Automatic saddle welding device based on visual processing and using method thereof

Abstract

The invention discloses an automatic saddle welding device based on visual processing and a using method thereof, and relates to the field of saddle welding.The device comprises a conveyor, a clamping mechanism, a lifting mechanism, an electric rotating disc, a welding mechanical arm and a visual positioning device.A supporting table at the top of a base can move along a guide rail D and is matched with production line procedure arrangement; the clamping mechanism drives clamping plates to move oppositely through a screw A, flexible clamping is achieved in combination with a spring, workpiece damage is avoided, and the posture stability is guaranteed. The core logic of clamping first and then positioning is adopted, the visual positioning device accurately extracts welding seam feature point coordinates through a two-dimensional image acquisition module, a three-dimensional contour acquisition module and a light supplementing adjusting module, and the welding seam feature point coordinates are accurately obtained; positioning data are provided for a welding mechanical arm, the problem of welding deviation caused by workpiece transfer displacement, clamping posture adjustment and coordinate system difference in the prior art is effectively solved, and the defects of weld joint deviation, incomplete penetration and the like are overcome.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of saddle welding, more particularly, it relates to a saddle automatic welding device based on visual processing and a use method thereof. BACKGROUND

[0002] As a key load-bearing component in scenarios such as pipeline support and equipment installation, the structure of the saddle is mostly formed by welding an arc-shaped support plate and a reinforcing rib. The position precision and connection strength of the weld directly affect the load stability and service life of the saddle, so the automation and high precision requirements for the welding process are increasing.

[0003] In existing saddle automatic welding equipment, the mainstream positioning and welding process generally adopts the mode of "visual positioning first, then clamping and fixing": that is, the visual positioning device first performs image acquisition and feature point extraction on the freely placed saddle to be welded on the conveying line, then the workpiece is transferred to the clamping mechanism for fixing by the conveyor, and finally the welding robot performs welding operation according to the preset positioning data. However, this mode has an unavoidable position deviation problem: on the one hand, during the transfer process of the workpiece after visual positioning and before clamping, a small displacement may occur due to the wear of the conveyor roller, the shift of the workpiece center of gravity or the inertial effect, resulting in inconsistency between the actual clamping position and the reference position at the time of positioning; on the other hand, when the clamping mechanism clamps the workpiece, the clamping force may cause slight posture adjustment of the workpiece (such as change in the fit of the arc-shaped support plate and the positioning surface), further aggravating the positioning deviation; in addition, the workpiece is in a free state during visual positioning, while the workpiece is fixed after clamping, and there is a difference between the stress state and the reference coordinate system, which also causes deviation between the positioning data and the actual welding position. The above position deviation will eventually cause weld offset, incomplete penetration, undercut and other welding defects, affecting the welding quality and product consistency of the saddle, and it is difficult to meet the high-precision production requirements.

[0004] Therefore, in order to solve the above technical problems, the present application provides a saddle automatic welding device based on visual processing and a use method thereof. SUMMARY

[0005] In view of the deficiencies of the prior art, the purpose of the present application is to provide a saddle automatic welding device based on visual processing and a use method thereof.

[0006] To achieve the above purpose, the present application provides the following technical solution: a saddle automatic welding device based on visual processing, comprising: a conveyor for carrying and conveying a saddle workpiece to be welded; a clamping mechanism for clamping and fixing the saddle workpiece when it is sent to the clamping position by the conveyor; A lifting mechanism is installed above the welding position of the conveyor pair of saddles to drive the lifting of the electric turntable on which the welding mechanical arm and the visual positioning device are installed, the position of the welding mechanical arm and the visual positioning device is rotated and replaced by the electric turntable, so that the three-dimensional image acquisition and feature point coordinate extraction of the welding joint of the workpiece are carried out by the visual positioning device first, the positioning data suitable for the welding mechanical arm is generated, and then the welding joint of the workpiece is welded by the welding mechanical arm.

[0007] Preferably, the visual positioning device comprises: A two-dimensional image acquisition module: a CCD camera, used for acquiring high-definition two-dimensional images of the welding joint of the workpiece, and capturing the planar profile features of the joint; A three-dimensional profile acquisition module: provided with two laser profile sensors, symmetrically distributed on both sides of the two-dimensional image acquisition module, used for acquiring three-dimensional point cloud data of the welding joint of the workpiece, and identifying three-dimensional features such as joint height difference and arc curvature; A light supplement adjustment module: a ring-shaped LED light supplement lamp, sleeved outside the lens of the two-dimensional image acquisition module, electrically connected with the data processing module, used for eliminating environmental light interference and ensuring image acquisition clarity; A data processing module: provided with a high-performance processor and a three-dimensional point cloud processing algorithm, electrically connected with the two-dimensional image acquisition module and the three-dimensional profile acquisition module, respectively, used for receiving two-dimensional image data and three-dimensional point cloud data, and extracting the start point, end point, inflection point and weld width feature point coordinates of the welding joint after image noise reduction, edge detection, threshold segmentation and feature point matching processing, and converting the feature point coordinates into base coordinate system data of the welding mechanical arm, and finally transmitting the converted positioning data to the controller of the welding mechanical arm to provide core basis for mechanical arm welding path planning and precise welding.

