Laser flame hybrid spray gun device

Abstract

This invention discloses a laser-flame composite spraying gun device, belonging to the technical field of flame spraying equipment. The device includes a laser output head, a spray gun end, and sequentially connected output head connecting cylinder, beam lens cylinder, fuel input cylinder, and spray gun body. An internal through-guide groove is provided, within which a lens assembly system and a combustion mechanism are installed. A soft-circuit control system is also configured. The lens assembly system optimizes laser transmission, the combustion mechanism ensures fuel mixing and powder delivery, and the soft-circuit control system dynamically and adaptively adjusts laser parameters through difference analysis and algorithm calculations, forming a closed-loop control. This device achieves efficient composite heating of laser and flame, solving the problems of weak coating adhesion and high porosity in traditional flame spraying, and improving powder deposition rate.

Description

Technical Field

[0001] This invention relates to the field of flame spraying equipment technology, and in particular to a laser flame composite spraying gun device. Background Technology

[0002] Flame spraying is a commonly used thermal spraying process for preparing functional coatings on the surface of workpieces in aerospace, energy and power and other fields. It is widely used due to its advantages of low equipment cost and flexible operation. The core process is to use fuel and oxygen to mix and burn to form a high-temperature flame, which heats and accelerates the sprayed powder to the surface of the workpiece to form a coating.

[0003] Traditional flame spray guns consist only of a fuel supply component, a gun body, and a spray nozzle. The flame energy density is limited, and it can only melt the surface of the powder, failing to fully melt the workpiece substrate. This results in the coating and substrate being mechanically bonded with extremely low adhesion. At the same time, uneven powder melting and insufficient airflow velocity can easily lead to excessively high porosity inside the coating.

[0004] Some improved devices attempt to introduce laser-assisted heating, but they simply superimpose the laser beam path and the flame channel without optimizing the design of laser transmission, fuel mixing and powder delivery, or dynamically monitoring the flame state and adaptively adjusting the laser parameters. This makes it difficult to compensate for heating deviations caused by fluctuations in flame conditions and fails to meet the requirements of high-end equipment for the preparation of coatings with high adhesion and low porosity. There is an urgent need to make targeted improvements to the spray gun structure and heating control method. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by proposing a laser-flame composite spray gun device.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a laser flame composite spraying gun device, comprising a laser output head and a spray gun end, wherein an output head connecting cylinder is sleeved around the rear end of the laser output head, a beam lens cylinder is installed at the rear end of the output head connecting cylinder, a fuel input cylinder is installed at the rear end of the beam lens cylinder, and a spray gun body is installed at the rear end of the fuel input cylinder. The spray gun body is located at the front end of the spray gun end, and the laser output head, output head connecting cylinder, beam lens cylinder, fuel input cylinder, spray gun body, and spray gun end are provided with interconnected guide grooves. A lens group system for laser transmission shaping and a combustion mechanism for combustion spraying are installed in the guide grooves, and the lens group system for laser transmission shaping is located at the front end of the combustion mechanism.

[0007] It is also equipped with a soft-connection control system, which is used to monitor the characteristic differences between the high-temperature flame generated by the fuel-oxygen ratio and the preset standard flame, and to perform dynamic linear adaptive compensation control on the laser-assisted heating parameters of the laser output head based on the characteristic differences to ensure the spraying effect. The soft-connection control system includes a data acquisition module, a data analysis and processing module, and an execution control module. The modules are interconnected and sequentially complete the acquisition of flame characteristics, difference analysis and compensation algorithm calculation, and execution adjustment of laser parameters.

[0008] Preferably, the laser transmission shaping lens system includes a scattering end, a convex mirror, a concave mirror, and a condenser mirror installed in the guide groove. The scattering end is located on the inner wall of the rear end of the laser output head. The convex mirror, concave mirror, and condenser mirror are installed sequentially from front to back on the inner wall of the beam lens tube, and the optical centers of the scattering end, convex mirror, concave mirror, and condenser mirror coincide with the central axis of the guide groove.

[0009] Preferably, the combustion mechanism includes a gas guide end located inside the fuel input cylinder. The gas guide end has a conical structure, and the fuel input cylinder has two fuel inlets for respectively introducing oxygen and fuel. The fuel inlets communicate with the interior of the guide groove, and the two fuel inlets are symmetrically distributed around the periphery of the fuel input cylinder.

[0010] Preferably, the guide groove is located inside the spray gun body and is a Laval structure, with the front diameter being larger than the rear diameter, and the front end of the spray gun body is a segmented variable diameter rotating body structure, with the diameter of each segment of the segmented variable diameter rotating body decreasing sequentially along the axial direction.

