Logistics vehicle main rib welding positioning device

Abstract

The invention relates to the field of welding and positioning of logistics vehicle frames, in particular to a welding and positioning device for main ribs of a logistics vehicle. Comprising an outer expansion plate in sliding connection with the core table, an inner folding plate is arranged on one side of the outer expansion plate in a sliding mode, and the end portion of a main reinforcement curved pipe can be positioned from the two sides of the outer expansion plate; a sliding table is arranged at one end of the working table in a sliding mode, gas sources loaded with helium are arranged at the lower ends of the working table and the sliding table, clamping mechanisms are arranged at the upper ends of the working table and the sliding table, the clamping mechanisms comprise gas pipes communicated with the gas sources, the ends of the curved pipes are inserted outside the gas pipes, and the gas sources can introduce helium into the curved pipes through the gas pipes. The small holes in the side wall of the curved pipe can release redundant helium to create an inert welding space. According to the device, through double-effect utilization of pipe orifice clamping and helium, the problem that an existing device cannot be matched with positioning of irregular curved main rib pipe fittings and cooperative control of welding quality is solved.

Description

Technical Field

[0001] This invention relates to the field of welding and positioning of logistics vehicle frames, specifically to a welding and positioning device for the main ribs of a logistics vehicle. Background Technology

[0002] With the rapid development of the urban logistics industry, the requirements for heavy-duty load-bearing capacity, lightweight design, and adaptability to complex working conditions of logistics vehicles are constantly being upgraded. As the core load-bearing component of the entire logistics vehicle, the main frame ribs directly determine the vehicle's service safety and lifespan through their structural strength, forming precision, and welding quality. To balance lightweight design with high-strength load-bearing requirements, the main frame ribs of mainstream logistics vehicles generally adopt a structure of multiple non-standard tubular components welded together. Due to the compact layout of the logistics vehicle chassis and the limitations of adapting to multiple component assembly interfaces, the tubular components used in these main frame ribs are mostly irregular spatial curved structures, differing from conventional straight cylindrical or constant-curvature arc-shaped tubular components. Their spatial trajectory is complex, with numerous bending points and thin walls, placing extremely high industry requirements on the positioning and clamping accuracy and welding quality control during the welding process.

[0003] Existing positioning equipment for welding the main ribs of logistics vehicles is mostly a single-point external clamping structure designed for regular tubular components. This cannot adapt to the spatial trajectory of non-standard, irregular curved tubular components, making it difficult to achieve precise positioning and rigid constraint along the entire path of the component. During welding, problems such as component movement, misalignment of butt welds, excessive coaxiality of multiple component combinations, and overall spatial distortion are easily encountered, failing to meet the dimensional and positional tolerances of the main ribs and the assembly precision requirements of the entire vehicle. For welding conventional straight cylindrical and constant-curvature arc-shaped tubular components, the industry commonly uses solid positioning inserts that perfectly match the internal trajectory of the component. These inserts are inserted from the end of the component to achieve internal centering and positioning, effectively avoiding the problems of pipe wall extrusion deformation and excessive coaxiality caused by external clamping positioning. However, this method can only adapt to regular tubular components with continuous internal trajectories and constant curvature.

[0004] The non-standard, irregular curved tubular components used in the main ribs of logistics vehicles have multiple segments of varying curvature bends and discontinuous spatial turns within their cavities, with no constant and uniform trajectory to follow. Solid positioning plugs cannot adapt to the complex and ever-changing spatial cavities. Not only can they not be smoothly inserted into the inner cavity of the tube to achieve full-length fitting support and centering, but forced insertion can also easily scratch the inner wall of the tube, causing irreversible plastic deformation at the bends. This makes mature internal positioning solutions completely unsuitable for such non-standard curved tubular components, and the industry has been unable to solve the problem of internal centering and positioning for such tubes. In addition, existing technologies cannot simultaneously solve the problem of coordinating welding protection and deformation control for the welding of thin-walled curved tubular components. Conventional protection methods not only have uneven protection effects and high operating costs, but are also prone to forming protection dead zones due to the irregular inner cavity of the tubular components, leading to defects such as oxidation of the inner wall of the weld and poor molten pool formation. At the same time, they cannot effectively suppress irregular deformation caused by welding heat input. The positioning and clamping functions of existing tooling are completely disconnected from the welding quality control functions, and cannot achieve coordinated adaptation. Therefore, we need to develop a positioning device for welding the main ribs of logistics vehicles that can be adapted to non-standard irregular curved tubular components to fill the gap in existing technology. Summary of the Invention

[0005] Therefore, it is necessary to provide a welding positioning device for the main reinforcing bars of a logistics vehicle to address the existing technical problems.

