A non-standard friction stir welding auxiliary equipment

Abstract

This invention relates to the field of machining technology, and more particularly to a non-standard friction stir welding auxiliary equipment. It includes a base, a positioning mechanism, a friction welding boss, and a clamping device. The positioning mechanism is mounted on the base and includes a first positioning mechanism and a second positioning mechanism. By setting positioning mechanisms at the upper left and lower right sides of the auxiliary equipment, the invention provides horizontal constraint on the product from the bottom of the housing, effectively resisting the torsional torque generated during friction stir welding and preventing the product from rotating or shifting during welding. Throughout the welding stroke, the trajectory of the friction stir welding head remains consistent with the joint between the housing and the cover plate, avoiding welding defects such as weld deviation from the weld seam. By incorporating heat dissipation grooves to help reduce the temperature of the auxiliary equipment, combined with the positioning mechanism, the probability of housing deformation during welding is further reduced, and the stability of the welding process is improved, thus enhancing welding quality.

Description

Technical Field

[0001] This invention relates to the field of machining technology, specifically to a non-standard auxiliary equipment for friction stir welding. Background Technology

[0002] Friction stir welding (FSW) is a solid-state joining technology that uses a high-speed rotating friction stir welding head inserted into the joint of workpieces. Friction heat is generated, plasticizing the materials, and a connection is achieved under pressure. This technology offers advantages such as minimal welding deformation, no smoke or dust, and no spatter, and is widely used in welding products in fields such as new energy vehicles and aerospace. Particularly in the production of OBC (On-Board Charger) products for new energy vehicles, FSW is commonly used to connect the housing and cover. As a crucial component of the on-board charger, the welding quality of the OBC housing directly affects the product's sealing and reliability.

[0003] In the prior art, Chinese utility model patent CN214236733U discloses an auxiliary device for friction stir welding with air cooling function for OBC shells. This auxiliary device includes an auxiliary device base plate, a cooling base plate, base blocks, a clamping device, and a cooling system. Several base blocks are installed on the upper part of the cooling base plate, and the base blocks are spliced ​​to form a boss for supporting and limiting the OBC shell. Multiple air cooling main channels are provided inside the cooling base plate. One end of each main air cooling channel penetrates the side wall of the cooling base plate, and the other end branches to connect to multiple air cooling auxiliary channels. An air inlet pipe is connected to the middle of each main air cooling channel, and the inlet end of the air inlet pipe has a connector, which is connected to an air compressor via an air pipe. Some of the air cooling auxiliary channels have vertical channels, the upper ends of which extend into the base blocks to achieve targeted cooling of the OBC shell. This technical solution uses compressed air connected to an air-cooling channel to cool the OBC shell, achieving rapid temperature reduction and eliminating thermal deformation of the OBC shell during friction stir welding, thus ensuring product quality. After welding, the OBC shell temperature drops quickly, shortening the part removal waiting time and increasing production capacity.

[0004] However, this technical solution primarily addresses thermal deformation through cooling, but its positioning mechanism, consisting of bosses formed by splicing base blocks, only serves basic support and limitation, failing to optimize the dynamic stability of the product during welding. While cooling reduces overall heat input, localized thermal stress and mechanical pressure generated during welding still exist, making it difficult to completely eliminate the tendency for product displacement and torsion during welding solely through cooling. The core quality requirement of friction stir welding is that the trajectory of the friction stir welding head must remain consistent with the joint between products. Furthermore, although cooling reduces overall deformation, it lacks specific design for horizontal constraint of the product. During welding, the friction stir welding head generates significant torsional torque as it travels along the weld seam. If the product lacks sufficient horizontal constraint, slight rotation may still occur, causing the weld bead to deviate from the intended weld seam. Summary of the Invention

[0005] The purpose of this invention is to provide a non-standard friction stir welding auxiliary device that can solve the problems mentioned in the background art of inconsistent welding track and weld and easy product deformation.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a non-standard friction stir welding auxiliary device, comprising a base, and further comprising:

[0007] A positioning mechanism is disposed on a base, the positioning mechanism including a first positioning mechanism and a second positioning mechanism; the positioning mechanism includes a base and a positioning column, the base being fixed on the base, and the positioning column being fixedly connected above the base;

[0008] Friction welding boss: It is set on the base, formed by splicing multiple base blocks, and located within the area surrounded by the positioning mechanism;

[0009] Clamping device: disposed on the base and surrounding the friction welding boss.