[0011] Preferably, the combustion mechanism further includes multiple powder inlets equidistantly and obliquely opened on the end of the spray gun, and a powder channel and a powder buffer cavity are opened between the spray gun body and the inner wall of the spray gun end, with the powder buffer cavity located between the powder inlets and the powder channel.

[0012] Preferably, the powder inlet, powder buffer chamber, and powder channel are interconnected, and the other end of the powder channel is connected to the inside of the guide groove. The powder channel extends in an arc shape along the inner wall of the spray gun body to the outlet end of the guide groove.

[0013] Preferably, the cone tip of the gas guide end faces the rear end of the guide groove, and an annular fuel channel is formed between the outer wall of the gas guide end and the inner wall of the fuel input cylinder, and the annular fuel channel is connected to the fuel inlet;

[0014] The data acquisition module is located on the outside of the nozzle tip and faces the direction of the high-temperature flame. The data acquisition module includes a multi-dimensional flame feature sensor group for collecting real-time feature parameters of the high-temperature flame. The real-time feature parameters include at least flame shape parameters, flame temperature parameters, and flame length parameters. The acquisition signals from each sensor are synchronously transmitted to the data analysis and processing module.

[0015] Preferably, the data analysis and processing module has a built-in preset standard flame feature database, a difference analysis unit, and a dynamic linear adaptive compensation algorithm calculation unit.

[0016] The preset standard flame feature database stores standard threshold ranges and standard feature curves for flame shape, temperature, and length that match the spraying process.

[0017] The difference analysis unit is used to compare the real-time feature parameters transmitted by the data acquisition module with the feature parameters of the preset standard flame, calculate the difference values ​​of each feature dimension, and form a multi-dimensional flame feature difference matrix.

[0018] The dynamic linear adaptive compensation algorithm calculation unit, based on the multi-dimensional flame feature difference matrix and combined with the dynamic influencing factors in the spraying process, calculates the compensation parameters for laser-assisted heating through the dynamic linear adaptive compensation algorithm. The dynamic influencing factors include at least the type of spraying powder, the material of the workpiece substrate, and the relative motion speed between the spray gun and the workpiece. The compensation parameters include at least the laser power, the laser output frequency, and the laser spot size.

[0019] Preferably, the dynamic linear adaptive compensation algorithm uses the total difference in flame characteristics as input and the laser-assisted heating compensation parameters as output to establish a dynamic linear adaptive control model. Specifically, it first constructs a calculation model for the total difference in flame characteristics, normalizes the difference values ​​of each dimension, and assigns process weights, as shown in the formula: ;

[0020] In the formula, D represents the total difference in flame features, and n represents the number of dimensions of flame features. Let be the process weight of the i-th feature dimension, and , Let be the real-time acquired parameters for the i-th feature dimension. These are the preset standard parameters for the i-th feature dimension;

[0021] Secondly, a dynamic linear adaptive compensation control model is established. Based on the total difference in flame characteristics and the correction coefficients of dynamic influencing factors, the adjustment amount of the laser compensation parameters is calculated. The formula is as follows: In the formula, Let j be the adjustment amount of the j-th laser compensation parameter. Let p be the scaling factor for the j-th laser compensation parameter, and p be the number of dynamic influencing factors. This is the correction coefficient for the m-th dynamic influencing factor;

[0022] The final target parameters for laser output are obtained as follows: In the formula, Let j be the target value of the laser compensation parameter. This is the initial reference value for the j-th laser compensation parameter.

[0023] Preferably, the execution control module is electrically connected to the laser generating unit of the laser output head and is also signal-connected to the data analysis and processing module. The execution control module receives the target value of the laser compensation parameter transmitted by the data analysis and processing module, converts it into an electrical control signal and outputs it to the laser generating unit to realize real-time adjustment of laser power, laser output frequency and laser spot size.

[0024] The execution control module also has a built-in feedback adjustment unit, which is used to collect the actual laser output parameters of the laser output head and compare them with the target parameters. If there is a deviation, a secondary fine adjustment is performed to form a closed-loop dynamic linear adaptive control of acquisition-analysis-execution-feedback. The secondary fine adjustment amount is calculated based on the deviation value between the actual output parameters and the target parameters, and the adjustment rate of the secondary fine adjustment is positively correlated with the deviation value.

