New energy light truck body-in-white welding transfer system and method

Abstract

The present application provides a new energy light truck body-in-white welding transfer system and method, comprising a ground magnetic stripe navigation system, a roller type transfer AGV, a bearing type AGV, a plurality of welding stations, an online lifting and transverse roller bed, a main welding line roller bed, an offline lifting roller bed and a skid changing station; the ground magnetic stripe navigation system is laid on a single ground base layer and comprises a plurality of double-circuit independent magnetic stripe paths, which respectively constitute a roller type AGV path, a bearing type AGV path and a backflow path; the roller type transfer AGV is used for transferring skids and bodies in the main welding line, the bearing type AGV is used for transferring body-in-whites in the adjustment line, and the skid changing station realizes the body switching between the two AGVs. The present application does not need deep excavation and high-altitude net rack, has short construction period and low cost, supports multi-model high-precision mixed line production and rapid capacity expansion, and realizes full-process unmanned automatic closed-loop circulation.

Description

Technical Field

[0001] This invention relates to a welding and transfer system and method for the body-in-white of a new energy light truck, and pertains to the field of vehicle production technology. Background Technology

[0002] Currently, traditional light truck body-in-white welding production lines suffer from the following technical challenges: I. Rigidity of Conveying and Layout Existing welding lines generally use plate chain or reciprocating rod conveyor lines. Once the conveying path and workstation layout are built, they are fixed and locked, making it impossible to be compatible with mixed production of multiple vehicle models, and it is also difficult to make adjustments later according to production needs.

[0003] II. High requirements for civil engineering and supporting facilities Constructing such a production line requires extensive earthwork excavation, ground foundation treatment, and pre-embedding of mechanical guide rails. It also requires the construction of a high-altitude two-story steel structure grid and a large-scale elevator unit, resulting in a long construction period and high project costs.

[0004] 3. Poor expandability and flexibility The rigid layout of the welding line lacks space for future expansion, resulting in a fixed production cycle. When capacity is increased or a new model is introduced, the entire line will need to be extensively modified or even rebuilt, leading to significant losses from downtime and substantial waste of investment.

[0005] IV. Defects in Existing AGV Applications Conventional AGVs for transport are mostly flatbed driven load-bearing structures with no power on the platform, making them unable to autonomously complete the active docking and transfer of skids. Their movement methods mostly involve stationary rotation or sharp right-angle turns, which are prone to jamming, equipment interference and collisions during operation, resulting in poor automation continuity and stability.

[0006] V. Low production line utilization rate Traditional welding line fixtures are mostly fixed structures, which cannot adaptively adjust the width and are difficult to accommodate the co-production of various wide cabs, resulting in low production line utilization and redundant investment due to the construction of separate lines for multiple models.

[0007] VI. Lack of precision control The production line lacks standardized control over the docking accuracy between workstations, and the connection height difference between different equipment is large, which can easily cause collisions with the vehicle body and deviations in welding accuracy.

[0008] 7. Poor compatibility with new energy vehicles and export models Traditional welding lines use fixed tooling structures, making it impossible to quickly switch between left-hand drive and right-hand drive cab production lines. Furthermore, they lack compatibility with the rapid iteration of new energy vehicle models and the resulting changes in cab width, severely restricting the market responsiveness of new energy vehicle manufacturers.

[0009] Prior art 1 (publication number CN117884815A) discloses an AGV operation method for welding. In this scheme, the AGV integrates welding functions but does not realize long-distance skid transfer between welding stations.

[0010] Prior art 2 (publication number CN118722397B) discloses a novel heavy-duty lurking lifting AGV for automotive welding production lines. This solution uses AGVs in welding production lines, but adopts a lifting-type load-bearing structure, which cannot actively drive the transfer skids, and does not involve dual AGV zone collaboration.

