Automobile subframe welding system and welding method

Abstract

The present invention relates to a welding system and method for an automobile subframe. The welding system includes a first welding workstation, a second welding workstation, a third welding workstation, and a repair welding tool, each of which is arranged in parallel. A turntable is provided on each of the first welding workstation, the second welding workstation, and the third welding workstation. Two sets of positioners are provided on the turntable, each of which is connected to a workbench, and each workbench is provided with a clamping fixture. A welding robot that cooperates with a corresponding workbench is provided on the turntable, and hoists for lifting parts are distributed in the welding workstation. The present invention realizes the automated welding and forming of the automobile subframe. After welding at the welding workstation, manual repair welding is performed to ensure the quality of the final product. At the same time, through the coordination of the positioner, turntable, and clamping fixture, the welding of the subframe assembly and the welding of the various subframe components can be circulated within the same welding production line, thereby reducing the welding cycle and improving welding efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of automobile subframe production and processing, in particular to an automobile subframe welding system and a welding method. Background Art

[0002] The automotive subframe is a crucial component of the vehicle's body-in-white (BIW), supporting the engine and various underbody components. Traditionally, subframe production involves multiple assembly lines for welding, resulting in long production cycles and low efficiency. With the increasing adoption of automation technology, automated production lines are increasingly being used in automotive parts production to improve production efficiency and welding precision. To adapt to automated production, a subframe welding system and method were designed and developed. Summary of the Invention

[0003] In order to solve the above technical problems, the present invention proposes an automobile subframe welding system and welding method. The technical problems to be solved by the present invention are achieved by adopting the following technical solutions:

[0004] An automobile subframe welding system includes a first welding workstation, a second welding workstation, a third welding workstation, and a repair welding tool, each of which is arranged in parallel. A turntable is provided in each of the first welding workstation, the second welding workstation, and the third welding workstation. Two sets of No. 1 positioners are provided on the turntable. The No. 1 positioners are connected to a worktable, and a clamping fixture is provided on the worktable.

[0005] The turntable is provided with a welding robot that cooperates with the corresponding workbench, and the welding workstation is provided with lifting equipment for lifting parts.

[0006] The clamping fixture on the workbench on one side of the third welding workstation includes a No. 1 clamp assembly installed on the workbench and used to fix the front subframe assembly. The workbench is provided with a No. 2 clamp assembly symmetrically distributed along the length direction of the workbench to fix the left and right front mounting brackets of the control arm. The workbench is also provided with a No. 3 clamp assembly symmetrically distributed along the length direction of the workbench to enable the left and right front mounting bracket assemblies of the control arm to cooperate with the front subframe assembly.

[0007] The second clamp assembly includes a No. 1 positioning pin that passes through the front mounting bracket of the control arm and is mounted on the workbench. The No. 1 positioning pin is matched with a No. 1 limiting portion on the workbench to engage with the front mounting bracket of the control arm to limit the horizontal position of the front mounting bracket of the control arm. A No. 1 pressure block is distributed above the No. 1 positioning pin to enable the self-locking nut to engage with the front mounting bracket of the control arm. The workbench is provided with a No. 1 flip cylinder that drives the No. 1 pressure block to flip;

[0008] The No. 2 clamp assembly also includes a No. 5 pressure block that cooperates with the No. 1 limit part to fix the horizontal position of the front mounting bracket of the control arm. The workbench is provided with a No. 1 cylinder that drives the No. 5 pressure block to move in the horizontal direction. The middle part of the No. 5 pressure block is provided with an avoidance groove for avoiding the No. 1 positioning pin.

[0009] The No. 3 clamp assembly includes a No. 2 positioning pin that cooperates with the mounting holes on both sides of the front mounting bracket of the control arm, the No. 2 positioning pin cooperates with the No. 2 cylinder installed on the workbench, the No. 2 positioning pin is hingedly installed at the end of the piston rod of the No. 2 cylinder, the No. 2 positioning pins are each cooperated with a No. 2 pressure block, the No. 2 pressure block cooperates with the No. 3 cylinder installed on the workbench, and the No. 2 pressure block is hingedly installed at the end of the piston rod of the No. 3 cylinder;

[0010] The No. 3 clamp assembly also includes a No. 1 load-bearing portion that fits with the inner surface of the control arm front mounting bracket to support the control arm front mounting bracket. Above the No. 1 load-bearing portion are two No. 3 pressure blocks that are distributed parallel to the length direction of the workbench to press the control arm front mounting bracket assembly and the front subframe. The No. 3 pressure block is connected to the No. 2 flip cylinder installed on the workbench.