[0025] Compared with the prior art, the beneficial effects of the present invention are:

[0026] 1. This solution utilizes a scattering end, convex mirror, concave mirror, and condenser mirror in combination to scatter, focus, and shape the laser, thereby improving laser energy density and transmission accuracy. Simultaneously, a conical gas guide end and annular fuel channel work together to ensure thorough mixing and combustion of fuel and oxygen, increasing flame energy density and achieving composite heating of laser and high-temperature flame. Compared to the limited flame energy density of traditional flame spraying, this composite heating method can fully melt the workpiece substrate surface, changing the current situation where the coating and substrate are only mechanically bonded, and achieving a (quasi)metallurgical bond between the coating and substrate. This solves the technical problem of extremely low adhesion between the coating and substrate in traditional processes, optimizing the basic conditions for coating bonding from the heating source level.

[0027] 2. This solution features a powder inlet at the spray gun tip, combined with a powder buffer chamber and an arc-shaped powder channel between the spray gun body and the inner wall of the tip. The negative pressure generated by the high-speed flame airflow ensures automatic and continuous powder delivery, guaranteeing stable powder supply. Simultaneously, the spray gun body employs a segmented variable-diameter rotating structure, with the guide groove designed to be thicker at the front and thinner at the back, accelerating the flame airflow and increasing powder spraying speed. Addressing the issues of uneven powder melting and insufficient airflow velocity in traditional flame spraying, the stable powder supply combined with high-speed airflow allows the powder to melt fully and uniformly in the composite heating field, reducing porosity caused by insufficient powder melting and slow deposition rates within the coating, thus resolving the technical defect of excessively high coating porosity.

[0028] 3. This solution is equipped with a soft-connected control system consisting of data acquisition, data analysis and processing, and execution control modules. It collects real-time parameters such as flame shape, temperature, and length through multi-dimensional sensors, obtains laser compensation parameters through difference analysis and algorithm calculation, and then adjusts the laser parameters by the execution control module. A feedback adjustment unit forms a closed-loop control. Compared to the improved device that simply superimposes the laser and flame channels without dynamic adjustment, this system can monitor flame condition deviations in real time and dynamically and linearly adaptively compensate for laser heating parameters based on dynamic influencing factors in spraying. This ensures that the composite heating effect always matches the spraying process requirements, avoids underheating or overheating caused by flame condition fluctuations, improves powder deposition rate, and meets the precision requirements of high-end equipment for spraying processes.

[0029] In summary, this solution achieves efficient composite heating of laser and flame by optimizing the laser transmission structure, fuel mixing structure, and powder conveying structure. Simultaneously, the soft-control system enables closed-loop dynamic adaptive adjustment of flame conditions and laser parameters, fundamentally solving the problems of weak adhesion and high porosity in traditional flame-sprayed coatings. It also compensates for the lack of dynamic adjustment in improved devices, achieving uniform melting and high-speed deposition of powder, increasing the powder deposition rate, and ensuring that the sprayed coating meets the requirements of high-end equipment for high adhesion and low porosity. This optimizes the overall process effect and product quality of flame spraying. Attached Figure Description

[0030] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0031] Figure 1 This is a schematic diagram of the overall appearance of the device proposed in this invention;

[0032] Figure 2 This is a schematic diagram of the overall cross-sectional structure of the device proposed in this invention;

[0033] Figure 3 The present invention proposes Figure 2 Enlarged schematic diagram of the structure at part A in the middle;

[0034] Figure 4 The present invention proposes Figure 2 Enlarged schematic diagram of the structure of part B in the middle;

[0035] Figure 5 This is an overall connection block diagram of the Softcom control system proposed in this invention;

[0036] Figure 6 This is a block diagram of the dynamic linear adaptive compensation control principle proposed in this invention;

[0037] Figure 7 This is a block diagram of the internal logic of the data analysis and processing module proposed in this invention.

[0038] The numbers in the diagram are: 1. Laser output head; 2. Spray gun end; 3. Output head connecting tube; 4. Beam lens tube; 5. Fuel input tube; 6. Spray gun body; 7. Scattering end; 8. Convex mirror; 9. Concave mirror; 10. Condensing mirror; 11. Gas guiding end; 12. Fuel inlet; 13. Powder inlet; 14. Powder channel; 15. Powder buffer chamber. Detailed Implementation