[0010] Preferably, the first positioning mechanism and the second positioning mechanism are respectively arranged along the length direction and the width direction of the friction welding boss.

[0011] Preferably, the friction welding boss includes a support surface and a heat dissipation groove, the heat dissipation groove being formed by the gap between the base blocks.

[0012] Preferably, the pressing device includes a cylinder, a rotating seat, and a pressure plate. The upper end of the piston rod of the cylinder is rotatably connected to the pressure plate. The upper end of the cylinder is provided with a rotating seat on one side of the piston rod. A connecting plate is rotatably installed on each side of the rotating seat. The two connecting plates are rotatably connected to the two sides of the middle part of the pressure plate, respectively. A pad is installed on the lower part of the front end of the pressure plate.

[0013] Preferably, lifting rings are installed at the four corners of the base.

[0014] Preferably, a pneumatic control valve is provided on the right side of the base, and the pneumatic control valve is electrically connected to the clamping device.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0016] 1. This invention provides horizontal constraints on the product from the bottom of the housing by setting positioning mechanisms at the upper left and lower right corners of the auxiliary equipment body. This near-diagonal layout creates a long constraint arm, effectively resisting the torsional torque generated during friction stir welding and preventing the product from rotating or shifting during welding. Simultaneously, the positioning mechanism extends from below into the positioning part at the bottom of the housing, acting directly on the housing body. The constraint force transmission path is short, allowing for more effective transmission of the positioning constraint to the welding area at the top. Therefore, throughout the entire welding stroke, the trajectory of the friction stir welding head remains consistent with the joint between the housing and the cover plate, avoiding welding defects such as weld deviation from the weld seam.

[0017] 2. This invention incorporates heat dissipation grooves, which serve two purposes: firstly, as exhaust channels to prevent an air cushion effect between the product and auxiliary equipment, ensuring a perfect fit; and secondly, as heat dissipation channels to increase airflow and help reduce the temperature of the auxiliary equipment. Combined with a positioning mechanism, this further reduces the probability of shell deformation during welding and improves the stability of the welding process, maintaining consistency between the welding track and the weld seam, thus enhancing welding quality. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0019] Figure 2 This is a top view of the present invention;

[0020] Figure 3 This is a schematic diagram of the installation position of the shell and cover plate in this invention;

[0021] Figure 4 This is a schematic diagram of the positioning mechanism in this invention;

[0022] Figure 5 This is a schematic diagram of the pressing device in this invention.

[0023] In the diagram: 1. Base; 2. Friction welding boss; 21. Base block; 22. Heat dissipation groove; 3. First positioning mechanism; 31. Base; 32. Positioning column; 4. Second positioning mechanism; 5. Clamping device; 51. Cylinder; 52. Rotating seat; 53. Connecting plate; 54. Pressure plate; 55. Pad plate; 6. Lifting ring; 7. Pneumatic control valve; 8. Housing; 9. Cover plate. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Example 1

[0026] Please see Figures 1-5 A non-standard friction stir welding auxiliary device, including a base 1, and further comprising:

[0027] A positioning mechanism is provided on the base 1. The positioning mechanism includes a first positioning mechanism 3 and a second positioning mechanism 4. The first positioning mechanism 3 and the second positioning mechanism 4 cooperate with each other to perform bidirectional constraint positioning on the housing 8. The positioning mechanism includes a base 31 and a positioning column 32. The base 31 is fixed on the base 1, and the positioning column 32 is fixedly connected above the base 31. The upper part of the positioning column 32 is in the shape of a frustum.