[0006] To solve the problems of the prior art, the technical solution adopted by the present invention is as follows:

[0007] A welding positioning device for the main reinforcing bars of a logistics vehicle, comprising:

[0008] A fixed workbench has a core platform that is slidably mounted on its upper end. Symmetrical bidirectional clamping mechanisms for clamping the ends of the main rib curved tubes are arranged on both sides of the core platform. The bidirectional clamping mechanisms include an outward expansion plate that is slidably connected to the core platform, and an inward contraction plate that is slidably mounted on the side of the outward expansion plate away from the core platform. The outward expansion plate and the inward contraction plate respectively position the ends of the main rib curved tubes from both sides.

[0009] A slide table is slidably installed at one end of the workbench. Two gas sources loaded with helium are respectively installed at the lower ends of the workbench and the slide table. Two clamping mechanisms for positioning the irregular pipes of the main rib are symmetrically installed at the upper ends of the workbench and the upper ends of the slide table. The clamping mechanism includes a gas pipe connected to the gas source. The pipe opening of the main rib curved pipe is inserted into the outside of the gas pipe during welding. The gas source continuously supplies helium to the main rib curved pipe through the gas pipe to provide it with pressure to resist deformation.

[0010] Small holes are opened on the side wall of the main rib curved tube, and excess helium gas is released from the small holes to create an inert gas welding space for the welding points.

[0011] Furthermore, two lifting devices are symmetrically arranged in the middle of the workbench, with the output ends of the lifting devices facing upwards and each fixedly connected to a flexible plate.

[0012] Furthermore, an electrically operated pull-out plate is installed below the core platform and is fixedly connected to the upper part of the worktable, with the moving end of the electrically operated pull-out plate being fixedly connected to the core platform.

[0013] Furthermore, the bidirectional clamping mechanism also includes a core frame that is slidably connected to the inner wall of the core platform. The core frame is hollow inside and is equipped with a first cylinder. The fixed end of the first cylinder is fixedly connected to the core platform, and the output end is fixedly connected to the core frame.

[0014] Main sliders are fixedly arranged in an equally spaced array on both sides of the core frame along the long side direction. Secondary sliders are slidably connected in an equally spaced array on both sides of the core platform along the long side direction. The main sliders and secondary sliders correspond one to one and are respectively formed with inclined surfaces on the side that is close to each other. The main sliders and secondary sliders are slidably connected through the inclined surfaces.

[0015] The outer expansion plate is fixedly connected to the corresponding secondary slider on the side closest to the core stage. A first tension spring is provided on the side of two adjacent secondary sliders. One end of the first tension spring is fixedly connected to the outer expansion plate, and the other end is fixedly connected to the core stage.

[0016] Furthermore, a second cylinder is inclinedly installed on the side of the inner retracting plate away from the core stage. The second cylinder is fixedly connected to the worktable via a support, and the output end of the second cylinder is fixedly connected to the inner retracting plate.

[0017] Furthermore, two electric actuators are symmetrically arranged at one end of the worktable near the slide. The fixed end of the electric actuator is fixedly connected to the upper end of the worktable, and the output end is fixedly connected to the upper end of the slide. The two sides of the slide are slidably connected to the worktable through guide rails.

[0018] Furthermore, a rubber sealing ring is coaxially fixed to the root of the trachea, and when the main rib curved pipe is fitted at the root of the trachea, the rubber sealing ring and the pipe opening of the main rib curved pipe are interference-fitted.

[0019] Furthermore, a conical head is coaxially inserted into the end of the trachea, and a one-way valve is coaxially fixed to the conical head.

[0020] Furthermore, the outer wall of the trachea is provided with equal-angled capacity grooves along the circumference, and each capacity groove is slidably provided with a pad, and the side of the pad away from the capacity groove is provided with anti-slip texture.

[0021] Each volumetric trough is arranged with hollow tubes at equal intervals along its long side. The hollow tubes are dynamically sealed to the outer wall of the air tube. The open end of the hollow tube is connected to the inside of the air tube, and the closed end is fixedly connected to the pad.

[0022] A second tension spring is coaxially sleeved on the outside of the hollow tube. One end of the second tension spring is fixed to the volume groove, and the other end is fixed to the pad. When the gas source continuously supplies helium into the tube, the hollow tube moves the pad away from the tube under pressure until the pad tightens the inner wall of the main rib curved tube.

