An automatic welding system for automobile rear longitudinal beam

Abstract

The present invention relates to the technical field of automobile sheet metal welding, and specifically proposes an automatic welding system for automobile rear longitudinal beams; the system is used for aligning and positioning the longitudinal beam front section and the longitudinal beam rear section in the rear longitudinal beam main beam of the automobile; the system comprises a welding fixture for welding and positioning the rear longitudinal beam main beam and a welding actuator for welding in cooperation with the welding fixture; the welding fixture comprises a fixture table, two fixture assemblies and two cleaning assemblies, and the fixture table is equipped with a lifting platform; the two fixture assemblies are respectively used for clamping and positioning the longitudinal beam front section and the longitudinal beam rear section, the two fixture assemblies and the two cleaning assemblies are respectively fixed on the fixture table surface and the lifting platform surface, and the two cleaning assemblies are arranged in a one-to-one correspondence with the two fixture assemblies; the welding system provided by the present invention improves the welding efficiency and ensures the welding quality through the improved design of the welding fixture and the matching and integrated design with the relevant cleaning structure.

Description

Technical Field

[0001] The invention relates to the technical field of automobile sheet metal welding, and specifically proposes an automatic welding system for an automobile rear longitudinal beam. Background Art

[0002] The rear longitudinal beam of a car is an important part of the vehicle chassis structure. It is located at the rear of the car body and extends longitudinally along both sides of the car body. The rear longitudinal beam plays a supporting and reinforcing role in the car structure, and plays an important role in ensuring the overall rigidity and safety of the car body. The longitudinal beam of a car is usually composed of a main beam and accessories. The main beam is generally composed of two or more main beam sections. The main beam and accessories need to be assembled and formed by welding; the welding process of the longitudinal beam of a car is usually a complex and multi-level process, which aims to ensure the strength, rigidity and precision of the final component. In general, multiple main beam sections are preliminarily welded to form the basic longitudinal beam structure, and then the accessories such as the support plate and the reinforcement plate are welded. The use of sequential segmented welding is not only conducive to improving production efficiency and controlling welding deformation, but also helps to ensure the overall stability and welding quality of the structure.

[0003] The present invention provides an automatic welding system for a rear longitudinal beam of an automobile, which is mainly used for butt welding of a longitudinal beam main beam including two main beam sections. In the existing welding production process, a matching welding fixture is used to weld and position the longitudinal beam main beam, but the existing welding fixture basically adopts a one-step clamping and positioning design, that is, the positioning and butt joint between the main beam sections is directly completed in one step, and the longitudinal beam main beam is a sheet metal part with limited material thickness, and it is inevitably subject to external forces such as collision and extrusion during storage and transportation, which may cause certain deformation of the main beam section, especially when the welding overlap section of the main beam section is deformed, and the overlap surfaces of the two main beam sections are closely matched, the material deformation increases the probability of overlap interference, and reduces the accuracy of overlap matching, so the existing one-step clamping and positioning design structure increases the difficulty of the clamping and positioning operation, and there is a problem of large positioning error.

[0004] In addition, during the storage and transportation of the main beam section, its surface may be oxidized to form an oxide layer, and impurities such as oil, dust particles and so on will inevitably adhere to it. Before welding, it is of great significance to clean the lap joint of the main beam section. In actual operation, it is usually necessary to manually clean the welded lap joint before welding. When the impurity layer is thick and some impurities are highly viscous, manual cleaning becomes more difficult, and manual cleaning may result in problems such as inadequate cleaning or partial omissions. When the impurity layer is not obvious, cleaning may be directly ignored. However, the presence of any degree of impurities at the welded lap joint may cause quality defects such as pores, slag inclusions and low welding strength at the joints after welding. Summary of the invention

[0005] In order to solve the above problems, the present invention provides an automatic welding system for a rear longitudinal beam of an automobile, which is used to solve the problems mentioned in the above background technology.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme to achieve: an automatic welding system for automobile rear longitudinal beams, which is used for aligning and positioning the longitudinal beam front section and the longitudinal beam rear section in the rear longitudinal beam main beam of the automobile; it includes a welding fixture for welding and positioning the rear longitudinal beam main beam and a welding actuator for welding in cooperation with the welding fixture; the welding fixture includes: a fixture table, on which a lifting platform is installed; two fixture assemblies, which are respectively used to clamp and position the longitudinal beam front section and the longitudinal beam rear section, one fixture assembly is installed on the fixture table surface, and the other fixture assembly is installed on the lifting platform surface; the fixture assembly includes a translation base horizontally slidably installed on the table surface, and a downward pressure component and a plurality of supporting side clamping components are fixed on the translation base, and the horizontal side clamps of the longitudinal beam front section or the longitudinal beam rear section are placed on the plurality of supporting side clamping components and are pressed by the downward pressure component; and two cleaning assemblies, which are respectively fixed on the fixture table surface and the lifting platform surface, and are arranged in a one-to-one correspondence with the two fixture assemblies.

