A method and device for pre-anchoring and self-bonding of stator silicon steel sheets by pulsed laser

Abstract

The application discloses a kind of stator silicon steel sheet pulse laser pre-anchoring and induction self-bonding method and device, belong to motor stator core technical field, method includes: in the outer edge of stator silicon steel sheet setting local anchoring area, then stator silicon steel sheet is positioned and stacked, after the height of stack reaches preset, axial pre-pressure is applied;Identify the interface of laminated sheet, and apply pulse laser, form local fusion zone, multiple local fusion zones constitute micro-point anchoring connection spaced along the direction of stack height and / or circumferentially, and do not form continuous metal connection path through all laminated sheet interfaces;Induction heating under axial pressure, make self-bonding layer heat activated to form interlayer surface connection, then pressure is maintained, temperature is uniform, cooling is shaped, quality is detected.Micro-point anchoring connection limits the radial and circumferential slip of laminated sheet before self-bonding layer solidification, and self-bonding layer forms interlayer connection and vibration damping.The application helps to consider laminated sheet positioning stability, bonding solidification consistency, anti-vibration reliability and magnetic property retention.

Description

Technical Field

[0001] This invention relates to the field of stator core manufacturing technology for small motors, and in particular to a method and apparatus for pulsed laser pre-anchoring and induction self-adhesion of stator silicon steel sheets. Background Technology

[0002] Unmanned equipment such as drones, unmanned vehicles, unmanned ships, and inspection robots typically require drive motors to be small in size, lightweight, high in power density, and adaptable to vibration, shock, and frequent start-stop conditions. The stator core is usually formed by stacking multiple thin silicon steel sheets with insulating layers on their surfaces. The stacking position of the silicon steel sheets, the interlayer insulation state, the connection strength, and the dimensional consistency affect the mechanical and electromagnetic properties of the stator core.

[0003] Existing stator silicon steel sheet connection methods mainly include fastening, riveting, welding, and bonding. Fastening and riveting can cause localized plastic deformation and stress concentration in the silicon steel sheets. Although continuous welding can achieve high connection strength, it is prone to forming a large area of ​​metal conduction between the laminations, and generating welding heat-affected zones and residual stress.

[0004] Self-adhesive silicon steel sheets form a large-area interlayer bond by setting a thermally activated adhesive layer on the surface of the silicon steel sheet, under the action of pressure and temperature, which can reduce the need for fastening, riveting, and continuous welding structures. Existing induction heating schemes for self-adhesive coated silicon steel cores can achieve rapid activation and curing of the self-adhesive layer through medium-frequency induction heating while maintaining pressure.

[0005] However, before the self-adhesive layer reaches a stable cured state, the silicon steel sheets still rely mainly on positioning fixtures and axial pressure to maintain their relative positions. During the lamination transfer, pressurization, rapid heating, and softening and flow of the self-adhesive layer, local changes in interlayer gaps, radial slippage, or circumferential rotation may occur. Simply increasing the axial pressure will increase the equipment load and may also lead to excessive extrusion of the adhesive layer or end-face deformation.

[0006] In the prior art, patent CN114160976B discloses a laser welding device for silicon steel sheets of motor stators. This device uses a pressing component to clamp the stator silicon steel sheets and a rotating component to rotate them, allowing the laser welding head to complete welding at different positions. This approach helps reduce repeated adjustments to the workpiece position during welding, improving the welding efficiency of the stator silicon steel sheets. However, this approach primarily achieves the connection of silicon steel sheets through localized fusion zones formed by laser welding, and its technical focus lies in the clamping, rotation, and multi-position welding of the silicon steel sheets. For small stator cores used in unmanned equipment, the silicon steel sheets are relatively thin, have an insulating layer on the surface, and require high precision in stacking dimensions and maintenance of magnetic properties. Therefore, it is still necessary to further control the welding range and localized heat input, and improve the overall connection between the layers of silicon steel sheets.

[0007] Patent CN116275510B discloses a four-station visual positioning laser welding device and method for motor stator silicon steel sheets. This solution, through a four-station feeding platform, pre-pressing assembly, laser welding assembly, and unloading assembly, enables stator silicon steel sheets to sequentially complete feeding, positioning, pre-pressing, welding, and unloading, featuring a high degree of automation and suitability for mass production. This solution primarily focuses on visual positioning, station switching, and laser welding production efficiency, resulting in a relatively large number of equipment components and station settings. For small stator silicon steel sheets used in unmanned equipment with self-adhesive coatings, in addition to welding position accuracy, the activation conditions of the self-adhesive layer, the axial pressure of the laminate, and the inter-sheet stability before heating and curing must also be considered. The aforementioned solution does not yet address the synergistic processing between induction heating of the self-adhesive layer, axial pressure curing, and local auxiliary laser welding on the outer circumference.

