Automatic assembly welding tool for thin-walled cylindrical girth weld and welding method thereof

Abstract

This invention discloses an automatic welding fixture and welding method for thin-walled cylindrical circumferential welds. A drive mechanism rotates a drive disc, and a guide sliding structure causes several tensioning components to radially expand relative to the rotating disc assembly and press against the joint between the upper and lower thin-walled cylinders. Then, a first and a second rotary pressing cylinder press down on the flanges of the upper and lower thin-walled cylinders respectively. Simultaneously, a venting plate is directly integrated onto the outer wall of the arc-shaped outer support of the tensioning components. The venting plate is used to purge the joint between the upper and lower thin-walled cylinders with protective gas. This method offers high processing accuracy, convenient operation, and improves processing efficiency and structural compactness.

Description

Technical Field

[0001] This invention relates to the field of thin-walled cylindrical welding technology, and in particular to an automatic welding fixture and welding method for circumferential welds of thin-walled cylindrical tubes. Background Technology

[0002] like Figure 1 As shown, a thin-walled cylinder 7 in the prior art is composed of an upper thin-walled cylinder 71 and a lower thin-walled cylinder 72. A flange 721 is fixedly connected to the outer bottom edge of the lower thin-walled cylinder 72. During processing, the upper thin-walled cylinder 71 is coaxially stacked on the lower thin-walled cylinder 72, making the outer walls of the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72 flush. Then, a ring welding process is used to weld the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72 together, forming a welded shape between them. The circumferential weld seam is used to assemble the thin-walled cylinder 7. In factories, manual welding is usually used. This manual welding method generally requires two or more people to work together. One person is responsible for stacking the upper thin-walled cylinder 71 concentrically on the lower thin-walled cylinder 72, so that the outer walls of the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72 correspond and remain aligned. The other person then uses a welding machine to perform circumferential welding on the joint between the two. The manual operation method has the defects of low processing accuracy and low processing efficiency, which urgently needs to be improved. Summary of the Invention

[0003] The purpose of this invention is to provide an automatic assembly welding fixture and welding method for thin-walled cylindrical circumferential welds, which has the advantages of high processing accuracy, convenient operation, improved processing efficiency and structural compactness, and automated processing to improve production safety.

[0004] The above-mentioned technical objective of the present invention is achieved through the following technical solution: an automatic welding fixture for thin-walled cylindrical circumferential welds, comprising a base body and a rotating disk assembly disposed on the base body, wherein a drive disk is rotatably disposed on the rotating disk assembly, and a plurality of tensioning members are arranged in a ring on the rotating disk assembly, wherein each tensioning member comprises a sliding rod portion and an arc-shaped outer support portion, wherein the plurality of sliding rod portions are distributed radially along the rotating disk assembly, and a guide sliding structure is provided between the end of the sliding rod portion away from the arc-shaped outer support portion and the drive disk, wherein a drive mechanism is also provided on the rotating disk assembly, the drive mechanism drives the drive disk to rotate, and drives the plurality of tensioning members to perform centripetal or centrifugal motion relative to the rotating disk assembly through the guide sliding structure; The rotating disk assembly is provided with a plurality of first rotating pressing cylinders. The output end of the first rotating pressing cylinder is connected to a first pressing block. A pressing plate is floating on the rotating disk assembly. The first rotating pressing cylinder drives the first pressing block to press down the pressing plate, so that the pressing plate and the upper thin-walled cylinder press down into contact. The base body is provided with a plurality of second rotary pressing cylinders spaced around the circumference of the rotating disk assembly. The output end of the second rotary pressing cylinder is connected to a second pressing block. The second rotary pressing cylinder is used to drive the second pressing block to press down on the flange. A vent plate is embedded on the outer wall of the arc-shaped outer support part away from the sliding rod part. The outer wall of the vent plate has several vent holes for gas protection of the weld during welding. The air inlet end of the vent plate is connected to a protective gas supply device.

[0005] By adopting the above technical solution, firstly, a drive mechanism drives several tensioning components to move centripetally relative to the rotating disk assembly to a retracted state. Then, the lower thin-walled cylinder and the upper thin-walled cylinder are stacked sequentially on the base body, so that the lower and upper thin-walled cylinders are fitted outside the rotating disk assembly. Then, the drive mechanism drives several tensioning components to move centrifugally to an unfolded state, so that the arc-shaped outer support of the tensioning components abuts against the joint between the upper and lower thin-walled cylinders, ensuring that the upper and lower thin-walled cylinders maintain a high degree of concentricity in the vertical direction. Then, several second rotating downward pressing cylinders on the base body drive the second pressing blocks to press down on the flange of the lower thin-walled cylinder, thereby ensuring that the bottom of the lower thin-walled cylinder is always tightly fitted with the upper end face of the base body, and that the height of each point on the ring edge of the lower thin-walled cylinder remains consistent. Several first rotating downward pressing cylinders on the rotating disk assembly drive the first pressing block to press down the upper thin-walled cylinder, ensuring that the contact surfaces between the upper and lower thin-walled cylinders are tightly fitted. Finally, the joint between the upper and lower thin-walled cylinders is welded by a ring welding process. During the welding process, the protective gas supply device provides inert protective gas to the vent plate. The vent plate continuously blows the protective gas at the joint between the upper and lower thin-walled cylinders through the vent holes, reducing welding defects between the upper and lower thin-walled cylinders. In addition, the vent plate of this device is directly integrated into the tensioning component, improving the structural compactness and ease of operation of the device. This invention has the effects of high processing accuracy, convenient operation, improved processing efficiency and structural compactness, and automated processing to improve production safety.