[0028] Friction welding boss 2: It is set on the base 1, formed by splicing multiple base blocks 21 and located within the area surrounded by the positioning mechanism;

[0029] Clamping device 5: It is set on the base 1 and surrounds the friction welding boss 2.

[0030] Overall working principle: The frustum shape at the top of the positioning post 32 fits into the positioning groove at the bottom of the housing 8. When the housing 8 is placed on the auxiliary equipment, the positioning groove at the bottom of the housing 8 fits onto the positioning post 32, and the outer circular surface of the positioning post 32 contacts the inner wall of the positioning groove, thereby restricting the movement of the housing 8 in the horizontal plane, i.e., in the X and Y directions. The conical surface of the positioning post 32 acts as a guide when the housing 8 is placed. The first positioning mechanism 3 and the second positioning mechanism 4 are respectively located at approximately diagonal positions on the base 1, at the upper left corner and the lower right side, respectively. The two positioning points have a large span in both the horizontal and vertical directions, forming a long lever arm, thus providing a sufficiently large resisting torque to effectively prevent the housing 8 from rotating during welding. When the friction stir welding head applies a torsional torque to the housing 8 during welding, the two positioning mechanisms work together to resist the torque. When the clamping device 5 applies a clamping force, the housing 8 tends to move downwards, and the positioning mechanism provides auxiliary support in the vertical direction to prevent the housing 8 from sinking excessively.

[0031] The friction-welded boss 2 is located within the area enclosed by the positioning mechanism, and serves to support the housing 8. The clamping device 5 applies a downward clamping force to the housing 8 and the cover plate 9. The clamping device 5 is arranged around the friction-welded boss 2, forming multi-point clamping to ensure even distribution of the clamping force and prevent excessive localized stress that could cause deformation. The clamping force direction of the clamping device 5 is perpendicular to the constraint direction of the positioning mechanism, forming an orthogonal constraint system.

[0032] The housing 8 is placed on the auxiliary equipment, the friction welding boss 2 provides support, the positioning mechanism provides horizontal and vertical constraint, and the clamping device 5 provides clamping force. During the welding process, the housing 8 and the cover plate 9 are kept still, so that the weld bead and weld seam trajectory are consistent.

[0033] Example 2

[0034] The solution in Example 1 will be further described below with reference to its specific working method.

[0035] The first positioning mechanism 3 and the second positioning mechanism 4 are respectively arranged along the length and width directions of the friction welding boss 2.

[0036] Local working principle: The first positioning mechanism 3 is set along the length direction of the friction welding boss 2, and the second positioning mechanism 4 is set along the width direction of the friction welding boss 2. They precisely constrain the shell 8 in the length and width directions respectively, which can effectively resist the torsional torque in any direction.

[0037] The friction welding boss 2 includes a support surface and a heat dissipation groove 22, which is formed by the gap between the base blocks 21.

[0038] Local working principle: The upper surface of the friction welding boss 2, formed by splicing multiple base blocks 21, constitutes a support surface, which contacts the bottom of the shell 8 and is adapted to the shape of the shell 8, bearing the weight of the shell 8 and the clamping force during the welding process. During the friction stir welding process, a large amount of heat is conducted through the shell 8 to the friction welding boss 2 in contact with it. The heat dissipation groove 22 increases the heat dissipation area of ​​the friction welding boss 2 and forms an air circulation channel, allowing heat to dissipate to the surrounding air more quickly, reducing the accumulation of heat inside the friction welding boss 2, and preventing the friction welding boss 2 from deforming due to thermal expansion, thereby maintaining the stability of the positioning accuracy and further ensuring the consistency of the weld bead and weld seam.

[0039] The pressing device 5 includes a cylinder 51, a rotating seat 52, and a pressure plate 54. The upper end of the piston rod of the cylinder 51 is rotatably connected to the pressure plate 54. The upper end of the cylinder 51 is provided with a rotating seat 52 on one side of the piston rod. A connecting plate 53 is rotatably installed on each side of the rotating seat 52. The two connecting plates 53 are rotatably connected to the two sides of the middle part of the pressure plate 54 respectively. A pad 55 is installed on the lower part of the front end of the pressure plate 54.

