Electron beam welding method for automatic assembly

Abstract

The invention relates to an automatic assembly electron beam welding method, belongs to the technical field of welding, and solves the problems that a traditional manual assembly mode adopted in the existing electron beam welding field is low in efficiency and poor in consistency, and the welding quality seriously depends on the level of an operator. According to the method, the special grabbing tools are installed on the to-be-welded workpieces correspondingly, the assembling robot and the automatic assembling tool are adopted to complete automatic assembling of the to-be-welded workpieces and positioning and clamping before welding, accurate and reliable automatic assembling of the to-be-welded workpieces is achieved, an electron beam welding production line for automatic assembling is further integrated, and the production efficiency is improved. The full-process automatic production from delivery of workpieces to be welded in a part state to automatic completion of laser cleaning of welding seams, automatic assembly of parts, welding seam quality detection and positioning welding to completion of welding and offline is realized, and the welding efficiency, the welding qualification rate and the utilization rate of electron beam equipment are effectively improved.

Description

Technical Field

[0001] The present invention relates to the field of welding technology, and in particular to an electron beam welding method for automatic assembly. Background Art

[0002] Electron beam welding technology is mainly applied to product or industrial fields with high quality or productivity requirements. Electron beam welding is one of the most mature high-energy beam processing methods at present. Since more stringent process requirements are faced in using electron beam welding, the process of electron beam welding is relatively complex, involving processes such as material transfer, pre-welding surface cleaning, assembly quality inspection, positioning welding, and electron beam welding. Especially before welding, complex welding processes and equipment are required to complete the pre-welding assembly and welding shaping of products. At present, in the field of electron beam welding, the pre-welding processes still mainly rely on manual operation or cooperation with single-machine equipment, with low efficiency, high cost, poor consistency, and the welding quality highly depending on the operator's level, which can neither meet the requirements of mass production nor conform to the development trend of intelligent and flexible equipment manufacturing. Summary of the Invention

[0003] In view of the above analysis, the embodiments of the present invention aim to provide an electron beam welding method for automatic assembly to solve the problems of low efficiency, poor consistency, and the welding quality highly depending on the operator's level in the traditional manual assembly method in the existing electron beam welding field.

[0004] The object of the present invention is mainly achieved through the following technical solutions:

[0005] An electron beam welding method for automatic assembly includes the following steps:

[0006] Step S1: Take out the workpiece to be welded from the warehouse and transfer it to the laser cleaning station by the logistics system;

[0007] Step S2: Complete the pre-welding cleaning of the weld of the workpiece to be welded and transfer it to the automatic assembly station by the logistics system;

[0008] Step S3: Complete the automatic assembly and pre-welding positioning and clamping of the workpiece to be welded and transfer it to the pre-adjustment and positioning welding station by the logistics system;

[0009] Step S4: Complete the weld quality inspection and positioning welding and transfer it to the electron beam welding station by the logistics system;

[0010] Step S5: Complete the electron beam welding of the workpiece to be welded.

[0011] Further, step S3 includes the following sub-steps:

[0012] S310: Select a grasping and positioning tooling and complete the assembly of the grasping and positioning tooling;

[0013] S320: Install a vision positioning block on the grasping and positioning tooling.

[0014] S330: Install the grasping and positioning tooling on the workpieces to be welded respectively.

[0015] S340: Complete the automatic assembly of the workpieces to be welded and perform pre-welding positioning and clamping on the workpieces to be welded through the automatic assembly tooling.

[0016] S350: Transfer the assembled parts to the pre-adjustment and tack-welding station by the logistics system.

[0017] Further, the grasping and positioning tooling is a bolt-type grasping and positioning tooling; sub-step S330 includes the following sub-steps:

[0018] S331-1: Align and tighten the connecting and fixing bolts on the bolt-type grasping and positioning tooling with the positioning holes of the workpieces to be welded.

[0019] S332-1: Tighten the locking screws on the bolt-type grasping and positioning tooling.

[0020] Further, the grasping and positioning tooling is a clamping-type grasping and positioning tooling; sub-step S330 includes the following sub-steps:

[0021] S331-2: Place the workpiece to be welded on the clamping unit of the clamping-type grasping and positioning tooling.

[0022] S332-2: Align the docking part on the workpiece to be welded with the docking unit on the clamping-type grasping and positioning tooling.

[0023] S333-2: Operate the locking structure on the clamping unit to complete the installation of the clamping-type grasping and positioning tooling.