[0006] A further feature of the present invention is that: the outer wall of the arc-shaped outer support is provided with an annular groove along the length direction, the vent plate is embedded in the annular groove, the arc-shaped outer support is provided with an airflow channel communicating with the annular groove, the air inlet end of the airflow channel is connected to an air inlet connector, and the air outlet end of the airflow channel is connected to the vent plate.

[0007] By adopting the above technical solution, the vent plate is semi-concealed and embedded on the outer wall of the arc-shaped outer support, avoiding direct contact between the vent plate and the upper or lower thin-walled cylinder, and ensuring that the protective gas ejected from the vent holes of the vent plate can always act on the joint between the upper and lower thin-walled cylinders to achieve inert gas protection.

[0008] A further configuration of the present invention is as follows: the tensioning member is slidably disposed on the rotating disk assembly; the guide sliding structure includes a guide post and an arc-shaped groove; the guide post is fixedly connected to one end of the slide rod portion away from the arc-shaped outer support portion; a plurality of the arc-shaped grooves are arranged in a ring array on the drive disk; the arc-shaped groove includes a proximal end near the center of the drive disk and a distal end away from the center of the drive disk; the distance between the arc-shaped groove and the center of the drive disk gradually increases from the proximal end to the distal end; and the guide post and the arc-shaped groove are guided and engaged.

[0009] By adopting the above technical solution, since the tensioning member is slidably set on the rotating disk assembly, the tensioning member can make centripetal or centrifugal motions when the driving disk rotates forward or reverse, thanks to the guiding effect of multiple arc-shaped grooves and corresponding guide columns arranged along the drive disk.

[0010] A further configuration of the present invention is as follows: a first bearing is provided at one end of the guide post away from the slide bar, and a stepped groove is provided in the opening of the drive disc on the surface of the arc-shaped groove, wherein the first bearing is rotatably disposed in the stepped groove.

[0011] By adopting the above technical solution, the first bearing and the stepped groove roll together, changing the sliding friction between the guide post and the arc groove to the rolling friction between the first bearing and the stepped groove, thereby improving the smoothness of the sliding of the tensioning member relative to the drive disc.

[0012] A further feature of the present invention is that one end of the sliding rod is connected to the center position of the arc-shaped outer support, so that the tensioning member has a T-shaped symmetrical structure.

[0013] By adopting the above technical solution, the axis of the sliding rod coincides with the center of symmetry of the arc-shaped outer support, providing uniform support force to the arc-shaped outer support. This ensures that the stress distribution of the arc-shaped outer support on both sides of the sliding part is uniform and consistent, effectively avoiding the problem of deformation caused by uneven force on one side of the arc-shaped outer support.

[0014] A further feature of the present invention is that: a slide rail is fixedly provided at the bottom of the slide rod part along the length direction; a plurality of sliders are arranged in a ring on the rotating disk assembly; the plurality of sliders are spaced apart on the circumference of the rotating disk assembly; the sliders are provided with grooves corresponding to the slide rails; and the slide rails and the grooves are guided and engaged.

[0015] By adopting the above technical solution, the slide bar can slide smoothly in the radial direction relative to the rotating disk assembly, thereby improving the consistency of the sliding direction of the tensioning member relative to the rotating disk assembly.

[0016] A further configuration of the present invention is as follows: the driving mechanism includes a first driving motor and a first driving gear connected to the power output end of the first driving motor, and the outer wall of the driving disk is provided with a first external gear ring corresponding to the first driving gear, and the first driving gear meshes with the first external gear ring.

[0017] By adopting the above technical solution, the first drive motor drives the first drive gear to rotate, and the first drive gear then drives the drive disk to rotate forward or backward through the first external gear ring.

[0018] A further configuration of the present invention is as follows: the pressure plate presses against the lower thin-walled cylinder to make it abut against the lower thin-walled cylinder; the pressure plate has an clearance hole corresponding to the first pressure block; and the first rotating pressing cylinder is used to drive the first pressure block to rotate and switch between a clearance position and a stop position relative to the clearance hole.

[0019] By adopting the above technical solution, the pressure plate can achieve overall pressing and positioning of the upper thin-walled cylinder, ensuring the coaxiality and end face fit between the upper and lower thin-walled cylinders. When the first rotating pressing cylinder drives the first pressing block to rotate into the clearance hole, the pressure plate can be freely picked up and put in, which facilitates the loading, unloading and pre-placement of workpieces, and greatly improves the assembly efficiency.

[0020] A further configuration of the present invention is as follows: the rotating disk assembly includes a rotating platform and a rotating base concentrically connected to the rotating platform; a second external gear ring is coaxially fixed outside the rotating base; the rotating base is rotatably connected to the middle part of the base body; the base body is provided with a second drive motor; the power output end of the second drive motor is connected to a second drive gear; the second drive gear meshes with the second external gear ring.

[0021] By adopting the above technical solution, the second drive motor drives the rotating base and the rotating table to rotate coaxially through gear meshing, which can drive the upper thin-walled cylinder and the lower thin-walled cylinder to rotate continuously. With the help of the fixed welding gun, the entire circumferential weld can be continuously welded in one go, avoiding joint defects caused by segmented welding, improving the integrity and appearance quality of the weld. In addition, the second drive gear meshes with the second external gear ring, with accurate transmission ratio and high rotational precision, which can effectively control the stability of the rotation speed, avoid workpiece shaking and eccentricity, ensure the stability of the gap between the welding gun and the weld, and significantly improve the welding quality and consistency of the circumferential weld.

