A friction stir welding device based on battery case manufacturing

Abstract

The present invention relates to a friction stir welding device based on battery housing manufacturing, which includes a welding table, a positioning mechanism, a welding mechanism and a cooling mechanism. The welding table has a material placing plane for placing plate members. The positioning mechanism fixes the plate members. The welding mechanism includes a rotating part and a stirring part. The rotating part is controlled to move and drive the stirring part to perform welding. The cooling mechanism includes a housing, a liquid source and a blower. A containing space is provided in the housing, which is connected to a liquid inlet, an air inlet and an exhaust port. An opening is covered at the weld joint and fits with the surface of the plate member. A plurality of partition members are provided in the containing space to form a first heat dissipation flow channel to guide the orderly flow of the coolant and the air flow. This friction stir welding device supplies coolant through the liquid source and provides air flow through the blower to achieve local cooling gradient control in the weld area and its surroundings, avoiding problems such as stress concentration, cracks and reduced strength caused by excessive temperature gradient, while improving the hardness recovery effect of the joint and optimizing the welding quality.

Description

Technical Field

[0001] The present invention relates to a friction stir welding device, and in particular to a friction stir welding device based on battery case manufacturing. Background Art

[0002] Friction stir welding is a solid-phase welding technology, which is widely used in fields such as aerospace, automotive manufacturing, and shipbuilding industries that require high-strength and low-deformation welding. Compared with traditional welding methods, friction stir welding realizes welding through the friction and plastic deformation of a rotating tool, avoiding the porosity and crack defects in fusion welding. However, during the welding process, the material properties in the weld area and its surrounding areas will change due to high temperature, and the grain coarsening or material softening in the heat-affected zone becomes an important factor affecting the welding quality. Therefore, effective cooling of the weld and its surrounding areas is of great significance for improving the quality of the welded joint.

[0003] Currently, the cooling technologies for friction stir welding mainly include water cooling, gas cooling, and cooling substrates. Water cooling technology reduces the temperature by immersing or directly spraying cooling liquid in the weld area. Gas cooling uses high-pressure gas to spray the weld area to achieve temperature reduction through convective heat transfer. The cooling substrate is made of high-thermal-conductivity materials and contacts the welded part to conduct heat, and is usually used for cooling flat or regular-shaped workpieces. These technologies provide various solutions for the cooling of friction stir welding and have been widely used in actual welding.

[0004] However, the existing cooling methods can effectively reduce the temperature in the weld area, but there are still some problems in their actual applications. Specifically, traditional water cooling uses the method of immersing or spraying the coolant as a whole. During the cooling process, the temperature in the weld area and both sides gradually decreases. However, due to the heat concentration in the weld area, the cooling speed is slow, while the areas on both sides of the weld will quickly drop to the target temperature range under the action of the cooling medium. During this cooling process, a significant temperature difference is generated between the weld area (high-temperature area) and both sides (low-temperature area) due to the action of the cooling medium. The cooling speed of the weld area is slow (large thermal inertia), while both sides cool and shrink rapidly. This non-uniform cooling will cause thermal stress in the material. The shrinkage of the weld area lags behind that of both sides, and the rigid constraint on both sides will generate tensile stress (residual stress) in the weld. When it exceeds the yield strength of the material, microcracks may be induced, reducing the overall performance of the welded joint. Therefore, it is urgent to propose a new type of friction stir welding device to solve the above problems. Summary of the Invention

[0005] The purpose of the present invention is to provide a friction stir welding device capable of achieving gradient cooling control for the weld area and local areas around it.

[0006] The technical solution adopted by the present invention to solve the above problems is as follows: A friction stir welding device based on battery housing manufacturing, which is used for welding the seams between the assembled plates of the battery housing, and is characterized in that it includes:

[0007] A welding table, including a material placement plane for placing the plates.

[0008] A positioning mechanism, connected to the welding table to restrict the plate on the material placement plane when the welding device is in the working state.

[0009] A welding mechanism, which moves controllably and includes:

[0010] A rotating part, which rotates controllably.

[0011] A stirring part, connected to the rotating part to move therewith.

[0012] A cooling mechanism, connected to the welding mechanism, and the cooling mechanism includes:

[0013] A housing, with an accommodation space opened inside, and an opening, an air inlet, a liquid inlet and an exhaust port opened on the outer surface of the housing, and all three are communicated with the accommodation space.

[0014] A partition component, arranged in the accommodation space, and the partition component includes:

[0015] A number of parallel partition members, and the relatively facing side surfaces of adjacent partition members are configured to form a first heat dissipation channel when the opening is attached to the surface of the plate, surrounded by the surface of the plate and the inner wall of the housing, and the first heat dissipation channel is communicated with the air inlet, the exhaust port and the liquid inlet.

[0016] A liquid source, communicated with the liquid inlet to send the coolant into the first heat dissipation channel.

[0017] A blower, communicated with the air inlet to send air into the first heat dissipation channel.

[0018] Wherein, when the welding device is in the working state, the side of the housing with the opening is attached to the side of the plate restricted on the material placement plane away from the welding table, the opening covers the weld of the plate, and the partition component is located on the side of the weld of the plate to form a number of the first heat dissipation channels at a target distance from the weld of the plate.

[0019] Preferably, the air inlet and the exhaust port are arranged opposite to each other, and the center line connecting the two is configured to be parallel to the extending direction of the weld of the plate when the welding device is in the working state.

[0020] Preferably, the separator is a partition board, and the separator is configured such that when the welding device is in a working state, the length direction of the partition board is parallel to the extending direction of the weld of the plate member.

[0021] Preferably, the liquid inlet is opened on the opposite side of the housing and the opening, and the liquid inlet is configured such that when the welding device is in a working state, it is disposed opposite to the weld of the plate member.

[0022] Preferably, the exhaust port is configured such that when the welding device is in a working state, it is located between the liquid inlet and the opening.

[0023] Preferably, the number of the partition components is two groups. The two groups of partition components are configured such that when the welding device is in a working state, they are respectively located on both sides of the weld of the plate member, and the opposite sides of the two groups of partition components and the inner wall of the housing and the side of the plate member facing away from the welding table enclose a second heat dissipation flow path.

[0024] The second heat dissipation flow path is communicated with the air inlet, the exhaust port and the liquid inlet.

[0025] Preferably, communication grooves are formed on each of the separators, and the distances from the communication grooves on each of the separators in the partition component to the opening are configured such that when the welding device is in a working state, they decrease in sequence with the distances of the separators from the second heat dissipation flow path.

[0026] The friction stir welding device further includes:

[0027] An injection mechanism, which operates in a controlled manner. The injection mechanism is connected to the liquid source and the liquid inlet to control the amount of the coolant entering the liquid inlet.

[0028] Preferably, the number of the liquid inlets is several, and each of the liquid inlets is communicated with the second heat dissipation flow path and each of the first heat dissipation flow paths in a one-to-one correspondence.

[0029] The welding device further includes:

[0030] An injection mechanism. The number of the injection mechanisms is several. Each of the injection mechanisms is communicated with the liquid source, and each of the injection mechanisms is connected to each of the liquid inlets in a one-to-one correspondence to inject a fixed amount of the coolant into the second heat dissipation flow path and each of the first heat dissipation flow paths respectively when the welding device is in a working state.

[0031] Wherein, when the welding device is in a working state, the coolant injection amounts of the injection mechanisms are configured such that the coolant injection amounts of the first heat dissipation channels are all less than the coolant injection amount of the second heat dissipation channel, and the coolant injection amounts in the first heat dissipation channels decrease successively with the distance from the first heat dissipation channels to the second heat dissipation channel.

[0032] Preferably, the number of the air inlets is several, and each of the air inlets is in one-to-one correspondence and communication with the second heat dissipation channel and each of the first heat dissipation channels.

[0033] The number of the fans is several, and each of the fans is in communication with each of the air inlets in a one-to-one correspondence manner.

[0034] Advantages of the embodiments in the present invention:

[0035] Due to adopting a cooling mechanism composed of a housing, a partition component, a liquid source and a wind mechanism, and using the technical means that the partition component forms a plurality of first heat dissipation channels at a position away from the weld of the plate, effectively solving the problems of significant temperature difference, residual stress and microcracks caused by uneven cooling rates between the weld area and the two side areas during the welding process in the prior art, and then realizing uniform cooling of the weld and its surrounding areas, improving the overall quality and welding performance of the welded joint.

[0036] Due to adopting the technical means that the air inlet and the exhaust port are oppositely arranged, and the central connection line between the two is parallel to the extension direction of the weld of the plate, when the welding device is in a working state, the cooling air flow can flow uniformly along the extension direction of the weld, firstly pre-cooling the downstream of the weld (i.e., the area to be welded) and its surrounding areas, thereby reducing the temperature difference between the high-temperature weld area and the low-temperature area. This technical means effectively solves the problems of uneven temperature distribution, heat stress and residual stress concentration during the welding process in the prior art, and then realizes the technical effects of inhibiting grain coarsening, avoiding material softening, improving the microstructure and mechanical properties of the welding area, and improving the overall quality and stability of the welded joint. Description of the Drawings

[0037] Figure 1 is a schematic structural diagram of a friction stir welding device in an embodiment of the present invention.

[0038] Figure 2 is the present invention Figure 1 an enlarged view of part A.

[0039] Figure 3 is a schematic side sectional view of a friction stir welding device in an embodiment of the present invention.

[0040] Figure 4 is the present invention Figure 3 an enlarged view of part B.

[0041] Figure 5 It is a schematic structural diagram of a welding mechanism when the friction stir welding device is in a working state in an embodiment of the present invention.

[0042] Figure 6 It is a schematic cross-sectional view of a temperature reduction mechanism when the friction stir welding device is in a working state in an embodiment of the present invention.

[0043] Figure 7 is the present invention Figure 6 The enlarged view of part C.

[0044] Figure 8 It is a schematic structural diagram of a temperature reduction mechanism when the friction stir welding device is in a working state in an embodiment of the present invention.