[0039] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0040] See Figures 1 to 7This invention discloses a laser-flame composite spray gun device, comprising a laser output head 1 and a spray gun end 2. The laser output head 1 facilitates the installation of an output optical fiber, with one end of the output optical fiber connected to a scattering end 7. The spray gun end 2 is generally a QBH structure (but can also be QD, LOE, etc.). An output head connecting sleeve 3 is sleeved around the rear end of the laser output head 1, facilitating the connection between the laser output head 1 and a beam lens tube 4. A beam lens tube 4 is installed at the rear end of the output head connecting sleeve 3, facilitating placement and... Various optical lenses are fixed in place; a fuel input cylinder 5 is installed at the rear end of the beam lens tube 4, through which a fuel inlet 12 is easily opened to deliver fuel and oxygen into the guide groove, which then cooperates with the laser to generate high-temperature combustion; a spray gun body 6 is installed at the rear end of the fuel input cylinder 5, which serves as the combustion chamber for fuel and oxygen. After the fuel and oxygen burn, a high-pressure flame is generated, forming a high-speed airflow that drives the powder to form a high-speed powder flow. The fuel can be propane, acetylene, propylene, hydrogen, methane, gasoline, kerosene, etc.; the spray gun body 6 is located at the front end of the spray gun end 2, and the laser output head 1, output head connecting cylinder 3, beam lens tube 4, fuel input cylinder 5, spray gun body 6, and spray gun end 2 are interconnected with guide grooves. A lens group system for laser transmission and shaping and a combustion mechanism for combustion spraying are installed in the guide grooves. The lens group system for laser transmission and shaping facilitates the collimation, compression, and shaping of the laser beam so that it can pass through the spray gun end 2 and reach the surface of the workpiece substrate; the combustion mechanism facilitates the use of the energy generated by fuel combustion to heat the powder. High-speed (subsonic or supersonic) jetting; the laser transmission and shaping lens system is located at the front end of the combustion mechanism. The laser transmission and shaping lens system includes a scattering end 7, a convex mirror 8, a concave mirror 9, and a focusing mirror 10 installed in the guide groove. The scattering end 7 facilitates the divergence and shaping of the laser emitted from the optical fiber and the laser output head 1; the convex mirror 8 facilitates the rescattering of the laser; the concave mirror 9 focuses the scattered laser into a laser beam, and when it passes through the focusing mirror 10, the gas guiding end 11 plays a guiding and airflow constraint role.The scattering end 7 is located on the inner wall of the rear end of the laser output head 1. A convex mirror 8, a concave mirror 9, and a condenser lens 10 are sequentially installed from front to back on the inner wall of the beam lens tube 4. The optical centers of the scattering end 7, convex mirror 8, concave mirror 9, and condenser lens 10 coincide with the central axis of the guide groove. The combustion mechanism includes a gas guiding end 11 located inside the fuel input tube 5. The gas guiding end 11 has a conical structure, and the fuel input tube 5 has two fuel inlets 12 for respectively introducing oxygen and fuel. The fuel inlets 12 facilitate the addition of fuel and oxygen into the guide groove, where they mix with the laser after combustion. During the spraying process, the mixture of laser and fuel... While the flame melts the powder, the high energy density of the laser can also be used to rapidly melt the surface of the workpiece substrate, thereby achieving a (quasi)metallurgical bond between the coating and the substrate. Compared with simple flame spraying, this not only improves the coating adhesion but also significantly reduces the coating porosity and increases the powder deposition rate. The fuel inlet 12 is connected to the inside of the guide groove, and the two fuel inlets 12 are symmetrically distributed around the fuel input cylinder 5. The diameter of the front end of the guide groove located inside the spray gun body 6 is larger than the diameter of the rear end, and the front end of the spray gun body 6 is a segmented Laval structure, with the diameter of each segment decreasing sequentially along the axial direction.

[0041] In this invention, the combustion mechanism also includes multiple powder inlets 13 equidistantly and obliquely opened on the spray gun end 2. Powder is easily added through the powder inlets 13, and then the powder enters the powder buffer chamber 15. When the laser and flame pass through, a negative pressure is generated. This negative pressure drives the powder from the powder buffer chamber 15 through the powder channel 14 to the output end of the spray gun end 2, thereby melting the powder at high temperature and spraying it onto the surface of the workpiece substrate. A powder channel 14 and a powder buffer chamber 15 are provided between the spray gun body 6 and the inner wall of the spray gun end 2. The powder buffer chamber 15 is located between the powder inlets 13 and the powder channel. Between 14, the powder inlet 13, the powder buffer chamber 15, and the powder channel 14 are interconnected, and the other end of the powder channel 14 is connected to the inside of the guide groove. The powder channel 14 extends in an arc along the inner wall of the spray gun body 6 to the outlet end of the guide groove. The cone tip of the gas guide end 11 faces the rear end of the guide groove. This structure ensures that the powder buffer chamber 15 can store powder while also using negative air pressure to transport powder to the output end of the spray gun end 2. Furthermore, an annular fuel channel is formed between the outer wall of the gas guide end 11 and the inner wall of the fuel input cylinder 5, and the annular fuel channel is connected to the fuel inlet 12.

