A method for processing a motor stator and a motor stator

Abstract

The application discloses a motor stator processing method and motor stator, and relates to the technical field of motors, and comprises the following steps: calculating the expected circumferential magnetostriction elongation of the annular core based on the magnetostriction characteristic parameters of the selected silicon steel sheet; designing the matching geometry and size of the first protrusion on each tooth side of the motor winding and the first groove on the other side according to the magnetostriction elongation; sequentially connecting multiple teeth to form an initial structure main body; limiting and fixing the initial structure main body through positioning tooling and limiting tooling to form an annular structure main body in a pre-tightening state; sleeving the annular structure main body in the welding tooling to form a welding seam between the adjacent teeth of the initial structure main body; and performing glue pouring treatment on the overall structure after welding and fixing, and forming a motor stator finished product after solidification. The application adjusts the splicing structure of the adjacent teeth in combination with the magnetostriction characteristics of the silicon steel sheet, and is beneficial to improving the stability and reliability of the motor stator.

Description

Technical Field

[0001] This invention relates to the field of motor technology, specifically to a method for processing a motor stator and a motor stator. Background Technology

[0002] This section provides only background information related to this application to enable those skilled in the art to understand this application more thoroughly and accurately, and it is not necessarily prior art.

[0003] The existing stator design uses dovetail grooves between each tooth to fix and fit adjacent teeth together. This requires inserting the teeth along their length, winding each tooth sequentially, and then welding to achieve electrical connections between the windings. This makes stator winding cumbersome, and the multiple welded structures result in uneven magnetic circuit distribution in the winding structure, impedance mismatch between phases, and localized overheating in the stator. The dovetail groove insertion method, where adjacent teeth are connected by a splicing structure, causes changes in the localized air gap between the stator and rotor due to the magnetostriction of the silicon steel sheets after splicing and during subsequent processes. This affects the motor's positioning force and cannot meet the requirements of ultra-precision machining. Summary of the Invention

[0004] This invention aims to solve at least one of the technical problems existing in the prior art, and proposes a method for processing a motor stator and a motor stator. By using multiple silicon steel sheets stacked together to form teeth, the winding process of the motor stator can be simplified, the resistance consistency of each tooth of the motor stator can be improved, thereby improving the production efficiency of the motor stator. By combining the magnetostrictive properties of silicon steel sheets to adjust the splicing structure of adjacent teeth, the stability and reliability of the overall structure of the motor stator can be improved.

[0005] This invention proposes a method for processing an electric motor stator, the method comprising:

[0006] S1. Based on the magnetostrictive characteristic parameters of the selected silicon steel sheet and the simulation results of the rated working magnetic flux density of the target motor, the expected circumferential magnetostrictive elongation of the toroidal core is calculated.

[0007] S2. Based on the magnetostrictive elongation, design the mating geometry and size of the first protrusion on the side of each tooth of the motor winding and the first groove on the other side, and form a preload displacement that is coordinated with the direction of the magnetostrictive elongation at the mating interface of the first protrusion and the first groove formed by any two adjacent teeth.

[0008] S3. Multiple teeth are sequentially connected through the engagement of the first protrusion and the first groove to form an initial structural body. A winding machine is used to continuously wind the wire through the multiple teeth of the initial structural body to form a continuous coil on the initial structural body.

[0009] S4. The initial structural body is fixed by positioning and limiting fixtures, and a pre-tightening displacement is applied to each mating position during the limiting process to form a ring-shaped structural body in a pre-tightened state.

[0010] S5. The annular structure body is fitted into the welding fixture, and a local energy-concentrated welding method is used to weld along the tooth length direction in the yoke region to form a weld between adjacent teeth of the initial structure body.

[0011] S6. After welding and fixing, the overall structure is potted with glue, and after curing, it forms the finished motor stator.

[0012] Furthermore, S1 includes:

[0013] Based on the magnetostrictive characteristic parameters of the selected silicon steel sheet and the simulation results of the rated working magnetic flux density of the target motor, the expected circumferential magnetostrictive elongation of the ring structure under the rated working magnetic flux density is determined.

[0014] Based on the expected circumferential magnetostrictive elongation, the mating geometry parameters of the first protrusion and the first groove are designed, and a preload displacement matching the expected circumferential magnetostrictive elongation is formed at the mating position of the first protrusion and the first groove.

[0015] Furthermore, step S1 also includes:

[0016] S11. Based on the material of the silicon steel sheet, find the magnetostrictive strain curve of the silicon steel sheet as a function of magnetic flux density.

[0017] S12. Based on the magnetostrictive strain curve, establish the electromagnetic field finite element analysis model of the target motor and perform simulation processing to obtain the magnetic field strength and direction distribution inside the silicon steel sheet of the tooth section of the motor stator under actual working conditions.

[0018] S13. Combine the magnetic field strength and direction distribution inside the toothed silicon steel sheet with the magnetic hysteresis strain of the toothed silicon steel sheet for composite calculation, and perform integral calculation on the core volume of the target motor to obtain the expected circumferential magnetostrictive elongation of the annular core.

[0019] Furthermore, S4 includes:

[0020] A positioning fixture is formed based on a first limiting part with a columnar structure and a second limiting part with a ring structure, and the spliced ​​ring structure body is fitted onto the first limiting part of the positioning fixture.

[0021] A limiting fixture based on several splicing parts forming a cylindrical structure is fitted onto the outside of the annular structure body, and the limiting parts of the limiting fixture press the annular structure body together.

[0022] Furthermore, S5 includes:

[0023] After the positioning and limiting fixtures are assembled, the main ring structure is fitted into the welding fixture.

[0024] The welding end of the driving welding equipment performs welding operations on the main body of the annular structure along a preset welding path.

