Friction stir welding transverse pretightening force device and control method thereof

Abstract

The invention discloses a friction stir welding transverse pretightening force device and a control method thereof. The friction stir welding transverse pretightening force device comprises a positioning mechanism and a transverse pretightening force output structure, wherein the positioning mechanism is used for positioning a welded part; the transverse pretightening force output structure is used for applying transverse pretightening force to the welded part; the positioning mechanism comprises a friction stir welding platform used for placing the welded part, longitudinal positioning blocks arranged on the left side and the right side of the welded part and a transverse positioning block arranged on the lower side of the welded part. The transverse pre-tightening force output structure comprises a guide block arranged on the upper side of the welded part and a linear motor push rod. During welding, the output end of the push rod of the linear motor extends to push the guide block to make contact with the welded part, and transverse pre-tightening force is applied to the welded part. According to the friction stir welding transverse pretightening force device, transverse pretightening force can be provided for a welded part in the welding process, and the welding seam quality of friction stir welding can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of friction stir welding, and in particular to a friction stir welding transverse preload device and a control method thereof. Background Art

[0002] Friction stir welding is more and more widely used in aluminum alloys and magnesium alloys. The existing friction stir welding technology can achieve the welding thickness range of aluminum alloys from 1mm to 75mm. During the welding process, the high-speed rotating stirring needle extends into the butt joint gap of the workpiece, and the rotating stirring head and the shoulder of the stirring head rub against the workpiece to generate heat, so that the material in front of the stirring head undergoes strong plastic deformation. With the movement of the high-speed rotating stirring head, the highly plastically deformed material gradually deposits behind the stirring head, thereby forming a friction stir welding weld. The requirements of friction stir welding on equipment are not high. The most basic requirements are the rotation of the welding head and the relative movement of the workpiece. However, the rigidity of the equipment and fixture of friction stir welding plays a vital role in the quality of the weld. In order to prevent the movement of the workpiece to be welded and ensure the quality of the weld, welding fixtures and tooling devices are used to fix the workpiece to be welded. The friction stir welding welding platform of the present invention is integrally machined and formed. After the machining and forming, the surface is quenched. Improving the surface hardness of the device can reduce the difficulty of welding and improve the quality of the weld.

[0003] The transverse preload device for friction stir welding is an important component of the friction stir welding process. Generally speaking, the transverse preload device for friction stir welding is mainly composed of a welding plane that can provide high flatness, a high-precision positioning structure, and a clamping structure. The flatness of the friction stir welding tooling itself is relatively high. The transverse preload device for friction stir welding determines the success or failure of friction stir welding. A tooling device with a reasonable structural design can obtain a more reliable friction stir welding weld.

[0004] Most of the existing friction stir welding tools can provide a high-precision welding plane, a high-precision positioning structure, and a clamping structure, but the existing friction stir welding tools do not provide a preload force and cannot achieve welds with high precision requirements. Summary of the invention

[0005] In order to solve at least one technical problem in the above-mentioned background technology, the present invention proposes a friction stir welding transverse preload device and a control method thereof.

[0006] In order to achieve the above-mentioned object, according to one aspect of the present invention, a lateral preload device for friction stir welding is provided, the device comprising: a positioning mechanism for positioning a welded part and a lateral preload output structure for applying a lateral preload to the welded part;

[0007] The positioning mechanism includes: a friction stir welding welding platform for placing the welded part, longitudinal positioning blocks arranged on the left and right sides of the welded part, and a transverse positioning block arranged on the lower side of the welded part; the transverse preload force output structure includes: a guide block arranged on the upper side of the welded part and a linear motor push rod; when welding, the output end of the linear motor push rod extends to push the guide block to contact the welded part, thereby applying a transverse preload force to the welded part.

[0008] Optionally, the friction stir welding transverse preload device further includes: a pressure sensor and a controller;

[0009] The pressure sensor is used to detect the lateral preload force actually output by the lateral preload force output structure; the controller is used to control the extension length of the output end according to the lateral preload force actually output by the lateral preload force output structure, so that the lateral preload force actually output by the lateral preload force output structure is equal to the preset required lateral preload force corresponding to the welded part.

