Welding tool for cross beam of rear auxiliary frame of automobile

Abstract

The invention provides a welding tool for an automobile rear auxiliary frame cross beam, and belongs to the technical field of automobile cross beam welding, the welding tool comprises a base, a rear auxiliary frame main body, an operation table and a welding robot, and the operation table and the welding robot are arranged on the base, and the welding tool further comprises a positioning splicing assembly and a flow guide destressing assembly; protective gas is integrated on the third clamping jaw, the third clamping jaw can effectively guide protective gas flow to a welding seam while fixing the side cross beam, and effective flow guide of the protective gas can be achieved in cooperation with arrangement of the movable spraying pipe; during welding, the impeller is static to block gas, the flow speed is reduced, welding fluid is prevented from splashing and losing due to overlarge airflow impact, and stable combustion of welding arcs is maintained; in the cooling stage after welding is completed, the inductor controls the electromagnetic base to be powered off, gas flow is increased, the cooling speed is increased, meanwhile, vibration is generated to be matched with cooling to eliminate welding residual stress, the stability and reliability of a weldment are improved, the production period can be shortened, and the production efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of automotive crossbeam welding, and more particularly, to a welding tooling for the rear subframe crossbeam of an automobile. Background Art

[0002] The rear subframe crossbeam of an automobile refers to the transverse support element in the rear chassis structure of the automobile, which is composed of front and rear crossbeams and left and right crossbeams (as Figure 5 shown), and is usually used to connect the rear subframes on both sides of the vehicle body to enhance the stability and stiffness of the entire vehicle body. Such a crossbeam plays a crucial role in terms of safety and structural strength. The crossbeam connects the left and right sides of the rear subframe, which can effectively increase the load-bearing capacity and torsional bending resistance of the entire vehicle body and improve the structural strength of the vehicle.

[0003] When welding the rear subframe crossbeam of an automobile in the prior art, the following deficiencies exist: Firstly, the protection during the welding process is mostly achieved through an independent shielding gas input system. In the actual welding process, due to the poor adaptability of the shielding gas delivery pipeline layout to the welding area, the gas is easily interfered by external airflows during transmission, making it difficult to ensure that a sufficient amount of shielding gas is accurately and stably delivered to the weld area. This results in the difficulty of forming a continuous and uniform effective shielding gas curtain around the weld, making the weld metal at high temperature extremely likely to chemically react with oxygen, nitrogen, etc. in the air, resulting in oxidation, nitriding, etc. phenomena. This not only reduces the purity of the weld, but also causes a significant decline in the mechanical properties of the weld, such as key indicators like strength, toughness, and fatigue resistance, which cannot meet the stringent quality requirements of the rear subframe crossbeam of an automobile, seriously affecting the reliability and service life of the product; Secondly, the rear subframe crossbeam of an automobile is usually welded from various components with different materials, thicknesses, and shapes. During the welding process, due to the rapid heating and cooling cycles in local areas, complex and unevenly distributed residual stresses will inevitably be generated inside the welded part. Relying solely on natural cooling, the residual stresses continue to accumulate inside the welded part, making it extremely easy for the welded part to deform, affecting the dimensional accuracy and assembly performance of the product. Even if some conventional cooling methods such as simple air cooling and water cooling are used, it is difficult to fundamentally change the stress distribution state and effectively eliminate the welding stress concentration areas.

[0004] How to invent a welding tooling for the rear subframe crossbeam of an automobile to solve these problems has become an urgent problem for those skilled in the art. Summary of the Invention

[0005] To make up for the above deficiencies, the present invention provides a welding tooling for the rear subframe crossbeam of an automobile, aiming to solve the problems mentioned in the above background.

[0006] The present invention is implemented as follows:

[0007] The present invention provides a welding tooling for an automotive rear subframe crossbeam, including a base, a rear subframe main body, an operating table and a welding robot arranged on the base. The rear subframe main body includes a front crossbeam, a rear crossbeam and two side crossbeams connecting the two, and the two side crossbeams are symmetrically arranged left and right. Positioning holes are correspondingly provided on the front crossbeam, the rear crossbeam and the side crossbeams. The welding tooling further includes:

[0008] A positioning and splicing assembly: The positioning and splicing assembly is arranged on the operating table and is used to realize the splicing and positioning of the front crossbeam, the rear crossbeam and the two side crossbeams.

[0009] A flow guiding and stress relieving assembly: The flow guiding and stress relieving assembly is arranged inside the positioning and splicing assembly.

[0010] Preferably, the positioning and splicing assembly includes an electric sliding table, a mounting plate, a first jaw, a second jaw and two third jaws. The two third jaws are symmetrically distributed. A support seat is fixedly connected to the top of the electric sliding table. An installation groove matching the rotation path of the mounting plate and a sliding groove matching the electric sliding table are provided on the operating table. A connecting shaft is rotatably connected to the support seat, and the end of the connecting shaft is fixed to one side of the third jaw. The end of one of the connecting shafts is connected to an external driving mechanism. A motor, two slide rails and mounting seats are fixedly installed on the mounting plate. A lead screw is rotatably connected between the two mounting seats, and the output end of the motor is fixedly connected to the end of the lead screw.

[0011] Preferably, sliders and fixed sleeves are installed at the bottoms of the first jaw and the second jaw. The sliders are slidably connected to the slide rails. The lead screw is provided with two thread structures with opposite helix directions, and each thread is threadedly connected to one of the fixed sleeves respectively. The first jaw and the second jaw are symmetrically distributed along the demarcation point of the two reverse threads.

