Intelligent laser welding equipment for part machining

Abstract

The application relates to the technical field of laser welding, and discloses an intelligent laser welding device for part machining, which comprises a base, a protective cover is arranged at the top of the rear end of the base, a moving seat is arranged at the top of the front end of the base, a moving platform is arranged at the top of the moving seat, and a control element is arranged on the left side of the base; four functional modules of safety monitoring, positioning feedback, intelligent control and maintenance management are integrated in the control element through a data bus, thereby forming a complete closed-loop control system from safety monitoring, position control, process adjustment to equipment maintenance. Data intercommunication and collaborative work are realized among the modules, and intelligent management of the whole process of equipment operation is realized. According to the technical scheme, the stability index of the equipment system reaches more than 99.5%, and the width of a laser welding heat-affected zone can be controlled in a very small range, so that the high-quality welding requirements of precise parts in the fields of automobile manufacturing, electronic components, medical devices and the like can be fully met.

Description

Technical Field

[0001] This invention relates to the field of laser welding technology, specifically to an intelligent laser welding device for parts processing. Background Technology

[0002] Laser welding technology, with its advantages of high energy density, small heat-affected zone, and high welding quality, has become a key process in the processing of precision parts in automobile manufacturing, electronic components, and medical devices. With the deepening development of intelligent manufacturing technology, industrial production is placing higher demands on the automation and intelligence levels of welding equipment. Especially in the mass production of complex structural parts and high-precision components, equipment needs to achieve precise positioning, real-time monitoring, and intelligent control to meet the dual needs of modern manufacturing for product quality and production efficiency.

[0003] However, existing laser welding equipment still suffers from insufficient stability in positioning accuracy during practical applications. Traditional laser welding equipment often employs a simple open-loop control structure for its moving platform, lacking a high-precision closed-loop feedback system. During continuous operation, the repeatability of the moving platform is easily affected by factors such as mechanical vibration and temperature drift, causing fluctuations that lead to deviations between the welding trajectory and the preset path. This is particularly problematic when welding small parts or irregularly shaped curved surfaces, making it difficult to guarantee the uniformity and consistency of the weld, directly impacting product yield and quality stability. Because positioning accuracy cannot be effectively guaranteed, the consistency of welding quality is difficult to maintain after prolonged operation, resulting in high rework and scrap rates, increasing production costs and time consumption. Furthermore, fluctuations in positioning accuracy limit the application of the equipment in high-precision scenarios, hindering the full realization of the technological advantages of laser welding in precision manufacturing fields with stringent welding accuracy requirements. Summary of the Invention

[0004] In order to solve the technical problems in the prior art, this application provides an intelligent laser welding equipment for parts processing.

[0005] This application provides an intelligent laser welding equipment for parts processing, employing the following technical solution: An intelligent laser welding equipment for parts processing includes a base, a protective cover mounted on the top of the rear end of the base, a movable seat mounted on the top of the front end of the base, a movable platform mounted on the top of the movable seat, a control component located on the left side of the base, an alarm mounted on the top of the left side of the protective cover, a tool holder located inside the left side of the protective cover, a first drive assembly mounted inside the protective cover, a second drive assembly mounted on the outer wall of the first drive assembly, and a laser welding machine mounted on the outer wall of the second drive assembly. The control component integrates a safety monitoring module, a positioning feedback module, an intelligent control module, and a maintenance management module. These four functional modules communicate with each other via a data bus, forming a complete closed-loop control system from safety monitoring to positioning feedback, then to intelligent control, and finally to maintenance management.

[0006] Preferably, the safety monitoring module includes a laser beam offset sensor, a radiation intensity sensor, an ambient temperature sensor, and a visual monitoring component; the laser beam offset sensor is magnetically mounted on the inner wall of the protective cover, with its probe facing the welding area; the radiation intensity sensor is arranged around the welding area via a threaded connection, with its probe facing the interior of the laser welding machine, and includes a high-speed camera and an illumination source.

[0007] Preferably, the safety monitoring module calculates the safety risk index of the welding area based on three key parameters: laser beam offset, radiation intensity, and ambient temperature, and outputs different warning signals to the alarm according to the differences in the safety risk index level.

[0008] Preferably, the positioning feedback module includes a high-precision position sensor and a closed-loop control unit; the high-precision position sensor is embedded in the bottom of the mobile platform and is designed using the principle of a grating ruler to collect the three-dimensional position coordinate data and rotation angle data of the mobile platform in real time; the closed-loop control unit has a built-in PID control algorithm, which calculates the position deviation value by receiving the actual position information fed back by the position sensor and comparing it with the preset target position, and generates a correction signal, which is then transmitted to the drivers of the first drive component and the second drive component.

[0009] Preferably, both the first drive assembly and the second drive assembly adopt a structure of servo motor plus ball screw. The servo motor is connected to the power input end of the ball screw through a coupling, and the screw nut of the ball screw is fixedly connected to the driven object. The first drive assembly and the second drive assembly are connected through a coupling to form a multi-axis linkage system, which is uniformly coordinated and controlled by a control component.

[0010] Preferably, the intelligent control module includes a material property identification unit and a parameter optimization unit; the material property identification unit is equipped with a spectral analysis device to determine the material type and thickness information of the workpiece by identifying the reflectance spectral characteristics of the workpiece surface; the parameter optimization unit has a built-in welding process parameter library for different materials, and automatically adjusts the laser power and focusing position according to the material properties and environmental parameters.