[0042] The data acquisition module is located on the outside of the nozzle end 2 and faces the direction of the high-temperature flame. The data acquisition module includes a multi-dimensional flame characteristic sensor group, which is used to collect real-time characteristic parameters of the high-temperature flame. The real-time characteristic parameters include at least flame shape parameters, flame temperature parameters, and flame length parameters. The acquisition signals of each sensor are synchronously transmitted to the data analysis and processing module.

[0043] Specifically, the data analysis and processing module has a built-in preset standard flame feature database, a difference analysis unit, and a dynamic linear adaptive compensation algorithm calculation unit;

[0044] The preset standard flame feature database stores standard threshold ranges and standard feature curves for flame shape, flame temperature, and flame length that match different spraying processes. The standard feature curves are correlation curves of various flame feature parameters with changes in spraying process parameters such as spraying powder particle size, spraying distance, and fuel type. Specifically, they can be retrieved, updated, and modified according to the actual spraying process requirements to achieve precise matching with the spraying process.

[0045] After receiving the flame shape, temperature, and length characteristic parameters transmitted in real time by the data acquisition module, the difference analysis unit first retrieves the standard flame characteristic parameters consistent with the current spraying process from the preset standard flame characteristic database. Then, it compares the real-time characteristic parameters with the standard characteristic parameters dimension by dimension and calculates the absolute difference value of each characteristic dimension. The calculation formula is: In the formula, Let be the real-time acquired parameters for the i-th feature dimension. Let be the preset standard parameters for the i-th feature dimension. These correspond to the characteristic dimensions of flame shape, flame temperature, and flame length, respectively.

[0046] After calculating the difference values ​​for each dimension, the difference analysis unit sorts the difference values ​​by feature dimension and constructs a multi-dimensional flame feature difference matrix M, the matrix expression of which is: ;in, These represent the absolute differences between the flame shape, flame temperature, and flame length and the preset standard parameters, respectively. This matrix intuitively reflects the degree of deviation between each characteristic dimension of the high-temperature flame and the preset standard flame, providing basic data support for subsequent compensation algorithm calculations.

[0047] The dynamic linear adaptive compensation algorithm calculation unit is based on a multi-dimensional flame feature difference matrix and combines the dynamic influencing factors in the spraying process. It calculates the compensation parameters for laser-assisted heating through the dynamic linear adaptive compensation algorithm. The dynamic influencing factors include at least the type of spraying powder, the material of the workpiece substrate, and the relative motion speed between the spray gun and the workpiece. The compensation parameters include at least the laser power, the laser output frequency, and the laser spot size.

[0048] Specifically, the dynamic linear adaptive compensation algorithm uses the total difference in flame characteristics as input and the laser-assisted heating compensation parameters as output to establish a dynamic linear adaptive control model, as follows:

[0049] First, a model for calculating the total difference in flame characteristics is constructed. The difference values ​​of each dimension are normalized and assigned process weights. The formula is as follows: ;

[0050] In the formula, D represents the total difference in flame features, and n represents the number of dimensions of flame features. Let be the process weight of the i-th feature dimension, and , Let be the real-time acquired parameters for the i-th feature dimension. These are the preset standard parameters for the i-th feature dimension;

[0051] Secondly, a dynamic linear adaptive compensation control model is established. Based on the total difference in flame characteristics and the correction coefficients of dynamic influencing factors, the adjustment amount of the laser compensation parameters is calculated. The formula is as follows: In the formula, Let j be the adjustment amount of the j-th laser compensation parameter. Let p be the scaling factor for the j-th laser compensation parameter, and p be the number of dynamic influencing factors. This is the correction coefficient for the m-th dynamic influencing factor;

[0052] It should be added that, Let be the process weight for the i-th feature dimension. The logic for obtaining this weight is as follows: based on the influence of flame shape, flame temperature, and flame length on the spraying heating effect and coating quality, the contribution ratio of each dimension is determined through orthogonal experiments or process calibration experiments, and then normalized. Alternatively, weights can be assigned based on historical spraying process data using the Analytic Hierarchy Process (AHP) or expert scoring method to reflect the differentiated impact of different feature dimensions on the spraying effect.

[0053] Let be the proportional coefficient of the j-th laser compensation parameter. Its acquisition logic is as follows: Through calibration experiments, test the response sensitivity of laser power, laser output frequency, and laser spot size to the flame heating compensation effect, and establish the relationship between the total difference in flame characteristics D and the laser parameter adjustment amount. The linear mapping relationship between them, the slope of which is... Alternatively, it can be determined through system identification methods based on the PID control principle. This allows the laser parameter adjustment to respond quickly to differences in the flame while avoiding system oscillations caused by over-adjustment;