[0012] Preferably, the front crossbeam is positioned and fixed by the first jaw, the rear crossbeam is positioned and fixed by the second jaw, and the side crossbeam is positioned and fixed by the third jaw.

[0013] Preferably, slots are provided on both the first jaw and the second jaw. A limiting plate is movably clamped in the slot, and the limiting plate and the slot are magnetically connected. Clamping air bags are fixedly installed inside the first jaw and the second jaw. An air injection port is connected to the side wall of the clamping air bag, and the air injection port is connected to an external air pipeline. A first positioning mechanism for positioning the positioning hole on the front cross beam is fixedly provided on the first jaw. After positioning, the side wall of the front cross beam abuts against the side wall of the limiting plate on the first jaw. A second positioning mechanism for positioning the positioning hole on the rear cross beam is fixedly provided on the second jaw. After positioning, the side wall of the rear cross beam abuts against the side wall of the limiting plate on the second jaw. A positioning groove is provided on the third jaw. A gas guide plate is movably clamped in the positioning groove, and the gas guide plate and the positioning groove are magnetically connected. A third positioning mechanism for positioning the positioning hole on the side cross beam is provided inside the third jaw. After positioning, the side wall of the side cross beam abuts against the side wall of the gas guide plate.

[0014] Preferably, the cross-sectional profiles of the first jaw, the second jaw, and the third jaw are all U-shaped.

[0015] Preferably, the flow guiding stress relief assembly includes a gas storage cavity provided in the third jaw and a gas guiding cavity provided in the gas guide plate. Partition plates are provided inside the gas storage cavity and the gas guiding cavity, and their internal spaces are divided into two by the partition plates. Two protective gas injection ports are connected to the side wall of the third jaw, and the protective gas injection ports are communicated with the inner cavity of the gas storage cavity. The end of the protective gas injection port is communicated with an external protective gas delivery pipeline. A plurality of movable nozzles are movably connected to the side walls of the third jaw and the gas guide plate facing the weld. An air outlet groove is provided on the side wall of the gas storage cavity close to the positioning groove. An air inlet groove matching the air outlet groove is provided on the side wall of the gas guide plate. The air inlet groove is communicated with the inner cavity of the gas guiding cavity. When the gas guide plate fits against the bottom of the positioning groove, the air outlet groove and the air inlet groove are aligned, and a contact seal is formed between them at this time.

[0016] Preferably, the length of the movable nozzle exposed outside is positively correlated with the distance between its end and the weld.

[0017] Preferably, the flow guiding stress relief assembly further includes a fixed shaft and a plurality of fixed cylinders fixedly installed in the gas storage cavity. A through hole for installing the fixed cylinder is provided on the side wall of the third jaw away from the protective gas injection port. An impeller is rotatably connected to the fixed shaft. An electromagnetic seat is fixedly installed on the fixed shaft. A magnetic block is connected to the end of the impeller. A leakage hole is provided on the side wall of the fixed cylinder facing the impeller. A magnetic sliding seat is slidably connected inside the fixed cylinder. The magnetic sliding seat and the fixed cylinder are elastically connected by a spring. A ball is rotatably clamped inside one side of the magnetic sliding seat away from the impeller. A sensor is fixedly installed on the side wall of the third jaw facing the weld.

[0018] Preferably, the inductor is electrically connected to the electromagnetic seat on this side. When the electromagnetic seat is energized, the opposite surfaces of the electromagnetic seat and the magnetic block are magnetically set with different polarities. The end surface of the magnetic block away from the axis of the fixed shaft and the opposite surface of the magnetic sliding seat are magnetically set with the same polarity. When the magnetic block and the magnetic sliding seat face each other, the magnetic force between them is greater than the elastic force of the spring. In the initial state, the rolling balls are inside the fixed cylinder. When the magnetic block rotates, there is a gap between the magnetic block and the fixed cylinder. A plurality of the fixed cylinders are equidistantly distributed along the edge of the third jaw.

[0019] The beneficial effects of the present invention are as follows:

[0020] 1. During welding, the inductor cooperates with the electromagnetic seat, impeller, etc., controls the flow rate of the shielding gas based on the working state of the welding robot, makes the impeller static to block the gas, reduces the flow rate, avoids the splash loss of the welding liquid due to the impact of the large air flow, maintains the stable combustion of the welding arc, and ensures the welding stability and the quality of the weld formation; during the cooling stage after welding, the inductor controls the electromagnetic seat to cut off the power, the impeller rotates, reduces the blockage of the shielding gas, increases the gas flow rate, and accelerates the cooling speed. At the same time, the rotation of the impeller drives the magnetic block, interacts with the magnetic sliding seat, makes the rolling balls impact the side beam side wall, generates vibration to cooperate with cooling to eliminate the welding residual stress, improves the stability and reliability of the welded part, can also shorten the production cycle, and improve the production efficiency.

[0021] 2. The partition divides the space of the gas storage cavity, makes the flow paths of the shielding gas during welding and cooling independent, and realizes the control of the gas flow rate difference on both sides according to the requirements of different stages of welding and cooling. The small flow rate during welding ensures the welding quality, and the large flow rate during cooling promotes rapid cooling and stress elimination, meeting the different requirements for the gas flow rate in different stages.

