Stator, manufacturing method and electric machine

Abstract

The application discloses a stator, a manufacturing method and a motor, and belongs to the technical field of motors. The stator comprises a stator core, a continuous wave winding and a slot wedge assembly. The stator core comprises tooth portions and wire grooves which are arranged at intervals in the circumferential direction, and the wire grooves are open grooves. The continuous wave winding is radially embedded in the wire grooves. The slot wedge assembly is in the shape of a cylinder and comprises a plurality of body portions and a plurality of slot wedge portions which are alternately arranged in the circumferential direction. The slot wedge portions are recessed in the radial direction relative to the body portions. The slot wedge portions comprise two longitudinal beams which are arranged at intervals in the axial direction. The manufacturing material of the longitudinal beams comprises a magnetic conductive material. The longitudinal beams at least partially extend into the wire grooves and abut the circumferential walls of the tooth portions and the winding. The distance between the two longitudinal beams is smaller than the distance of the wire groove openings.

Description

Technical Field

[0001] This application belongs to the field of electric motor technology, and particularly relates to stators, manufacturing methods and electric motors. Background Technology

[0002] With the rapid development of new energy vehicle drive motors towards higher power density, higher efficiency, and higher reliability, flat wire motors, with their advantages of high slot fill factor, excellent heat dissipation, and high power density, have become the mainstream technology for automotive drive motors. Currently, flat wire motor stator windings mostly adopt hairpin or I-pin structures, formed by welding multiple conductor ends, resulting in a large number and dense distribution of winding joint solder points. During stator mass production, defects such as incomplete soldering, missing solder, and solder point oxidation are easily encountered due to factors such as welding processes, assembly precision, and operating environment. These defects not only cause a decrease in winding conductivity and an increase in contact resistance, leading to localized heating and increased losses, but also significantly reduce the long-term operational reliability of the windings, thus limiting the overall performance and service life of the motor.

[0003] To address the industry pain point of poor weld reliability in traditional segmented welded flat wire windings, continuous wave windings have become an important research and development direction for flat wire stators. This winding uses a single conductor for continuous winding, eliminating end weld joints and fundamentally eliminating the risk of incomplete welds, significantly improving the winding's conductivity stability and structural reliability. However, continuous wave windings need to be directly embedded radially into the stator winding slots, thus requiring an open slot structure to meet the winding assembly process requirements. However, the completely open slot openings cause a significant increase in the circumferential fluctuation of the air gap magnetic permeability between the stator and rotor, intensifying the tooth harmonic magnetic field and leading to increased stator iron and copper losses. Simultaneously, the cogging torque and torque pulsation increase significantly, resulting in higher vibration and noise levels during motor operation, deteriorating NVH performance and making it difficult to meet the high-quiet-sound requirements of new energy vehicles.

[0004] In existing technologies, after assembling a continuous wave winding in an open slot, a slot wedge is typically pressed into the slot opening to limit the axial and radial movement of the winding and prevent it from coming out of the slot under electromagnetic and centrifugal forces. Although this method approximates a closed structure by sealing the slot opening with the slot wedge, to ensure reliable fixation of the slot wedge, limiting grooves need to be machined in the stator teeth. This directly reduces the effective magnetic cross-sectional area of ​​the teeth, further aggravating air gap magnetic permeability distortion, leading to an abnormally large increase in slot leakage inductance and significantly degrading the electromagnetic performance of the motor. At the same time, slotting the teeth disrupts the overall continuity of the core teeth, resulting in a significant reduction in the mechanical strength of the teeth. Under long-term high-frequency alternating loads of the motor, stress concentration is likely to occur, causing problems such as tooth deformation or even cracking. This seriously weakens the overall structural reliability of the stator and greatly limits the engineering promotion and practical application of continuous wave wound open slot flat wire motors.

[0005] Therefore, it is necessary to design a stator core slot type and limiting structure that is compatible with continuous wave wound flat wire windings. Under the premise of meeting the requirements of direct radial embedding assembly of the windings, it can effectively reduce the inherent defects of large leakage flux and high leakage reactance of traditional open slots. At the same time, it can achieve reliable limiting and fixing of the windings without the need to open limiting grooves in the stator teeth, avoid damaging the magnetic cross-sectional area of ​​the teeth and the continuity of the overall structure, ensure the magnetic circuit performance and mechanical strength of the core, improve the electromagnetic performance and structural reliability of the motor, and promote the engineering application of continuous wave wound flat wire motors. Summary of the Invention

[0006] The present invention provides a stator, a manufacturing method, and an electric motor to at least solve or alleviate one or more technical problems in the prior art, or to at least provide a beneficial alternative.

