Welding workstation for vehicle battery tray

Abstract

The embodiment of the invention discloses a welding workstation for a vehicle battery tray. According to one specific implementation mode, the welding workstation comprises welding equipment, a carrying robot and a controller, the welding equipment comprises a welding robot and a workbench, and the welding robot is located in the middle section of the workbench; the two sides of the workbench are each provided with a sliding station. Each sliding station is provided with a positioner; a sliding rail is arranged below the transfer robot; the controller is in communication connection with the welding equipment and the carrying robot; the controller is configured to execute the following steps that the carrying robot is controlled to carry a workpiece to a sliding station located at the preset workpiece feeding and discharging position; the sliding station bearing the workpiece is controlled to slide to the middle section of the workbench; the welding robot is controlled to weld the workpiece; and in response to completion of welding of the workpiece, the sliding station bearing the welded workpiece is controlled to return to the preset workpiece feeding and discharging position. According to the implementation mode, welding operation is alternately conducted on the two sliding stations through the welding robot, and the welding efficiency is improved.

Description

TECHNICAL FIELD

[0001] Embodiments of the present disclosure relate to the technical field of intelligent welding, and in particular to a welding workstation for a battery tray for a vehicle. BACKGROUND

[0002] With the rapid development of the new energy vehicle industry, the safety requirement for power batteries as core components is increasingly stringent. The battery tray for a vehicle, as a direct bearing and protection structure for a power battery, needs to be able to withstand the weight of the battery module and the vibration impact during vehicle driving. At present, the battery tray is often welded manually.

[0003] However, in practice, it is found that when the above-mentioned way is used for tray welding work, the welding efficiency is often low due to the influence of the physical fluctuations of the operator.

[0004] The above information disclosed in this BACKGROUND section is only for the purpose of enhancing the understanding of the background of the present disclosure and, therefore, it can contain information that does not form the prior art that is already known in this country to those ordinary skilled in the art. SUMMARY

[0005] The summary of the present disclosure is intended to introduce the concepts in a simplified form, which will be described in detail in the following detailed description. The summary of the present disclosure is not intended to identify key or essential features of the claimed technology nor is it intended to be used to limit the scope of the claimed technology.

[0006] Some embodiments of the present disclosure propose a welding workstation for a battery tray for a vehicle to solve one or more of the technical problems mentioned in the above BACKGROUND section.

[0007] Some embodiments of the present disclosure provide a welding workstation for a battery tray for a vehicle, the welding workstation comprising a welding device, a carrying robot and a controller, wherein the welding device comprises a welding robot and a workbench, and the welding robot is located at the middle section of the workbench; each of the two sides of the workbench is provided with a sliding station; each sliding station is provided with a positioner; the carrying robot is provided with a sliding rail below; the controller is in communication connection with the welding device and the carrying robot; the controller is configured to perform the following steps: controlling the carrying robot to carry a workpiece to a sliding station located at a preset workpiece loading and unloading position; controlling the sliding station carrying the workpiece to slide to the middle section of the workbench; controlling the welding robot to weld the workpiece; in response to the completion of the welding of the workpiece, controlling the sliding station carrying the welded workpiece to return to the preset workpiece loading and unloading position.

[0008] Optionally, the welding station of the vehicle battery tray further comprises an upper and lower piece unit; both ends of the slide rail are respectively provided with one of the upper and lower piece units; the upper and lower piece unit comprises an upper piece table and a lower piece table.

[0009] Optionally, the upper piece table and the lower piece table are respectively provided with a position detection sensor; the position detection sensor is in communication connection with the controller.

[0010] Optionally, the carrying robot is provided with a carrying clamp; the positioner is provided with a work clamp.

[0011] Optionally, the welding station of the vehicle battery tray further comprises a fence; the fence is arranged on the periphery of the welding station of the vehicle battery tray.

[0012] Optionally, the fence is provided with a safety grating; the safety grating is in communication connection with the controller.

[0013] Optionally, the welding robot is an arc welding robot; the welding station of the vehicle battery tray further comprises a welding power supply, an automatic wire feeder and a welding torch.

[0014] Optionally, the workbench is provided with a guide rail; the sliding station is driven by a servo motor; the sliding station is configured to reciprocate along the guide rail.

[0015] Optionally, the carrying robot is a seven-axis robot.

[0016] Optionally, the positioner comprises a turnover driving assembly, a driven support assembly, a crossbeam and an arc blocking plate; the turnover driving assembly comprises a servo motor, a speed reducer, a slewing bearing and a brake device; the servo motor is connected to the input end of the speed reducer by a key; the output end of the speed reducer is connected to the slewing bearing; the brake device comprises a brake disc and a brake shoe; the brake shoe is arranged on both sides of the brake disc; the brake disc is connected to the output end of the speed reducer; the driven support assembly comprises a base and a sliding bearing; the sliding bearing is installed above the base; the turnover driving assembly and the driven support assembly are symmetrically connected to both ends of the crossbeam; the arc blocking plate is symmetrically arranged along both sides of the crossbeam, and the height of the arc blocking plate exceeds the end face of the crossbeam by a predetermined distance.