[0022] 3. In this application, the shielding gas is integrated on the third jaw. While the third jaw realizes the fixation of the side beam, it can effectively guide the shielding gas flow to the weld. With the setting of the movable nozzle, it can realize the effective diversion of the shielding gas to form a stable shielding atmosphere around the weld, effectively prevent the oxidation of the weld metal, reduce welding defects such as pores, significantly improve the purity and mechanical properties of the weld, and compared with the traditional method, reduce the energy loss and diffusion of gas transmission, and improve the gas utilization rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, so they should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0024] Figure 1 is the overall structural schematic diagram of the present invention;

[0025] Figure 2 is a schematic structural diagram of the operating platform of the present invention;

[0026] Figure 3 is a schematic structural diagram of the positioning and splicing component of the present invention;

[0027] Figure 4 is a schematic top view structural diagram of the positioning and splicing component of the present invention;

[0028] Figure 5 is a schematic structural diagram of the rear subframe main body of the present invention;

[0029] Figure 6 is a schematic partial explosion structural diagram of the present invention;

[0030] Figure 7 is a schematic structural diagram of the first jaw and the second jaw of the present invention;

[0031] Figure 8 is a schematic structural diagram of the third jaw and the air guide plate of the present invention;

[0032] Figure 9 is a schematic cross-sectional structural diagram of the third jaw of the present invention;

[0033] Figure 10 is of the present invention Figure 9 schematic enlarged structural diagram at position A in;

[0034] Figure 11 is a schematic front view of the cross-sectional structure of the third jaw of the present invention;

[0035] Figure 12 is a schematic structural diagram of the installation position of the electromagnetic seat of the present invention;

[0036] Figure 13 is a schematic structural diagram of the installation position of the partition of the present invention.

[0037] In the figure: 1, base; 2, rear subframe main body; 3, electric slide table; 4, mounting plate; 5, clamping airbag; 6, third jaw; 7, air guide plate; 8, movable nozzle; 9, air storage cavity; 10, operating platform; 11, welding robot; 21, front crossbeam; 22, rear crossbeam; 23, side crossbeam; 31, support seat; 32, connecting shaft; 41, first jaw; 42, second jaw; 43, limiting plate; 44, slide rail; 45, motor; 46, mounting seat; 51, air injection port; 60, positioning groove; 61, third positioning mechanism; 62, inductor; 63, protective gas injection port; 70, air guide cavity; 71, air inlet groove; 91, fixed shaft; 92, impeller; 93, fixed cylinder; 94, spring; 95, magnetic slide seat; 96, electromagnetic seat; 97, partition; 101, chute; 102, mounting groove; 411, first positioning mechanism; 421, second positioning mechanism; 431, slot; 441, slider; 451, lead screw; 601, air outlet groove; 921, magnetic block; 931, leakage hole; 951, ball. Detailed implementation manners

[0038] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0039] Example 1. Refer to Figures 1-8 , a welding tool for an automotive rear subframe crossbeam, including a base 1, a rear subframe main body 2, an operating platform 10 and a welding robot 11 arranged on the base 1. The rear subframe main body 2 includes a front crossbeam 21, a rear crossbeam 22 and two side crossbeams 23 connecting the two. The two side crossbeams 23 are symmetrically arranged left and right. Positioning holes are correspondingly provided on the front crossbeam 21, the rear crossbeam 22 and the side crossbeams 23. It further includes:

[0040] A positioning and splicing assembly: The positioning and splicing assembly is arranged on the operating platform 10 and is used to realize the splicing and positioning of the front crossbeam 21, the rear crossbeam 22 and the two side crossbeams 23;

[0041] A flow guiding and stress relieving assembly: The flow guiding and stress relieving assembly is arranged inside the positioning and splicing assembly.

[0042] Further, the positioning and splicing assembly includes an electric slide table 3, a mounting plate 4, a first jaw 41, a second jaw 42 and two third jaws 6. The two third jaws 6 are symmetrically distributed. A support base 31 is fixedly connected to the top of the electric slide table 3. An installation groove 102 matching the rotation path of the mounting plate 4 and a chute 101 matching the electric slide table 3 are provided on the operation table 10. A connecting shaft 32 is rotatably connected to the support base 31. The end of the connecting shaft 32 is fixed to one side of the third jaw 6. By controlling the electric slide table 3, the support base 31 and the connecting shaft 32 thereon can be moved, so as to control the movement of the corresponding third jaw 6. The end of one of the connecting shafts 32 is connected to an external driving mechanism (not shown in the figure, a servo motor or a stepping motor can be used and connected to the end of the connecting shaft 32 through a coupling device, etc.). After the welding on one side is completed, the rear subframe body 2 can be flipped by the external driving mechanism to complete the welding work on the other side. A motor 45, two slide rails 44 and a mounting seat 46 are fixedly installed on the mounting plate 4. A lead screw 451 is rotatably connected between the two mounting seats 46. The output end of the motor 45 is fixedly connected to the end of the lead screw 451.

[0043] It should be noted that sliders 441 and fixed sleeves are installed at the bottoms of the first jaw 41 and the second jaw 42. The sliders 441 are slidably connected to the slide rails 44. The lead screw 451 is provided with two thread structures with opposite helix directions. Each thread is threadedly connected to one of the fixed sleeves respectively. The first jaw 41 and the second jaw 42 are symmetrically distributed along the demarcation point of the two reverse threads. With the above settings, when the motor 45 is started, since the lead screw 451 has two thread structures with opposite helix directions, the first jaw 41 and the second jaw 42 can approach or move away from each other simultaneously, which is convenient for positioning and fixing the front cross beam 21 and the rear cross beam 22.