[0008] Another patent, CN110808670A, discloses an induction heating system and method for rapid curing of self-adhesive coated silicon steel cores. This method utilizes induction heating coils to heat silicon steel cores with self-adhesive coatings, and combines this with temperature detection and control devices to control the heating process, which helps improve the curing efficiency of the self-adhesive coating and shorten the core heating time. This technology mainly targets the rapid heating and curing of self-adhesive coated cores that have already formed stacks, focusing on the heating device and the curing process. For cases where small silicon steel sheets are stacked one by one, a stable overall connection has not yet been formed between the sheets before the self-adhesive layer completes thermal activation and curing. During transfer, pressurization, or heating, certain radial or angular offsets may occur. Therefore, before induction heating curing, suitable positioning, clamping, or position correction measures for small silicon steel sheets are still needed to reduce the risk of stack offset during transfer, pressurization, or heating.

[0009] Patent CN104716796A discloses a method for stacking self-adhesive silicon steel sheets for long stators. This method involves stacking, pressurizing, and heating silicon steel sheets with self-adhesive layers to create an adhesive bond between adjacent sheets. This reduces the impact of traditional mechanical connection structures on the silicon steel sheets and improves the overall connection between the stacked sheets. However, this solution primarily addresses long stator structures and their stacking and curing process, focusing on the heating and pressurizing of the self-adhesive silicon steel sheets. Stator cores for small drive motors used in unmanned equipment typically have small dimensions, a large number of stacked sheets, and a small tolerance range for positioning errors. Therefore, it is necessary to further consider the positioning stability during the stacking of individual silicon steel sheets, as well as the coordination between local connections and overall adhesion.

[0010] Existing pulsed laser microspot welding methods can identify the interfaces between adjacent laminations while maintaining the laminations in close contact, emitting laser pulses only at the lamination interfaces, thereby reducing melting and heat input in unwanted areas. However, existing pulsed laser joining schemes typically use welding as the primary connection method for stator laminations, without establishing a process coordination relationship between microspot welding and self-adhesive curing for laminations with thermally activated self-adhesive layers.

[0011] If circumferential welding is performed after the self-adhesive layer has fully cured, on the one hand, the local welding overlaps with the already formed interlayer adhesion in terms of connection function; on the other hand, the local high temperature generated by welding may affect the condition of adjacent self-adhesive layers and insulating layers. If a continuous weld seam is used that runs through the entire edge of the lamination, the range of electrical connection between the laminations may also be expanded.

[0012] Therefore, a composite connection scheme suitable for small stator cores of unmanned equipment needs to be proposed. Before the self-adhesive layer is cured, a small number of pulsed laser micro-dot connections are used to lock the position of the laminations. The welding range is limited by local uncoated anchoring areas, selective interface triggering, and intermittent weld point distribution. Subsequently, induction thermo-pressing curing is completed while keeping the laminations stable. The pulsed laser connection and the self-adhesive connection respectively undertake the functions of process anchoring, vibration redundancy, and interlayer surface connection. Summary of the Invention

[0013] The purpose of this invention is to provide a method and apparatus for pulsed laser pre-anchoring and induction self-adhesion of stator silicon steel sheets, which solves the problem that before the thermally activated self-adhesive layer is cured, the stator silicon steel sheet stack is prone to radial slippage, circumferential rotation or local interlayer gap changes during transfer, pressurization and induction heating. Furthermore, continuous through welding may expand the interlayer metal conduction area and the welding heat-affected zone.

[0014] To achieve the above objectives, the present invention provides a method for pulsed laser pre-anchoring and induction self-adhesion of stator silicon steel sheets, comprising the following steps: S1: Provide a plurality of stator silicon steel sheets, wherein at least one interlayer contact surface of the stator silicon steel sheet is provided with a thermally activated self-adhesive layer, and at least one local anchoring area is provided on the outer edge of the stator silicon steel sheet, wherein no self-adhesive layer is provided in the local anchoring area or the thickness of the self-adhesive layer is less than the thickness of the self-adhesive layer in the non-anchoring area. S2: The stator silicon steel sheets are sequentially transported to the positioning and stacking mechanism station in the device, and the stator silicon steel sheets are radially and circumferentially positioned. S3: Stack several stator silicon steel sheets one by one or in groups to form a stator silicon steel sheet stack, and determine whether the stator silicon steel sheet stack has reached the preset stack height. S4: After the stator silicon steel sheet stack reaches the preset stack height, the pressurizing mechanism applies axial preload to the stator silicon steel sheet stack to reduce the gap between adjacent stator silicon steel sheets. S5: While maintaining axial preload, the interface detection mechanism detects the laminated interface within the local anchoring zone and controls the pulsed laser pre-anchoring mechanism to form a local fusion zone that spans at least the selected laminated interface, with the selected laminated interface as the laser action center. Multiple local fusion zones constitute micro-point anchoring connection points. The micro-point anchoring connection points are spaced apart along the axial and / or circumferential directions of the stator silicon steel sheet laminate and do not form a continuous metal connection path that penetrates all laminated interfaces. S6: Maintain or adjust the axial pressure applied to the stator silicon steel sheet stack, and use an induction heating mechanism to heat the stator silicon steel sheet stack so that the self-adhesive layer is activated by heat and forms an interlayer surface connection between adjacent stator silicon steel sheets; S7: Adjust the induction heating state and axial pressure according to the temperature and pressure test results of the stator silicon steel sheet stack, and perform pressure holding and cooling shaping after reaching the activation and curing conditions that are compatible with the thermally activated self-adhesive layer. S8: Release the axial pressure and the testing agency will inspect the stacking status, micro-point anchoring connection status and self-adhesive connection status of the stator silicon steel sheet stack; S9: After passing the inspection, the stator core connection assembly for unmanned equipment is obtained.