[0010] Optionally, the lateral preload output structure also includes: a transfer connecting rod and a transfer block; the transfer connecting rod is fixedly connected to the guide block and the transfer block respectively; when welding, the output end of the linear motor push rod extends to push the transfer block, thereby driving the guide block to move and contact the welded part, thereby applying a lateral preload to the welded part.

[0011] Optionally, the pressure sensor is arranged at the connection between the adapter connecting rod and the guide block, or the pressure sensor is arranged at the connection between the adapter connecting rod and the adapter block.

[0012] Optionally, the friction stir welding transverse preload device further comprises: a guide structure for guiding the transverse preload output structure;

[0013] The guide structure comprises: a guide rod adapter block, a guide rod and a guide rod positioning block;

[0014] The guide rod positioning block is fixed on the friction stir welding platform; the guide rod positioning block is connected to the guide rod, and the position of the guide rod is fixed by the guide rod positioning block; the guide rod adapter block passes through the guide rod, the guide rod adapter block can move along the guide rod, and the guide rod adapter block is fixedly connected to the guide block.

[0015] Optionally, the guide rod adapter block is fixedly connected to the adapter block; the axis of the guide block is parallel to the axis of the adapter block; the axis of the guide rod is perpendicular to the axis of the guide block and the axis of the adapter block; the axis of the guide rod is parallel to the surface of the stir friction welding platform.

[0016] Optionally, there are two guide structures, which are respectively arranged on the left and right sides of the transverse preload force output structure; and the axes of the guide rods of the two guide structures are parallel.

[0017] Optionally, the friction stir welding lateral preload device further includes: a displacement sensor; the displacement sensor is used to detect the lateral displacement size of the welded part after the lateral preload force is applied to the welded part; the controller is also used to adjust the size of the lateral preload force output by the lateral preload force output structure by controlling the extension length of the output end according to the lateral displacement size and the preset lateral displacement corresponding to the welded part.

[0018] Optionally, the displacement sensor is arranged at the connection between the adapter connecting rod and the guide block, or the displacement sensor is arranged at the connection between the adapter connecting rod and the adapter block.

[0019] Optionally, the friction stir welding transverse preload device further includes: a combined friction stir welding stirring head; the combined friction stir welding stirring head includes: a stirring head, a retaining frame and a pressure roller.

[0020] Optionally, the friction stir welding lateral preload device further includes: a laser sensor; the laser sensor is used to detect the actual shoulder pressure amount of the stirring head; the controller is also used to control the actual shoulder pressure amount of the stirring head to reach a preset target pressure amount.

[0021] Optionally, the laser sensor is arranged on the guide block.

[0022] In order to achieve the above object, according to another aspect of the present invention, a control method for a friction stir welding transverse preload device is provided, the method being applied to the above-mentioned friction stir welding transverse preload device, the method comprising:

[0023] Before welding begins, the controller controls the linear motor push rod to reset to zero, the workpiece to be welded is placed on the friction stir welding platform, the long side of the workpiece to be welded is effectively contacted with the transverse positioning block, and the short side of the workpiece to be welded is effectively contacted with the longitudinal positioning block;

[0024] When welding begins, the controller controls the output end of the linear motor push rod to extend so as to apply a transverse pre-tightening force to the welded part.

[0025] Optionally, the control method of the friction stir welding transverse preload device further includes:

[0026] Detecting the lateral preload force actually output by the lateral preload force output structure by means of the pressure sensor;

[0027] The controller controls the extension length of the output end according to the lateral preload force actually output by the lateral preload force output structure, so that the lateral preload force actually output by the lateral preload force output structure is equal to the preset required lateral preload force corresponding to the welded part.

