Permanent magnet synchronous motor iron core welding device

Abstract

The invention discloses a permanent magnet synchronous motor iron core welding device, and relates to the technical field of iron core welding, the permanent magnet synchronous motor iron core welding device comprises a rack, a welding platform is arranged in the rack, a welding manipulator is arranged right above the welding platform, and a laser welding gun main body is mounted at the end part of the welding manipulator; an auxiliary mechanism capable of synchronously moving along with the laser welding gun body from bottom to top is installed on the outer surface of the laser welding gun body, and the auxiliary mechanism can enable silicon steel sheet layers in a local area to have instant micro gaps before welding operation so as to promote molten liquid to permeate into a deep layer. And after welding is completed, axial downward pressure is applied to the area so as to compact the welding seam and increase the compactness between the silicon steel sheet layers, local pressure release of the welding area is achieved through a double-layer pressing plate and an annular pressing rod, continuous operation of gap pre-expansion, melt permeation and welding seam compaction is constructed in cooperation with a Y-shaped push rod and a pressing wheel, melt permeation and the compactness between the layers are taken into consideration, and the welding quality is improved. The iron core welding quality is improved.

Description

Technical Field

[0001] This invention relates to the field of iron core welding technology, specifically to a welding device for the iron core of a permanent magnet synchronous motor. Background Technology

[0002] The core of a permanent magnet synchronous motor, as the core component of the motor's magnetic circuit, is made of multiple layers of silicon steel sheets. Its connection technology directly determines the motor's mechanical strength, electromagnetic performance, and operational reliability. During the motor assembly process, in order to prevent relative displacement, vibration, or loosening between the laminations, it is often necessary to weld and fix the ends of the core to form an integral structure. Currently, commonly used welding methods include laser welding, resistance welding, and brazing. Among them, laser welding has become the mainstream process due to its concentrated energy, small heat-affected zone, and high precision. Currently, traditional laser welding equipment mainly consists of a frame, laser welding gun, welding worktable, and control system. The frame serves as the basic support structure of the equipment, supporting the various components and ensuring overall stability. The welding robotic arm typically has multi-axis motion capabilities, driving the laser welding gun to move in three-dimensional space to achieve precise welding of welding slots at different positions on the iron core. The laser welding gun, as the core execution component, is responsible for focusing the high-energy laser beam onto the welding area, causing the material to melt instantly and form a weld. However, in traditional laser welding processes for iron cores, in order to ensure the overall structural stability of the iron core and prevent relative slippage, vibration, or loosening of the silicon steel sheets in each layer during processing and operation, an axial limiting mechanism is generally used to apply a large axial clamping force to the stacked sheets. Under the application of axial limiting pressure, the silicon steel sheets are forced to fit tightly together, and the interlayer connection is too tight. At high temperatures, liquid metal should diffuse to the root of the weld and between layers by relying on surface tension and capillary action, but due to the lack of sufficient penetration channels, the molten metal can only spread on the surface and is difficult to penetrate downwards to fill the gaps. This can easily lead to problems such as incomplete welding and false welding between layers, which affects the structural strength of the iron core.

[0003] To address the aforementioned problems, this invention proposes a permanent magnet synchronous motor core welding device that creates instantaneous micro-gaps between silicon steel sheet layers in a localized area before welding to promote molten metal penetration, and simultaneously applies axial pressure to the area after welding to compact the weld. Summary of the Invention

[0004] The present invention addresses the problem of overly simplistic solutions in existing technologies by providing a significantly different solution. Specifically, the present invention aims to provide a permanent magnet synchronous motor core welding device to solve the problem mentioned in the background art where traditional welding equipment is prone to interlayer incomplete welding and false welding, which affects the structural strength of the core.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a permanent magnet synchronous motor core welding device, comprising a frame, a welding platform disposed inside the frame, a welding robot disposed directly above the welding platform, a laser welding gun body mounted at the end of the welding robot, and an auxiliary mechanism mounted on the outer surface of the laser welding gun body that can move synchronously from bottom to top with the laser welding gun body. The auxiliary mechanism can create instantaneous micro-gap between silicon steel sheet layers in a local area before welding, so as to promote the penetration of molten liquid into the deeper layers, and apply axial downward pressure to the area after welding to compact the weld and increase the tightness between silicon steel sheet layers. The upper surface of the welding platform is equipped with a three-jaw chuck, and the inside of the frame is equipped with a positioning mechanism that can apply axial downward pressure to the iron core body.