[0022] This invention provides a welding method for an automatic assembly welding fixture for thin-walled cylindrical circumferential welds, comprising the following steps: S1: Tooling pre-adjustment and workpiece loading: The drive mechanism drives several tensioning parts to move centripetally relative to the rotating disk assembly to the storage state. Then, the lower thin-walled cylinder and the upper thin-walled cylinder are coaxially stacked on the base body in sequence, so that the lower thin-walled cylinder and the upper thin-walled cylinder are coaxially sleeved on the outside of the rotating disk assembly in the vertical direction, thus completing the initial positioning of the workpiece. S2: Workpiece clamping and fixing: Control the drive mechanism to reverse the action, drive several tensioning parts to perform centrifugal expansion motion to the unfolded working state, so that the arc-shaped outer support part at the end of each tensioning part synchronously abuts against the inner side of the circumferential joint formed by the upper thin-walled cylinder and the lower thin-walled cylinder. Through the synchronous outer support action of multiple sets of tensioning parts, ensure that the upper thin-walled cylinder and the lower thin-walled cylinder maintain strict coaxiality in the vertical direction, and achieve uniform calibration of the circumferential gap of the joint. S3: Workpiece clamping and fixing: Several second rotary pressing cylinders on the base body drive the second pressing blocks to press down on the flange of the thin-walled cylinder, so that the bottom end face of the thin-walled cylinder is tightly fitted with the upper end face of the base body, and the height and level of each point on the circumferential edge of the thin-walled cylinder are consistent. At the same time, several first rotary pressing cylinders on the rotating disk assembly drive each first pressing block to press down against the corresponding part of the upper end of the thin-walled cylinder, and press the mating surface of the upper thin-walled cylinder and the lower thin-walled cylinder. S4: First Intermittent Circumferential Welding: Using a circumferential welding process, the circumferential butt joint between the upper thin-walled cylinder and the lower thin-walled cylinder is intermittently welded at equal intervals and with equal arc lengths. Throughout the welding operation, the protective gas supply device is activated, which continuously supplies inert protective gas to the ventilation plate. The ventilation plate delivers the inert protective gas continuously and evenly to the welding area of ​​the circumferential butt joint through the pre-set ventilation holes on the plate, thus isolating the air and forming an inert protective atmosphere. S5: Welding Station Adjustment: The drive mechanism drives the drive disc to rotate in an orientation, and through the guide sliding structure, it drives several tensioning parts to move centripetally to the storage state. Then, the second rotary pressing cylinder on the base body continues to operate, so that the second pressure block always presses down to position the flange of the lower thin-walled cylinder. At the same time, the first rotary pressing cylinder drives the first pressure block to release the pressing effect on the pressure plate and removes the pressure plate, releasing the pressure plate from pressing the upper end of the upper thin-walled cylinder. Then, the rotary disc assembly is rotated, so that the rotary disc assembly drives several tensioning parts to rotate at a predetermined angle until several tensioning parts correspond one-to-one with the remaining weld seams between the upper and lower thin-walled cylinders after the first intermittent circumferential welding, completing the precise alignment of the welding station. S6: Tensioner reset and clamping: The drive mechanism drives the drive disc to reverse, and through the linkage of the guide sliding structure, drives several tensioners to perform centrifugal motion synchronously until the outer arc support of each tensioner is precisely pressed against the inner side of the corresponding weld seam. S7: Circumferential weld repair forming: Using a circumferential welding process, continuous repair welding is carried out on the remaining weld seam between the upper thin-walled cylinder and the lower thin-walled cylinder, so that the circumferential butt joint between the upper thin-walled cylinder and the lower thin-walled cylinder is completely welded, forming a complete and dense circumferential weld seam, and completing the overall assembly welding process.

[0023] By adopting the above technical solution, a two-stage welding process is employed: first, intermittent circumferential welding is performed, followed by final welding to complete the joint. The first intermittent circumferential welding, with equal intervals and arc lengths, initially fixes the butt joint of the upper and lower thin-walled cylinders, effectively suppressing thermal deformation caused by continuous welding. Combined with the positioning effect of the tensioning components, the strict coaxiality of the upper and lower cylinders is consistently maintained, preventing problems such as ellipticity and eccentricity in the thin-walled cylinders. Simultaneously, the welding area is covered by inert protective gas throughout the welding process, effectively isolating air and reducing defects such as oxidation and porosity at the weld site. Furthermore, the step-by-step welding reduces the heat input per weld, further improving weld quality. After the intermittent welding initially fixes the joint, the tooling position can be adjusted to precisely align the tensioning components with the remaining weld seams. During final welding, the tensioning components are reset and tightened again, ensuring a tight fit at all times and preventing warping or separation due to heat. Finally, continuous final welding forms a complete and dense circumferential welded joint, ensuring the stability of weld strength and effectively reducing overall welding defects, thus comprehensively improving the assembly welding quality of the thin-walled cylinders.

[0024] In summary, the present invention has the following beneficial effects: 1. This device utilizes a drive mechanism to rotate the drive disc, and through a guide sliding structure, drives several tensioning components to radially expand relative to the rotating disc assembly, and press against the joint between the upper and lower thin-walled cylinders. Then, the flanges of the upper and lower thin-walled cylinders are pressed down by the first and second rotary pressing cylinders respectively. At the same time, the vent plate is directly integrated into the outer wall of the arc-shaped outer support of the tensioning component. The vent plate is used to purge the joint between the upper and lower thin-walled cylinders with protective gas. It has the effects of high processing accuracy, convenient operation, and is conducive to improving processing efficiency and structural compactness, as well as improving production safety through automated processing.