[0028] Optionally, the control method of the friction stir welding transverse preload device further includes:

[0029] Detecting the lateral displacement of the welded part after the lateral pre-tightening force is applied thereto by the displacement sensor;

[0030] The controller adjusts the magnitude of the lateral preload output by the lateral preload output structure by controlling the extension length of the output end according to the magnitude of the lateral displacement and the preset lateral displacement corresponding to the welded part.

[0031] Optionally, the control method of the friction stir welding transverse preload device further includes:

[0032] Detecting the actual shoulder pressing amount of the stirring head by the laser sensor;

[0033] The controller controls the actual shoulder pressing amount of the stirring head to reach a preset target pressing amount.

[0034] The beneficial effects of the present invention are:

[0035] The friction stir welding transverse preload device of the present invention comprises a transverse preload output structure for applying transverse preload to the welded parts, which can provide transverse preload to the welded parts during welding and help improve the weld quality of friction stir welding. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0037] Figure 1 is a first schematic diagram of a friction stir welding transverse preload device according to an embodiment of the present invention;

[0038] Figure 2 is a second schematic diagram of a friction stir welding transverse preload device according to an embodiment of the present invention;

[0039] Figure 3 3 is a schematic diagram of a friction stir welding transverse preload device according to an embodiment of the present invention.

[0040] In the attached drawings: 1. Friction stir welding welding platform; 2. Longitudinal positioning block; 3. Pin; 4. Positioning block fixing screw; 5. Transverse positioning block; 6. Part to be welded; 7. Combined friction stir welding stirring head; 8. Guide block; 9. Adapter connecting rod; 10. Pressure sensor; 11. Adapter block; 12. Linear motor push rod; 13. Linear motor tail positioning block; 14. Fixing screw; 15. Displacement sensor; 16. Guide rod adapter block; 17. Guide rod; 18. Guide rod positioning block; 21. Laser sensor; 22. Judgment module; 23. Controller; 25. Stirring head; 26. Retaining frame; 27. Pressure roller. DETAILED DESCRIPTION

[0041] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0042] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0043] It should be noted that the terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or apparatus.

[0044] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0045] The present invention relates to a friction stir welding transverse preload device and a control method thereof, which are used to solve the problem that the current friction stir welding tooling cannot provide a variable transverse preload. The present invention can measure the transverse preload, transverse displacement and vertical pressing amount required by the welded parts during the initial welding, provide a variable preload for the welded parent material during the subsequent welding process, and monitor the size of the transverse preload at all times during the welding process, dynamically adjust the transverse preload, and ultimately ensure the quality of the friction stir welding weld.

[0046] In one embodiment of the present invention, the friction stir welding transverse preload device of the present invention comprises: a positioning mechanism for positioning the welded parts and a transverse preload output structure for applying the transverse preload to the welded parts.

[0047] like Figure 1 As shown, in one embodiment of the present invention, the positioning mechanism of the present invention comprises: a friction stir welding welding platform 1 for placing the welded part 6, longitudinal positioning blocks 2 arranged on the left and right sides of the welded part 6, and a transverse positioning block 5 arranged on the lower side of the welded part 6. In one embodiment of the present invention, the longitudinal positioning block 2 and the transverse positioning block 5 are both arranged on the friction stir welding welding platform 1.

[0048] like Figure 1 As shown, in one embodiment of the present invention, the positioning mechanism of the present invention specifically includes: a friction stir welding platform 1, 2 longitudinal positioning blocks 2 and 4 pins 3, 4 positioning block fixing screws 4, 1 transverse positioning block 5 and 3 pins 3, and 2 positioning block fixing screws 4. Specifically, the friction stir welding platform 1 is processed with threaded holes and pin holes, and the threaded holes and pin holes are used for the installation of the longitudinal positioning block 2 and the transverse positioning block 5. The length of the longitudinal positioning block 2 is equal to that of the welded part 6, and the longitudinal positioning block 2 changes with the change of the length of the welded part 6. The transverse positioning block 5 is processed with a pin hole to ensure that the longitudinal positioning block 2 is parallel to the weld, and at the same time ensure that the longitudinal positioning block 2 and the transverse positioning block 5 have a high verticality.