[0007] After the front section and the rear section of the longitudinal beam are positioned and clamped by the clamp assembly, when the translation bases drive the front section and the rear section of the longitudinal beam to move relatively close to each other, the two cleaning assemblies respectively clean the welding lap surfaces of the front section and the rear section of the longitudinal beam simultaneously; when and only when the front section and the rear section of the longitudinal beam are translated until their welding lap surfaces are vertically aligned, the lifting platform descends, so that the welding lap surfaces of the front section and the rear section of the longitudinal beam are completed to be fitted and connected up and down.

[0008] Preferably, the cleaning assembly includes: a support frame; a cleaning component, which is slidably installed on the support frame along the sliding direction of the translation base, and when the translation base drives the front section or the rear section of the longitudinal beam to translate through the cleaning component, the cleaning component cleans the welding lap surface of the front section or the rear section of the longitudinal beam; and a lateral swing component, which is fixed on the support frame and is used to drive the cleaning component to swing back and forth in the moving direction of the translation base to achieve reciprocating swing cleaning.

[0009] Preferably, the cleaning component includes: a sliding frame, which is slidably mounted on a supporting frame along the translation direction of the translation base; an air box, which is fixed on the sliding frame and can allow gas to enter and exhaust, and the air box is provided with an exhaust surface that faces the lap surface of the front section of the longitudinal beam or the rear section of the longitudinal beam and has a contour that is adapted, and air holes are evenly opened on the exhaust surface; and a cleaning brush, which can be removably covered and fixed on the exhaust surface of the air box, and the gas exhausted from the air box is discharged outward from the brush layer of the cleaning brush.

[0010] Preferably, an air pipe for inward ventilation is connected and fixed on the air box; the sway assembly includes: a driven block horizontally fixed on the end of the air pipe, the driven block is provided with an extension hole extending horizontally and perpendicular to the sliding direction of the sliding frame; a driving motor vertically fixed on the support frame; and a driving disk fixed on the output shaft of the driving motor, an eccentric pin is fixed at a non-center position on the driving disk, and the eccentric pin is inserted in the extension hole.

[0011] Preferably, the supporting side clamp component includes: a supporting frame for horizontally supporting the front section or the rear section of the longitudinal beam; and a side clamp assembly assembled on the supporting frame for clamping the outer side walls of the front section or the rear section of the longitudinal beam on both sides.

[0012] Preferably, the pressing component includes: a guide frame; a driving assembly, which is assembled on the guide frame; and a pressing piece, which is assembled on the driving assembly and is used to press down and contact the front section or the rear section of the longitudinal beam; under the cooperation and guidance of the guide frame, the driving assembly drives the pressing piece to move downward and press on the front section or the rear section of the longitudinal beam, and drives the pressing piece to move away from the front section or the rear section of the longitudinal beam.

[0013] Preferably, the support frame includes: two side brackets; and a support plate, which is used to horizontally support the front section or the rear section of the longitudinal beam and is horizontally fixed between the two side brackets, and the support plate is fixed with a positioning pin that is inserted into the fixing hole in the front section or the rear section of the longitudinal beam.

[0014] Preferably, the side clamp assembly comprises two side clamp blocks which are mounted on two side brackets in a one-to-one correspondence and are relatively horizontally slidable, and the side clamp blocks are in flexible clamping contact with the front section of the longitudinal beam or the rear section of the longitudinal beam.

[0015] Preferably, the guide frame includes at least one side plate, a track hole is formed on the side plate, and the track hole includes an inclined section and a vertical section from top to bottom; the driving assembly includes: a driving slider, which is provided with a lifting drive and is vertically slidably mounted on the side plate; a pressure plate, which is horizontally slidably mounted on the driving slider; and a moving pin, which is fixed on the pressure plate and moves along the track hole, and the lower pressure piece is fixed at the bottom end of the pressure plate; during the descending process of the driving slider, when the moving pin moves along the inclined section of the track hole, the lower pressure piece descends together with the pressure plate and moves horizontally toward and directly above the pressed surface of the front section of the longitudinal beam or the rear section of the longitudinal beam.

[0016] Preferably, the pressing member is a plurality of pressing rods vertically fixed at the bottom end of the pressing member plate, and the lower ends of the pressing rods are in flexible pressing contact with the front section of the longitudinal beam or the rear section of the longitudinal beam.

[0017] The above technical scheme has the following advantages or beneficial effects: the present invention provides an automatic welding system for automobile rear longitudinal beams, and provides a welding fixture for butt-jointing the front section and the rear section of the longitudinal beam of the main beam of the automobile rear longitudinal beam, which changes the structural design and clamping positioning method of the existing welding fixture which adopts an integrated one-time clamping and positioning, and adopts a structural design and clamping positioning method which performs preliminary independent clamping and positioning, horizontal translation alignment, and vertical descent and embedding butt joint on the front section and the rear section of the longitudinal beam, which can complete preliminary clamping and positioning as well as adaptive positioning and adjustment butt joint, and improves the accuracy and flexibility of clamping, positioning and butt joint. It is active and convenient for actual operation. In addition, a cleaning assembly is assembled corresponding to the front section and the rear section of the longitudinal beam, and the welding overlap surface areas of the front section and the rear section of the longitudinal beam are automatically covered and cleaned by using the horizontal translation alignment process, which ensures the cleaning effect while avoiding the trouble of manual cleaning of the welding surface before welding, and solves the welding quality defects caused by omitting or forgetting to clean the welding surface. In summary, the welding system provided by the present invention improves the welding efficiency and ensures the welding quality through the improved design of the welding fixture and the supporting integrated design with the relevant cleaning structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention and its features, configurations and advantages will become more apparent by reading the detailed description of non-limiting embodiments with reference to the following drawings. The same reference numerals indicate the same parts throughout the drawings, which are not drawn to scale, with emphasis on illustrating the subject matter of the present invention.