[0025] Furthermore, S6 includes: applying a high thermal conductivity insulating adhesive and a high strength structural adhesive to the welded and fixed overall structure for a first-time potting process, which cures to form the finished motor stator.

[0026] The present invention also provides a motor stator, which is prepared based on the processing method of the motor stator, the motor stator comprising:

[0027] The main body of the ring structure is formed by multiple teeth arranged circumferentially and a continuous coil wound on the teeth, each of the teeth being made of multiple layers of mutually insulated silicon steel sheets stacked together;

[0028] Each tooth has an arc-shaped first groove on one side and a first protrusion that matches the first groove on the other side. Adjacent teeth are connected by the engagement of the first protrusion and the first groove.

[0029] The mating structure of the first protrusion and the first groove forms a pre-tightening displacement, the direction of which is the same as the circumferential deformation direction of the silicon steel sheet caused by magnetostriction under the rated working magnetic flux density of the motor.

[0030] Furthermore, any two adjacent teeth of the motor stator are fixedly connected by a weld along the length of the splicing position;

[0031] The splicing position of any two adjacent teeth forms two or more welds.

[0032] Furthermore, the mating surface between the first protrusion and the first groove is provided with a wedge-shaped inclined mating structure, or the mating surface between the first protrusion and the first groove is provided with a micron-sized elastic bulge structure.

[0033] Furthermore, the motor stator also includes a cured adhesive layer encapsulated on the annular structure body and the coil, wherein the cured adhesive layer partially penetrates into the mating interface between adjacent teeth and the weld area.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] By using multiple silicon steel sheets stacked together to form teeth, the winding process of the motor stator can be simplified, the resistance consistency of each tooth of the motor stator can be improved, thereby improving the manufacturing efficiency of the motor stator;

[0036] By combining the magnetostrictive properties of silicon steel sheets with adjustments to the splicing structure of adjacent teeth and with weld seam treatment, the overall rigidity of the motor stator structure is improved, thereby enhancing the stability and reliability of the overall motor stator structure. Attached Figure Description

[0037] Figure 1 This is a flowchart of the processing method for the motor stator in an embodiment of the present invention;

[0038] Figure 2 This is a schematic diagram of the motor stator structure in an embodiment of the present invention;

[0039] Figure 3 This is a schematic diagram of the tooth structure of the motor stator in an embodiment of the present invention;

[0040] Figure 4 This is a flowchart of the method for calculating the magnetostrictive elongation of the silicon steel sheet of the motor stator in an embodiment of the present invention;

[0041] Figure 5 This is a schematic diagram of the positioning fixture for the motor stator in an embodiment of the present invention;

[0042] Figure 6 This is a schematic diagram of the limiting fixture for the motor stator in an embodiment of the present invention;

[0043] Figure 7 This is a schematic diagram of the welding fixture structure for the motor stator in an embodiment of the present invention;

[0044] Figure 8 This is an appendix to the embodiments of the present invention. Figure 7 Enlarged schematic diagram of the structure at point A;

[0045] Figure 9 This is a schematic diagram of a welding path in an embodiment of the present invention;

[0046] Figure 10 This is a schematic diagram of another welding path in an embodiment of the present invention.

[0047] Reference numerals: 1. Tooth; 10. Initial structural body; 11. First protrusion; 12. First groove; 13. Second groove; 20. Positioning fixture; 21. First limiting part; 211. First splicing part; 212. Third groove; 22. Second limiting part; 30. Limiting fixture; 301. Second splicing part; 31. First limiting part; 32. Second limiting part. Detailed Implementation

[0048] To further illustrate the technical means and effects adopted by this application to achieve its intended purpose, the specific implementation methods, structures, features, and effects according to this application are described in detail below with reference to the accompanying drawings and preferred embodiments. In the following description, different "an embodiment" or "an embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0049] Please refer to Figures 1 to 10 This application proposes a method for processing an electric motor stator, the processing method including:

[0050] S1. Based on the magnetostrictive characteristic parameters of the selected silicon steel sheet and the simulation results of the rated working magnetic flux density of the target motor, the expected circumferential magnetostrictive elongation of the toroidal core is calculated.

[0051] Specifically, S1 includes:

[0052] Based on the magnetostrictive characteristic parameters of the selected silicon steel sheet and the simulation results of the rated working magnetic flux density of the motor, the expected circumferential magnetostrictive elongation of the main body of the ring structure under the rated working magnetic flux density is determined. The magnetostrictive characteristic parameters refer to the physical property data of silicon steel material undergoing small deformation under the action of a magnetic field. Generally, it is the relationship curve between magnetostrictive strain and magnetic field strength or magnetic flux density, which can directly reflect the magnetomechanical coupling behavior of the material itself.

[0053] Based on the expected circumferential magnetostrictive elongation, the mating geometry parameters of the first protrusion 11 and the first groove 12 are designed, and a preload displacement matching the expected circumferential magnetostrictive elongation is formed at the mating position of the first protrusion 11 and the first groove 12.

[0054] This data can be obtained by consulting technical manuals or standard databases provided by material suppliers to obtain the magnetostrictive characteristic curves of specific grades of silicon steel sheets, or by experimental measurements, such as using strain gauges or laser displacement sensors to accurately measure the deformation of silicon steel sheet samples under different magnetic field intensities, thereby obtaining their magnetostrictive characteristic parameters. The "Simulation results of the rated operating magnetic flux density of the motor" refers to using computer-aided engineering (CAE) software to establish a three-dimensional model of the motor and apply electromagnetic field theory to simulate the electromagnetic characteristics of the motor under different operating conditions, such as magnetic field distribution, magnetic flux density, and magnetic field line orientation. Its purpose is to obtain the magnetic field strength and direction distribution of various regions inside the iron core of the motor under actual operating conditions, especially under rated operating magnetic flux density, providing spatial distribution information for the accurate calculation of magnetostrictive elongation. This simulation can be performed using finite element analysis (FEA) software to establish a geometric model of the motor core, set material properties, boundary conditions, and excitation sources, and conduct steady-state or transient electromagnetic field analysis; or by using numerical calculation methods such as the boundary element method (BEM) or finite difference method (FDM), combined with motor design parameters and operating conditions, to solve and visualize the electromagnetic field inside the motor.