[0049] like Figure 1 As shown, in one embodiment of the present invention, the lateral preload force output structure of the present invention comprises: a guide block 8 disposed on the upper side of the welded part and a linear motor push rod 12. When welding, the output end of the linear motor push rod 12 extends to push the guide block 8 to contact the welded part 6, thereby applying a lateral preload force to the welded part 6.

[0050] like Figure 2 As shown, in one embodiment of the present invention, the friction stir welding transverse preload device of the present invention further includes: a pressure sensor 10 and a controller 23.

[0051] In one embodiment of the present invention, the pressure sensor 10 is used to detect the lateral preload force actually output by the lateral preload force output structure.

[0052] In one embodiment of the present invention, the controller 23 is used to control the extension length of the output end according to the lateral preload force actually output by the lateral preload force output structure, so that the lateral preload force actually output by the lateral preload force output structure is equal to the preset required lateral preload force corresponding to the welded part.

[0053] like Figure 2 As shown, in one embodiment of the present invention, the stir friction welding lateral preload device of the present invention further includes: a judgment module 22, the judgment module 22 is used to determine whether the lateral preload actually output by the lateral preload output structure is equal to the preset required lateral preload corresponding to the welded part.

[0054] like Figure 1 As shown, in one embodiment of the present invention, the lateral preload force output structure further includes: a transfer connecting rod 9 and a transfer block 11; the transfer connecting rod 9 is respectively fixedly connected to the guide block 8 and the transfer block 11. During welding, the output end of the linear motor push rod 12 extends to push the transfer block 11, thereby driving the guide block 8 to move and contact the welded part 6, and applying a lateral preload force to the welded part 6.

[0055] like Figure 1 As shown, in one embodiment of the present invention, the lateral preload force output structure specifically includes: a guide block 8, an adapter connecting rod 9, an adapter block 11, two linear motor push rods 12, two linear motor tail positioning blocks 13 and their fixing screws 14. The detailed installation steps are as follows: fix the pressure sensor 10 and the adapter block 11 with hexagon socket cylindrical head screws, and then fix the guide block 8 and the adapter connecting rod 9 with hexagon socket cylindrical head screws. After fixation, the guide block 8 and the adapter block 11 can slide along the axial direction of the guide rod 17 in the plane of the stir friction welding platform 1; then, fix the pressure sensor 10 and the adapter connecting rod 9 with hexagon socket cylindrical head screws; install the fixed shaft at the end of the linear motor push rod 12 into the corresponding hole of the adapter block 11, and connect the linear motor push rod 12 and the adapter block 11 with hexagon socket cylindrical head screws. Finally, use the hexagon socket cylindrical head screw to fix the linear motor push rod 12 to the surface of the stir friction welding platform 1 through the linear motor tail positioning block 13 to prevent the linear motor push rod 12 from moving.

[0056] In one embodiment of the present invention, the pressure sensor 10 is disposed at the connection between the adapter connecting rod 9 and the guide block 8. In another embodiment of the present invention, the pressure sensor 10 is disposed at the connection between the adapter connecting rod 9 and the adapter block 11.

[0057] In one embodiment of the present invention, the friction stir welding transverse preload device of the present invention further includes: a guide structure for guiding the transverse preload output structure.

[0058] like Figure 1 As shown, in one embodiment of the present invention, the guide structure includes: a guide rod adapter block 16 , a guide rod 17 and a guide rod positioning block 18 .

[0059] like Figure 1 As shown, in one embodiment of the present invention, the guide rod positioning block 18 is fixed on the stir friction welding platform 1; the guide rod positioning block 18 is connected to the guide rod 17, and the position of the guide rod 17 is fixed by the guide rod positioning block 18; the guide rod adapter block 16 passes through the guide rod 17, the guide rod adapter block 16 can move along the guide rod 17, and the guide rod adapter block 16 is fixedly connected to the guide block 8.