[0044] The front cross beam 21 is positioned and fixed by the first jaw 41, the rear cross beam 22 is positioned and fixed by the second jaw 42, and the side cross beam 23 is positioned and fixed by the third jaw 6. The cross-sectional profiles of the first jaw 41, the second jaw 42 and the third jaw 6 are all U-shaped, which can better fit and fix the cross beam components.

[0045] Furthermore, slots 431 are provided on both the first jaw 41 and the second jaw 42. A limiting plate 43 is movably clamped in the slot 431, and the limiting plate 43 is magnetically connected to the slot 431, which is convenient for installation and disassembly. Clamping air bags 5 are fixedly installed inside both the first jaw 41 and the second jaw 42. An air injection port 51 is connected to the side wall of the clamping air bag 5, and the air injection port 51 is connected to an external air pipeline. The clamping air bag 5 inside the jaw is connected to the external air pipeline through the air injection port 51. After inflation, it can further clamp the cross beam and enhance the positioning stability. A first positioning mechanism 411 for positioning the positioning hole on the front cross beam 21 is fixedly provided on the first jaw 41, and after positioning, the side wall of the front cross beam 21 abuts against the side wall of the limiting plate 43 on the first jaw 41. A second positioning mechanism 421 for positioning the positioning hole on the rear cross beam 22 is fixedly provided on the second jaw 42, and after positioning, the side wall of the rear cross beam 22 abuts against the side wall of the limiting plate 43 on the second jaw 42. A positioning groove 60 is provided on the third jaw 6. A guide air plate 7 is movably clamped in the positioning groove 60, and the guide air plate 7 is magnetically connected to the positioning groove 60. A third positioning mechanism 61 for positioning the positioning hole on the side cross beam 23 is provided inside the third jaw 6, and after positioning, the side wall of the side cross beam 23 abuts against the side wall of the guide air plate 7. The first positioning mechanism 411, the second positioning mechanism 421 and the third positioning mechanism 61 respectively position the positioning holes on the front cross beam 21, the rear cross beam 22 and the side cross beam 23 to ensure accurate splicing of each component. After positioning, the side wall of the rear cross beam 22 abuts against the side wall of the limiting plate 43 (the first jaw 41, the second jaw 42) or the side wall of the guide air plate 7 (the third jaw 6) to ensure the splicing accuracy.

[0046] In this embodiment, the welding tooling for the cross beam of the rear subframe of the vehicle is based on the base 1. The operating table 10 is used to carry the positioning and splicing assembly, and the welding robot 11 is responsible for welding the rear subframe body 2. The rear subframe body 2 is composed of a front cross beam 21, a rear cross beam 22 and two symmetric side cross beams 23, and positioning holes are provided on each cross beam for subsequent positioning and splicing.

[0047] The electric sliding table 3 can move along the sliding groove 101 on the operating table 10. The connecting shaft 32 on the support seat 31 at the top of the electric sliding table 3 is connected to the third jaw 6. By moving the electric sliding table 3, the position of the third jaw 6 can be controlled to make it close to or far away from the side cross beam 23. When the third jaw 6 reaches the appropriate position, the third positioning mechanism 61 inside the third jaw 6 will position the positioning hole on the side cross beam 23, and then insert the guide air plate 7 and fix it magnetically. At this time, the side wall of the side cross beam 23 abuts against the side wall of the guide air plate 7 to realize the preliminary positioning of the side cross beam 23.

[0048] When the motor 45 starts, the first jaw 41 and the second jaw 42 will approach or move away from each other simultaneously. During the approaching process, the first positioning mechanism 411 on the first jaw 41 positions the positioning hole on the front crossbeam 21, and then inserts the limiting plate 43 and fixes it by magnetic attraction. After positioning, the side wall of the front crossbeam 21 abuts against the side wall of the limiting plate 43 on the first jaw 41. Similarly, the second positioning mechanism 421 on the second jaw 42 positions the positioning hole on the rear crossbeam 22, then inserts the limiting plate 43 and fixes it by magnetic attraction. The side wall of the rear crossbeam 22 abuts against the side wall of the limiting plate 43 on the second jaw 42, thus completing the positioning of the front crossbeam 21 and the rear crossbeam 22. When the preliminary positioning of the crossbeams is completed, air is injected into the clamping airbag 5 through the air injection port 51, and the airbag expands to further clamp the crossbeams, enhancing the stability of the positioning.

[0049] After the positioning of the front crossbeam 21, the rear crossbeam 22 and the side crossbeam 23 is completed, the preliminary splicing operation begins. The motor 45 and the electric slide table 3 are used to control the crossbeam components to approach each other to complete the preliminary splicing of the rear subframe body 2, ensuring that the crossbeam components are in the correct relative positions before welding, laying a foundation for the subsequent welding operation, and ensuring the structural accuracy and dimensional accuracy of the welded rear subframe body 2. After the preliminary splicing of the rear subframe body 2 is completed, the welding robot 11 starts the welding work on this side and can weld the welds of the rear subframe body 2 according to the preset welding procedures and trajectories.