[0007] To achieve the above objectives, the present invention provides the following technical solution: A stator, characterized in that it comprises a stator core, a continuous wave winding, and a slot wedge assembly; the stator core includes teeth and winding slots spaced apart along the circumferential direction, the winding slots being open slots; the continuous wave winding is embedded in the winding slots; The slot wedge assembly is cylindrical and includes multiple body portions and multiple slot wedge portions arranged alternately along the circumference. The slot wedge portions are recessed radially outward relative to the body portions. Each slot wedge portion includes two longitudinal beams arranged axially at intervals. The longitudinal beams are made of a magnetically conductive material. The longitudinal beams extend at least partially into the winding slot and abut against the peripheral wall of the winding and the teeth. The distance between the two longitudinal beams is less than the distance between the openings of the winding slots.

[0008] The stator winding slot has a fully open structure, which can directly realize the radial embedding of continuous wave winding without the need for threading or side winding processes, and the assembly process is simple. The winding is formed by a single conductor continuously without segmented end welding joints, which completely eliminates industry pain points such as poor soldering, missing soldering, solder joint oxidation, and high contact resistance from the root.

[0009] The integrated cylindrical slot wedge replaces the traditional single-slot independent slot wedge structure, allowing for coaxial assembly and press-fitting without the need for slot-by-slot installation. This simplifies the assembly process, improves mass production consistency, and significantly enhances production efficiency. By using a structure where the main body fits against the teeth and the slot wedge to press the winding, the winding is controlled in both radial and axial directions. This effectively resists the electromagnetic and centrifugal forces during high-speed motor operation, completely eliminating problems such as winding loosening, shifting, and disengagement. The winding fixation reliability is extremely high, effectively transforming the slot opening into a semi-closed shape. This achieves both assembly convenience and the excellent electromagnetic and noise reduction performance of semi-closed slots.

[0010] In a preferred embodiment, the longitudinal beam is connected to the body portion to form a snap-fit ​​structure that engages with the radially inner end of the tooth portion.

[0011] In a preferred embodiment, the circumferential side of the longitudinal beam is formed with a burr protruding radially inward, and the radial inner surface of the longitudinal beam and the body portion form a relief groove to accommodate the burr, wherein the protrusion size of the burr is not greater than the depth of the relief groove.

[0012] In a preferred embodiment, the slot wedge portion further includes at least two crossbeams connected to the longitudinal beam and abutting against the winding, with the multiple crossbeams arranged at axial intervals and a magnetic isolation hole formed between adjacent crossbeams.

[0013] By combining the solid sealing of the slot wedge with the hollowing out of the small-sized magnetic isolation hole, the original open slot is equivalently transformed into a standard semi-closed slot. This avoids the defects of large magnetic permeability fluctuation, severe harmonics and poor NVH of open slots, and avoids the problems of magnetic circuit blockage and excessive magnetic resistance of fully closed slots. The limited size of the magnetic isolation hole can effectively extend the circumferential magnetic guide length of the stator teeth, smooth the abrupt change in air gap magnetic permeability, significantly suppress tooth harmonic magnetic field, reduce motor iron loss and copper loss, reduce cogging torque and torque pulsation, and greatly optimize motor quietness and operating efficiency.

[0014] In a preferred embodiment, the main body, the crossbeam, and the longitudinal beam are integrally formed.

[0015] The overall substrate has uniform mechanical properties, no stress concentration points, high structural strength, and is not easily deformed or cracked under long-term alternating loads, resulting in a longer service life.

[0016] In a preferred embodiment, the crossbeam and the longitudinal beam are detachably connected; The crossbeam is made of a non-magnetic material, and / or the body is made of a non-magnetic material.

[0017] In a preferred embodiment, a crossbeam is provided at both ends of the groove wedge, and the axial length of the magnetic isolation hole is less than the axial length of the longitudinal beam and not less than half of the axial length of the longitudinal beam.