[0055] Based on this, by coupling the magnetic field distribution data inside the iron core obtained from the simulation results of rated working magnetic flux density with the magnetostrictive characteristic parameters of the silicon steel sheet, the magnetostrictive strain of each part of the iron core along the circumference is integrated or weighted averaged to "determine the expected circumferential magnetostrictive elongation of the ring structure under rated working magnetic flux density". This step is one of the core objectives of the entire design process, aiming to quantify the overall circumferential dimensional change of the motor iron core due to the magnetostrictive effect under normal working load. For example, it can be further refined as follows: based on the material of the silicon steel sheet, the magnetostrictive strain curve of the silicon steel sheet as a function of magnetic flux density is obtained; based on the magnetostrictive strain curve, an electromagnetic field finite element analysis model of the target motor is established and simulated to obtain the magnetic field strength and direction distribution inside the silicon steel sheet of the tooth section of the motor stator under actual working conditions; the magnetic field strength and direction distribution inside the silicon steel sheet of the tooth section are combined with the magnetostrictive strain of the silicon steel sheet of the tooth section for synthesis calculation, and the volume of the iron core of the target motor is integrated to obtain the expected circumferential magnetostrictive elongation of the ring iron core.

[0056] Specifically, S1 includes:

[0057] S11. Based on the material of the silicon steel sheet, find the magnetostrictive strain curve of the silicon steel sheet as a function of magnetic flux density.

[0058] This curve describes the intrinsic physical properties of silicon steel sheets under different magnetic flux densities, resulting in deformation (elongation or contraction). It is the fundamental data for accurately calculating magnetostrictive elongation. This curve can be obtained by consulting the material data sheets, product specifications, or official websites of silicon steel sheet manufacturers. These documents typically provide magnetostrictive strain curves for specific grades of silicon steel sheets under standard test conditions. Alternatively, it can be obtained through experimental measurements. For example, using specialized magnetostrictive measurement equipment, strain measurements can be performed on silicon steel sheet samples under different magnetic field strengths, and the corresponding curves can be plotted. Commonly used measurement methods include laser interferometry and strain gauge methods.

[0059] S12. Based on the magnetostrictive strain curve, establish a finite element analysis model of the electromagnetic field of the target motor and perform simulation processing to obtain the magnetic field strength and direction distribution inside the silicon steel sheets of the motor stator under actual working conditions. Simulating the electromagnetic state of the motor under actual operation in a virtual environment to obtain accurate magnetic field distribution information inside the silicon steel sheets is a key step in combining the intrinsic properties of the material with the actual operating state of the motor. Professional rated operating magnetic flux density simulation software can be used. In these software programs, based on the motor's geometry, material properties (including the BH curve of the silicon steel sheets), and winding parameters, a 2D or 3D model is established, and rated operating conditions (such as rated current, frequency, speed, etc.) are set to perform transient or steady-state rated operating magnetic flux density simulation results. Alternatively, a simulation platform based on an open-source finite element library (such as FEMM or GetDP) or a self-developed algorithm can be used. By inputting motor design parameters and magnetic property data of silicon steel sheets, a mesh model can be constructed, and Maxwell's equations can be solved to obtain the magnetic flux density vector (including magnitude and direction) at each point inside the silicon steel sheet of the tooth. By simulating the working state of the silicon steel sheet of the tooth in the actual working environment, the magnetostriction change trend of the silicon steel sheet of the tooth under the working state can be accurately analyzed, so as to adjust the splicing state of the internal splicing structure according to the working state of the silicon steel sheet of the tooth to achieve a tight fit structural relationship.

[0060] S13. The magnetic field strength and direction distribution inside the toothed silicon steel sheet are combined with the hysteresis strain of the toothed silicon steel sheet for synthetic calculation, and the core volume of the target motor is integrated to obtain the expected circumferential magnetostrictive elongation of the toroidal core. By transforming the local, microscopic magnetic field distribution and material strain characteristics into the macroscopic, overall circumferential elongation of the toroidal core through synthesis and integration, this method bridges the gap between theoretical data and actual engineering parameters, ensuring the accuracy of the final preload displacement design.

[0061] Furthermore, in this embodiment, this can be achieved using post-processing software or custom scripts (such as Python or MATLAB). The magnetic flux density vector (magnitude and direction) and volume of each mesh element are extracted from the finite element simulation results. Then, based on the magnetostrictive strain curve of the silicon steel sheet, the magnetostrictive strain of each element in the direction of the local magnetic field is calculated and decomposed into the circumferential direction of the toroidal core. Finally, the circumferential strain components of all elements are volume-weightedly averaged and multiplied by the initial circumference of the core to obtain the total circumferential elongation.