[0060] like Figure 1 As shown, in one embodiment of the present invention, the guide rod adapter block 16 is fixedly connected to the adapter block 11, the axis of the guide block 8 is parallel to the axis of the adapter block 11, and the axis of the guide rod 17 is perpendicular to the axis of the guide block 8 and the axis of the adapter block 11. The axis of the guide rod 17 is parallel to the surface of the friction stir welding platform 1.

[0061] like Figure 1 As shown, in one embodiment of the present invention, there are two guide structures, which are respectively arranged on the left and right sides of the lateral preload force output structure; the axes of the guide rods 17 of the two guide structures are parallel.

[0062] like Figure 1 As shown, in one embodiment of the present invention, the friction stir welding transverse preload device of the present invention has two sets of guide structures, which are composed of a guide rod adapter block 16, a guide rod 17, and a guide rod positioning block 18. The detailed installation instructions are as follows: install the guide rod adapter block 16 on the guide rod 17, and then install the guide rod positioning block 18 on the friction stir welding platform 1. After installation, ensure that the axis of the guide rod 17 is parallel to the surface of the friction stir welding platform 1. After the above installation is completed, the guide rod adapter block 16 is fixed to the corresponding positions of the guide block 8 and the adapter block 11 by a hexagon socket head screw, wherein the guide rod adapter block 16 is coaxial with the guide rod 17.

[0063] like Figure 2 As shown, in one embodiment of the present invention, the friction stir welding transverse preload device of the present invention further includes: a displacement sensor 15.

[0064] In one embodiment of the present invention, the displacement sensor 15 is used to detect the lateral displacement of the welded part 6 after the lateral pre-tightening force is applied thereto.

[0065] In one embodiment of the present invention, the controller 23 is also used to adjust the size of the lateral preload output by the lateral preload output structure by controlling the extension length of the output end according to the size of the lateral displacement and the preset lateral displacement corresponding to the welded part.

[0066] In one embodiment of the present invention, the judgment module 22 is further used to determine whether the magnitude of the lateral displacement of the welded component 6 after the lateral pre-tightening force is applied thereto is equal to a preset lateral displacement corresponding to the welded component.

[0067] In one embodiment of the present invention, the displacement sensor 15 is disposed at the connection between the adapter connecting rod 9 and the guide block 8. In another embodiment of the present invention, the displacement sensor 15 is disposed at the connection between the adapter connecting rod 9 and the adapter block 11.

[0068] In one embodiment of the present invention, the friction stir welding transverse preload device of the present invention further includes: a combined friction stir welding stirring head 7 .

[0069] like Figure 1 As shown, in one embodiment of the present invention, the combined friction stir welding stirring head includes: a stirring head 25, a retaining frame 26 and a pressure roller 27.

[0070] In one embodiment of the present invention, the combined stir friction welding stirring head 7 can provide a vertical clamping force. After the welding starts, the retaining frame 26 moves with the stirring head 25 toward the welded workpiece 6. Finally, the stirring needle extends into the welded workpiece 6 and the pressure roller 27 contacts the welded workpiece 6. The pressure roller 27 and the welded workpiece 6 have a certain vertical pre-tightening force.

[0071] like Figure 2 As shown, in one embodiment of the present invention, the friction stir welding transverse preload device of the present invention further includes: a laser sensor 21.

[0072] In one embodiment of the present invention, the laser sensor 21 is used to detect the actual shoulder pressing amount of the stirring head.

[0073] In one embodiment of the present invention, the controller 23 is further used to control the actual shoulder pressing amount of the stirring head to reach a preset target pressing amount.

[0074] like Figure 1 As shown, in one embodiment of the present invention, the laser sensor 21 is disposed on the guide block 8 .