[0017] Some embodiments of the present disclosure provide a welding workstation for vehicle battery trays, which can improve the welding efficiency of vehicle battery trays. Specifically, the reason why the welding efficiency of most vehicle battery trays is low is that the battery trays are usually welded by manual operation, and the welding efficiency is usually affected by the physical fluctuations of the operators when the tray welding work is performed by manual operation. Based on this, some embodiments of the present disclosure provide a welding workstation for vehicle battery trays, which comprises a welding device, a carrying robot and a controller, wherein the welding device comprises a welding robot and a workbench, and the welding robot is located at the middle section of the workbench; each side of the workbench is provided with a sliding station; each sliding station is provided with a positioner; the carrying robot is provided with a sliding rail below; the controller is in communication connection with the welding device and the carrying robot; the controller is configured to perform the following steps: controlling the carrying robot to carry a workpiece to a sliding station located at a preset loading and unloading position; controlling the sliding station carrying the workpiece to slide to the middle section of the workbench; controlling the welding robot to weld the workpiece; and in response to the completion of the welding of the workpiece, controlling the sliding station carrying the welded workpiece to return to the preset loading and unloading position. On the one hand, the welding by the welding robot can avoid the influence of physical fluctuations in manual welding. On the other hand, one sliding station is provided at each end of the workbench, and the carrying robot can load and unload the workpiece to the other station when welding is performed on one of the stations. Thus, the welding efficiency of the vehicle battery tray is improved. BRIEF DESCRIPTION OF DRAWINGS

[0018] The above and other features, advantages, and aspects of embodiments of the present disclosure will become more apparent by describing in detail some embodiments thereof with reference to the attached drawings. The same or similar components have the same or similar reference numbers throughout the drawings. It should be understood that the drawings are schematic and elements and features are not necessarily to scale.

[0019] Figure 1 FIG. 1 is a structural schematic diagram of a welding workstation for vehicle battery trays according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0020] Embodiments of the present disclosure will be described more fully hereinafter with reference to the accompanying drawings. While several embodiments of the present disclosure are shown in the drawings, it is understood that the present disclosure can be embodied in various forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the present disclosure to those skilled in the art. It should be understood that the drawings and embodiments are for illustrative purposes only and are not intended to limit the scope of the present disclosure.

[0021] In addition, it needs to be noted that only parts related to the present application are shown in the drawings for the convenience of description. The embodiments in the present disclosure and the features in the embodiments can be combined with each other without conflict.

[0022] It should be noted that the concepts of “first”, “second” and the like mentioned in the present disclosure are only used to distinguish different devices, modules or units, and are not intended to limit the order or interdependence of the functions performed by these devices, modules or units.

[0023] It should be noted that the modification of “one”, “multiple” mentioned in the present disclosure is illustrative but not restrictive, and those skilled in the art should understand that unless otherwise explicitly indicated in the context, it should be understood as “one or more”.

[0024] The names of the messages or information exchanged between the plurality of devices in the embodiments of the present disclosure are only for illustrative purposes, and are not intended to limit the scope of the messages or information.

[0025] The present disclosure will be described in detail below with reference to the drawings and in conjunction with embodiments.

[0026] Figure 1 is a structural schematic diagram of a welding workstation of a battery tray for vehicles according to some embodiments of the present disclosure. Figure 1 It includes a welding robot 1, a workbench 2, a sliding station 3, a positioner 4, an upper piece table 5, a lower piece table 6, a carrying robot 7, and a sliding rail 8.

[0027] In some embodiments, the welding station of the battery tray for vehicle can include a welding device, a transfer robot 7 and a controller. The welding device can be used to realize the welding work of the battery tray. The transfer robot 7 can be responsible for the transfer of the workpiece. The controller can be the control core of the entire station, coordinating the work of each device. The controller can be an integrated device using PLC or industrial PC as the control core, matched with touch screen human-machine interface. The function of the controller is to coordinate and control the devices of the entire station, including the action sequence, speed and position of the devices. The welding device can include a welding robot 1 and a workbench 2, and the welding robot 1 can be located in the middle section of the workbench 2. The workbench 2 can be a cuboid frame structure welded by metal pipes, which can carry the workpiece to be welded. Each side of the workbench 2 can be provided with a sliding work station 3. The sliding work station 3 can be a metal plate with pulleys below. The pulleys can be driven to rotate by a driving mechanism (such as a motor), thereby driving the sliding work station 3 to slide. The motor can be installed on the side of the sliding work station 3, which is not limited here. The workbench 2 can be provided with a sliding groove. The sliding groove can be a strip-shaped groove opened on the surface of the workbench, which can roll the pulley and guide the pulley. When the sliding work station 3 on one side is loaded with a workpiece to be welded, it can be controlled by the controller to slide to the middle section of the workbench 2, and the welding robot 1 can perform welding work. At the same time, the sliding work station 3 on the other side can be loaded and unloaded by the transfer robot 7. The sliding work stations 3 on both sides can realize alternating feeding and welding, improving the work efficiency.