[0050] Through the welding of the welding robot 11, the front crossbeam 21, the rear crossbeam 22 and the side crossbeam 23 are firmly connected together, and the rear subframe body 2 is initially formed into a complete main body structure, with a certain strength and stability. After the welding on this side is completed, the rear subframe body 2 is initially formed into a main body, and then an external driving mechanism (such as a motor driving mechanism, a hydraulic driving mechanism or a pneumatic driving mechanism, etc.) is used to control the rotation of the rear subframe body 2 to turn the rear subframe body 2 to a suitable position for welding on the other side.

[0051] Positioning holes on the front crossbeam 21, rear crossbeam 22, and side crossbeam 23 are positioned by the positioning mechanisms on each jaw, and the side wall of the crossbeam abuts against the limiting plate 43 or the side wall of the air guide plate 7, ensuring the precise position of each crossbeam during splicing. This enables the rear subframe body 2 to have a high positional accuracy before welding, reduces welding errors caused by inaccurate splicing, improves the structural accuracy and dimensional accuracy of the entire rear subframe body 2, and thus enhances the product quality; the limiting plate 43 and the air guide plate 7 are magnetically fixed, which is not only convenient for installation and disassembly but also provides a stable fixing effect during the positioning process, ensuring the accuracy and reliability of positioning. This method is more convenient when adjusting and replacing components, improving the utilization efficiency of the tooling; the electric slide table 3 can control the position of the third jaw 6, and the motor 45 can drive the first jaw 41 and the second jaw 42 to approach or move away simultaneously. This design makes the tooling highly flexible when positioning rear subframe crossbeams of different sizes or specifications. The operator can quickly adjust the positions of each jaw according to actual needs to adapt to different production tasks, improving the versatility and production efficiency of the tooling.

[0052] Embodiment 2, referring to Figures 4-13 , the gas flow stress relief assembly includes an air storage cavity 9 opened in the third jaw 6 and a gas guide cavity 70 opened in the air guide plate 7. The gas flow stress relief assembly mainly has two core functions. One is to achieve the diversion of the shielding gas, providing a good shielding atmosphere for the welding process; the other is to use magnetic force and mechanical structure to generate vibration to relieve stress on the weld, thereby improving the welding quality and the stability of the welded parts. Partition plates 97 are provided inside both the air storage cavity 9 and the gas guide cavity 70, and their internal spaces are divided into two by the partition plates 97. Two shielding gas injection ports 63 are connected to the side wall of the third jaw 6. The shielding gas injection ports 63 are communicated with the inner cavity of the air storage cavity 9, and the end of the shielding gas injection port 63 is communicated with the external shielding gas delivery pipeline. The shielding gas injection port 63 is the channel for the shielding gas to enter the assembly, ensuring continuous and stable supply of shielding gas to the welding area. A plurality of movable nozzles 8 are movably connected to the side walls of the third jaw 6 and the air guide plate 7 facing the weld. An air outlet groove 601 is opened on the side wall of the air storage cavity 9 close to the positioning groove 60. An air inlet groove 71 matching the air outlet groove 601 is opened on the side wall of the air guide plate 7. The air inlet groove 71 is communicated with the inner cavity of the gas guide cavity 70. When the air guide plate 7 is in contact with the bottom of the positioning groove 60, the air outlet groove 601 is aligned with the air inlet groove 71, and a contact seal is formed between them at this time, ensuring that the shielding gas can flow smoothly from the air storage cavity 9 into the gas guide cavity 70.

[0053] Furthermore, the diversion stress relief component further includes a fixed shaft 91 and a number of fixed cylinders 93 fixedly installed in the gas storage cavity 9. A through hole for installing the fixed cylinder 93 is provided on the side wall of the third jaw 6 away from the protective gas injection port 63. An impeller 92 is rotatably connected to the fixed shaft 91, and an electromagnetic seat 96 is fixedly installed on the fixed shaft 91. A magnetic block 921 is connected to the end of the impeller 92. When the electromagnetic seat 96 is not powered on, the flow of the protective gas drives the impeller 92 to rotate, and the magnetic block 921 rotates accordingly. Leak holes 931 are provided on the side wall of the fixed cylinder 93 facing the impeller 92 to ensure effective transmission of magnetic force. A magnetic sliding seat 95 is slidably connected inside the fixed cylinder 93, and the magnetic sliding seat 95 is elastically connected to the fixed cylinder 93 through a spring 94. A ball 951 is rotatably clamped inside one side of the magnetic sliding seat 95 away from the impeller 92, and a sensor 62 is fixedly installed on the side wall of the third jaw 6 facing the weld. The sensor 62 is used to sense whether the welding robot 11 is in a welding state.