[0019] Figure 1 The present invention is a schematic diagram of the three-dimensional structure of an automatic welding system for a rear longitudinal beam of an automobile.

[0020] Figure 2 It is a three-dimensional structural schematic diagram of the fixture assembly.

[0021] Figure 3 It is a three-dimensional structural schematic diagram of a cleaning assembly used to clean the welding overlap surface of the front section of the longitudinal beam.

[0022] Figure 4 It is a three-dimensional structural schematic diagram of a cleaning assembly used to clean the welding overlap surface of the rear section of the longitudinal beam.

[0023] Figure 5 yes Figure 3 A stereoscopic view of the assembly of the air box, cleaning brush and driven block in the cleaning assembly shown.

[0024] Figure 6 yes Figure 4 A stereoscopic view of the assembly of the air box, cleaning brush and driven block in the cleaning assembly shown.

[0025] Figure 7It is a three-dimensional structural diagram of the rear longitudinal beam and main beam of an automobile after welding.

[0026] Figure 8 It is a three-dimensional structural diagram of the front section of the longitudinal beam.

[0027] Fig. 9 This is a three-dimensional structural diagram of the rear section of the longitudinal beam.

[0028] Fig.10 The present invention is a schematic diagram of the three-dimensional processing state of an automatic welding system for a rear longitudinal beam of an automobile provided by the present invention.

[0029] Fig.11 yes Fig.10 Front view of the machined state shown.

[0030] In the figure: 1, fixture table; 11, lifting platform; 111, lifting base; 112, lifting cylinder; 113, guide column; 12, guide rail base.

[0031] 2. Shift the base horizontally.

[0032] 3. Supporting side clamp components; 31. Supporting bracket; 311. Side bracket; 312. Supporting plate; 313. Positioning pin; 32. Side clamp assembly; 321. Side clamp cylinder; 322. Connecting rod; 323. Guide rod; 324. Side clamp block.

[0033] 4. Pressing component; 41. Guide frame; 411. Side plate; 412. Slide rail; 413. Track hole; 42. Driving assembly; 421. Driving cylinder; 422. Driving slider; 423. Pressing plate; 424. Moving pin; 43. Pressing rod.

[0034] 5. Cleaning assembly; 51. Support frame; 52. Cleaning parts; 521. Sliding frame; 522. Air box; 5221. Air pipe; 523. Cleaning brush; 5231. Base layer; 5232. Brush layer; 53. Swing assembly; 531. Drive motor; 532. Drive disk; 533. Eccentric pin; 534. Follower block.

[0035] 6. Main beam of rear longitudinal beam; 61. Front section of longitudinal beam; 62. Rear section of longitudinal beam. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] In order to enable those skilled in the art to better understand the scheme of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0038] An automatic welding system for rear longitudinal beams of automobiles is used for Figure 7 The longitudinal beam front section 61 ( Figure 8 ) and the rear section of the longitudinal beam 62 ( Fig. 9 ) for alignment and positioning welding, Figure 7 In the figure, the left side is the longitudinal beam front section 61, and the right side is the longitudinal beam rear section 62. During welding, the left end outer wall of the longitudinal beam rear section 62 is embedded and overlapped on the right end inner wall of the longitudinal beam front section 61, and overlap welding is achieved through the overlap surfaces of the two.

[0039] like Figure 1 As shown, the welding system includes a welding fixture for welding and positioning the rear longitudinal beam main beam 6 and a welding actuator for welding in cooperation with the welding fixture; in this embodiment, the welding actuator is an existing welding robot arm, and when the rear longitudinal beam main beam 6 is clamped and positioned by the welding fixture, automatic welding is performed by the welding actuator. It should be noted that the welding actuator is not shown in the accompanying drawings.

[0040] like Figure 1 , Fig.10 and Fig.11 As shown, the welding fixture includes a fixture table 1, a guide rail base 12 is welded on the table top of the fixture table 1, and a lifting platform 11 is also installed on the fixture table 1; the lifting platform 11 includes a lifting base 111 horizontally arranged above the table top of the fixture table 1 and a lifting cylinder 112 vertically fixed to the bottom end of the table top of the fixture table 1 by bolts, the lifting base 111 is fixed to the output end of the lifting cylinder 112 by bolts, four guide columns 113 are fixed to the bottom end of the lifting base 111 by screws, and the guide columns 113 are vertically slidably installed on the lifting platform 11; in this embodiment, horizontal guide rails are welded on the lifting base 111 and the guide rail base 12, and the two horizontal guide rails are arranged in parallel.