[0045] Wherein: 10, plate member; 20, welding table; 210, material placement plane; 30, positioning mechanism; 40, welding mechanism; 410, rotating part; 420, stirring member; 50, temperature reduction mechanism; 510, housing; 511, accommodation space; 512, opening; 513, liquid inlet; 514, air inlet; 515, exhaust port; 520, partition assembly; 521, partition member; 5211, communication groove; 60, first heat dissipation channel; 70, second heat dissipation channel. Detailed implementation manners

[0046] The following will further describe in detail the specific implementation manners of the present application in conjunction with the accompanying drawings and embodiments. The following embodiments are used to illustrate the present application, but are not used to limit the scope of the present application.

[0047] As Figure 1 and Figure 3 shown, in a preferred embodiment of the present application, a friction stir welding device manufactured based on a battery housing 510 is provided, which is used for welding and processing the seams of each joined plate member 10 that composes the battery housing 510. The welding device includes a welding table 20, a positioning mechanism 30, and a welding mechanism 40. Among them, the welding table 20 includes a material placement plane 210 for placing the plate member 10. The positioning mechanism 30 is connected to the welding table 20 to limit the plate member 10 on the material placement plane 210 when the welding device is in a working state. The welding mechanism 40 is controlled to move, and the welding mechanism 40 includes a rotating part 410 and a stirring member 420. Among them, the rotating part 410 is controlled to rotate, and the stirring member 420 is installed at the rotating part 410 to rotate synchronously with the rotating part 410.

[0048] Specifically, the material placement plane 210 is the main bearing surface of the plate member 10, which is used to provide a stable placement area to ensure precise positioning during the welding process. The welding table 20 is made of high-strength metal materials (such as aluminum alloy or stainless steel) and has excellent heat conduction performance for assisting heat dissipation. The plane part has a regular rectangular design, and its size is customized according to the specifications of the battery case plate member 10, and it can adapt to plate members 10 of various shapes. The welding table 20 is fixed on the working platform through the bottom support structure. Further, adjustable height support feet can also be equipped to facilitate adaptation to different operating environments. The welding table 20 and the material placement plane 210 provide a reference for the stable welding of the plate member 10, effectively avoiding position deviation caused by vibration or thermal expansion during the welding process.

[0049] The positioning mechanism 30 is connected to the welding table 20 and is mainly used to fix the plate member 10 when the friction stir welding device is working. The positioning mechanism 30 adopts a multi-point clamping device, including a positioning fixture and a guide rail, and its power source can adopt equipment such as a cylinder or a motor. The positioning mechanism 30 is made of a heat-resistant and wear-resistant alloy material, and the contact surface of the clamping jaw can be covered with a flexible material (such as silicone rubber) to avoid scratching or indentation on the surface of the plate member 10 during the clamping process. The positioning mechanism 30 is installed on the edge of the welding table 20 through bolts or sliding rails, and its position can be adjusted according to the size of the plate member 10, and it is applicable to battery case plate members 10 of different specifications. The positioning mechanism 30 provides multi-point support during the welding process to prevent the plate member 10 from shifting or warping, and ensures that the weld line is consistent with the movement trajectory of the welding mechanism 40.

[0050] The welding mechanism 40 is the core part of this device to achieve friction stir welding, and it is composed of a rotating part 410, a stirring part 420, and a control system that works in cooperation with them.

[0051] The rotating part 410 is the driving core of friction stir welding. It is driven by a high-precision servo motor and is connected to the stirring part 420 through a main shaft to achieve the efficient rotation of the stirring part 420. Among them, the main shaft is made of heat-resistant and wear-resistant materials to ensure reliable operation in a high-friction environment. A high-precision bearing assembly is arranged outside the main shaft to provide stable rotational support and reduce the impact of vibration on the welding quality. The rotating part 410 provides stable rotational power, efficiently transmits the torque of the servo motor to the stirring part 420, and this design also supports the precise positioning and high-frequency rotation of the stirring part 420 during the welding process to ensure the consistency of welding quality. Further, the rotating part 410 can also be equipped with built-in sensors for real-time monitoring of the rotational speed and torque to ensure the stability of the welding process.

[0052] The stirring member 420 is a key working component of the welding mechanism 40. Its head is designed with a specific geometric shape to adapt to different materials and welding requirements. The stirring member 420 is made of a high-strength wear-resistant alloy material, has excellent high-temperature resistance, and can withstand long-term high-temperature friction. Moreover, the head structure of the stirring member 420 is designed to be replaceable according to welding applications, facilitating optimization and adjustment for different workpieces.

[0053] The control system is the "brain" of the welding mechanism 40, which performs precise motion control and real-time monitoring on the rotating part 410 and the stirring member 420. The control system includes the control of the servo module, the control of the motion unit, the cooperation with the sensing and monitoring module, and the human-machine interaction interface. Among them, the control of the servo module can control the rotation speed, torque, and direction of the servo motor of the rotating part 410, and can also ensure that the stirring member 420 works according to the preset trajectory and speed. Further, the control of the motion control unit can also coordinate the horizontal movement, vertical pressing force, and displacement of the welding mechanism 40 to ensure the accuracy of the weld trajectory.

[0054] In the prior art, the cooling technologies for friction stir welding mainly include water cooling, gas cooling, and cooling substrates, etc. However, although the existing cooling methods can reduce the temperature of the weld area, there are still some problems in their actual applications. When using traditional cooling methods, due to the excessive difference in the temperature change rate between the weld and its surrounding areas, tensile stress is likely to be generated in the welded joint area. When it exceeds the material yield strength, microcracks may be induced, thereby reducing the overall performance of the welded joint.

[0055] Different from the prior art, the friction stir welding device in this embodiment further includes a temperature reduction mechanism 50, a liquid source (not shown in the figure), and a blower (not shown in the figure), as Figures 2 - 8 described. Among them, the temperature reduction mechanism 50 is connected to the welding mechanism 40 to move synchronously with the welding mechanism 40. The temperature reduction mechanism 50 includes a housing 510 and a partition component 520. An accommodation space 511 is formed inside the housing 510. An opening 512, a liquid inlet 513, an air inlet 514, and an exhaust port 515 are formed on the outer surface of the housing 510, and all three are communicated with the accommodation space 511. The partition component 520 is arranged in the accommodation space 511. The partition component 520 includes a plurality of partition members 521 arranged in parallel. The relatively facing side surfaces of adjacent partition members 521 are configured to form a first heat dissipation channel 60 with the surface of the plate member 10 and the inner wall of the housing 510 when the opening 512 is attached to the surface of the plate member 10, and the first heat dissipation channel 60 is simultaneously communicated with the air inlet 514, the exhaust port 515, and the liquid inlet 513. The liquid source is communicated with the liquid inlet 513 to send the coolant into the first heat dissipation channel 60. The blower is communicated with the air inlet 514 to send air into the first heat dissipation channel 60.

[0056] When the welding device is in the working state, the housing 510 will move to the starting position (the starting point of the weld seam) under the action of a driving mechanism such as the aforementioned robotic arm, and the side of the housing 510 with the opening 512 will be attached to the side of the plate 10 restricted on the material placement plane 210 and facing away from the welding table 20. Moreover, the opening 512 covers the weld seam of the plate 10, and the partition assembly 520 is located on the side of the weld seam of the plate 10 to form a number of first heat dissipation channels 60 at a target distance from the weld seam of the plate 10.

[0057] Specifically, the cooling mechanism 50 moves synchronously with the welding mechanism 40, so as to rapidly cool the weld seam and the surrounding area within a short time after the stirring member 420 moves along the joint of the plate 10 to form the weld seam. This cooling can greatly shorten the residence time of the weld seam area in the high-temperature state, thereby reducing the phenomena of grain coarsening and softening caused by long-term high-temperature action, maintaining or restoring the original hardness of the material. Therefore, timely cooling helps to inhibit the excessive growth of grains in the weld seam area and promote the formation of fine and uniform grains. And the fine-grained structure usually has higher hardness and strength, so the mechanical properties of the weld seam can be effectively restored to achieve the purpose of promoting the hardness recovery of the weld seam. Moreover, by installing a number of partition members 521 in the housing 510 to form a plurality of first heat dissipation channels 60, gradient cooling of the weld seam and the area around the weld seam can also be realized.

[0058] Among them, the housing 510 is used to accommodate and limit the flow area of the coolant, thereby restricting the cooling range of the cooling mechanism 50. The housing 510 is embodied as an approximately rectangular box in a specific manner, with a hollow interior, which is the accommodation space 511. The housing 510 is fixedly connected to the welding mechanism 40 through a connecting member. One side of the rectangular box is in an open state, and this open side is the opening 512. The open side must face the plate 10 restricted on the material placement plane 210 during the working state (i.e., during welding) and be attached to the side of the plate 10 facing away from the welding table 20. Further, in some embodiments, sealing fillers can also be installed at the edge of the open side to fill the gap when the open side is attached to the plate 10, preventing the coolant injected into the accommodation space 511 from seeping out through the gap, so as to ensure that the cooling effect is concentrated on the weld seam and its surrounding area.

[0059] The partition member 521 is fixedly installed in the accommodating space 511 of the housing 510. The partition members 521 are arranged in parallel. The partition member 521 is embodied as a strip-shaped partition in a specific manner. The width direction of the partition is the same as the height direction of the housing 510, that is, when welding, the width of the partition is perpendicular to the material placement plane 210. And, in order to achieve the relative independence of each first heat dissipation channel 60, the side of the partition member 521 on the side away from the opening 512 in the width direction is closely attached to and hermetically connected to the inner wall of the housing 510 on the side away from the opening 512, and the other side of the partition member 521 in the width direction is flush with the plane of the opening 512 of the housing 510 (the open side of the housing 510). The length of the partition is parallel to the length direction of the housing 510, that is, the length of the partition is parallel to the extending direction of the weld of the plate member 10 on the material placement plane 210. Similarly, in order to ensure the relative independence of each first heat dissipation channel 60 and prevent the coolant in each first heat dissipation channel 60 from leaking to each other, both sides of the partition in the length direction are closely attached to and hermetically connected to the inner side wall of the housing 510. Further, in order to avoid affecting the contact area between the coolant and the surface of the plate member 10 and reduce the excessive occupancy area of the partition on the surface of the plate member 10, the thickness of the partition should be controlled within 0.5 mm or even smaller. The specific thickness of the shelf should be determined according to the actual weld size.