[0011] A welding method utilizing an automobile subframe welding system comprises the following steps:

[0012] Step 1: Place the upper and lower pieces of the left and right longitudinal beams on one side of the first welding workstation, and assemble the rear-front connecting plate of the subframe and the inner reinforcement plate of the rear suspension bracket and distribute them on the same side of the upper and lower pieces of the left and right longitudinal beams. Then fix them with a clamping fixture. The left and right longitudinal beams and the rear-front connecting plate assembly of the subframe are welded together by the welding robot and the rotating worktable of the No. 1 positioner.

[0013] Step 2: The turntable rotates, and the rear lower part of the subframe is set in the middle of the other side of the first welding workstation. The rear front connecting plate assembly of the subframe is matched with the rear lower part of the subframe. The front part of the worktable is provided with the left and right front collision bracket lower connecting plates and the rear suspension left bracket. Then, they are fixed with a clamping fixture. The welding robot and the No. 1 positioner rotating worktable are used to weld together to obtain the rear lower part of the subframe assembly.

[0014] Step 3: Use the hoist to lift the left and right longitudinal beam assemblies and the rear lower body of the subframe to the middle of one side of the second welding workstation and combine them. The workbench is also equipped with curved arms on both sides, which are then fixed with clamps. The welding robot and the No. 1 positioner rotate the workbench to weld together to obtain the subframe and the left and right curved arm assemblies.

[0015] Step 4: The welded subframe is lifted with a hoist. The turntable rotates 360 degrees and the hoist places the subframe in the middle of the other side of the second welding workstation. The left and right bending arm assemblies, control arm mounting plates, and front impact bracket plates are then aligned with the subframe and fixed with a clamp. The subframe is then welded together using the welding robot and the No. 1 positioner rotating worktable.

[0016] Step 5: Use the hoist to lift the subframe and transport it to the third welding workstation. Use the hoist to place the subframe in the middle of the workbench on the other side of the third welding workstation. Combine the rear suspension bracket assembly with the subframe and secure them with a clamp. Use the welding robot and the No. 1 positioner to rotate the workbench to perform welding.

[0017] Step 6: Lift the subframe with a hoist, then rotate the turntable 360 degrees and place the subframe on the workbench on one side of the third welding workstation. Fit the left and right front suspension bracket assemblies to the subframe and fix them with a clamp. Use the welding robot and the No. 1 positioner to rotate the workbench to weld and obtain the subframe assembly.

[0018] Step 7: Lift the subframe assembly with a hoist and transport it to the repair welding fixture. Repair welding the subframe assembly is performed by rotating the No. 2 positioner in the repair welding fixture and manual cooperation.

[0019] In the second step, the left and right longitudinal beam upper pieces are set in the workbench, and the longitudinal beam reinforcement plates are matched with the left and right longitudinal beam upper pieces, and then fixed with a clamp. The welding robot and the No. 1 positioner rotate the workbench to perform welding;

[0020] In the second step, the steering gear sleeve is matched with the rear lower piece of the subframe through a clamping fixture. At the same time, the body mounting sleeve is matched with the lower connecting plates of the left and right front collision brackets through a clamping fixture, and then fixed with a clamp. The welding is carried out by the welding robot and the rotating workbench of the No. 1 positioner.

[0021] In the sixth step, the workbench is also equipped with a rear suspension bracket, a rear suspension bracket reinforcement plate and left and right front suspension brackets, which are then fixed with several clamping fixtures and welded together by the welding robot and the No. 1 positioner to rotate the workbench. After welding is completed, the rear suspension bracket assembly is transferred to the workbench in the fifth step for welding to the subframe frame.

[0022] The beneficial effects of the present invention are as follows: the present invention realizes the automated welding and forming of automobile subframes, and performs manual repair welding after welding at the welding workstation to ensure the quality of the final product. At the same time, through the cooperation of the positioner, the turntable and the clamping fixture, the welding of the subframe assembly and the welding of the various subframe components are circulated within the same welding production line, thereby reducing the welding cycle and improving the welding efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention will be further described below with reference to the accompanying drawings and examples.