[0008] Preferably, the bottom four corners of the conveyor are connected with the base through support rods, and a support table is installed on the top of the base.

[0009] Preferably, the clamping mechanism comprises a connecting shell A fixed on the top of the support table, a screw rod A driven by a motor A is installed in the connecting shell A, the threads on both sides of the screw rod A are opposite and symmetric at the middle part, a rod sleeve A is threadedly connected to the outer side wall of the screw rod A on both sides, the top end of the rod sleeve A is connected with a clamping plate through a connecting rod, the end of the screw rod A is rotatably connected with the side wall of the connecting shell A through a bearing A, a guide rail A is installed on the inner bottom wall of the connecting shell A, and the bottom end of the rod sleeve A is slidably connected in the guide rail A through a sliding block A.

[0010] Preferably, the head of the connecting rod is welded with a connecting plate, and the four corners of the connecting plate are provided with through holes, the inside of the through holes is inserted with a moving rod, the head of the moving rod is connected with the clamping plate, the tail of the moving rod is welded with a vertical plate, a plurality of springs are installed between the surface of the vertical plate and the back surface of the connecting plate, the back surface of the connecting plate is fixedly connected with guide rails B on both sides for sliding of the sliding block B, and the surface of the sliding block B is fixed with the side end of the vertical plate.

[0011] Preferably, the top of the support table is fixedly connected with a gantry plate, the lifting mechanism comprises a connecting shell B embeddedly fixed on the top plate of the gantry plate, the inside of the connecting shell B is installed with a screw rod B driven by a motor B, the outer side wall of the screw rod B is threadedly connected with a rod sleeve B, the inside of the connecting shell B is installed with guide rails C on both side walls, the two sides of the rod sleeve B are slidably connected in the guide rails C through sliding blocks C, the bottom end of the sliding block C is fixedly connected with a vertical rod, the bottom of the connecting shell B is provided with a through slot for the vertical rod to pass through, and the bottom end of the vertical rod is connected with the electric turntable through a connecting piece. The bottom of the screw rod B is rotatably connected with the inner bottom wall of the connecting shell B through a bearing B.

[0012] Preferably, the support table can move relative to the base to adjust the position of the clamping mechanism and the lifting mechanism relative to the conveyor, so as to adjust the welding position of the saddle on the conveyor.

[0013] Preferably, the bottom of the base is fixedly connected with a guide rail D in the middle part, and the bottom of the support table is slidably connected in the guide rail D through a sliding block D.

[0014] Preferably, the bottom four corners of the support table are in contact with the top of the base through the rollers with locking function.

[0015] The method for using the above-mentioned saddle automatic welding device based on visual processing comprises the following steps: Step one: when the conveyor transports the saddle workpiece to be welded to the clamping position, the conveyor triggers the limit sensor and stops running, and the workpiece is accurately parked between the two clamping plates of the clamping mechanism; Step two: start the motor A of the clamping mechanism to positive rotation, drive the screw rod A in the connecting shell A to stably rotate through the bearing A, because the threads on both sides of the screw rod A are opposite and symmetrical, the two rod sleeves A on the outside move towards each other through the bottom sliding block A along the guide rail A, drive the connecting rod and the clamping plate to approach the workpiece; Step three: when the clamping plate is in contact with the workpiece surface to form a preliminary clamping, the motor A continuously outputs driving force, prompting the moving rod to slide along the through hole of the connecting plate away from the workpiece, driving the vertical plate to move synchronously and lengthen the spring, the reverse elastic force generated by the spring is transmitted to the clamping plate through the vertical plate and the moving rod, forming a sustained buffering clamping force, at the same time, the vertical plate slides linearly along the guide rail B through the sliding block B, ensuring that the clamping force is evenly distributed, when the spring deformation reaches the preset threshold, the motor A stops running, and the workpiece is clamped stably; Step four: start the electric turntable to control its rotation, accurately switch the visual positioning device to the clamping position directly above, start the motor B of the lifting mechanism to rotate in the positive direction, drive the screw B in the connecting shell B to rotate through the bearing B, the rod sleeve B descends along the guide rail C through the sliding block C, driving the vertical rod to descend synchronously through the through slot, until the visual positioning device reaches the collection height adapted to the workpiece welding joint, the motor B stops running, and the three-dimensional image collection and feature point coordinate extraction of the welding joint of the fixed workpiece are carried out through the visual positioning device, generating positioning data adapted to the welding mechanical arm; Step five: start the motor B to reverse, drive the vertical rod to rise to the initial height, control the electric turntable to rotate again to switch the welding mechanical arm to the clamping position directly above, start the motor B again to drive the welding mechanical arm to descend to the adapted welding height; Step six: the welding mechanical arm plans the welding path according to the positioning data received by the controller, starts the welding power supply, and continuously welds along the joint; Step seven: after the welding work is completed, the welding mechanical arm stops welding and is driven by the lifting mechanism to rise to the initial height, the electric turntable rotates to reset, and the welding mechanical arm and the visual positioning device return to the non-working position; Step eight: start the motor A to reverse, drive the screw A to rotate in the reverse direction, and the two clamping plates move reversely along the guide rail A to open, releasing the clamping of the workpiece, and starting the conveyor to convey the welded saddle workpiece to the discharging area.