[0028] In some embodiments, each sliding work station 3 can be provided with a positioner 4. The positioner 4 can turn over the workpiece, so that the welding robot 1 can weld the workpiece at different angles to ensure the comprehensiveness of welding. The transfer robot 7 can be provided with a slide rail 8 below. The slide rail 8 can include a guide rail body, a sliding block and a ball. The guide rail body can be a long strip of steel (such as high-strength alloy structural steel), the surface of which is hardened and treated, and the cross section can be rectangular or square. The bottom is fixed on the ground or rack by bolts to provide a straight guide reference. The sliding block can be a steel block structure. The sliding block can be connected to the bottom of the transfer robot 7, and a ball or roller is embedded in the inside, which can slide along the guide rail body. The slide rail 8 can provide a straight moving path for the transfer robot 7, so that it can move back and forth between different work stations, expanding the work range. The controller can be in communication connection with the welding device and the transfer robot 7. The communication connection can be industrial Ethernet or field bus, which is not limited here.

[0029] In some embodiments, the controller can be configured to perform the following steps:

[0030] The first step is to control the transport robot to move the workpiece to a sliding station located at a preset loading / unloading position. This preset loading / unloading position can be the side of the worktable; there are no specific limitations, as long as loading and unloading can be performed normally. In practice, the controller can use sensors (such as infrared sensors) to detect whether the sliding station is at the preset loading / unloading position. Once the sliding station is detected to be at the preset loading / unloading position, the controller controls the transport robot to move the workpiece to be welded to the corresponding sliding station.

[0031] The second step is to control the sliding station carrying the workpiece to slide to the middle of the worktable. In practice, the controller described above can control the drive mechanism of the sliding station to make it slide to the middle of the worktable. A sensor (such as an infrared sensor) is used to detect whether the sliding station is in position.

[0032] The third step is to control the welding robot to weld the workpiece. In practice, the controller described above can control the welding robot to call a preset program to weld the workpiece. This preset program can be a program pre-programmed by the operator to control the welding robot to perform the welding.

[0033] The fourth step involves controlling the sliding station carrying the welded workpiece to return to the preset loading / unloading position in response to the completion of welding. In practice, the controller can control the sliding station carrying the welded workpiece to return to the preset loading / unloading position after receiving a signal from the welding robot indicating that the preset program has been completed. Sensors (such as infrared sensors) installed at the preset loading / unloading positions detect whether the sliding station is in position.

[0034] Optionally, such as Figure 1 As shown, the welding workstation for the aforementioned automotive battery tray may also include an unloading unit (composed of...). Figure 1 (Composed of an upper worktable 5 and a lower worktable 6). These upper and lower worktable units can serve as temporary storage and transfer areas for workpieces, facilitating loading and unloading by operators or external equipment. Each end of the slide rail 8 can have one of these upper and lower worktable units, corresponding to two sliding stations 3. Each upper and lower worktable unit can include an upper worktable 5 and a lower worktable 6. The upper worktable 5 can be used to place battery tray workpieces to be welded, and the lower worktable 6 can be used to place welded battery tray workpieces, achieving classified storage of workpieces and reducing confusion. Both the upper worktable 5 and the lower worktable 6 can be directional frames welded from metal tubes.

[0035] Optionally, the upper loading table 5 and the lower loading table 6 can be provided with a position detection sensor. The position detection sensor can be an optical sensor or a proximity switch, which can detect whether the workpiece is placed in position. The position detection sensor can be in communication with the controller. When the position detection sensor detects that the workpiece is in position or removed, a signal can be fed back to the controller, and the controller determines whether to start the pick-and-place action of the transfer robot 7, thereby reducing the misoperation caused by the workpiece not being in position.

[0036] Optionally, the transfer robot 7 can be provided with a transfer clamp. The transfer clamp can be a pneumatic clamp jaw adapted to the shape of the battery tray, which has a certain clamping force adjustment function and can grasp battery trays of different specifications. The positioner 4 can be provided with a work clamp. The work clamp can be a mechanical chuck, which is not limited here. The work clamp can fix the workpiece on the positioner 4, thereby reducing the displacement of the workpiece during welding and improving the welding size accuracy.

[0037] Optionally, the welding workstation for the automotive battery tray can further include a fence. The fence can be a combination structure of a metal frame and a protective net, and the height can be not less than 1.5 meters. The fence can be arranged on the periphery of the welding workstation for the automotive battery tray. The welding operation area can be separated from the external environment, thereby reducing the risk of non-operating personnel entering the welding area and causing harm to personnel, and reducing the interference of the external environment on the welding operation.

[0038] Optionally, the fence can be provided with a safety light barrier. The safety light barrier can be composed of a transmitter and a receiver, forming an invisible infrared light beam barrier. The safety light barrier can be in communication with the controller. When an object blocks the light beam, the safety light barrier can send a signal to the controller, and the controller can control all devices in the workstation to stop running until the danger is removed, thereby maximizing personnel safety.