[0024] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention;

[0025] Figure 2 The first welding workstation of the present invention is a schematic diagram of the three-dimensional structure Figure 1 ;

[0026] Figure 3 The first welding workstation of the present invention is a schematic diagram of the three-dimensional structure Figure 2 ;

[0027] Figure 4 The three-dimensional structure of the second clamp assembly of the present invention is shown as follows Figure 1 ;

[0028] Figure 5 The three-dimensional structure of the second clamp assembly of the present invention is shown as follows Figure 2 ;

[0029] Figure 6 This is a schematic diagram of the three-dimensional structure of the clamp assembly No. 3 of the present invention Figure 1 ;

[0030] Figure 7 The structure of the clamp assembly No. 3 of the present invention is shown in FIG. Figure 2 ;

[0031] Figure 8 This is a schematic diagram of the partial three-dimensional structure of the repair welding tool of the present invention Figure 1 ;

[0032] Figure 9 This is a schematic diagram of the partial three-dimensional structure of the repair welding tool of the present invention Figure 2 ;

[0033] Figure 10 It is a schematic diagram of the three-dimensional structure of the guide assembly of the present invention;

[0034] Figure 11 It is a structural schematic diagram of the lifting mechanism of the present invention;

[0035] Figure 12 It is a schematic diagram of the partial structure of the lifting mechanism of the present invention.

[0036] As shown in the figure: 1. First welding workstation; 2. Second welding workstation; 3. Third welding workstation; 4. Repair welding fixture; 5. Turntable; 6. Positioner No. 1; 7. Workbench; 8. Clamping fixture; 9. Clamp assembly No. 1; 11. Clamp assembly No. 3; 12. Welding robot; 13. Lifting fixture; 101. Locating pin No. 1; 102. Limiting part No. 1; 103. Pressure block No. 1; 104. Turning cylinder No. 1; 105. Pressure block No. 5; 106. Cylinder No. 1; 107. Avoidance groove; 111. Locating pin No. 2; 112. Cylinder No. 2; 113. Pressure block No. 2; 114. Cylinder No. 3; 115. Bearing part No. 1 ;116. Pressure block No. 3;117. Flip cylinder No. 2;118. Mobile platform;119. Cylinder No. 5;41. Frame;42. Positioner No. 2;43. Positioning pin No. 3;44. Bearing part No. 2;45. Guide assembly;46. Lifting mechanism;47. Cylinder No. 4;48. Flip cylinder No. 3;451. Positioning pin No. 4;452. Adapter plate;453. Sleeve;454. Guide rod;455. Spring;461. Lifting platform;462. Connecting column;463. Pressure block No. 4;464. Return spring;465. Limiting groove;467. Guide plate;468. Inclined surface No. 1;469. Inclined surface No. 2. DETAILED DESCRIPTION

[0037] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be explained more clearly and completely below in conjunction with the drawings in the embodiments. Of course, the described embodiments are only a part of the present invention, not all of it. Based on this embodiment, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of the present invention.

[0038] like Figures 1 to 12 As shown, an automobile subframe welding system includes a first welding workstation 1, a second welding workstation 2, a third welding workstation 3, and a repair welding tool 4 arranged in parallel. The first welding workstation 1, the second welding workstation 2, and the third welding workstation 3 are each provided with a turntable 5, on which two sets of No. 1 positioners 6 are provided. The No. 1 positioners 6 are connected to a workbench 7, and the workbench 7 is provided with a clamping fixture 8;

[0039] The turntable 5 is provided with a welding robot 12 cooperating with a corresponding workbench, and the welding workstation is provided with lifting devices 13 for lifting parts.

[0040] The clamping fixture 8 on the workbench 7 on one side of the third welding workstation 3 includes a No. 1 clamp component 9 installed on the workbench 7 and used to fix the front subframe assembly. The workbench 7 is provided with a No. 2 clamp component 10 symmetrically distributed along the length direction of the workbench 7 to fix the left and right front mounting brackets of the control arm. The workbench 7 is also provided with a No. 3 clamp component 11 symmetrically distributed along the length direction of the workbench 7 to enable the left and right front mounting bracket assemblies of the control arm to cooperate with the front subframe assembly.

[0041] The second clamp assembly 10 includes a No. 1 positioning pin 101 that passes through the front mounting bracket of the control arm and is mounted on the workbench 7. The No. 1 positioning pin 101 is matched with a No. 1 limiting portion 102 on the workbench 7 to engage with the front mounting bracket of the control arm to limit the horizontal position of the front mounting bracket of the control arm. A No. 1 pressure block 103 is distributed above the No. 1 positioning pin 101 to enable the self-locking nut to engage with the front mounting bracket of the control arm. A No. 1 turning cylinder 104 is provided on the workbench 7 to drive the No. 1 pressure block 103 to turn over.