[0016] Compared with the prior art, the present application has the following beneficial effects: 1、The present application directly avoids the displacement deviation caused by workpiece transfer in the prior art "positioning first and clamping later" mode through the core logic of "clamping first and positioning later", and the posture and stress state of the clamped workpiece are maintained throughout the positioning and welding process, which solves the problems of posture adjustment and difference between positioning and welding reference coordinate system caused by clamping force, effectively eliminates the position deviation of the prior art, avoids defects such as weld offset, incomplete penetration and undercut, and solves the problems in the background technology. 2. The present invention uses the reverse elastic force generated by the stretching of the spring to form a continuous and buffered clamping force, which avoids damage or deformation of the saddle workpiece surface caused by rigid clamping. At the same time, it ensures that the clamping plate is always in close contact with the surface of the saddle workpiece, counteracts the slight displacement tendency of the saddle workpiece during welding, and ensures that the saddle workpiece maintains a stable posture during the positioning and welding stages, thereby improving the stability of clamping. 3. The present invention designs the support platform to be movable relative to the base in order to adjust the position of the clamping mechanism and the lifting mechanism relative to the conveyor, thereby adjusting the welding position of the saddle on the conveyor and avoiding conflicts with other processes. Attached Figure Description

[0017] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 For the present invention Figure 1 Another perspective on the specific structure; Figure 3 For the present invention Figure 1 Another angle of the specific structural diagram; Figure 4 This is a schematic diagram of the specific structure of the clamping mechanism in this invention; Figure 5 For the present invention Figure 4 Enlarged view of the local structure of A; Figure 6 For the present invention Figure 4 Based on the original design, a detailed structural diagram of the connecting shell A has been removed. Figure 7 This is a schematic diagram of the specific structure of the lifting mechanism in this invention; Figure 8 For the present invention Figure 7 Enlarged view of the local structure of B.

[0018] In the diagram: 1. Conveyor; 2. Clamping mechanism; 201. Connecting shell A; 202. Screw A; 203. Motor A; 204. Rod sleeve A; 205. Connecting rod; 206. Clamping plate; 207. Bearing A; 208. Guide rail A; 209. Slider A; 210. Connecting plate; 2101. Through hole; 211. Moving rod; 212. Vertical plate; 213. Spring; 214. Guide rail B; 215. Slider B; 3. Lifting mechanism; 301. Connecting shell B; 3011. Through groove; 302. Screw B; 303. Motor B; 304. Rod sleeve B; 305. Guide rail C; 306. Slider C; 307. Vertical rod; 308. Bearing B; 4. Electric turntable; 5. Welding robotic arm; 6. Vision positioning device; 7. Support rod; 8. Base; 9. Support platform; 10. Gantry plate; 11. Guide rail D; 12. Slider D; 13. Roller. Detailed Implementation

[0019] Example 1 like Figures 1 to 3 As shown, the present invention provides an automated saddle welding device based on vision processing, comprising: Conveyor 1 is used to carry and transport the saddle workpiece to be welded; Clamping mechanism 2 clamps and fixes the saddle workpiece when it sends the conveyor 1 to the clamping position; The lifting mechanism 3 is installed above the welding position of the saddle on the conveyor 1 (i.e., the clamping position of the saddle) and is used to drive the lifting of the electric turntable 4. The electric turntable 4 is equipped with a welding robot arm 5 and a vision positioning device 6. The electric turntable 4 rotates and replaces the positions of the welding robot arm 5 and the vision positioning device 6. Thus, the vision positioning device 6 first performs three-dimensional image acquisition of the welding joint of the workpiece and extracts the coordinates of the feature points, generating positioning data adapted to the welding robot arm 5, and then the welding robot arm 5 welds the workpiece.