[0039] Optionally, the welding robot 1 can be an arc welding robot. The arc welding robot can adopt a gas shielded arc welding or tungsten inert gas welding technology, which is suitable for welding of metal components such as battery trays, and has high weld strength and good forming. The welding workstation for the automotive battery tray can further include a welding power source, an automatic wire feeder, and a welding torch. The welding power source can provide current and voltage for welding. The automatic wire feeder can uniformly feed the welding wire to the welding torch, ensuring continuous supply of filler metal. The welding torch can serve as the terminal component for generating the welding arc and feeding the welding wire.

[0040] Optionally, the workbench 2 can be provided with guide rails. The guide rails can be linear guide rails. The surface of the guide rails can be hardened to increase wear resistance. The sliding stations 3 can be fixedly connected to the sliding blocks of the guide rails. The sliding stations 3 can be driven by servo motors. The servo motors can be connected to the transmission mechanisms of the guide rails through reducers to control the movement of the sliding stations 3. The transmission mechanisms can be ball screws, which are not limited here. The sliding stations 3 are configured to reciprocate along the guide rails. Through reciprocating sliding, the workpieces can be switched between the "welding standby positions (both sides of the workbench)" and the "welding positions (middle section of the workbench)", and continuous operation can be achieved in cooperation with the welding rhythm. The guide rails can be two, respectively corresponding to the two sliding stations 3 below, to realize the independent control of the two sliding stations 3.

[0041] Optionally, the carrying robot 7 can be a seven-axis robot. Compared with the traditional six-axis robot, the seven-axis robot has one more axis, higher flexibility, can realize more complex spatial motion trajectory, can adapt to the taking and placing requirements of the battery tray at different angles, and can improve the adaptability of workpiece transfer.

[0042] Optionally, the positioner 4 can include a turnover driving assembly, a driven support assembly, a crossbeam and an arc shielding plate. The turnover driving assembly can include a servo motor, a speed reducer, a slewing bearing and a brake device. The servo motor can provide turnover power, the speed reducer can reduce the rotation speed and increase the torque, the slewing bearing can realize smooth rotation, and the brake device can lock the position of the crossbeam after turnover to ensure the stability of the workpiece posture. The servo motor can be connected to the input end of the speed reducer through a key. The output end of the speed reducer can be connected with the slewing bearing, which can transmit power to the slewing bearing to drive the workpiece to turn over. The brake device can include a brake disc and a brake pad. The brake disc can be a metal disc with frosted surface. The brake pad can be a metal ceramic brake pad, which is made of metal powder as the matrix and mixed with ceramic particles (aluminum oxide, zirconium oxide). Compared with traditional metal brake pads and ceramic brake pads, the metal ceramic brake pad has higher friction coefficient, higher temperature resistance and stronger braking stability, and is suitable for scenes with large braking load such as vehicle battery tray. The brake pad can be arranged on both sides of the brake disc to achieve braking by clamping the brake disc. The brake disc can be connected with the output end of the speed reducer, which can rotate synchronously with the output end of the speed reducer to ensure the control accuracy of the turnover position. The driven support assembly can include a base and a sliding bearing. The base can be a square block structure. The sliding bearing can be installed above the base. The turnover driving assembly and the driven support assembly can be symmetrically connected to both ends of the crossbeam. Symmetrical connection can make the crossbeam bear force uniformly, reduce the shaking caused by the deviation of the center of gravity, and ensure the stability of the workpiece during turnover. The arc shielding plate can be symmetrically arranged along both sides of the crossbeam, and the height can exceed the end face of the crossbeam by a predetermined distance. The arc shielding plate can be a high-temperature-resistant metal plate, such as galvanized steel plate, which can block the arc light and spatter generated during welding to protect the surrounding equipment such as the sliding station 3 and the guide rail from damage, and reduce the irritation of arc light to the operator.

[0043] Further, in the mass production process of the vehicle battery tray, the weld quality directly determines the structural safety and service life of the product. As a core component for carrying battery modules, the vehicle battery tray needs to withstand complex loads such as battery weight and vehicle driving vibration for a long time. If there is a risk of cracking in the weld, it may cause serious safety problems such as battery loosening and electric leakage. In the welding process of the vehicle battery tray, the quality of the weld is affected by multiple links such as the sufficiency of preheating, the uniformity of cooling, and the control of residual stress. In the commonly used welding process, there are problems such as insufficient metal preheating before welding, resulting in insufficient welding wire filling, lack of real-time regulation during the cooling process causing stress concentration, and ineffective release of residual stress after welding. These problems are prone to cause defects such as incomplete fusion and micro-cracks in the weld, ultimately increasing the risk of weld cracking. In order to reduce the risk of weld cracking of the vehicle battery tray and improve the stability of the welding quality, some embodiments of the present disclosure provide the following solutions.