[0042] The No. 2 clamp assembly 10 also includes a No. 5 pressure block 105 that cooperates with the No. 1 limiting portion 102 to fix the horizontal position of the control arm front mounting bracket. The workbench 7 is provided with a No. 1 cylinder 106 that drives the No. 5 pressure block 105 to move in the horizontal direction. The middle part of the No. 5 pressure block 105 is provided with an avoidance groove 107 for avoiding the No. 1 positioning pin 101; the No. 2 clamp assembly 10 is used to tighten the control arm front mounting bracket and the self-locking nut and weld them through the welding robot 12 to form a control arm front mounting bracket assembly.

[0043] The No. 1 limiting portion 102 is provided with two along the width direction of the workbench 7, and the No. 5 pressure block 105 is provided corresponding to the No. 1 limiting portion 102. The No. 1 cylinder 106 drives the No. 5 pressure block 105 to cooperate with the No. 1 limiting portion 102 to fix the position of the front mounting bracket of the control arm;

[0044] The self-locking nut cooperates with the No. 1 positioning pin 101 for positioning, and the No. 1 turning cylinder 104 drives the No. 1 pressing block 103 to press the self-locking nut and the front mounting bracket of the control arm.

[0045] The No. 3 clamp assembly 11 includes a No. 2 positioning pin 111 that cooperates with the mounting holes on both sides of the front mounting bracket of the control arm, the No. 2 positioning pin 111 cooperates with a No. 2 cylinder 112 installed on the workbench 7, the No. 2 positioning pin 111 is hingedly installed at the end of the piston rod of the No. 2 cylinder 112, the No. 2 positioning pin 111 is cooperated with a No. 2 pressure block 113, the No. 2 pressure block 113 cooperates with a No. 3 cylinder 114 installed on the workbench 7, and the No. 2 pressure block 113 is hingedly installed at the end of the piston rod of the No. 3 cylinder 114;

[0046] The No. 3 clamp assembly 11 also includes a No. 1 load-bearing portion 115 that fits with the inner surface of the control arm front mounting bracket to support the control arm front mounting bracket. Above the No. 1 load-bearing portion 115, there are two No. 3 pressure blocks 116 distributed parallel to the length direction of the workbench 7 to press the control arm front mounting bracket assembly and the front subframe. The No. 3 pressure block 116 is connected to a No. 2 flip cylinder 117 installed on the workbench 7; a mobile platform 118 is slidably installed on the workbench 7, and the No. 2 flip cylinder 117 and the No. 3 cylinder 114 are both fixed on the mobile platform 118. The workbench 7 is provided with a No. 5 cylinder 119 that drives the mobile platform 118 to slide.

[0047] After placing the control arm front mounting bracket assembly and cooperating with the No. 2 positioning pin 111, the No. 5 cylinder 119 drives the mobile platform 118 to slide so that the control arm front mounting bracket assembly fits into the corresponding position of the front subframe. The No. 2 cylinder 112 drives the No. 2 positioning pin 111 to cooperate with the mounting holes on both sides of the control arm front mounting bracket. Then, the No. 3 cylinder 114 drives the No. 2 pressure block 113 to flip and cooperate with the No. 2 positioning pin 111 to fix the position of the control arm front mounting bracket assembly.

[0048] The No. 2 turning cylinder 117 drives the No. 3 pressing block 116 to turn and press the control arm front mounting bracket assembly and the front subframe, and then the welding robot 12 welds the control arm front mounting bracket assembly to the front subframe.

[0049] The repair welding tool 4 includes a frame 41, and the frame 41 is equipped with a No. 2 positioner 42. The frame 41 is provided with a No. 3 positioning pin 43 that cooperates with the collision bracket assembly in the subframe for positioning and a No. 2 bearing part 44 that cooperates with the control arm mounting point. A guide component 45 is provided below the frame 41, which cooperates with the positioning holes of the lower sheet of the front subframe and the positioning holes of the bent arm to assist the lifting of the subframe. Any one of the No. 3 positioning pin 43 and the No. 2 bearing part 44 is equipped with a No. 3 flip cylinder 48 that presses the subframe.