[0024] Further, the grasping and positioning tooling includes a bolt-type grasping and positioning tooling and a clamping-type grasping and positioning tooling; sub-step S330 includes the following sub-steps:

[0025] S331-3: Align and tighten the connecting and fixing bolts on the bolt-type grasping and positioning tooling with the positioning holes of one of the workpieces to be welded.

[0026] S332-3: Tighten the locking screws on the bolt-type grasping and positioning tooling to complete the installation of the bolt-type grasping and positioning tooling.

[0027] S333-3: Place the other workpiece to be welded on the clamping unit of the clamping-type grasping and positioning tooling.

[0028] S334-3: Align the docking part on the workpiece to be welded with the docking unit on the clamping-type grasping and positioning tooling.

[0029] S335 - 3: Operate the locking structure on the clamping unit to complete the installation of the clamping - type grasping and positioning tooling.

[0030] Furthermore, sub - step S340 also includes the following sub - steps:

[0031] S341: The automatic assembly robot first takes a photo of the vision - positioning block of the workpiece through the vision system to obtain the grasping point.

[0032] S342: The automatic assembly robot grasps the first workpiece to be welded, installs the first workpiece to be welded on the automatic assembly tooling, and releases the robot gripper.

[0033] S343: The automatic assembly robot grasps the second workpiece to be welded, docks the second workpiece to be welded with the first workpiece to be welded, installs them on the automatic assembly tooling, and releases the robot gripper.

[0034] S344: The locking mechanism of the automatic assembly tooling locks the workpiece to be welded.

[0035] Furthermore, in sub - steps S342 and S343, the spherical block on the robot gripper of the automatic assembly robot docks with the grasping and positioning guide hole on the grasping and positioning tooling for positioning and grasping.

[0036] Furthermore, steps S1 to S2 adopt an AGV transportation device, and the transfer of the workpiece to be welded is completed by docking the AGV transfer tray with the docking station of the next station.

[0037] Furthermore, step S3 adopts an AGV transfer device, and the transfer of the assembled workpiece is completed by docking the base of the automatic assembly tooling with the docking station of the next station.

[0038] Furthermore, step S4 includes the following sub - steps:

[0039] S410: Use a laser 3D camera to detect the assembly gap of the workpiece.

[0040] S420: If the detected docking gap is more than 0.1 mm, an alarm is given for unqualified, and manual pre - adjustment of the docking gap is carried out. If the detected docking gap < 0.1 mm, the next process is directly carried out.

[0041] S430: The collaborative - arm robot performs laser positioning welding on the qualified area to be welded.

[0042] S440: The logistics system transports the assembled parts to the electron - beam welding station.

[0043] On the other hand, the present invention also provides an electron beam welding production line for automatic assembly, which is used to implement the above-mentioned electron beam welding method for automatic assembly; the electron beam welding production line for automatic assembly includes a laser cleaning unit, an automatic assembly unit, a pre-adjustment and positioning welding unit, an electron beam welding unit, and an AGV logistics system.

[0044] Further, the laser cleaning unit includes a gantry truss, a collaborative arm robot, a laser cleaning head, a laser cleaning machine, and a workpiece placement table to be welded.

[0045] Further, the automatic assembly unit includes an automatic assembly robot, an automatic assembly tooling, an automatic assembly tooling docking station, a workpiece docking station to be welded, and a tooling storage table.

[0046] Further, the end of the assembly robot of the automatic assembly robot includes a robot gripper, a vision system, and a force control system; a spherical block is arranged on the robot gripper.

[0047] Further, the automatic assembly tooling includes a tooling base, a fixed base, a moving base, a first clamping mechanism, a second clamping mechanism, and a tooling power-on device.

[0048] Further, the pre-adjustment and positioning welding unit includes a gantry truss, a collaborative arm robot, a laser 3D camera, a laser positioning welding machine, a tooling rotation device, and a tooling automatic power-on device.

[0049] Further, the electron beam welding unit includes an electron beam welding device, an electron beam automatic loading and unloading gantry robot, and a tooling positioning buffer docking station.

[0050] Further, the AGV logistics system includes a small AGV for transporting workpieces to be welded, a large AGV for transporting tooling, a small AGV transfer tray, and a scheduling system.

[0051] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0052] (1) By installing a dedicated grasping and positioning tooling and a vision positioning block on the workpiece to be welded, the assembly robot can accurately position and grasp the workpiece to be welded, meeting the preconditions for automatic and precise assembly.

[0053] (2) By using a six-dimensional force control sensor and performing steps such as locking, pressing, and welding profiling of the workpiece to be welded by the automatic assembly tooling, the compliant docking of the workpiece to be welded is completed, realizing automatic assembly and clamping positioning before welding; reducing production costs and improving assembly quality, creating conditions for accurate, reliable, and efficient electron beam welding.