[0025] 2. This device adopts a two-stage welding process: first, intermittent circumferential welding, and then supplementary welding to form the final shape. Intermittent circumferential welding can initially fix the joint and suppress thermal deformation. With the help of tensioning components, it ensures that the upper and lower cylinders are coaxial. Step-by-step welding reduces the heat input per welding cycle. Subsequent supplementary welding can accurately align the area to be welded. The tensioning components are reset and tightened to ensure that the joint fits. Finally, a complete and dense welded joint is formed, which effectively reduces defects and improves the quality of the weld assembly. Attached Figure Description

[0026] Figure 1 It is a thin-walled cylindrical structure in the prior art, which is formed by welding an upper thin-walled cylinder and a lower thin-walled cylinder together in a ring.

[0027] Figure 2 This is an overall structural diagram of the present invention.

[0028] Figure 3 This is a longitudinal sectional view of the present invention.

[0029] Figure 4 This is the present invention. Figure 3A magnified view of a portion of region A in the middle.

[0030] Figure 5 This is the present invention. Figure 3 A magnified view of a portion of region B in the middle.

[0031] Figure 6 This is a view showing the pressure plate separated from the base body of the present invention.

[0032] Figure 7 This is the present invention. Figure 6 A magnified view of a portion of region C.

[0033] Figure 8 This is the present invention. Figure 6 A magnified view of a portion of region D.

[0034] In the diagram: 1. Base body; 11. Second rotary pressing cylinder; 111. Second pressing block; 12. Second drive motor; 121. Second drive gear; 2. Rotary disk assembly; 21. Rotary table; 211. First rotary pressing cylinder; 2111. First pressing block; 212. Slider; 2121. Slide groove; 213. First drive motor; 2131. First drive gear; 22. Rotating base; 221. Second external gear ring; 222. Rotating shaft; 2221. Second bearing; 22 3. Bearing spacer; 3. Drive disc; 31. Arc groove; 32. Step groove; 33. First external gear ring; 4. Tensioner; 41. Slide rod; 411. Guide post; 412. First bearing; 413. Slide rail; 42. Arc outer support; 421. Annular groove; 422. Airflow channel; 4221. Air inlet connector; 5. Pressure plate; 51. Clearance hole; 6. Vent plate; 61. Vent hole; 7. Thin-walled cylinder; 71. Upper thin-walled cylinder; 72. Lower thin-walled cylinder; 721. Flange. Detailed Implementation

[0035] The invention will now be further described with reference to the accompanying drawings.

[0036] An automatic welding fixture for thin-walled cylindrical circumferential welds, such as Figures 2-6As shown, the assembly includes a base body 1 and a rotating disk assembly 2 mounted on the base body 1. A drive disk 3 is rotatably mounted on the rotating disk assembly 2. Several tensioning members 4 are arranged in a circular array on the rotating disk assembly 2. Each tensioning member 4 includes a sliding rod portion 41 and an arc-shaped outer support portion 42. The sliding rod portions 41 are radially distributed along the rotating disk assembly 2. A guide sliding structure is provided between the end of the sliding rod portion 41 away from the arc-shaped outer support portion 42 and the drive disk 3. The rotating disk assembly 2 is also equipped with a drive mechanism that drives the drive disk 3 to rotate and drives the tensioning members 4 to perform centripetal or centrifugal motion relative to the rotating disk assembly 2 through the guide sliding structure. Several first rotating downward pressing cylinders 211 are provided on the rotating disk assembly 2. The output end of each first rotating downward pressing cylinder 211 is connected to a first pressing block 211. 1. A pressure plate 5 is floating on the rotating disk assembly 2. A first rotating pressing cylinder 211 drives a first pressing block 2111 to press down the pressure plate 5, so that the pressure plate 5 is pressed down and engaged with the upper thin-walled cylinder 71. Several second rotating pressing cylinders 11 are spaced apart along the circumference of the rotating disk assembly 2 on the base body 1. The output end of the second rotating pressing cylinder 11 is connected to a second pressing block 111. The second rotating pressing cylinder 11 is used to drive the second pressing block 111 to press down the flange 721. A vent plate 6 is embedded on the outer wall of the arc-shaped outer support part 42 away from the sliding rod part 41. Several vent holes 61 are opened on the outer wall of the vent plate 6. The vent holes 61 are used to provide gas protection for the weld during welding. The air inlet end of the vent plate 6 is connected to a protective gas supply device. In this embodiment, the protective gas is argon.