[0018] In a preferred embodiment, the two circumferential edges of the slot wedge assembly are connected by overlapping or snap-fitting, and the side splicing gap of the slot wedge assembly is located at the body portion.

[0019] An electric motor includes a rotor and the stator described above.

[0020] A method for manufacturing a stator includes: The rectangular silicon steel sheet is subjected to a first stamping process to form multiple alternating body parts and multiple protrusions, such that the protrusions protrude relative to the first side of the body part. The protrusion is subjected to a second stamping process to form a slotted wedge including a longitudinal beam, a transverse beam, and a magnetic isolation hole; the stamping direction of the second stamping process is from the first side of the body portion to the second side of the body portion. Rectangular silicon steel, after undergoing two stamping processes, is wound into a cylindrical shape to obtain a slotted wedge assembly; The stator is obtained by sequentially assembling insulating paper, continuous wave winding, and slot wedge assembly onto the stator core.

[0021] The above structure has the following beneficial effects: The stator of this application, relying on the stator open slot structure, can directly radially embed continuous wave windings, and the assembly process is simple and efficient. Through the integrated slot wedge assembly and the magnetic isolation hole structure, the open slot is equivalently transformed into a semi-closed slot, which effectively smooths the circumferential fluctuation of the air gap magnetic permeability, suppresses the tooth harmonic magnetic field, reduces the iron loss, copper loss and slot leakage inductance of the motor, reduces the cogging torque and torque pulsation, significantly optimizes the motor's NVH quiet performance and operating efficiency, and solves the pain points of poor electromagnetic performance and high noise of traditional open slot motors.

[0022] By abandoning the tooth slotting process required for traditional slot wedge limiting, the complete magnetic cross-sectional area of ​​the stator teeth and the continuity of the iron core structure are fully preserved. This avoids electromagnetic problems such as magnetic circuit distortion and increased magnetic leakage caused by tooth slotting, and also eliminates mechanical hazards such as stress concentration, deformation and cracking of the teeth, thus ensuring the excellent magnetic circuit performance of the motor and the overall structural strength of the stator.

[0023] The cylindrical integral slot wedge assembly, combined with the full-range interference fit design, can achieve reliable radial and axial bidirectional limiting of the winding, with a tight fit without gaps or loosening or offset. It can effectively resist the electromagnetic force, centrifugal force and alternating load during high-speed operation of the motor, and completely eliminate the problems of winding slippage, disengagement and abnormal noise. It is suitable for the complex working conditions of high frequency, high temperature and high speed in new energy vehicles.

[0024] The slot wedge assembly, while fixing the winding, allows the combination of the slot wedge and the open slot to be equivalent to a semi-closed slot. This improves the permeability variation amplitude of the air gap magnetic circuit, reduces tooth harmonics, helps reduce stator losses, improves NVH (noise, vibration, and harshness), and also aids in winding heat dissipation. The crossbeam helps ensure the structural strength of the slot wedge, thereby ensuring the structural strength of the slot wedge assembly and improving its stability and reliability.

[0025] The slot wedge is formed by integral stamping and rolling of a sheet, combined with a closed-loop connection structure of overlapping and dovetail slot snap-fit. It has high overall precision, good roundness, and strong structural rigidity. It does not require complicated assembly procedures and can be press-fitted as a whole, with high assembly consistency and fast production efficiency. The two magnetic isolation hole structures can be adapted to different power and speed models, with wide adaptability, effectively reducing production costs and helping the engineering popularization and application of continuous wave wound flat wire motors. Attached Figure Description