[0054] (3) By adopting the AGV intelligent transportation device and the method of docking and positioning the transfer tray or the automatic tooling base with the station docking station, the whole process automation from the outgoing of the workpiece to be welded in the form of parts to the automatic completion of laser cleaning of the weld seam, automatic assembly of parts, weld quality inspection and positioning welding until the completion of welding and offline is realized, effectively improving the welding efficiency, welding qualification rate and the utilization rate of the electron beam equipment.

[0055] In the present invention, the above technical solutions can also be combined with each other to achieve more preferred combination schemes. Other features and advantages of the present invention will be described in the following content, and some advantages can be made obvious from the specification or understood by implementing the present invention. The purpose and other advantages of the present invention can be achieved and obtained through the content specifically pointed out in the text and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] The drawings are only for the purpose of showing specific embodiments and are not considered as a limitation to the present invention. Throughout the drawings, the same reference signs denote the same components.

[0057] Figure 1 Flow chart of the electron beam welding method for automatic assembly in Specific Embodiment 1;

[0058] Figure 2 Flow chart of the automatic assembly in Specific Embodiment 1;

[0059] Figure 3 Structure schematic diagram of the workpiece tray and the workpiece docking station in Specific Embodiment 1;

[0060] Figure 4 Structure schematic diagram of the grasping and positioning tooling in Specific Embodiment 1;

[0061] Figure 5 Structure schematic diagram of the end of the assembly robot in Specific Embodiment 1;

[0062] Figure 6 Flow chart of the automatic assembly in Specific Embodiment 2;

[0063] Figure 7 Structure schematic diagram of the grasping and positioning tooling in Specific Embodiment 2;

[0064] Figure 8 Schematic diagram of the positioning block in Specific Embodiment 2;

[0065] Figure 9 Schematic diagram of the electron beam welding production line for automatic assembly in Specific Embodiment 3;

[0066] Figure 10 Structure schematic diagram of the automatic assembly unit in Specific Embodiment 3;

[0067] Reference Signs:

[0068] 1 - Bolt - type grasping and positioning tooling; 11 - First positioning block; 111 - First grasping and positioning hole; 112 - Second grasping and positioning hole; 12 - Second positioning block; 13 - Vision positioning block; 14 - Connecting and fixing bolt; 15 - Replaceable positioning sleeve; 16 - Locking screw; 2 - Band - type grasping and positioning tooling; 21 - First connecting rod; 22 - Second connecting rod; 23 - Third connecting rod; 24 - Holding ring; 25 - Band; 26 - Workpiece positioning block; 261 - Workpiece positioning groove; 27 - Locking structure; 3 - End of the assembly robot; 31 - Robot gripper; 311 - Spherical block; 32 - Vision system; 33 - Force - control system; 4 - Workpiece transfer station; 41 - Conical guide; 5 - Tray; 51 - Positioning structure; 6 - Workpiece to be welded; 7 - Laser cleaning unit; 8 - Automatic assembly unit; 81 - Automatic assembly robot; 82 - Automatic assembly tooling; 821 - Base; 822 - Fixed base; 823 - Moving base; 824 - First clamping mechanism; 825 - Second clamping mechanism; 826 - Tooling power - on device; 83 - Automatic assembly tooling transfer station; 84 - Workpiece to be welded transfer station; 85 - Tooling storage table; 9 - Pre - adjustment and tack - welding unit; 10 - Electron beam welding unit; 1001 - AGV logistics system. Detailed Embodiment

[0069] The following will specifically describe the preferred embodiments of the present invention in conjunction with the accompanying drawings. Among them, the accompanying drawings form a part of the present invention and are used together with the embodiments of the present invention to explain the principle of the present invention, rather than to limit the scope of the present invention.

[0070] Embodiment 1

[0071] A specific embodiment of the present invention, as Figure 1 shown, discloses an electron beam welding method for automatic assembly, realizing the full - process automation from the workpiece to be welded being taken out of the warehouse in a part state to automatically completing the laser cleaning of the weld seam, the automatic assembly of parts, the quality inspection and positioning welding of the weld seam, and finally the welded workpiece being taken offline. It mainly includes the following steps:

[0072] Step S1: Take out the workpiece to be welded from the warehouse and transfer it to the laser cleaning station by the logistics system.

[0073] Step S2: Complete the pre - welding cleaning of the weld seam of the workpiece to be welded and transfer it to the automatic assembly station by the logistics system;

[0074] Further, in steps S1 and S2, a small AGV transport cart is used, and the transfer of the workpiece to be welded is completed by docking the AGV transfer tray with the transfer station of the next station.