[0006] Preferably, a turntable is rotatably connected inside the frame, and a cylinder for connecting a positioning mechanism is fixedly installed in the middle of the lower surface of the turntable, and the edge of the lower surface of the turntable is fixedly connected to the base of the welding robot. The positioning mechanism includes a main shaft rotatably connected to the piston rod of the cylinder, and an annular fixing frame is fixedly connected to the lower end face of the main shaft. Several sets of double-layer pressure plates are installed at the bottom of the annular fixing frame.

[0007] Preferably, the double-layer pressure plate includes an upper pressure plate and a lower pressure plate, which are fixedly connected by a plurality of pressure springs. Each pressure spring has a shaft sleeved inside, one end of which is fixedly connected to the lower pressure plate, and the other end of which passes through the upper pressure plate and is fixedly connected to the lower surface of the annular fixing frame.

[0008] Preferably, two hydraulic rods are rotatably connected to the outer wall of the main shaft, and the piston rod of the hydraulic rod is fixedly connected to a rotating frame. The rotating frame is sleeved on the outside of the main shaft, and an annular pressure rod is fixedly connected to the lower surface of the rotating frame through a connecting rod. The outer wall of the rotating frame is rotatably connected to the outer wall of the welding robot through a telescopic rod.

[0009] Preferably, a pressure block is fixedly connected to the upper surface of each upper pressure plate, and the pressure block is provided with a sliding groove for the sliding of the annular pressure rod, and one section of the annular pressure rod is designed to be wavy.

[0010] Preferably, the auxiliary mechanism includes a fixing plate fixedly connected to the outer surface of the laser welding gun body, a Y-shaped push rod fixedly connected to the front end of the fixing plate, and two abutting blocks abutting against the inner wall of the iron core welding groove fixedly connected to the front end of the Y-shaped push rod, and the outer surface of the two abutting blocks is provided with several protrusions.

[0011] Preferably, the rear ends of the fixing plate are connected to two pressure rollers by two connecting rods, and a gear assembly is installed on the outer side of one of the connecting rods.

[0012] Preferably, the pressure roller includes an inner hub and an outer silicone sleeve, and the two inner hubs are fixedly connected by a rotating shaft. The two ends of the rotating shaft are rotatably connected to two connecting rods respectively through two bearings. The gear assembly includes a large gear fixedly inserted into one end of a rotating shaft, a small gear meshing with one side of the large gear, and an output shaft of a drive motor fixedly inserted into the inner wall of the small gear.

[0013] Compared with the prior art, the beneficial effects of the present invention are: This invention achieves overall axial pre-tightening of the iron core by driving a double-layer pressure plate with a cylinder. In conjunction with a hydraulic rod, it drives the annular pressure rod to rotate. By utilizing the precise fit between its wavy section and the curved sliding groove of the pressure block, it achieves local pressure release in the welding area and instantaneous pressure increase and compaction after welding. The non-welding area maintains stable pressure at all times. This not only creates microscopic gaps between layers for molten metal penetration, but also avoids overall iron core stacking instability. At the same time, the curved sliding groove design greatly reduces the scraping friction of mechanical movement and improves the smoothness and accuracy of pressure control. This invention integrates the dual functions of welding groove calibration and interlayer micro-gap pre-expansion by adding an upwardly tilted Y-shaped push rod front auxiliary structure. The abutment block of the Y-shaped push rod is pre-embedded in the welding groove. When the welding torch moves from bottom to top, the friction between the surface protrusion and the inner wall of the welding groove generates a slight upward thrust, which further expands the instantaneous interlayer micro-gap generated by the pressure release of the positioning mechanism, reserving sufficient channels for deep penetration of the molten metal. At the same time, the abutment block dynamically calibrates the welding groove with circumferential misalignment during the movement process, and eliminates the interlayer groove deviation through lateral extrusion force, so that the welding groove of the multilayer silicon steel sheet forms a continuous and straight trajectory, ensuring that the molten metal penetrates evenly into the inner layer of the silicon steel sheet along the calibrated groove. This invention achieves active, dynamic, and uniform compaction of the weld seam through a pressure roller. The pressure roller moves synchronously with the welding torch, generating a stable and uniform downward extrusion force that crushes the silicon steel sheets on both sides of the weld seam. This assists in further filling and expelling air bubbles from the interlayer molten metal. The entire auxiliary mechanism is rigidly connected to the main body of the laser welding torch, achieving a seamless connection between the pre-expansion gap of the abutment block, precise laser welding, and immediate compaction by the pressure roller. This creates a continuous operation of pre-expansion gap, molten metal penetration, and weld seam compaction, significantly improving the weld seam penetration rate and interlayer bonding strength, and effectively reducing welding defects such as porosity and cracks. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0015] Figure 2 This is a schematic diagram of the welding platform and welding robot of the present invention.