[0054] This is the correction coefficient for the m-th dynamic influencing factor. Its acquisition logic is as follows: For dynamic factors such as the type of spray powder, the substrate material of the workpiece, and the relative speed between the spray gun and the workpiece, single-factor variable experiments are conducted to test the correlation between the differences in flame characteristics and the laser compensation effect under different working conditions. The actual compensation effect under each working condition is compared with the baseline working condition (default correction coefficient). The ratio of the two factors can be used as the correction coefficient for the corresponding factor; alternatively, it can be obtained by training a machine learning model with dynamic influencing factors as input and laser compensation efficiency as output. This enables adaptive correction for different operating conditions;

[0055] The final target parameters for laser output are obtained as follows: In the formula, Let j be the target value of the laser compensation parameter. The initial reference value for the j-th laser compensation parameter; As a compensation parameter for laser-assisted heating, the data analysis and processing module can achieve precise analysis of flame characteristic differences and dynamic, adaptive calculation of laser compensation parameters through the above settings, providing data basis for subsequent precise adjustment of laser parameters.

[0056] Specifically, the execution control module, as the execution end of the soft-connect control system, achieves precise electrical connection with the laser generation unit of laser output head 1, while maintaining bidirectional high-speed signal communication with the data analysis and processing module. Its core functions include signal conversion, execution adjustment, and feedback correction of laser compensation parameters. The specific working mode and settings are as follows:

[0057] Signal conversion and real-time adjustment of laser parameters:

[0058] The execution control module receives target values ​​for three types of compensation parameters—laser power, laser output frequency, and laser spot size—transmitted by the data analysis and processing module. Then, through the built-in digital-to-analog conversion unit, the target parameter values ​​in digital form are converted into analog electrical control signals that are compatible with the laser generator unit's drive circuit. The amplitude and frequency of the electrical control signal are linearly related to the target value of the laser compensation parameters. After the electrical control signal is output to the corresponding drive module of the laser generator unit, it enables independent, real-time, and linear precise adjustment of the laser power, laser output frequency, and laser spot size, ensuring that the laser-assisted heating parameters can achieve rapid response compensation according to the differences in flame characteristics.

[0059] The feedback adjustment unit, built into the closed-loop control execution control module, is electrically connected to the laser parameter detection component of the laser output head 1. The laser parameter detection component is a combination of a laser power meter, a laser frequency detector, and a spot size detector, used to collect real-time actual output parameters of the laser output head 1, including laser power, laser output frequency, and laser spot size. The feedback adjustment unit will collect the actual output parameters Target parameters transmitted with the data analysis and processing module By performing a dimensional deviation calculation, the deviation values ​​of each laser parameter are obtained. The calculation formula is: In the formula, These correspond to the dimensions of laser power, laser output frequency, and laser spot size, respectively. The feedback adjustment unit stores preset deviation thresholds for each laser parameter. The feedback adjustment unit will calculate the deviation value. Deviation threshold from preset Comparison:

[0060] like The actual laser output parameters are determined to meet the compensation requirements, and no adjustment is needed.

[0061] like If the actual laser output parameters are found to deviate significantly from the target parameters, the feedback adjustment unit will initiate a secondary linear fine-tuning procedure.

[0062] Algorithm and execution of the quadratic linear fine-tuning program:

[0063] The second linear fine-tuning amount of the feedback adjustment unit Based on deviation value and fine-tuning ratio coefficient The calculation is as follows: In the formula, This is the fine-tuning ratio coefficient for the j-th laser parameter, and its value is set according to the adjustment accuracy and response characteristics of the laser generating unit. The positive correlation coefficient ensures that the fine-tuning amount is positively correlated with the deviation value, achieving a linear fine-tuning effect where the larger the deviation, the more suitable the adjustment range becomes; This is the fine-tuning proportional coefficient for the j-th laser parameter, and its value is obtained by performing a step response test on the laser generating unit: the actual adjustment accuracy and response delay of the laser parameter are tested under different deviation values ​​to establish the deviation value. With target fine-tuning amount The linear fitting model has a slope of the fitted line as its linearity. Alternatively, it can be determined using empirical formulas based on parameters such as the minimum adjustment step size and maximum response frequency of the laser generating unit. Calculated to ensure The positive correlation coefficient ensures that the fine-tuning amount and the deviation value are linearly positively correlated, balancing adjustment accuracy and response speed.