[0075] Specifically, as Figure 3As shown in the figure, in this embodiment, the assembly and welding of two cylindrical parts are taken as an example. In order to ensure the consistency of the workpiece gripping position during assembly, positioning structures such as positioning pins and positioning blocks 51 are arranged on the surface of the tray 5 to ensure the precise positioning of the workpiece on the tray 5. In addition, in the way of conical guiding 51, the position of the tray 5 remains unchanged when it descends to the workpiece docking station 4, so as to ensure the precise positioning of the tray 5 and the workpiece docking station 4. During laser cleaning, while the laser head of the laser cleaning equipment moves slowly along the weld of the workpiece to be welded 6, the laser head of the laser cleaning equipment is activated, and then the cleaning of the weld is completed.

[0076] Step S3: Complete the automatic assembly and docking positioning of the workpiece to be welded, and transfer it to the pre-adjustment and positioning welding station by the logistics system.

[0077] Further, as Figure 2 shown, step S3 further includes the following sub-steps:

[0078] S310: Select the gripping and positioning tooling and complete the assembly of the gripping and positioning tooling;

[0079] S320: Install the visual positioning block on the gripping and positioning tooling;

[0080] S330: Install the gripping and positioning tooling on the workpiece to be welded respectively;

[0081] S340: Complete the automatic assembly of the workpiece to be welded and implement pre-welding positioning and clamping of the workpiece to be welded through the automatic assembly tooling;

[0082] S350: Transfer the assembled parts to the pre-adjustment and positioning welding station by the logistics system.

[0083] Further, the gripping and positioning tooling is a bolt-type gripping and positioning tooling; sub-step S330 includes the following sub-steps:

[0084] S331: Align and tighten the connecting and fixing bolts on the bolt-type gripping and positioning tooling with the positioning holes of the workpiece to be welded;

[0085] S332: Tighten the locking screws on the bolt-type gripping and positioning tooling.

[0086] Specifically, as Figure 4As shown, in the current field of robotics, methods such as vacuum suction cups and opening / closing grippers are mainly used to directly grasp workpieces. In this embodiment, a method of installing a grasping and positioning tooling on the workpiece to be welded is adopted to achieve high-precision grasping, positioning, and assembly. Taking the case where the workpiece to be welded can be machined with mounting holes as an example, this embodiment uses a bolt connection method to connect the workpiece to be welded and the grasping and positioning tooling. First, the first positioning block 11 and the second positioning block 12 of the bolt-type grasping and positioning tooling 1 are assembled and connected by bolts, and then the T-shaped vision positioning block 13 for machine vision positioning is fixed on the first positioning block 11 through the positioning pin holes and screw connection holes on the T-shaped vision positioning block. Replaceable positioning sleeves 15 are installed at the ends of the first positioning block 11 and both ends of the second positioning block 12. The replaceable positioning sleeves 15 are fixed and disassembled from the positioning blocks through locking screws 14, facilitating the replacement of the new positioning sleeve assembly after wear caused by long-term use. When connecting to the workpiece to be welded 6, first, the connecting and fixing bolts 14 installed in the three replaceable positioning sleeves 15 are docked with the positioning holes on the workpiece to be welded and tightened, and then the locking screws 16 are tightened, thus completing the installation of the grasping and positioning tooling on the workpiece to be welded. In this embodiment, there are two workpieces to be welded, so the installation needs to be completed separately.

[0087] Furthermore, sub-step S340 further includes the following sub-steps:

[0088] S341: The automatic assembly robot first takes a photo of the vision positioning block of the workpiece through the vision system to obtain the grasping points;

[0089] Specifically, as Figure 5 shown, the end 3 of the automatic assembly robot includes a robot gripper 31, a vision system 32, and a force control system 33. The T-shaped vision positioning block 13 is fixedly installed on the grasping and positioning tooling 1 through bolts. The T-shaped vision positioning block 13 includes multiple rectangles, trapezoids, and irregular-shaped planes with different sizes, enabling the robot vision system 32 to position the grasping and positioning tooling 1 when taking photos of the T-shaped vision positioning block 13 from different orientations and distances, effectively solving the problem of inability to visually position arc-shaped workpieces.