[0020] Conveyor 1 carries the saddle workpiece to be welded and transports it to the clamping position. First, the clamping mechanism 2 clamps and fixes the workpiece. Then, the position is adjusted by rotating the electric turntable 4, precisely switching the vision positioning device 6 to directly above the clamping position. The lifting mechanism 3 drives the electric turntable 4 to descend, bringing the vision positioning device 6 to the appropriate image acquisition height. The vision positioning device 6 performs three-dimensional image acquisition and feature point coordinate extraction of the weld joint on the fixed workpiece, generating positioning data suitable for the welding robot arm 5. Afterward, the lifting mechanism 3 drives the electric turntable 4 to rise, and the electric turntable 4 rotates again to achieve position replacement, moving the welding robot arm 5 to the clamping position. Positioned directly above, the lifting mechanism 3 adjusts the electric turntable 4 to a suitable height according to welding requirements. The welding robotic arm 5 performs high-precision welding on the workpiece weld joint based on the precise positioning data generated by the vision positioning device 6. This process directly avoids the displacement deviation caused by workpiece transfer in the existing technology's "positioning first, clamping later" mode through the core logic of "clamping first, positioning later". At the same time, the posture and force state of the workpiece after clamping are consistent throughout the entire process from positioning to welding, fundamentally solving the problem of posture adjustment caused by clamping force and the difference between positioning and welding reference coordinate system. This effectively eliminates the position deviation of the existing technology and avoids defects such as weld offset, incomplete penetration, and undercut.

[0021] Wherein, the visual positioning device 6 comprises a two-dimensional image acquisition module, a three-dimensional profile acquisition module, a light supplement adjustment module and a data processing module. When the visual positioning device 6 works, firstly, the light supplement adjustment module adjusts the light intensity of the annular LED light supplement lamp in the range of 1000-10000 lux according to the environmental light intensity, eliminates the environmental light interference to ensure the image acquisition clarity; then, the two-dimensional image acquisition module (a CCD camera with pixel resolution ≥ 5 million) and the three-dimensional profile acquisition module (two laser profile sensors with z-axis resolution ≤ 1 μm symmetrically distributed on both sides of the two-dimensional image acquisition module) symmetrically distributed on both sides thereof are started synchronously, respectively collect high-definition two-dimensional images of the workpiece welding seams to capture the planar profile features, collect three-dimensional point cloud data to identify the three-dimensional features such as the seam height difference and the arc curvature; then, the data processing module receives and integrates the two-dimensional image data and the three-dimensional point cloud data through the built-in high-performance processor and the three-dimensional point cloud processing algorithm, after a series of processing such as image noise reduction, edge detection, threshold segmentation and feature point matching, accurately extracts the feature point coordinates of the starting point, the ending point, the inflection point and the weld width of the welding seam, and then converts these feature point coordinates into the base coordinate system data of the welding robot 5, and finally transmits the converted positioning data to the controller of the welding robot 5, to provide the core basis for the robot to plan the welding path and realize precise welding.

[0022] Example 2 As Figures 1-8As shown, the embodiment gives the specific structure of the clamping mechanism 2 and the lifting mechanism 3 in example 1: the bottom four corners of the conveyor 1 are connected with the base 8 through the support rod 7, the top of the base 8 is provided with the support table 9, the clamping mechanism 2 includes the connecting shell A201 fixed on the top of the support table 9, the inside of the connecting shell A201 is provided with the screw A202 driven by the motor A203, the threads of the two sides of the screw A202 are opposite and symmetrical at the middle part, the outside wall of the screw A202 is threadedly connected with the rod sleeve A204 on both sides, the top end of the rod sleeve A204 is connected with the clamping plate 206 through the connecting rod 205, the end of the screw A202 is rotatably connected with the side wall of the connecting shell A201 through the bearing A207, the inner bottom wall of the connecting shell A201 is provided with the guide rail A208, the bottom end of the rod sleeve A204 is slidably connected in the guide rail A208 through the sliding block A209, the head of the connecting rod 205 is welded with the connecting plate 210, the four corners of the connecting plate 210 are provided with the through hole 2101, the moving rod 211 is inserted in the through hole 2101, the head of the moving rod 211 is connected with the clamping plate 206, the tail is welded with the vertical plate 212, a plurality of springs 213 are installed between the surface of the vertical plate 212 and the back surface of the connecting plate 210, the back surface of the connecting plate 210 is fixedly connected with the guide rail B214 for sliding of the sliding block B215, the surface of the sliding block B215 is fixed with the side end of the vertical plate 212, the top of the support table 9 is fixedly connected with the gantry plate 10, the lifting mechanism 3 includes the connecting shell B301 embeddedly fixed on the top plate of the gantry plate 10, the inside of the connecting shell B301 is provided with the screw B302 driven by the motor B303, the outside wall of the screw B302 is threadedly connected with the rod sleeve B304, the inside of the connecting shell B301 is provided with the guide rail C305 on both side walls, the two sides of the rod sleeve B304 are slidably connected in the guide rail C305 through the sliding block C306, the bottom end of the sliding block C306 is fixedly connected with the vertical rod 307, the bottom of the connecting shell B301 is provided with the through slot 3011 for the vertical rod 307 to pass through, the bottom end of the vertical rod 307 is connected with the electric turntable 4 through the connecting piece, the bottom of the screw B302 is rotatably connected with the inner bottom wall of the connecting shell B301 through the bearing B308.