[0037] like Figures 4-8As shown, the outer wall of the arc-shaped outer support 42 has an annular groove 421 along its length. The vent plate 6 is embedded in the annular groove 421. The arc-shaped outer support 42 has an airflow channel 422 that connects to the annular groove 421. The air inlet end of the airflow channel 422 is connected to an air inlet connector 4221, and the air outlet end of the airflow channel 422 connects to the vent plate 6. This allows the vent plate 6 to be semi-concealed and embedded in the outer wall of the arc-shaped outer support 42, preventing the vent plate 6 from contacting the upper thin-walled cylinder 71 or the lower thin-walled cylinder 72. Direct contact occurs, ensuring that the protective gas ejected from the vent holes 61 of the vent plate 6 always acts on the joint between the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72 to achieve inert gas protection; the tensioning member 4 is slidably mounted on the rotating disk assembly 2, and the guiding sliding structure includes a guide post 411 and an arc-shaped groove 31. The guide post 411 is fixedly connected to the end of the slide rod 41 away from the arc-shaped outer support 42, and a plurality of arc-shaped grooves 31 are arranged in a ring on the drive disk 3. The arc-shaped grooves 31 include The distance between the arc-shaped groove 31 and the center of the drive disk 3 gradually increases from the proximal end to the distal end, near the center of the drive disk 3. The guide post 411 guides and cooperates with the arc-shaped groove 31. Since the tensioning member 4 is slidably mounted on the rotating disk assembly 2, the tensioning member 4 can perform centripetal or centrifugal motion when the drive disk 3 rotates forward or reverse by utilizing the guiding effect of multiple arc-shaped grooves 31 inclined along the drive disk 3 and the corresponding guide post 411. The end of the guide post 411 away from the slide rod part 41 is provided with a first bearing 412. The drive disk 3 has an opening on the surface of the arc-shaped groove 31 that connects to a stepped groove 32. The first bearing 412 is rolled in the stepped groove 32. The first bearing 412 and the stepped groove 32 roll and cooperate, changing the sliding friction between the guide post 411 and the arc-shaped groove 31 to the rolling friction between the first bearing 412 and the stepped groove 32, thereby improving the smoothness of the sliding of the tensioning member 4 relative to the drive disk 3.

[0038] like Figures 6-8 As shown, one end of the sliding rod 41 is connected to the center of the arc-shaped outer support 42, making the tensioning member 4 have a T-shaped symmetrical structure. This makes the axis of the sliding rod 41 coincide with the center of symmetry of the arc-shaped outer support 42, providing uniform support force for the arc-shaped outer support 42. This ensures that the stress distribution of the arc-shaped outer support 42 on both sides of the sliding part is uniform and consistent, effectively avoiding the problem of deformation caused by uneven force on one side of the arc-shaped outer support 42. The bottom of the sliding rod 41 is fixed with a slide rail 413 along the length direction. Several sliders 212 are arranged in a ring on the rotating disk assembly 2. The sliders 212 are spaced apart around the circumference of the rotating disk assembly 2. The sliders 212 have grooves 2121 corresponding to the slide rail 413. The slide rail 413 and the groove 2121 guide each other, allowing the sliding rod 41 to slide smoothly in the radial direction relative to the rotating disk assembly 2, improving the consistency of the sliding direction of the tensioning member 4 relative to the rotating disk assembly 2.

[0039] like Figures 2-6As shown, the drive mechanism includes a first drive motor 213 and a first drive gear 2131 connected to the power output end of the first drive motor 213. A first external gear ring 33 is provided on the outer wall of the drive disc 3 corresponding to the first drive gear 2131. The first drive gear 2131 meshes with the first external gear ring 33. The first drive motor 213 drives the first drive gear 2131 to rotate, and the first drive gear 2131 then drives the drive disc 3 to rotate forward or backward through the first external gear ring 33. The pressure plate 5 presses the upper thin-walled cylinder 71 against the lower thin-walled cylinder 72, pressing... Plate 5 has a clearance hole 51 corresponding to the first pressure block 2111. The first rotary pressing cylinder 211 is used to drive the first pressure block 2111 to rotate and switch between the clearance position and the stop position relative to the clearance hole 51. The pressure plate 5 can realize the overall pressing and positioning of the upper thin-walled cylinder 71, ensuring the coaxiality and end face fit between the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72. When the first rotary pressing cylinder 211 drives the first pressure block 2111 to rotate into the clearance hole 51, the pressure plate 5 can be freely picked up and put in, which is convenient for loading, unloading and pre-placing of workpieces, and greatly improves assembly efficiency.

[0040] like Figures 3-7 As shown, the rotating disk assembly 2 includes a rotating platform 21 and a rotating base 22 concentrically connected to the rotating platform 21. A second external gear ring 221 is coaxially fixed to the outside of the rotating base 22. The rotating base 22 is rotatably connected to the middle of the base body 1. The base body 1 is equipped with a second drive motor 12. The power output end of the second drive motor 12 is connected to a second drive gear 121. The second drive gear 121 meshes with the second external gear ring 221. The second drive motor 12 drives the rotating base 22 and the rotating platform 21 to rotate coaxially through gear meshing, which can drive the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72 to rotate continuously. With the help of a fixed welding torch, the entire circumferential weld can be continuously welded in one go, avoiding joint defects caused by segmented welding, improving the weld integrity and appearance quality, and the second drive gear... The gear 121 meshes with the second external gear ring 221 for transmission, with accurate transmission ratio and high rotational precision. This effectively controls the stability of rotational speed, avoids workpiece swaying and eccentricity, ensures stable gap between the welding torch and the weld, and significantly improves the welding quality and consistency of the circumferential weld. The top of the rotating base 22 is fixed with a rotating shaft 222, and the drive disc 3 is rotatably connected to the rotating shaft 222. At least two second bearings 2221 are connected between the drive disc 3 and the rotating shaft 222. Adjacent second bearings 2221 are separated by bearing spacers 223. The drive disc 3 is supported and rotated by the rotating shaft 222 and at least two second bearings 2221. Multi-point support effectively improves radial load-bearing capacity and anti-overturning capacity, ensuring that the drive disc 3 rotates without jamming or swaying, and ensuring smooth operation when driving each tensioning component 4 to move radially synchronously.