[0060] The first heat dissipation channel 60 provides a retention space for the coolant and the gas. With the cooperation of the gas at a certain flow rate and a certain amount of coolant, the specific area (the area corresponding to the first heat dissipation channel 60) around the weld can be controlled to cool down. Especially under the action of a specific amount of coolant and a specific rate of air flow, the cooling range of the area around the weld can be obtained through experimental detection or calculation. Therefore, when multiple first heat dissipation channels 60 are arranged in parallel, only by strictly controlling the injection amount of the coolant and the gas flow rate in different heat dissipation channels, the temperature reduction range can be controlled within a certain range. Therefore, the temperature reduction mechanism 50 only needs to control the air flow rate and the coolant injection amount according to the corresponding parameters obtained from the experiment to control the temperature reduction range of each first heat dissipation channel 60, so as to achieve the gradient cooling of the weld and the surrounding area and avoid large temperature changes between the area around the weld and the adjacent area.

[0061] Further, in order to facilitate the injection of the coolant, the introduction of the air flow and the discharge of the gas-liquid mixture, the liquid inlet 513 is opened on the side of the housing 510 away from the opening 512 (the side opposite to the opening 512), and the air inlet 514 and the exhaust port 515 are respectively opened on the side of the housing 510 (when the welding device is in the working state) perpendicular to the extending direction of the weld. And, it is also necessary to ensure the connectivity between the liquid inlet 513, the air inlet 514 and the exhaust port 515 and each first heat dissipation channel 60.

[0062] In this embodiment, when the friction stir welding device is in the working state, the plate 10 is placed on the material placement plane 210 and fixed by the positioning mechanism 30 to ensure that it does not displace during the welding process. During the welding process, the rotating part 410 of the welding mechanism 40 drives the stirring part 420 to move in the first direction and performs friction stir welding at the weld interface. The movement path and speed of the rotating part 410 are precisely controlled by the control system to ensure the strength and consistency of the welded joint. The cooling mechanism 50 moves synchronously with the welding mechanism 40. The coolant enters the accommodating space 511 through the liquid inlet 513 and is guided by the partition member 521 of the partition assembly 520 to flow into each first heat dissipation channel 60, and together with the air flow, performs gradient cooling on the weld area and the surrounding area. Therefore, this device is applicable to the butt welding scenario of the battery housing 510, especially suitable for application environments with high requirements for welding strength and weld quality.

[0063] In this embodiment, due to the adoption of the cooling mechanism 50 composed of the housing 510, the partition assembly 520, the liquid source and the air mechanism, and by using the technical means that the partition assembly 520 forms a plurality of first heat dissipation channels 60 at the weld of the plate 10, therefore, the problems of significant temperature difference, residual stress and microcracks caused by uneven cooling rates between the weld area and the two side areas during the welding process in the prior art are effectively solved, the local cooling gradient control of the weld area and the surrounding area is realized, the uniform cooling of the weld and its surrounding area is ensured, and the overall quality and welding performance of the welded joint are improved. Further, for the technical feature that "a number of first heat dissipation channels 60 are arranged in parallel on one side of the weld", the parallel arrangement of each first heat dissipation channel 60 enables each channel to work independently, facilitating the realization of local and customized cooling of the weld and its surrounding area by adjusting the cooling parameters of each channel. Moreover, by precisely controlling the coolant injection volume and air flow rate in each channel, the cooling rate around the weld can be accurately controlled as needed. The parallel arranged heat dissipation channels can form a continuous cooling zone in the weld and its surrounding area. This design can achieve more precise temperature control and cooling effect according to different weld sizes and process requirements.

[0064] In order to ensure the fluidity of the air flow in the first heat dissipation channel 60, in some embodiments, the air inlet 514 and the exhaust port 515 are arranged opposite to each other, and the air inlet 514 and the exhaust port 515 are configured such that when the friction stir welding device is in the working state, the center line connecting the two is parallel to the extension direction of the weld of the plate 10.

[0065] Specifically, the air inlet 514 and the exhaust port 515 are respectively opened on opposite sides of the housing 510, that is, on both sides of the housing 510 in the direction of the weld seam extension (when the friction stir welding device is in the working state). When the friction stir welding device is in the tooling state, the housing 510 moves along the direction of the weld seam extension of the plate 10 restricted on the placement plane 210 with the welding mechanism 40. The air inlet 514 and the exhaust port 515 are opened on both sides of the housing 510 perpendicular to the direction of the weld seam extension at this time, and the exhaust port 515 is located downstream of the air inlet 514, that is, the direction from the air inlet 514 to the exhaust port 515 is the same as the moving direction of the housing 510. That is, when the friction stir welding device is in the working state and the housing 510 moves along the direction of the weld seam extension, the direction from the air inlet 514 to the exhaust port 515 is consistent with the moving direction of the housing 510. The air inlet 514 and the exhaust port 515 are connected to an external air source and an air flow discharge system through pipes to form a complete air flow circulation channel.

[0066] The air inlet 514 is responsible for introducing cooling air flow (such as gas or a mixture of gas and coolant) into the interior of the housing 510. These gases will be mixed with the coolant when flowing through the first heat dissipation channel 60 and provide the necessary cooling effect for the welding area.

[0067] The exhaust port 515 discharges the coolant mixed gas or gas out of the housing 510 to ensure that the air flow leaves the welding area unobstructed. The exhaust port 515 is located downstream of the air inlet 514, forming a natural flow direction of the air flow, so that the cooling air flow evenly covers the weld area.

[0068] When the friction stir welding device starts to work, the air inlet 514 introduces cooling gas through an external air source. This gas enters the first heat dissipation channel 60 inside the housing 510 and keeps the same direction as the coolant flow direction. The cooling gas is mixed with the coolant and flows in the first heat dissipation channel 60 to form a stable air flow, and this air flow takes the coolant out of the housing 510.

[0069] However, since the air inlet 514 and the exhaust port 515 are oppositely arranged on both sides of the housing 510, and the flow direction from the air inlet 514 to the exhaust port 515 is the same as the moving direction of the housing 510 along the direction of the weld seam extension, when the housing 510 moves along the direction of the weld seam extension, the cooling air flow will first blow to the welding area and the area to be welded in front of the weld seam. When the gas mixed with the coolant forms a cooling air flow above the welding area, it can help the weld to cool quickly, thereby reducing the grain coarsening and material softening phenomena in the heat affected zone. And when the cooling air flow further flows forward to the area to be welded located downstream of the housing 510, it can pre-cool the area to be welded, that is, preliminarily cool the weld being formed downstream of the housing 510. Specifically, this pre-cooling effect can bring the following effects:

[0070] First, the temperature gradient can be controlled to reduce thermal stress and residual stress. Pre-cooling lowers the temperature of the area to be welded before welding, thus narrowing the temperature difference between the high-temperature weld zone and the surrounding low-temperature areas. This reduction in temperature difference can effectively reduce thermal stress and residual stress caused by uneven heating and cooling, and reduce microcracks or other welding defects that may occur due to stress concentration.

[0071] Second, it inhibits grain coarsening and material softening. During the welding process, high temperatures can cause problems such as grain coarsening and material softening in the heat-affected zone. Pre-cooling the downstream area in advance can keep the area to be welded at a lower temperature during welding, thereby reducing the high-temperature exposure time and avoiding excessive grain growth and softening, helping to maintain or restore the original hardness and strength of the material.

[0072] Next, it can also improve the microstructure of the welding area and the weld quality. Because pre-cooling makes the temperature drop of the weld and its surrounding area formed by subsequent welding more uniform, which helps to form a fine and uniform grain structure. This optimized microstructure usually corresponds to higher mechanical properties and better durability, thus improving the overall quality of the entire welded joint.

[0073] Finally, pre-cooling can also shorten the cooling time and improve process stability. By pre-cooling the downstream area, the welded area can quickly enter the appropriate temperature range after welding, reducing the adverse effects caused by long-term high-temperature exposure. At the same time, it also helps to shorten the cooling cycle and improve the stability and production efficiency of the welding process.

[0074] In summary, pre-cooling the weld and its surrounding area that is being welded and formed downstream of the housing 510 not only helps to achieve a balanced temperature distribution, reduce thermal stress and residual stress generated during welding, but also inhibits grain coarsening and material softening, thus ensuring that the weld area has better microstructure and mechanical properties, and ultimately improving the overall quality and reliability of the welded joint.

[0075] This embodiment can effectively pre-cool the area in front of the welding area through the relative arrangement of the air inlet 514 and the exhaust port 515 and the flow direction design. This design cools the joints of the unwelded area in advance during the welding process, avoiding welding defects (such as thermal cracks, material softening, etc.) that may be caused by excessive local temperature. In addition, due to the reasonable layout of the air inlet 514 and the exhaust port 515, the cooling airflow can stably cover the entire welding area, especially in the later stage of welding, the exhaust port 515 discharges the airflow to help the welding area cool quickly, thereby improving the quality and overall performance of the welded joint. Therefore, this embodiment improves the cooling efficiency through the optimized airflow path and flow control system, ensures the hardness recovery of the welded joint and the stable formation of the microstructure. Compared with the traditional cooling method, the design of the air inlet 514 and the exhaust port 515 makes the cooling effect more uniform and rapid, thereby improving the overall welding quality. It solves the problems of excessive temperature gradient and uneven cooling in the traditional cooling method, improves the quality and overall efficiency of the welded joint, and has significant technical advantages.

[0076] In order to prevent the airflow entering the air inlet 514 from interfering with the injection of the coolant during the injection of the coolant into the first flow channel, in some embodiments, such as Figures 3 to 4 and Figure 8 As shown, the liquid inlet 513 is opened on the opposite side of the shell 510 and the opening 512, and the liquid inlet 513 is configured to be arranged opposite to the welding seam of the plate 10 when the friction stir welding device is in the working state.

[0077] Specifically, when the friction stir welding device is in operation, the side of the plate 10 that is limited at the material placement plane 210 and is away from the welding table 20 is taken as the bottom surface, and the liquid inlet 513 is located above the plate 10, that is, the liquid inlet 513 is arranged on the opposite side of the housing 510 and the opening 512. This design ensures that the coolant will not be disturbed by the airflow of the air inlet 514 when entering the interior of the housing 510.