[0011] Preferably, the parameter optimization unit can calculate the thermal deformation compensation amount in real time based on the temperature change data of the welding area, and superimpose the compensation amount onto the target position of the positioning feedback module to realize dynamic compensation of thermal deformation during the welding process.

[0012] Preferably, the maintenance management module includes a tool condition monitoring unit and an automatic cleaning unit; the tool condition monitoring unit collects wear area and wear depth data of the welding head through a wear sensor installed near the laser welding head, and calculates the remaining tool life; the automatic cleaning unit is equipped with a contamination level monitoring sensor and a cleaning actuator, and adjusts the cleaning frequency according to the contamination level of the optical component surface.

[0013] Preferably, the alarm is equipped with a warning light and a buzzer, the warning light including a yellow light source and a red light source; the alarm has three warning levels: in the low-risk state, the yellow warning light is continuously lit; in the medium-risk state, the yellow warning light is lit and accompanied by intermittent buzzing; in the high-risk state, the red warning light is lit and accompanied by continuous buzzing, while simultaneously sending a cut-off signal to the control unit.

[0014] Preferably, the tool holder adopts a modular design, the overall frame is made of aluminum alloy, and it is equipped with multiple standardized tool storage positions, each equipped with an electromagnetic induction position sensor; the control component can determine whether a tool is stored in the storage position and the type of tool stored based on the signal from the position sensor, and work with the drive component to realize automatic identification and rapid replacement of the welding head.

[0015] In summary, this application includes at least one of the following beneficial technical effects:

[0016] 1. This invention solves the problem of untimely and inaccurate identification of safety hazards caused by existing equipment relying solely on physical isolation and single-parameter alarms. By integrating a laser beam offset sensor, radiation intensity sensor, ambient temperature sensor, and high-speed visual monitoring components inside the protective cover, it achieves comprehensive real-time monitoring of the welding area. Based on multi-parameter fusion calculation of the safety risk index, a three-level early warning mechanism is established: low-risk prompts for attention, medium-risk prompts for enhanced warnings, and high-risk prompts for automatic laser output cutoff and shutdown. This technical solution can respond quickly to dangerous situations such as abnormal laser beam offset and excessive radiation, effectively preventing laser radiation from harming operators and significantly improving the inherent safety level of equipment operation.

[0017] 2. This invention overcomes the shortcomings of traditional open-loop control mobile platforms, which suffer from positioning accuracy fluctuations due to mechanical vibration and temperature drift. A high-precision position sensor based on the principle of an optical grating ruler collects real-time three-dimensional position and rotation angle data of the mobile platform. Combined with a closed-loop control unit with a built-in PID control algorithm, it can quickly calculate position deviations and generate correction signals to drive the dual servo ball screw assembly for dynamic adjustment. Simultaneously, through the multi-axis linkage design of the first and second drive components, it achieves a combination of coarse and fine positioning. This technical solution controls the total positioning error of the equipment to within 0.01mm, ensuring that the welding trajectory is highly consistent with the preset path. It effectively solves the problems of uneven weld seams and poor consistency when welding small parts and irregular curved surfaces, significantly improving the product qualification rate.

[0018] 3. This invention overcomes the limitations of existing equipment that relies on preset programs and cannot automatically adjust according to working conditions. It automatically identifies the material type and thickness information of the workpiece through a spectral analysis device, retrieves matching reference parameters from a built-in welding process parameter library, and makes corrections based on real-time ambient temperature. Simultaneously, it calculates the thermal deformation compensation amount based on temperature changes in the welding area and superimposes it onto the positioning system to achieve dynamic compensation. This technical solution eliminates the need for frequent manual adjustments of process parameters by operators, automatically adapts to the welding needs of various materials such as stainless steel, aluminum alloy, and titanium alloy, and workpieces of different thicknesses, reduces manual intervention, effectively reduces dimensional errors caused by thermal deformation, and further improves welding quality and production efficiency.

[0019] 4. This invention solves the problems of low efficiency in manual tool changing and untimely cleaning of optical components in existing equipment. The modularly designed tool holder is equipped with an electromagnetic induction position sensor, which can automatically identify the welding head type and, in conjunction with the drive assembly, complete rapid tool changing, achieving a tool changing efficiency of over 180 times per hour. A wear sensor monitors the wear area and depth of the welding head in real time, accurately predicting the remaining tool life and issuing early replacement reminders. The automatic cleaning unit dynamically adjusts the cleaning frequency based on the degree of surface contamination of the optical components, eliminating the need for periodic downtime for manual cleaning. This technical solution significantly shortens equipment maintenance and tool changing time, reduces unplanned downtime, and improves the continuous working capacity and production cycle of the equipment.

[0020] 5. This invention integrates four functional modules—safety monitoring, positioning feedback, intelligent control, and maintenance management—within the control unit via a data bus, forming a complete closed-loop control system encompassing safety monitoring, position control, process adjustment, and equipment maintenance. Data exchange and collaborative operation between modules enable intelligent management of the entire equipment operation process. This technical solution achieves a system stability rate exceeding 99.5%, while simultaneously controlling the width of the laser welding heat-affected zone to an extremely small range, fully meeting the high-quality welding requirements for precision components in fields such as automotive manufacturing, electronic components, and medical devices. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0022] Figure 2 This is a schematic diagram of the structure of the control component of the present invention;

[0023] Figure 3 This is a schematic diagram of the tool holder structure of the present invention;

[0024] Figure 4 This is a system schematic diagram of the control component of the present invention;

[0025] Figure 5 This is a flowchart illustrating the overall workflow of the present invention.