[0023] Furthermore, an electric gripper is coaxially fitted on the outside of the trachea. When the main rib curved tube is inserted into the outside of the trachea, the electric gripper clamps the outer wall of the main rib curved tube.

[0024] The beneficial effects of this invention compared to the prior art are:

[0025] Firstly, this solution effectively solves the core defect of existing technologies that cannot achieve precise internal centering and positioning of irregularly curved main rib pipe fittings. By inserting the air pipe of the clamping mechanism into the pipe opening of the main rib curved pipe, a unified internal hole positioning benchmark is established, avoiding the problems of solid positioning plugs being unable to adapt to the variable curvature bending inner cavity and easily damaging the pipe fittings. At the same time, with the bidirectional clamping mechanism on both sides of the core stage, the outward expansion plate and the inward contraction plate clamp simultaneously in both directions, achieving bidirectional rigid limiting of the end, which can completely restrain the movement of the pipe fittings, weld misalignment, and overall spatial distortion during the welding process. Furthermore, this device can also adapt to non-standard curved pipes of different specifications through the sliding of the core stage and the slide, greatly improving the positioning accuracy and tooling versatility.

[0026] Secondly, this solution achieves synergistic adaptation between welding deformation prevention and welding protection. Helium is continuously introduced into the inner cavity of the curved tube through the gas source and gas pipe to form a stable positive pressure in the inner cavity, providing uniform internal support for the thin-walled tube wall, effectively offsetting welding thermal stress, and suppressing irregular welding deformation of the irregular curved tube. At the same time, excess helium is slowly released through small holes in the side wall of the curved tube, forming a continuous inert protective atmosphere at the welding point, with no blind spots in protection, completely avoiding defects such as weld oxidation and poor molten pool formation, and significantly improving the yield and quality stability of the main rib welding. Attached Figure Description

[0027] Figure 1 This is a three-dimensional structural diagram of an embodiment;

[0028] Figure 2 yes Figure 1 Enlarged view of the structure at point A in the middle;

[0029] Figure 3 This is a three-dimensional structural schematic diagram from another angle of the embodiment;

[0030] Figure 4 yes Figure 3 Enlarged view of the structure at point B in the middle;

[0031] Figure 5 This is a three-dimensional structural diagram of the core frame, the outer expansion plate, and the inner contraction plate in the embodiment;

[0032] Figure 6 yes Figure 5 Enlarged view of the structure at point C;

[0033] Figure 7 This is a three-dimensional structural diagram of the trachea and pad in the embodiment;

[0034] Figure 8 This is a three-dimensional half-sectional view of the trachea in the embodiment;

[0035] Figure 9 yes Figure 8 Enlarged view of the structure at point D.

[0036] The numbers on the map are:

[0037] 1. Workbench; 2. Electric pull-out plate; 3. Core platform; 4. Two-way clamping mechanism; 5. First cylinder; 6. Core frame; 7. Main slider; 8. Secondary slider; 9. Outer expansion plate; 10. First tension spring; 11. Second cylinder; 12. Inner retraction plate; 13. Slide table; 14. Electric push rod; 15. Clamping mechanism; 16. Air pipe; 17. Rubber sealing ring; 18. Conical head; 19. One-way valve; 20. Capacity groove; 21. Hollow tube; 22. Second tension spring; 23. Pad; 24. Anti-slip texture; 25. Electric gripper; 26. Flexible plate; 27. Lifting device; 28. Air source. Detailed Implementation

[0038] To further understand the features, technical means, and specific objectives and functions achieved by the present invention, the present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

[0039] refer to Figures 1 to 9 A welding positioning device for the main reinforcing bars of a logistics vehicle, comprising:

[0040] A fixed workbench 1 is provided, and a core platform 3 is slidably provided on the upper end of the workbench 1. A bidirectional clamping mechanism 4 for clamping the end of the main rib curved tube is symmetrically provided on both sides of the core platform 3. The bidirectional clamping mechanism 4 includes an outer expansion plate 9 slidably connected to the core platform 3. An inner retraction plate 12 is slidably provided on the side of the outer expansion plate 9 away from the core platform 3. The outer expansion plate 9 and the inner retraction plate 12 respectively position the end of the main rib curved tube from both sides.

