means, methods, or actions that perform substantially the same function or achieve substantially the same result as the corresponding aspects described herein can be utilized. Therefore, the appended claims include such processes, machines, manufactures, events, means, methods, or actions within their scope.

[0052] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use this disclosure. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of this disclosure. Therefore, this disclosure is not intended to be limited to the aspects shown herein, but rather to be carried out within the widest scope consistent with the principles and novel features disclosed herein.

[0053] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this disclosure to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations therein.

Claims

1. A motor stator lamination for assembling a motor stator (1), characterized in that, include: Multiple lamination assemblies (10) are distributed circumferentially along the stator laminations of the motor. Each lamination assembly (10) includes a shoe unit (14) located at one end of the lamination assembly (10) near the motor rotor (4). The shoe unit (14) has a mating edge (18) on the side near the motor rotor (4). The mating edge (18) is an arc-shaped structure protruding toward the motor rotor (4).

2. The motor stator lamination according to claim 1, characterized in that, The mathematical model of the mating edge (18) is an Archimedean spiral. The center of the arc structure of the mating edge (18) may or may not coincide with the center of the motor rotor (4) along the axial direction.

3. The motor stator lamination according to claim 2, characterized in that, When the center of the mating edge (18) coincides with the center of the motor rotor (4), the radius of the formed Archimedean spiral is ρ and the angle is θ, which can be expressed as ρ=a+bθ using polar coordinate equation.

4. The motor stator lamination according to claim 1, characterized in that, The boot unit (14) includes a first boot unit (15) and a second boot unit (16). The first boot unit (15) and the second boot unit (16) are symmetrically arranged along the radial centerline of the stamping assembly (10). The first boot unit (15) protrudes toward a first side of the stamping assembly (10), and the second boot unit (16) protrudes toward a second side of the stamping assembly (10).

5. The motor stator lamination according to claim 4, characterized in that, The mating edge (18) is composed of the first edge (19) of the first boot unit (15) and the second edge (20) of the second boot unit (16). The mathematical model of the first edge (19) and the second edge (20) is two Archimedean spirals arranged symmetrically.

6. The motor stator lamination according to claim 1, characterized in that, The lamination assembly (10) further includes a yoke unit (11), which is disposed at one end of the lamination assembly (10) away from the motor rotor (4), and the yoke units (11) of multiple lamination assemblies (10) can be combined into a ring structure.

7. The motor stator lamination according to claim 6, characterized in that, The first side of the yoke unit (11) is provided with a first connecting device, and the second side is provided with a second connecting device. The adjacent lamination assembly (10) is connected and combined with the second connecting device through the first connecting device. One of the first connecting device and the second connecting device is a connecting protrusion (12), and the other is a connecting groove (13).

8. The motor stator lamination according to claim 6, characterized in that, The lamination assembly (10) further includes a toothed unit (17), which is disposed between the boot unit (14) and the yoke unit (11). The first end of the toothed unit (17) is connected to the yoke unit (11), and the second end is connected to the boot unit (14). A winding groove (2) is formed between the toothed units (17) of adjacent lamination assemblies (10).

9. The motor stator lamination according to any one of claims 1-8, characterized in that, The multiple lamination assemblies (10) are either manufactured separately or as a whole.

10. An electric motor, characterized in that, include: Motor stator (1), wherein the motor stator (1) comprises the motor stator lamination as described in any one of claims 1-9; The motor rotor (4) has an air gap between the motor stator (1) and the motor rotor (4), and the width ε of the air gap changes at different positions in the circumferential direction.

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