[0026] Explanation of reference numerals in the attached drawings: 1. Protective cover; 2. Base; 3. Alarm; 4. Control unit; 5. Movable seat; 6. Movable platform; 7. Tool holder; 8. First drive assembly; 9. Second drive assembly; 10. Laser welding machine. Detailed Implementation

[0027] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. In addition, the forms of the various structures described in the following embodiments are merely illustrative. The intelligent laser welding equipment for parts processing involved in the present invention is not limited to the structures described in the following embodiments. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] Please see Figures 1-5 The intelligent laser welding equipment for parts processing shown includes a base 2, a protective cover 1 installed at the top rear end of the base 2, a movable seat 5 installed at the top front end of the base 2, a movable platform 6 installed at the top of the movable seat 5, a control component 4 arranged on the left side of the base 2, an alarm 3 installed at the top left side of the protective cover 1, a tool holder 7 arranged inside the left side of the protective cover 1, a first drive assembly 8 installed inside the protective cover 1, a second drive assembly 9 installed on the outer wall of the first drive assembly 8, and a laser welding machine 10 installed on the outer wall of the second drive assembly 9.

[0029] The protective cover 1 is bolted to the top rear end of the base 2. The protective cover 1 has a fully enclosed structure, covering the entire welding work area (including the entire range of motion of the moving seat 5 and the moving platform 6). A sliding safety door is provided on the front of the protective cover. The safety door is equipped with an electromagnetic interlock device. When the safety door is opened, the laser welding machine 10 automatically cuts off the laser output. The inner wall of the protective cover is covered with laser absorbing material, which meets the requirements of Class 1 laser products in the GB7247.1-2012 laser product safety standard. The moving seat 5 is connected to the top front end of the base 2 via a slide rail. The moving platform 6 is mounted on the top of the moving seat 5 via a linear guide rail. A control component 4 is fixed to the left side of the base 2 via a bracket. An alarm 3 is installed on the top left side of the protective cover 1 via a buckle. A tool holder 7 is provided inside the left side of the protective cover 1 via a slide rail. A first drive assembly 8 is mounted inside the protective cover 1 via a bracket. A second drive assembly 9 is mounted on the outer wall of the first drive assembly 8 via a coupling. The laser welding machine 10 is mounted on the outer wall of the second drive assembly 9 via a flange.

[0030] In this embodiment, it should be specifically noted that the connection process between the base 2 and the protective cover 1, the movable seat 5 and the movable platform 6, and the first drive component 8 and the second drive component 9 is all rigidly connected using high-strength bolts. The base 2, the protective cover 1, the movable seat 5, and the movable platform 6 are all existing structures. The drive process of the first drive component 8 and the second drive component 9 can be achieved by a conventional servo drive structure. This embodiment does not impose specific limitations on them. The connection strength setting can be matched to the vibration load in the welding process of this embodiment.

[0031] It should be further explained that the first drive component 8 is a Z-axis drive component, responsible for driving the laser welding machine 10 to move along the vertical direction (Z-axis) to adjust the focusing position; the second drive component 9 is an XY-axis drive component, installed on the slide of the first drive component 8, responsible for driving the laser welding machine 10 to move along the horizontal direction (X-axis and Y-axis) to control the welding trajectory; both the first drive component 8 and the second drive component 9 are equipped with control components 4 on their exteriors. The control components 4 are used for data acquisition and central control of the operation of the laser welding machine 10. The control of the protective cover 1 adopts an independent control terminal. The independent control terminal is a conventional setting and is not specifically limited in this embodiment.

[0032] Control unit 4 serves as the central control hub of the entire equipment. Internally, it houses a central processing unit, memory, signal acquisition module, signal output module, and communication interface module. The display screen on control unit 4 shows real-time information such as equipment operating status, welding parameters, and alarm messages. Operators can input welding programs, adjust process parameters, and control equipment start and stop via the control unit 4's operation panel. Control unit 4 integrates four functional modules: a safety monitoring module, a positioning feedback module, an intelligent control module, and a maintenance management module. These four modules communicate with each other via a data bus. The output of the safety monitoring module is electrically connected to the input of the positioning feedback module, the output of the positioning feedback module is electrically connected to the input of the intelligent control module, and the output of the intelligent control module is electrically connected to the input of the maintenance management module, forming a complete closed-loop control system from safety monitoring to positioning feedback, then to intelligent control, and finally to maintenance management.

[0033] The safety monitoring module includes a laser beam offset sensor, a radiation intensity sensor, an ambient temperature sensor, and a visual monitoring component. The laser beam offset sensor is bolted to a dedicated mounting base on the inner wall of the protective cover 1. The mounting base has positioning pin holes to ensure the repeatability and stability of the sensor's installation position. The probe of the laser beam offset sensor faces the welding area, and its monitoring range covers the entire welding work area. When the laser beam deviates from the preset welding path, the laser beam offset sensor detects the offset and transmits the signal to the control component 4 for data processing. The radiation intensity sensor is arranged around the welding area via a threaded connection. The probe of the radiation intensity sensor faces the laser emission direction of the laser welding machine 10. The radiation intensity sensor is used to detect the laser radiation energy density in the work area. The threaded connection ensures that the sensor is securely installed and has good sealing performance. The working range of the radiation intensity sensor is selected according to the power level of the laser welding machine 10.