[0040] Partial working principle: When the piston rod of cylinder 51 is in the retracted state, the rear end of pressure plate 54 is pulled down and the front end of pressure plate 54 is raised away from the surface of housing 8, allowing for the removal and placement of housing 8; when cylinder 51 is vented, the piston rod extends upward, pushing the rear end of pressure plate 54 upward. With the connection point between connecting plate 53 and rotating seat 52 as the fulcrum, pressure plate 54 is driven by the linkage mechanism to swing the front end of pressure plate 54 downward. The pad 55 at the front end of pressure plate 54 presses against the upper surface of housing 8 and cover plate 9, applying a downward clamping force. As the piston rod continues to extend, the clamping force gradually increases until the set pressure is reached. The cylinder 51 remains in the venting state, the piston rod remains in the extended position, and the pressure plate 54 continuously applies clamping force, pressing the housing 8 and the cover plate 9 onto the friction welding boss 2. The pad 55 makes flexible contact with the housing 8 and the cover plate 9 to avoid damaging the product surface. When the cylinder 51 exhausts air, the piston rod retracts, and the piston rod pulls the rear end of the pressure plate 54 downward, lifting the front end of the pressure plate 54 away from the product surface. The clamping force is released, and the welded product can be taken out.

[0041] The friction welding boss 2 can be adapted to different housings 8 and can be widely used in various friction welding products, especially in OBC products with similar structures, where it has strong adaptability.

[0042] Hanging rings 6 are installed at the four corners of the base 1.

[0043] Local working principle: Lifting ring 6 is used for lifting and moving auxiliary equipment. During lifting, the hook is engaged with lifting ring 6, and the lifting force is transmitted to the base 1 through lifting ring 6. The force is evenly distributed at four points to keep the auxiliary equipment balanced, facilitating safe and stable movement.

[0044] A pneumatic control valve 7 is provided on the right side of the base 1, and the pneumatic control valve 7 is electrically connected to the clamping device 5.

[0045] Local working principle: After receiving instructions from the control system, the compressed air is controlled to flow on and off and in the direction of the compressed air, which is then distributed to each cylinder 51 through the air pipe, driving the pressure plate 54 to achieve pressing or releasing actions. The control valve integrates multi-channel control, enabling independent or synchronous operation of each pressing device 5, ensuring that pressing force is applied after the product is accurately positioned, maintaining stable pressure during welding, and releasing the pressure in a timely manner after welding, thus achieving fully automated control of the entire process.

[0046] Example 3

[0047] The solutions in Embodiments 1 and 2 will be further described below with reference to their specific working methods.

[0048] Preparation phase:

[0049] With the pneumatic control valve 7 in the de-energized state, the pressure plate 54 of the clamping device 5 is raised and in the released position. Clean the support surface of the friction welding boss 2 and the heat dissipation groove 22 to ensure there are no foreign objects.

[0050] Product placement and positioning stage:

[0051] The housing 8 is transported above the auxiliary equipment and slowly lowered so that the positioning hole at the bottom of the housing 8 is aligned with the positioning post 32 of the first positioning mechanism 3 and the second positioning mechanism 4. The frustum shape at the top of the positioning post 32 guides the housing 8 to automatically center, and the positioning hole smoothly fits into the positioning post 32. The two positioning mechanisms form an orthogonal constraint, which together restricts the horizontal movement and rotation of the housing 8. The bottom of the housing 8 contacts the support surface of the friction welding boss 2. The support surface bears the weight of the housing 8. The cover plate 9 is placed at the opening at the top of the housing 8 so that the edge of the cover plate 9 is aligned with the edge of the opening of the housing 8.