[0023] The conveyor 1 is fixed above the base 8 by the support rods 7 at the four corners of the bottom, and the support table 9 is installed on the top of the base 8 and provides a mounting reference for the two mechanisms. When the conveyor 1 delivers the saddle-shaped workpiece to be welded to the clamping position, the conveyor 1 stops running, the motor A203 of the clamping mechanism 2 starts, and the control of the forward rotation drives the screw A202 in the connecting shell A201 to rotate (the stability of the rotation of the screw A202 is improved through the bearing A207). Due to the opposite and symmetrical distribution of the threads on both sides of the screw A202, the two rod sleeves A204 connected by the outer wall threads move towards each other along the guide rails A208 on the bottom wall in the connecting shell A201 through the sliders A209 at the bottom, thereby driving the connecting rods 205 at the top and the clamping plates 206 to approach the saddle-shaped workpiece. When the clamping plates 206 come into contact with the surface of the saddle-shaped workpiece and form a preliminary clamping, the continuous driving force of the screw A202 will cause the moving rod 211 to slide along the through hole 2101 on the connecting plate 210 in a direction away from the saddle-shaped workpiece. At this time, the vertical plate 212 welded at the tail of the moving rod 211 will move synchronously, so that the multiple springs 213 installed between the vertical plate 212 and the back of the connecting plate 210 are elongated and elastically deformed. The reverse elastic force generated during the deformation of the springs 213 will be transmitted to the clamping plate 206 through the vertical plate 212 and the moving rod 211. At the same time, the vertical plate 212 will drive the slider B215 to slide along the guide rail B214 during the movement, keeping the vertical plate 212 moving linearly back and forth (to avoid the inclination of the vertical plate 212). The reverse elastic force generated by the elongation of the springs 213 forms a continuous and bufferable clamping force, avoiding the surface damage or deformation of the saddle-shaped workpiece caused by rigid clamping. At the same time, the clamping plate 206 is always closely attached to the surface of the saddle-shaped workpiece, offsetting the slight displacement trend of the saddle-shaped workpiece during welding, ensuring that the posture of the saddle-shaped workpiece remains stable during positioning and welding, and improving the stability of clamping (by controlling the reverse rotation of the motor A203, the two clamping plates 206 move in opposite directions to release the clamping of the saddle-shaped workpiece). The gantry plate 10 on the top of the support table 9 provides a mounting carrier for the lifting mechanism 3. The motor B303 of the lifting mechanism 3 is started and drives the screw B302 in the connecting shell B301 to rotate (by controlling the forward rotation or reverse rotation of the motor B303, the screw B302 is correspondingly rotated to realize the lifting of the rod sleeve B304, and the stability of the rotation of the screw B302 is improved through the bearing B308). The rod sleeve B304 slides up and down along the guide rails C305 on the two side walls in the connecting shell B301 through the sliders C306 on both sides, drives the vertical rod 307 at the bottom end of the slider C306 to synchronously rise and fall through the through slot 3011 at the bottom of the connecting shell B301, and drives the electric turntable 4 to adjust the height through the connecting piece at the bottom end of the vertical rod 307, thereby cooperating with the image acquisition of the visual positioning device 6 and the welding operation of the welding mechanical arm 5.

[0024] Example 3 As Figures 1-3As shown, the support table 9 in this embodiment is designed to be movable relative to the base 8 to adjust the position of the clamping mechanism 2 and the lifting mechanism 3 relative to the conveyor 1, so as to adjust the welding position (welding station) of the saddle on the conveyor 1, avoid conflict with other processes, and avoid space overlap or interference between the welding station and the devices, operation channels or workpiece transfer paths of other processes. The movable support table 9 can flexibly adapt to the process arrangement requirements of the production line.

[0025] The specific structure of the movable support table 9 is as follows: the middle part of the bottom of the base 8 is fixedly connected with a guide rail D11, and the middle part of the bottom of the support table 9 is slidably connected in the guide rail D11 through a sliding block D12. The four corners of the bottom of the support table 9 are in contact with the top of the base 8 through rollers 13 with locking function.