[0041] like Figure 2 and Fig.11As shown, the lifting base 111 and the guide rail base 12 are respectively equipped with a clamp assembly, and the two clamp assemblies are used to clamp and position the longitudinal beam front section 61 and the longitudinal beam rear section 62 respectively; the clamp assembly includes a translation base 2, the clamp assembly assembled on the lifting base 111 is mounted on the horizontal guide rail on the lifting base 111 through the translation base 2 horizontal sliding cooperation, and the clamp assembly assembled on the guide rail base 12 is mounted on the horizontal guide rail on the guide rail base 12 through the translation base 2 horizontal sliding cooperation, and the lifting base 111 and the guide rail base 12 can be horizontally fixed with a cylinder, and the cylinder is used to drive the translation base 2 at their respective positions to move; the translation base 2 is fixed with a downward pressing component 4 and two supporting side clamp components 3. It should be noted that the two clamp assemblies have the same structural composition and the same function, but need to be matched with the longitudinal beam front section 61 and the longitudinal beam rear section 62 respectively, so there are size differences between some parts, which are not distinguished here.

[0042] like Figure 2 As shown, the supporting side clamp component 3 includes a supporting bracket 31 and a side clamp assembly 32 assembled on the supporting bracket 31. The supporting bracket 31 includes two side brackets 311 fixed to the translation base 2 by bolts and a supporting plate 312 horizontally welded between the two side brackets 311. The supporting plate 312 is used to horizontally support the front section 61 of the longitudinal beam or the rear section 62 of the longitudinal beam. In order to facilitate rapid and accurate positioning, a positioning pin 313 is vertically welded on the upper end surface of the supporting plate 312 to cooperate with the fixing hole in the front section 61 of the longitudinal beam or the rear section 62 of the longitudinal beam. The fixing holes here generally refer to bolt holes or structural holes for other purposes opened in the front section 61 of the longitudinal beam and the rear section 62 of the longitudinal beam, or positioning holes specially opened to cooperate with the positioning of the fixture. The side clamp assembly 32 is used to clamp the outer side walls of the longitudinal beam front section 61 or the longitudinal beam rear section 62 on both sides. The side clamp assembly 32 includes a side clamp cylinder 321 vertically fixed on the translation base 2. The side clamp cylinder 321 is centrally located below the support plate 312. The output end of the side clamp cylinder 321 is hinged to two connecting rods 322 through a hinge joint. The other ends of the two connecting rods 322 are hinged to side clamp blocks 324. The side walls of the two side brackets 311 facing away from the support plate 312 are horizontally welded with guide Rod 323, guide rod 323 is arranged perpendicularly in the axial direction relative to the moving direction of translation base 2, two side clamping blocks 324 are slidably installed on two guide rods 323 in one-to-one correspondence, and side clamping blocks 324 and guide rods 323 are key-matched; the clamping ends of side clamping blocks 324 and outer side walls of longitudinal beam front section 61 or longitudinal beam rear section 62 are multiple rubber blocks, which realize flexible clamping contact instead of rigid clamping, avoid indentation, and facilitate adaptive relative fine-tuning when longitudinal beam front section 61 and longitudinal beam rear section 62 are docked.

[0043] like Figure 2As shown, the pressing component 4 is located on one side of the two supporting side clamping components 3 and is relatively centrally arranged; the pressing component 4 includes a guide frame 41, a driving assembly 42 and a pressing member driven by the driving assembly 42; the guiding frame 41 includes two side plates 411 vertically welded on the translation base 2 and a baffle plate welded between the two side plates 411; vertically guided slide rails 412 are welded on the opposite surfaces of the two side plates 411, and both are provided with track holes 413, and the track holes 413 include an inclined section and a vertical section from top to bottom (specifically, see Figure 2 ); The driving assembly 42 includes a driving cylinder 421, a driving slider 422 and a pressure plate 423. The driving cylinder 421 is vertically fixed on the baffle. The driving slider 422 is horizontally fixed to the output end of the driving cylinder 421 by screws and is vertically slidably installed between the two slide rails 412. The pressure plate 423 is horizontally slidably installed on the driving slider 422. The sliding directions of the pressure plate 423 and the translation base 2 are relatively vertically arranged. A moving pin 424 is horizontally fixed to the top of the pressure plate 423. The moving pin The two ends of 424 are correspondingly inserted into the track holes 413 of the two side plates 411, and the moving pin 424 moves along the track hole 413; in this embodiment, in order to disperse the pressure, the lower pressing piece is specifically three lower pressing rods 43 vertically welded to the bottom end of the pressing piece plate 423, and the three lower pressing rods 43 are evenly distributed along the axis of the moving pin 424. The lower end of the lower pressing rod 43 is sleeved with a rubber sleeve to achieve flexible pressing contact with the front section 61 of the longitudinal beam or the rear section 62 of the longitudinal beam. Similarly, it can avoid the generation of indentations and facilitate adaptive adjustment of the alignment. Under the guidance of the guide frame 41, the driving component 42 drives the lower pressing piece to move down and press on the front section 61 of the longitudinal beam or the rear section 62 of the longitudinal beam, and drives the lower pressing piece to move away from the front section 61 of the longitudinal beam or the rear section 62 of the longitudinal beam.