[0026] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and, together with their description, serve to explain this application and do not constitute an undue limitation of the invention. In the drawings: Figure 1 A schematic diagram of the stator structure provided in this embodiment is shown; Figure 2 A top view of the stator structure after the windings are removed in this embodiment is shown. Figure 3 A three-dimensional view of the structure of the stator after the windings are removed in this embodiment is illustrated. Figure 4 It is illustrated Figure 3 A schematic diagram of the exploded structure; Figure 5 A schematic diagram of the stator core structure is shown. Figure 6 A schematic diagram of the unfolded slot wedge assembly is shown; Figure 7 A schematic diagram of the overlapping structure on both sides of the slot wedge assembly is shown; Figure 8 A schematic diagram of another type of slotted wedge assembly with overlapping structures on both sides is shown; Figure 9 A partially enlarged view of the slot wedge assembly mating with the stator core is shown; Figure 10 A partially enlarged schematic diagram of the slotted wedge assembly from the first perspective is shown; Figure 11 A partially enlarged schematic diagram of the slot wedge assembly from a second perspective is shown; Figure 12 A partially enlarged schematic diagram of the slot wedge assembly from a third perspective is shown; Figure 13 A schematic diagram of one implementation of the magnetic shielding hole layout is shown; Figure 14 A schematic diagram of one embodiment in which the burr is located in the clearance groove is shown; Label Explanation: 1. Stator core; 10. Tooth section; 11. Winding slot; 2. Continuous wave winding; 3. Slot wedge assembly; 30. Body section; 300. Lap joint; 301. Snap-fit ​​dovetail slot; 31. Slot wedge section; 310. Magnetic isolation hole; 3100. Longitudinal beam; 3101. Crossbeam; 3102. Burr; 3103. Clearance slot. Detailed Implementation

[0027] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit and scope of the invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0028] First, the technical concept of the technical solution disclosed in this invention will be explained.

[0029] Stator core slots are mainly classified into open slots, semi-open slots, and closed slots.

[0030] Closed slots have essentially sealed slot openings and intact slot walls, resulting in good magnetic circuit closure in the stator core teeth. Their biggest advantages are minimal slot leakage flux and end leakage flux, fewer harmonic magnetic fields, lower stray motor losses, lower operating noise, and better suppression of high-frequency electromagnetic interference. However, their disadvantages are also significant: the closed slot openings make wire embedding and unwinding processes more difficult, insulation treatment is inconvenient, and the high slot magnetic reluctance increases the excitation current. Additionally, the slot leakage resistance is relatively high, leading to poor compatibility with high-power, large-diameter windings.

[0031] The semi-open slot, with its moderately wide opening, offers the best overall performance. Neither completely closed nor excessively open, its leakage flux and resistance are at moderate levels. This avoids the problems of excessive leakage resistance and winding difficulties associated with closed slots, while also preventing excessive leakage flux like open slots. Electromagnetically, it effectively reduces harmonic losses, and mechanically, it facilitates winding installation and insulation arrangement. Balancing electromagnetic performance, manufacturing processes, and heat dissipation, it is suitable for medium to large-sized AC motors and high-voltage motors, making it the slot structure with the highest overall cost-effectiveness in engineering applications.

[0032] Open slots have completely open openings, with the slot width roughly the same as the slot body. This simplifies the winding and unwinding processes and facilitates convenient winding insulation installation, making them suitable for shaped windings and large-section conductor processing. However, the open slot openings cause a sharp increase in slot leakage flux, resulting in higher leakage reactance, decreased motor power factor and efficiency, severe tooth flux distortion, high harmonic content, and significantly increased noise, vibration, and stray losses during operation. Therefore, they are mostly used for small, low-voltage motors and equipment with relatively low electromagnetic performance requirements, exhibiting significant overall performance limitations.

[0033] Continuous wave windings, as an important research and development direction for flat wire stators, are formed by continuously winding a single conductor without end welding joints. This eliminates the risk of incomplete welding at the source and significantly improves the conductivity stability and structural reliability of the winding. However, continuous wave windings need to be directly embedded into the stator slots radially. Due to assembly process constraints, traditional solutions must use open slot structures. However, with completely open slot openings, the slot leakage flux is large, the leakage reactance is relatively high, which easily aggravates harmonic losses and reduces the power factor of the motor. The overall electromagnetic performance is not as good as that of semi-open slots.

[0034] In existing technologies, after assembling a continuous wave winding in an open slot, a slot wedge is typically pressed into the slot opening to limit the axial and radial movement of the winding and prevent it from dislodging from the slot under electromagnetic and centrifugal forces. While this method approximates a closed slot opening through wedge sealing, ensuring reliable wedge fixation requires machining limiting grooves in the stator teeth. This directly weakens the effective magnetic cross-sectional area of ​​the teeth, exacerbates air gap magnetic distortion, further increases slot leakage inductance, and significantly degrades the motor's electromagnetic performance. Simultaneously, creating limiting grooves in the teeth disrupts the overall continuity of the stator core teeth, leading to a significant reduction in their mechanical strength. Under long-term high-frequency alternating loads, this can easily cause stress concentration, tooth deformation, and even cracking, severely reducing the overall structural reliability of the stator and hindering the practical engineering application of continuous wave wound open slot flat wire motors.