[0078] The main function of the liquid inlet 513 is to inject the coolant into the shell 510 and enter the first heat dissipation channel 60 to provide the required cooling effect for the welding area. The coolant quickly takes away the heat from the welding area through the heat dissipation channel, preventing the welding area from overheating and reducing the heat affected area. The coolant enters the shell 510 through the liquid inlet 513 and acts on the welding area together with the airflow. Since the liquid inlet 513 is located above the plate 10, the coolant can flow evenly through the welding area after entering the shell 510, taking away the heat and preventing the welding area from overheating.

[0079] In this embodiment, since the liquid inlet 513 is located above the plate 10, the coolant can smoothly enter and flow through the welding area, thereby strengthening the thermal management of the welding area. During the welding process, the coolant can effectively take away the heat, prevent the temperature of the welding area from being too high, and effectively avoid problems such as material deformation and thermal cracks caused by overheating. This layout also improves the flow efficiency of the coolant and reduces the negative interference of the airflow on the flow of the coolant, thereby improving the quality and precision of the welded joint. Therefore, this embodiment effectively avoids the interference of the airflow on the coolant injection process by arranging the liquid inlet 513 on the opposite side of the shell 510 and the opening 512, and ensures that the liquid inlet 513 is located above the plate 10, thereby improving the flow stability and cooling effect of the coolant. This design not only optimizes the cooling effect of the welding area, but also improves the quality and overall performance of the welded joint.

[0080] In order to ensure a good heat dissipation effect of the cooling mechanism 50, the first heat dissipation channel 60 needs to have a certain accumulation effect on the coolant to prevent the coolant from being quickly discharged from the exhaust port 515. Therefore, in some embodiments, Figure 2 , Figure 6 and Figure 7 As shown, the exhaust port 515 is configured to be located between the liquid inlet 513 and the opening 512 when the friction stir welding device is in operation.

[0081] The liquid inlet 513 is opened on the side of the shell 510 opposite to the opening 512, and the exhaust port 515 is opened between the two. A certain amount of coolant can be accumulated in the first heat dissipation channel 60. It can be understood that the temperatures of the joints of different panels 10 are different during welding, so the final target temperature of the weld is also different, so the required amount of coolant needs to be determined according to the welding temperature of different types of panels 10, and issues such as air flow rate and gradient cooling must also be considered.

[0082] Specifically, the location of the exhaust port 515 ensures that the coolant can accumulate in the first heat dissipation channel 60 for a period of time and will not be discharged too quickly due to the effect of the airflow, thereby maintaining a sufficient amount of coolant to ensure the stability of the heat dissipation effect. The design of the location of the exhaust port 515 ensures that the coolant can be properly accumulated in the first heat dissipation channel 60 to prevent the coolant from being discharged from the channel too quickly. The role of accumulating coolant is to increase the residence time of the coolant in the channel, so that it can fully play the role of heat exchange and take away more heat from the welding area, thereby improving the cooling efficiency.

[0083] When the friction stir welding device is working, the liquid inlet 513 injects the coolant into the first heat dissipation channel 60. The coolant begins to flow into the channel and is synergistically affected by the air flow to take away the heat in the welding area. The exhaust port 515 is located between the liquid inlet 513 and the opening 512. After the coolant flows into the channel, a certain amount accumulates in the channel in front of the exhaust port 515. With this configuration, the flow rate of the coolant is controlled to prevent it from being discharged too quickly, thus ensuring that the coolant can stay in the channel for enough time during the welding process to fully exchange heat with the high temperature in the welding area.

[0084] Moreover, during the welding process, the temperature differences at the seams of different plates 10 will result in different final temperatures of the weld seams. To adapt to the welding temperatures of different seams, the flow rate and temperature of the coolant need to be adjusted according to the changes in the welding temperature. Through the design of accumulating the coolant, the system can flexibly adjust the injection amount of the coolant according to the temperature differences of different seams, thereby meeting the requirement of gradient cooling. Especially for the areas with higher weld seam temperatures, the amount of coolant may need to be increased to better control the temperature changes.

[0085] In this embodiment, by setting a reasonable position for the exhaust port 515, a certain amount of coolant can accumulate in the first heat dissipation channel 60, thereby increasing the residence time of the coolant and the heat exchange efficiency. This design not only optimizes the cooling effect but also can flexibly adjust the flow rate of the coolant according to different welding temperature requirements, ensuring that the temperature changes in the welding area are within a reasonable range, thus improving the welding quality. Compared with the prior art, this solution solves the problem of too fast coolant flow rate by precisely controlling the cooperation between the coolant and the air flow, effectively improving the cooling effect.

[0086] To perform gradient cooling on both sides of the weld seam area simultaneously, in some embodiments, as Figure 6 shown, the number of partition components 520 is two groups. The two groups of partition components 520 are configured to be located on both sides of the weld seam of the plate 10 respectively when the friction stir welding device is in the working state, and the opposite sides of the two groups of partition components 520 and the inner wall of the housing 510 and the side of the plate 10 facing away from the welding table 20 enclose to form a second heat dissipation channel 70. The second heat dissipation channel 70 is communicated with the air inlet 514, the exhaust port 515, and the liquid inlet 513.

[0087] Among them, the second heat dissipation channel 70 is directly covered on the weld seam area of the plate 10 when the welding device is in the working state, and the amount of the liquid inlet 513 leading to the second heat dissipation channel 70 should be greater than any amount leading to the first heat dissipation channel 60.

[0088] Specifically, two sets of partition components 520 effectively isolate the second heat dissipation channel 70 and guide the coolant to flow through the weld area of the plate 10. This design enables the temperature reduction process in the areas on both sides of the weld to have a gradient change, ensuring that the temperature difference on both sides of the weld is reasonably controlled. The second heat dissipation channel 70 is a closed area connected to the air inlet 514, the exhaust port 515, and the liquid inlet 513, so as to maintain the flow of air and coolant during operation, enabling it to effectively cool the weld of the plate 10. The coolant introduced into the second heat dissipation channel 70 through the liquid inlet 513 is in a relatively large amount, so as to better absorb heat and take away the high temperature in the weld area during the welding process, ensuring the strength and stability of the welded joint.

[0089] When the friction stir welding device enters the working state, the coolant enters the second heat dissipation channel 70 through the liquid inlet 513. Through the action of the partition components 520, the second heat dissipation channel 70 is accurately positioned in the weld area of the plate 10. The amount of coolant introduced through the liquid inlet 513 is relatively large, ensuring that the coolant can fully flow through the weld area and accumulate in the channel, taking away the heat in the weld area. In this way, the second heat dissipation channel 70 provides an effective heat exchange area for the coolant, thereby helping the temperature to gradually decrease.

[0090] In this embodiment, by arranging two sets of partition components 520 on both sides of the weld, the second heat dissipation channel 70 effectively distributes the coolant in the weld area, ensuring the high efficiency of the second heat dissipation channel 70. It not only guarantees the cooling effect on both sides of the weld, but also improves the flow efficiency of the coolant. The amount of coolant introduced through the liquid inlet 513 is relatively large, which helps to more effectively take away the heat generated during the welding process, especially in the high-temperature area. Through reasonable adjustment of the coolant amount, the cooling requirements during the welding of different plates 10 can be met, avoiding excessive high or low local temperatures, and ensuring the quality and strength of the welded joint under different welding conditions.

[0091] It should be noted that two sets of partition components 520 are installed in the housing 510, and the two sets of partition components 520 are respectively located on both sides of the weld, ensuring that the temperature difference on both sides of the weld is effectively managed. During the welding process, the temperature difference between the advancing side and the returning side (the side where the tangential direction of the rotation of the stirring member 420 is the same as the moving direction of the welding mechanism 40 during welding is called the advancing side, and the side where the rotation direction of the stirring member 420 is opposite to the moving direction of the welding mechanism 40 during welding is called the returning side) will have an important impact on the recovery strength of the weld. By optimizing the temperature control, especially through the gradient cooling of the second heat dissipation channel 70 and each first heat dissipation channel 60, the coolant can be accurately adjusted according to the temperature difference between the advancing side and the returning side. Specifically, the flow rate, flow velocity, and residence time of the coolant on the advancing side and the returning side are different, ensuring that the cooling process on both sides is not too drastic. In this way, the temperature difference formed on both sides of the weld helps to improve the strength and toughness of the welded joint.

[0092] The temperature difference between the advancing side and the returning side has an important influence on the stress distribution, hardness and toughness of the welded joint. Appropriate gradient cooling can gradually reduce the temperature difference, avoid the concentration of internal stress caused by excessive temperature difference on both sides, and thus improve the mechanical properties of the weld.

[0093] Under a suitable temperature gradient, the recovery strength of the weld is enhanced. The precise control of the coolant ensures that the weld will not crack or undergo thermal deformation due to local overheating or overcooling during the curing and cooling processes. This enables the welded joint to not only have higher strength and toughness but also better withstand subsequent working loads.

[0094] In this embodiment, by configuring two sets of partition components 520 and forming a second heat dissipation channel 70, this solution provides an effective gradient cooling method, enabling reasonable control of the temperature difference between the two sides of the weld during the welding process. The precise flow regulation of the coolant and the design of the cooling path help to improve the strength of the welded joint and reduce welding defects, especially in terms of the recovery strength of the weld. Compared with the prior art, this solution improves the accuracy of the cooling effect, optimizes the temperature control, and significantly improves the welding quality.

[0095] In one embodiment, the number of liquid inlets 513 is only one, as Figures 6 to 8 shown. Communication grooves 5211 are formed on each partition member 521, and the distance between the communication grooves 5211 on each partition member 521 in each partition component 520 and the opening 512 is configured such that when the friction stir welding device is in a working state, it decreases successively with the distance of each partition member 521 from the second heat dissipation channel 70. The friction stir welding device further includes an injection mechanism, and a liquid source is connected to the liquid inlet 513 through the injection mechanism to control the feeding amount of the coolant.