[0041] A slide table 13 is slidably provided at one end of the workbench 1. Two gas sources 28 loaded with helium are respectively provided at the lower ends of the workbench 1 and the slide table 13. Two clamping mechanisms 15 for positioning the irregular pipes of the main rib are symmetrically provided at the upper ends of the workbench 1 and the upper ends of the slide table 13. The clamping mechanism 15 includes a gas pipe 16 connected to the gas source 28. The pipe opening of the main rib curved pipe is inserted into the outside of the gas pipe 16 during welding. The gas source 28 continuously supplies helium to the main rib curved pipe through the gas pipe 16 to provide it with pressure to resist deformation.

[0042] Small holes are opened on the side wall of the main rib curved tube, and excess helium gas is released from the small holes to create an inert gas welding space for the welding points.

[0043] When this device is in operation, it uses the workbench 1 as the overall mounting base and first completes the precise positioning and clamping of the main rib curved pipe to be welded. Before operation, the operator first adjusts the sliding position of the core platform 3 on the upper end of the workbench 1 according to the spatial length and trajectory of the main rib curved pipe, and simultaneously adjusts the sliding position of the slide table 13 at the end of the workbench 1 to adapt to the overall size and installation point of the curved pipe. Then, the operator inserts the pipe end of the main rib curved pipe into the outside of the air pipe 16 of the clamping mechanism 15 at the upper end of the workbench 1 and the slide table 13, respectively. Using the air pipe 16 as the internal reference, the inner hole of the curved pipe end is centered to eliminate the coaxiality deviation of the connection. Then, the bidirectional clamping mechanism 4 on both sides of the core platform 3 is driven to move. The outer expansion plate 9 and the inner contraction plate 12 slide towards each other along the core platform 3, and simultaneously clamp the curved pipe from both sides, completing the rigid locking of the curved pipe end. This completely restrains the movement and displacement of the pipe during the welding process, laying a stable positioning foundation for subsequent welding operations.

[0044] After positioning and locking are completed, the operator activates the helium gas source 28 at the lower end of the worktable 1 and slide 13. The gas source 28 delivers helium to the gas pipe 16 of the clamping mechanism 15 through a connecting pipeline, and then continuously injects helium into the inner cavity of the main rib curved tube that has been inserted and sealed through the gas pipe 16. The helium continuously fills the inner cavity of the irregular curved tube, forming a stable internal positive pressure, providing uniform radial support force to the tube wall of the thin-walled curved tube, directly offsetting the tube wall shrinkage stress caused by heat input during welding and the warping deformation tendency at the bend, suppressing the irregular welding deformation of the irregular curved tube from the inner cavity of the tube, and solving the industry pain point that conventional processes cannot control the welding deformation of curved tubes.

[0045] During the continuous helium gas injection, the device simultaneously achieves full-area inertial protection of the welding points, completing a closed loop for the entire welding operation. The pre-formed small holes on the sidewall of the main rib curved tube form stable pressure relief channels, allowing excess helium in the inner cavity to be slowly released through these holes. This creates a continuous inert gas protective atmosphere around the welding points of the curved tube, isolating it from oxygen in the air and completely avoiding defects such as weld oxidation and poor weld pool formation. Throughout the welding process, the sliding core stage 3 and slide stage 13 can flexibly adapt to irregular curved tubes of different specifications, simultaneously achieving three core functions: precise positioning and clamping, welding deformation control, and weld inertial protection, thus completing the high-quality welding of the main rib curved tube.

[0046] To provide auxiliary support for the main rib curved pipe during the clamping and positioning process, the following features are specifically designed:

[0047] like Figure 1As shown, two lifting devices 27 are symmetrically arranged in the middle of the workbench 1. The output ends of the lifting devices 27 are set upward and are respectively fixed to flexible plates 26. During operation, according to the diameter and suspension height of the main rib curved pipe, the lifting devices 27 drive the flexible plates 26 to be lifted vertically, so that the arc-shaped support surface completely fits the lower side wall of the main rib curved pipe. This provides uniform flexible support for the suspended section of the curved pipe during welding, avoids the curved pipe from sagging due to its own weight, and buffers the vibration during the welding process, further improving the stability of clamping and positioning.