[0034] An ambient temperature sensor is fixed to the area surrounding the welding point via a high-temperature resistant ceramic bracket capable of withstanding temperatures above 500℃. The sensor probe is in close contact with the metal substrate of the welding area via high-temperature resistant thermally conductive silicone grease. The ambient temperature sensor monitors the temperature field distribution in the welding area; the addition of thermally conductive silicone grease improves temperature transfer efficiency and makes the measurement results more accurate. A visual monitoring component is fixedly mounted inside the protective cover 1 via a bracket. The visual monitoring component includes a high-speed camera and an illumination source. The high-speed camera operates at a frame rate of no less than 1000 frames per second to ensure clear capture of the dynamic process of laser welding. The illumination source provides sufficient lighting for the camera. The visual monitoring component is connected to the control unit 4 via a data cable to transmit image information of the welding process in real time. Operators can observe the welding area in real time through the display screen of the control unit 4.

[0035] In this embodiment, it should be specifically noted that the monitoring range of the laser beam offset sensor is 0.1-5.0 mm, and the detection range of the radiation intensity sensor is 0.5-10.0 W / cm².

[0036] The safety monitoring module calculates the safety risk index of the welding area based on multi-parameter normalized fusion. The calculation process includes the following steps: First, setting the safety threshold and danger threshold for each parameter: laser beam offset safety threshold. Danger threshold Radiation intensity safety threshold =0.5W / cm², danger threshold =5.0W / cm²; Ambient temperature safety threshold =45℃, danger threshold =80℃; The second step is to perform linear normalization on each parameter to obtain the dimensionless risk contribution value:

[0037] When the actual value is less than or equal to the safety threshold, the risk contribution value is... ;

[0038] When the safety threshold < the actual value < the danger threshold ;

[0039] When the actual value is greater than or equal to the danger threshold The third step is to calculate the comprehensive safety risk index based on the normalized risk contribution value. The formula for calculating the safety risk index S is: in The safety risk index (dimensionless, value range 0-1). The normalized risk contribution value for laser beam offset. The normalized risk contribution value for radiation intensity. The normalized risk contribution value for ambient temperature is given, where w1, w2, and w3 are the weights of each parameter's influence on safety risk, and w1 + w2 + w3 = 1. In this embodiment, w1 = 0.5, w2 = 0.3, and w3 = 0.2 (optimized based on actual application scenarios and historical data). The safety monitoring module establishes a multi-parameter normalized fusion safety risk index calculation model, eliminating the influence of differences in dimensions and significant variations in numerical ranges, thus achieving a comprehensive and accurate assessment of the safety status of the welding area.

[0040] The positioning feedback module includes a high-precision position sensor and a closed-loop control unit. The high-precision position sensor is embedded in the bottom of the moving platform 6. Designed using the principle of a grating ruler, the sensor consists of a reading head and a scale. The scale is fixed to the bottom of the moving platform 6, and the reading head is fixed to a corresponding position on the moving base 5. When the moving platform 6 moves, the reading head reads the position information on the scale. The high-precision position sensor has a resolution of no less than 0.001 mm, achieving an accuracy level of micrometers. It collects the three-dimensional position coordinates and rotation angle data of the moving platform 6 in real time and transmits this data to the closed-loop control unit. The closed-loop control unit incorporates a PID control algorithm. It receives the actual position information from the position sensor and compares it with a preset target position to calculate the position deviation. Based on the position deviation, it generates a correction signal according to preset PID parameters. This correction signal is transmitted via signal cables to the drivers of the first drive assembly 8 and the second drive assembly 9. The drivers adjust the speed and direction of the drive motors according to the correction signal, gradually bringing the actual position of the moving platform 6 closer to the target position.

[0041] The closed-loop control unit constructs a feedback control equation based on the position deviation. The calculation formula for the feedback control equation is as follows:

[0042] ;

[0043] in To control the output, This is the proportional gain coefficient (in this embodiment, the value is 200-400). This is the integral gain coefficient (in this embodiment, the value is 20-40). This is the differential gain coefficient (valued between 2 and 8 in this embodiment). Proportional gain. Ensure rapid system response, integral gain Eliminating steady-state error, differential gain Suppressing overshoot oscillation. Combining the 0.001mm resolution of the grating ruler and the ≤10ms response time of the servo motor, the steady-state error of the system can be controlled within 0.005mm through the above PID parameter tuning; coupled with the mechanical precision of the C3-grade ball screw (lead error ≤0.003mm / 300mm), the total positioning error δ of the moving platform is ≤0.01mm. The formula for calculating the positioning error is:

[0044] ;

[0045] in These represent the positioning errors for the X, Y, and Z axes, respectively, in millimeters. The rotational positioning error is expressed in millimeters (derived from the angular error multiplied by the rotation radius). A high-precision position sensor and a closed-loop control unit work together to form a closed-loop control system. This system collects real-time position data of the moving platform and compares it with a preset position. Based on the deviation value, a correction signal is generated and fed back to the drive components, achieving precise position correction. This effectively controls the three-axis positioning error and rotational positioning error of the moving platform, achieving sub-millimeter-level high-precision positioning and ensuring high-precision consistency between the welding trajectory and the preset path.