[0035] In view of the aforementioned problems, the present invention provides a stator, a manufacturing method, and a motor. The invention will now be described with reference to the accompanying drawings.

[0036] The specific solution adopted is as follows: like Figure 1-14 As shown, the present invention provides a stator, including a stator core 1, a continuous wave winding 2, and a slot wedge assembly 3; the stator core includes teeth 10 and winding slots 11 arranged circumferentially, the winding slots being open slots; the continuous wave winding is embedded in the winding slots; the slot wedge assembly is cylindrical, including multiple body parts and multiple slot wedge parts arranged alternately circumferentially, the slot wedge parts being recessed radially outward relative to the body parts, the slot wedge parts including two longitudinal beams arranged axially at intervals, the longitudinal beams being made of a magnetically conductive material, the longitudinal beams at least partially extending into the winding slots and abutting against the peripheral walls of the winding and the teeth, the distance between the two longitudinal beams being less than the distance between the openings of the winding slots.

[0037] The stator of this application features an open-slot structure in its core, meeting the requirements for direct radial mounting of continuous wave windings. This eliminates end-welded joints, removing the risk of weld point failure. Slot wedge assemblies are installed, simultaneously abutting against the inner circumferential wall of the teeth and the winding, achieving radial and axial positioning and preventing dislodgement. The area where the slot wedges contact the teeth forms a magnetic bridging zone, reducing the actual slot opening and effectively transforming the open slot into a semi-closed slot. By eliminating the need for machining limiting grooves in the stator teeth, the complete magnetic cross-section and integrated structure of the teeth are preserved, improving the winding's conductivity stability and operational reliability. The open-slot structure allows for smooth continuous wave winding mounting, maintaining the high reliability characteristic of weld-free mounting. The assembled slot wedge assemblies position and fix the winding, simultaneously forming a magnetic bridging zone, effectively transforming the slot opening into a semi-closed shape, thus achieving both assembly convenience and the excellent electromagnetic and noise reduction performance of semi-closed slots.

[0038] See Figure 4 and Figure 9 and Figure 11The slot wedge assembly is a monolithic cylindrical structure, circumferentially divided into a body portion 30 and a slot wedge portion 31. The body portion is radially concave inward, its outline fitting snugly against the inner wall of the stator teeth. The slot wedge portion is radially convex outward, its size and shape adapted to the specifications of the winding slot opening. The slot wedge portion includes two longitudinal beams arranged axially at intervals. The longitudinal beams are made of a magnetically conductive material, and the longitudinal beams extend at least partially into the winding slot and abut against the circumferential wall of the winding and the teeth. The distance between the two longitudinal beams is less than the distance between the openings of the winding slots. The two longitudinal beams are made of a magnetically conductive material, and together they form a magnetically conductive bridge in the area fitting the teeth.

[0039] In addition, magnetically conductive materials include silicon steel, SMC (soft magnetic composite material), etc.

[0040] The longitudinal beam is connected to the main body to form a snap-fit ​​structure that engages with the radial inner end of the tooth. During assembly, the cylindrical slot wedge assembly is coaxially fitted into the inner side of the stator core. The inwardly recessed main body is positioned and limited against the inner circumferential wall of the stator tooth. The outwardly protruding slot wedge is snapped into the slot opening of each winding slot, and the end presses against the continuous wave winding in the slot to complete the winding fixation.

[0041] The integrated cylindrical structure allows for seamless assembly, eliminating the need for individual slot wedge installations, reducing assembly steps and improving mass production efficiency. The concave and convex shapes are designed to fit the teeth and slots respectively, ensuring a high degree of fit and bidirectional winding locking. This effectively resists electromagnetic and centrifugal forces, preventing winding loosening and disengagement. The slot wedges seal and reduce slot opening, effectively creating semi-closed slots, suppressing tooth harmonics and leakage flux, reducing losses, minimizing torque pulsation, and improving motor vibration and noise.