[0044] Before welding, the longitudinal beam front section 61 and the longitudinal beam rear section 62 need to be clamped and fixed respectively by two clamp assemblies. Before positioning, the two translation bases 2 are at the maximum distance from each other, and the lifting base 111 is at the highest position. During the positioning operation, the longitudinal beam front section 61 can be clamped and positioned first, regardless of the order, that is, the longitudinal beam front section 61 is clamped and positioned and placed at the Fig.11 In the left fixture assembly, specifically, firstly straighten the front section 61 of the longitudinal beam so that the lap joint end is at Fig.11 The longitudinal beam front section 61 is then placed on the two supporting plates 312 , and the positioning pins 313 on the two supporting plates 312 are inserted into the two fixing holes of the longitudinal beam front section 61 in a one-to-one correspondence.

[0045] Since the outer walls of both sides of the longitudinal beam front section 61 have an outward angle (the angle between the outer wall of the longitudinal beam front section 61 and the horizontal end face of the inner wall is greater than 90 degrees), the side clamping block 324 first clamps the side wall to generate an upward thrust, which may cause the longitudinal beam front section 61 to be lifted upward and separated from the supporting plate 312. Therefore, when the longitudinal beam front section 61 is placed horizontally, the longitudinal beam front section 61 can be first clamped by the pressing component 4. Specifically, the driving cylinder 421 is started to drive the driving slider 422 to slide down along the two slide rails 412, and the driving slider 422 drives the pressing plate 423 to move along the track hole 413 through the track pin. When the track When the pin moves along the inclined end of the track hole 413, the push-down rod 43 continues to descend and gradually moves toward the top of the structural groove of the front section 61 of the longitudinal beam (the structural groove refers to the feature that the front section 61 of the longitudinal beam is a groove plate structure as a whole). When the track pin moves to the turning position of the inclined section and the vertical section in the track hole 413, the push-down rod 43 just moves to the top of the structural groove of the front section 61 of the longitudinal beam. Subsequently, the driving slider 422 continues to slide down, and the track pin continues to move along the vertical section of the track hole 413, eventually causing the three push-down rods 43 to move down and press against the horizontal surface of the inner wall of the groove of the front section 61 of the longitudinal beam, thereby completing the downward positioning.

[0046] Subsequently, the side clamp cylinder 321 is started, and the side clamp block 324 is driven by the connecting rod 322 to clamp the side wall of the front section 61 of the longitudinal beam, so that the front section 61 of the longitudinal beam is finally placed on the two supporting side clamp parts 3 by the supporting side clamps, and is moved downward and clamped under the pressing part 4; since the pressing part 4 is basically in a centralized position relative to the two supporting side clamp parts 3, the three positioning positions roughly form an isosceles triangle structure, which achieves stable clamping in mechanics.

[0047] The rear section 62 of the longitudinal beam can then be positioned and clamped. The operation process of clamping the rear section 62 of the longitudinal beam by the clamp assembly is basically the same as the clamping operation process of the front section 61 of the longitudinal beam, and will not be repeated here.

[0048] Cleaning assemblies 5 are correspondingly installed on the lifting base 111 and the guide rail base 12, and are arranged in a one-to-one correspondence with the two clamp assemblies; one cleaning assembly 5 is used to automatically clean the inner wall lap joint surface of the front section 61 of the longitudinal beam, and the other cleaning assembly 5 is used to automatically clean the outer wall lap joint surface of the rear section 62 of the longitudinal beam. It should be noted that the structural compositions of the two cleaning assemblies 5 correspond, but the corresponding cleaning positions are different. Therefore, there are differences in size and appearance between the corresponding components in the two cleaning assemblies 5. In order to simplify the expression, based on the corresponding structural composition and the same function, the two cleaning assemblies 5 are not distinguished by marking.