[0046] Both the first drive assembly 8 and the second drive assembly 9 adopt a servo motor plus ball screw structure. The servo motor is connected to the power input end of the ball screw through a coupling. The ball screw nut is fixedly connected to the driven object. When the servo motor rotates, the rotational motion is converted into linear motion through the ball screw. The lead accuracy of the ball screw reaches C3 level. The first drive assembly 8 and the second drive assembly 9 together constitute a three-axis linkage system, which is uniformly coordinated and controlled by the control component 4 to ensure the synchronization of their movements. A laser welding machine 10 is mounted on the outer wall of the second drive assembly 9 through a flange. The flange is provided with a positioning stop to ensure the installation accuracy of the laser welding machine 10. The laser generated by the laser generator of the laser welding machine 10 is transmitted to the laser welding head through an optical fiber. The laser beam emitted by the laser welding head irradiates the surface of the workpiece, melting the material and achieving welding.

[0047] The intelligent control module includes a material property identification unit and a parameter optimization unit. The material property identification unit is equipped with a spectral analysis device and a low-pressure plasma surface pretreatment unit. Before material identification, the pretreatment unit performs a 1-2 second plasma cleaning on the workpiece surface to remove surface oil, oxide layers, and dust. The spectral analysis device includes a spectral sensor and a light source. The light reflected from the pretreated workpiece surface is received by the spectral sensor, which converts the light signal into an electrical signal and transmits it to the control unit 4 for processing. The control unit 4 has a built-in database of spectral characteristics of commonly used metal materials and a surface state compensation algorithm. By analyzing the baseline drift and characteristic peak intensity ratio of the spectrum, it corrects the influence of surface roughness on the identification results, achieving a material identification accuracy of ≥99.5%. Spectral analysis technology identifies materials by recognizing the reflectance spectral characteristics of the workpiece surface. Different materials have different reflectance to different wavelengths of light. By analyzing the peak position and intensity distribution of the reflectance spectrum, the workpiece material can be accurately determined. The working wavelength range of the spectral analysis device covers the visible light to near-infrared region and is suitable for identifying various metal materials such as stainless steel, aluminum alloy, titanium alloy, and copper alloy.

[0048] The parameter optimization unit automatically adjusts the laser power and focusing position based on material properties and environmental parameters. The unit has a built-in library of welding process parameters for different materials. Once the material property identification unit identifies the workpiece material and thickness, the parameter optimization unit retrieves the corresponding baseline parameters from the library and performs correction calculations based on the real-time monitored ambient temperature. The corrected parameters are then transmitted as initial settings to the controller of the laser welding machine 10. The parameter optimization unit constructs a laser power optimization model based on the workpiece material and thickness. The calculation formula for the laser power optimization model is:

[0049] ;

[0050] in The optimal laser power is expressed in watts (W). The thickness of the workpiece is expressed in meters (m). The thermal conductivity of the material is expressed in watts per meter Kelvin (W / (m·K)). This is the difference between the material's melting point and the ambient temperature, expressed in Kelvin (K). The coefficients are dimensionless empirical coefficients (calibrated experimentally; 0.8-1.2 for aluminum alloys and 1.0-1.5 for stainless steel). This model comprehensively considers the effects of workpiece thickness, material thermal conductivity, and the temperature difference required for melting. Dimensional analysis is as follows: It is consistent with the unit of power and has a clear physical meaning.

[0051] There is a dynamic balance between laser power and welding speed. Excessive laser power can lead to over-melting or even burn-through of the material, while insufficient laser power will prevent the formation of an effective weld. The parameter optimization unit calculates the optimal power value based on the laser power optimization model, while also referencing the welding energy density formula. (in For welding energy density, For laser power, The welding speed is comprehensively optimized to ensure that the welding energy density meets the requirements for material melting. Thermal deformation compensation is a crucial step in the welding process. An infrared temperature sensor is specifically installed in the welding area (near the laser's point of application). This sensor has a temperature range of 0-500℃, a response time ≤1ms, and a sampling frequency of 100Hz, acquiring the instantaneous temperature T(t) of the welding area in real time. The thermal deformation compensation is calculated using a discrete integral form to adapt to dynamic temperature changes over time.

[0052] ;

[0053] in for The amount of thermal deformation compensation at any given time, in millimeters (mm). The coefficient of linear expansion of the material is expressed in Kelvin. ; The original length of the workpiece is in millimeters (mm). ( (Initial ambient temperature), in Kelvin (K); The sampling interval is 0.01s in this embodiment, and the unit is seconds (s). The thermal time constant (calibrated experimentally and related to workpiece material and size) is expressed in seconds (s). The parameter optimization unit superimposes the calculated compensation amount onto the target position of the positioning feedback module. The total response time of the thermal deformation compensation system is ≤5ms, synchronized with the 1kHz sampling frequency of the positioning feedback module, to achieve real-time dynamic compensation for thermal deformation.