[0011] In addition, the current welding production line is limited to partial transfer between floor beams, floor panels and final assembly workstations, and fails to achieve a closed-loop flow of the main welding line and adjustment line and flexible expansion at the production line level. Summary of the Invention

[0012] To address the problems arising from the aforementioned background technology, this invention provides a welding and transfer system and method for the body-in-white of a new energy light truck. The specific technical solution is as follows: A new energy light truck body welding and transfer system includes: The ground magnetic strip navigation system includes multiple dual-loop independent magnetic strip paths laid on a single ground base layer. The multiple dual-loop independent magnetic strip paths include a roller-type AGV path arranged along the main welding line, a load-bearing AGV path arranged along the adjustment line, and a return path connecting the downstream end and the upstream end of the main welding line. At least one roller-type AGV is provided on the path of the roller-type AGV. The bottom of the roller-type AGV is provided with an omnidirectional moving wheel set, and the top of the roller-type AGV is provided with a self-powered roller unit, an electric blocking and limiting mechanism, and an infrared reflector sensor. At least one load-bearing AGV is installed on the path of the load-bearing AGV; Multiple welding stations are arranged sequentially along the main welding line, and the first welding station includes an upper lifting and transverse roller bed and a servo width adaptive fixture. The upper lifting and transverse roller bed is connected to the roller unit on the top of the roller transfer AGV, and the servo width adaptive fixture is located on both sides of the upper lifting and transverse roller bed. The upper lifting and transverse roller bed is located at the upstream end of the main welding line and is connected to the roller unit on the top of the roller transfer AGV; Main welding line roller bed, set along the main welding line, is used to convey skids; The lower lifting roller bed is located at the downstream end of the main welding line; The skid-changing station, located at the beginning of the adjustment line, is used to lift and separate the white body from the skid, realizing the body transfer from the roller-type transfer AGV to the load-bearing AGV.

[0013] Optionally, the servo width adaptive fixture includes a servo motor, a lead screw, a left positioning unit, and a right positioning unit. The servo motor drives the lead screw to synchronously center and adjust the left and right positioning units.

[0014] Optionally, the docking height error between the upper lifting transverse roller bed and the roller-type transfer AGV is ≤2mm; The adaptive lifting stroke of the lowering roller bed is 100-150mm.

[0015] Optionally, the roller-type transfer AGV and the load-bearing AGV operate in zones based on the dual-loop independent magnetic strip path.

[0016] Optionally, the magnetic strips in the dual-loop independent magnetic strip path are flexible magnetic strips, which are fixed to the ground base layer by an adhesive layer; The magnetic strip trajectory at the turning point of the roller AGV path is set as an arc R angle. The turning radius of the arc R angle is greater than the minimum turning radius required for the roller AGV to make a right-angle turn, and the magnetic strip trajectory at the turning point is a continuous smooth curve.

[0017] Optionally, it also includes a charging station, which is located beside the dual-loop independent magnetic strip path, and the charging station has a charging interface that connects to the roller-type transfer AGV and the load-bearing AGV.

[0018] Optionally, it also includes a vehicle body buffer station, which is located between the adjustment line and the painting line, and the vehicle body buffer station is provided with a disengagement station for separating the load-bearing AGV from the tractor.

[0019] Optionally, the load-bearing AGV path includes a parallel buffer path and a straight path, as well as a path selection mechanism located on the adjustment line, the path selection mechanism being used to switch between the buffer path and the straight path.

[0020] Optionally, the main welding line is reserved with at least two additional welding stations for capacity expansion, and the number of the roller transfer AGV and the load-bearing AGV matches the number of additional welding stations.

[0021] A method for welding and transferring the body-in-white of a new energy light truck, applied to any of the systems described above, includes the following steps: When the skid is loaded onto the line, the roller transfer AGV transports the empty skid to the upper lifting and transverse roller bed; the upper lifting and transverse roller bed adjusts its height for the first time until it is flush with the roller surface of the roller transfer AGV to receive the empty skid; the upper lifting and transverse roller bed moves to the side of the main welding line roller bed, and adjusts its height for the second time until it is flush with the main welding line roller bed to transfer the empty skid to the main welding line roller bed. Adaptive welding: The servo-width adaptive fixture 12 adjusts to the corresponding width and clamps the workpiece; the welding robot then performs the welding. Offline transfer: The offline lifting roller bed is first adjusted to be flush with the main welding line roller bed to receive the skid carrying the white body; the offline lifting roller bed is second adjusted to be flush with the roller surface of the roller transfer AGV to transfer the skid carrying the white body to the roller transfer AGV. The dual AGVs work together to transfer the car body from both sides of the skid at the skid-changing station, separating the car body from the skid. The roller-type transfer AGV carries the separated skid back to the upstream end of the main welding line. The load-bearing AGV moves to a position below the skid-changing station. The skid-changing station transfers the car body onto the load-bearing AGV. The load-bearing AGV enters the adjustment line along the load-bearing AGV path. After unloading the empty skid, the roller-type transfer AGV returns to the upstream end of the main welding line via a pre-set arc-shaped R-angle magnetic strip track on the ground. Adaptive welding: The servo-width adaptive fixture adjusts to the corresponding width and clamps the workpiece; the welding robot then performs the welding. Automatic power replenishment and standby: During idle periods of production, roller-type transfer AGVs and load-bearing AGVs will run to the charging station, automatically replenish power, and enter standby sleep mode.