[0016] Figure 3 This is a schematic diagram of the positioning mechanism of the present invention.

[0017] Figure 4 This is a schematic diagram of the exploded structure of the positioning mechanism of the present invention.

[0018] Figure 5 This is a schematic diagram of the structure after the wavy section of the annular pressure bar of the present invention comes into contact with the pressure block.

[0019] Figure 6 This is a schematic diagram of the exploded structure of the double-layer pressure plate of the present invention.

[0020] Figure 7 This is a schematic diagram of the auxiliary mechanism structure of the present invention.

[0021] Figure 8 This is a schematic diagram of the auxiliary mechanism of the present invention from another angle.

[0022] Figure 9 This is a side view of the pressure roller of the present invention after it comes into contact with the surface of the iron core body.

[0023] In the diagram: 1. Frame; 2. Welding platform; 3. Welding robot; 4. Laser welding gun body; 5. Auxiliary mechanism; 501. Fixing plate; 502. Y-shaped push rod; 503. Abutment block; 504. Connecting rod; 505. Inner hub; 506. Outer silicone sleeve; 507. Rotating shaft; 508. Large gear; 509. Small gear; 5010. Drive motor; 6. Three-jaw chuck; 7. Positioning mechanism; 701. Main shaft; 702. Annular fixing frame; 703. Upper pressure plate; 704. Lower pressure plate; 705. Pressure spring; 706. Shaft; 707. Hydraulic rod; 708. Rotating frame; 709. Annular pressure rod; 7010. Pressure block; 8. Turntable; 9. Cylinder; 10. Telescopic rod. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Please see Figures 1 to 9The present invention provides a technical solution: a permanent magnet synchronous motor core welding device, including a frame 1, a welding platform 2 is arranged inside the frame 1, a welding robot 3 is arranged directly above the welding platform 2, a laser welding gun body 4 is installed at the end of the welding robot 3, and an auxiliary mechanism 5 is installed on the outer surface of the laser welding gun body 4, which can move synchronously from bottom to top with the laser welding gun body 4. The auxiliary mechanism 5 can make instantaneous micro gaps appear between the silicon steel sheet layers in a local area before the welding operation, so as to promote the molten liquid to penetrate into the deeper layer, and apply axial downward pressure to the area after welding to compact the weld and increase the tightness between the silicon steel sheet layers. The upper surface of the welding platform 2 is equipped with a three-jaw chuck 6, and the inside of the frame 1 is equipped with a positioning mechanism 7, which can apply axial downward pressure to the iron core body. The three-jaw chuck 6 fixes the bottom inner wall of the iron core body to achieve radial positioning of the iron core body and prevents horizontal displacement of the iron core during welding. At the same time, the positioning mechanism 7 drives the main shaft 701 to move downward through the cylinder 9 to apply uniform and continuous axial downward pressure to the iron core body to ensure that the iron core always maintains a stacked state during welding and avoids interlayer separation due to thermal deformation. In addition, during the welding process, the auxiliary mechanism 5 is directly mounted on the outer surface of the laser welding gun body 4 and can move from bottom to top along the welding groove of the iron core body synchronously with the welding gun. During the welding process, the auxiliary mechanism 5 creates controllable micro gaps between the layers of silicon steel sheets, providing a channel for the molten base material to penetrate into the depth of the welding groove, reducing the risk of the molten base material being lost due to gravity, and promoting the full filling of the molten liquid into the depth of the welding groove and between the silicon steel sheets. After the welding is completed, axial downward pressure is immediately applied to compact the weld and increase the tightness between the silicon steel sheets, further improving the weld penetration rate and interlayer bonding strength. In this embodiment, as Figure 1 and Figure 2 As shown, a turntable 8 is rotatably connected inside the frame 1. A cylinder 9 for connecting the positioning mechanism 7 is fixedly installed in the middle of the lower surface of the turntable 8. The lower surface edge of the turntable 8 is fixedly connected to the base of the welding robot 3. The positioning mechanism 7 includes a main shaft 701 that is rotatably connected to the piston rod of the cylinder 9. A ring-shaped fixing frame 702 is fixedly connected to the lower end face of the main shaft 701. Several sets of double-layer pressure plates are installed at the bottom of the ring-shaped fixing frame 702. It should be noted that the turntable 8 is rotatably connected to the top of the inner wall of the frame 1. A control system is also installed inside the frame 1 to drive the turntable 8 to rotate and the welding robot 3 to adjust its position. When the turntable 8 rotates under the drive of the control system, it can synchronously drive the welding robot 3 to rotate circumferentially around the three-jaw chuck 6 and the outer circumference of the iron core body fixed above the three-jaw chuck 6, thereby realizing the welding operation of welding slots at different circumferential positions of the iron core. It is not necessary to frequently adjust the fixed position of the iron core, which improves the welding efficiency. The control steps of this control system belong to the prior art. The cylinder 9 serves as the driving source for the positioning mechanism 7. The extension and retraction of its piston rod can drive the main shaft 701 and the entire positioning mechanism 7 to move up and down, so as to accurately press the double-layer pressure plate onto the upper surface of the iron core body before welding. After welding, the positioning mechanism 7 is lifted up to facilitate the removal and placement of the iron core body.