[0050] The guide assembly 45 includes four positioning pins 451 respectively matched with the positioning holes of the lower plate of the front sub-frame and the positioning holes of the bent arm. The four positioning pins 451 are connected to the adapter plates 452. The adapter plates 452 are connected to the sliding sleeves 453. The sliding sleeves 453 are matched with the guide rods 454 installed at the bottom of the frame 41. A spring 455 is distributed between the sliding sleeves 453 and the guide rods 454. The bottom of the frame 41 is also provided with a lifting mechanism 46 to assist the four positioning pins 451 to rise; the sling 13 lifts the sub-frame as a whole. After being hoisted to the top of the repair welding fixture 4, the sub-frame can be slowly lowered by the guide assembly 45, and the sub-frame can be driven to rise at a uniform speed by the lifting mechanism 46 to prevent the spring 455 from suddenly releasing the elastic force of the No. 3 turning cylinder 48 after it is reset, causing the sub-frame to shake in the repair welding fixture 4 and causing safety accidents such as the sub-frame detachment; at the same time, the existence of the No. 3 turning cylinder 48 will hinder manual operation when the hoist 13 is lowered to retrieve the sub-frame, so the guide assembly 45 is used to lift the sub-frame to reduce the influence of the No. 3 turning cylinder 48 on the sub-frame hoisting.

[0051] The lifting mechanism 46 includes a lifting platform 461, and also includes two connecting columns 462 connected to the sliding sleeve 453 and symmetrically arranged. The lifting platform 461 is provided with a limiting groove 465 that engages with the corresponding connecting column 462. Two No. 4 pressure blocks 463 that fix the corresponding connecting column 462 in the limiting groove 465 are slidably installed on the lifting platform 461. The lifting platform 461 is connected to a No. 4 cylinder 47 installed on the frame 41; after the sub-frame is placed and matched with the No. 4 positioning pin 451, the sliding sleeve 453 slides downward along the guide rod 454 under the action of the gravity of the sub-frame, driving the sub-frame to slowly descend, and at the same time At this time, the connecting column 462 and the first inclined surface 468 engage, driving the fourth pressure block 463 to slide, allowing the connecting column 462 to enter the limit groove 465. The return spring 464 then resets the fourth pressure block 463, pressing the connecting column 462 tightly. After the repair welding is completed, the fourth cylinder 47 drives the lifting platform 461 to rise, which drives the sliding sleeve 453 to rise at a constant speed through the connecting column 462. When the guide wheel 456 cooperates with the second inclined surface 469, it drives the fourth pressure block 463 to move relative to each other. The connecting column 462 is released from the limit groove 465 under the final elastic force of the spring 455. The fourth cylinder 47 then resets the lifting platform 461. The fourth positioning pin 451 is used to lift the subframe to a certain height above the frame 41, preventing the main structure of the repair welding tool 4 from interfering with the lifting and transportation of the subframe, facilitating robot or manual operation.

[0052] A return spring 464 is provided between the fourth pressing block 463, and a guide wheel 456 is provided on each of the fourth pressing blocks 463. The frame 41 is provided with a guide plate 467 that cooperates with the guide wheel 456 to enable the relative movement of the fourth pressing block 463;

[0053] The fourth pressing block 463 is provided with a first inclined surface 468 that abuts against the connecting column 462 , and the guide plate 467 is provided with a second inclined surface 469 that cooperates with the corresponding guide wheel 456 .

[0054] A welding method utilizing an automobile subframe welding system comprises the following steps:

[0055] Step 1: Place the upper and lower pieces of the left and right longitudinal beams on one side of the first welding workstation 1, and assemble the rear-front connecting plate of the subframe and the inner reinforcement plate of the rear suspension bracket and distribute them on the same side of the upper and lower pieces of the left and right longitudinal beams. Then fix them with a clamping fixture 8. The left and right longitudinal beams and the rear-front connecting plate assembly of the subframe are obtained by welding the welding robot 12 and the rotating worktable 7 of the No. 1 positioner 6 in cooperation with each other;

[0056] Step 2: The turntable 5 rotates, and the rear lower plate of the subframe is set in the middle of the other side of the first welding workstation 1, and the rear front connecting plate assembly of the subframe is matched with the rear lower plate of the subframe. The front part of the workbench is provided with the left and right front collision bracket lower connecting plates and the rear suspension left bracket, and then fixed with a clamping fixture 8. The welding robot 12 and the No. 1 positioner 6 rotate the workbench 7 to cooperate with welding to obtain the rear lower plate assembly of the subframe;