[0022] The beneficial effects of this invention compared to the prior art are as follows: While retaining the core process requirements, this invention eliminates the need for deep civil engineering excavation, high-altitude steel structure grids, and large lifting mechanisms. Compared with traditional rigid welding lines, it can significantly reduce civil engineering and equipment investment costs, shorten the production line construction cycle, and reduce losses from subsequent modification and shutdown. By adopting magnetic strip navigation and modular layout, when production capacity is increased or new models are introduced, it is only necessary to re-lay magnetic strips, add AGVs and robots, and only require a short-term commissioning and shutdown to complete the task, thus achieving rapid expansion with low cost and low downtime. The roller-type transfer AGV actively combines with the lifting roller bed to convey the skid, saving the heavy manual labor of 4 people; the round arc R-angle magnetic strip trajectory turning path eliminates the risk of jamming and interference caused by hard turning on the spot, resulting in smooth operation and low equipment wear; The docking height error is controlled within 2mm. The adaptive lifting stroke of the lower line lifting roller bed is 100-150mm to achieve flexible compensation. Combined with the servo width adaptive tooling, it can stably achieve high-precision mixed-line production of various wide cabs. Roller-type transfer AGVs and load-bearing AGVs are professionally divided, operate in separate zones, and do not interfere with each other. Seamless vehicle body handover is completed through lifting roller beds and skid changing stations, realizing a fully unmanned automatic closed loop from empty skid loading to white body conveying and painting. This innovative roller-type AGV features a "top powered roller, electric blocking and limiting mechanism, and bottom omnidirectional wheel set," enabling it to autonomously drive a skid and navigate curves using a circular arc R-angle magnetic strip trajectory.

[0023] A single production line can be compatible with the co-production of various wide-width light truck cabs, supports seamless switching between left-hand drive and right-hand drive models, eliminates the need for separate line construction and fixture replacement, perfectly adapts to the rapid iteration of new energy vehicle models and the demands of the export market, and significantly improves the utilization rate of the production line. Attached Figure Description

[0024] Figure 1 This is an overall framework diagram of the present invention; Figure 2 This is a schematic diagram of the docking between the lifting and transverse roller bed and the roller-type transfer AGV in this invention; Figure 3 This is a schematic diagram of the turning radius (R-angle) of the roller-type AGV path in this invention; Figure 4 This is a schematic diagram of the servo width adaptive fixture in this invention; Figure 5 This is a flowchart of the method in this invention.

[0025] Attached Figure Captions 1. Main welding line; 2. Roller AGV path; 3. Adjustment line; 4. Load-bearing AGV path; 5. Return path; 6. Roller transfer AGV; 7. Load-bearing AGV; 8. Upper line lifting and traversing roller bed; 9. Lower line lifting roller bed; 10. Skid changing station; 11. Skid; 12. Servo width adaptive tooling; 121. Servo motor; 122. Lead screw; 123. Left positioning unit; 124. Right positioning unit; 13. Charging station; 14. Body buffer station; 15. Painting line entrance; 16. Path selection mechanism; 17. Additional welding station; 18. Main welding line roller bed. Detailed Implementation

[0026] 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.