[0026] In this embodiment, as Figures 3 to 6 As shown, the double-layer pressure plate includes an upper pressure plate 703 and a lower pressure plate 704. The upper pressure plate 703 and the lower pressure plate 704 are fixedly connected by several pressure springs 705. Each pressure spring 705 has a shaft 706 sleeved inside. One end of the shaft 706 is fixedly connected to the lower pressure plate 704, and the other end of the shaft 706 passes through the upper pressure plate 703 and is fixedly connected to the lower surface of the annular fixing frame 702. Two hydraulic rods 707 are rotatably connected to the outer wall of the main shaft 701. The piston rod of the hydraulic rod 707 is fixedly connected to a rotating frame 708. The rotating frame 708 is sleeved on the outside of the main shaft 701. The lower surface of the rotating frame 708 is fixedly connected to an annular pressure rod 709 through a connecting rod. The outer wall of the rotating frame 708 is rotatably connected to the outer wall of the welding robot 3 through a telescopic rod 10. Each upper plate 703 has a pressure block 7010 fixedly connected to its upper surface. The pressure block 7010 has a groove for sliding the annular pressure rod 709. One section of the annular pressure rod 709 is wavy. It should be noted that when the cylinder 9 drives the main shaft 701 to move the annular fixed frame 702 downward, the annular fixed frame 702 will drive all the double-layer pressure plates and the annular pressure rod 709 to move downward simultaneously, axially limiting the upper surface of the iron core body. During the limiting process, the lower pressure plate 704 first contacts the upper surface of the iron core body, and then the hydraulic rod 707 is activated at the same time. The piston rod of the hydraulic rod 707 extends further, pushing the rotating frame 708 to move downward further, thereby driving the annular pressure rod 709 to move downward along the pressure block 7010, generating a downward squeezing force on the upper pressure plate 703. This pressure is transmitted to the pressure spring 705 through the upper pressure plate 703, causing the pressure spring 705 to be further compressed, thereby driving the lower pressure plate 704 to apply greater local pressure to the iron core body, ensuring that the axial pressure applied to the iron core body is uniform and has buffering properties, avoiding damage to the iron core surface caused by rigid contact; In addition, one section of the annular pressure bar 709 is made into a wave shape. Except for this wave-shaped section, all other areas are on the same horizontal plane. The wave-shaped section of the annular pressure bar 709 is mainly divided into a crest section and a trough section. The crest section is aligned with the telescopic rod 10. The telescopic rod 10 is used to connect the outer wall of the welding robot 3. When the welding robot 3 rotates, it will drive the rotating frame 708 to rotate synchronously through the telescopic rod 10, thereby causing the annular pressure bar 709 to rotate. The welding robot 3 is mainly composed of a large arm and a small arm. The laser welding gun body 4 is installed at the end of the small arm. Through the cooperation of the large arm and the small arm, the laser welding gun body 4 can be driven to move from bottom to top along the welding groove of the iron core body. One end of the telescopic rod 10 is rotatably connected to the outer wall of the large arm of the welding robot 3, and the other end is rotatably connected to the outer wall of the rotating frame 708. When the large arm of the welding robot 3 rotates, it will push or pull the rotating frame 708 to rotate around the main shaft 701 through the telescopic