[0057] Step 3: Use the hoist 13 to hoist the left and right longitudinal beam assemblies and the rear lower body of the auxiliary frame to the middle of one side of the second welding workstation 2 and combine the left and right longitudinal beam assemblies and the rear lower body of the auxiliary frame. The workbench 7 is also provided with curved arms on both sides, and then fixed with a clamping fixture 8. The welding robot 12 and the No. 1 positioner 6 rotate the workbench 7 to cooperate with welding to obtain the auxiliary frame and the left and right curved arm assemblies;

[0058] Step 4: The welded subframe is lifted by the hoist 13, and the turntable is rotated 360 degrees. The hoist 13 places the subframe in the middle of the other side of the second welding workstation 2. Then, the left and right bending arm assemblies, the control arm mounting plate, and the front collision bracket plate are matched with the subframe and fixed with the clamping fixture 8. The subframe frame is welded together by the welding robot 12 and the rotating worktable 7 of the No. 1 positioner 6;

[0059] Step 5: Lift the subframe by the hoist 13 and transport it to the third welding workstation 3. Place the subframe in the middle of the workbench on the other side of the third welding workstation 3 by the hoist 13. Combine the rear suspension bracket assembly with the subframe and fix them with the clamping fixture 8. Use the welding robot 12 and the No. 1 positioner 6 to rotate the workbench 7 for welding.

[0060] Step 6: Lift the subframe with the lifting device 13, then rotate the turntable 360 degrees to place the subframe on the workbench on one side of the third welding workstation 3, match the left and right front suspension bracket assemblies with the subframe and fix them with the clamping fixture 8, and weld them together with the welding robot 12 and the No. 1 positioner 6 rotating workbench 7 to obtain the subframe assembly;

[0061] Step 7: Lift the sub-frame assembly by the lifting device 13 and transport it to the repair welding fixture 4, where the sub-frame assembly is repair welded by the second positioner 42 in the repair welding fixture 4 and manual cooperation.

[0062] In the second step, the left and right longitudinal beam upper pieces are set in the workbench 7, and the longitudinal beam reinforcement plate is matched with the left and right longitudinal beam upper pieces, and then fixed with a clamping fixture 8. The welding robot 12 and the No. 1 positioner 6 rotate the workbench 7 to cooperate with welding;

[0063] In the second step, the steering gear sleeve is matched with the rear lower plate of the subframe through the clamping fixture 8, and the body mounting sleeve is matched with the lower connecting plates of the left and right front collision brackets through the clamping fixture 8, and then fixed with the clamping fixture 8, and welded by the welding robot 12 and the rotating workbench 7 of the No. 1 positioner 6.

[0064] In the sixth step, the workbench 7 is also provided with a rear suspension bracket, a rear suspension bracket reinforcement plate and the left and right front suspension brackets, which are then fixed with a number of clamping fixtures 8. The welding robot 12 and the No. 1 positioner 6 rotate the workbench 7 to cooperate in welding. After welding is completed, the rear suspension bracket assembly is transferred to the workbench 7 in the fifth step for welding to the subframe frame.

[0065] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and description merely illustrate the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. An automobile subframe welding system, characterized by: The subframe welding system comprises a first welding workstation (1), a second welding workstation (2), a third welding workstation (3), and a repair welding tool (4) arranged in parallel. The subframe welding system also comprises a sling (13). The first welding workstation (1), the second welding workstation (2), and the third welding workstation (3) are each provided with a turntable (5). Two groups of No. 1 positioners (6) are provided on the turntable (5). The No. 1 positioner (6) is connected to a worktable (7). The worktable (7) is provided with a clamping fixture (8). The turntable is provided with a welding robot (12) that cooperates with a corresponding workbench, and the lifting device (13) is capable of lifting parts in the first welding workstation (1), the second welding workstation (2), and the third welding workstation (3); The workbench (7) is also provided with a third clamp assembly (11) symmetrically distributed along the length direction of the workbench (7) to enable the left and right front mounting bracket assemblies of the control arm to cooperate with the front subframe assembly; The No. 3 clamp assembly (11) includes a No. 2 positioning pin (111) matched with the mounting holes on both sides of the front mounting bracket of the control arm, the No. 2 positioning pin (111) is matched with a No. 2 cylinder (112), the No. 2 positioning pin (111) is hingedly mounted on the end of the piston rod of the No. 2 cylinder (112), the No. 2 positioning pin (111) is matched with a No. 2 pressure block (113), the No. 2 pressure block (113) is matched with a No. 3 cylinder (114), and the No. 2 pressure block (113) is hingedly mounted on the end of the piston rod of the No. 3 cylinder (114); The No. 3 clamp assembly (11) also includes a No. 1 bearing portion (115) that is in contact with the inner surface of the control arm front mounting bracket to support the control arm front mounting bracket. Above the No. 1 bearing portion (115), there are two No. 3 pressing blocks (116) distributed parallel to the length direction of the workbench (7) to press the control arm front mounting bracket assembly and the front subframe. The No. 3 pressing block (116) is connected to the No. 2 turning cylinder (117).