[0041] The basic working principle of this invention is as follows: First, a driving mechanism drives several tensioning members 4 to move centripetally relative to the rotating disk assembly 2 to a retracted state. Then, the lower thin-walled cylinder 72 and the upper thin-walled cylinder 71 are stacked sequentially on the base body 1, so that the lower thin-walled cylinder 72 and the upper thin-walled cylinder 71 are fitted outside the rotating disk assembly 2. Then, the driving mechanism drives several tensioning members 4 to move centrifugally to an unfolded state, so that the arc-shaped outer support portion 42 of the tensioning member 4 abuts against the joint between the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72, ensuring that the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72 remain highly concentric in the vertical direction. Then, several second rotating downward pressing cylinders 11 on the base body 1 drive the second pressing block 111 to press down the flange 721 of the lower thin-walled cylinder 72, thereby ensuring that the bottom of the lower thin-walled cylinder 72 is always tightly fitted with the upper end face of the base body 1, so that the height of each point on the circumference of the lower thin-walled cylinder 72 remains consistent. Several first rotating pressing cylinders 211 on the rotating disk assembly 2 drive the first pressing block 2111 to press down the upper thin-walled cylinder 71, ensuring that the contact surfaces between the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72 are tightly fitted. Finally, the joint between the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72 is welded by a ring welding process. During the welding process, the protective gas supply device provides inert protective gas to the vent plate 6, and ensures that the inert protective gas ejected from the vent holes 61 of the vent plate 6 can always act between the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72 to achieve inert gas protection, reduce welding defects between the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72. In addition, the vent plate 6 of this device is directly integrated into the tensioning member 4, which improves the structural compactness and ease of operation of the device. This invention has the effects of high processing accuracy, convenient operation, and is conducive to improving processing efficiency, structural compactness, automated processing and improved production safety.

[0042] A welding method for an automatic assembly welding fixture for thin-walled cylindrical circumferential welds includes the following steps: S1: Tooling pre-adjustment and workpiece loading: The drive mechanism drives several tensioning parts 4 to move centripetally relative to the rotating disk assembly 2 to the storage state. Then, the lower thin-walled cylinder 72 and the upper thin-walled cylinder 71 are coaxially stacked on the base body 1 in sequence, so that the lower thin-walled cylinder 72 and the upper thin-walled cylinder 71 are coaxially sleeved on the outside of the rotating disk assembly 2 in the vertical direction, thus completing the initial positioning of the workpiece. S2: Workpiece clamping and fixing: Control the drive mechanism to reverse the action, drive several tensioning parts 4 to perform centrifugal expansion motion to the unfolded working state, so that the arc-shaped outer support part 42 at the end of each tensioning part 4 synchronously abuts against the inner side of the circumferential joint formed by the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72. Through the synchronous outer support action of multiple sets of tensioning parts 4, it is ensured that the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72 remain strictly coaxial in the vertical direction, so as to achieve uniform calibration of the circumferential gap of the joint. S3: Workpiece clamping and fixing: Several second rotary pressing cylinders 11 on the base body 1 drive the second pressing blocks 111 to press down the flange 721 of the thin-walled cylinder 72, so that the bottom end face of the thin-walled cylinder 72 is tightly fitted with the upper end face of the base body 1, so that the height and level of each point in the circumferential direction of the thin-walled cylinder 72 are consistent. At the same time, several first rotary pressing cylinders 211 on the rotating disk assembly 2 drive each first pressing block 2111 to press down and abut against the corresponding part of the upper end of the thin-walled cylinder 71, pressing the mating surface of the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72. S4: First Intermittent Circumferential Welding: Using a circumferential welding process, the circumferential butt joint between the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72 is subjected to circumferential intermittent welding with equal intervals and equal arc lengths; throughout the welding operation, the protective gas supply device is activated, and inert protective gas is continuously supplied to the ventilation plate 6 through the device. The ventilation plate 6 delivers the inert protective gas continuously and evenly to the welding area of ​​the circumferential butt joint through the pre-set ventilation holes 61 on the plate body, isolating air and forming an inert protective atmosphere; S5: Welding station adjustment: The drive mechanism drives the drive disk 3 to rotate in an orientation, and through the guide sliding structure, drives several tensioning parts 4 to move centripetally to the storage state. Then, the second rotating pressing cylinder 11 on the base body 1 continues to operate, so that the second pressing block 111 always presses down to position the flange 721 of the lower thin-walled cylinder 72. At the same time, the first rotating pressing cylinder 211 drives the first pressing block 2111 to release the pressing effect on the pressure plate 5 and remove the pressure plate 5, releasing the pressure plate 5 from pressing the upper end of the upper thin-walled cylinder 71. Then, the rotating disk assembly 2 is rotated, so that the rotating disk assembly 2 drives several tensioning parts 4 to rotate at a predetermined angle until several tensioning parts 4 correspond one-to-one with the remaining weld seams between the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72 after the first intermittent circumferential welding, thus completing the precise alignment of the welding station. S6: Tensioner reset and clamping: The drive mechanism drives the drive disk 3 to reverse, and through the linkage of the guide sliding structure, drives several tensioners 4 to perform centrifugal motion synchronously until the outer arc support 42 of each tensioner 4 is precisely pressed against the inner side of the corresponding weld seam. S7: Circumferential weld repair forming: Using a circumferential welding process, the remaining weld seam between the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72 is continuously repaired by welding, so that the circumferential butt joint between the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72 is completely welded, forming a complete and dense circumferential weld seam, and completing the overall assembly welding process.