[0048] To achieve the horizontal displacement of the core stage 3, the following features were specifically designed:

[0049] like Figure 3 As shown, an electrically operated pull-out plate 2 is fixedly connected to the upper end of the worktable 1 below the core platform 3. The moving end of the electrically operated pull-out plate 2 is fixedly connected to the core platform 3. Before operation, according to the axial dimensions of the main rib curved tube and the clamping point requirements, the electrically operated pull-out plate 2 moves and drives the core platform 3 to move back and forth in a precise straight line along the guide slide. After adjusting to the preset clamping position, it automatically locks. It is compatible with main rib curved tubes of different lengths and specifications, eliminating the need for manual disassembly and adjustment, and greatly improving the versatility and adjustment efficiency of the device.

[0050] To provide a detailed explanation of the movement method of the outer expansion plate 9, the following features are also provided:

[0051] like Figure 1 , Figure 2 and Figure 5 As shown, the bidirectional clamping mechanism 4 also includes a core frame 6 that is slidably connected to the inner wall of the core platform 3. The core frame 6 is hollow inside and is equipped with a first cylinder 5. The fixed end of the first cylinder 5 is fixedly connected to the core platform 3, and the output end is fixedly connected to the core frame 6.

[0052] Main sliders 7 are fixedly connected to the two sides of the core frame 6 at equal intervals along the long side. Secondary sliders 8 are slidably connected to the two sides of the core platform 3 at equal intervals along the long side. The main sliders 7 and secondary sliders 8 correspond one to one and are close to each other with inclined surfaces formed on their respective sides. The main sliders 7 and secondary sliders 8 are slidably connected through the inclined surfaces.

[0053] The outer expansion plate 9 is fixedly connected to the corresponding auxiliary slider 8 on the side close to the core stage 3. A first tension spring 10 is provided on the side close to the two adjacent auxiliary sliders 8. One end of the first tension spring 10 is fixedly connected to the outer expansion plate 9, and the other end is fixedly connected to the core stage 3.

[0054] The inclined surfaces of the main slider 7 and the auxiliary slider 8 have the same angle and fit together, forming a wedge transmission pair. During operation, the first cylinder 5 drives the core frame 6 to move the main slider 7 axially, which in turn pushes the auxiliary slider 8 through the inclined surface to move the outer expansion plate 9 away from the core frame 6, thus allowing the outer expansion plate 9 to support the inner wall of the curved tube end from the inside. When the first cylinder 5 resets, the first tension spring 10 pulls the outer expansion plate 9 to automatically return to its original position, completing the unlocking process.

[0055] To provide a detailed explanation of the movement of the inner retractor 12, the following features are also provided:

[0056] like Figure 1 and Figure 2 As shown, a second cylinder 11 is inclinedly arranged on the side of the inner retracting plate 12 away from the core stage 3. The second cylinder 11 is fixedly connected to the worktable 1 through a support, and the output end of the second cylinder 11 is fixedly connected to the inner retracting plate 12.

[0057] During operation, the piston rod of the second cylinder 11 extends, driving the inner retracting plate 12 to move along an inclined trajectory towards the outer expanding plate 9. It then cooperates with the outer expanding plate 9 to simultaneously clamp and position the curved tube from both the inner and outer sides of the end. When the piston rod of the second cylinder 11 retracts, it moves the inner retracting plate 12 away from the outer expanding plate 9, releasing the clamping constraint on the end of the curved tube. The inclined cylinder provides bidirectional clamping force in both the radial and axial directions, preventing axial movement during the welding process and improving clamping stability.

[0058] To achieve stable displacement of the slide 13, the following features are specifically designed:

[0059] like Figure 4 As shown, two electric actuators 14 are symmetrically arranged at one end of the worktable 1 near the slide table 13. The fixed end of the electric actuator 14 is fixedly connected to the upper end of the worktable 1, and the output end is fixedly connected to the upper end of the slide table 13. The two sides of the slide table 13 are slidably connected to the worktable 1 via guide rails. Before operation, according to the overall axial length of the main rib curved pipe, the two electric actuators 14 are driven to extend and retract synchronously, causing the slide table 13 to make precise linear displacement along the linear guide rail. The distance between the slide table 13 and the worktable 1 is adjusted to accommodate main rib curved pipes of different lengths. The synchronous drive of the two electric actuators 14 can ensure the coaxiality of the slide table 13 displacement and avoid the problem of swaying and jamming.

[0060] To ensure a sealed connection between the curved tube opening and the air pipe 16 when the main rib's curved tube opening is inserted into the outside of the air pipe 16, thereby preventing gas leakage between the air pipe 16 and the curved tube opening when the gas source 28 supplies helium to the air pipe 16, the following features are specifically provided:

[0061] like Figure 4 As shown, a rubber sealing ring 17 is coaxially fixed to the root of the trachea 16. When the main rib curved pipe is fitted onto the root of the trachea 16, the rubber sealing ring 17 and the pipe opening of the main rib curved pipe are interference-fitted.