2. The automobile subframe welding system according to claim 1, characterized in that: The clamping fixture (8) on the workbench (7) on one side of the third welding workstation (3) includes a No. 1 clamp assembly (9) mounted on the workbench (7) and used to fix the front subframe assembly, and a No. 2 clamp assembly is provided on the workbench (7) and is symmetrically distributed along the length direction of the workbench (7) to fix the left and right front mounting brackets of the control arm.

3. The automobile subframe welding system according to claim 2, characterized in that: The second clamp assembly includes a No. 1 positioning pin (101) that passes through the front mounting bracket of the control arm and is mounted on the workbench (7); the No. 1 positioning pin (101) is matched with a No. 1 limiting portion (102) on the workbench (7) to engage with the front mounting bracket of the control arm to limit the horizontal position of the front mounting bracket of the control arm; a No. 1 pressure block (103) is distributed above the No. 1 positioning pin (101) to enable the self-locking nut to engage with the front mounting bracket of the control arm; and a No. 1 flip cylinder (104) is provided on the workbench (7) to drive the No. 1 pressure block (103) to flip; The No. 2 clamp assembly also includes a No. 5 pressure block (105) that cooperates with the No. 1 limiting portion (102) to fix the horizontal position of the front mounting bracket of the control arm. The workbench (7) is provided with a No. 1 cylinder (106) that drives the No. 5 pressure block (105) to move in the horizontal direction. The middle part of the No. 5 pressure block (105) is provided with an avoidance groove (107) for avoiding the No. 1 positioning pin (101).

4. The automobile subframe welding system according to claim 1, characterized in that: The repair welding fixture (4) includes a frame (41), the frame (41) is equipped with a No. 2 positioner (42), the frame (41) is provided with a No. 3 positioning pin (43) that cooperates with the collision bracket assembly in the subframe for positioning and a No. 2 bearing part (44) that cooperates with the control arm mounting point, and the frame (41) is provided with a guide component (45) below that cooperates with the positioning hole of the lower plate of the front subframe and the positioning hole of the bent arm to assist the subframe in lifting and lowering, and any one of the No. 3 positioning pin (43) and the No. 2 bearing part (44) is equipped with a No. 3 turning cylinder (48) that presses the subframe.

5. The automobile subframe welding system according to claim 4, characterized in that: The guide assembly (45) includes four positioning pins (451) respectively matched with the positioning holes of the lower plate of the front subframe and the positioning holes of the bent arm, the four positioning pins (451) are connected to the adapter plates (452), the adapter plates (452) are connected to the sliding sleeves (453), the sliding sleeves (453) are matched with the guide rods (454) installed at the bottom of the frame (41), and springs (455) are distributed between the sliding sleeves (453) and the guide rods (454). The bottom of the frame (41) is also provided with a lifting mechanism (46) for assisting the four positioning pins (451) to rise.

6. The automobile subframe welding system according to claim 5, characterized in that: The lifting mechanism (46) includes a lifting platform (461), and also includes two connecting columns (462) connected to the sliding sleeve (453) and symmetrically arranged. The lifting platform (461) is provided with a limiting groove (465) engaged with the corresponding connecting column (462). Two No. 4 pressure blocks (463) are slidably installed on the lifting platform (461) to fix the corresponding connecting column (462) in the limiting groove (465). The lifting platform (461) is connected to a No. 4 cylinder (47) installed on the frame (41); A return spring (464) is provided between the fourth pressing blocks (463), a guide wheel (456) is provided on each of the fourth pressing blocks (463), and a guide plate (467) is provided on the frame (41) to cooperate with the guide wheel (456) to enable the fourth pressing block (463) to move relative to each other; The fourth pressing block (463) is provided with a first inclined surface (468) that abuts against the connecting column (462), and the guide plate (467) is provided with a second inclined surface (469) that cooperates with the corresponding guide wheel (456).