[0043] This device employs a two-stage welding process: first, intermittent circumferential welding, followed by final welding to complete the weld. The first stage involves intermittent circumferential welding with equal intervals and arc lengths to initially fix the butt joint between the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72. This effectively suppresses thermal deformation caused by continuous welding. Combined with the positioning function of the tensioner 4, it ensures strict coaxiality of the upper and lower cylinders, preventing problems such as ellipticity or eccentricity in the thin-walled cylinder 7. Simultaneously, the welding area is covered by an inert protective gas throughout the welding process, effectively isolating air and reducing defects such as oxidation and porosity at the weld. Furthermore, the step-by-step welding reduces heat input per weld, further improving weld quality. After the intermittent welding initially fixes the joint, the tensioner 4 can be precisely aligned by adjusting the tooling position. For the remaining weld seams, the tensioning element 4 is reset and tightened again during the repair welding process to ensure that the joint is always tightly fitted and will not warp or separate due to heat. Finally, a complete and dense circumferential welded joint is formed through continuous repair welding, which not only ensures the stability of the welding strength, but also effectively reduces the overall welding defects and comprehensively improves the welding quality of the thin-walled cylinder 7. In addition, the intermittent weld points formed after the first intermittent circumferential weld can fix the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72. Therefore, after removing the pressure plate 5, the coaxiality between the upper thin-walled cylinder 71 and the lower thin-walled cylinder 72 will not change. This allows for precise processing of the circumferential weld repair without the pressure plate 5 during the subsequent circumferential weld repair process.

[0044] The above description is only a preferred embodiment of the present invention. Therefore, all equivalent changes or modifications made to the structure, features and principles described in the claims of this patent application are included in the scope of this patent application.

Claims

1. An automatic welding fixture for thin-walled cylindrical circumferential welds, comprising a base body (1) and a rotating disk assembly (2) disposed on the base body (1), characterized in that: The rotating disk assembly (2) is provided with a drive disk (3) rotatably mounted on it. The rotating disk assembly (2) is provided with a plurality of tensioning members (4) arranged in a ring. Each tensioning member (4) includes a sliding rod part (41) and an arc-shaped outer support part (42). The plurality of sliding rod parts (41) are distributed radially along the rotating disk assembly (2). A guide sliding structure is provided between the end of the sliding rod part (41) away from the arc-shaped outer support part (42) and the drive disk (3). The rotating disk assembly (2) is also provided with a drive mechanism. The drive mechanism drives the drive disk (3) to rotate and drives the plurality of tensioning members (4) to perform centripetal or centrifugal motion relative to the rotating disk assembly (2) through the guide sliding structure. The rotating disk assembly (2) is provided with a plurality of first rotating pressing cylinders (211). The output end of the first rotating pressing cylinder (211) is connected to a first pressing block (2111). A pressing plate (5) is floating on the rotating disk assembly (2). The first rotating pressing cylinder (211) drives the first pressing block (2111) to press down the pressing plate (5), so that the pressing plate (5) is pressed down and engaged with the upper thin-walled cylinder (71). The base body (1) is provided with a plurality of second rotary pressing cylinders (11) spaced around the circumference of the rotating disk assembly (2). The output end of the second rotary pressing cylinder (11) is connected to a second pressing block (111). The second rotary pressing cylinder (11) is used to drive the second pressing block (111) to press down the flange (721). A vent plate (6) is embedded on the outer wall of the arc-shaped outer support (42) away from the slide bar (41). The outer wall of the vent plate (6) is provided with several vent holes (61). The vent holes (61) are used to provide gas protection for the weld during welding. The air inlet end of the vent plate (6) is connected to a protective gas supply device.

2. The automatic welding fixture for thin-walled cylindrical circumferential welds according to claim 1, characterized in that: The outer wall of the arc-shaped outer support (42) is provided with an annular groove (421) along the length direction. The vent plate (6) is embedded in the annular groove (421). The arc-shaped outer support (42) is provided with an airflow channel (422) that connects to the annular groove (421). The air inlet end of the airflow channel (422) is connected to an air inlet connector (4221). The air outlet end of the airflow channel (422) is connected to the vent plate (6).

3. The automatic welding fixture for thin-walled cylindrical circumferential welds according to claim 1, characterized in that: The tensioning member (4) is slidably disposed on the rotating disk assembly (2). The guide sliding structure includes a guide post (411) and an arc groove (31). The guide post (411) is fixedly connected to one end of the slide rod (41) away from the arc outer support (42). A plurality of arc grooves (31) are arranged in a ring on the drive disk (3). The arc groove (31) includes a proximal end close to the center of the drive disk (3) and a distal end away from the center of the drive disk (3). The distance between the arc groove (31) and the center of the drive disk (3) gradually increases from the proximal end to the distal end. The guide post (411) and the arc groove (31) guide and cooperate.

4. The automatic welding fixture for thin-walled cylindrical circumferential welds according to claim 3, characterized in that: The guide post (411) is provided with a first bearing (412) at one end away from the slide bar (41), and the drive disk (3) is provided with a stepped groove (32) in the surface of the arc groove (31), and the first bearing (412) is rolled in the stepped groove (32).

5. The automatic welding fixture for thin-walled cylindrical circumferential welds according to claim 1, characterized in that: One end of the slide bar (41) is connected to the center of the arc-shaped outer support (42), so that the tensioning member (4) has a T-shaped symmetrical structure.

6. The automatic welding fixture for thin-walled cylindrical circumferential welds according to claim 1, characterized in that: The bottom of the slide rod (41) is fixed with a slide rail (413) along the length direction. The rotating disk assembly (2) has a plurality of sliders (212) arranged in a ring. The sliders (212) are spaced apart around the circumference of the rotating disk assembly (2). The sliders (212) have grooves (2121) corresponding to the slide rails (413). The slide rails (413) and the grooves (2121) are guided and engaged.