[0027] Example 1 like Figure 1 As shown, a new energy light truck body welding and transfer system includes: The ground magnetic strip navigation system includes multiple dual-loop independent magnetic strip paths laid on a single ground base. The multiple dual-loop independent magnetic strip paths include a roller-type AGV path 2 arranged along the main welding line 1, a load-bearing AGV path 4 arranged along the adjustment line 3, and a return path 5 connecting the downstream end and the upstream end of the main welding line 1. At least one roller-type transfer AGV6 is installed on roller-type AGV path 2. The bottom of the roller-type transfer AGV6 is equipped with an omnidirectional moving wheel set, and the top of the roller-type transfer AGV6 is equipped with a self-powered roller unit, an electric blocking limit mechanism, and an infrared reflector sensor. At least one load-bearing AGV 7 is installed on load-bearing AGV path 4; Multiple welding stations are set up sequentially along the main welding line 1. The first welding station includes an upper lifting and transverse roller bed 8 and a servo width adaptive fixture 12. The upper lifting and transverse roller bed 8 is connected to the roller unit on the top of the roller transfer AGV6. The servo width adaptive fixture 12 is located on both sides of the upper lifting and transverse roller bed 8. The roller-type transfer AGV6 carries an empty skid 11 and travels smoothly along the roller-type AGV path 2 to the upper lifting and transverse roller bed 8.

[0028] The upper lifting and transverse roller bed 8 is located at the upstream end of the main welding line 1 and is connected to the roller unit on the top of the roller transfer AGV 6; The main welding line roller bed 18 is arranged along the main welding line 1 and is used to convey the skid 11; The lower lifting roller bed 9 is located at the downstream end of the main welding line 1; The skid-changing station 10, located at the beginning of the adjustment line 3, is used to lift and separate the white body from the skid 11, realizing the body transfer from the roller-type transfer AGV6 to the load-bearing AGV7.

[0029] like Figure 4 As shown, the servo width adaptive fixture 12 includes a servo motor 121, a lead screw 122, a left positioning unit 123, and a right positioning unit 124. The servo motor 121 drives the lead screw 122 to drive the left positioning unit 123 and the right positioning unit 124 to adjust synchronously. The adjustable width range is for narrow-body, standard-body, and wide-body light truck cabs.

[0030] The docking height error between the upper lifting transverse roller bed 8 and the roller-type transfer AGV6 is ≤2mm; The adaptive lifting stroke of the lower lifting roller bed 9 is 100-150mm.

[0031] The roller-type transfer AGV6 and the load-bearing AGV7 operate in zones based on dual-loop independent magnetic strip paths.

[0032] The magnetic strips in the dual-circuit independent magnetic strip path are flexible magnetic strips, which are fixed to the ground base layer by an adhesive layer; The magnetic strip trajectory at the turning point of the roller AGV path 2 is set as an arc R angle. The turning radius of the arc R angle is greater than the minimum turning radius required for the roller AGV 6 to make a right-angle turn, and the magnetic strip trajectory at the turning point is a continuous smooth curve.

[0033] It also includes a charging station 13, which is located beside the dual-circuit independent magnetic strip path. The charging station 13 has a charging interface that connects to the roller-type transfer AGV6 and the load-bearing AGV7.

[0034] It also includes a body buffer station 14, which is located between the adjustment line 3 and the painting line 15. The body buffer station 14 is equipped with a disengagement station for separating the load-bearing AGV7 from the tractor.

[0035] The load-bearing AGV path 4 includes a parallel buffer path and a straight path, as well as a path selection mechanism 16 located on the adjustment line 3. The path selection mechanism 16 is used to switch between the buffer path and the straight path.

[0036] The main welding line 1 is reserved with at least two additional welding stations 17 for capacity expansion, and the number of roller transfer AGV6 and load-bearing AGV7 matches the number of additional welding stations 17.