7. A welding method using the automobile subframe welding system according to any one of claims 1 to 6, characterized in that: The method comprises the following steps: Step 1: Arrange the upper and lower pieces of the left and right longitudinal beams on one side of the first welding workstation (1), and combine the rear front connecting plate of the subframe and the inner reinforcement plate of the rear suspension bracket and distribute them on the same side of the upper and lower pieces of the left and right longitudinal beams, and then fix them with a clamping fixture (8). The left and right longitudinal beams and the rear front connecting plate assembly of the subframe are obtained by welding the welding robot (12) and the No. 1 positioner (6) rotating workbench (7); Step 2: The turntable (5) is rotated to set the rear lower plate of the sub-frame in the middle of the other side of the first welding workstation (1), and the rear front connecting plate assembly of the sub-frame is matched with the rear lower plate of the sub-frame. The front of the worktable is provided with left and right front collision bracket lower connecting plates and a rear suspension left bracket, and then fixed with a clamping fixture (8). The welding robot (12) and the No. 1 positioner (6) rotate the worktable (7) to cooperate for welding, and the rear lower plate assembly of the sub-frame is obtained; Step 3: The left and right longitudinal beam assemblies and the rear lower plate of the auxiliary frame are hoisted to the middle of one side of the second welding workstation (2) by means of a hoist (13) and the left and right longitudinal beam assemblies and the rear lower plate of the auxiliary frame are combined. The workbench (7) is also provided with curved arms on both sides, which are then fixed with a clamping fixture (8). The welding robot (12) and the No. 1 positioner (6) rotate the workbench (7) to cooperate in welding to obtain the auxiliary frame and the left and right curved arm assemblies; Step 4: The welded sub-frame is lifted by the hoist (13), and the turntable is rotated 360 degrees at the same time. The hoist (13) places the sub-frame in the middle of the other side of the second welding workstation (2). Then, the left and right bending arm assemblies, the control arm mounting plate, and the front collision bracket plate are matched with the sub-frame, and then fixed with a clamping fixture (8). The sub-frame frame is obtained by welding with the welding robot (12) and the No. 1 positioner (6) rotating worktable (7); Step 5: Lift the subframe by the hoist (13) and transport it to the third welding workstation (3), place the subframe in the middle of the workbench on the other side of the third welding workstation (3) by the hoist (13), combine the rear suspension bracket assembly with the subframe, and then fix them with the clamping fixture (8), and weld by the welding robot (12) and the No. 1 positioner (6) to rotate the workbench (7); Step 6: Lift the sub-frame by the lifting device (13), then rotate the turntable 360 degrees to place the sub-frame on the workbench on one side of the third welding workstation (3), match the left and right bracket assemblies of the front suspension with the sub-frame and fix them with the clamping fixture (8), and weld them together by the welding robot (12) and the No. 1 positioner (6) rotating workbench (7) to obtain the sub-frame assembly; Step 7: The sub-frame assembly is lifted by the lifting device (13) and transported to the welding fixture (4), and the sub-frame assembly is repaired by rotating the second positioner (42) in the welding fixture (4) and manually cooperating.

8. The welding method according to claim 7, wherein: In the second step, the workbench (7) is provided with left and right longitudinal beam upper pieces, and the longitudinal beam reinforcement plate is matched with the left and right longitudinal beam upper pieces, and then fixed with a clamping fixture (8), and the workbench (7) is rotated by the welding robot (12) and the No. 1 positioner (6) to perform welding; In the second step, the steering gear sleeve is matched with the rear lower plate of the subframe by the clamping fixture (8), and the body mounting sleeve is matched with the left and right front collision bracket lower connecting plates by the clamping fixture (8), and then fixed with the clamping fixture (8), and the welding is carried out by the welding robot (12) and the No. 1 positioner (6) rotating workbench (7).

9. The welding method according to claim 7, wherein: In the sixth step, a rear suspension bracket, a rear suspension bracket reinforcement plate, and left and right front suspension brackets are also provided on the workbench (7), which are then fixed with a plurality of clamping fixtures (8). The welding robot (12) and the No. 1 positioner (6) rotate the workbench (7) to cooperate with welding; after the welding is completed, the rear suspension bracket assembly is transferred to the workbench (7) in the fifth step for welding with the subframe frame.

Images