[0015] Preferably, the local anchoring area is located at the outer edge of the stator silicon steel sheet yoke and in the outer edge region beyond the designed effective yoke thickness, or in the non-main magnetic flux concentration region determined by electromagnetic analysis; multiple local anchoring areas are arranged at circumferential intervals along the stator silicon steel sheet.

[0016] Preferably, the plurality of local anchoring zones are arranged circumferentially along the stator silicon steel sheets, and the micro-point anchoring connection points in each local anchoring zone are arranged axially. The axial positions of the micro-point anchoring connection points in different local anchoring zones are staggered from each other, so that no continuous metal connection path is formed through the entire lamination interface at any circumferential position.

[0017] Preferably, the local anchoring area is formed by at least one of coating masking, local laser removal, or mechanical removal.

[0018] Preferably, in step S5, at least one of a visual inspection device, a reflective optical sensor, a displacement sensor, or a laser profile detection device is used to identify the interface position between adjacent stator silicon steel sheets, and the control unit controls the pulsed laser pre-anchoring mechanism to emit laser pulses according to the identified interface position.

[0019] Preferably, in S6 and S7, at least one temperature detection position corresponds to the local anchoring area, and at least another temperature detection position corresponds to the non-anchored self-adhesive area; the control unit adjusts at least one of the following based on the temperature difference between the local anchoring area and the non-anchored self-adhesive area: induction heating power, induction heating frequency, heating time, or the relative position of the induction coil and the stator silicon steel sheet stack.

[0020] A stator silicon steel sheet pulsed laser pre-anchoring and induction self-adhesion device includes a feeding mechanism for outputting stator silicon steel sheets with a self-adhesive layer and a local anchoring area on the surface one by one. The positioning and stacking mechanism is used for radial positioning, circumferential positioning, and stacking of stator silicon steel sheets; The pressurizing mechanism is used to apply axial pressure to the stator silicon steel sheet stack that has reached the preset stacking height. An interface inspection mechanism is used to detect the position of the laminated interface within a local anchoring zone. The pulsed laser pre-anchoring mechanism is used to form a micro-point anchoring connection with the selected lamination interface as the laser action center under axial pressure. The induction heating mechanism is used to induction heat the stator silicon steel sheet stack that maintains axial pressure after pulsed laser pre-anchoring is completed, so that the self-adhesive layer is activated by heat. The testing mechanism is used to test the temperature and axial pressure of the stator silicon steel sheet stack, and to test at least one of the stack position, micro-point anchoring connection status, or self-adhesive connection status. The control unit is electrically connected to the feeding mechanism, positioning and stacking mechanism, pressurizing mechanism, interface detection mechanism, pulsed laser pre-anchoring mechanism, induction heating mechanism and detection mechanism, respectively.

[0021] Preferably, the feeding mechanism includes a material roll hopper, a slitting machine, and a vacuum adsorption assembly. The material roll hopper supplies raw materials to the slitting machine, which can produce stator silicon steel sheets. The vacuum adsorption assembly adsorbs the stator silicon steel sheets onto the work station of the positioning and stacking mechanism. The positioning and stacking mechanism includes an end face support platform and a positioning mandrel, a toothed positioning component, and an outer circle limiting component fixed on the end face support platform. The positioning mandrel is used to achieve radial positioning of the stator silicon steel sheet, the toothed positioning component is used to limit the circumferential angle of the stator silicon steel sheet, and the outer circle limiting component is used to assist in correcting the outer circle position. The pressurizing mechanism includes a pressure head, a hydraulic cylinder, a pressure sensor, and a displacement sensor. The fixed end of the hydraulic cylinder is fixed to a bracket, and the movable end of the hydraulic cylinder is vertically arranged with a pressure head at the end of the movable end for applying pressure to the stator silicon steel sheets. The pressure sensor detects the pressure, and the displacement sensor detects the height of multiple stator silicon steel sheets. The interface detection mechanism includes an industrial camera, a laser contour sensor, a reflective optical sensor, or a displacement sensor, used to identify the edges of silicon steel sheets and interlayer interfaces within the local anchoring area, and to send the interface position information to the control unit. The pulsed laser pre-anchoring mechanism includes a laser pulser, a laser welding head, a focusing component, a moving component, and a protective gas nozzle. The laser pulser output is equipped with a laser welding head. The moving component controls the overall movement of the stator silicon steel sheet. The control unit controls the laser welding head and laser pulse triggering based on the interface detection results, so that the laser pulse corresponds to the selected laminate interface. The protective gas output from the protective gas nozzle protects the stator silicon steel sheet. The induction heating mechanism includes an induction power supply, an induction coil, a temperature detection element one, and a temperature detection element two. The induction coil is located on the outer periphery or near the end face of the stator silicon steel sheet stack. Temperature detection element one and temperature detection element two are used to detect the temperature at different locations of the stator silicon steel sheet stack. The control unit adjusts the induction heating state according to the temperature difference between different locations. The induction power supply is used to provide energy to the induction coil. The testing mechanism includes a temperature detection component for detecting the temperature of the stator silicon steel sheet stack, a pressure sensor II for detecting axial pressure, as well as a height sensor, a flatness detection element, a vision inspection camera, and a connection strength detection component; the control unit adjusts the axial pressure, laser pulse triggering, laser energy, and induction heating status based on the test results.