[0037] Example 2 like Figure 5 As shown, a method for welding and transferring the body-in-white of a new energy light truck, applied to any of the systems described above, includes the following steps: When the skid 11 is put on the line, the roller transfer AGV6 transports the empty skid 11 to the upper lifting and transverse roller bed 8; the upper lifting and transverse roller bed 8 adjusts its height for the first time to be flush with the roller surface of the roller transfer AGV6, and receives the empty skid 11; the upper lifting and transverse roller bed 8 moves to the side of the main welding line roller bed 18, and adjusts its height for the second time to be flush with the main welding line roller bed 18, and transfers the empty skid 11 to the main welding line roller bed 18; Adaptive welding: The servo width adaptive fixture 12 is adjusted to the corresponding width and clamps the workpiece; the welding robot performs online welding operations to complete the welding of the white body floor assembly, side panels and roof. Offline transfer: The offline lifting roller bed 9 is first adjusted to be flush with the main welding line roller bed 18 to receive the skid 11 carrying the white body; the offline lifting roller bed 9 is second adjusted to be flush with the roller surface of the roller transfer AGV6 to transfer the skid 11 carrying the white body to the roller transfer AGV6. The two AGVs work together to transfer the car body. The skid-changing station 10 lifts the car body from both sides of the skid 11, separating the car body from the skid 11. The roller-type transfer AGV 6 carries the separated skid 11 back to the upstream end of the main welding line 1. The load-bearing AGV 7 runs to the position below the skid-changing station 10. The skid-changing station 10 transfers the car body to the load-bearing AGV 7. The load-bearing AGV 7 enters the adjustment line 3 along the load-bearing AGV path 4. After unloading the empty skid 11, the roller-type transfer AGV6 turns 90 degrees along the preset arc R-angle magnetic strip track on the ground and returns to the upstream end of the main welding line 1 via the return path. Automatic power replenishment and standby: During idle periods of production, the roller conveyor AGV6 and the load-bearing AGV7 will run to the charging station 13, automatically replenish power, and enter standby sleep mode.

[0038] Example 3 The present invention will be further described in detail below with reference to specific embodiments, but the implementation of the present invention is not limited thereto.

[0039] Taking the construction of a welding line in a new energy light truck factory with a designed cycle time of 14 JPH, which can be upgraded to 18 JPH, as an example. After simple leveling, the existing workshop floor is laid with a dual-loop independent magnetic strip path. Main welding line 1 has 11 welding stations, plus 2 reserved upgrade stations and 2 reserved transition stations, with a station spacing of 4.5 meters. (The remaining text appears to be unrelated and possibly machine-generated.) Figure 3 As shown, the turning radius of the circular arc R-angle magnetic strip track is set to 1200mm. This value is only an example; in actual applications, it can be adapted and adjusted according to the AGV body size, running speed, and workshop space conditions, as long as it meets the requirements of continuous and smooth turning and eliminates the risk of jamming and interference caused by hard right-angle turns. Four roller-type transfer AGV6 units and eighteen load-bearing AGV7 units are configured.

[0040] The following is an example of a fully automated closed-loop production process, taking the production of a standard-width pure electric light truck cab as an example: I. Precise Deployment of Air Skids The roller-type transfer AGV6 carries an empty skid 11 and travels smoothly along the roller-type AGV path 2 to the upper lifting and transverse roller bed 8, where it is positioned by an infrared reflector sensor.

[0041] like Figure 2 As shown, the following height references are defined: H1 is the height of the roller surface of the roller transfer AGV6, H2 is the height of the bearing surface of the upper lifting and transverse roller bed 8, and H3 is the height of the bearing surface of the main welding line roller bed 18.

[0042] Once the limit sensor detects that the roller conveyor AGV6 has reached its designated position, the roller conveyor AGV6 stops moving. The upper lifting and transverse roller bed 8 adjusts its height until H2 and H1 are aligned, with the height difference controlled within 2mm. After the grating sensor confirms the position, it releases the electric blocking limit mechanism of the roller conveyor AGV6, and the self-driven roller unit at the top of the roller conveyor AGV6 rotates actively, transporting the empty skid 11 to the upper lifting and transverse roller bed 8.

[0043] The upper lifting and traversing roller bed 8 moves laterally to the side of the main welding line roller bed 18, and the height is adjusted again until H2 and H3 are aligned, with the height difference controlled within 2mm. After the sensor confirms the position, the rollers of the upper lifting and traversing roller bed 8 are started to smoothly transport the empty skid 11 to the main welding line roller bed 18.