[0054] The maintenance and management module includes a tool condition monitoring unit and an automatic cleaning unit. The tool condition monitoring unit monitors the wear level of the welding head in real time, using a non-contact laser displacement sensor mounted above the tool holder 7. Wear detection is performed when the welding head is replaced or the equipment is in standby mode. The laser displacement sensor has a resolution of 0.001 mm and a measurement range of 0-10 mm. By scanning the three-dimensional contour of the welding head end face, it calculates the wear area A and the maximum wear depth D. The tool condition monitoring unit calculates the remaining tool life based on the wear area and depth. The calculation formula for the remaining tool life is as follows:

[0055] ;

[0056] in Remaining lifespan, in hours (h); The initial lifespan is calibrated to 5000 hours. The wear area is expressed in square millimeters (mm²). The wear depth is expressed in millimeters (mm). The area influence coefficient is expressed in hours per square millimeter (h / mm²), with an experimental calibration value of 200h / mm². The value represents the depth influence coefficient, expressed in hours per millimeter (h / mm), with an experimental calibration value of 1500 h / mm. This linear model is applicable to the normal wear stage of the welding head (wear depth ≤ 0.3 mm). When the wear depth exceeds 0.3 mm, the remaining lifespan needs to be calculated using a nonlinear correction model. When the remaining lifespan falls below a preset threshold (500 hours), control component 4 issues a replacement reminder, facilitating advance planning of replacement schedules and reducing unplanned downtime.

[0057] The automatic cleaning unit periodically cleans the optical components. The unit is equipped with a contamination level monitoring sensor and a composite cleaning actuator. The contamination level monitoring sensor, installed near the optical components, monitors the surface contamination level in real time. It utilizes the principle of light intensity attenuation; when dust or splatter adheres to the optical component surface, the laser transmittance decreases, and the sensor detects this attenuation and converts it into a contamination level value. The composite cleaning actuator includes an air pressure nozzle and a rotating wiping head. The air pressure nozzle first sprays clean, dry compressed air at 0.3 MPa to remove loose dust particles from the surface. Then, the rotating wiping head (wrapped in a microfiber lint-free cloth) moves in a circular motion along the optical component surface at 50 rpm to remove firmly attached metal splatters and oil stains. The automatic cleaning unit adjusts the cleaning frequency based on the surface contamination level of the optical components. The calculation formula for the automatic cleaning frequency adjustment model is as follows:

[0058] ;

[0059] in Cleaning frequency is measured in times per hour (times / h). The pollution level value (dimensionless, ranging from 0 to 1). The reference frequency is set to 1 time per hour; To adjust the coefficient, the experimental calibration value was 2.0. The automatic cleaning unit calculates the degree of contamination based on data collected by the surface contamination sensor of the optical components. The more severe the contamination, the higher the cleaning frequency. By dynamically adjusting the cleaning frequency, the cleanliness of the optical components is ensured while avoiding resource waste and wear caused by over-cleaning.

[0060] Alarm 3 is electrically connected to the output of the security monitoring module. Alarm 3 outputs different warning signals based on the varying levels of the security risk index. Alarm 3 is equipped with warning lights and a buzzer. The warning lights include yellow and red light sources, which can be independently controlled to illuminate or extinguish. The buzzer produces beeping sounds of different frequencies and rhythms. Alarm 3 has three warning levels: Level 1 is a low-risk state, where the security risk index... The first level is determined to be a low-risk state, and the alarm 3 will illuminate a continuously lit yellow warning light to alert the operator to the equipment's operating status without affecting the normal welding process; the second level is a medium-risk state, when... The system is classified as medium risk. Alarm 3 illuminates a yellow warning light and sounds intermittently, twice per second for 0.2 seconds each time, enhancing the warning effect through sound to remind operators to closely monitor the equipment status. The third level is high risk. When the situation is determined to be high-risk, the alarm 3 illuminates a red warning light and sounds a continuous buzzer, while simultaneously sending a cut-off signal to the control unit 4. Upon receiving the cut-off signal, the control unit 4 immediately shuts down the laser output of the laser welding machine 10, forming a complete safety protection system.

[0061] The tool holder 7 is mounted on the left side of the protective cover 1 via a slide rail. The tool holder 7 adopts a modular design, with its overall frame made of aluminum alloy to reduce weight. It features multiple standardized tool storage slots, each with uniform dimensions to accommodate various welding head specifications. Each slot is equipped with a position sensor based on electromagnetic induction. When a welding head is placed in the slot, a metal marker inside the welding head triggers the sensor, generating a response signal. The position sensor transmits the detected welding head presence and type signal to the control unit 4. The control unit 4 determines whether a tool is stored in the slot and the type of tool stored there. Combined with the tool management function of the control unit 4, this enables automatic tool type identification and rapid tool replacement. When the operator changes the welding head, the control unit 4 sends a command to drive the moving seat 5 to move to the tool changing position above the tool holder 7. The second drive assembly 9 moves the laser welding machine 10 directly above the tool holder 7. After the welding head clamping mechanism of the laser welding machine 10 releases the old welding head, it moves directly above the storage position of the new welding head. The new welding head is picked up by the clamping mechanism and installed on the laser welding machine 10 to complete the tool changing action. The tool changing efficiency E ≥ 180 times per hour. The formula for calculating the tool changing efficiency is:

[0062] ;

[0063] in Tool changing efficiency is expressed in times per hour (times / h). This refers to the number of tool changes. Total tool change time, in hours (h).