rod 10, thereby driving the annular pressure rod 709 to slide in the groove of the pressure block 7010. Through the connection of the telescopic rod 10, the telescopic rod 10 is appropriately adjusted during the up and down movement of the laser welding gun body 4. This ensures that the annular pressure rod 709 rotates and moves synchronously with the laser welding gun body 4, without interfering with the normal up and down movement of the welding robot 3. By using the annular pressure rod 709 to follow the synchronous rotation of the welding robot 3, the pressure on the local welding area is released. Specifically, when the laser welding gun body 4 welds a certain welding groove, the crest section of the annular pressure rod 709 rotates to the position of the pressure block 7010 directly above the corresponding welding groove. When the crest section contacts the corresponding pressure block 7010, the crest section can accommodate the pressure block 7010 to move further upward, which reduces the compression of the pressure spring 705 at the corresponding position. The local pressure on the iron core body in this area is reduced accordingly, thereby reducing the axial pressure in the welding area. This causes a small instantaneous micro gap to be generated between the silicon steel sheets in the welding area due to the reduced pressure, creating conditions for subsequent molten metal penetration. Meanwhile, the pressure blocks 7010 in other non-welding areas are in contact with the remaining section of the annular pressure rod 709. The pressure spring 705 maintains a large compression and continues to apply stable axial pressure to the iron core, ensuring that the silicon steel sheets in the non-welding areas remain tightly fitted and avoiding the impact on the overall stacking stability of the iron core due to the reduction of local pressure. In this embodiment, the number of double-layer pressure plates is matched with the number of welding slots. In other embodiments, when the number of welding slots is adjusted, the number of double-layer pressure plates can also be increased or decreased to meet the welding requirements of iron cores of different specifications. Similarly, after the welding in this area is completed, the turntable 8 drives the welding robot 3 to rotate again, which in turn drives the annular pressure bar 709 to rotate synchronously. When the trough section of the annular pressure bar 709 gradually contacts the previously corresponding pressure block 7010, the downward pressure on the pressure block 7010 increases, and the pressure spring 705 at the corresponding position is further compressed, increasing the pressure, even more than the original pressure. By increasing the pressure in this area, the weld that has just been welded is further compacted, further promoting the densification of the molten metal during solidification, reducing the generation of defects such as porosity and cracks, effectively improving the mechanical strength and interlayer bonding of the weld. After a short period of compaction, the trough section will rotate and move away, and the pressure block 7010 will re-contact the planar section of the annular pressure bar 709, and the pressure will return to the stable state during normal welding. In addition, it should be noted that the groove on the inner wall of the pressure block 7010 is a curved surface. The inner wall of the curved surface has no sharp edges. When it connects to the wavy section of the annular pressure rod 709, it reduces scratches and friction. Furthermore, when connecting to the crest section, the crest of the annular pressure rod 709 can better fit with the inner wall of the curved surface, avoiding jamming or tilting.