[0090] S342: The automatic assembly robot grasps the first workpiece to be welded, fixedly installs the first workpiece to be welded on the automatic assembly tooling, and releases the robot gripper;

[0091] S343: The automatic assembly robot grasps the second workpiece to be welded, docks the second workpiece to be welded with the first workpiece to be welded, fixedly installs them on the automatic assembly tooling, and releases the robot gripper;

[0092] Further, in steps S342 and S343, the spherical block 311 on the automatic assembly robot gripper 31 is docked with the first grasping and positioning hole 111 and the second grasping and positioning hole 112 on the grasping and positioning tooling 1 to complete positioning and grasping.

[0093] Specifically, the robot gripper 31 includes a cylinder and a gripper. The gripper has functions of loosening and clamping, and a spherical block 311 with a guiding function is designed on the loosening and clamping structure. Correspondingly, the first positioning block 11 has two grasping and positioning guiding holes. The first grasping and positioning hole 111 is a circular guiding hole, and the second grasping and positioning hole 112 is an elliptical guiding hole. When the robot grasps the workpiece, the gripper opens, and the spherical block 311 at the fixed end of the gripper is docked with the grasping and positioning guiding holes on the first positioning block 11. After the docking is completed, the cylinder acts to move the spherical block 311 into the grasping and positioning guiding holes to achieve clamping. The elliptical second grasping and positioning hole 112 can compensate for the deviation between the spherical block 311 and the positioning guiding holes. In this embodiment, due to the method of guiding and positioning with the spherical block 311, it can not only realize the positioning and guiding of the workpiece during grasping, but also realize that the workpiece will not fall off during movement and flipping after clamping.

[0094] S344: Lock the automatic assembly tooling to complete the automatic assembly of the workpiece to be welded;

[0095] Specifically, the operation process of the automatic assembly tooling receives operation instructions through the interface of the power-on device to complete automatic assembly.

[0096] Further, in step S350, a large AGV transfer vehicle is used to complete the transfer of the assembled workpiece by docking the base of the automatic assembly tooling with the docking station of the next station.

[0097] Specifically, in this step, a large AGV transfer vehicle is used to transfer the automatic assembly tooling with the locked workpiece to be welded to the next station as a whole.

[0098] Step S4: Automatically complete weld quality inspection and positioning welding, and transfer to the electron beam welding station by the logistics system;

[0099] Further, step S4 includes the following sub-steps:

[0100] S410: Use a laser 3D camera to detect the assembly gap of the workpiece;

[0101] S420: If the detected docking gap is more than 0.1 mm, it is reported as unqualified and adjusted manually. If the detected docking gap < 0.1 mm, the next process is directly carried out;

[0102] S430: The collaborative arm robot performs laser positioning welding on the qualified area to be welded.

[0103] S440: The assembly is transported to the electron beam welding station by the logistics system.

[0104] Specifically, first, a laser 3D camera is used to detect the butt joint assembly gap of the assembled workpiece. A butt joint gap < 0.1 mm is considered qualified. If the detection is unqualified, an alarm is given and manual pre-adjustment of the butt joint gap is reminded. If the detection is qualified, the tack welding process starts. The collaborative arm robot carries a laser positioning welding torch through a quick-change disk and performs laser positioning welding on the qualified area to be welded.

[0105] Step S5: Complete the electron beam welding of the workpiece to be welded.

[0106] Specifically, the electron beam welding equipment realizes the positioning and rotation control of the tooling by setting a guiding cone on the platform and connecting it to the rotating shaft of the tooling through a positioner. Through a pre-programmed offline program, the platform and the tooling automatically enter the chamber for welding, and the welding is automatically ended when completed.

[0107] Embodiment 2

[0108] The second embodiment disclosed by the present invention, as Figure 6 shown, is different from Embodiment 1 in that the grasping and positioning tooling is a clamping type grasping and positioning tooling; sub-step S330 includes the following sub-steps:

[0109] S331-2: Place the workpiece to be welded on the clamping unit of the grasping and positioning tooling;

[0110] S332-2: Align the butt joint part on the workpiece to be welded with the butt joint unit on the grasping and positioning tooling;

[0111] S333-2: Operate the locking structure on the clamping unit to complete the installation of the grasping and positioning tooling.