[0026] The guide rail D11 fixedly connected to the middle part of the bottom of the base 8 provides accurate movement guidance for the support table 9. The sliding block D12 at the middle part of the bottom of the support table 9 is in sliding cooperation with the guide rail D11, so as to ensure that the support table 9 can only move linearly along the direction of the guide rail D11. Meanwhile, the rollers 13 with locking function at the four corners of the bottom of the support table 9 are in contact with the top of the base 8, which not only shares the weight of the support table 9 and the components above, such as the clamping mechanism 2 and the lifting mechanism 3, but also reduces the resistance when the support table 9 moves through rolling friction, so that the position adjustment is more labor-saving and convenient. When it is necessary to adjust the welding position to avoid conflict with other processes, the locking function of the rollers 13 is first unlocked, and the support table 9 can be smoothly moved through the cooperation of the sliding block D12 and the guide rail D11. After moving to the target position, the rollers 13 are locked to fix the support table 9 relative to the base 8, so as to ensure that the support table 9 does not displace when the clamping mechanism 2 clamps the workpiece and the lifting mechanism 3 drives the welding operation.

[0027] The application also provides a use method of the saddle automatic welding device with the above-mentioned visual processing: Step one: when the conveyor 1 conveys the workpiece to be welded to the clamping position, the conveyor 1 triggers the limit sensor and stops running, and the workpiece is accurately parked between the two clamping plates 206 of the clamping mechanism 2; Step two: the motor A203 of the clamping mechanism 2 is started and rotates forward, driving the screw A202 in the connecting shell A201 to stably rotate through the bearing A207. Since the threads on both sides of the screw A202 are opposite and symmetrical, the two rod sleeves A204 on the outside move towards each other along the guide rail A208 through the bottom end sliding block A209, driving the connecting rod 205 and the clamping plate 206 to approach the workpiece. Step three: when the clamping plate 206 is in contact with the workpiece surface to form a preliminary clamping, the motor A 203 continuously outputs driving force, which promotes the moving rod 211 to slide along the through hole 2101 of the connecting plate 210 away from the workpiece, drives the vertical plate 212 to move synchronously and lengthens the spring 213, the reverse elastic force generated by the spring 213 is transmitted to the clamping plate 206 through the vertical plate 212 and the moving rod 211, forming a sustained buffering clamping force, at the same time, the vertical plate 212 slides linearly along the guide rail B 214 through the sliding block B 215, ensuring that the clamping force is uniformly distributed, and when the deformation of the spring 213 reaches the preset threshold, the motor A 203 stops running, and the workpiece is stably clamped; Step four: start the electric turntable 4 to control its rotation, accurately switch the visual positioning device 6 to the clamping position directly above, start the motor B 303 of the lifting mechanism 3 to rotate in the positive direction, drive the screw B 302 in the connecting shell B 301 to rotate through the bearing B 308, drive the rod sleeve B 304 to descend through the sliding block C 306 along the guide rail C 305, drive the vertical rod 307 to descend synchronously through the through slot 3011, until the visual positioning device 6 reaches the collection height adapted to the workpiece welding joint, stop the motor B 303, collect the three-dimensional image of the workpiece welding joint and extract the characteristic point coordinates through the visual positioning device 6, and generate the positioning data adapted to the welding mechanical arm 5; Step five: start the motor B 303 to reverse, drive the vertical rod 307 to rise to the initial height, control the electric turntable 4 to rotate again, switch the welding mechanical arm 5 to the clamping position directly above, start the motor B 303 again, drive the welding mechanical arm 5 to descend to the adapted welding height; Step six: the welding mechanical arm 5 plans the welding path according to the positioning data received by the controller, starts the welding power supply, and continuously welds along the joint; Step seven: after the welding work is completed, the welding mechanical arm 5 stops welding and is driven by the lifting mechanism 3 to rise to the initial height, the electric turntable 4 rotates to reset, and the welding mechanical arm 5 and the visual positioning device 6 return to the non-working position; Step eight: start the motor A 203 to reverse, drive the screw A 202 to rotate in the reverse direction, and the two clamping plates 206 move in the reverse direction along the guide rail A 208 to open, thereby releasing the clamping of the workpiece, and starting the conveyor 1 to convey the welded saddle workpiece to the discharging area.

[0028] The saddle automatic welding device based on visual processing and the use method thereof have the following advantages: Through the core logic of "clamping first and then positioning", the displacement deviation caused by workpiece transfer in the prior art "positioning first and then clamping" mode is directly avoided, and the posture and stress state of the clamped workpiece are maintained throughout the positioning and welding process, which fundamentally solves the problems of posture adjustment and difference between positioning and welding reference coordinate systems caused by clamping force, effectively eliminates the positional deviation of the prior art, and avoids defects such as weld offset, incomplete penetration and undercut. The reverse elastic force generated by the spring 213 being stretched forms a sustained and cushionable clamping force, avoiding the saddle workpiece surface damage or deformation caused by rigid clamping, at the same time, the clamping plate 206 and the saddle workpiece surface are always closely fitted, offsetting the slight displacement trend of the saddle workpiece during welding, ensuring that the saddle workpiece keeps stable posture during positioning and welding stage, improving the stability of clamping; The support table 9 is designed to be movable relative to the base 8 to adjust the position of the clamping mechanism 2 and the lifting mechanism 3 relative to the conveyor 1, so as to adjust the welding position of the saddle on the conveyor 1, avoiding conflict with other processes.