[0042] Furthermore, during the assembly of the cylindrical slot wedge assembly, the body portion 30 and the inner wall of the stator tooth portion 10, and the slot wedge portion 31 and the slot opening of the winding slot 11 are all assembled using an interference fit. The slot wedge assembly is coaxially pressed into the inner side of the stator core, and the interference fit generates a clamping force, making the body portion tightly fit the tooth portion, and the slot wedge portion securely clamps the slot opening and compacts the winding. After assembly, there is no gap or misalignment among the mating surfaces, and the overall position remains fixed.

[0043] As a preferred embodiment of this application, see [link to application]. Figure 10 and Figure 11A magnetic isolation hole 310 is provided on the slot wedge, and the circumferential length of the magnetic isolation hole 310 is smaller than the width of the winding slot itself. After the cylindrical slot wedge assembly is press-fitted into place with an interference fit, the slot wedge seals most of the slot opening area, leaving only the magnetic isolation hole to form a local magnetic passage gap, thus forming an equivalent semi-closed slot structure. The size of the magnetic isolation hole is limited and will not exceed the width of the wire slot. Relying on the solid part of the slot wedge, the effective circumferential magnetic conduction length of the tooth is effectively extended, and a semi-closed slot shape is precisely formed. This is different from a completely sealed closed slot, which optimizes the magnetic circuit distribution and reasonably preserves the magnetic flux passage space. The circumferential dimension of the magnetic isolation hole is smaller than the slot width, which effectively expands the circumferential magnetic conduction range of the tooth. The slot wedge still stably limits the winding, taking into account both structural stability and electromagnetic compatibility, and the overall performance is balanced.

[0044] As a preferred embodiment of this invention, the slot wedge portion further includes at least two crossbeams connected to the longitudinal beam and abutting against the winding, with the multiple crossbeams arranged at axial intervals and magnetic isolation holes formed between adjacent crossbeams.

[0045] In this design, the slot wedge portion 31 has multiple independent magnetic isolation holes 310 spaced apart along the axial direction. The slot wedge portion is also equipped with two full-length longitudinal beams, the axial length of which is consistent with that of the tooth portion. Multiple crossbeams are integrally formed between two adjacent magnetic isolation holes to form a segmented support frame. The two longitudinal beams are made of magnetically conductive material, forming a continuous magnetically conductive bridging area based on the solid area of ​​the longitudinal beams.

[0046] As another preferred embodiment of this example, each of the two axial ends of the slot wedge is provided with a crossbeam, and the axial length of the magnetic isolation hole is less than the axial length of the longitudinal beam and not less than half of the axial length of the longitudinal beam.

[0047] In this design, an axially extending elongated magnetic isolation hole is opened in the slot wedge portion. The slot wedge frame consists of two crossbeams and two longitudinal beams 3100. The two crossbeams 3101 are respectively located at both ends of the elongated magnetic isolation hole in the axial direction. The two longitudinal beams are made of magnetically conductive material and together with the tooth area form a magnetically conductive bridging area, which minimizes magnetic leakage and improves heat dissipation performance.

[0048] In both structures, the magnetic longitudinal beam fills the gap in the slot, effectively extending the circumferential magnetic length of the tooth, and the magnetic isolation hole leaves a reasonable magnetic space, which not only meets the winding assembly limit requirements, but also realizes the semi-closed slot electromagnetic configuration. The role of the crossbeam is only to ensure the structural strength of the slot wedge.

[0049] In a preferred embodiment of this application, the crossbeam and the longitudinal beam are detachably connected; for example, a connector is provided at the end of the crossbeam, and a corresponding slot is provided on the longitudinal beam; the connector is embedded in the slot to achieve the insertion and engagement of the crossbeam and the longitudinal beam, or other methods may be used. The manufacturing material of the crossbeam includes non-magnetic materials, and / or the manufacturing material of the body part includes non-magnetic materials.

[0050] In slot wedge assemblies, the crossbeam and body are non-magnetic. For example, the main body of the slot wedge assembly is first formed by pressing non-ferrous metals such as copper and aluminum, or organic polymer materials such as PEEK and PPS, and then the non-magnetic crossbeam is installed. The body and crossbeam can be made of non-magnetic materials.

[0051] See Figure 13 The magnetic isolation holes in the slot wedge extend axially, which can reduce the amount of crossbeams and further reduce magnetic leakage.