[0054] It should be noted that the length of the movable nozzle 8 exposed outside is positively correlated with the distance between its end and the weld seam. The gas injection angle and range can be flexibly adjusted according to the actual welding situation to accurately cover the weld seam area. The inductor 62 is electrically connected to the electromagnetic seat 96 on this side. The inductor 62 transmits the sensed signal to the electromagnetic seat 96 to control the energized state of the electromagnetic seat 96. When the welding robot 11 welds this side, the electromagnetic seat 96 on this side is energized, and vice versa. When the electromagnetic seat 96 is energized, the opposite faces of the electromagnetic seat 96 and the magnetic block 921 are set with different polar magnetisms. At this time, the electromagnetic seat 96 firmly attracts the magnetic block 921, and the impeller 92 cannot rotate, which can initially block the shielding gas introduced from the shielding gas injection port 63 to reduce the flow rate of the shielding gas during welding and prevent the weld metal from flowing out of the welding area. The end face of the magnetic block 921 far from the axis of the fixed shaft 91 and the opposite face of the magnetic slide seat 95 are set with the same polar magnetism. When the magnetic block 921 and the magnetic slide seat 95 are facing each other, the magnetic force between them is greater than the elastic force of the spring 94. In the initial state, the ball 951 is inside the fixed cylinder 93. When the welding on this side is completed, the other side enters the welding state and this side is in the cooling state. At this time, the shielding gas is still being ejected. However, since the welding robot 11 is far from this side, the inductor 62 on this side will control the electromagnetic seat 96 on this side to be de-energized. At this time, under the push of the shielding gas flow, the impeller 92 will rotate. On the one hand, since the rotating impeller 92 is in a moving state, its blockage of the shielding gas flow becomes smaller, and the flow rate of the shielding gas increases accordingly, accelerating the cooling process. On the other hand, when the impeller 92 rotates, the magnetic block 921 on it also rotates. When the magnetic block 921 rotates to face the magnetic slide seat 95, the magnetic force generated by the same polar magnetism is greater than the elastic force of the spring 94, pushing the magnetic slide seat 95 to slide, causing the ball 951 to protrude from the fixed cylinder 93 and hit the side wall of the side cross beam 23. The generated vibration will be transmitted to the weld seam area to eliminate the welding residual stress, and then move away and reset under the action of the spring 94. As the impeller 92 rotates continuously, the above process will be repeated continuously. There is a gap between the magnetic block 921 and the fixed cylinder 93 when the magnetic block 921 rotates to avoid movement interference. A number of fixed cylinders 93 are evenly distributed along the edge of the third jaw 6 to ensure uniform transmission of the vibration force.

[0055] In this embodiment, the external shielding gas enters the gas storage cavity 9 through two shielding gas injection ports 63 on the side wall of the third jaw 6. The partition 97 in the gas storage cavity 9 divides its space into two parts, which helps the gas to be more evenly distributed and flow. When the air guide plate 7 fits against the bottom of the positioning groove 60 of the third jaw 6, the air outlet groove 601 on the side wall of the gas storage cavity 9 is aligned with the air inlet groove 71 on the side wall of the air guide plate 7 and forms a contact seal. In this way, the shielding gas flows from the gas storage cavity 9 into the air inlet groove 71 through the air outlet groove 601, and then enters the air guide cavity 70. The movable nozzle 8 on the side walls of the third jaw 6 and the air guide plate 7 facing the weld has an exposed length that is positively correlated with the distance between its end and the weld. According to the actual welding situation, the movable nozzle 8 can flexibly adjust the gas injection angle and range, and accurately inject the shielding gas into the weld area, forming a good shielding atmosphere around the weld to prevent the weld metal from being oxidized.

[0056] During welding: The inductor 62 senses whether the welding robot 11 is in the welding state. When the welding robot 11 welds one side, the inductor 62 on that side transmits a signal to the electromagnetic seat 96, causing the electromagnetic seat 96 to be energized. At this time, the opposite surfaces of the electromagnetic seat 96 and the magnet 921 are set with different polar magnetisms, and the electromagnetic seat 96 will firmly attract the magnet 921, making the impeller 92 connected to the magnet 921 unable to rotate. At this time, the impeller 92 is in a stationary state, and its blades will form a greater blocking effect on the shielding gas flowing from the shielding gas injection port 63 into the gas storage cavity 9. This blocking causes the flow of the shielding gas to be restricted when passing through the area where the impeller 92 is located, the gas flow rate is reduced, and the amount of gas passing through per unit time is reduced, that is, the shielding gas flow rate is smaller. In this way, the shielding gas introduced from the shielding gas injection port 63 is initially blocked, and the flow rate of the shielding gas during welding is reduced, avoiding the welding liquid from flowing out of the welding area due to too fast gas flow rate, and ensuring the welding quality.

[0057] After welding (during cooling): When the welding on one side is completed and the other side enters the welding state while this side is in the cooling state, since the welding robot 11 is far from this side, the inductor 62 on this side will control the power-off of the electromagnetic seat 96 on this side. At this time, under the push of the protective air flow, the impeller 92 starts to rotate. On the one hand, as the impeller 92 rotates, the relative angle between its blades and the flow direction of the protective gas continuously changes. Compared with the static state, the blades of the rotating impeller 92 no longer completely block the flow path of the protective gas as before, and the gas can pass more smoothly between or around the blades. The blocking of the rotating impeller 92 on the protective air flow becomes smaller, making the flow rate of the protective gas increase correspondingly and accelerating the cooling process on this side. On the other hand, when the impeller 92 rotates, the magnetic block 921 at its end also rotates. When the magnetic block 921 rotates to face the magnetic sliding seat 95, since the opposite surfaces of the magnetic block 921 and the magnetic sliding seat 95 are of the same-pole magnetism, the magnetic force between the two is greater than the elastic force of the spring 94, which will push the magnetic sliding seat 95 to slide, causing the ball 951 to protrude from the fixed cylinder 93 and hit the side wall of the side cross beam 23. The generated vibration is transmitted to the weld area, thereby eliminating the welding residual stress. Subsequently, the magnetic block 921 rotates away from the magnetic sliding seat 95, and the magnetic sliding seat 95 resets under the action of the spring 94. As the impeller 92 continues to rotate, the above process will be continuously repeated. A number of fixed cylinders 93 are evenly distributed along the edge of the third jaw 6 to ensure that the vibration force can be evenly transmitted to the weld area.