[0052] Compacting stage:

[0053] The control system sends a clamping signal, energizes the pneumatic control valve 7, and compressed air enters the cylinders 51 of each clamping device 5 through the control valve and air pipe. The piston rod of the cylinder 51 extends, pushing the rear end of the pressure plate 54 upward. The pressure plate 54 swings around the connection point between the connecting plate 53 and the rotating seat 52, causing the front end of the pressure plate 54 to press down. The pad 55 at the front end of the pressure plate 54 contacts the housing 8 and the cover plate 9, applying a downward clamping force. During the clamping process, the air between the bottom of the housing 8 and the support surface is discharged through the heat dissipation groove 22 to avoid the air cushion effect. The clamping force makes the housing 8 and the support surface fit tightly together, increasing the friction and assisting in horizontal constraint. After the clamping force reaches the set value, the control valve remains in the state, and the clamping device 5 continues to apply pressure.

[0054] Welding stage:

[0055] The friction stir welding head is started and welding is performed along the peripheral weld between the housing 8 and the cover plate 9. During the welding process, the friction stir welding head applies varying forces and torques to the housing 8. The two positioning mechanisms work together to resist the torque, and the clamping device 5 continuously applies clamping force to resist the axial force of the friction stir welding head and prevent the housing 8 from lifting. The support surface of the friction welding boss 2 maintains stable support, and the heat dissipation groove 22 assists in heat dissipation and reduces thermal deformation. The two orthogonal positioning mechanisms, together with the clamping device 5 and the friction welding boss 2, work together to ensure that the travel trajectory of the friction stir welding head is always consistent with the weld.

[0056] Welding completion stage:

[0057] Welding is complete. The friction stir welding head stops rotating and lifts up. The control system sends a release signal, the pneumatic control valve 7 switches states, the piston rod retracts, the rear end of the pressure plate 54 is pulled down, and the front end is lifted away from the product surface. The clamping force is released, and the product can cool naturally on the auxiliary equipment. The welded housing 8 and cover plate 9 assembly is then lifted and removed from the auxiliary equipment.

[0058] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0059] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A non-standard friction stir welding auxiliary device, comprising a base (1), characterized in that, Also includes: A positioning mechanism is provided on the base (1). The positioning mechanism includes a first positioning mechanism (3) and a second positioning mechanism (4). The positioning mechanism includes a base (31) and a positioning column (32). The base (31) is fixed on the base (1), and the positioning column (32) is fixedly connected above the base (31). Friction welding boss (2): It is set on the base (1), formed by splicing multiple base blocks (21), and located in the area surrounded by the positioning mechanism; Clamping device (5): set on the base (1) and surrounding the friction welding boss (2).

2. The non-standard friction stir welding auxiliary equipment according to claim 1, characterized in that: The first positioning mechanism (3) and the second positioning mechanism (4) are respectively arranged along the length direction and the width direction of the friction welding boss (2).

3. The non-standard friction stir welding auxiliary equipment according to claim 1, characterized in that: The friction welding boss (2) includes a support surface and a heat dissipation groove (22), which is formed by the gap between the base blocks (21).

4. The non-standard friction stir welding auxiliary equipment according to claim 1, characterized in that: The pressing device (5) includes a cylinder (51), a rotating seat (52) and a pressure plate (54). The upper end of the piston rod of the cylinder (51) is rotatably connected to the pressure plate (54). The upper end of the cylinder (51) is provided with a rotating seat (52) on one side of the piston rod. A connecting plate (53) is rotatably installed on each side of the rotating seat (52). The two connecting plates (53) are rotatably connected to the two sides of the middle part of the pressure plate (54) respectively. A pad (55) is installed at the lower part of the front end of the pressure plate (54).

5. A non-standard friction stir welding auxiliary equipment according to claim 1, characterized in that: Hanging rings (6) are installed at the four corners of the base (1).

6. The non-standard friction stir welding auxiliary equipment according to claim 1, characterized in that: A pneumatic control valve (7) is provided on the right side of the base (1), and the pneumatic control valve (7) is electrically connected to the clamping device (5).

Images