[0062] Specifically, in this embodiment, non-oriented silicon steel sheet of type "35JNE250" is used as the core material for the motor for calculation and explanation. By consulting the material data sheet provided by the manufacturer of this silicon steel sheet, the curve data of magnetostrictive strain as a function of magnetic flux density in the rolling direction (RD) and transverse direction (TD) are obtained. For example, at a magnetic flux density of 1.5T, the magnetostrictive strain along the RD direction is approximately 8 × 10⁻⁻⁻⁶. 6 The value along the TD direction is approximately 5×10⁻ 6 Based on this, a 2D or 3D finite element model of the target motor can be established using software such as JMAG, which simulates the rated operating magnetic flux density. This model should accurately include the geometry of the stator core, the winding layout, and the BH magnetization curve of the selected silicon steel sheets. The simulation conditions are set to the motor's rated operating point, with a rated current of 10A and a rated speed of 3000rpm, to perform transient rated operating magnetic flux density simulation results. After the simulation, the magnetic flux density vector (including magnitude and direction) and volume of each finite element mesh element in the stator region can be exported from the results. Subsequently, data processing can be performed using MATLAB scripts. For each mesh element, based on the magnitude and direction of its magnetic flux density and the previously obtained magnetostrictive strain curve, the magnetostrictive strain of that element in the local magnetic field direction is calculated by interpolation. Then, these local strains are decomposed into the circumferential components of the toroidal core. Finally, the circumferential strain components of all toothed silicon steel sheet units are volume-weightedly averaged and multiplied by the initial mean diameter circumference of the toroidal core to accurately calculate the expected circumferential magnetostrictive elongation of the toroidal core. Through this calculation, the expected circumferential magnetostrictive elongation of the motor stator under rated operating magnetic flux density is determined to be 25 micrometers. Combining this with the number of splicing positions formed by several parts, the expected circumferential magnetostrictive elongation at each splicing position can be obtained, thus enabling precise adjustment of each splicing position.

[0063] S2. Based on the magnetostrictive elongation, design the mating geometry and size of the first protrusion 11 on one side of each tooth 1 of the motor winding and the first groove 12 on the other side. At the mating interface of the first protrusion 11 and the first groove 12 formed by any two adjacent teeth 1, a preload displacement is formed that is coordinated with the direction of the magnetostrictive elongation.

[0064] By using mechanical structure design to compensate for or counteract the deformation caused by magnetostriction, and by adjusting the fitting clearance to form a preload displacement, the motor stator can be matched with the magnetostrictive elongation of the silicon steel sheet during normal operation, thereby achieving an effective locking effect.

[0065] S3. Multiple teeth 1 are sequentially connected through the engagement of the first protrusion 11 and the first groove 12 to form an initial structure body 10. A winding machine is used to continuously wind the wire through the multiple teeth 1 of the initial structure body 10 to form a continuous coil on the initial structure body 10.

[0066] Specifically, the initial structural body 10 is placed in the working area of ​​the winding machine, with several teeth 1 arranged sequentially. The winding machine winds the teeth 1. The initial structural body 10 is divided into three-phase regions (u, v, w) based on the teeth 1. Winding begins with the first tooth 1 of each phase, and the winding operation of multiple teeth 1 within the same phase is completed sequentially. This ensures that the winding operation of each tooth 1 within each phase is completed based on a set of windings. There are no extra lead wires that need to be welded between the teeth 1 within the same phase, thereby ensuring the phase resistance balance and phase impedance matching of the initial structural body, avoiding local heat dissipation in the motor stator, and improving the working stability and reliability of the motor stator.

[0067] S4. The initial structural body 10 is fixed by positioning fixture and limiting fixture 30, and a pre-tightening displacement is applied to each mating position during the limiting process to form a ring-shaped structural body in a pre-tightened state.

[0068] Specifically, S4 includes:

[0069] A positioning fixture is formed based on a columnar first limiting part 21 and an annular second limiting part 22. The assembled annular structure body is fitted onto the first limiting part 21 of the positioning fixture. Specifically, the columnar first limiting part 21 is a component used to provide internal support and initial positioning. It can be a column with a stepped or conical surface to accommodate annular structure bodies with different inner diameters. The first limiting part 21 is usually made of high-strength, high-hardness materials, such as hardened steel or alloy steel, to ensure that it does not deform during the clamping process. The annular second limiting part 22 is a component used in conjunction with the first limiting part 21 to further fix the annular structure body. It can be a simple annular flange or a stepped ring with a specific inner and outer diameter, forming a tight fit with the first limiting part 21 to jointly constitute a stable internal support structure.

[0070] Specifically, the positioning fixture 20 is assembled based on the first limiting part 21 and the second limiting part 22, thereby reducing the manufacturing cost of the positioning fixture 20. That is, by processing the first limiting part 21 and the second limiting part 22 separately, and then splicing and fixing the first limiting part 21 and the second limiting part 22, the process flow and processing difficulty of the overall structure of the positioning fixture 20 can be simplified, thereby improving production efficiency and production convenience, and achieving the effect of reducing production costs.

[0071] The circumferential sidewall of the first limiting part 21 is provided with a plurality of third grooves 212. By providing the third grooves 212, it is convenient to insert the initial structural body 10 or to pull out the positioning fixture later. That is, by reserving the third grooves 212, the initial structural body 10 and the positioning fixture 20 can make contact based on the segmented curved surface, which can reduce the contact resistance when the initial structural body 10 is inserted into or pulled out of the positioning fixture 20, thereby improving the ease of assembly between the positioning fixture 20 and the initial structural body 10.

[0072] Furthermore, the second limiting part 22 is provided with a second protrusion, which is used to abut against the toothed silicon steel sheet at the first end of the initial structural body 10 to achieve positioning and limiting of the initial structural body 10. Based on the design of the second protrusion structure, a clearance part is formed between the bottom of the initial structural body 10 and the second limiting part 22. Based on the clearance part, the flow of glue during subsequent glue filling process can be facilitated, thereby improving the accuracy of the motor stator molding.

[0073] Specifically, a limiting fixture 30, forming a cylindrical structure based on several second splicing parts 301, is fitted onto the outside of the second end of the annular structural body, and the limiting member of the limiting fixture 30 presses against the annular structural body. The limiting fixture 30 being fitted onto the outside of the annular structural body means that the cylindrical limiting fixture 30 surrounds the annular structural body from the outside, providing external constraint. The limiting member of the limiting fixture 30 pressing against the annular structural body means that the limiting fixture 30 integrates a mechanism for applying pressure, such as a mechanical screw, hydraulic cylinder, or pneumatic device, which applies uniform radial pressure to the annular structural body through these limiting members, thereby achieving the application of preload displacement.