[0049] like Figure 3 , Figure 4 , Figure 5 , Figure 6 and Fig.10As shown, the cleaning assembly 5 includes a support frame 51 welded on the translation base 2, a cleaning component 52 mounted on the support frame 51, and a swaying assembly 53 driving the cleaning component 52; the cleaning component 52 includes two sliding frames 521 slidably mounted on the support frame 51 along the translation direction of the translation base 2, and an air box 522 is welded between the two sliding frames 521. The air box 522 is a box structure, and an air pipe 5221 for inward ventilation is welded on the air box 522. The air pipe 522 is welded to the air box 522. The outlet of the air pipe 5221 is opened on the side wall, and the outlet of the air pipe 5221 can be connected to a hose for introducing pressurized air. The air box 522 is provided with an exhaust surface facing the overlap surface of the longitudinal beam front section 61 or the longitudinal beam rear section 62 and having a contour adapted thereto. The exhaust surface of the air box 522 is similar to a U-shaped surface, and air holes are evenly opened on the exhaust surface. A cleaning brush 523 is detachably covered and fixed on the exhaust surface of the air box 522, and the cleaning brush 523 includes a base layer 5231 made of silicone and an embedded woven The brush layer 5232 on the base layer 5231 completely covers the exhaust surface, and the edge of the base layer 5231 is fixed to the exhaust surface of the air box 522 by glue. The base layer 5231 is also provided with air holes, and the distribution positions of the air holes basically correspond to the distribution positions of the air holes on the exhaust surface of the air box 522. In this embodiment, the bristles of the brush layer 5232 are made of hard nylon material, and the pressurized air discharged through the air box 522 can be discharged outwardly from the gaps between the bristles of the brush layer 5232; in addition, it should be added that in order to facilitate more thorough cleaning of oil stains, oxide layers and firmly bonded dust that may exist on the overlapping surface, a flexible grinding strip that can form an effective fit with the overlapping surface is also centrally embedded in the brush layer 5232, and the supporting layer of the flexible grinding strip can be integrally formed with the base layer 5231, and the grinding layer of the flexible grinding strip can adopt cloth-based sandpaper, which can be attached to the supporting layer on the base layer 5231 and can be replaced. The sway assembly 53 includes a driven block 534 horizontally welded to the end of the air pipe 5221, and an extension hole extending horizontally and perpendicularly to the sliding direction of the sliding frame 521 is opened on the driven block 534; a driving motor 531 is vertically fixed to the support frame 51 by screws, and a driving disk 532 is fixed to the output shaft of the driving motor 531 by screws, and an eccentric pin 533 is welded at a non-center position on the driving disk 532, and the eccentric pin 533 is inserted in the extension hole; when the driving motor 531 is started, the driving disk 532 rotates, and the eccentric pin 533 is used to move the driven block 534, so that the cleaning component 52 as a whole moves back and forth on the support frame 51.

[0050] It should be particularly pointed out that in the cleaning assembly 5, the support frame 51 is a frame structure with a lifting function, that is, the horizontal end of the support frame 51 can be independently lifted and lowered, and the lifting structure design is an existing conventional design, so the specific lifting structure features of the support frame 51 are not specifically shown in the drawings; the support frame 51 with a lifting function, on the one hand, can adjust the fit strength between the cleaning brush 523 and the lap end of the longitudinal beam front section 61 or the longitudinal beam rear section 62 through the lifting function, and on the other hand, after the welding is completed, the cleaning brush 523 can be adjusted to fit the lap end of the longitudinal beam front section 61 or the longitudinal beam rear section 62. Fig.11 The cleaning component 52 in the middle left cleaning assembly 5 is moved upward from the longitudinal beam front section 61, thereby avoiding the longitudinal beam front section 61, so as to facilitate the removal of the welded rear longitudinal beam main beam 6 from the welding fixture.

[0051] After the longitudinal beam front section 61 and the longitudinal beam rear section 62 are positioned and clamped respectively, the welded overlap surfaces of the two can be butted. Specifically, the driving motors 531 of the two cleaning assemblies 5 are first started to put the cleaning assemblies 5 in a working state. Subsequently, the longitudinal beam front section 61 and the longitudinal beam rear section 62 are respectively driven to move by the two translation bases 2, so that the longitudinal beam front section 61 and the longitudinal beam rear section 62 move toward each other. Fig.11 As shown in the perspective, during translation, the front section 61 of the longitudinal beam moves from left to right, and the cleaning component 52 of the cleaning assembly 5 on the left side will move relatively into the structural groove of the front section 61 of the longitudinal beam, and clean the overlapping surface of the inner wall of the front section 61 of the longitudinal beam. The rear section 62 of the longitudinal beam moves from right to left, and the overlapping surface of the outer wall of the front section 61 of the longitudinal beam will pass through the groove of the cleaning brush 523 of the right cleaning assembly 5, and the cleaning brush 523 will perform a wrap-up cleaning on the overlapping surface of the outer wall of the rear section 62 of the longitudinal beam. The cleaning assembly 5 grinds and cleans the overlapping surface of the front section 61 of the longitudinal beam or the rear section 62 of the longitudinal beam through the reciprocating movement of the cleaning component 52, thereby cleaning impurities such as oil stains, oxide layers, and adhered dust particles that may exist on the overlapping surface, and the pressurized air discharged synchronously from the cleaning component 52 can blow away the cleaned impurities.

[0052] Before translation, the two clamp assemblies are far apart, so that the independent clamping and positioning of the longitudinal beam front section 61 and the longitudinal beam rear section 62 can be easily completed, and the initial positioning before overlapping can be realized. During the translation and docking process, the overlapping surfaces of the longitudinal beam front section 61 and the longitudinal beam rear section 62 can be synchronously and automatically cleaned, avoiding the trouble of manual cleaning of the welding surface before welding, and also avoiding the welding quality defects that may be caused by omitting or forgetting cleaning. At the same time, the full integration of the operation process is realized, and the efficient use of time is improved.