[0075] like Figure 3As shown, in one embodiment of the present invention, the material of the friction stir welding platform 1 in the friction stir welding transverse preload device of the present invention is formed by integral mechanical processing of 45# steel to ensure that the flatness of the contact surface between the friction stir welding platform 1 and the welded part 6 is 0.1. The length L4 of the transverse positioning block 5 is equal to the length of the welded part 6, wherein the length of L3 is controlled between 30 and 40 mm, the length L1 of the friction stir welding platform 1 is L4+2*L3, and the length L2 of the friction stir welding platform 1 is determined according to the length of the assembly parts, ensuring that all assembly parts are within the platform. The behavioral tolerance after assembly is as shown in Figure 3 As shown. Among them, the horizontal positioning block 5 is ensured to have a straightness of 0.1 by three pins 3, and is fixed to the surface of the stir friction welding platform 1 by two positioning block fixing screws 4; the two longitudinal positioning blocks 2 are ensured to have a verticality of 0.1 between the contact surface of the positioning block and the welded part 6 and the reference A by four positioning block fixing screws 4; after assembly, the parallelism of the contact surface of the guide block 8 and the welded part 6 and the reference A is ensured to be 0.1, and the high-quality assembly accuracy can ensure the quality of the stir friction welding weld.

[0076] It can be seen from the above embodiments that the friction stir welding transverse preload device of the present invention can not only provide a high-precision welding plane, a high-precision positioning structure, and a transverse clamping structure, but also provide a variable transverse preload for the welded parent material. At the same time, the present invention can be used to test the size of the transverse preload required for friction stir welding of different materials of different thicknesses, and monitor the size of the transverse preload at all times during the welding process. When the transverse preload becomes smaller, the pressure can be increased to increase the preload. When the preload increases a lot during the welding process, the preload can be reduced by reducing the pressure.

[0077] Based on the same inventive concept, an embodiment of the present invention further provides a control method for a stir friction welding transverse preload device, and the control method is applied to the stir friction welding transverse preload device of the above embodiment, as described in the following embodiment. Since the principle of solving the problem by the control method for the stir friction welding transverse preload device is similar to that of the stir friction welding transverse preload device, the embodiment of the control method for the stir friction welding transverse preload device can refer to the embodiment of the stir friction welding transverse preload device, and the repeated parts will not be repeated.

[0078] In one embodiment of the present invention, the control method of the friction stir welding transverse preload device of the present invention comprises:

[0079] Before welding begins, the controller controls the linear motor push rod to reset to zero, the workpiece to be welded is placed on the friction stir welding platform, the long side of the workpiece to be welded is effectively contacted with the transverse positioning block, and the short side of the workpiece to be welded is effectively contacted with the longitudinal positioning block;

[0080] When welding begins, the controller controls the output end of the linear motor push rod to extend so as to apply a transverse pre-tightening force to the welded part.

[0081] In one embodiment of the present invention, the controller 23 is used to reset the linear motor push rod 12 to zero before welding begins, and the welded part 6 is placed on the surface of the stir friction welding platform 1, so that the long side of the welded part 6 is in effective contact with the transverse positioning block 5, and the short side of the welded part 6 is in effective contact with the longitudinal positioning block 2. When welding begins, the controller 23 controls the linear motor push rod 12 to extend to indirectly apply a preset transverse preload to the welded part 6 to achieve the preset preload. In the present invention, the displacement sensor 15 is also controlled to reach a preset position, while ensuring that the stirring head reaches a preset amount of pressure.

[0082] In one embodiment of the present invention, the control method of the friction stir welding transverse preload device of the present invention further includes:

[0083] Detecting the lateral preload force actually output by the lateral preload force output structure by means of the pressure sensor;

[0084] The controller controls the extension length of the output end according to the lateral preload force actually output by the lateral preload force output structure, so that the lateral preload force actually output by the lateral preload force output structure is equal to the preset required lateral preload force corresponding to the welded part.

[0085] In one embodiment of the present invention, during the welding process, the present invention detects the lateral preload by means of a pressure sensor 10, and adjusts the magnitude of the lateral preload according to a preset required lateral preload corresponding to the welded part; when the measured actual output lateral preload F is greater than the preset required lateral preload F0, the preload F is reduced by shortening the stroke of the linear motor push rod 12, so that the measured actual output preload F is equal to F0; when the measured actual output lateral preload F during the welding process is less than F0, the preload F is increased by increasing the stroke of the linear motor push rod 12, so that the measured preload is equal to F0.