[0044] Optionally, the welding workstation of the vehicle battery tray described above can further include an infrared thermal imager. The infrared thermal imager described above can be a device that uses infrared thermal imaging technology to detect the infrared radiation of the target object, and through signal processing, photoelectric conversion and other means, converts the temperature distribution image of the target object into a visible image. The infrared thermal imager described above can be installed above the welding robot working area. Here, the installation position of the infrared thermal imager is not specifically limited, as long as the temperature change of the weld can be monitored. The welding equipment described above can further include a pulse laser, an ultrasonic assembly and a welding gun. The ultrasonic assembly described above can be a device that applies impact energy to the weld area through high-frequency mechanical vibration to release residual tensile stress, which is composed of an ultrasonic generator, a piezoelectric transducer, an amplitude transformer and a tool head. Among them, the tool head can be made of hard alloy material, which has high wear resistance. The tool head can be a long strip structure, and one end of it can be a spherical structure with a diameter of 3-8 mm, which is used to directly contact the weld to transmit vibration to the weld. The piezoelectric transducer, the amplitude transformer and the tool head can be integrated into an execution component and installed on the flange plate of the welding robot. The execution component can be connected to the ultrasonic generator through a cable. The welding gun can be installed on the flange of the welding robot. The pulse laser is installed on the welding gun, and the center of the laser of the pulse laser coincides with the welding point of the welding gun. Among them, installing the pulse laser on the welding gun can make the pulse laser move with the welding gun. Before the welding gun welds, a spoon hole is formed on the workpiece surface by the pulse laser, which can melt the metal in advance, so that the welding wire can be filled more easily, thereby improving the welding strength and depth. The controller described above can be in communication connection with the infrared thermal imager, the pulse laser and the ultrasonic assembly. The communication connection can be wired connection, for example, through field bus, which is not specifically limited here. The controller can be further configured to perform the following steps:

[0045] In the first step, the identification code of the workpiece is identified to obtain identification information. The identification code can be a bar code or a two-dimensional code attached to the surface of the workpiece in a non-welding area, which is not limited herein. The identification information can be a series of numbers representing the model to which the workpiece belongs. In practice, the controller can control the camera to identify the identification code of the workpiece to obtain the identification information.

[0046] In the second step, the corresponding welding parameter information is matched from the preset workpiece database according to the identification information. The preset workpiece database can include the mapping relationship between each identification information and each welding parameter information. The welding parameter information can include welding torch path, welding start point position coordinates, welding speed and other parameters. The welding torch path can be stored in the form of a set of coordinate points. In practice, the controller can use SQL (Structured Query Language) to query the welding parameter information matched with the identification information from the preset workpiece database.

[0047] In the third step, the welding robot is controlled to move the welding torch to the welding start point according to the welding parameter information. In practice, the controller can control the welding robot to move the welding torch to the position corresponding to the welding start point position coordinates included in the welding parameter information, which is the welding start point.

[0048] In the fourth step, the pulsed laser is controlled to emit laser to form a spoon hole at the welding position. The spoon hole refers to a small molten pool structure formed on the surface of the workpiece in advance by the pulsed laser before welding, and its core function is to create favorable conditions for subsequent welding wire filling and improve welding quality. In practice, the controller can send a trigger signal to the pulsed laser, and the pulsed laser emits a laser beam to melt the metal on the surface of the workpiece corresponding to the welding start point to form a spoon hole. For example, the controller can control the pulsed laser to emit laser at the welding start point for 30 ms to melt the surface of the aluminum alloy of the battery tray to form a spoon hole with a diameter of about 3 mm and a depth of about 2 mm, preparing for subsequent welding wire filling.

[0049] In the fifth step, the welding torch is controlled to weld the formed spoon hole. In practice, the controller can start the wire feeding mechanism and arc generator of the welding torch, and the welding wire is melted by the arc and filled into the spoon hole for welding, while the welding torch can move along the preset welding path to form a continuous weld. The preset welding path can be the welding torch path included in the welding parameter information.

[0050] In the sixth step, the cooling rate of the formed weld is determined by the infrared thermal imager in response to the formation of the first preset length of the weld. The length of the weld can be calculated by the controller based on the displacement of the welding torch along the welding torch path. In practice, the controller can trigger the infrared thermal imager to record the temperature of the weld at different time points when the length of the weld reaches the first preset length. For example, the first preset length is set to 50 mm, and the infrared thermal imager is triggered by the controller when the weld extends to 50 mm from the starting point. The infrared thermal imager measures the initial temperature of the weld to be 900°C, and the temperature decreases to 400°C after 10 seconds, and the cooling rate is calculated to be (900-400) / 10=50°C / s.

[0051] In the seventh step, the welding speed of the welding robot is adjusted in response to the cooling rate being higher than a preset threshold. In practice, the controller can compare the cooling rate calculated in the sixth step with the preset threshold, and if the cooling rate is higher, it indicates that the heat is lost too quickly during the welding process, and the welding speed needs to be reduced to reduce the rapid loss of heat. For example, the preset cooling rate threshold is set to 40°C / s, and if the cooling rate measured in the sixth step is 50°C / s, the controller sends a speed reduction instruction to the robot to reduce the welding speed by a preset size, prolongs the local heating time, and reduces the cooling rate. Here, the specific value of the preset threshold is not limited and can be adjusted according to actual needs.