[0044] Through the aforementioned relay-type height adjustment and active transmission, the air skid 11 is put into operation without any drop, and is then transported by the main welding line roller bed 18 to the first welding station for positioning, thus completing the preparation for going online.

[0045] II. Adaptive Welding for Multiple Vehicle Models The central scheduling system matches vehicle model parameters based on production orders, including narrow-body, standard-body, and wide-body series; power type: pure electric or hybrid; steering: left-hand drive or right-hand drive, driving the servo width adaptive tooling 12 to automatically adjust the positioning spacing. The servo motor 121 drives the lead screw 122 to synchronously center and adjust the left positioning unit 123 and right positioning unit 124 to the corresponding width. After debugging, the welding robot operates fully automatically, completing the welding of the body-in-white floor assembly. The gripping robot picks up the floor assembly and places it on the skid 11 of the main welding line roller bed 18, which then transports it to the next welding station for welding operations on the side panels, roof, etc., taking approximately 4 minutes per unit. The reserved additional welding station 17 is in standby mode, reserving the hardware foundation for future capacity expansion.

[0046] III. Bodywork with skid-mounted off-line connection The completed body-in-white, along with its skid 11, flows along the main welding line roller bed 18 to the downstream lifting roller bed 9 at the downstream end of the main welding line 1. The lifting roller bed 9 is first adjusted to be flush with the main welding line roller bed 18, with a height error of no more than 2mm, to receive the skid 11 carrying the body-in-white. The lifting roller bed 9 is then adjusted a second time to be flush with the roller surface of the roller-type transfer AGV6, with a height error of no more than 2mm, precisely docking with the waiting roller-type transfer AGV6, smoothly transferring the skid 11 carrying the body-in-white to the roller-type transfer AGV6, achieving a drop-free and collision-free unloading process.

[0047] IV. Dual AGV Unmanned Automated Skid Changing and Transfer Roller-type transfer AGV 6 carries the skid 11 carrying the car body and moves along roller-type AGV path 2 at a speed of 0.3 meters per second to the skid-changing station 10 at the beginning of adjustment line 3. The load-bearing AGV 7 is in position and ready. After interlock verification, the skid-changing station 10 lifts the car body from both sides of the skid 11, separating it from the skid 11. Roller-type transfer AGV 6 carries the separated empty skid 11 back to the upstream end of main welding line 1, and the load-bearing AGV 7 carries the car body along the load-bearing AGV path 4 into adjustment line 3, completing the skid-changing transfer process automatically throughout.

[0048] V. Circular Arc Flow Circulation After the vehicle body transfer is completed, the roller-type transfer AGV6, carrying the empty skid 11, smoothly completes a 90-degree turn along the preset arc-shaped magnetic strip track on the ground. The turning radius is not less than 1000mm, without any pauses, sharp right-angle turns, or equipment interference. After the turn, it travels straight back to the upstream end of the main welding line 1 along the return path 5, entering the next round of production closed-loop cycle.

[0049] VI. Adjusting the production line to be flexible After receiving the body-in-white, the load-bearing AGV7 flows along the load-bearing AGV path 4 to complete subsequent welding, finishing, and precision verification processes. The production process supports flexible switching between two modes: the path selection mechanism 16 switches between a buffer path and a direct path, allowing the body to be transported to the body buffer station 14 for preparation, or directly to the painting line entrance 15, achieving seamless connection between welding and painting processes.

[0050] VII. Automatic power replenishment standby for equipment During production downtime, the roller-type transfer AGV6 and the load-bearing AGV7, which have completed their cyclical operations, automatically drive into the charging station 13, automatically recharge, and enter standby sleep mode. The entire process is unmanned, ensuring continuous production of the production line 24 hours a day and adapting to the needs of mass production.

[0051] Example 4 The logic behind expanding production line capacity is to increase it from 14 JPH to 18 JPH. This production line is natively expandable. The main welding line 1 has at least two additional welding stations 17 reserved for capacity expansion, with ample space for equipment installation and control interfaces, requiring no modification to civil engineering, no alteration to the main line layout, and no adjustment to the magnetic strip main path.