[0074] Furthermore, each second splice 301 is provided with multiple first limiting members 31 and second limiting members 32 at intervals. The first limiting members 31 and the second limiting members 32 are used to cooperate with the second grooves 13 of each tooth 1 on the initial structural body 10. Based on the cooperation of multiple first limiting members 31 and second limiting members 32 with the second grooves 13, it is used to ensure that the workpiece is in a predetermined position so that the weld is in a specified position when the winding is pressed into the welding fixture.

[0075] Furthermore, the first limiting member 31 is fully engaged with the second groove 13, and there is a gap between the second limiting member 32 and the second groove 13. In addition, there is a gap between the second splicing member 301 and the winding. In this embodiment of the invention, four first limiting members 31 are provided, and two second limiting members 32 are provided between any two adjacent first limiting members 31. In order to ensure sufficient gap, the second limiting member 32 and the second groove 13 retain a gap of 0.5mm, thereby preventing jamming when pressing in the welding workpiece.

[0076] Through the ingeniously designed positioning and limiting fixtures 30, precise control of the annular structure body during the limiting, fixing, and pre-tightening displacement application processes is achieved. First, the columnar first limiting part 21 and the annular second limiting part 22 of the positioning fixture work together to provide stable and precise internal support and positioning reference for the annular structure body. This internal interlocking method effectively eliminates radial and axial displacement errors during installation, ensuring the accuracy of its initial position. Based on this, the limiting fixture 30, a cylindrical structure formed by several second splicing parts 301, externally fits onto and surrounds the annular structure body. This combination of external constraint and internal positioning forms a double-protected fixing system. Subsequently, the limiting parts on the limiting fixture 30 uniformly press the annular structure body, precisely applying the pre-calculated pre-tightening displacement to each mating position. This strategy of combining internal and external components, positioning before pressing, ensures uniform pre-tightening force distribution throughout the circumference of the annular structure body, avoiding localized stress concentration or insufficient pre-tightening. In this way, the solution proposed in this application not only solves the problems of inaccurate positioning and uneven pre-tightening in traditional methods, but also provides a stable and reliable foundation for subsequent welding processes, making the weld formation more uniform and firm, thereby ensuring the overall performance and reliability of the motor stator.

[0077] S5. The main body of the ring structure is fitted into the welding fixture, and the welding is carried out in the yoke area along the length direction of tooth 1 using a local energy concentration welding method, so as to form a weld between adjacent teeth 1 of the initial main body 10.

[0078] S5 includes:

[0079] After the positioning fixture and the limiting fixture 30 are assembled, the ring structure body is fitted into the welding fixture.

[0080] The welding end of the driving welding equipment performs welding operations on the main body of the annular structure along a preset welding path.

[0081] Specifically, after the positioning fixture and limiting fixture 30 are assembled, the annular structure body is fitted into the welding fixture. The annular structure body refers to the integral structure formed through steps S1 to S4, consisting of multiple teeth 1 sequentially connected by the engagement of the first protrusion 11 and the first groove 12, and wound with a continuous coil. The positioning fixture and limiting fixture 30 are tools used to limit and fix the annular structure body and apply pre-tightening displacement in step S4. The welding fixture is a clamp or device specifically used to fix and support the annular structure body during welding. Its function is to ensure that the annular structure body maintains a precise position and orientation during welding, preventing displacement or deformation caused by welding thermal stress or operational vibration.

[0082] Furthermore, the welding end of the driving welding equipment performs welding operations on the annular structure body along a preset welding path. The welding equipment can be a laser welding device, which concentrates energy and applies it to the area to be welded via a laser head. The preset welding path refers to the movement trajectory of the welding end on the annular structure body determined before the welding operation through programming or teaching. This path ensures that welding energy can be precisely applied to the yoke region between adjacent teeth 1, forming the required weld.

[0083] Furthermore, the welding fixture is provided with several mating slots, which press the initial structural body 10 into the welding fixture, so that the splicing position of each tooth 1 of the initial structural body 10 is located at the position of several mating slots of the welding fixture. When the welding equipment performs welding operation along the preset welding line, the welding equipment can form a weld connection structure at the splicing position of each tooth 1.

[0084] Specifically, please refer to the welding circuit diagram corresponding to the welding fixture. Based on the arrangement of multiple welding circuits, the welding head of the welding equipment performs multiple welding operations on the initial structural body 10 along each welding circuit, thereby forming at least two weld seams between each adjacent tooth 1. Since each tooth 1 is a silicon steel sheet that is insulated from each other, eddy currents will be generated on each stack of silicon steel sheets. After laser welding, it is equivalent to destroying the insulation characteristics of the silicon steel sheets at the outer circle, causing the silicon steel sheets related to the weld to conduct, which will bring additional eddy current losses and increase the core temperature of the motor stator. By setting two weld seams to connect adjacent teeth 1, the overall structural stability of the motor stator is ensured and the heat generation is reduced.

[0085] Furthermore, based on the multi-segment welding operation, the weld seam is spirally varied, and under the overall structural design, at least two spiral lines are formed on the surface of the initial structural body 10, thereby improving the overall structural strength of the motor stator.

[0086] S6. After welding and fixing, the overall structure is potted with glue. High thermal conductivity insulating glue and high strength structural glue are used for potting. After curing, the motor stator is formed.

[0087] High thermal conductivity insulating adhesive and high strength structural adhesive are sequentially injected into the welded and fixed overall structure. The overall structure is encapsulated through a single injection process, and after curing, it forms the finished motor stator.