[0112] Specifically, as Figure 7As shown in the figure, the clamping and grasping positioning tooling of this embodiment adopts a strap-type grasping and positioning tooling 2, which is used for the case where the workpiece to be welded is cylindrical and no mounting holes can be provided on the surface of the workpiece. The strap-type grasping and positioning tooling 2 includes a first connecting rod 21, a second connecting rod 22, a third connecting rod 23, a holding ring 24, a strap 25, a workpiece positioning block 26, and a locking structure 27. The two ends of the first connecting rod 21, the second connecting rod 22, and the third connecting rod 23 are respectively connected and fixed to the middle and both ends of the two holding rings 24; the clamping unit is provided with two straps 25. One ends of the two straps 25 are respectively fixed to both ends of the third connecting rod 23, and the other ends are respectively connected to both ends of the second connecting rod 22 through the locking structure 27. The holding ring 24, the strap 25, and the locking structure 27 form a clamping unit. When performing sub-step S330, first place the workpiece to be welded on the two straps of the clamping unit. After docking the docking part on the workpiece to be welded with the docking unit on the grasping and positioning tooling, operate the locking structure 27 to complete the installation of the strap-type grasping and positioning tooling 2. As Figure 8 shown, the docking unit on the strap-type grasping and positioning tooling 2 is the workpiece positioning block 26 installed at both ends of the two holding rings 24. The workpiece positioning block 26 is provided with a workpiece positioning groove 261. A positioning boss matching the workpiece positioning groove 261 is preset on the surface of the workpiece to be welded. Through the docking of the workpiece positioning groove 261 and the positioning boss, the precise positioning between the workpiece to be welded and the grasping and positioning tooling is completed. Similarly, since there are two welding workpieces, the steps of installing the clamping and grasping positioning tooling on the two welding workpieces need to be completed separately. In this embodiment, the grasping and positioning holes of the clamping and grasping positioning tooling are arranged on the first connecting rod.

[0113] It should be noted that according to the specific conditions of the workpiece to be welded and the automatic assembly tooling, bolt-type and clamping-type grasping and positioning toolings can be respectively selected on the two workpieces to be welded. Therefore, sub-step S330 includes the following sub-steps:

[0114] S331-3: Docking and tightening the connecting and fixing bolts on the bolt-type grasping and positioning tooling with the positioning holes of one of the welding workpieces;

[0115] S332-3: Tightening the locking screws on the bolt-type grasping and positioning tooling to complete the installation of the bolt-type grasping and positioning tooling.

[0116] S333-3: Placing the other welding workpiece on the clamping unit of the clamping-type grasping and positioning tooling;

[0117] S334-3: Docking the docking part on the welding workpiece with the docking unit on the clamping-type grasping and positioning tooling;

[0118] S335-3: Operating the locking structure on the clamping unit to complete the installation of the clamping-type grasping and positioning tooling.

[0119] Example 3

[0120] A specific embodiment of the present invention is, for example Figure 9 As shown, an electron beam welding production line for automatic assembly is used to implement the electron beam welding method for automatic assembly in Example 1 or Example 2. The electron beam welding production line for automatic assembly in this embodiment includes a laser cleaning unit 7, an automatic assembly unit 8, a pre-adjustment and positioning welding unit 9, an electron beam welding unit 10, and an AGV logistics system 1001.

[0121] Furthermore, the laser cleaning unit 7 includes a gantry truss, a collaborative arm robot, a laser cleaning head, a laser cleaning machine, and a workpiece placement table for welding.

[0122] Specifically, the gantry truss includes an X-axis, a Y-axis, and a Z-axis, and its movement range can effectively cover the movement area of the gantry truss. The collaborative arm robot is integrated at the end of the Z-axis of the gantry truss, and the laser cleaning head is integrated at the end of the collaborative arm robot. Two workpiece placement tables for welding are arranged in the area covered by the gantry truss.

[0123] Furthermore, the automatic assembly unit 8 includes an automatic assembly robot 81, an automatic assembly tooling 82, an automatic assembly tooling docking station 83, a workpiece docking station 84 for welding, and a tooling storage table 85.

[0124] Specifically, as Figure 10 shown, the automatic assembly tooling 82 is placed on the tooling storage docking station 83. The automatic assembly robot 81 is located in front of the tooling storage docking station 83. The workpiece docking station 84 for welding is located on one side of the automatic assembly robot 81, and the tooling storage table 85 is located on the other side of the automatic assembly robot 81. The automatic assembly robot 81 can rotate to grab the workpiece 6 to be welded on the workpiece docking station 84 for welding and the tooling on the tooling storage table 85. The tooling storage docking station 83 is provided with a conical guiding mechanism, which cooperates with the guiding hole at the bottom of the automatic assembly tooling to achieve accurate positioning.

[0125] Furthermore, the assembly robot end 3 of the automatic assembly robot 81 includes a robot gripper 31, a vision system 32, and a force control system 33; a spherical block 311 is arranged on the robot gripper 31.