[0052] The initial production cycle is 14 JPH, meeting basic mass production needs. When market capacity increases later, simply adding welding robots to the additional welding station 17, optimizing the central scheduling program, and fine-tuning the AGV operating cycle can smoothly increase the overall production line capacity to 18 JPH. Simultaneously, leveraging the modular flexibility of AGVs, roller-type transfer AGVs 6 and load-bearing AGVs 7 can be flexibly added according to capacity requirements, ensuring the number of AGVs matches the number of additional welding stations 17, optimizing the transfer cycle cycle, and matching the production efficiency of the newly added stations.

[0053] The entire process involves zero civil engineering renovation costs and zero production downtime. It only requires two days of joint commissioning on weekends, with a total renovation cycle of about three days and renovation costs of about 15% of those for building a new traditional line, thus achieving a smooth upgrade in production capacity.

[0054] Example 5 In actual operation, the collaborative operation of two AGVs follows the following collaborative procedures: I. Zoning Operation Rules The roller-type AGV6's dedicated main welding line area 1 is solely responsible for empty skid loading, skid-mounted transport, and empty skid return circulation; the load-bearing AGV7's dedicated adjustment line area 3 is solely responsible for body-in-white repair transport, buffering, and painting pass-through. Both types of equipment operate on a dual-circuit independent magnetic strip path, with no overlap in their work areas.

[0055] II. Path Interlocking Rules The two AGVs are equipped with independent magnetic strip navigation paths and independent scheduling logic, with physical isolation and program interlocking to prevent cross-operation interference and collision / stuttering issues.

[0056] III. Transfer and Collaboration Rules The transfer station, or skid-changing station 10, is equipped with a dedicated waiting area and verification procedure. After the roller-type transfer AGV6 completes its arrival verification, skid-changing station 10 activates, allowing the load-bearing AGV7 to dock and begin operations. The transfer sequence is precise and controllable, ensuring continuous closed-loop production.

[0057] IV. Scheduling and Coordination Rules The central intelligent dispatch system uniformly manages the operating speed, stopping position, operation sequence, and charging logic of the two types of AGVs, realizing the coordinated linkage of all equipment and maximizing the improvement of production cycle and operational stability.

Claims

1. A new energy light truck body welding and transfer system, characterized in that, include: The ground magnetic strip navigation system includes multiple dual-loop independent magnetic strip paths laid on a single ground base layer. The multiple dual-loop independent magnetic strip paths include a roller AGV path (2) arranged along the main welding line (1), a load-bearing AGV path (4) arranged along the adjustment line (3), and a return path (5) connecting the downstream end and the upstream end of the main welding line (1). At least one roller-type transfer AGV (6) is provided on the roller-type AGV path (2). The bottom of the roller-type transfer AGV (6) is provided with an omnidirectional moving wheel group, and the top of the roller-type transfer AGV (6) is provided with a self-powered roller unit, an electric blocking limit mechanism and an infrared reflector sensor. At least one load-bearing AGV (7) is located on the load-bearing AGV path (4); Multiple welding stations are set up sequentially along the main welding line (1), and the first welding station includes an upper lifting and transverse roller bed (8) and a servo width adaptive fixture (12). The upper lifting and transverse roller bed (8) is connected to the roller unit at the top of the roller transfer AGV (6), and the servo width adaptive fixture (12) is located on both sides of the upper lifting and transverse roller bed (8). The upper lifting transverse roller bed (8) is located at the upstream end of the main welding line (1) and is connected to the roller unit at the top of the roller transfer AGV (6); The main welding line roller bed (18) is set along the main welding line (1) and is used to transport the skid (11). The lower lifting roller bed (9) is located at the downstream end of the main welding line (1); The skid-changing station (10) is located at the beginning of the adjustment line (3) and is used to lift and separate the white body from the skid (11) to realize the body transfer from the roller transfer AGV (6) to the load-bearing AGV (7).

2. The new energy light truck body-in-white welding and transfer system according to claim 1, characterized in that, The servo width adaptive fixture (12) includes a servo motor (121), a lead screw (122), a left positioning unit (123), and a right positioning unit (124). The servo motor (121) drives the lead screw (122) to drive the left positioning unit (123) and the right positioning unit (124) to adjust synchronously.