[0088] Specifically, S6 includes:

[0089] A second potting process can be used to encapsulate the welded and fixed overall structure. The first potting process involves using a high thermal conductivity insulating adhesive. This high thermal conductivity insulating adhesive typically refers to a polymer material with high thermal conductivity and good electrical insulation properties. Its main function is to efficiently conduct heat generated inside the motor stator to the outside while ensuring electrical insulation and preventing short circuits. This adhesive can use epoxy resin, silicone resin, or polyurethane as the base material and be filled with highly thermally conductive inorganic particles, such as alumina, boron nitride, zinc oxide, or silicon carbide, to significantly improve its thermal conductivity.

[0090] A second potting process using a high-strength structural adhesive is performed, followed by curing to form the finished motor stator. This high-strength structural adhesive is a polymer material with excellent mechanical strength, adhesion, and environmental resistance. Its main function is to provide robust structural support and protection for the motor stator, resisting mechanical stress, vibration, and impact. This adhesive can use modified epoxy resin, polyurethane, or acrylate as the base material, and its strength and toughness can be improved by adding toughening agents and reinforcing fibers.

[0091] Specifically, based on the first potting process, a first adhesive is first poured in to fully penetrate the windings and the gaps between teeth 1; then, based on the second potting process, a second adhesive is poured in to wrap the outer layer; wherein, the thermal conductivity of the first adhesive is greater than that of the second adhesive, and the mechanical strength of the second adhesive is greater than that of the first adhesive. The first potting process aims to ensure that the high thermal conductivity insulating adhesive fully penetrates into the tiny gaps between the coils of the motor stator and between teeth 1, forming a continuous heat conduction path and insulation layer. This process can be achieved through vacuum impregnation, pressure impregnation, or atmospheric pressure casting, among which vacuum impregnation can effectively remove air bubbles and ensure the penetration and fullness of the adhesive.

[0092] The second potting process utilizes a high-strength structural adhesive to form a robust protective layer on the exterior of the internal structure created after the first potting process, further enhancing the overall mechanical stability of the structure. This process can be achieved through methods such as mold pouring, coating, or encapsulation to ensure the uniformity and integrity of the outer protective layer. First, the first adhesive is poured in, allowing it to fully penetrate the windings and the gaps between the teeth. Then, the second adhesive is poured in to wrap around the outer layer. This layered potting strategy ensures that adhesives with different properties can perform their respective functions, optimizing overall performance. The first adhesive preferentially penetrates the interior, forming a highly efficient thermally conductive and insulating core; the second adhesive provides strong mechanical protection on the outer layer.

[0093] Furthermore, the thermal conductivity of the first adhesive compound is greater than that of the second adhesive compound, emphasizing its core role in thermal management and ensuring effective heat dissipation from the motor's interior. Meanwhile, the mechanical strength of the second adhesive compound is greater than that of the first, highlighting its crucial role in structural support and external protection, thus ensuring the stability and reliability of the motor stator during operation.

[0094] This embodiment provides a method for processing a motor stator, aiming to solve the problems of increased resistance, impedance imbalance, localized heating, and large space occupation caused by multiple welding points in the processing of motor stators in the prior art. By predicting magnetostrictive deformation and designing a corresponding pre-tightening structure, the problem of structural loosening caused by deformation during motor operation is effectively solved. Compared with the prior art method of individually winding each tooth 1 and performing multiple welding, this application achieves the initial structural body 10 through the mating connection of teeth 1, and then performs continuous winding on this basis, significantly reducing the number of welding points inside the winding. Thus, problems such as increased resistance, impedance imbalance, and localized heating caused by multiple welding are avoided. In addition, the continuous winding method also makes the winding structure more compact, reduces the space occupied by the lead wire, and thus improves the torque ratio of the motor. Applying pre-tightening displacement by positioning fixtures and limiting fixtures 30 ensures the tightness of the connection between teeth 1 and the rigidity of the overall structure. The welding method with localized energy concentration is performed under the pre-tightening state, which further improves the reliability of the connection and reduces thermal deformation. The stepped potting treatment comprehensively optimizes the heat dissipation and mechanical strength of the winding, improving the overall performance and service life of the product.

[0095] This invention also provides a motor stator, which includes: a ring-shaped main body formed by multiple teeth 1 arranged circumferentially, and a continuous coil wound on the teeth 1. Each tooth 1 is formed by stacking multiple layers of mutually insulated silicon steel sheets. Each tooth 1 has an arc-shaped first groove 12 on one side and a first protrusion 11 matching the first groove 12 on the other side. Adjacent teeth 1 are connected by the first protrusion 11 and the first groove 12. The mating structure of the first protrusion 11 and the first groove 12 forms a preload displacement. The direction of the preload displacement is the same as the direction of the circumferential deformation of the silicon steel sheet due to magnetostriction under the rated working magnetic flux density of the motor.

[0096] The annular structure of the motor stator is formed by multiple teeth 1 arranged circumferentially. This annular structure is the main part of the motor core, providing support and magnetic circuit channels for the coils. The annular structure can be formed by mechanically connecting multiple independent teeth 1 plates. Continuous coils wound on the teeth 1 are continuously wound on multiple teeth 1 to form one or more electrical circuits.

[0097] Furthermore, the coil can be continuously wound with enameled wire onto all teeth 1 in one go using automated winding equipment, forming a single integral winding. Each tooth 1 is composed of multiple layers of mutually insulated silicon steel sheets, which are typically thin sheets separated by insulating coatings or oxide layers. This laminated structure can be achieved by obtaining silicon steel sheets through methods such as stamping or laser cutting.