[0062] When the main rib curved tube is inserted into the outside of the air pipe 16, the inner wall of the curved tube's opening compresses the rubber sealing ring 17, causing the rubber sealing ring 17 to undergo elastic deformation. This completely fills the annular gap between the outer wall of the air pipe 16 and the inner wall of the curved tube's opening, forming a reliable radial seal. Simultaneously, the end face of the curved tube's opening can fit against the axial end face of the rubber sealing ring 17, forming an axial limit, further improving the sealing effect and completely preventing helium leakage from the connection between the air pipe 16 and the curved tube's opening, ensuring the positive pressure stability of the curved tube's inner cavity.

[0063] To facilitate the insertion of the main rib curved tube opening into the outside of the gas tube 16, and to provide a stable flow direction for the helium gas, the following features are specifically provided:

[0064] like Figure 7 and Figure 8 As shown, a conical head 18 is coaxially inserted at the end of the trachea 16, and a one-way valve 19 is coaxially fixed to the conical head 18.

[0065] The one-way valve 19 is oriented from the inner cavity of the gas pipe 16 towards the outer side of the gas pipe 16. The conical outer wall of the conical head 18 provides guidance for the insertion of the main rib curved tube, facilitating rapid alignment and insertion of the curved tube into the outside of the gas pipe 16, significantly improving clamping efficiency. The one-way valve 19 automatically closes and blocks the airflow when the gas source 28 stops supplying gas, preventing outside air from flowing back into the inner cavity of the curved tube. This ensures that the weld bead remains in an inert gas protective atmosphere during the cooling process after welding, preventing high-temperature oxidation of the weld bead.

[0066] To prevent slippage between the tracheal tube 16 and the main rib curved tube opening during helium injection, the following features are specifically designed:

[0067] like Figure 8 and Figure 9 As shown, the outer wall of the trachea 16 is provided with equal-angled capacity grooves 20 along the circumferential direction. Each capacity groove 20 is slidably provided with a pad 23. The side of the pad 23 away from the capacity groove 20 is provided with anti-slip texture 24.

[0068] Each volumetric groove 20 is arranged with hollow tubes 21 at equal intervals along its long side. The hollow tubes 21 are dynamically sealed to the outer wall of the air pipe 16. The open end of the hollow tube 21 is connected to the inside of the air pipe 16, and the closed end is fixedly connected to the pad 23.

[0069] A second tension spring 22 is coaxially sleeved on the outside of the hollow tube 21. One end of the second tension spring 22 is fixedly connected to the capacity groove 20, and the other end is fixedly connected to the pad 23. When the gas source 28 continuously supplies helium to the inside of the gas tube 16, the hollow tube 21 drives the pad 23 to move away from the gas tube 16 under pressure until the pad 23 tightens the inner wall of the main rib curved tube opening.

[0070] When helium gas is introduced into the gas pipe 16 by the gas source 28, the positive pressure inside the gas pipe 16 pushes the hollow tube 21 to extend, causing the pad 23 to move outward and tighten the inner wall of the curved tube, thus achieving radial centering and anti-slip locking of the curved tube. When the gas source 28 stops supplying gas, the second tension spring 22 pulls the pad 23 to automatically return to its original position, releasing the tightening constraint.

[0071] To further fix the pipe opening of the main reinforcing duct, the following features are specifically designed:

[0072] like Figure 4 As shown, an electric gripper 25 is coaxially fitted around the outside of the air pipe 16. When the main rib curved pipe is inserted into the outside of the air pipe 16, the electric gripper 25 clamps the outer wall of the main rib curved pipe. After the end of the main rib curved pipe is inserted into the outside of the air pipe 16 and the inner wall is tightened and positioned, the electric gripper 25 drives the two jaws to close synchronously in opposite directions. The arc-shaped clamping surface completely fits the outer wall of the curved pipe, forming an internal and external opposing clamping with the inner pad 23, firmly locking the end of the curved pipe onto the air pipe 16. This completely avoids axial slippage of the curved pipe due to welding stress and internal air pressure impact during welding, further improving the reliability of clamping and positioning, and ensuring the coaxiality accuracy of the welded joint.