[0053] As the translation base 2 continues to translate, when the two translation bases 2 move relatively to the closest position, they stop, and the outer wall overlap surface of the longitudinal beam rear section 62 will move relatively to just above the inner wall overlap surface of the longitudinal beam front section 61, and be at a predetermined overlap length position, then the lifting platform 11 descends, and drives the longitudinal beam rear section 62 to descend accordingly, and then the overlap section of the longitudinal beam rear section 62 descends into the groove of the longitudinal beam front section 61, so that the welded overlap surfaces of the longitudinal beam front section 61 and the longitudinal beam rear section 62 are completed. Fitting and docking; in this embodiment, the upper and lower relative displacement overlap method is adopted. On the one hand, since the front section 61 and the rear section 62 of the longitudinal beam are both grooved plate structures, and the cross-sections of both are approximately trapezoidal cross-sectional profiles, and the outer walls have an outward angle, it is convenient to carry out upper and lower embedded docking. On the other hand, the difficulty of the docking operation is reduced during the upper and lower offset embedded docking process. On the basis of each independently positioning and clamping to complete the initial positioning, the front section 61 and the rear section 62 of the longitudinal beam can form an adaptive positioning adjustment of the overlapping matching positioning position with each other, and the deformation position of the overlapping section on the front section 61 or the rear section 62 of the longitudinal beam can be self-corrected to a certain extent.

[0054] After the longitudinal beam front section 61 and the longitudinal beam rear section 62 are butt-jointed and positioned, the welding actuator can be used for automatic welding. After the welding is completed, the two clamp assemblies are released and the Fig.11 The cleaning component 52 of the left cleaning assembly 5 is lifted up and moved out from the groove of the longitudinal beam front section 61, and then the welded rear longitudinal beam main beam 6 is lifted up and moved out horizontally.

[0055] The present invention provides an automatic welding system for a rear longitudinal beam of an automobile, and provides a welding fixture for butt-jointing a longitudinal beam front section 61 and a longitudinal beam rear section 62 of a rear longitudinal beam main beam 6 of an automobile. The present invention changes the structural design and clamping positioning method of the existing welding fixture which adopts an integrated one-time clamping positioning, and adopts a structural design and clamping positioning method which performs preliminary independent clamping positioning, horizontal translation alignment, and vertical descending embedding butt jointing on the longitudinal beam front section 61 and the longitudinal beam rear section 62. The preliminary clamping positioning and adaptive positioning and adjustment butt jointing can be completed, thereby improving the accuracy and flexibility of clamping, positioning, and butt jointing, and facilitating actual operation. In addition, a cleaning assembly 5 is correspondingly assembled with the longitudinal beam front section 61 and the longitudinal beam rear section 62, and the welding overlap surface area of ​​the longitudinal beam front section 61 and the longitudinal beam rear section 62 is automatically covered and cleaned by using the horizontal translation alignment process, thereby ensuring the cleaning effect while avoiding the trouble of manually cleaning the welding surface before welding, and also solving the welding quality defects caused by omitting or forgetting to clean the welding surface; in summary, the welding system provided by the present invention improves the welding efficiency while ensuring the welding quality through the improved design of the welding fixture and the integrated design with the relevant cleaning structure.

[0056] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0057] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "connect", "install", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0058] The above describes the preferred embodiments of the present invention. It should be understood that the present invention is not limited to the above-mentioned specific embodiments, and the devices and structures that are not described in detail should be understood to be implemented in a common manner in the art; any technician familiar with the art can make many possible changes and modifications without departing from the technical solution of the present invention, or modify them into equivalent embodiments with equivalent changes, which does not affect the essential content of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of protection of the technical solution of the present invention.

Claims

1. An automatic welding system for a rear longitudinal beam of an automobile, used for aligning and positioning welding a longitudinal beam front section (61) and a longitudinal beam rear section (62) in a rear longitudinal beam main beam (6) of an automobile; characterized in that: It comprises a welding fixture for welding and positioning the rear longitudinal beam main beam (6) and a welding execution part that cooperates with the welding fixture for welding; The welding fixture comprises: A fixture table (1), wherein a lifting platform (11) is mounted on the fixture table (1); Two clamp assemblies are used to clamp and position the front section (61) of the longitudinal beam and the rear section (62) of the longitudinal beam respectively. One clamp assembly is mounted on the surface of the clamp table (1), and the other clamp assembly is mounted on the surface of the lifting platform (11). The clamp assembly includes a translation base (2) mounted on the surface in a horizontally sliding manner. A downward pressing component (4) and a plurality of supporting side clamping components (3) are fixed on the translation base (2). The horizontal side clamps of the front section (61) of the longitudinal beam or the rear section (62) of the longitudinal beam are placed on the plurality of supporting side clamping components (3) and are pressed by the downward pressing component (4). and two cleaning assemblies (5), which are respectively fixed on the table top of the fixture table (1) and the table top of the lifting platform (11), and are arranged in a one-to-one correspondence with the two fixture assemblies; After the longitudinal beam front section (61) and the longitudinal beam rear section (62) are positioned and clamped by the clamp assembly, when the translation base (2) drives the longitudinal beam front section (61) and the longitudinal beam rear section (62) to move relatively close, the two cleaning assemblies (5) respectively perform synchronous cleaning on the welding overlap surfaces of the longitudinal beam front section (61) and the longitudinal beam rear section (62); when and only when the longitudinal beam front section (61) and the longitudinal beam rear section (62) are translated until the welding overlap surfaces of the two are vertically aligned, the lifting platform (11) descends, so that the welding overlap surfaces of the longitudinal beam front section (61) and the longitudinal beam rear section (62) are completely fitted and butted up and down.