[0027] In this embodiment, as Figures 7 to 9 As shown, the auxiliary mechanism 5 includes a fixing plate 501 fixedly connected to the outer surface of the laser welding gun body 4. A Y-shaped push rod 502 is fixedly connected to the front end of the fixing plate 501. Two abutting blocks 503 that abut against the inner wall of the iron core welding groove are fixedly connected to the front end of the Y-shaped push rod 502. The outer surfaces of the two abutting blocks 503 are provided with several protrusions. The rear ends of the fixed plate 501 are connected to two pressure rollers by two connecting rods 504 on both sides, and a gear assembly is installed on the outer side of one of the connecting rods 504. The pressure roller includes an inner hub 505 and an outer silicone sleeve 506. The two inner hubs 505 are fixedly connected by a rotating shaft 507. The two ends of the rotating shaft 507 are rotatably connected to two connecting rods 504 respectively through two bearings. The gear assembly includes a large gear 508 that is fixedly inserted into one end of a rotating shaft 507, a small gear 509 that meshes with one side of the large gear 508, and the output shaft of a drive motor 5010 that is fixedly inserted into the inner wall of the small gear 509. It should be noted that the auxiliary mechanism 5 is rigidly connected to the laser welding gun body 4 through the fixing plate 501. One end of the laser welding gun body 4 passes through the middle of the fixing plate 501 and is aligned with the welding groove, while the other end is connected to the end of the forearm of the welding robot 3. In this case, the two abutment blocks 503 at the front end of the Y-shaped push rod 502 of the fixed plate 501 are embedded in the welding groove of the iron core before welding begins. The Y-shaped push rod 502 is tilted upward, and the several protrusions on the outer surface of the abutment block 503 can increase the friction with the silicon steel sheet on the inner wall of the welding groove. When the laser welding gun body 4 moves from bottom to top, the abutment block 503 of the Y-shaped push rod 502 will pass through the welding area before the laser welding gun body 4. The protrusions on its surface will generate a slight upward pushing force on the silicon steel sheet on both sides of the inner wall of the welding groove. On the one hand, the pushing force can make the silicon steel sheet in this area form a slight upward trend, further expanding the instantaneous micro gap between layers and providing more space for molten liquid penetration. On the other hand, the two abutment blocks 503 can also be used to further calibrate the original welding groove when they move along the welding groove. Specifically, the abutment block 503 moves upward from the starting end at the bottom of the welding groove. If there is circumferential misalignment of the laminated silicon steel sheets, the side wall of the abutment block 503 will exert a transverse extrusion force on the inner wall of the welding groove, forcing the misaligned silicon steel sheets to rotate or translate slightly, further eliminating the groove deviation between layers, aligning the welding groove axes of the multilayer silicon steel sheets, forming a continuous and straight welding trajectory, avoiding the subsequent weld seam of the laser welding gun from shifting, and allowing the welding groove to maintain trajectory consistency while forming micro gaps, ensuring that the molten liquid penetrates evenly into the inner layer along the calibrated groove. In addition, it should be noted that the three jaws of the three-jaw chuck 6 are stepped jaws. When fixing the inner wall of the iron core body, the lower surface of the iron core body is placed on the stepped surface of the jaws of the three-jaw chuck 6 to achieve the initial positioning of the iron core body. At the same time, the iron core body is clamped and fixed from the inner wall by the radial outward movement of the jaws. There is a gap between the iron core body and the bottom chuck of the three-jaw chuck 6 to reserve space for the auxiliary mechanism 5. Furthermore, a groove is provided on the outer side of the double-layer pressure plate to ensure that the pressure roller of the auxiliary mechanism 5 can smoothly enter from the beginning of the welding groove, move upward to the top, and finally pass through the groove of the double-layer pressure plate to complete the auxiliary operation of the entire welding groove surface. In addition, after welding is completed, the two pressure rollers at the rear end of the fixed plate 501 immediately apply axial downward pressure to the newly formed weld area. The drive motor 5010 drives the rotating shaft 507 and the inner hub 505 to rotate through the meshing of the small gear 509 and the large gear 508. The outer silicone sleeve 506 rotates synchronously and in a counterclockwise direction. The rotation tangent direction of the area in contact with the weld is downward, which will generate a stable and uniform downward extrusion force. The speed is faster than the upward movement speed of the laser welding body, so that the outer silicone sleeve 506 forms an active rolling friction with the weld surface. The outer silicone sleeve 506 is designed as an annular sealing structure and filled with hydraulic oil. When the pressure roller contacts the weld surface, once the inner side comes into contact with the silicon steel sheet during the rolling process, the contact point will generate local extrusion force on the silicone sleeve. This forces the internal hydraulic oil to flow adaptively along the sealing cavity, from the pressurized area to the unpressurized area. This causes the side wall of the outer silicone sleeve 506 to deform synchronously, generating a certain axial downward extrusion force while avoiding excessive local pressure that could damage the weld. The downward extrusion force crushes the silicon steel sheets on both sides of the weld, assisting the interlayer melt to further fill and expel air bubbles. Throughout the welding process, the abutment block 503 and pressure roller of the auxiliary mechanism 5 move synchronously with the laser welding gun body 4. The abutment block 503, located in front of the laser welding gun body 4, creates a channel for molten metal penetration through friction and thrust against the inner wall of the welding groove via a protruding strip. The pressure roller follows closely behind, applying precise downward pressure to the newly welded high-temperature weld. In the early stage of molten metal solidification, active rolling friction promotes densification, effectively solving the problems of insufficient molten metal penetration and weak interlayer bonding in traditional welding, and significantly improving the welding quality and structural stability of the permanent magnet synchronous motor core.