[0064] In practical applications, the intelligent laser welding equipment of this invention is suitable for welding parts in the automotive manufacturing field. Taking the oil passage sealing welding of an automotive engine cylinder block as an example, the cylinder block workpiece to be welded is first placed in a fixture above the moving platform 6. The vacuum suction cup system is activated to fix the cylinder block. The moving seat 5 moves on the slide rail to the laser emission range of the laser welding machine 10. The position of the moving platform 6 is adjusted so that the oil passage sealing part to be welded is directly below the laser welding machine 10. The control unit 4 issues a pre-processing command, and the low-pressure plasma cleaning device is activated to clean the surface of the welding area for 1.5 seconds to remove oil and oxide layers. Subsequently, the spectral analysis device of the material characteristic identification unit is activated to identify the cylinder block material. The identification result shows that the cylinder block material is aluminum alloy 6061 with a thickness of 3 mm. The parameter optimization unit retrieves the corresponding welding parameters from the process parameter library based on the material information and performs optimization calculations, calculating the optimal laser power as 1800 watts and the optimal welding speed as 800 mm per minute.

[0065] Laser welding machine 10 starts emitting a laser beam. During the welding process, the visual monitoring component collects real-time image information of the welding area and transmits it to the control unit 4 for display. The operator can observe the formation process of the weld pool and the quality of the weld through the display screen. The safety monitoring module continuously monitors the laser beam offset, radiation intensity, and ambient temperature in the welding area. When the laser beam offset is maintained below 0.2 mm, the radiation intensity is maintained below 0.5 W / cm², and the ambient temperature is maintained below 45 degrees Celsius, the normalized risk contribution value of each parameter is 0, the safety risk index S=0, and the alarm 3 illuminates a yellow warning light continuously to indicate that the equipment is operating normally. When a sudden increase in laser beam offset to 0.8 mm is detected, the normalized risk contribution value of the laser beam offset... Other parameters have a risk contribution value of 0, and the safety risk index is... If the risk level reaches medium, alarm 3 will switch to a yellow warning light and intermittent buzzer mode to alert the operator. When the laser beam offset continues to increase beyond 1.2 mm, Safety risk index If the risk level is reached, the alarm 3 will immediately switch to a red warning light and continuous buzzing mode, and at the same time send a cut-off signal to the control unit 4. The control unit 4 will immediately shut down the laser output of the laser welding machine 10 and stop the drive motor of the moving seat 5. The equipment can only be restarted after the fault is cleared.

[0066] During continuous welding operations, the positioning feedback module monitors the position deviation of the moving platform 6 in real time using a high-precision position sensor. Assuming that mechanical vibration causes a 0.005 mm position deviation in the Y-axis direction during welding, the closed-loop control unit detects this deviation, immediately calculates the correction amount, and outputs a correction signal. The drive motor adjusts its speed according to the correction signal to restore the Y-axis position of the moving platform 6 to the target value. The entire correction process is completed within 10 milliseconds, ensuring a high degree of consistency between the welding trajectory and the preset path. During welding, an infrared temperature sensor collects the instantaneous temperature of the welding area at a frequency of 100 Hz. The parameter optimization unit calculates the thermal deformation compensation amount in real time using a discrete integral formula and superimposes it onto the positioning system, effectively compensating for dimensional errors caused by thermal expansion. During the cooling phase after welding, the compensation amount automatically adjusts as the temperature decreases, further ensuring the dimensional accuracy after welding.

[0067] After 8 hours of continuous welding operations, the maintenance management module initiated welding head wear detection during equipment standby. The laser displacement sensor scanned the welding head end face and obtained a wear area of ​​2.5 square millimeters and a wear depth of 0.15 millimeters. Based on the tool remaining life calculation model, the remaining tool life was calculated. The remaining lifespan is sufficient, requiring no replacement. Simultaneously, the automatic cleaning unit, based on monitoring data from the optical element contamination sensor, determines the contamination level to be 0.35. The automatic cleaning frequency adjustment model calculates the cleaning frequency to be 1 × (1 + 2.0 × 0.35) = 1.7 times / hour. The automatic cleaning unit initiates the cleaning program, first blowing away loose particles with an air pressure nozzle, then wiping the optical element surface with a rotating wiping head. The entire cleaning process lasts 15 seconds, after which the contamination level drops below 0.1. Through multiple safety mechanisms and intelligent management, the system stability index S of this embodiment of the invention is ≥99.5%. The calculation formula for the system stability index is:

[0068] ;

[0069] in Normal working hours are expressed in hours (h). Total running time, in hours (h); For the first The impact coefficient of the secondary failure (ranging from 0.5 to 1.0, determined according to the severity of the failure); For the first The downtime for each fault is expressed in hours (h). The numerator and denominator of this formula are both time units, and the result is a percentage with a clear physical meaning.

[0070] The width of the heat-affected zone (HAZ) in laser welding is a crucial indicator of weld quality. This invention optimizes welding parameters to minimize the HAZ width. According to the heat conduction theory of a moving point heat source, the approximate formula for calculating the width of the heat-affected zone is:

[0071] ;

[0072] in The width of the heat-affected zone is expressed in meters (m). The thermal diffusivity of the material is expressed in square meters per second (m² / s). The laser spot diameter is expressed in meters (m). The welding speed is expressed in meters per second (m / s). The melting point of the material is expressed in Kelvin (K). The ambient temperature is expressed in Kelvin (K). This is the critical temperature of the heat-affected zone (approximately 573K, the recrystallization temperature for aluminum alloys). Dimensional analysis is as follows: The unit of measurement is consistent with the unit of length. Taking the welding of aluminum alloy 6061 as an example, the thermal diffusivity... Spot diameter Welding speed v Melting point Given an ambient temperature T0 = 298K, substituting this into the calculation yields:

[0073] It meets the quality requirements for welding precision parts.