[0052] In the eighth step, the formed weld is subjected to stress relief treatment by the ultrasonic assembly in response to the formation of the second preset length of the weld. The length of the weld can be obtained by the controller calculating the displacement of the welding torch in the welding torch path. The stress relief treatment can refer to a process operation of applying high-frequency mechanical vibration to the completed weld by the ultrasonic assembly to release the residual tensile stress inside the weld, with the purpose of improving the mechanical properties of the weld and reducing the risk of cracking. The principle is that during the welding process, the metal is quickly cooled after being melted at high temperature, and the weld and the surrounding area will produce residual tensile stress due to uneven thermal expansion and contraction. If the residual stress is too large, it may cause deformation, cracking and other defects in the weld in the later stage. The stress relief treatment applies continuous impact energy to the weld area by high-frequency vibration of the ultrasonic assembly, so that the metal internal lattice is rearranged, thereby relieving or eliminating the residual tensile stress. In practice, when the length of the weld reaches the second preset length, the controller can start the ultrasonic assembly to apply impact energy to the weld by high-frequency mechanical vibration to perform stress relief treatment on the formed weld. For example, the second preset length is set to 200 mm, and when the weld extends to 200 mm, the controller starts the ultrasonic assembly. The ultrasonic generator outputs a 20 kHz high-frequency signal, which is converted into mechanical vibration by a piezoelectric transducer, amplified by a variable amplitude rod, and then contacts the weld surface through a hard alloy spherical tool head with a vibration pressure of 100 N for 15 seconds to relieve the residual tensile stress generated during the cooling process of the weld.

[0053] The optional embodiment above solves the technical problem of "easy cracking of the weld of the battery tray for vehicle" as one of the inventive points of the embodiment of the present disclosure. The factors that cause the weld of the battery tray for vehicle to be easy to crack are as follows: first, the metal is not fully preheated before welding, the filling resistance of the welding wire is large, and unmelted defects are easy to occur, resulting in insufficient welding strength and depth; second, the cooling rate of the weld is not monitored and adjusted in real time, and internal stress concentration is easy to occur when the cooling is too fast, causing micro cracks; third, the residual tensile stress after welding is not effectively released, and the weld is easy to deform or crack due to stress accumulation during use of the workpiece. If the above factors are solved, the effect of making the weld of the battery tray for vehicle not easy to crack can be achieved. In order to achieve this effect, the present disclosure further provides a collaborative control welding scheme integrating a pulsed laser, an infrared thermal imager and an ultrasonic assembly. On the one hand, the pulsed laser is used to pre-form a spoon hole before welding to melt the metal in advance to reduce the filling resistance of the welding wire and effectively improve the welding strength and depth; on the other hand, the infrared thermal imager is used to monitor the cooling rate of the weld in real time, and the welding speed is dynamically adjusted to ensure the uniformity of cooling, and the ultrasonic assembly is used to release the stress of the weld to relieve the residual tensile stress. Thus, the effect of making the weld of the battery tray for vehicle not easy to crack is achieved.

[0054] Further, in the mass production process of the battery tray for vehicle, the welding quality is directly related to the structural strength and safety of the product, and the cleaning state of the nozzle of the welding gun as the core equipment of the welding operation has a key influence on the welding quality. In the welding process flow of the battery tray for vehicle, the nozzle of the welding gun is exposed to the high-temperature arc environment for a long time, and is easy to attach metal splashes. After chemical reaction between the splashes and the nozzle surface, hard metal compound impurities are formed. If these impurities are not effectively removed, the arc stability will be reduced, the welding wire feeding will be blocked, and then problems such as poor weld forming, insufficient strength and the like will be caused, and in severe cases, rework treatment is required, affecting the production efficiency. The commonly used cleaning method of the welding gun at present depends on mechanical scraping or low-pressure air blowing, and such method has limited cleaning effect on the metal compound impurities with strong adhesion, and is difficult to meet the cleaning requirements of high-precision welding.

[0055] Optionally, the welding station of the vehicle battery tray can further comprise a welding gun cleaning device. The device can be used for regular cleaning and maintenance of the welding gun, reducing the influence of nozzle blockage and splash residue on welding quality during welding, and ensuring the stability and continuity of welding operations. The welding gun cleaning device can include a housing, a dust collection box, a fan, a laser, and an industrial camera. The housing can be the main structure of the welding gun cleaning device, made of metal material, and has the function of dustproof and protection of internal components. The inside forms a closed space to ensure the centralized treatment of dust during cleaning. The shape of the housing can be a square structure, which is not limited here. The dust collection box, the fan, the laser, and the industrial camera can be arranged inside the housing, and the industrial camera can be equipped with a fill light. The dust collection box can adopt a drawer structure, which is convenient for later disassembly and cleaning of collected dust and debris. The fan can provide airflow power for the cleaning process, accelerating the collection and discharge of dust. The laser can be used to emit a laser beam to burn the splash and oxide residues on the surface of the welding gun by high temperature, realizing the cleaning function. The laser can be a pulse laser. The industrial camera can be used for real-time detection of the cleaning state of the welding gun, and the fill light can provide sufficient illumination when the light inside the housing is insufficient, ensuring clear camera images. The dust collection box can be arranged below the welding gun cleaning device. The splash, dust, and other impurities generated during the welding process can naturally fall or be guided by the airflow into the dust collection box during the cleaning process, achieving centralized collection and reducing the pollution of impurities scattered inside the device or the workstation environment. The fan can be arranged on the side wall of the welding gun cleaning device. The fan can generate directional airflow when working, blowing the smoke and fine dust generated during laser cleaning to the direction of the dust collection box, enhancing the dust collection effect, and also preventing dust from adhering to the surface of precise components such as lasers and industrial cameras, affecting their working performance. The welding gun cleaning device can be in communication with the controller. The controller can automatically trigger the welding gun cleaning device to start working according to the preset conditions such as the number of weldings and the welding time; the controller can also analyze the degree of welding gun contamination through images captured by the industrial camera, and when the detected welding gun surface impurity residue reaches a threshold value, the controller controls the cleaning device to start the laser, fan, and other components for cleaning operations. After cleaning, the industrial camera captures the welding gun image again and feeds back to the controller, which judges whether the cleaning effect meets the standard. If not, the control device repeats the cleaning process until the welding gun state meets the welding requirements. The controller can be further configured to perform the following steps:

[0056] In the first step, the welding robot is controlled to move the welding torch into the inside of the cleaning device in response to reaching a cleaning trigger condition. The cleaning trigger condition can be that the number of weld seams welded by the welding robot consecutively reaches a preset number. The specific value of the preset number is not limited. For example, the welding robot is automatically cleaned after welding 50 weld seams consecutively. In practice, the controller can send a moving instruction to the welding robot to make it carry the welding torch into the shell of the cleaning device when the cleaning trigger condition is met.

[0057] In the second step, the industrial camera is controlled to take a photo of the nozzle of the welding torch to obtain pre-cleaning image information. The pre-cleaning image information can be a photo taken of the nozzle of the welding torch before cleaning. In practice, the controller can trigger the industrial camera to work after detecting that the welding torch is in place, and the fill light is turned on at the same time to provide sufficient illumination. The camera takes multiple-angle photos of the nozzle of the welding torch to obtain images containing the state of the splashes and the residues of oxides, and the obtained images are determined as the pre-cleaning image information.

[0058] In the third step, the cleaning parameters are determined according to the pre-cleaning image information. In practice, the controller can use an edge detection algorithm to identify the positions of impurities and record the coordinates of the positions of the impurities. The coordinates of all the positions of the impurities are combined to form a coordinate set, and the formed coordinate set is determined as the cleaning parameters.

[0059] In the fourth step, the fan is started. In practice, the controller can send a starting signal to the fan, and the fan starts to generate a directional airflow. The direction of the airflow can be directed by the side wall to the dust collection box below to prepare for the collection of dust during the subsequent laser cleaning.

[0060] In the fifth step, the laser is controlled to move along a preset path. The laser emits laser light to the nozzle when the laser passes through a preset point. The preset path can be a preset path that enables the laser to scan the entire nozzle. For example, the preset path can be a spiral path around the nozzle. The preset point can correspond to the coordinate point set included in the cleaning parameters determined in the third step, so that the laser can accurately hit the corresponding coordinate point on the nozzle of the welding torch when the laser is emitted, and targeted cleaning is achieved.

[0061] In the sixth step, the industrial camera is controlled to take a photo of the nozzle in response to the laser moving to the end point of the preset path to obtain post-cleaning image information. The post-cleaning image information can be a photo of the nozzle after cleaning. In practice, the controller can trigger the industrial camera and the fill light to work again after the laser moves to the end point of the preset path, and take photos of the cleaned nozzle at the same angle as in the second step to obtain the post-cleaning image information.

[0062] In the seventh step, the fan is turned off in response to the post-cleaning image information indicating that the cleaning is qualified. In practice, the above-mentioned controller can use an image comparison algorithm based on OpenCV to compare the post-cleaning image with a preset qualified template image. If the similarity of the images reaches a preset value, it is determined that the cleaning is qualified, and a signal is sent to turn off the fan.

[0063] The above-mentioned optional embodiment, as one of the inventive points of the embodiments of the present disclosure, solves the technical problem of low cleaning rate of metal compound impurities formed on the surface of the welding torch nozzle during the welding process of the battery tray for vehicles. The factors that cause the low cleaning rate of metal compound impurities formed on the surface of the welding torch nozzle during the welding process of the battery tray for vehicles are as follows: the high-temperature arc during welding causes the metal spatter to chemically react with the surface of the nozzle, forming hard metal compounds. Such impurities have strong adhesion and are difficult to completely remove by traditional mechanical cleaning. If the above-mentioned factors are solved, the effect of improving the cleaning rate of metal compound impurities on the surface of the welding torch nozzle can be achieved. In order to achieve this effect, the present disclosure further provides a scheme for removing metal compound impurities by laser high-temperature burning. On the one hand, an industrial camera locates the position of the metal compound impurities by image recognition and generates coordinate parameters, improving the accuracy of the laser targeting the impurity area. On the other hand, a pulsed laser emits a high-energy laser beam, and cooperates with a fan to direct the airflow and timely remove the impurity residues, achieving the removal of hard metal compounds. In this way, the cleaning rate of metal compound impurities on the surface of the welding torch nozzle is improved.