[0052] As a preferred embodiment of this application, see [link to application]. Figure 6 The slot wedge assembly of this application uses a sheet metal substrate, which is integrally cut and formed by stamping process, directly bringing out the spaced-out body part and slot wedge part structure; after stamping, the whole substrate is rolled and bent along the circumferential direction, and finally enclosed to form an integral cylindrical slot wedge assembly. The integral stamping process results in strong component integrity, eliminates multiple parts assembly steps, reduces assembly errors, and makes the winding limit and magnetic conduction effect more stable.

[0053] Further, see Figure 7 and Figure 8 After being stamped, the sheet substrate is rolled and enclosed into a cylindrical shape. The two circumferential edges of the component are closed and connected by overlapping and snap-fitting. The side splicing gaps are uniformly arranged in the body part, avoiding the functional area of ​​the slot wedge part.

[0054] The two sides of the stepped overlapping section are respectively processed to fit the stepped structure, i.e., the overlapping part is 300. After rolling, the two steps fit together and are aligned. After splicing, the inner and outer wall surfaces of the cylinder are flat without protrusions or misalignments. The bonding surface can be fixed with adhesive to ensure the regularity of the circumferential outline.

[0055] The dovetail groove 301 has a dovetail cavity on one side edge and a dovetail tenon integrally formed on the other side edge. After being rolled, the tenon is embedded into the groove to achieve a snap-lock. After being snapped in place, it can be combined with adhesive or spot welding processes to strengthen the connection strength.

[0056] The splicing gap is located in the main body, which will not interfere with the limiting function of the slot wedge winding, and the electromagnetic performance and fixing effect are not affected.

[0057] It can flexibly choose bonding or welding reinforcement methods to adapt to different working conditions and strength requirements, and the overall structure is stable and not easy to loosen or deform.

[0058] A method for manufacturing the stator, comprising: S1, the rectangular silicon steel sheet is subjected to the first stamping process to form multiple body parts and multiple protrusions arranged alternately, so that the protrusions protrude relative to the first side of the body part. S2, the protrusion is subjected to a second stamping process to form a slot wedge including longitudinal beams, transverse beams and magnetic isolation holes; the stamping direction of the second stamping process is from the first side of the body to the second side of the body. S3, the rectangular silicon steel that has undergone two stamping processes is wound into a cylindrical shape to obtain the slot wedge assembly; S4. The insulating paper, continuous wave winding and slot wedge assembly are sequentially assembled into the stator core to obtain the stator.

[0059] See Figure 14 In S2, the stamping direction of the second stamping process is from the side of the protrusion away from the body to the side closer to the body. By controlling the stamping pressure of the second stamping process, the depth of the clearance groove formed by the radial inner surface of the longitudinal beam and the body can be controlled. This prevents burrs on the crossbeams and longitudinal beams from protruding and keeps them hidden in the clearance groove. During and after assembly into the stator core, this avoids burrs contacting the insulation paper and causing damage. Therefore, no post-processing of burrs is required, reducing processing steps.

[0060] As a preferred embodiment of this application, an electric motor includes a stator.

[0061] This motor includes core components such as a housing, a rotor assembly, a stator with the aforementioned novel slotted wedge assembly, end covers, and a rotating shaft. The stator is fixedly assembled inside the housing, and the rotor assembly is coaxially rotatable in the inner cavity of the stator.

[0062] The stator consists of a stator core, a continuous wave winding, and a cylindrical slot wedge assembly. The teeth and open winding slots are evenly distributed on the inner side of the stator core. The continuous wave winding is radially embedded into the winding slot. The winding has no segmented welding joints, thus eliminating weld point failure defects from the source.

[0063] The slot wedge assembly is formed by stamping a sheet substrate into a single unit, consisting of a main body and a slot wedge. The components are then wound into a cylindrical structure. The circumferential sides are closed using stepped overlaps or dovetail groove snap-fits, with the joint located at the main body. The assembly is fitted into the inner side of the stator core with an interference fit. The main body conforms to the inner wall of the tooth section, while the slot wedge extends into the slot opening to press against the winding, achieving positioning and preventing disengagement.