[0126] Specifically, as Figure 5As shown in the figure, the robot gripper 31 includes a cylinder and a gripper. The gripper has the functions of loosening and clamping, and a spherical block 311 with a guiding function is arranged on the loosening and clamping structures. The robot gripper 31 can automatically grasp the workpiece 6 to be welded equipped with a grasping and positioning tooling. Different robot grippers 31 can also be selected according to different grasping and positioning toolings. At the same time, the end 3 of the assembly robot is also integrated with a vision system 32 and a force control system 33. The force control system 33 has a six-dimensional force control sensor system, which is integrated with the robot system to achieve compliant force control after vision-guided docking. When grasping and assembling workpieces, the docking angle can be adjusted in real time through the force sensor, so as to achieve compliant docking effects in common states such as pin and pinhole docking and cylindrical rabbet docking, and solve the problem of workpiece deformation caused by the robot directly completing the docking under normal circumstances.

[0127] Furthermore, the automatic assembly tooling 82 includes a tooling base 821, a fixed base 822, a moving base 823, a first clamping mechanism 824, a second clamping mechanism 825, and a tooling power-on device 826.

[0128] Specifically, as Figure 10 shown, the upper end of the automatic assembly tooling docking station 83 is provided with a conical guide. After the bottom of the tooling base 821 is docked with the conical guide, it is located on the automatic assembly tooling docking station 83. One side of the tooling base 821 is a fixed base 822, and the other side is a moving base 823. Before automatic assembly, first, two first clamping mechanisms 824 matching the workpiece 6 to be welded are installed on the tooling base 821. The automatic assembly robot 81 grasps the first workpiece 6 to be welded and installs the first workpiece 6 to be welded on the fixed base 822. The first clamping mechanism 824 on the same side is moved to the corresponding position to support the welding end of the first workpiece 6 to be welded. The automatic assembly robot 81 releases the gripper to complete the installation of the first workpiece 6 to be welded. Then, the automatic assembly robot 81 grasps the second workpiece 6 to be welded, docks the second workpiece 6 with the first workpiece 6 to be welded and ensures that the docking gap is in place. Then, the moving base 823 is moved towards the workpiece 6 to be welded and installed and clamped with the second workpiece 6 to be welded. Another first clamping mechanism 823 is moved to the corresponding position to support the welding end of the second workpiece 6 to be welded. Finally, the two second clamping mechanisms 825 are respectively connected to the two first clamping mechanisms 824 and locked and fixed to complete the automatic assembly of the workpiece 6 to be welded. The tooling power-on device 826 can receive operation instructions and cooperate with the automatic assembly robot 81 to complete the automatic assembly of the workpiece 6 to be welded and the locking of the automatic assembly tooling 82.

[0129] Furthermore, the pre-adjustment and tack welding unit 9 includes a gantry truss, a collaborative arm robot, a laser 3D camera, a laser positioning welder, a tooling rotation device, and a tooling automatic power-on device.

[0130] Specifically, a collaborative robot arm is integrated on the Z-axis of the gantry truss. Through a quick-change chuck mounted at the end of the collaborative robot arm, the laser 3D camera or the welding torch of the laser positioning welding machine can be quickly replaced.

[0131] Furthermore, the electron beam welding unit 10 includes an electron beam welding device, an electron beam automatic loading and unloading gantry robot, and a tooling positioning buffer transfer station.

[0132] Specifically, after the AGV logistics system 1001 transports the automatic assembly tooling 81 that has completed positioning welding to the electron beam welding station, it is placed on the tooling positioning buffer transfer station for secondary positioning, so as to facilitate the accurate grasping by the electron beam automatic loading and unloading gantry robot. The electron beam automatic loading and unloading gantry robot is equipped with a gripper matching the automatic assembly tooling 81. After grasping the automatic assembly tooling 81 on the tooling positioning buffer transfer station, it is positioned through the guiding cone of the tooling positioning buffer transfer station and placed on the platform of the electron beam welding device.

[0133] Furthermore, the AGV logistics system 1001 includes small AGVs for transporting workpieces to be welded, large AGVs for transporting tooling, small AGV transfer trays, and a scheduling system.

[0134] Specifically, the AGV logistics system 1001 completes the task planning of the AGVs through the scheduling system and transports the workpieces to be welded 6 and the automated assembly tooling 81 to the corresponding stations.

[0135] The electron beam welding production line of this embodiment is used for the electron beam welding method robot gripper for automated assembly in Embodiment 1 or Embodiment 2, realizing the automated assembly of the workpieces to be welded before welding. Through the transfer of the intelligent logistics system, all processes of electron beam welding are automated and integrated. It realizes that the electron beam welding production exits the warehouse in a part state, automatically completes pre-welding processes such as laser cleaning of the weld seam, automatic assembly of parts, weld quality inspection, and positioning welding, greatly improving the processing efficiency before welding, improving the welding quality, and increasing the utilization rate of electron beam equipment.