[0022] Preferably, the interface detection mechanism and the pulsed laser pre-anchoring mechanism are spaced apart along the scanning direction of the local anchoring area. The control unit converts the position of the selected stacked interface into the corresponding laser action position based on the stacked interface position obtained by the interface detection mechanism and the relative positional relationship between the interface detection mechanism and the laser action position. The control unit triggers a laser pulse when the laser action position corresponds to the selected stacked interface.

[0023] Preferably, the control unit is configured to control the operation of each mechanism in the following sequence: positioning and stacking, axial pre-compression, stack interface detection, pulsed laser pre-anchoring, induction heating, pressure holding and curing of self-adhesive layer, and cooling and shaping.

[0024] The advantages and positive effects of the pulsed laser pre-anchoring and induction self-adhesion method for stator silicon steel sheets described in this invention are as follows: (1) The present invention changes the pulsed laser welding process from a repeated reinforcement process after bonding to a pre-anchoring process before self-adhesive curing, so that pulsed laser welding has a clear process necessity.

[0025] (2) By removing or thinning the self-adhesive layer in the local anchoring area, a more stable metal working surface can be provided for micro-spot welding, and the risk of laser directly acting on a large area of ​​adhesive layer can be reduced.

[0026] (3) By identifying the interface of the stacked pieces in the local anchoring area and triggering the laser pulse at the selected interface, the laser energy can be concentrated on the local area to be connected, reducing the laser effect and melting range of the non-connected area.

[0027] (4) Interval and staggered micro-point connections avoid forming a continuous metal connection path that runs through the entire laminate interface, which helps to limit the interlayer electrical conduction area and the range of welding heat-affected zone.

[0028] (5) Micro-point anchoring connection points can restrict the slippage of the stack during the softening and curing process of the self-adhesive layer, making the axial pressure and interlayer contact state more stable, which helps to improve the consistency of self-adhesive curing.

[0029] (6) The self-adhesive layer forms a large-area interlayer connection, which can bear the main shear load and provide a certain structural damping; the retained micro-point anchoring connection serves as local vibration resistance redundancy, which helps to adapt to the vibration, impact and frequent start-stop conditions of unmanned equipment.

[0030] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0031] Figure 1 This is a flowchart of a method for pulsed laser pre-anchoring and induction self-adhesion of stator silicon steel sheets according to the present invention; Figure 2 This is a schematic diagram of the stator silicon steel sheet structure with a local anchoring zone according to the present invention; Figure 3 This is a schematic diagram showing the staggered distribution of the micro-point anchoring connection points along the axial and circumferential directions of the stator silicon steel sheet stack according to the present invention. Figure 4 This is a schematic diagram of the feeding mechanism of the present invention; Figure 5 This is a schematic diagram of the positioning and stacking mechanism of the present invention; Figure 6 This is a schematic diagram of the pressurization mechanism of the present invention; Figure 7 This is a schematic diagram of the interface detection mechanism of the present invention; Figure 8 This is a schematic diagram of the pulsed laser pre-anchoring mechanism of the present invention; Figure 9 This is a schematic diagram of the induction heating mechanism of the present invention; Figure 10 This is a schematic diagram of the testing mechanism of the present invention.

[0032] Figure Labels 1. Feeding mechanism; 101. Material roll hopper; 102. Slitting machine; 103. Adsorption assembly; 2. Positioning and stacking mechanism; 201. Positioning mandrel; 202. Toothed positioning component; 203. Outer circle limiting component; 204. End face support platform; 3. Pressurization mechanism; 301. Hydraulic cylinder; 302. Pressure head; 303. Pressure sensor one; 304. Displacement sensor one; 4. Interface detection mechanism; 401. Industrial camera; 402. Laser contour sensor; 403. Displacement sensor II; 5. Pulsed laser pre-anchoring mechanism; 501. Laser pulser; 502. Laser welding head; 503. Protective gas nozzle; 6. Induction heating mechanism; 601. Induction power supply; 602. Temperature detection element one, temperature detection element two; 7. Testing mechanism; 701. Pressure sensor II; 702. Temperature detection assembly; 703. Flatness detection element; 704. Visual inspection camera; 705. Strength detection assembly; 706. Height sensor; 8. Stator silicon steel sheet; 801. Local anchoring zone; 802. Main magnetic flux concentration area; 803. Stator silicon steel sheet stack; 804. Micro-point anchoring connection point. Detailed Implementation

[0033] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0034] In this application, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. In case of any inconsistency, the meaning set forth in this specification or derived from the content described herein shall prevail. Furthermore, the terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit the scope of this application.