[0096] When the friction stir welding device is in a working state, the liquid inlet 513 is arranged to face directly the weld of the plate member 10. The coolant directly passes through the second heat dissipation channel 70 through this liquid inlet 513. When the height of the coolant in the second heat dissipation channel 70 reaches the height of the communication grooves 5211 on the partition member 521 that constitutes the second heat dissipation channel 70, the coolant flows into the two adjacent first heat dissipation channels 60 to the second heat dissipation channel 70. After that, the coolant successively passes through the communication grooves 5211 on each partition member 521 and flows into the adjacent first heat dissipation channels 60 until the injection amount of the coolant reaches the target amount. At this time, the coolant in each first heat dissipation channel 60 should exactly be flush with the inner wall of the communication groove 5211 on the side close to the plate member 10.

[0097] It should be noted that the opening positions of the communication grooves 5211 on each partition member 521 need to meet the design principle of being closer to the second heat dissipation channel 70 and farther from the plate member 10 (when the welding device is in the working state) and being farther from the second heat dissipation channel 70 and closer to the plate member 10 (when the welding device is in the working state), so as to ensure that the second heat dissipation channel 70 and the first heat dissipation channel 60 close to the second heat dissipation channel 70 can accumulate more coolant, making the temperature reduction amplitude of the plate member 10 area corresponding to the second heat dissipation channel 70 and the first heat dissipation channel 60 close to the second heat dissipation channel 70 larger, so as to achieve gradient cooling of the weld and its surrounding areas. Moreover, the height of the exhaust port 515 from the plate member 10 should be higher than the height of the communication groove 5211 on the partition member 521 constituting the second heat dissipation channel 70 from the plate member 10.

[0098] Specifically, the number of the liquid inlets 513 is configured as a single one, and the liquid inlet 513 is directly opposite to the weld area of the plate member 10, so that the coolant can directly flow into the second heat dissipation channel 70 and act on the weld area preferentially. Moreover, the liquid inlet 513 is connected to the liquid source through an injection mechanism, and the injection mechanism can accurately control the feeding amount of the coolant to ensure that the cooling effect meets the actual requirements.

[0099] Each partition member 521 is provided with a communication groove 5211, and these grooves play a guiding role after the coolant is injected to ensure that the coolant flows along a predetermined path. Specifically, the distance between the communication groove 5211 and the opening 512 decreases successively with the distance between the partition member 521 and the second heat dissipation channel 70. This means that the position of the communication groove 5211 of the partition member 521 closer to the second heat dissipation channel 70 is higher and farther from the plate member 10. While the communication groove 5211 of the partition member 521 farther from the second heat dissipation channel 70 is set lower and closer to the plate member 10.

[0100] The coolant enters the second heat dissipation channel 70 through the liquid inlet 513 and accumulates along the channel. When the height of the coolant reaches the height of the communication groove 5211 on the partition member 521, the coolant will flow into the first heat dissipation channel 60 adjacent to the second heat dissipation channel 70. This process is carried out step by step, and the coolant flows from the second heat dissipation channel 70 into the first heat dissipation channel 60 through the communication groove 5211, ensuring that the coolant can fully cover the weld area and enter the adjacent area through the communication groove 5211.

[0101] Until the injection amount of the coolant reaches the set target amount, the height of the coolant in each first heat dissipation channel 60 is exactly flush with the inner wall of the communication groove 5211 on the side close to the plate member 10.

[0102] During the coolant injection process, the coolant enters the second heat dissipation flow channel 70 from the liquid inlet 513. The coolant covers the weld area through the flow channel until it comes into contact with the communication groove 5211 on the partition member 521. As the coolant continues to be injected, the coolant in the second heat dissipation flow channel 70 will gradually accumulate to form a certain height. When the height of the coolant reaches the height of the communication groove 5211, the coolant will start to flow into the first heat dissipation flow channel 60 adjacent to the second heat dissipation flow channel 70 and will eventually be evenly distributed in each first heat dissipation flow channel 60. This process continues until the injected amount of coolant reaches the target amount, ensuring that the amount and height of the coolant in each flow channel meet the design requirements.

[0103] The design of the communication groove 5211 enables the coolant to flow between the second heat dissipation flow channel 70 and the adjacent first heat dissipation flow channel 60, thereby forming a temperature gradient in different regions. This design achieves a stronger cooling effect on the weld and its surrounding areas by allowing more liquid to accumulate in the area close to the second heat dissipation flow channel 70. This gradient cooling not only ensures the effective cooling of the weld but also enables the temperature of the plate member 10 to be more evenly distributed, avoiding welding defects caused by excessive temperature differences during the cooling process.

[0104] Specifically, by adopting a decreasing heat dissipation rate distribution in sequence, the second heat dissipation flow channel 70 (corresponding to the weld) has the fastest heat dissipation efficiency, and the closer the first heat dissipation flow channels 60 are to the weld, the higher the heat dissipation rate. As the distance from the weld increases, the heat dissipation rates of the heat dissipation flow channels decrease in sequence. The design of the heat dissipation efficiency decreasing from the weld to both sides has the following advantages:

[0105] Rapidly cool down according to the high-temperature characteristics of the weld. Since the temperature at the weld is the highest, adopting the highest heat dissipation rate can rapidly reduce the temperature of the weld area in the shortest time, shorten the high-temperature residence time, thereby effectively suppressing the excessive coarsening and softening of grains, locking the fine and uniform grain structure, and improving the hardness and strength of the weld area.

[0106] It can also form a gentle temperature gradient. The second heat dissipation flow channel 70 in direct contact with the weld adopts a higher heat dissipation rate, while the first heat dissipation flow channels 60 close to the weld but not in the direct weld area have a slightly lower heat dissipation rate, and it gradually weakens outward. This can enable a gentle temperature gradient to be formed in the weld and its surrounding areas, avoiding sharp thermal contraction caused by excessive local temperature differences, and thus effectively reducing the generation of thermal stress and residual stress.

[0107] Although the temperature in the area around the weld is relatively high, it is not as high as that of the weld itself, and the required cooling intensity is relatively moderate. Through a design of gradually decreasing cooling intensity, it can be ensured that the area in direct contact with the weld cools down more rapidly, while the cooling rate in the slightly farther area is moderate, and further decreasing towards the outside, forming a gradually changing cooling effect from the inside to the outside, so as to better coordinate the thermal shrinkage of the weld and the surrounding area and reduce the risk of tensile stress and microcracks caused by sudden temperature changes.

[0108] This design makes the cooling process more precise and balanced. It can not only quickly lock the microstructure at the weld and restore or maintain the original hardness, but also avoid excessive temperature differences and residual stresses generated around the weld due to too rapid cooling, thus overall improving the mechanical properties and service life of the welded joint.

[0109] Furthermore, in this design, the cooling channels closest to the weld adopt the highest heat dissipation rate, enabling the weld area to cool down rapidly; while the cooling channels farther away from the weld adopt a lower heat dissipation rate, thus delaying the cooling process of the surrounding area. Through this differential design, the cooling processes of the weld and the surrounding area can be more coordinated, avoiding excessive temperature differences. And during the overall cooling process, the temperatures of each area can tend to reach the preset target temperature within a similar time, thereby reducing the thermal stress and internal stress caused by sudden temperature changes. Moreover, by finely controlling the coolant injection volume, air flow rate, and heat dissipation area in each first heat dissipation channel 60, the cooling rates of each area can be further optimized. The cooling parameters obtained through experiments or calculations can be used to adjust the cooling system, enabling both the weld and the surrounding area to be cooled to within the target temperature range within a predetermined time and ensuring the stability of the overall quality of the welded joint.

[0110] Therefore, adopting the scheme of gradually decreasing cooling intensity can not only quickly cool down the weld to lock the microstructure, but also, under the overall coordination of the temperature drop with the surrounding area, enable the temperatures of the weld and the surrounding area to drop to near the same target temperature within a similar time, thus effectively reducing the risk of residual stress and microcracks caused by uneven temperature and further improving the overall quality of the welded joint.

[0111] It should be noted that the height of the exhaust port 515 should be higher than the height of the communication groove 5211 on the partition 521 constituting the second heat dissipation channel 70 from the plate member 10. This ensures that the accumulation of coolant will not affect the stability of the cooling process, and the exhaust port 515 can timely discharge excessive gas or coolant vapor when the coolant accumulates to a certain amount.

[0112] In summary, by configuring a single liquid inlet 513 and providing communication grooves 5211 on each partition member 521, this design effectively controls the flow path and accumulation amount of the coolant within the second heat dissipation channel 70 and its adjacent first heat dissipation channel 60. This structural design not only ensures a gradient cooling on both sides of the weld during the welding process, but also improves the cooling efficiency, as well as the strength and quality of the welded joint. Compared with the prior art, this technical solution provides a more precise temperature control and coolant flow design, effectively avoiding the problem of uneven cooling that may occur during the cooling process, and significantly improving the welding quality and precision.

[0113] In another embodiment, the number of liquid inlets 513 is several, and each liquid inlet 513 is in one-to-one correspondence and communication with the second heat dissipation channel 70 and each first heat dissipation channel 60. The friction stir welding device further includes a plurality of injection mechanisms. The number of injection mechanisms is several, and each injection mechanism is in communication with a liquid source, and each injection mechanism is connected to each liquid inlet 513 in one-to-one correspondence, so as to inject different amounts of coolant into the second heat dissipation channel 70 and each first heat dissipation channel 60 respectively when the friction stir welding device is in a working state. Among them, when the friction stir welding device is in a working state, the coolant injection amounts of each injection mechanism are configured such that the coolant injection amount of each first heat dissipation channel 60 is less than that of the second heat dissipation channel 70, and the coolant injection amounts in each first heat dissipation channel 60 decrease successively with the distance from the corresponding first heat dissipation channel 60 to the second heat dissipation channel 70. Also, when the friction stir welding device is in a working state, the height of the exhaust port 515 from the plate member 10 should be higher than the height of the coolant to be accumulated in the second heat dissipation channel 70 and the height of the coolant to be accumulated in each first heat dissipation channel 60.