[0028] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A permanent magnet synchronous motor core welding device, comprising a frame (1), wherein a welding platform (2) is provided inside the frame (1), and a welding robot (3) is provided directly above the welding platform (2), wherein a laser welding gun body (4) is installed at the end of the welding robot (3), characterized in that: The outer surface of the laser welding gun body (4) is equipped with an auxiliary mechanism (5) that can move synchronously from bottom to top with the laser welding gun body (4). The auxiliary mechanism (5) can make instantaneous micro gaps appear between the silicon steel sheet layers in a local area before the welding operation, so as to promote the molten liquid to penetrate into the deeper layer, and apply axial downward pressure to the area after welding to compact the weld and increase the tightness between the silicon steel sheet layers. The upper surface of the welding platform (2) is equipped with a three-jaw chuck (6), and the inside of the frame (1) is provided with a positioning mechanism (7), which can apply axial downward pressure to the iron core body.

2. The permanent magnet synchronous motor core welding device according to claim 1, characterized in that: The frame (1) is rotatably connected to a turntable (8). A cylinder (9) for connecting a positioning mechanism (7) is fixedly installed in the middle of the lower surface of the turntable (8). The lower surface edge of the turntable (8) is fixedly connected to the base of the welding robot (3). The positioning mechanism (7) includes a main shaft (701) rotatably connected to the piston rod of the cylinder (9). A ring-shaped fixing frame (702) is fixedly connected to the lower end face of the main shaft (701). Several sets of double-layer pressure plates are installed at the bottom of the ring-shaped fixing frame (702).

3. The permanent magnet synchronous motor core welding device according to claim 2, characterized in that: The double-layer pressure plate includes an upper pressure plate (703) and a lower pressure plate (704). The upper pressure plate (703) and the lower pressure plate (704) are fixedly connected by several pressure springs (705). Each pressure spring (705) has a shaft (706) sleeved inside. One end of the shaft (706) is fixedly connected to the lower pressure plate (704), and the other end of the shaft (706) passes through the upper pressure plate (703) and is fixedly connected to the lower surface of the annular fixing frame (702).

4. The permanent magnet synchronous motor core welding device according to claim 2, characterized in that: Two hydraulic rods (707) are rotatably connected to the outer wall of the main shaft (701). The piston rod of the hydraulic rod (707) is fixedly connected to a rotating frame (708). The rotating frame (708) is sleeved on the outside of the main shaft (701). The lower surface of the rotating frame (708) is fixedly connected to an annular pressure rod (709) through a connecting rod. The outer wall of the rotating frame (708) is rotatably connected to the outer wall of the welding robot (3) through a telescopic rod (10).

5. The permanent magnet synchronous motor core welding device according to claim 3, characterized in that: Each of the upper pressure plates (703) has a pressure block (7010) fixedly connected to its upper surface. The pressure block (7010) has a groove for sliding an annular pressure rod (709). One section of the annular pressure rod (709) is wavy.

6. The permanent magnet synchronous motor core welding device according to claim 1, characterized in that: The auxiliary mechanism (5) includes a fixing plate (501) fixedly connected to the outer surface of the laser welding gun body (4). A Y-shaped push rod (502) is fixedly connected to the front end of the fixing plate (501). Two abutting blocks (503) are fixedly connected to the front end of the Y-shaped push rod (502) and abut against the inner wall of the iron core welding groove on both sides. The outer surface of the two abutting blocks (503) is provided with several protrusions.

7. The permanent magnet synchronous motor core welding device according to claim 6, characterized in that: The rear ends of the fixed plate (501) are connected to two pressure rollers by two connecting rods (504), and a gear assembly is installed on the outer side of one of the connecting rods (504).

8. The permanent magnet synchronous motor core welding device according to claim 7, characterized in that: The pressure roller includes an inner hub (505) and an outer silicone sleeve (506). The two inner hubs (505) are fixedly connected by a rotating shaft (507). The two ends of the rotating shaft (507) are rotatably connected to two connecting rods (504) respectively through two bearings. The gear assembly includes a large gear (508) fixedly inserted into one end of a rotating shaft (507), a small gear (509) meshing with one side of the large gear (508), and the output shaft of a drive motor (5010) fixedly inserted into the inner wall of the small gear (509).

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