[0035] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0036] like Figures 1-10 As shown, a method for pulsed laser pre-anchoring and induction self-adhesion of stator silicon steel sheets includes the following steps: S1: Provide a plurality of stator silicon steel sheets 8, at least one interlayer contact surface of the stator silicon steel sheet 8 is provided with a thermally activated self-adhesive layer, and at least one local anchoring area 801 is provided on the outer edge of the stator silicon steel sheet 8, wherein no self-adhesive layer is provided in the local anchoring area 801 or the thickness of the self-adhesive layer is less than the thickness of the self-adhesive layer in the non-anchoring area.

[0037] Specifically, the stator silicon steel sheets are made of non-oriented electrical steel laminations.

[0038] S2: The stator silicon steel sheets 8 are sequentially transported to the positioning and stacking mechanism 2 in the device, and the stator silicon steel sheets 8 are radially and circumferentially positioned.

[0039] S3: Stack several stator silicon steel sheets 8 one by one or in groups to form a stator silicon steel sheet stack 803, and determine whether the stator silicon steel sheet stack 803 has reached the preset stacking height.

[0040] S4: After the stator silicon steel sheet stack 803 reaches the preset stack height, the pressurizing mechanism 3 applies axial preload to the stator silicon steel sheet stack 803 to reduce the gap between adjacent stator silicon steel sheets 8.

[0041] S5: While maintaining axial preload, the interface detection mechanism 4 detects the laminated interface within the local anchoring zone 801 and controls the pulsed laser pre-anchoring mechanism 5 to form a local fusion zone that at least spans the selected laminated interface, with the laser action center at the selected laminated interface. Multiple local fusion zones constitute micro-point anchoring connection points 804. The micro-point anchoring connection points 804 are spaced apart along the axial and / or circumferential directions of the stator silicon steel sheet laminate 803, and do not form a continuous metal connection path that penetrates all laminated interfaces.

[0042] S6: Maintain or adjust the axial pressure applied to the stator silicon steel sheet stack 803, and use the induction heating mechanism 6 to heat the stator silicon steel sheet stack 803, so that the self-adhesive layer is activated by heat and forms an interlayer surface connection between adjacent stator silicon steel sheets.

[0043] S7: Adjust the induction heating state and axial pressure according to the temperature and pressure test results of the stator silicon steel sheet laminate 803, and perform pressure holding and cooling shaping after reaching the activation and curing conditions that are compatible with the thermally activated self-adhesive layer.

[0044] S8: Release the axial pressure and the testing agency will inspect the stacking status, micro-point anchoring connection status and self-adhesive connection status of the stator silicon steel sheet laminate 803.

[0045] S9: After passing the inspection, the stator core connection assembly for unmanned equipment is obtained.

[0046] Local anchorage zones 801 are located at the outer edge of the stator silicon steel sheet yoke, in the outer edge region beyond the designed effective yoke thickness, or in the non-main magnetic flux concentration region 802 determined by electromagnetic analysis. Multiple local anchorage zones 801 are spaced apart circumferentially along the stator silicon steel sheet.

[0047] Multiple local anchoring zones 801 are spaced apart circumferentially along the stator silicon steel sheets, and micro-point anchoring connection points 804 within each local anchoring zone 801 are spaced apart axially. The axial positions of the micro-point anchoring connection points 804 within different local anchoring zones 801 are staggered, so that no continuous metal connection path is formed through the entire lamination interface at any circumferential position.

[0048] Specifically, the micro-anchor connection point 804 is not required to be formed at every lamination interface. A micro-anchor connection point 804 can be set at every one or more lamination interfaces, or the stator silicon steel sheet lamination 803 can be divided into multiple sub-laminated layers, with micro-anchor connection points 804 set at some interfaces between adjacent sub-laminated layers and within each sub-laminated layer. The local fusion zone formed by a single micro-anchor connection point 804 must span at least one selected lamination interface, and the continuous fusion range of this local fusion zone along the stack height direction must be less than the total height of the stator silicon steel sheet lamination.

[0049] The local anchoring zone 801 is formed by at least one of coating masking, local laser removal, or mechanical removal.

[0050] Specifically, S5 uses at least one of a visual inspection device, a reflective optical sensor, a displacement sensor, or a laser contour detection device to identify the interface position between adjacent stator silicon steel sheets, and the control unit controls the pulsed laser pre-anchoring mechanism 5 to emit laser pulses according to the identified interface position.

[0051] Specifically, in S6 and S7, at least one temperature detection position corresponds to the local anchoring area 801, and at least another temperature detection position corresponds to the non-anchored self-adhesive area. The control unit adjusts at least one of the following based on the temperature difference between the local anchoring area 801 and the non-anchored self-adhesive area: induction heating power, induction heating frequency, heating time, or the relative position of the induction coil and the stator silicon steel sheet stack 803.