[0074] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0075] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An intelligent laser welding device for parts processing, comprising a base (2), characterized in that, The base (2) has a protective cover (1) installed at the top of its rear end, a movable seat (5) installed at the top of its front end, a movable platform (6) installed at the top of the movable seat (5), a control component (4) installed on the left side of the base (2), an alarm (3) installed at the top of the left side of the protective cover (1), a tool holder (7) installed inside the left side of the protective cover (1), a first drive assembly (8) installed inside the protective cover (1), a second drive assembly (9) installed on the outer wall of the first drive assembly (8), and a laser welding machine (10) installed on the outer wall of the second drive assembly (9). The control component (4) integrates a safety monitoring module, a positioning feedback module, an intelligent control module, and a maintenance management module. The four functional modules communicate with each other through a data bus to form a complete closed-loop control system from safety monitoring to positioning feedback, to intelligent control, and finally to maintenance management.

2. The intelligent laser welding equipment for parts processing according to claim 1, characterized in that, The safety monitoring module includes a laser beam offset sensor, a radiation intensity sensor, an ambient temperature sensor, and a visual monitoring component. The laser beam offset sensor is magnetically mounted on the inner wall of the protective cover (1), with its probe facing the welding area. The radiation intensity sensor is arranged around the welding area via a threaded connection, with its probe facing the laser emission direction of the laser welding machine (10). The ambient temperature sensor is arranged around the welding point, with its probe in close contact with the welding area via thermal grease. The visual monitoring component is fixedly mounted inside the protective cover (1) via a bracket and includes a high-speed camera and an illumination source.

3. The intelligent laser welding equipment for parts processing according to claim 2, characterized in that, The safety monitoring module calculates the safety risk index of the welding area based on three key parameters: laser beam offset, radiation intensity and ambient temperature, and outputs different early warning signals to the alarm (3) according to the difference in the level of the safety risk index.

4. The intelligent laser welding equipment for parts processing according to claim 1, characterized in that, The positioning feedback module includes a high-precision position sensor and a closed-loop control unit. The high-precision position sensor is embedded in the bottom of the mobile platform (6) and is designed using the principle of a grating ruler. It collects the three-dimensional position coordinate data and rotation angle data of the mobile platform (6) in real time. The closed-loop control unit has a built-in PID control algorithm. It receives the actual position information fed back by the position sensor and compares it with the preset target position to calculate the position deviation value and generate a correction signal, which is then transmitted to the drivers of the first drive component (8) and the second drive component (9).

5. The intelligent laser welding equipment for parts processing according to claim 4, characterized in that, The first drive assembly (8) and the second drive assembly (9) both adopt the structure of servo motor plus ball screw. The servo motor is connected to the power input end of the ball screw through a coupling. The screw nut of the ball screw is fixedly connected to the driven object. The first drive assembly (8) and the second drive assembly (9) are connected through a coupling to form a multi-axis linkage system, which is uniformly coordinated and controlled by the control component (4).

6. The intelligent laser welding equipment for parts processing according to claim 1, characterized in that, The intelligent control module includes a material property identification unit and a parameter optimization unit. The material property identification unit is equipped with a spectral analysis device to determine the material type and thickness information of the workpiece by identifying the reflectance spectral characteristics of the workpiece surface. The parameter optimization unit has a built-in library of welding process parameters for different materials and automatically adjusts the laser power and focusing position according to the material properties and environmental parameters.

7. The intelligent laser welding equipment for parts processing according to claim 6, characterized in that, The parameter optimization unit can calculate the thermal deformation compensation amount in real time based on the temperature change data of the welding area, and superimpose the compensation amount onto the target position of the positioning feedback module to realize dynamic compensation of thermal deformation during the welding process.

8. The intelligent laser welding equipment for parts processing according to claim 1, characterized in that, The maintenance management module includes a tool condition monitoring unit and an automatic cleaning unit. The tool condition monitoring unit collects wear area and wear depth data of the welding head through a wear sensor installed near the laser welding head, and calculates the remaining tool life. The automatic cleaning unit is equipped with a contamination level monitoring sensor and a cleaning actuator, and adjusts the cleaning frequency according to the contamination level of the optical component surface.

9. The intelligent laser welding equipment for parts processing according to claim 1, characterized in that, The alarm (3) is equipped with a warning light and a buzzer. The warning light includes a yellow light source and a red light source. The alarm (3) has three warning levels: the yellow warning light is lit continuously in the low-risk state, the yellow warning light is lit and accompanied by intermittent buzzing in the medium-risk state, and the red warning light is lit and accompanied by continuous buzzing in the high-risk state, while sending a cut-off signal to the control unit (4).

10. The intelligent laser welding equipment for parts processing according to claim 1, characterized in that, The tool holder (7) adopts a modular design. The overall frame is made of aluminum alloy and has multiple standardized tool storage positions. Each storage position is equipped with an electromagnetic induction position sensor. The control component (4) can determine whether a tool is stored in the storage position and the type of tool stored based on the signal from the position sensor. It works with the drive component to achieve automatic identification and quick replacement of the welding head.

Images