[0086] In one embodiment of the present invention, the control method of the friction stir welding transverse preload device of the present invention further includes:

[0087] Detecting the lateral displacement of the welded part after the lateral pre-tightening force is applied thereto by the displacement sensor;

[0088] The controller adjusts the magnitude of the lateral preload output by the lateral preload output structure by controlling the extension length of the output end according to the magnitude of the lateral displacement and the preset lateral displacement corresponding to the welded part.

[0089] In one embodiment of the present invention, during the welding process, the present invention further detects the magnitude of the lateral displacement of the welded part 6 after the lateral pre-tightening force is applied thereto through the displacement sensor 15, and adjusts the magnitude of the lateral pre-tightening force according to the preset lateral displacement corresponding to the welded part. Specifically, if the magnitude of the lateral displacement detected by the displacement sensor 15 exceeds the preset lateral displacement corresponding to the welded part, the output lateral pre-tightening force needs to be reduced so that the magnitude of the detected lateral displacement is equal to the preset lateral displacement; if the magnitude of the lateral displacement detected by the displacement sensor 15 is less than the preset lateral displacement corresponding to the welded part, the output lateral pre-tightening force needs to be increased so that the magnitude of the detected lateral displacement is equal to the preset lateral displacement.

[0090] In one embodiment of the present invention, the control method of the friction stir welding transverse preload device of the present invention further includes:

[0091] Detecting the actual shoulder pressing amount of the stirring head by the laser sensor;

[0092] The controller controls the actual shoulder pressing amount of the stirring head to reach a preset target pressing amount.

[0093] In one embodiment of the present invention, during the welding process, the present invention detects the pressing amount of the shoulder of the stirring head 25 by the laser sensor 21, and dynamically adjusts the pressing amount of the shoulder of the stirring head 25 according to the target pressing amount set in advance.

[0094] It can be seen that the present invention provides a stir friction welding transverse preload device and a control method thereof. The device of the present invention can not only provide a high-precision welding plane and a high-precision positioning structure, but also provide variable transverse and vertical preload for the welded parent material. At the same time, the present invention can be used to test the size of the transverse preload required for stir friction welding of different materials of different thicknesses, and monitor the size of the transverse preload at all times during the welding process. When the transverse preload becomes smaller, the pressure can be increased to increase the preload. When the preload increases a lot during the welding process, the preload can be reduced by reducing the pressure.

[0095] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A friction stir welding transverse preload device, characterized in that: include: A positioning mechanism for positioning a welded part and a transverse preload force output structure for applying a transverse preload force to the welded part; The positioning mechanism includes: a friction stir welding welding platform for placing the welded part, longitudinal positioning blocks arranged on the left and right sides of the welded part, and a transverse positioning block arranged on the lower side of the welded part; the transverse preload force output structure includes: a guide block arranged on the upper side of the welded part and a linear motor push rod; when welding, the output end of the linear motor push rod extends to push the guide block to contact the welded part, thereby applying a transverse preload force to the welded part.

2. The friction stir welding transverse preload device according to claim 1, characterized in that: Also includes: Pressure sensors and controllers; The pressure sensor is used to detect the lateral preload force actually output by the lateral preload force output structure; The controller is used to control the extension length of the output end according to the lateral preload force actually output by the lateral preload force output structure, so that the lateral preload force actually output by the lateral preload force output structure is equal to the preset required lateral preload force corresponding to the welded part.

3. The friction stir welding transverse preload device according to claim 2, characterized in that: The lateral preload output structure also includes: a transfer connecting rod and a transfer block; the transfer connecting rod is fixedly connected to the guide block and the transfer block respectively; when welding, the output end of the linear motor push rod extends to push the transfer block, thereby driving the guide block to move and contact the welded part, applying a lateral preload to the welded part.

4. The friction stir welding transverse preload device according to claim 3, characterized in that: The pressure sensor is arranged at the connection between the adapter connecting rod and the guide block, or the pressure sensor is arranged at the connection between the adapter connecting rod and the adapter block.