[0052] Specifically, before formal pre-anchoring, a single-pulse step test is conducted using a calibration stack with the same material, thickness, coating condition, and clamping condition as the silicon steel sheets to be connected. The single-pulse energy, pulse width, or defocusing amount is adjusted step by step to determine the process window that allows the local fusion zone to stably bridging the selected interface, without observing spatter that affects the formation of the local fusion zone, and without forming a continuous through weld or melting beyond the predetermined number of layers. The formal pre-anchoring parameters are selected from this process window.

[0053] The present invention discloses a stator silicon steel sheet pulsed laser pre-anchoring and induction self-adhesion device, comprising a feeding mechanism 1 for outputting stator silicon steel sheets with a self-adhesive layer and a local anchoring area 801 on the surface one by one.

[0054] The positioning and stacking mechanism 2 is used for radial positioning, circumferential positioning and stacking of stator silicon steel sheets.

[0055] The pressurizing mechanism 3 is used to apply axial pressure to the stator silicon steel sheet stack 803 that has reached the preset stack height.

[0056] Interface detection mechanism 4 is used to detect the position of the laminated interface within the local anchoring zone 801.

[0057] The pulsed laser pre-anchoring mechanism 5 is used to form a micro-point anchoring connection with the selected lamination interface as the laser action center under axial pressure.

[0058] The induction heating mechanism 6 is used to induction heat the stator silicon steel sheet stack 803 that maintains axial pressure after the pulsed laser pre-anchoring is completed, so that the self-adhesive layer is activated by heat.

[0059] The testing agency is used to test the temperature and axial pressure of the stator silicon steel sheet stack 803, and to test at least one of the following: stack position, micro-point anchoring connection status, or self-adhesive connection status.

[0060] The control unit is electrically connected to the feeding mechanism 1, the positioning and stacking mechanism 2, the pressurizing mechanism 3, the interface detection mechanism 4, the pulsed laser pre-anchoring mechanism 5, the induction heating mechanism 6, and the detection mechanism, respectively.

[0061] The feeding mechanism 1 includes a material roll hopper 101, a slitting machine 102, and a vacuum adsorption assembly 103. The material roll hopper 101 supplies raw materials to the slitting machine 102, which can produce stator silicon steel sheets. The vacuum adsorption assembly 103 adsorbs the stator silicon steel sheets onto the work station of the positioning and stacking mechanism 2.

[0062] The positioning and stacking mechanism 2 includes an end face support platform 204 and a positioning mandrel 201, a toothed positioning component 202, and an outer circle limiting component 203 fixed on the end face support platform 204. The positioning mandrel 201 is used to achieve radial positioning of the stator silicon steel sheet, the toothed positioning component 202 is used to limit the circumferential angle of the stator silicon steel sheet, and the outer circle limiting component 203 is used to assist in correcting the outer circle position.

[0063] The pressurizing mechanism 3 includes a pressure head 302, a hydraulic cylinder 301, a pressure sensor 303, and a displacement sensor 304. The fixed end of the hydraulic cylinder 301 is fixed to a bracket, and the movable end of the hydraulic cylinder 301 is vertically arranged with a pressure head 302 attached to the end of the movable end for applying pressure to the stator silicon steel sheets. The pressure sensor 303 detects the pressure, and the displacement sensor 304 detects the height of multiple stator silicon steel sheets.

[0064] The interface detection mechanism 4 includes an industrial camera 401, a laser contour sensor 402, and a reflective optical sensor or displacement sensor 403, which are used to identify the edges of silicon steel sheets and interlayer interfaces within the local anchoring zone 801 and send the interface position information to the control unit.

[0065] The pulsed laser pre-anchoring mechanism 5 includes a laser pulser 501, a laser welding head 502, a focusing assembly, a moving assembly, and a protective gas nozzle 503. The laser welding head 502 is located at the output end of the laser pulser 501. The moving assembly controls the overall movement of the stator silicon steel sheets. The control unit controls the laser welding head 502 and laser pulse triggering based on interface detection results, ensuring the laser pulse corresponds to the selected laminated interface. The protective gas output from the protective gas nozzle 503 protects the stator silicon steel sheets.

[0066] The induction heating mechanism 6 includes an induction power supply 601, an induction coil, a first temperature detection element, and a second temperature detection element 602. The induction coil is located on the outer periphery or near the end face of the stator silicon steel sheet stack 803. The first and second temperature detection elements are used to detect the temperature at different locations on the stator silicon steel sheet stack 803. The control unit adjusts the induction heating state according to the temperature difference between different locations. The induction power supply 601 provides energy to the induction coil.

[0067] The testing mechanism includes a temperature detection component 702 for detecting the temperature of the stator silicon steel sheet laminate 803, a pressure sensor 701 for detecting axial pressure, a height sensor 706, a flatness detection element 703, a vision inspection camera 704, and a connection strength detection component 705. The control unit adjusts the axial pressure, laser pulse triggering, laser energy, and induction heating status based on the test results.