[0058] It should be noted that during the welding process, high temperature will melt the welding material to form liquid welding fluid. If the shielding gas flow is too large at this time, it may produce a strong impact force, causing the liquid welding fluid to be blown away or blown out of the welding area, causing the welding fluid to splash and lose, affecting the welding quality, and failing to form a good weld. A smaller airflow can provide a protective atmosphere while avoiding excessive interference with the welding fluid, ensuring the stability of welding and the quality of weld formation. The welding arc needs to be in a stable environment to burn normally. Excessive airflow may disrupt the electric field and thermal field distribution around the arc, making the arc unstable and even causing the arc to go out. A smaller airflow helps to maintain the stable burning of the arc, provide a continuous heat source for the welding process, and ensure the smooth progress of welding. After welding, the weldment is in a high temperature state. Rapid cooling can stabilize the metal structure of the weld and heat-affected zone as quickly as possible, reduce high-temperature residence time, avoid defects such as grain growth, and improve the mechanical properties of the weld. A larger airflow can increase the heat exchange efficiency between the weld and the shielding gas, take away more heat, and thus speed up the cooling rate. Residual stress will be generated inside the weld during the welding process. If the cooling rate is too slow, the residual stress may accumulate inside the weld, causing the weld to deform or even crack. A larger airflow speeds up the cooling rate, which can make the various parts of the weld shrink evenly, reduce stress concentration, reduce the impact of residual stress, and improve the stability and reliability of the weld. Accelerating the cooling rate can enable the weld to reach the temperature conditions for the next process more quickly, shorten the production cycle, and improve production efficiency.

[0059] The present application integrates the shielding gas on the third clamp 6. The third clamp 6 can effectively guide the shielding gas flow to the weld while fixing the side cross beam 23. Combined with the setting of the movable nozzle 8, it can realize effective flow guidance of the shielding gas to form a stable protective atmosphere around the weld. The integration of such functions enables the shielding gas to act on the welding area more directly and efficiently. Compared with the traditional shielding gas supply method, it reduces the energy loss and diffusion of the gas during the transmission process, improves the utilization rate of the shielding gas, effectively prevents the weld metal from being oxidized, reduces the generation of welding defects such as pores, and improves the purity and mechanical properties of the weld.

[0060] In addition, the partition plate 97 divides the space of the gas storage cavity 9 into two parts, separating the flow path of the protective gas into two relatively independent parts. During the welding process, one side of the impeller 92 is stationary under the action of the electromagnetic seat 96, forming a large blockage to the gas, resulting in a smaller gas flow rate on that side; while during cooling, the electromagnetic seat 96 is powered off, the impeller 92 rotates, the blockage to the gas becomes smaller, and the gas flow rate becomes larger. Due to the presence of the partition plate 97, this change in gas flow rate is restricted within their respective regions, that is, the gas flows on both sides do not interfere with each other, thus realizing the differential control and mutual independence of the gas flow rates during welding and cooling. According to the requirements of different stages of welding and cooling, the gas flow rates on both sides can be precisely adjusted. During welding, a smaller gas flow rate can prevent the welding liquid from flowing out of the welding area due to excessive air flow, ensuring the welding quality; during cooling, a larger gas flow rate can accelerate the cooling speed, improve the mechanical properties of the welded part, and reduce problems such as residual stress.

[0061] It should be noted that the specific model specifications of the motor 45, the electric slide table 3, etc. need to be selected and determined according to the actual specifications of the device. The specific selection calculation method adopts the existing technology in this field, so it will not be elaborated in detail.

[0062] The above is only the preferred embodiment of the present invention and is not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A welding tooling for the rear crossbeam of an automobile rear subframe, comprising a base (1), a rear subframe main body (2), an operating table (10) and a welding robot (11) arranged on the base (1). The rear subframe main body (2) includes a front crossbeam (21), a rear crossbeam (22) and two side crossbeams (23) connecting the two. The two side crossbeams (23) are symmetrically arranged left and right. Positioning holes are correspondingly provided on the front crossbeam (21), the rear crossbeam (22) and the side crossbeams (23). It is characterized in that, Further included are: A positioning and splicing component: The positioning and splicing component is arranged on the operation table (10); A diversion and stress relief component: The diversion and stress relief component is arranged inside the positioning and splicing component.

2. The welding tooling for the rear subframe crossbeam of an automobile according to claim 1, characterized in that, The positioning and splicing component includes an electric slide table (3), a mounting plate (4), a first jaw (41), a second jaw (42) and two third jaws (6). The two third jaws (6) are symmetrically distributed. A support seat (31) is fixedly connected to the top of the electric slide table (3). An installation groove (102) matching the rotation path of the mounting plate (4) and a sliding groove (101) matching the electric slide table (3) are provided on the operation table (10). A connecting shaft (32) is rotatably connected to the support seat (31). The end of the connecting shaft (32) is fixed to one side of the third jaw (6). The end of one of the connecting shafts (32) is connected to an external driving mechanism. A motor (45), two slide rails (44) and a mounting seat (46) are fixedly installed on the mounting plate (4). A lead screw (451) is rotatably connected between the two mounting seats (46). The output end of the motor (45) is fixedly connected to the end of the lead screw (451).