7. The automatic welding fixture for thin-walled cylindrical circumferential welds according to claim 1, characterized in that: The drive mechanism includes a first drive motor (213) and a first drive gear (2131) connected to the power output end of the first drive motor (213). The outer wall of the drive disk (3) is provided with a first external gear ring (33) corresponding to the first drive gear (2131). The first drive gear (2131) meshes with the first external gear ring (33).

8. The automatic welding fixture for thin-walled cylindrical circumferential welds according to claim 1, characterized in that: The pressure plate (5) presses the upper thin-walled cylinder (71) against the lower thin-walled cylinder (72). The pressure plate (5) has a clearance hole (51) corresponding to the first pressure block (2111). The first rotating pressing cylinder (211) drives the first pressure block (2111) to rotate and switch between the clearance position and the stop position relative to the clearance hole (51).

9. The automatic welding fixture for thin-walled cylindrical circumferential welds according to claim 1, characterized in that: The rotating disk assembly (2) includes a rotating platform (21) and a rotating base (22) concentrically connected to the rotating platform (21). A second external gear ring (221) is coaxially fixed outside the rotating base (22). The rotating base (22) is rotatably connected to the middle part of the base body (1). The base body (1) is provided with a second drive motor (12). The power output end of the second drive motor (12) is connected to a second drive gear (121). The second drive gear (121) meshes with the second external gear ring (221).

10. A welding method for an automatic assembly welding fixture for thin-walled cylindrical circumferential welds, characterized in that, Includes the following steps: S1: Tooling pre-adjustment and workpiece loading: The drive mechanism drives several tensioning parts (4) to move centripetally relative to the rotating disk assembly (2) to the storage state. Then, the lower thin-walled cylinder (72) and the upper thin-walled cylinder (71) are coaxially stacked on the base body (1) in sequence, so that the lower thin-walled cylinder (72) and the upper thin-walled cylinder (71) are coaxially sleeved on the outside of the rotating disk assembly (2) in the vertical direction, thus completing the initial positioning of the workpiece. S2: Workpiece clamping and fixing: Control the drive mechanism to reverse the action, drive several tensioning parts (4) to perform centrifugal expansion motion to unfold working state, so that the arc-shaped outer support part (42) at the end of each tensioning part (4) synchronously abuts against the inner side of the circumferential joint formed by the upper thin-walled cylinder (71) and the lower thin-walled cylinder (72). Through the synchronous outer support action of multiple sets of tensioning parts (4), ensure that the upper thin-walled cylinder (71) and the lower thin-walled cylinder (72) maintain strict coaxiality in the vertical direction, and realize uniform calibration of the circumferential gap of the joint. S3: Workpiece clamping and fixing: Several second rotary pressing cylinders (11) on the base body (1) drive the second pressing block (111) to press down the flange (721) of the thin-walled cylinder (72), so that the bottom end face of the thin-walled cylinder (72) is tightly fitted with the upper end face of the base body (1), so that the height and level of each point on the circumferential side of the thin-walled cylinder (72) are consistent. At the same time, several first rotary pressing cylinders (211) on the rotating disk assembly (2) drive each first pressing block (2111) to press down against the corresponding part of the upper end of the thin-walled cylinder (71), and press the mating surface of the upper thin-walled cylinder (71) and the lower thin-walled cylinder (72). S4: First intermittent circumferential welding: Using the circumferential welding process, the circumferential butt joint between the upper thin-walled cylinder (71) and the lower thin-walled cylinder (72) is subjected to circumferential intermittent welding with equal intervals and equal arc lengths; throughout the welding operation, the protective gas supply device is activated, and inert protective gas is continuously supplied to the ventilation plate (6) through the device. The ventilation plate (6) continuously delivers inert protective gas through the pre-set ventilation holes (61) on the plate body and evenly covers the welding area of ​​the circumferential butt joint, isolating air and forming an inert protective atmosphere; S5: Welding station adjustment: The drive mechanism drives the drive disk (3) to rotate in an orientation, and through the guide sliding structure, drives several tensioning parts (4) to move centripetally to the storage state. Then, the second rotary pressing cylinder (11) on the base body (1) continues to operate, so that the second pressure block (111) always presses down to position the flange (721) of the lower thin-walled cylinder (72). At the same time, the first rotary pressing cylinder (211) drives the first pressure block (2111) to release the pressing effect on the pressure plate (5), and removes the pressure plate (5), releasing the pressure plate (5) from pressing the upper end of the upper thin-walled cylinder (71). Then, the rotary disk assembly (2) is rotated, so that the rotary disk assembly (2) drives several tensioning parts (4) to rotate at a predetermined angle until several tensioning parts (4) correspond one-to-one with the remaining weld seams between the upper thin-walled cylinder (71) and the lower thin-walled cylinder (72) after the first intermittent circumferential welding, thus completing the precise alignment of the welding station. S6: Tensioner reset and clamping: The drive mechanism drives the drive disk (3) to reverse, and through the linkage of the guide sliding structure, drives several tensioners (4) to perform centrifugal motion synchronously until the arc-shaped outer support (42) of each tensioner (4) is precisely pressed against the inner side of the corresponding weld seam. S7: Circumferential weld repair forming: Using the circumferential welding process, the remaining weld seam between the upper thin-walled cylinder (71) and the lower thin-walled cylinder (72) is continuously repaired by welding, so that the circumferential butt joint between the upper thin-walled cylinder (71) and the lower thin-walled cylinder (72) is completely welded, forming a complete and dense circumferential weld seam, and completing the overall assembly welding process.

Images