[0064] Some embodiments of the present disclosure provide a welding workstation for vehicle battery trays, which can improve the welding efficiency of vehicle battery trays. Specifically, the reason why the welding efficiency of most vehicle battery trays is low is that the battery trays are usually welded by manual operation, and the welding efficiency is usually affected by the physical fluctuations of the operators when the tray welding work is performed by manual operation. Based on this, some embodiments of the present disclosure provide a welding workstation for vehicle battery trays, which includes a welding device, a carrying robot, and a controller. The welding device includes a welding robot and a workbench, and the welding robot is located at the middle section of the workbench. Each side of the workbench is provided with a sliding station, and each sliding station is provided with a positioner. The carrying robot is provided with a sliding rail below. The controller is in communication connection with the welding device and the carrying robot. The controller is configured to perform the following steps: controlling the carrying robot to carry a workpiece to a sliding station located at a preset loading and unloading position; controlling the sliding station carrying the workpiece to slide to the middle section of the workbench; controlling the welding robot to weld the workpiece; and in response to the completion of the welding of the workpiece, controlling the sliding station carrying the welded workpiece to return to the preset loading and unloading position. On the one hand, the welding by the welding robot can avoid the influence of physical fluctuations in manual welding. On the other hand, one sliding station is provided at each end of the workbench, and the carrying robot can load and unload the workpiece to the other station while welding is performed on one of the stations. Thus, the welding efficiency of the vehicle battery trays is improved.

[0065] The above description is merely some preferred embodiments of the present disclosure and a description of the principles of the technology used. Those skilled in the art should understand that the scope of the application involved in the embodiments of the present disclosure is not limited to the technical solutions formed by the specific combinations of the above technical features, and should also cover other technical solutions formed by any combinations of the above technical features or equivalent features without departing from the above inventive concept. For example, the above features can be replaced with the technical features disclosed in the embodiments of the present disclosure (but not limited to) having similar functions to form technical solutions.

Claims

1. A welding station for automotive battery trays, characterized in that, The welding station of the vehicle battery tray comprises a welding device, a carrying robot and a controller, wherein The welding device comprises a welding robot and a workbench, and the welding robot is located in the middle section of the workbench; Each side of the workbench is provided with a sliding station; Each sliding station is provided with a positioner; The carrying robot is provided with a slide rail below; The controller is in communication connection with the welding device and the carrying robot; The controller is configured to perform the following steps: Controlling the carrying robot to carry the workpiece to the sliding station located at the preset loading and unloading position; Controlling the sliding station carrying the workpiece to slide to the middle section of the workbench; Controlling the welding robot to weld the workpiece; In response to the completion of the welding of the workpiece, controlling the sliding station carrying the welded workpiece to return to the preset loading and unloading position.

2. The battery tray welding station for automotive vehicles of claim 1, wherein, The welding station of the vehicle battery tray further comprises a loading and unloading unit; Each end of the slide rail is provided with one loading and unloading unit; The loading and unloading unit comprises a loading table and an unloading table.

3. The battery tray welding station for automotive vehicles of claim 2, wherein, Each of the loading table and the unloading table is provided with a position detection sensor; The position detection sensor is in communication connection with the controller.

4. The battery tray welding station of claim 1, wherein, The carrying robot is provided with a carrying clamp; The positioner is provided with a work clamp.

5. The battery tray welding station of claim 1, wherein, The welding station of the vehicle battery tray further comprises a fence; The fence is arranged at the periphery of the welding station of the vehicle battery tray.

6. The battery tray welding station of claim 5, wherein, The fence is provided with a safety grating; The safety grating is in communication connection with the controller.

7. The battery tray welding station of claim 1, wherein, The welding robot is an arc welding robot; The welding station of the vehicle battery tray further comprises a welding power supply, an automatic wire feeder and a welding torch.

8. The battery tray welding station of claim 1, wherein, The workbench is provided with a guide rail; The sliding station is driven by a servo motor; The sliding station is configured to reciprocate along the guide rail.

9. The battery tray welding station of claim 1, wherein, The carrying robot is a seven-axis robot.

10. The battery tray welding station of claim 1, wherein, The positioner comprises a turnover driving assembly, a driven support assembly, a crossbeam and an arc blocking plate; The turnover driving assembly comprises a servo motor, a speed reducer, a slewing bearing and a brake device; The servo motor is connected to the input end of the speed reducer by a key; The output end of the speed reducer is connected to the slewing bearing; The brake device comprises a brake disc and a brake shoe; The brake shoe is arranged on both sides of the brake disc; The brake disc is connected to the output end of the speed reducer; The driven support assembly comprises a base and a sliding bearing; The sliding bearing is installed above the base; The turnover driving assembly and the driven support assembly are symmetrically connected to both ends of the crossbeam; The arc blocking plate is symmetrically arranged along both sides of the crossbeam, and the height of the arc blocking plate exceeds the end face of the crossbeam by a preset distance.

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