[0029] The above is only a preferred embodiment of the present application, and does not limit the present application in any form; any ordinary skilled person in the industry can easily implement the present application according to the drawings and the above description; however, any slight changes, modifications and equivalent changes made by those skilled in the art within the scope of the technical solutions of the present application, using the above disclosed technical content, are equivalent embodiments of the present application; at the same time, any equivalent changes, modifications and evolution of the above embodiments according to the essential technology of the present application are still within the protection scope of the technical solutions of the present application.

Claims

1. A saddle automated welding device based on visual processing, characterized by: The utility model relates to a welding device for saddle-shaped workpiece, which comprises: a conveyor (1) for carrying and conveying the saddle-shaped workpiece to be welded; a clamping mechanism (2) for clamping and fixing the saddle-shaped workpiece when the conveyor (1) is sent to the clamping position; a lifting mechanism (3) installed above the conveyor (1) for driving the lifting of an electric turntable (4) on which a welding robot (5) and a visual positioning device (6) are installed, so that the position of the welding robot (5) and the visual positioning device (6) is rotated and replaced by the electric turntable (4), thereby the visual positioning device (6) is used to collect the three-dimensional image of the welding joint of the workpiece and extract the characteristic point coordinates, and the welding robot (5) is used to weld the workpiece according to the positioning data.

2. The vision processing based automated saddle welding apparatus as claimed in claim 1, wherein: The visual positioning device (6) comprises: a two-dimensional image acquisition module, which is a CCD camera, for collecting high-definition two-dimensional images of the welding joint of the workpiece and capturing the planar profile features of the joint; a three-dimensional profile acquisition module, which is provided with two laser profile sensors symmetrically distributed on both sides of the two-dimensional image acquisition module, for collecting three-dimensional point cloud data of the welding joint of the workpiece and identifying three-dimensional features such as the height difference and the arc curvature of the joint; a light supplement adjustment module, which is a ring-shaped LED light supplement lamp, sleeved outside the lens of the two-dimensional image acquisition module and electrically connected with the data processing module, for eliminating the interference of ambient light and ensuring the clarity of image acquisition; a data processing module, which is internally provided with a high-performance processor and a three-dimensional point cloud processing algorithm and is electrically connected with the two-dimensional image acquisition module and the three-dimensional profile acquisition module, for receiving two-dimensional image data and three-dimensional point cloud data, processing the data through image noise reduction, edge detection, threshold segmentation and feature point matching, extracting the characteristic point coordinates of the start point, end point, inflection point and weld width of the welding joint, converting the characteristic point coordinates into the base coordinate system data of the welding robot (5), and finally transmitting the converted positioning data to the controller of the welding robot (5) to provide the core basis for the welding robot to plan the welding path and realize precise welding.

3. The vision processing based automated saddle welding apparatus as claimed in claim 1, wherein: The bottom of the conveyor (1) is connected with the base (8) through support rods (7) at four corners.

4. The vision processing based automated saddle welding apparatus as claimed in claim 3, wherein: The clamping mechanism (2) comprises a connecting shell A (201) fixed on the top of the support table (9), the inside of the connecting shell A (201) is provided with a screw rod A (202) driven by a motor A (203), the threads on both sides of the screw rod A (202) are opposite and symmetrical at the middle part, the outer walls of both sides of the screw rod A (202) are threadedly connected with rod sleeves A (204), the top ends of the rod sleeves A (204) are connected with a clamping plate (206) through connecting rods (205), the end part of the screw rod A (202) is rotatably connected with the side wall of the connecting shell A (201) through a bearing A (207), the inner bottom wall of the connecting shell A (201) is provided with a guide rail A (208), and the bottom ends of the rod sleeves A (204) are slidably connected in the guide rail A (208) through sliding blocks A (209).

5. The vision processing based automated saddle welding apparatus as claimed in claim 4, wherein: The head of the connecting rod (205) is welded with a connecting plate (210), and the four corners of the connecting plate (210) are provided with through holes (2101), the inside of the through hole (2101) is inserted with a moving rod (211), the head of the moving rod (211) is connected with the clamping plate (206), the tail is welded with a vertical plate (212), a plurality of springs (213) are installed between the surface of the vertical plate (212) and the back of the connecting plate (210), the back of the connecting plate (210) is fixedly connected with guide rails B (214) for sliding of the sliding block B (215) on both sides, and the surface of the sliding block B (215) is fixed with the side end of the vertical plate (212).