[0114] Specifically, in this embodiment, the number of liquid inlets 513 is several. Each liquid inlet 513 is connected to the second heat dissipation channel 70 and the first heat dissipation channel 60 in one-to-one correspondence. This design ensures that each heat dissipation channel can independently and evenly receive the coolant, thereby better controlling the cooling effect. By adding multiple liquid inlets 513, different amounts of coolant can be injected in different regions, enabling refined temperature control according to the temperature requirements of different regions.

[0115] Regarding the configuration and function of the injection mechanism, the number of injection mechanisms corresponds to the number of liquid inlets 513. The friction stir welding device further includes several injection mechanisms. Each injection mechanism is connected to a liquid source and is in one-to-one correspondence with each liquid inlet 513. These injection mechanisms control the flow rate and distribution of the coolant, ensuring that the coolant injection amounts in different heat dissipation channels can be adjusted according to actual needs. When the friction stir welding device is working, each injection mechanism injects different amounts of coolant into the second heat dissipation channel 70 and each first heat dissipation channel 60 respectively.

[0116] Coolant injection volume and distribution in each flow channel. First, the injection volume configuration of the coolant is precisely controlled by the injection mechanism. When the friction stir welding device is in operation, the amount of coolant received by the second heat dissipation flow channel 70 is greater than that of each first heat dissipation flow channel 60. This is because the second heat dissipation flow channel 70 directly covers the weld area and requires more coolant to quickly absorb heat and effectively cool down. The amount of coolant received by the first heat dissipation flow channel 60 is relatively small to prevent excessive cooling while ensuring a smooth transition of the cooling effect.

[0117] The connection between the coolant and each flow channel. The injection volume of the coolant in each first heat dissipation flow channel 60 is negatively correlated with the distance from the corresponding first heat dissipation flow channel 60 to the second heat dissipation flow channel 70. That is, the farther the first heat dissipation flow channel 60 is from the second heat dissipation flow channel 70, the less the coolant injection volume. This design makes the coolant distribution more reasonable, avoiding waste caused by excessive coolant and ensuring precise control of the cooling process.

[0118] Moreover, the matching relationship between the liquid inlet 513 and the injection mechanism ensures that the coolant can be precisely distributed to each heat dissipation flow channel. By controlling the flow rate of each injection mechanism, the adjustment of the temperature gradient can be achieved between different heat dissipation flow channels, thereby effectively avoiding welding defects caused by uneven cooling.

[0119] Furthermore, due to the higher cooling requirement of the second heat dissipation flow channel 70, its injection volume is greater than that of each first heat dissipation flow channel 60, which helps to more effectively cool down the weld and its surrounding area during the welding process. The first heat dissipation flow channel 60 mainly plays an auxiliary cooling role to reduce the overheating of the area around the welding joint.

[0120] It can be understood that the position of the exhaust port 515 is higher than the height of the coolant that needs to be accumulated in the second heat dissipation flow channel 70 and the first heat dissipation flow channel 60. This design ensures that the accumulation of coolant will not excessively affect the normal cooling function of the heat dissipation flow channel, and at the same time ensures that the system can timely discharge the excess gas to maintain the stability of the cooling effect.

[0121] During the operation of the cooling mechanism 50 of the friction stir welding device, the liquid source needs to be sent into each liquid inlet 513 through the injection mechanism to start injecting the coolant. Each injection mechanism sends the coolant into the second heat dissipation flow channel 70 and each first heat dissipation flow channel 60 respectively. The amount of coolant in the second heat dissipation flow channel 70 is greater than that of each first heat dissipation flow channel 60 to ensure that the weld area can be sufficiently cooled. The first heat dissipation flow channel 60 adjusts the coolant injection volume according to the distance from the second heat dissipation flow channel 70 and the cooling requirement. And because the coolant injection volume is adjusted according to the distance of each flow channel and the temperature control requirement, during the welding process, the coolant can achieve more precise cooling according to the temperature difference in different areas. This refined temperature control method helps to improve the welding quality and ensure the strength and stability of the weld.

[0122] In this embodiment, more efficient cooling during welding is achieved through more efficient coolant distribution and precise control of the coolant injection volume according to the requirements of each flow channel. In particular, the coolant injection volume of the second heat dissipation flow channel 70 is relatively large, which can more effectively cool the weld area while avoiding problems such as overcooling or uneven temperature. Moreover, since the coolant injection volume in the second heat dissipation flow channel 70 is relatively large, the temperature of the weld area can drop rapidly, preventing welding defects caused by excessive thermal stress. The relatively small coolant volume in the first heat dissipation flow channel 60 ensures that the temperature change in the area around the welded joint is gentle, thus effectively avoiding excessive temperature difference and welding stress.

[0123] It should be noted that the heat dissipation efficiency in this embodiment also decreases successively from the weld to both sides, which has the same effect as the design in the previous embodiment with only one liquid inlet 513, and will not be elaborated here.

[0124] Furthermore, through the configuration of multiple injection mechanisms and the liquid inlet 513, the injection volume and distribution of the coolant can be flexibly adjusted according to different welding requirements, ensuring that the cooling effect of each flow channel can be optimized. This flexible design can meet the requirements of different materials, different thicknesses, and different welding processes, providing higher welding precision and better welding quality.

[0125] In summary, in this embodiment, by equipping the friction stir welding device with multiple liquid inlets 513 and multiple injection mechanisms, and precisely controlling the coolant injection volume of each heat dissipation flow channel, precise temperature control of the welding area can be achieved. Compared with the traditional cooling system, the design of this embodiment not only improves the cooling efficiency, optimizes the temperature control effect, but also avoids uneven cooling and the generation of welding defects, significantly improving the welding quality.

[0126] It should be noted that the above two embodiments (only one liquid inlet 513 and multiple liquid inlets 513) respectively describe the injection and distribution methods of the coolant in the friction stir welding device. Although they are different in design structure, the ultimate goal is to achieve precise cooling of the welding area and avoid the influence of too fast or too slow cooling on the welding quality. The following is a comparative analysis of the advantages and disadvantages of the two embodiments:

[0127] In the first embodiment, only a single liquid inlet 513 is designed, but through the communication groove 5211 on the partition 521, each first heat dissipation flow channel 60 can only accommodate the designed target volume of coolant, thereby achieving precise gradient cooling of the area around the weld.

[0128] The number of liquid inlets 513 in this embodiment is a single configuration, which simplifies the structure and operation of the system and reduces the complexity of components. By providing communication grooves 5211 on the partition 521 and designing according to the distance of the flow channels, it is possible to achieve the gradual injection and flow of the coolant in different regions. Guided by the communication grooves 5211, the coolant gradually flows into the second heat dissipation flow channel 70 and the first heat dissipation flow channel 60, realizing gradient cooling. This makes the cooling process more controllable and avoids welding defects caused by excessive temperature difference. The coolant enters the second heat dissipation flow channel 70 through the liquid inlet 513 and preferentially acts on the weld area, effectively avoiding overheating problems during the welding process. The injection volume and flow path of the coolant are precisely controlled by the design, so the temperature of the welding area can be controlled more effectively, avoiding too fast or too slow cooling.

[0129] However, although this embodiment has the above advantages, overall there is only a single liquid inlet 513, which may cause certain restrictions on the flow of the coolant. Especially in a large welding area or a complex welding structure, the uniformity of the coolant flow may be affected. Also, since the flow of the coolant depends on the relative height difference between the communication grooves 5211, some areas may cool more slowly, resulting in an unsatisfactory temperature control effect, especially when the flow channel design is more complex.

[0130] In the second embodiment, multiple liquid inlets 513 are designed to precisely control the injection volume of the coolant through the injection mechanism.

[0131] The configuration of multiple liquid inlets 513 and the injection mechanism in this embodiment enables the coolant to be precisely distributed to each flow channel, making the cooling effect more uniform. Each flow channel can receive different amounts of coolant according to needs, ensuring the accuracy of temperature control. Also, since the injection volume of the coolant can be independently controlled, it can be adjusted according to the temperature control requirements of different regions to meet the needs of different materials, thicknesses, and welding processes. For example, the second heat dissipation flow channel 70 (weld area) can receive more coolant, while the first heat dissipation flow channel 60 receives less coolant. And the precise temperature control design helps to better avoid problems such as overheating and excessive thermal stress during the welding process, thereby improving the strength and stability of the welded joint. The precise control of the coolant helps to achieve gradient cooling on both sides of the weld, reducing the temperature difference and avoiding welding defects caused by uneven cooling. The design of the position of the exhaust port 515 ensures that the accumulation of the coolant does not affect the cooling function of the heat dissipation flow channel, and can timely discharge excessive gas or coolant vapor, ensuring the stability and efficiency of the cooling system.

[0132] However, although the above-mentioned advantages are present in this embodiment, the configuration of multiple liquid inlets 513 and injection mechanisms increases the complexity of the system, and the manufacturing and maintenance costs may be relatively high. The multiple injection mechanisms and liquid inlets 513 require precise coordination and control, which may increase the technical difficulty during implementation. Moreover, to ensure that the flow rate of each liquid inlet 513 and injection mechanism can be precisely controlled, the system requires more complex sensors and control systems, which will increase the cost and maintenance difficulty of the system.

[0133] Therefore, after comprehensive consideration, the first embodiment is suitable for welding tasks with a relatively small scale and simple structure. Due to its relatively simple design and low cost, it is suitable for simple and standardized welding tasks, especially when the coolant flow path is relatively short. The second embodiment is suitable for complex welding tasks, especially those that require precise control of coolant distribution and temperature control, such as multi-pass welding, large plate 10, or welding of different materials. Although the cost and complexity are relatively high, it can provide higher precision and reliability.

[0134] Furthermore, in order to more precisely control the cooling amplitude and cooling rate of each flow channel (each first heat dissipation flow channel 60 and second heat dissipation flow channel 70) during operation, in some embodiments, the number of air inlets 514 is several, and each air inlet 514 is in one-to-one correspondence and communication with the second heat dissipation flow channel 70 and each first heat dissipation flow channel 60. The number of fans is several, and each fan is in communication with each air inlet 514 in a one-to-one correspondence manner.