3. The new energy light truck body-in-white welding and transfer system according to claim 1, characterized in that, The docking height error between the upper lifting transverse roller bed (8) and the roller transfer AGV (6) is ≤2mm; The adaptive lifting stroke of the lower lifting roller bed (9) is 100-150mm.

4. The new energy light truck body-in-white welding and transfer system according to claim 1, characterized in that, The roller-type transfer AGV (6) and the load-bearing AGV (7) operate in partitioned mode based on the dual-loop independent magnetic strip path.

5. The new energy light truck body-in-white welding and transfer system according to claim 1, characterized in that, The magnetic strips in the dual-circuit independent magnetic strip path are flexible magnetic strips, which are fixed to the ground base layer by an adhesive layer; The magnetic strip trajectory at the turning point of the roller AGV path (2) is set as an arc R angle. The turning radius of the arc R angle is greater than the minimum turning radius required for the roller AGV (6) to make a right-angle turn, and the magnetic strip trajectory at the turning point is a continuous smooth curve.

6. The new energy light truck body-in-white welding and transfer system according to claim 1, characterized in that, It also includes a charging station (13), which is located beside the dual-loop independent magnetic strip path. The charging station (13) has a charging interface that is connected to the roller-type transfer AGV (6) and the load-bearing AGV (7).

7. The new energy light truck body-in-white welding and transfer system according to claim 1, characterized in that, It also includes a vehicle body buffer station (14), which is located between the adjustment line (3) and the painting line opening (15). The vehicle body buffer station (14) is provided with a disengagement station for separating the load-bearing AGV (7) from the tractor.

8. The new energy light truck body-in-white welding and transfer system according to claim 4, characterized in that, The load-bearing AGV path (4) includes a parallel buffer path and a straight path, and a path selection mechanism (16) located on the adjustment line (3). The path selection mechanism (16) is used to switch between the buffer path and the straight path.

9. The new energy light truck body-in-white welding and transfer system according to claim 4, characterized in that, The main welding line (1) is reserved with at least two additional welding stations (17) for capacity expansion, and the number of the roller transfer AGV (6) and the load-bearing AGV (7) matches the number of the additional welding stations (17).

10. A method for welding and transferring the body-in-white of a new energy light truck, applied to the system described in any one of claims 1 to 9, characterized in that, Includes the following steps: When the sled (11) is put on the line, the roller transfer AGV (6) transports the empty sled (11) to the upper lifting and transverse roller bed (8); the upper lifting and transverse roller bed (8) adjusts its height for the first time to be flush with the roller surface of the roller transfer AGV (6) and receives the empty sled (11); the upper lifting and transverse roller bed (8) moves to the side of the main welding line roller bed (18) and adjusts its height for the second time to be flush with the main welding line roller bed (18) and transfers the empty sled (11) to the main welding line roller bed (18). Adaptive welding: The servo width adaptive fixture (12) is adjusted to the corresponding width and clamps the workpiece; the welding robot performs welding. Offline transfer: The offline lifting roller bed (9) is first adjusted to be flush with the main welding line roller bed (18) to receive the skid (11) carrying the white body; the offline lifting roller bed (9) is second adjusted to be flush with the roller surface of the roller transfer AGV (6) to transfer the skid (11) carrying the white body to the roller transfer AGV (6). The two AGVs work together to transfer the car body. The skid-changing station (10) lifts the car body from both sides of the skid (11) to separate the car body from the skid (11). The roller transfer AGV (6) carries the separated skid (11) back to the upstream end of the main welding line (1). The load-bearing AGV (7) runs to the position below the skid-changing station (10). The skid-changing station (10) transfers the car body to the load-bearing AGV (7). The load-bearing AGV (7) enters the adjustment line (3) along the load-bearing AGV path (4). After the roller-type transfer AGV (6) unloads the empty skid (11) and turns 90 degrees along the preset arc R-angle magnetic strip track on the ground, it returns to the upstream end of the main welding line (1) via the return path. Automatic power replenishment and standby: During production downtime, the roller-type transfer AGV (6) and the load-bearing AGV (7) run to the charging station (13), automatically replenish power and enter standby hibernation state.

Images