[0068] The interface detection mechanism 4 and the pulsed laser pre-anchoring mechanism 5 are arranged at intervals along the scanning direction of the local anchoring area 801. The control unit converts the position of the selected stacked interface into the corresponding laser action position according to the position of the stacked interface obtained by the interface detection mechanism 4 and the relative positional relationship between the interface detection mechanism 4 and the laser action position. When the laser action position corresponds to the selected stacked interface, the control unit triggers the laser pulse.

[0069] Specifically, the control unit is configured to control the operation of each mechanism in the following sequence: positioning and stacking, axial pre-compression, stack interface detection, pulsed laser pre-anchoring, induction heating, pressure holding and curing of self-adhesive layer, and cooling and shaping.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for pulsed laser pre-anchoring and induction self-adhesion of stator silicon steel sheets, characterized in that: Includes the following steps, S1: Provide a plurality of stator silicon steel sheets, wherein at least one interlayer contact surface of the stator silicon steel sheet is provided with a thermally activated self-adhesive layer, and at least one local anchoring area is provided on the outer edge of the stator silicon steel sheet, wherein no self-adhesive layer is provided in the local anchoring area or the thickness of the self-adhesive layer is less than the thickness of the self-adhesive layer in the non-anchoring area. S2: The stator silicon steel sheets are sequentially transported to the positioning and stacking mechanism station in the device, and the stator silicon steel sheets are radially and circumferentially positioned. S3: Stack several stator silicon steel sheets one by one or in groups to form a stator silicon steel sheet stack, and determine whether the stator silicon steel sheet stack has reached the preset stack height. S4: After the stator silicon steel sheet stack reaches the preset stack height, the pressurizing mechanism applies axial preload to the stator silicon steel sheet stack to reduce the gap between adjacent stator silicon steel sheets. S5: While maintaining axial preload, the interface detection mechanism detects the laminated interface within the local anchoring zone and controls the pulsed laser pre-anchoring mechanism to form a local fusion zone that spans at least the selected laminated interface, with the selected laminated interface as the laser action center. Multiple local fusion zones constitute micro-point anchoring connection points. The micro-point anchoring connection points are spaced apart along the axial and / or circumferential directions of the stator silicon steel sheet laminate and do not form a continuous metal connection path that penetrates all laminated interfaces. S6: Maintain or adjust the axial pressure applied to the stator silicon steel sheet stack, and use an induction heating mechanism to heat the stator silicon steel sheet stack so that the self-adhesive layer is activated by heat and forms an interlayer surface connection between adjacent stator silicon steel sheets; S7: Adjust the induction heating state and axial pressure according to the temperature and pressure test results of the stator silicon steel sheet stack, and perform pressure holding and cooling shaping after reaching the activation and curing conditions that are compatible with the thermally activated self-adhesive layer. S8: Release the axial pressure and the testing agency will inspect the stacking status, micro-point anchoring connection status and self-adhesive connection status of the stator silicon steel sheet stack; S9: After passing the inspection, the stator core connection assembly for unmanned equipment is obtained.

2. The method for pulsed laser pre-anchoring and induction self-adhesion of stator silicon steel sheets according to claim 1, characterized in that: The local anchoring zone is located at the outer edge of the stator silicon steel sheet yoke and is situated in the outer edge region beyond the designed effective yoke thickness, or in the non-main magnetic flux concentration region determined by electromagnetic analysis; multiple local anchoring zones are spaced apart along the circumference of the stator silicon steel sheet.

3. The method for pulsed laser pre-anchoring and induction self-adhesion of stator silicon steel sheets according to claim 2, characterized in that: Multiple local anchoring zones are arranged circumferentially along the stator silicon steel sheets, and micro-point anchoring connection points in each local anchoring zone are arranged axially. The axial positions of the micro-point anchoring connection points in different local anchoring zones are staggered, so that no continuous metal connection path is formed through the entire lamination interface at any circumferential position.

4. The method for pulsed laser pre-anchoring and induction self-adhesion of stator silicon steel sheets according to claim 1, characterized in that: The local anchoring zone is formed by at least one of coating masking, local laser removal, or mechanical removal.

5. The method for pulsed laser pre-anchoring and induction self-adhesion of stator silicon steel sheets according to claim 1, characterized in that: In S5, at least one of a visual inspection device, a reflective optical sensor, a displacement sensor, or a laser contour detection device is used to identify the interface position between adjacent stator silicon steel sheets. The control unit controls the pulsed laser pre-anchoring mechanism to emit laser pulses according to the identified interface position.

6. The method for pulsed laser pre-anchoring and induction self-adhesion of stator silicon steel sheets according to claim 1, characterized in that: In S6 and S7, at least one temperature detection position corresponds to the local anchoring area, and at least another temperature detection position corresponds to the non-anchored self-adhesive area; the control unit adjusts at least one of the following based on the temperature difference between the local anchoring area and the non-anchored self-adhesive area: induction heating power, induction heating frequency, heating time, or the relative position of the induction coil and the stator silicon steel sheet stack.