6. The vision processing based automated saddle welding apparatus as claimed in claim 3, wherein: The top of the support table (9) is fixedly connected with a gantry plate (10), the lifting mechanism (3) comprises a connecting shell B (301) embeddedly fixed on the top plate of the gantry plate (10), the inside of the connecting shell B (301) is provided with a screw rod B (302) driven by a motor B (303), the outer side wall of the screw rod B (302) is threadedly connected with a rod sleeve B (304), the inside of the connecting shell B (301) is provided with guide rails C (305) on both side walls, the two sides of the rod sleeve B (304) are slidably connected in the guide rails C (305) through sliding blocks C (306), the bottom ends of the sliding blocks C (306) are fixedly connected with vertical rods (307), the bottom of the connecting shell B (301) is provided with a through slot (3011) for the vertical rods (307) to pass through, the bottom ends of the vertical rods (307) are connected with the electric rotating disc (4) through connecting pieces, and the bottom of the screw rod B (302) is rotatably connected with the inner bottom wall of the connecting shell B (301) through a bearing B (308).

7. The vision processing based automated saddle welding apparatus as claimed in claim 3, wherein: The support table (9) can move relative to the base (8) to adjust the position of the clamping mechanism (2) and the lifting mechanism (3) relative to the conveyor (1), so as to adjust the welding position of the saddle on the conveyor (1).

8. The vision processing based automated saddle welding apparatus as claimed in claim 7, wherein: The bottom of the base (8) is fixedly connected with a guide rail D (11) at the middle position, and the bottom of the support table (9) is slidably connected in the guide rail D (11) through a sliding block D (12).

9. The vision processing based automated saddle welding apparatus as claimed in claim 8, wherein: The bottom of the support table (9) is in contact with the top of the base (8) through the rollers (13) with locking function at the four corners.

10. Use of a visual process based saddle automated welding device according to any one of claims 1-9, characterized in that: The method comprises the following steps: Step one: when the conveyor (1) conveys the workpiece to be welded to the clamping position, the conveyor (1) triggers the limit sensor and stops running, and the workpiece is accurately parked between the two clamping plates (206) of the clamping mechanism (2); Step two: start the motor A (203) of the clamping mechanism (2) to rotate in the forward direction, drive the screw rod A (202) in the connecting shell A (201) to stably rotate through the bearing A (207), because the threads on both sides of the screw rod A (202) are opposite and symmetrical, the two rod sleeves A (204) on the outside move towards each other along the guide rail A (208) through the bottom end sliding block A (209), drive the connecting rod (205) and the clamping plate (206) to approach the workpiece; Step three: After the clamping plate (206) makes initial contact with the workpiece surface to form a preliminary clamping, motor A (203) continues to output driving force, prompting the moving rod (211) to slide along the through hole (2101) of the connecting plate (210) away from the workpiece, driving the vertical plate (212) to move synchronously and lengthen the spring (213), the reverse elastic force generated by the spring (213) is transmitted to the clamping plate (206) through the vertical plate (212) and the moving rod (211), forming a sustained and buffered clamping force, at the same time, the vertical plate (212) slides along the guide rail B (214) through the slider B (215), ensuring uniform distribution of clamping force, when the spring (213) deforms to a preset threshold, motor A (203) stops running, and the workpiece is firmly clamped; Step four: Start the electric turntable (4) to control its rotation, accurately switch the visual positioning device (6) to the clamping position directly above, start the motor B (303) of the lifting mechanism (3) to rotate clockwise, drive the screw B (302) in the connecting shell B (301) to rotate through the bearing B (308), the rod sleeve B (304) descends along the guide rail C (305) through the slider C (306), driving the vertical rod (307) to descend synchronously through the through slot (3011), until the visual positioning device (6) reaches the collection height adapted to the workpiece welding joint, the motor B (303) stops running, and the three-dimensional image collection and feature point coordinate extraction of the workpiece welding joint are performed through the visual positioning device (6), generating positioning data adapted to the welding robot arm (5); Step five: Start motor B (303) to reverse, drive vertical rod (307) to rise to the initial height, control electric turntable (4) to rotate again, switch welding robot arm (5) to the clamping position directly above, start motor B (303) again, drive welding robot arm (5) to descend to the adapted welding height; Step six: The welding robot arm (5) plans the welding path according to the positioning data received by the controller, starts the welding power supply, and performs continuous welding operation along the joint; Step seven: After the welding operation is completed, the welding robot arm (5) stops welding and is driven by the lifting mechanism (3) to rise to the initial height, the electric turntable (4) rotates to reset, and the welding robot arm (5) and the visual positioning device (6) return to the non-working position; Step eight: Start motor A (203) to reverse, drive screw A (202) to rotate in reverse, two clamping plates (206) move reversely along guide rail A (208) to open, releasing the clamping of the workpiece, start the conveyor (1) to convey the welded saddle workpiece to the discharging area.

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