[0073] The detailed working principle of this device is as follows: Before operation, the operator first pre-adjusts and adapts the device according to the axial length, spatial trajectory, and clamping point requirements of the main rib curved pipe of the logistics vehicle to be welded. The electric pull-out plate 2 is driven to move, causing the core platform 3 to slide along the guide groove of the worktable 1 to the preset clamping position and automatically lock. Two sets of electric push rods 14 synchronously drive the slide table 13 to precisely move along the linear guide rail, adjusting the distance between the slide table 13 and the worktable 1 to match the overall size of the curved pipe. Finally, the lifting device 27 is driven to move, lifting the flexible plate 26 to the preset support height, completing the preliminary preparation.

[0074] The operator then guides the curved tube opening through the conical head 18 and quickly inserts it into the outside of the air pipe 16 on the worktable 1 and slide table 13. The inner wall of the curved tube end is compressed to form a seal with the rubber sealing ring 17, and the inner hole is centered using the air pipe 16 as a reference. Then, the air source 28 is pre-filled with low-pressure helium, which pushes the hollow tube 21 to drive the pad 23 to tighten the inner wall of the curved tube opening. Then, the electric gripper 25 is activated to clamp the outer wall of the curved tube opening from the outside, forming multiple locking constraints.

[0075] Simultaneously, the operator activates the bidirectional clamping mechanism 4. The first cylinder 5 drives the core frame 6 to move the main slider 7 axially, which in turn pushes the auxiliary slider 8 through the wedge transmission to move the outer expansion plate 9 outward to tighten the inner wall of the curved tube. At the same time, the second cylinder 11 drives the inner retracting plate 12 to move inward, cooperating with the outer expansion plate 9 to rigidly clamp the end of the curved tube from both the inner and outer sides. At the same time, the lifting device 27 moves the flexible plate 26 to fully fit against the lower wall of the curved tube, completing the auxiliary support of the suspended section and completely limiting the movement, swaying, and deformation of the curved tube during the welding process.

[0076] After clamping, the welding protection system is activated and welding operations are performed. High-pressure helium is continuously supplied through gas source 28. The helium is injected into the inner cavity of the curved tube through gas pipe 16, creating a stable positive pressure within the irregular pipe. This provides uniform radial support to the thin-walled tube wall, counteracting the shrinkage stress caused by welding heat input and the tendency for warping at bends, thus suppressing welding deformation at its source. Simultaneously, excess helium in the inner cavity is continuously and slowly released through pre-formed small holes on the side wall of the curved tube, creating a stable inert gas atmosphere around the welding point. This isolates oxygen from the air, preventing weld oxidation and poor weld pool formation. Throughout the welding process, the positive pressure support and inertial protection of the device operate continuously to ensure welding quality.

[0077] After welding is completed, the gas source 28 stops supplying gas, and the helium gas inside the curved tube is continuously depressurized through the small hole until it reaches zero. The one-way valve 19 automatically closes to prevent air backflow and ensures inertial protection during the weld cooling process. After the weld has completely cooled, the electric gripper 25 and the bidirectional clamping mechanism 4 are unlocked in sequence, and the slide table 13 moves and resets. Finally, the inner retracting plate 12, the outer expanding plate 9, and the lifting device 27 are driven to reset, and the finished curved tube can be removed to complete the welding operation.

[0078] The above embodiments only illustrate one or more implementations of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this patent should be determined by the appended claims.

Claims

1. A welding positioning device for the main reinforcing bars of a logistics vehicle, characterized in that, include: A fixed workbench (1) is provided. A core platform (3) is slidably provided on the upper end of the workbench (1). A bidirectional clamping mechanism (4) for clamping the end of the main rib curved tube is symmetrically provided on both sides of the core platform (3). The bidirectional clamping mechanism (4) includes an outer expansion plate (9) slidably connected to the core platform (3). An inner closing plate (12) is slidably provided on the side of the outer expansion plate (9) away from the core platform (3). The outer expansion plate (9) and the inner closing plate (12) respectively position the end of the main rib curved tube from both sides. A slide table (13) is slidably provided at one end of the workbench (1). Two gas sources (28) loaded with helium are respectively provided at the lower ends of the workbench (1) and the slide table (13). Two clamping mechanisms (15) for positioning the irregular pipes of the main rib are symmetrically provided at the upper ends of the workbench (1) and the upper ends of the slide table (13). The clamping mechanism (15) includes a gas pipe (16) connected to the gas source (28). The pipe opening of the main rib curved pipe is inserted into the outside of the gas pipe (16) during welding. The gas source (28) continuously supplies helium to the main rib curved pipe through the gas pipe (16) to provide it with pressure to resist deformation. Small holes are opened on the side wall of the main rib curved tube, and excess helium gas is released from the small holes to create an inert gas welding space for the welding points.