[0135] Specifically, the number of air inlets 514 is several, and each air inlet 514 is connected to the second heat dissipation flow channel 70 and each first heat dissipation flow channel 60 in a one-to-one correspondence. This means that each flow channel has an independent air inlet 514, which helps to achieve more precise air flow control and ensure the cooling effect of each heat dissipation flow channel during operation. The several fans are connected to the corresponding air inlets 514 through pipes. The air flow sent by the fans combines with the coolant and jointly acts on the thermal management system in the heat dissipation flow channel. The air flow provides an additional heat exchange effect and enhances the cooling effect of the coolant. The air flow of the fans and the flow of the coolant form a complementary heat dissipation mechanism, further improving the cooling effect. Among them, the number of fans is the same as the number of air inlets 514, ensuring that each flow channel can receive separate air flow support, thereby avoiding air flow interference between multiple flow channels and improving the cooling efficiency and temperature control accuracy.

[0136] When the friction stir welding device is in the working state, each fan forcibly sends air or gas into the corresponding heat dissipation flow channel through the air inlet 514. Each fan adjusts the wind speed and air intake volume according to the requirements of the heat dissipation flow channel to achieve more precise and efficient temperature control.

[0137] Among them, the wind speed of each fan can be precisely adjusted by the control system to ensure that the cooling rate of each heat dissipation channel meets the requirements. For the second heat dissipation channel 70, this means a higher wind speed to quickly reduce the temperature of the welding area. While the wind speed of the first heat dissipation channel 60 is relatively low to avoid overcooling the surrounding area. Moreover, the use of the fan can dynamically adjust the air flow according to the actual welding temperature requirements, ensuring that the temperature change is stable and there will be no areas with too high or too low temperature, preventing welding defects caused by local overheating or uneven cooling.

[0138] In this embodiment, by introducing multiple fans and air inlets 514 and precisely controlling the flow rate and speed of the air flow, this embodiment can achieve more efficient and precise temperature control during the friction stir welding process. The combined design of the fan and the air inlet 514 enables the cooling process to be finely adjusted, providing the required cooling rate for different regions, thereby effectively optimizing the cooling effect of the coolant, improving the welding quality, and reducing welding defects.

[0139] In order to optimize the gradient heat dissipation effect of the cooling mechanism 50 on the weld and the surrounding area of the plate 10, a control method applicable to the friction stir welding device in the above-mentioned second embodiment (when the number of liquid inlets 513 is several and the communication groove 5211 is not provided on the partition member 521) is specifically proposed. This control method needs to achieve the following four goals simultaneously:

[0140] 1. Accelerate the cooling rate of the weld area and the area around the weld.

[0141] 2. Ensure that the cooling rate of the weld area (corresponding to the second heat dissipation channel 70) is greater than the cooling rate of both sides of the weld (corresponding to each first heat dissipation channel 60).

[0142] 3. Achieve gradient cooling along both sides of the weld area (the first heat dissipation channel 60), that is, the closer to the weld, the faster the cooling, and the farther away from the weld, the slower the cooling.

[0143] 4. Make each area (the weld area and the two side areas) reach the predetermined target temperature (such as the ambient temperature of 25°C or slightly higher than the ambient temperature of 50°C) in almost the same time.

[0144] To achieve the above goals simultaneously, the specific control scheme includes:

[0145] First, the overall control idea is as follows:

[0146] In this scheme, the cooling process in the cooling mechanism is divided into multiple "temperature control zones". Among them, the weld area corresponds to the second heat dissipation channel 70, which requires the highest cooling rate. The areas on both sides of the weld correspond to each first heat dissipation channel 60, which can be further divided into several sub-areas according to the distance from the weld, and the required cooling rate decreases in a gradient (that is, the closer to the weld, the faster the cooling, and the farther away from the weld, the slower the cooling).

[0147] The overall idea of the whole system is "partitioned set target cooling curve - multi-channel closed-loop feedback regulation - central coordinated control". By adjusting the coolant injection volume and air flow (fan speed, air flow direction) of each channel in real time, it is ensured that the cooling rate of each area not only meets the local requirements, but also enables each area to reach the target temperature simultaneously within a predetermined time, thus avoiding excessive temperature differences in each area from generating thermal stress and residual stress.

[0148] Secondly, the specific system composition includes:

[0149] Temperature sensing network. High-precision temperature sensors are arranged both in the weld area and on both sides of the weld to collect temperature data of each control area in real time. It should be noted that each temperature sensor should be installed in the second heat dissipation channel 70 and each first heat dissipation channel 60, and should be as close as possible to the surface of the plate 10 when the welding device is in working state to accurately reflect the temperature of the weld and the surrounding area.

[0150] Flow and air flow control device. Each heat dissipation channel is equipped with an independent coolant injection device (injection mechanism) and a matching adjustable valve, and at the same time, a separately or grouped controlled fan (or air flow regulating device) is configured to respectively control the coolant flow rate and air flow rate.

[0151] Central control unit. Using a PLC or an embedded microcontroller, integrating multiple PID (or a more advanced model predictive control, MPC) controllers, responsible for receiving sensor data of each area, calculating the control error and outputting coolant and air flow regulation instructions for each path, and at the same time realizing the coordination and dynamic compensation between each area.

[0152] Then, the detailed steps of the control method are as follows:

[0153] Preset target temperature curve and partition planning, including:

[0154] Target temperature setting. Preset the target temperature according to the process requirements (such as 25 °C or 50 °C), and set the time required to drop from the current highest temperature to the required time .

[0155] Area division and cooling curve planning. Set the weld area (second heat dissipation channel 70) as the "rapid cooling area", and further divide the areas on both sides of the weld (each first heat dissipation channel 60) into several sub-areas according to the distance from the weld (for example, the area close to the weld is the "medium-speed cooling area", and the outermost is the "low-speed cooling area"). And preset an ideal cooling curve for each area , requiring each area to smoothly drop to within Although the initial temperatures are different, synchronous arrival is achieved through cooling rate compensation.

[0156] Real-time data acquisition and error calculation. Sensors in each area collect temperature in real time (where represents each control area), and transmit the data to the central control unit. Calculate the control error for each area: . Where is the preset cooling target curve value for this area. Independent PID closed-loop regulation for each area. Configure an independent PID controller for each area, and its outputs include: coolant injection adjustment (used to adjust the injection flow rate of this area) and air flow (fan speed) adjustment (used to adjust the cooling air flow rate).

[0157] Control strategies, including:

[0158] For the weld area (the second heat dissipation channel 70), since the highest cooling rate is required, when the error is large (the temperature is too high), the PID controller outputs a large positive regulation signal, thereby increasing the coolant injection volume and increasing the air flow rate, enabling rapid local heat dissipation.

[0159] For the areas on both sides of the weld (the first heat dissipation channel 60), set gradient parameters for the control parameters according to the distance from the weld. The following method can be adopted: . Where is the distance of this channel from the weld. The closer to the weld is, the smaller it is, and the preset injection volume approaches ; the farther away, the preset injection volume decreases. Similarly, the air flow rate is also set according to a similar gradient relationship.

[0160] The PID controller adjusts the actual injection volume and fan speed according to the error of each area to compensate for the system response.

[0161] Next, central coordination and dynamic compensation are as follows:

[0162] Synchronous cooling target. Although the initial temperatures and heat dissipation capabilities of each area are different, the goal requires that each area reach simultaneously within .

[0163] The coordination logic is specifically that the central control unit regularly compares the temperature cooling processes of each area. If it is found that a certain area cools too fast or too slow, the following compensation is carried out:

[0164] If the temperature of the weld area drops too quickly (ahead of target), reduce the amount of coolant injected or the fan speed (or increase preheating compensation) appropriately. If the temperature of the areas on both sides of the weld drops too slowly (behind target), increase the amount of coolant injected and the airflow speed in the corresponding areas.

[0165] The above-mentioned dynamic coordination is achieved by adjusting the output reference value of the PID controller of each area or directly adjusting the preset gradient parameters of each channel.

[0166] Among them, the reference model can adopt a distributed model predictive control (MPC) method to predict the temperature change trend of each area based on the current temperature distribution, cooling equipment dynamics and welding head movement speed, and adjust the cooling parameters of each channel in advance, so that the temperature curve of each area converges to the preset target curve.

[0167] Furthermore, since the cooling mechanism and the welding mechanism 40 move synchronously along the plate 10, the system also needs to consider the effect of the welding head moving speed on heat conduction and pre-compensate for the lag caused by the movement. In front of the welding head (pre-cooling area), the fan speed can be appropriately increased in advance and the amount of coolant injection can be increased so that the area where the weld is about to be formed can be reduced to an appropriate temperature before welding, thereby shortening the overall cooling delay and ensuring that each area reaches the target temperature at the same time.

[0168] In this embodiment, after using the above control method, each key control node is implemented as follows:

[0169] To accelerate the cooling, when the temperature sensor detects a large deviation in the welding seam area (the second heat dissipation channel 70), the coolant flow rate and the air flow rate are quickly increased through the PID closed loop to achieve rapid heat dissipation.

[0170] Zone difference control, preset gradients of coolant and air flow in the two zones on both sides of the weld (by function It ensures that the area closer to the weld has a faster cooling rate, while the area farther from the weld has a slower cooling rate.

[0171] Synchronous cooling: the central coordination control unit compares the cooling progress of each area in real time and dynamically adjusts the output of each channel to ensure that each area drops to the target temperature within the predetermined time despite different local heat dissipation rates.

[0172] Closed-loop feedback and dynamic compensation, through the coordinated work of zone temperature acquisition, PID control and MPC prediction (or other advanced control algorithms), achieve rapid correction of temperature errors and ensure system stability, ensuring that the overall cooling process of the weld and surrounding areas is smooth and balanced.

[0173] The key to the control method in this embodiment is:

[0174] Partition setting and preset target curve, that is, pre-plan the cooling curve according to the different thermal characteristics of the weld and the areas on both sides thereof;

[0175] Multi-parameter closed-loop control.

[0176] Regulate the coolant injection volume and air flow rate respectively, and use independent PID loops to achieve local fine adjustment.

[0177] Central coordination dynamic compensation, by real-time monitoring and prediction of the temperature change trends in each area, coordinate the parameters of each channel to ensure that each area reaches the target temperature synchronously.