2. The automatic welding system for rear longitudinal beam of an automobile according to claim 1, characterized in that: The cleaning assembly (5) comprises: Support frame (51); The cleaning component (52) is slidably mounted on the support frame (51) along the sliding direction of the translation base (2). When the translation base (2) drives the longitudinal beam front section (61) or the longitudinal beam rear section (62) to translate through the cleaning component (52), the cleaning component (52) cleans the welded overlapped surface of the longitudinal beam front section (61) or the longitudinal beam rear section (62). And a lateral swing assembly (53) is fixed on the support frame (51) and is used to drive the cleaning component (52) to swing back and forth in the moving direction of the translation base (2) to achieve reciprocating swing cleaning.

3. The automatic welding system for rear longitudinal beam of an automobile according to claim 2, characterized in that: The cleaning component (52) comprises: A sliding frame (521) is slidably mounted on the support frame (51) along the translation direction of the translation base (2); An air box (522) is fixed on the sliding frame (521) and can be used to pass gas in and out. The air box (522) is provided with an exhaust surface facing the overlap surface of the longitudinal beam front section (61) or the longitudinal beam rear section (62) and having a contour matching, and air holes are evenly opened on the exhaust surface; and a cleaning brush (523) coated on the exhaust surface of the air box (522); the cleaning brush (523) is detachably mounted on the exhaust surface of the air box (522), and the gas exhausted from the air box (522) is discharged outward from the brush layer of the cleaning brush (523).

4. The automatic welding system for rear longitudinal beam of an automobile according to claim 3, characterized in that: The air box (522) is connected to and fixed with an air pipe (5221) for inward ventilation; the swaying assembly (53) comprises: A driven block (534) is horizontally fixed at the end of the air pipe (5221), and an elongated hole extending horizontally and perpendicularly to the sliding direction of the sliding frame (521) is provided on the driven block (534); A driving motor (531) is vertically fixed on the support frame (51); and a driving disk (532) fixed on the output shaft of the driving motor (531); an eccentric pin (533) is fixed at a non-central position on the driving disk (532); and the eccentric pin (533) is inserted into the elongated hole.

5. The automatic welding system for rear longitudinal beam of an automobile according to claim 1, characterized in that: The supporting side clamping component (3) comprises: A support frame (31) for horizontally supporting and placing the front section (61) of the longitudinal beam or the rear section (62) of the longitudinal beam; And a side clamp assembly (32) is assembled on the support frame (31) and is used to clamp the outer side walls of the longitudinal beam front section (61) or the longitudinal beam rear section (62) on both sides.

6. The automatic welding system for rear longitudinal beam of an automobile according to claim 1, characterized in that: The pressing component (4) comprises: Guide rack (41); A driving assembly (42) mounted on the guide frame (41); and a pressing member, which is mounted on the driving assembly (42) and is used to press down the front section (61) of the longitudinal beam or the rear section (62) of the longitudinal beam; Under the guidance of the guide frame (41), the driving assembly (42) drives the pressing member to press down on the longitudinal beam front section (61) or the longitudinal beam rear section (62), and drives the pressing member to move away from the longitudinal beam front section (61) or the longitudinal beam rear section (62).

7. The automatic welding system for rear longitudinal beam of an automobile according to claim 5, characterized in that: The support frame (31) comprises: two side brackets (311); and a supporting plate (312) for supporting the longitudinal beam front section (61) or the longitudinal beam rear section (62) in horizontal placement and fixed horizontally between the two side brackets (311); a positioning pin (313) is fixed on the supporting plate (312) and is inserted into a fixing hole in the longitudinal beam front section (61) or the longitudinal beam rear section (62).

8. The automatic welding system for rear longitudinal beam of an automobile according to claim 7, characterized in that: The side clamp assembly (32) comprises two side clamp blocks (324) which are mounted on two side brackets (311) in a one-to-one relative horizontal sliding manner, and the side clamp blocks (324) are in flexible clamping contact with the longitudinal beam front section (61) or the longitudinal beam rear section (62).

9. The automatic welding system for rear longitudinal beam of an automobile according to claim 6, characterized in that: The guide frame (41) comprises at least one side plate (411), a track hole (413) is formed on the side plate (411), and the track hole (413) comprises an inclined section and a vertical section from top to bottom; The drive assembly (42) comprises: A driving slider (422) is mounted on the side plate (411) in a vertical sliding manner; A pressing plate (423) is mounted on the driving slider (422) in a horizontally sliding manner; and a moving pin (424) fixed on the pressing plate (423) and moving along the track hole (413), and a lower pressing piece fixed on the bottom end of the pressing plate (423); During the process of driving the slider (422) to descend, when the moving pin (424) moves along the inclined section of the track hole (413), the lower pressing piece together with the pressing piece plate (423) descends and moves horizontally toward the top of the pressed surface of the longitudinal beam front section (61) or the longitudinal beam rear section (62).

10. The automatic welding system for rear longitudinal beam of an automobile according to claim 9, characterized in that: The pressing member is a plurality of pressing rods (43) vertically fixed at the bottom end of the pressing member plate (423), and the lower ends of the pressing rods (43) are in flexible pressing contact with the front section (61) of the longitudinal beam or the rear section (62) of the longitudinal beam.

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