[0098] Specifically, each tooth 1 has an arc-shaped first groove 12 on one side and a first protrusion 11 matching the first groove 12 on the other side. The first groove 12 and the first protrusion 11 are geometric features designed on the side of the tooth 1 for interconnection. The first groove 12 can be semi-circular, elliptical, or other arc-shaped grooves, while the first protrusion 11 is correspondingly designed as a boss that matches the shape of the first groove 12. Adjacent teeth 1 are connected by the mating of the first protrusion 11 and the first groove 12. This mating connection can be a direct insertion fit or a fit with a certain gap, subsequently fixed by other methods. The mating structure of the first protrusion 11 and the first groove 12 forms a preload displacement, which refers to a preset, directional relative displacement or deformation between the protrusion and the groove during the mating connection. This preload displacement can be achieved through precise dimensional design to create an interference fit during mating; or by applying external force during assembly to cause elastic deformation of the mating surfaces. The direction of the preload displacement is the same as the direction of the circumferential deformation of the silicon steel sheet due to magnetostriction under the rated operating magnetic flux density of the motor. This means that if the silicon steel sheet will expand circumferentially under the rated operating magnetic flux density, the preload displacement should be the circumferential compression; if the silicon steel sheet will contract circumferentially, the preload displacement should be the circumferential stretching.

[0099] The motor stator of this application effectively solves the aforementioned technical problems through overall structural optimization. Specifically, the motor stator consists of a ring-shaped main body formed by multiple teeth 1 arranged circumferentially. This ring-shaped main body constructs a stable frame, providing reliable support for the coils and facilitating continuous winding, thereby avoiding the space occupation and complexity caused by traditional separate assembly. The continuous coil wound on the teeth 1 eliminates the multiple welding points required by traditional separate winding, significantly reducing the risk of resistance growth and impedance mismatch, and thus reducing the possibility of localized heating of the motor. Each tooth 1 is made of multiple layers of mutually insulated silicon steel sheets, effectively reducing eddy current losses and improving overall efficiency.

[0100] In terms of mechanical connection, adjacent teeth 1 are reliably fixed by the mating connection of the first protrusion 11 and the first groove 12. More importantly, the mating structure of the first protrusion 11 and the first groove 12 forms a preload displacement, which is applied during the processing stage, and its direction is the same as the direction of the circumferential deformation of the silicon steel sheet caused by magnetostriction under the rated operating magnetic flux density of the motor. This design allows the circumferential deformation of the silicon steel sheet caused by magnetostriction to be precisely offset by the preloaded preload during motor operation, thereby maintaining the stability and operational reliability of the motor stator structure. In this way, the motor stator of this application achieves high integration and stability in structure, reduces losses and heat generation in electrical performance, and effectively addresses the structural deformation problem caused by magnetostriction.

[0101] Specifically, any two adjacent teeth 1 of the motor stator are fixedly connected by a weld along the length of the splicing position; the splicing position of any two adjacent teeth 1 forms two or more welds. A fusion connection area is formed at the splicing position of adjacent teeth 1 of the motor stator using a laser welding device. The laser welding device includes a welding head and a rotating base. The initial structural body 10 is fixed on the rotating base, and the initial structural body 10 is driven to rotate by the rotating base. Laser welding is then performed on the initial structural body 10 based on the welding head.

[0102] Based on laser welding technology, a high-energy-density laser beam melts the material to form a narrow and deep weld, which has the advantages of a small heat-affected zone and small deformation. By forming two or more welds at any two teeth 1 splicing positions of the initial structural body 10, at least two spiral welding paths can be formed on the overall structural surface of the initial structural body 10, thereby improving the stability of the overall structure of the motor stator.

[0103] By fixing the stator between any two adjacent teeth 1 along the length of the splicing position using welds, the connection strength and rigidity between teeth 1 can be significantly improved, effectively preventing loosening or separation of teeth 1 due to magnetostrictive forces or mechanical vibrations during motor operation. Furthermore, by forming two or more welds at the splicing position of any two adjacent teeth 1, the reliability and redundancy of the connection are further enhanced. Even with minor defects in local welds, the overall structure remains stable, thereby extending the service life of the motor stator and ensuring the stability and reliability of motor operation. This welding fixing method, combined with a preset pre-tightening displacement, allows the motor stator to maintain structural integrity when subjected to magnetostrictive deformation, avoiding problems such as localized heating, increased noise, and performance degradation caused by structural loosening.

[0104] Specifically, the mating surfaces of the first protrusion 11 and the first groove 12 are provided with a wedge-shaped inclined surface mating structure, or the mating surfaces of the first protrusion 11 and the first groove 12 are provided with a micron-sized elastic bulge structure. The wedge-shaped inclined surface mating structure refers to a structure that achieves a tight connection and self-locking effect between mating parts through the interaction of surfaces with a specific inclination angle. For example, the wedge-shaped inclined surface mating structure can be manifested as one or both sides of the first protrusion 11 having a conical or trapezoidal cross-section, while the first groove 12 has a matching conical or trapezoidal slot, achieving a wedge-fit through radial or circumferential relative movement. Furthermore, the wedge-shaped inclined surface mating structure can also be implemented by providing a series of staggered inclined teeth 1 or inclined grooves on the mating surfaces. When the two mating surfaces move relative to each other, these inclined teeth 1 or grooves can mesh with each other, generating a tight locking force.

[0105] Specifically, the motor stator also includes a cured adhesive layer encapsulated on the annular structure body and the coil, wherein the cured adhesive layer partially penetrates into the mating interface between adjacent teeth 1 and the weld area. The cured adhesive layer encapsulated on the annular structure body and the coil refers to a material applied to the motor stator by filling and covering, which can provide insulation protection, moisture protection, dust protection, and shock resistance for the motor stator, enhance the overall structural strength, and improve heat dissipation performance.