7. A stator silicon steel sheet pulsed laser pre-anchoring and induction self-adhesion device according to any one of claims 1-6, characterized in that: Includes a feeding mechanism for outputting stator silicon steel sheets with self-adhesive layers and local anchoring areas on the surface one by one; The positioning and stacking mechanism is used for radial positioning, circumferential positioning, and stacking of stator silicon steel sheets; The pressurizing mechanism is used to apply axial pressure to the stator silicon steel sheet stack that has reached the preset stacking height. An interface inspection mechanism is used to detect the position of the laminated interface within a local anchoring zone. The pulsed laser pre-anchoring mechanism is used to form a micro-point anchoring connection with the selected lamination interface as the laser action center under axial pressure. The induction heating mechanism is used to induction heat the stator silicon steel sheet stack that maintains axial pressure after pulsed laser pre-anchoring is completed, so that the self-adhesive layer is activated by heat. The testing mechanism is used to test the temperature and axial pressure of the stator silicon steel sheet stack, and to test at least one of the stack position, micro-point anchoring connection status, or self-adhesive connection status. The control unit is electrically connected to the feeding mechanism, positioning and stacking mechanism, pressurizing mechanism, interface detection mechanism, pulsed laser pre-anchoring mechanism, induction heating mechanism and detection mechanism, respectively.

8. The stator silicon steel sheet pulsed laser pre-anchoring and induction self-adhesion device according to claim 7, characterized in that: The feeding mechanism includes a material roll hopper, a slitting machine, and a vacuum adsorption assembly. The material roll hopper supplies raw materials to the slitting machine, which can produce stator silicon steel sheets. The vacuum adsorption assembly adsorbs the stator silicon steel sheets onto the work station of the positioning and stacking mechanism. The positioning and stacking mechanism includes an end face support platform and a positioning mandrel, a toothed positioning component, and an outer circle limiting component fixed on the end face support platform. The positioning mandrel is used to achieve radial positioning of the stator silicon steel sheet, the toothed positioning component is used to limit the circumferential angle of the stator silicon steel sheet, and the outer circle limiting component is used to assist in correcting the outer circle position. The pressurizing mechanism includes a pressure head, a hydraulic cylinder, a pressure sensor, and a displacement sensor. The fixed end of the hydraulic cylinder is fixed to a bracket, and the movable end of the hydraulic cylinder is vertically arranged with a pressure head at the end of the movable end for applying pressure to the stator silicon steel sheets. The pressure sensor detects the pressure, and the displacement sensor detects the height of multiple stator silicon steel sheets. The interface detection mechanism includes an industrial camera, a laser contour sensor, a reflective optical sensor, or a displacement sensor, used to identify the edges of silicon steel sheets and interlayer interfaces within the local anchoring area, and to send the interface position information to the control unit. The pulsed laser pre-anchoring mechanism includes a laser pulser, a laser welding head, a focusing component, a moving component, and a protective gas nozzle. The laser pulser output is equipped with a laser welding head. The moving component controls the overall movement of the stator silicon steel sheet. The control unit controls the laser welding head and laser pulse triggering based on the interface detection results, so that the laser pulse corresponds to the selected laminate interface. The protective gas output from the protective gas nozzle protects the stator silicon steel sheet. The induction heating mechanism includes an induction power supply, an induction coil, a temperature detection element one, and a temperature detection element two. The induction coil is located on the outer periphery or near the end face of the stator silicon steel sheet stack. Temperature detection element one and temperature detection element two are used to detect the temperature at different locations of the stator silicon steel sheet stack. The control unit adjusts the induction heating state according to the temperature difference between different locations. The induction power supply is used to provide energy to the induction coil. The testing mechanism includes a temperature detection component for detecting the temperature of the stator silicon steel sheet stack, a pressure sensor II for detecting axial pressure, as well as a height sensor, a flatness detection element, a vision inspection camera, and a connection strength detection component; the control unit adjusts the axial pressure, laser pulse triggering, laser energy, and induction heating status based on the test results.

9. The stator silicon steel sheet pulsed laser pre-anchoring and induction self-adhesion device according to claim 8, characterized in that: The interface detection mechanism and the pulsed laser pre-anchoring mechanism are spaced apart along the scanning direction of the local anchoring area. The control unit converts the position of the selected stacked interface into the corresponding laser action position based on the position of the stacked interface obtained by the interface detection mechanism and the relative positional relationship between the interface detection mechanism and the laser action position. When the laser action position corresponds to the selected stacked interface, a laser pulse is triggered.

10. The apparatus in the pulsed laser pre-anchoring and inductive self-adhesion method for stator silicon steel sheets according to claim 9, characterized in that: The control unit is configured to control the operation of each mechanism in the following sequence: positioning and stacking, axial pre-compression, stack interface detection, pulsed laser pre-anchoring, induction heating, pressure holding and curing of self-adhesive layer, and cooling and shaping.

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