2. The main reinforcement welding positioning device for a logistics vehicle according to claim 1, characterized in that, Two lifting devices (27) are symmetrically arranged in the middle of the workbench (1). The output end of the lifting device (27) is set upward and is fixedly connected to a flexible plate (26).

3. The main reinforcement welding positioning device for a logistics vehicle according to claim 1, characterized in that, Below the core platform (3) is an electric pull plate (2) that is fixed to the upper end of the worktable (1), and the moving end of the electric pull plate (2) is fixed to the core platform (3).

4. The main reinforcement welding positioning device for a logistics vehicle according to claim 3, characterized in that, The bidirectional clamping mechanism (4) also includes a core frame (6) that is slidably connected to the inner wall of the core platform (3). The core frame (6) is hollow inside and is equipped with a first cylinder (5). The fixed end of the first cylinder (5) is fixedly connected to the core platform (3), and the output end is fixedly connected to the core frame (6). The core frame (6) has main sliders (7) fixedly connected in an equally spaced array along the long side on both sides. The core platform (3) has secondary sliders (8) slidably connected in an equally spaced array along the long side on both sides. The main sliders (7) and secondary sliders (8) are respectively formed with inclined surfaces on their corresponding and close sides. The main sliders (7) and secondary sliders (8) are slidably connected through the inclined surfaces. The outer expansion plate (9) is fixedly connected to the corresponding secondary slider (8) on the side close to the core stage (3). A first tension spring (10) is provided on the side close to the two adjacent secondary sliders (8). One end of the first tension spring (10) is fixedly connected to the outer expansion plate (9), and the other end is fixedly connected to the core stage (3).

5. The main reinforcement welding positioning device for a logistics vehicle according to claim 3, characterized in that, The inner plate (12) is inclined on the side away from the core platform (3) and a second cylinder (11) is fixedly connected to the worktable (1) through a support. The output end of the second cylinder (11) is fixedly connected to the inner plate (12).

6. The main reinforcement welding positioning device for a logistics vehicle according to claim 1, characterized in that, Two electric actuators (14) are symmetrically arranged at one end of the worktable (1) near the slide (13). The fixed end of the electric actuator (14) is fixedly connected to the upper end of the worktable (1), and the output end is fixedly connected to the upper end of the slide (13). The two sides of the slide (13) are slidably connected to the worktable (1) through guide rails.

7. The main reinforcement welding positioning device for a logistics vehicle according to claim 1, characterized in that, A rubber sealing ring (17) is coaxially fixed at the root of the trachea (16). When the main rib curved pipe is fitted at the root of the trachea (16), the rubber sealing ring (17) and the pipe opening of the main rib curved pipe are interference-fitted.

8. The main reinforcement welding positioning device for a logistics vehicle according to claim 7, characterized in that, A conical head (18) is coaxially inserted at the end of the trachea (16), and a one-way valve (19) is coaxially fixed to the conical head (18).

9. The main reinforcement welding positioning device for a logistics vehicle according to claim 7, characterized in that, The outer wall of the trachea (16) is provided with equal-angled capacity grooves (20) along the circumferential direction. Each capacity groove (20) is slidably provided with a pad (23). The side of the pad (23) away from the capacity groove (20) is provided with anti-slip texture (24). Each capacity groove (20) is arranged with hollow tubes (21) at equal intervals along its long side. The hollow tubes (21) are dynamically sealed to the outer wall of the air pipe (16). The open end of the hollow tube (21) is connected to the inside of the air pipe (16), and the closed end is fixedly connected to the pad (23). A second tension spring (22) is coaxially sleeved on the outside of the hollow tube (21). One end of the second tension spring (22) is fixedly connected to the capacity groove (20), and the other end is fixedly connected to the pad (23). When the gas source (28) continuously supplies helium to the inside of the gas tube (16), the hollow tube (21) moves the pad (23) away from the gas tube (16) under pressure until the pad (23) tightens the inner wall of the main rib curved tube.

10. A main reinforcement welding positioning device for a logistics vehicle according to claim 9, characterized in that, An electric gripper (25) is coaxially fitted on the outside of the trachea (16). When the main rib curved tube is inserted outside the trachea (16), the electric gripper (25) clamps the outer wall of the main rib curved tube.

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