[0106] The cured adhesive layer can be implemented using a double-layer encapsulation structure. For example, epoxy resin can be used as the first adhesive for inner encapsulation. Epoxy resin has excellent electrical insulation properties, mechanical strength, and chemical corrosion resistance, and forms a hard protective layer after curing. The first adhesive partially penetrates into the mating interface and weld area between adjacent teeth 1, meaning that during the potting process, the cured adhesive layer can penetrate into the tiny gaps and connection areas inside the motor stator. This penetration can effectively fill gaps, enhance local connection strength, improve heat conduction paths, prevent local stress concentration, and thus improve the overall reliability of the motor stator.

[0107] A second layer of encapsulation is formed on the surface of the first adhesive using a second adhesive compound with high structural strength, thereby stabilizing the overall structure of the motor stator. By introducing a specific curing adhesive layer design, the problem of insufficient adhesive penetration is effectively solved, thus improving the overall performance of the motor stator.

[0108] Specifically, the motor stator provided in this embodiment of the invention uses multiple silicon steel sheets stacked together to form teeth 1, which can simplify the winding process of the motor stator, improve the resistance consistency of each tooth 1 of the motor stator, and thus improve the manufacturing efficiency of the motor stator.

[0109] By combining the magnetostrictive properties of silicon steel sheets with adjustments to the splicing structure of adjacent teeth 1, and with the treatment of the weld structure, the overall rigidity of the motor stator structure is improved, thereby enhancing the stability and reliability of the overall motor stator structure.

[0110] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for processing a motor stator, characterized in that, The motor stator includes a ring structure body formed by multiple teeth arranged circumferentially and a continuous coil wound on the teeth. Each tooth is made of multiple layers of mutually insulated silicon steel sheets stacked together. Each tooth has an arc-shaped first groove on one side and a first protrusion that matches the first groove on the other side. Adjacent teeth are connected by the first protrusion and the first groove. The processing method includes: S1. Based on the material of the silicon steel sheet, find the magnetostrictive strain curve of the silicon steel sheet as a function of magnetic flux density; establish an electromagnetic field finite element analysis model of the target motor based on the magnetostrictive strain curve and perform simulation processing to obtain the magnetic field strength and direction distribution inside the silicon steel sheet of the tooth section under actual working conditions; combine the magnetic field strength and direction distribution inside the silicon steel sheet of the tooth section with the magnetostrictive strain of the silicon steel sheet of the tooth section for synthesis calculation, and perform integral calculation on the core volume of the target motor to obtain the expected circumferential magnetostrictive elongation of the annular core; S2. Based on the magnetostrictive elongation, design the mating geometry and size of the first protrusion on the side of each tooth of the motor winding and the first groove on the other side. At the mating interface of the first protrusion and the first groove formed by any two adjacent teeth, a pre-tightening displacement is formed that is coordinated with the direction of the magnetostrictive elongation. The direction of the pre-tightening displacement is the same as the circumferential deformation direction of the silicon steel sheet caused by magnetostriction under the rated working magnetic flux density of the motor. S3. Multiple teeth are sequentially connected through the engagement of the first protrusion and the first groove to form an initial structural body. A winding machine is used to continuously wind the wire through the multiple teeth of the initial structural body to form a continuous coil on the initial structural body. S4. The initial structural body is fixed by positioning and limiting fixtures. The positioning fixture includes a first limiting part with a columnar structure and a second limiting part with an annular structure. The initial structural body is fitted onto the first limiting part. The second limiting part is provided with a second protrusion. The second protrusion is used to abut against the toothed silicon steel sheet at the first end of the initial structural body and to form a clearance between the bottom of the initial structural body and the second limiting part. The limiting fixture is a cylindrical structure formed by several second splicing parts and is fitted onto the outside of the second end of the initial structural body. During the limiting process, the limiting part of the limiting fixture is used to uniformly press the initial structural body to apply a pre-tight displacement to each mating position, forming an annular structural body in a pre-tightened state. S5. The ring structure body is fitted into the welding fixture, and the welding is carried out in the yoke area along the tooth length direction using a local energy concentration welding method to form a weld between adjacent teeth of the initial structure body. S6. After welding and fixing, the overall structure is potted with glue, and after curing, it forms the finished motor stator.

2. The method for processing a motor stator according to claim 1, characterized in that, Each second splice is provided with multiple first and second limiting members at intervals. The first and second limiting members are used to cooperate with the second grooves of each tooth on the initial structural body.

3. The method for processing a motor stator according to claim 2, characterized in that, The first limiting member is fully engaged with the second groove, there is a gap between the second limiting member and the second groove, and there is a gap between the second splicing member and the winding.

4. The method for processing a motor stator according to claim 2, characterized in that, There are four first limiting members, and two second limiting members are provided between any two adjacent first limiting members. A 0.5mm gap is maintained between the second limiting members and the second groove.

5. The method for processing a motor stator according to claim 1, characterized in that, S5 includes: After the positioning and limiting fixtures are assembled, the main ring structure is fitted into the welding fixture. The welding end of the driving welding equipment performs welding operations on the main body of the annular structure along a preset welding path.

6. The method for processing a motor stator according to claim 1, characterized in that, S6 includes: The welded and fixed overall structure is treated with a first-stage potting process using high thermal conductivity insulating adhesive and high strength structural adhesive, which cures to form the finished motor stator.

7. The method for processing a motor stator according to claim 1, characterized in that, Any two adjacent teeth of the motor stator are fixedly connected by a weld along the length of the splicing position. The splicing position of any two adjacent teeth forms two or more welds.

8. The method for processing a motor stator according to claim 1, characterized in that, The mating surfaces of the first protrusion and the first groove are provided with a wedge-shaped inclined mating structure, or the mating surfaces of the first protrusion and the first groove are provided with a micron-sized elastic bulge structure.

9. The method for processing a motor stator according to claim 1, characterized in that, The motor stator also includes a curing adhesive layer that is potted on the annular structure body and the coil, and the curing adhesive layer partially penetrates into the mating interface between adjacent teeth and the weld area.

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