[0064] The slot wedge has magnetic isolation holes with a circumferential dimension smaller than the width of the slot. There are two types: single axial long hole and multiple axial arrangement holes. Two magnetic guiding longitudinal beams are set on both sides of the slot wedge to form a magnetic guiding bridging area. With the help of solid sealing and hollow hole positions, the original open slot is equivalently transformed into a semi-closed slot structure.

[0065] Overall machine operation advantages With no welded joints in the windings, the electrical conductivity is stable, and abnormal heat loss is less likely to occur during long-term operation, thus greatly improving the reliability of motor operation.

[0066] The equivalent semi-closed slot effectively smooths out air gap magnetic permeability fluctuations, suppresses tooth harmonics, reduces iron and copper losses, and improves operating efficiency.

[0067] By reducing cogging torque and torque pulsation, motor vibration and noise are significantly reduced, and NVH performance meets the quiet requirements of new energy vehicles.

[0068] The stator teeth do not require machining of limiting grooves, the magnetic circuit is intact, the mechanical strength is good, it can withstand high-frequency alternating loads, and the service life of the whole machine is longer.

[0069] The slot wedge is integrally stamped and wound, which makes assembly convenient and consistent, suitable for mass production of motors, and has excellent overall performance.

[0070] For any parts not mentioned in this invention, existing technologies can be used or referenced.

[0071] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various variations or substitutions within the technical scope disclosed in the present invention, and these should all be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A stator, characterized in that, It includes a stator core, a continuous wave winding, and a slot wedge assembly; the stator core includes teeth and winding slots spaced apart along the circumference, and the winding slots are open slots; the continuous wave winding is embedded in the winding slots; The slot wedge assembly is cylindrical and includes multiple body portions and multiple slot wedge portions arranged alternately along the circumference. The slot wedge portions are recessed radially outward relative to the body portions. Each slot wedge portion includes two longitudinal beams arranged axially at intervals. The longitudinal beams are made of a magnetically conductive material. The longitudinal beams extend at least partially into the winding slot and abut against the peripheral wall of the winding and the teeth. The distance between the two longitudinal beams is less than the distance between the openings of the winding slots.

2. The stator according to claim 1, characterized in that, The longitudinal beam is connected to the main body to form a snap-fit ​​structure that engages with the radial inner end of the toothed part.

3. The stator according to claim 1, characterized in that, The longitudinal beam has burrs protruding radially inward on its circumferential side. The radial inner surface of the longitudinal beam and the body portion form a relief groove to accommodate the burrs. The protruding size of the burrs is not greater than the depth of the relief groove.

4. The stator according to claim 1, characterized in that, The slot wedge also includes at least two crossbeams connected to the longitudinal beam and abutting against the winding. The multiple crossbeams are arranged at intervals along the axial direction, and a magnetic isolation hole is formed between two adjacent crossbeams.

5. The stator according to claim 4, characterized in that, The main body, the crossbeam, and the longitudinal beam are integrally formed.

6. The stator according to claim 4, characterized in that, The crossbeam and the longitudinal beam are detachably connected; The crossbeam is made of a non-magnetic material, and / or the body is made of a non-magnetic material.

7. The stator according to claim 4, characterized in that, Each of the two axial ends of the groove wedge is provided with a crossbeam, and the axial length of the magnetic isolation hole is less than the axial length of the longitudinal beam and not less than half of the axial length of the longitudinal beam.

8. The stator according to claim 1, characterized in that, The two circumferential edges of the slotted wedge assembly are connected by overlapping or snap-fitting, and the side splicing gap of the slotted wedge assembly is located at the body part.

9. An electric motor, characterized in that, include: The rotor and the stator according to any one of claims 1 to 8.

10. A method for manufacturing a stator as described in any one of claims 3-5, characterized in that, include: The rectangular silicon steel sheet is subjected to a first stamping process to form multiple alternating body parts and multiple protrusions, such that the protrusions protrude relative to the first side of the body part. The protrusion is subjected to a second stamping process to form a slotted wedge including a longitudinal beam, a transverse beam, and a magnetic isolation hole; the stamping direction of the second stamping process is from the first side of the body portion to the second side of the body portion. Rectangular silicon steel, after undergoing two stamping processes, is wound into a cylindrical shape to obtain a slotted wedge assembly; The stator is obtained by sequentially assembling insulating paper, continuous wave winding, and slot wedge assembly onto the stator core.

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