[0064] The feedback adjustment unit adjusts the secondary fine-tuning amount calculated by the feedback adjustment unit. The corresponding fine-tuning electrical control signal is generated and output to the laser generating unit to perform precise secondary correction on the laser parameters. After correction, the actual output parameters are collected again through the laser parameter detection component, and the above deviation calculation and comparison steps are repeated until... Complete a single feedback adjustment;

[0065] Through the above settings, the execution control module realizes a closed-loop control of the entire process of receiving, converting, executing, feeding back, and correcting laser compensation parameters. Combined with the flame feature acquisition by the data acquisition module and the difference analysis and compensation parameter calculation by the data analysis and processing module, a complete closed-loop dynamic linear adaptive control system of acquisition, analysis, execution, and feedback is finally formed. This ensures the compensation accuracy and real-time performance of laser-assisted heating, and ensures that the combined heating effect of high-temperature flame and laser always matches the requirements of the spraying process, effectively guaranteeing the adhesion and density of the sprayed coating.

[0066] It should be further explained that the multi-dimensional flame feature sensor group includes a visual imaging sensor, an infrared temperature sensor, and a laser rangefinder. The visual imaging sensor is used to acquire flame contour images and analyze them to obtain numerical parameters of flame shape and length. The infrared temperature sensor is used to acquire real-time temperature distribution parameters of different areas of the flame. The acquisition frequency of each sensor is adapted to the dynamic change rate of the spraying process to achieve continuous real-time acquisition of flame features.

[0067] Each module of the soft-control mechanism is integrated in the control box on the outside of the spray gun body 6, or remotely connected to an external industrial control computer. The control box is equipped with a parameter interaction interface for manually inputting spraying process parameters, modifying preset standard flame characteristic parameters, and adjusting the correction coefficients of dynamic influencing factors.

[0068] The working principle of this device is as follows:

[0069] In operation, the laser output head 1 is first connected to an external laser source via an output optical fiber, ensuring stable laser transmission to the scattering end 7. Simultaneously, oxygen and fuel are introduced into the annular fuel channel through the symmetrical fuel inlets 12 on the fuel input cylinder 5, where they are thoroughly mixed within the guide groove. The spray powder is then added from the powder inlet 13 at the spray gun end 2, temporarily stored in the powder buffer chamber 15, and then moved along the arc-shaped powder channel 14 towards the guide groove outlet under the negative pressure generated by the high-speed gas flow of the flame. After the laser source is activated, the laser is scattered by the scattering end 7, and then sequentially passes through the convex mirror 8, concave mirror 9, condenser mirror 10, and conical gas guide end 11 within the beam lens cylinder 4 to complete scattering, focusing, and compression shaping, forming a high-energy laser beam. Simultaneously, the mixed fuel is ignited, burning within the segmented variable-diameter rotating structure of the spray gun body 6, generating a high-temperature, high-pressure flame. The laser beam and the high-temperature flame converge within the guide groove to form a composite heating field.

[0070] The soft-connect control system starts working synchronously. The multi-dimensional flame characteristic sensor group on the outside of the spray gun end 2 collects real-time characteristic parameters such as flame shape, temperature, and length. After being transmitted to the data analysis and processing module, it is compared and analyzed with the preset standard flame characteristic parameters to obtain laser compensation parameters. Then, the execution control module converts the compensation parameters into electrical control signals and outputs them to the laser generation unit of the laser output head 1 to realize real-time adjustment of laser power, output frequency, and spot size. The feedback adjustment unit of the execution control module also collects the actual laser output parameters, compares them with the target parameters, and performs secondary fine-tuning to form a closed-loop control.

[0071] Finally, the composite heating field rapidly and fully melts the powder conveyed by the powder channel 14. The melted powder is then driven by the high-speed flame airflow accelerated by the variable diameter structure of the spray gun body 6, and is sprayed at high speed from the spray gun end 2 onto the surface of the workpiece substrate, realizing the quasi-metallurgical bonding between the coating and the substrate, and completing the spraying operation.

[0072] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A laser-flame composite spray gun device, comprising a laser output head (1) and a spray gun end (2), characterized in that: The laser output head (1) is sleeved with an output head connecting cylinder (3) on its rear side. A beam lens cylinder (4) is installed at the rear end of the output head connecting cylinder (3). A fuel input cylinder (5) is installed at the rear end of the beam lens cylinder (4). A spray gun body (6) is installed at the rear end of the fuel input cylinder (5). The spray gun body (6) is located at the front end of the spray gun end (2). The laser output head (1), the output head connecting cylinder (3), the beam lens cylinder (4), the fuel input cylinder (5), the spray gun body (6), and the spray gun end (2) are provided with interconnected guide grooves. A lens group system for laser transmission shaping and a combustion mechanism for combustion spraying are installed in the guide grooves. The lens group system for laser transmission shaping is located at the front end of the combustion mechanism. It is also equipped with a soft-connection control system, which is used to monitor the characteristic differences between the high-temperature flame generated by the fuel-oxygen ratio and the preset standard flame, and to perform dynamic linear adaptive compensation control on the laser-assisted heating parameters of the laser output head (1) based on the characteristic differences, so as to ensure the spraying effect; the soft-connection control system includes a data acquisition module, a data analysis and processing module and an execution control module, and the signals between the modules are connected, and the flame characteristics are collected, the difference analysis and compensation algorithm calculation are performed, and the laser parameters are executed and adjusted in sequence.