Claims

1. An electron beam welding method for automatic assembly, characterized in that, it includes the following steps: Step S1: Take out the workpiece to be welded and transfer it to the laser cleaning station by the logistics system; Step S2: Complete the pre-welding cleaning of the weld seam of the workpiece to be welded and transfer it to the automatic assembly station by the logistics system; Step S3: Complete the automatic assembly and pre-welding positioning and clamping of the workpiece to be welded and transfer it to the pre-adjustment and tack welding station by the logistics system; Step S4: Complete the weld quality inspection and tack welding and transfer it to the electron beam welding station by the logistics system; Step S5: Complete the electron beam welding of the workpiece to be welded.

2. The electron beam welding method for automatic assembly according to claim 1, characterized in that, the said Step S3 includes the following sub-steps: S310: Select the grasping and positioning tooling and complete the assembly of the grasping and positioning tooling; S320: Install the vision positioning block on the grasping and positioning tooling; S330: Install the grasping and positioning tooling on the workpiece to be welded respectively; S340: Complete the automatic assembly of the workpiece to be welded and implement the pre-welding positioning and clamping of the workpiece to be welded through the automatic assembly tooling; S350: The logistics system transfers the assembled parts to the pre-adjustment and tack welding station.

3. The electron beam welding method for automatic assembly according to claim 2, characterized in that, the said grasping and positioning tooling is a bolt-type grasping and positioning tooling; the sub-step S330 includes the following sub-steps: S331-1: Align and tighten the connecting and fixing bolts on the bolt-type grasping and positioning tooling with the positioning holes of the workpiece to be welded; S332-1: Tighten the locking screws on the bolt-type grasping and positioning tooling.

4. The electron beam welding method for automatic assembly according to claim 2, characterized in that, the said grasping and positioning tooling is a clamping-type grasping and positioning tooling; the sub-step S330 includes the following sub-steps: S331-2: Place the workpiece to be welded on the clamping unit of the clamping-type grasping and positioning tooling; S332-2: Align the docking part on the workpiece to be welded with the docking unit on the clamping-type grasping and positioning tooling; S333-2: Operate the locking structure on the clamping unit to complete the installation of the clamping-type grasping and positioning tooling.

5. The electron beam welding method for automatic assembly according to claim 2, characterized in that, the said sub-step S340 further includes the following sub-steps: S341: The automatic assembly robot first takes a photo of the vision positioning block of the workpiece through the vision system to obtain the grasping point; S342: The automatic assembly robot grasps the first workpiece to be welded, installs the first workpiece to be welded on the automatic assembly tooling, and releases the robot gripper; S343: The automatic assembly robot grasps the second workpiece to be welded, docks the second workpiece to be welded with the first workpiece to be welded, installs it on the automatic assembly tooling, and releases the robot gripper; S344: The locking mechanism of the automatic assembly tooling locks the workpiece to be welded.

6. The electron beam welding method for automatic assembly according to claim 5, characterized in that, the said sub-steps S342 and S343 are docked through the spherical block on the robot gripper of the automatic assembly robot and the grasping and positioning guide hole on the grasping and positioning tooling for positioning and grasping.

7. The electron beam welding method for automated assembly according to any one of claims 1 to 6, characterized in that, in steps S1 to S2, an AGV transport device is used, and the transfer of the workpiece to be welded is completed by docking the AGV transfer tray with the docking station of the next working station.

8. The electron beam welding method for automated assembly according to any one of claims 1 to 6, characterized in that, in step S3, an AGV transfer device is used, and the transfer of the assembled workpiece is completed by docking the base of the automatic assembly tooling with the docking station of the next working station.

9. The electron beam welding method for automated assembly according to any one of claims 1 to 6, characterized in that, step S4 includes the following sub-steps: S410: Use a laser 3D camera to detect the assembly gap of the workpiece; S420: If the detected docking gap is more than 0.1 mm, an alarm is given for non-conformity, and manual pre-adjustment of the docking gap is carried out. If the detected docking gap < 0.1 mm, the next process is directly carried out; S430: The collaborative arm robot performs laser positioning welding on the qualified area to be welded. S440: The assembled parts are transferred to the electron beam welding station by the logistics system.

10. An electron beam welding production line for automated assembly, characterized in that, it is used to implement the electron beam welding method for automated assembly according to any one of claims 1 to 9.

Images