[0178] In summary, this control method can not only achieve rapid cooling in the weld area and gradient cooling in the areas on both sides, but also enable each area to cool down to the same target temperature within a predetermined time, so as to achieve the purpose of improving the quality of the welded joint, reducing thermal stress and residual stress. Moreover, by combining hardware (temperature sensors, adjustable valves, fan controllers) with software (central control algorithm, PID / MPC algorithms), this solution can flexibly adapt to different welding conditions and meet the four requirements of the cooling mechanism 50 in the friction stir welding device proposed in an embodiment of this application.

[0179] It should be noted that in the step of the above control method, "a temperature sensing network arranges high-precision temperature sensors in both the weld area and on both sides of the weld, for real-time collecting the temperature data of each control area." Since the temperature sensors installed in each heat dissipation channel should not be able to directly measure the temperature inside the weld and the temperature inside the areas on both sides of the weld. Therefore, in order to ensure that the temperature inside the weld area and the temperature inside the areas on both sides can ultimately be reduced to the target temperature, a temperature compensation scheme is hereby proposed to make up for the problem that the temperature sensors installed in each heat dissipation channel cannot directly measure the temperature inside the weld and its two sides. This scheme establishes the conversion relationship between the detected value of the temperature sensor and the actual internal temperature through three steps of experimental calibration, data modeling and online compensation, so as to achieve temperature compensation for different materials, different plate thicknesses, and when using their respective optimal welding parameters. The specific scheme is as follows:

[0180] For different materials and plate thicknesses, under the condition of using the corresponding optimal welding parameters (such as welding travel speed, rotational speed of the stirring member 420, downward pressure, etc.), conduct experimental welding. During the experiment, install (or embed) auxiliary temperature sensors inside the weld area and on both sides inside, and at the same time install conventional temperature sensors in the heat dissipation channels to collect the temperature data of the surface or adjacent areas. Then, compare the "internal temperature" data collected by the auxiliary sensors with the "surface or near-surface temperature" data detected by the heat dissipation channel sensors, and use statistical or regression methods to establish a mathematical model (such as a linear or non-linear regression model) to obtain the temperature difference compensation function between the two. This function will consider the influence of the thermal conductivity of the material, plate thickness, welding heat input, and other welding parameters.

[0181] During the actual welding process, the central control system calculates the estimated internal temperature using the compensation function established in advance based on the temperature collected in real time by the sensors in the heat dissipation flow channels. :

[0182] .

[0183] Among them, is the compensation value function, and the parameters include materials , plate thickness , welding parameters (such as welding speed, stirring speed, downward pressure, etc.) and the current detection value of the sensor .

[0184] Furthermore, to improve the accuracy, an online adaptive adjustment algorithm (such as adaptive filtering or online learning) can be adopted to continuously update the compensation function parameters using other reference temperatures collected periodically (such as the surface temperature monitored by infrared imaging), ensuring that the compensation effect adapts to the small fluctuations of the actual working conditions.

[0185] The specific implementation plan includes:

[0186] Select samples of different materials and plate thicknesses with representativeness and conduct test welding using the best welding parameters.

[0187] Embed micro thermocouples (or other suitable temperature sensors) inside the weld area and on both sides of the area to ensure that the internal temperature can be directly recorded. At the same time, install standard temperature sensors in each heat dissipation flow channel (i.e., the conventional installation position of the temperature sensors) to record the surface or near-surface temperature.

[0188] During the welding process, record the temperature curves of each measuring point changing with time, and pay attention to recording the welding parameters (welding speed, stirring speed, downward pressure, etc.), material properties (thermal conductivity, heat capacity, etc.) and plate thickness information. And obtain the internal temperature curve of the weld area , the surface (or near-surface) temperature curve of the weld area and the internal and surface temperature curves on both sides of the weld and .

[0189] Compare the internal temperature with the temperature detected by the sensor to obtain the temperature difference data: . And analyze the variation relationship of this temperature difference with time, temperature, materials, plate thickness, welding parameters, etc. to determine whether there is a linear or non-linear correlation.

[0190] Then, a more accurate compensation function is obtained by using a linear, polynomial or other non-linear model (even fitting with a neural network) as follows to fit the compensated temperature. Moreover, compensation models are established for the weld region and the regions on both sides respectively. Note that due to different heat conduction and cooling conditions in different regions, there may be differences in their compensation coefficients.

[0191] Next, cross-validation is performed on the model using some of the test data to check the estimated internal temperature. The error between the estimated internal temperature and the actually measured internal temperature is checked to ensure that the compensation accuracy meets the process requirements.

[0192] Finally, in the central control unit, according to the welding material, plate thickness and current welding parameters, the corresponding compensation function is called to perform compensation calculation on the temperature collected by the sensors in the heat dissipation flow channel in real time. The estimated internal temperature is obtained. .

[0193] Furthermore, it can also be compared with the preset target temperature curve to calculate the error and feedback it to the cooling system (adjust the coolant injection amount, air flow rate, etc.) to ensure that the actual internal temperature reaches the target temperature as soon as possible. Moreover, if conditions permit, an online correction algorithm can be further introduced. Using, for example, the surface temperature monitored by periodic infrared thermography or some internally temperature data that can be repeatedly collected, the parameters of the compensation model are finely adjusted so that the control system can adapt to the small parameter changes of the environment and the workpiece during the welding process.

[0194] Therefore, by adopting the above solution, the internal temperature of the weld region and the regions on both sides of the weld under different materials, plate thicknesses and different welding conditions can be effectively estimated, and the cooling strategy can be adjusted accordingly, so as to ensure that the final temperature of each region can reach the expected target temperature.

[0195] The above content described in this specification is only an example of the present invention. Those skilled in the art of the present invention can make various modifications or supplements to the described specific embodiments or use similar methods for substitution, as long as they do not deviate from the content of this specification of the present invention or exceed the scope defined by this claims, they should all fall within the protection scope of the present invention.

Claims

1. A friction stir welding device based on battery shell manufacturing, used for welding the seams between the assembled panels of the battery shell, characterized in that: include: The welding table includes a material placement plane for placing the plate; A positioning mechanism connected to the welding table to restrict the plate to the material placement plane when the welding device is in working state; Welding mechanism, controlled movement, comprising: The rotating part rotates in a controlled manner; A stirring member connected to the rotating part to move therewith; A cooling mechanism is connected to the welding mechanism, and the cooling mechanism comprises: A shell, wherein an accommodating space is provided inside the shell, and an opening, an air inlet, a liquid inlet, and an exhaust port are provided on an outer surface of the shell, and all of the four ports are connected to the accommodating space; A partition assembly is arranged in the accommodating space, and the partition assembly includes: A plurality of parallel partitions, wherein the side surfaces of adjacent partitions facing each other are configured to form a first heat dissipation channel together with the surface of the plate and the inner wall of the shell when the opening is in contact with the surface of the plate, and the first heat dissipation channel is connected with the air inlet, the exhaust port and the liquid inlet; a liquid source, connected to the liquid inlet, to deliver cooling liquid into the first heat dissipation channel; a fan, connected to the air inlet, to flow air into the first heat dissipation channel; The liquid inlet is opened on a side of the shell away from the opening, and the liquid inlet is configured to be arranged toward the plate weld when the welding device is in a working state; The number of the partition components is two groups, and the two groups of partition components are configured to be located on both sides of the plate weld when the welding device is in a working state, and the opposite sides of the two groups of partition components are surrounded by the inner wall of the shell and the surface of the plate to form a second heat dissipation channel; The second heat dissipation channel is in communication with the air inlet, the exhaust port and the liquid inlet; Wherein, when the welding device is in working state, the side of the shell having the opening is in contact with the side of the plate restricted on the material placement plane away from the welding table, the second heat dissipation channel cover is arranged at the plate weld, and the partition assembly is located on the side of the plate weld, so as to form a plurality of the first heat dissipation channels at a target distance from the plate weld; The coolant injection amount of each of the first heat dissipation channels and the second heat dissipation channels is configured such that the coolant injection amount of the second heat dissipation channels is greater than the coolant injection amount of each of the first heat dissipation channels, and the coolant injection amount of each of the first heat dissipation channels decreases successively as the distance between the first heat dissipation channels and the second heat dissipation channels increases.

2. A friction stir welding device for manufacturing a battery shell according to claim 1, characterized in that: The separator is a partition plate, and the separator is configured so that when the welding device is in a working state, the length direction of the partition plate is parallel to the extension direction of the plate weld.

3. According to a friction stir welding device manufactured based on a battery shell as claimed in claim 1, the exhaust port is configured to be located between the liquid inlet and the opening when the welding device is in a working state.

4. A friction stir welding device for manufacturing a battery shell according to claim 1, characterized in that: A connecting groove is formed on each of the partitions, and the distance from the connecting groove to the opening on each of the partitions in the partition assembly is configured to decrease in sequence as the distance from each of the partitions to the second heat dissipation channel increases when the welding device is in a working state; The friction stir welding device also includes: The injection mechanism operates in a controlled manner, and the injection mechanism connects the liquid source and the liquid inlet to control the amount of cooling liquid entering the liquid inlet.

5. A friction stir welding device for manufacturing a battery shell according to claim 1, characterized in that: The number of the liquid inlets is several, and each of the liquid inlets is connected to the second heat dissipation flow channel and each of the first heat dissipation flow channels in a one-to-one correspondence; The welding device also includes: Injection mechanisms, the number of which is several, each of which is connected to the liquid source, and each of which is connected to each of the liquid inlets in a one-to-one correspondence, so as to respectively inject a certain amount of coolant into the second heat dissipation flow channel and each of the first heat dissipation flow channels when the welding device is in a working state; Wherein, when the welding device is in working state, the coolant injection amount of each injection mechanism is configured so that the coolant injection amount of each first heat dissipation channel is smaller than the coolant injection amount of the second heat dissipation channel, and the coolant injection amount in each first heat dissipation channel decreases successively with the distance from the first heat dissipation channel to the second heat dissipation channel.

6. A friction stir welding device for manufacturing a battery shell according to claim 5, characterized in that: The number of the air inlets is several, and each of the air inlets is connected to the second heat dissipation flow channel and each of the first heat dissipation flow channels in a one-to-one correspondence; The number of the fans is several, and each fan is connected to each air inlet in a one-to-one correspondence.

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