3. A welding tooling for the rear subframe crossbeam of an automobile according to claim 2, characterized in that, Sliders (441) and fixing sleeves are installed at the bottoms of the first jaw (41) and the second jaw (42). The sliders (441) are slidably connected to the slide rails (44). Two thread structures with opposite helix directions are provided on the lead screw (451). Each section of the thread is threadedly connected to one of the fixing sleeves respectively. The first jaw (41) and the second jaw (42) are symmetrically distributed along the demarcation point of the two sections of reverse threads.

4. The welding tooling for the rear subframe crossbeam of an automobile according to claim 2, characterized in that, The front cross beam (21) is positioned and fixed by the first jaw (41), the rear cross beam (22) is positioned and fixed by the second jaw (42), and the side cross beam (23) is positioned and fixed by the third jaw (6).

5. The welding tooling for the rear subframe crossbeam of an automobile according to claim 2, characterized in that, The first jaw (41) and the second jaw (42) are both provided with slots (431). A limiting plate (43) is movably clamped in the slots (431). The limiting plate (43) and the slots (431) are magnetically connected. Inside the first jaw (41) and the second jaw (42), a clamping airbag (5) is fixedly installed. A gas injection port (51) is connected to the side wall of the clamping airbag (5). The gas injection port (51) is connected to an external gas pipeline. The first jaw (41) is fixedly provided with a first positioning mechanism (411) for positioning the positioning hole on the front cross beam (21). After positioning, the side wall of the front cross beam (21) abuts against the side wall of the limiting plate (43) on the first jaw (41). The second jaw (42) is fixedly provided with a second positioning mechanism (421) for positioning the positioning hole on the rear cross beam (22). After positioning, the side wall of the rear cross beam (22) abuts against the side wall of the limiting plate (43) on the second jaw (42). The third jaw (6) is provided with a positioning groove (60). A gas guide plate (7) is movably clamped in the positioning groove (60). The gas guide plate (7) and the positioning groove (60) are magnetically connected. Inside the third jaw (6), a third positioning mechanism (61) for positioning the positioning hole on the side cross beam (23) is provided. After positioning, the side wall of the side cross beam (23) abuts against the side wall of the gas guide plate (7).

6. The welding tooling for the rear subframe crossbeam of an automobile according to claim 2, characterized in that, The cross-sectional profiles of the first jaw (41), the second jaw (42) and the third jaw (6) are all U-shaped.

7. The welding tooling for the rear subframe crossbeam of an automobile according to claim 5, characterized in that The flow guiding and stress relieving assembly includes an air storage cavity (9) opened in the third jaw (6) and a gas guide cavity (70) opened in the gas guide plate (7). Inside the air storage cavity (9) and the gas guide cavity (70), a partition plate (97) is provided, and the internal space is divided into two by the partition plate (97). Two protective gas injection ports (63) are connected to the side wall of the third jaw (6). The protective gas injection ports (63) are communicated with the inner cavity of the air storage cavity (9). The end of the protective gas injection port (63) is communicated with an external protective gas pipeline. A plurality of movable nozzles (8) are movably connected to the side walls of the third jaw (6) and the gas guide plate (7) facing the weld. An air outlet groove (601) is opened on the side wall of the air storage cavity (9) close to the positioning groove (60). An air inlet groove (71) matching the air outlet groove (601) is opened on the side wall of the gas guide plate (7). The air inlet groove (71) is communicated with the inner cavity of the gas guide cavity (70). When the gas guide plate (7) fits against the bottom of the positioning groove (60), the air outlet groove (601) is aligned with the air inlet groove (71), and a contact seal is formed between the two at this time.

8. A welding tooling for the rear subframe crossbeam of an automobile according to claim 7, characterized in that, The length of the movable nozzle (8) exposed outside is positively correlated with the distance between its end and the weld.

9. The welding tooling for the rear subframe crossbeam of an automobile according to claim 7, characterized in that, The flow guiding stress relieving assembly further includes a fixed shaft (91) and a number of fixed cylinders (93) fixedly installed in the gas storage cavity (9). A through hole for installing the fixed cylinder (93) is provided on the side wall of the third jaw (6) away from the protective gas injection port (63). An impeller (92) is rotatably connected to the fixed shaft (91). An electromagnetic seat (96) is fixedly installed on the fixed shaft (91). A magnetic block (921) is connected to the end of the impeller (92). Leak holes (931) are provided on the side wall of the fixed cylinder (93) facing the impeller (92). A magnetic sliding seat (95) is slidably connected inside the fixed cylinder (93). The magnetic sliding seat (95) is elastically connected to the fixed cylinder (93) by a spring (94). A ball (951) is rotatably clamped inside one side of the magnetic sliding seat (95) away from the impeller (92). An inductor (62) is fixedly installed on the side wall of the third jaw (6) facing the weld seam.

10. A welding tool for an automotive rear subframe crossbeam according to claim 9, characterized in that, The inductor (62) is electrically connected to the electromagnetic seat (96) on this side. When the electromagnetic seat (96) is energized, the opposite surfaces of the electromagnetic seat (96) and the magnetic block (921) are set with different polar magnetisms. The opposite surfaces between the end face of the magnetic block (921) away from the axis of the fixed shaft (91) and the magnetic sliding seat (95) are set with the same polar magnetism. When the magnetic block (921) and the magnetic sliding seat (95) are facing each other, the magnetic force between them is greater than the elastic force of the spring (94). In the initial state, the ball (951) is inside the fixed cylinder (93). There is a gap between the magnetic block (921) and the fixed cylinder (93) when the magnetic block (921) rotates. The several fixed cylinders (93) are equidistantly distributed along the edge of the third jaw (6).

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