5. The friction stir welding transverse preload device according to claim 3, characterized in that: Also includes: A guide structure for guiding the lateral preload force output structure; The guide structure comprises: a guide rod adapter block, a guide rod and a guide rod positioning block; The guide rod positioning block is fixed on the friction stir welding platform; the guide rod positioning block is connected to the guide rod, and the position of the guide rod is fixed by the guide rod positioning block; the guide rod adapter block passes through the guide rod, the guide rod adapter block can move along the guide rod, and the guide rod adapter block is fixedly connected to the guide block.

6. The friction stir welding transverse preload device according to claim 5, characterized in that: The guide rod adapter block is fixedly connected to the adapter block; the axis of the guide block is parallel to the axis of the adapter block; the axis of the guide rod is perpendicular to the axis of the guide block and the axis of the adapter block; the axis of the guide rod is parallel to the surface of the stir friction welding platform.

7. The friction stir welding transverse preload device according to claim 6, characterized in that: There are two guide structures, which are respectively arranged on the left and right sides of the transverse preload force output structure; the axes of the guide rods of the two guide structures are parallel.

8. The friction stir welding transverse preload device according to claim 2, characterized in that: Also includes: A displacement sensor; the displacement sensor is used to detect the size of the lateral displacement of the welded part after the lateral preload force is applied to the welded part; the controller is also used to adjust the size of the lateral preload force output by the lateral preload force output structure by controlling the extension length of the output end according to the lateral displacement size and the preset lateral displacement corresponding to the welded part.

9. The friction stir welding transverse preload device according to claim 8, characterized in that: The displacement sensor is arranged at the connection between the adapter connecting rod and the guide block, or the displacement sensor is arranged at the connection between the adapter connecting rod and the adapter block.

10. The friction stir welding transverse preload device according to claim 8, characterized in that: Also includes: Combined friction stir welding stirring head; The combined friction stir welding stirring head comprises a stirring head, a retaining frame and a pressure roller.

11. The friction stir welding transverse preload device according to claim 10, characterized in that: Also includes: Laser sensor; the laser sensor is used to detect the actual shoulder pressure of the stirring head; the controller is also used to control the actual shoulder pressure of the stirring head to reach a preset target pressure.

12. The friction stir welding transverse preload device according to claim 11, characterized in that: The laser sensor is arranged on the guide block.

13. A control method for a friction stir welding transverse preload device, characterized in that: Applied to the friction stir welding transverse preload device according to claim 11, the method comprises: Before welding begins, the controller controls the linear motor push rod to reset to zero, the workpiece to be welded is placed on the friction stir welding platform, the long side of the workpiece to be welded is effectively contacted with the transverse positioning block, and the short side of the workpiece to be welded is effectively contacted with the longitudinal positioning block; When welding begins, the controller controls the output end of the linear motor push rod to extend so as to apply a transverse pre-tightening force to the welded part.

14. The control method of the friction stir welding transverse preload device according to claim 13, characterized in that: Also includes: Detecting the lateral preload force actually output by the lateral preload force output structure by means of the pressure sensor; The controller controls the extension length of the output end according to the lateral preload force actually output by the lateral preload force output structure, so that the lateral preload force actually output by the lateral preload force output structure is equal to the preset required lateral preload force corresponding to the welded part.

15. The control method of the friction stir welding transverse preload device according to claim 13, characterized in that: Also includes: Detecting the lateral displacement of the welded part after the lateral pre-tightening force is applied thereto by the displacement sensor; The controller adjusts the magnitude of the lateral preload output by the lateral preload output structure by controlling the extension length of the output end according to the magnitude of the lateral displacement and the preset lateral displacement corresponding to the welded part.

16. The control method of the friction stir welding transverse preload device according to claim 13, characterized in that: Also includes: Detecting the actual shoulder pressing amount of the stirring head by the laser sensor; The controller controls the actual shoulder pressing amount of the stirring head to reach a preset target pressing amount.

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