2. The laser-flame composite spray gun device according to claim 1, characterized in that: The laser transmission shaping lens system includes a scattering end (7), a convex mirror (8), a concave mirror (9), and a condenser (10) installed in the guide groove. The scattering end (7) is located on the inner wall of the rear end of the laser output head (1). The convex mirror (8), the concave mirror (9), and the condenser (10) are installed sequentially from front to back on the inner wall of the beam lens tube (4), and the optical centers of the scattering end (7), the convex mirror (8), the concave mirror (9), and the condenser (10) coincide with the central axis of the guide groove.

3. The laser-flame composite spray gun device according to claim 1, characterized in that: The combustion mechanism includes a gas guide end (11) located inside the fuel input cylinder (5). The gas guide end (11) has a conical structure, and the fuel input cylinder (5) has two fuel inlets (12) for respectively introducing oxygen and fuel. The fuel inlets (12) are connected to the inside of the guide groove, and the two fuel inlets (12) are symmetrically distributed around the fuel input cylinder (5).

4. The laser-flame composite spray gun device according to claim 1, characterized in that: The guide groove is located inside the spray gun body (6) and is a Laval structure. The diameter of the front end is larger than that of the rear end. The front end of the spray gun body (6) is a segmented variable diameter rotating body structure. The diameter of each segment of the segmented variable diameter rotating body decreases sequentially along the axial direction.

5. The laser-flame composite spray gun device according to claim 1, characterized in that: The combustion mechanism also includes multiple powder inlets (13) that are equidistantly and obliquely opened on the nozzle end (2). A powder channel (14) and a powder buffer chamber (15) are provided between the nozzle body (6) and the inner wall of the nozzle end (2). The powder buffer chamber (15) is located between the powder inlets (13) and the powder channel (14).

6. The laser-flame composite spray gun device according to claim 5, characterized in that: The powder inlet (13), powder buffer chamber (15) and powder channel (14) are interconnected, and the other end of the powder channel (14) is connected to the inside of the guide groove. The powder channel (14) extends in an arc along the inner wall of the spray gun body (6) to the outlet end of the guide groove.

7. The laser-flame composite spray gun device according to claim 3, characterized in that: The cone tip of the gas guide end (11) faces the rear end of the guide groove, and an annular fuel channel is formed between the outer wall of the gas guide end (11) and the inner wall of the fuel input cylinder (5), and the annular fuel channel is connected to the fuel inlet (12); The data acquisition module is located on the outside of the nozzle end (2) and faces the direction of high-temperature flame spray. The data acquisition module includes a multi-dimensional flame feature sensor group for collecting real-time feature parameters of high-temperature flame. The real-time feature parameters include at least flame shape parameters, flame temperature parameters, and flame length parameters. The acquisition signals of each sensor are synchronously transmitted to the data analysis and processing module.

8. The laser-flame composite spray gun device according to claim 1, characterized in that: The data analysis and processing module has a built-in preset standard flame feature database, a difference analysis unit, and a dynamic linear adaptive compensation algorithm calculation unit. The preset standard flame feature database stores standard threshold ranges and standard feature curves for flame shape, temperature, and length that match the spraying process. The difference analysis unit is used to compare the real-time feature parameters transmitted by the data acquisition module with the feature parameters of the preset standard flame, calculate the difference values ​​of each feature dimension, and form a multi-dimensional flame feature difference matrix. The dynamic linear adaptive compensation algorithm calculation unit, based on the multi-dimensional flame feature difference matrix and combined with the dynamic influencing factors in the spraying process, calculates the compensation parameters for laser-assisted heating through the dynamic linear adaptive compensation algorithm. The dynamic influencing factors include at least the type of spraying powder, the material of the workpiece substrate, and the relative motion speed between the spray gun and the workpiece. The compensation parameters include at least the laser power, the laser output frequency, and the laser spot size.

9. The laser-flame composite spray gun device according to claim 8, characterized in that: The dynamic linear adaptive compensation algorithm uses the total difference in flame characteristics as input and the laser-assisted heating compensation parameters as output to establish a dynamic linear adaptive control model. Specifically, it first constructs a calculation model for the total difference in flame characteristics, normalizes the difference values ​​of each dimension, and assigns process weights, as shown in the formula: ; In the formula, D represents the total difference in flame features, and n represents the number of dimensions of flame features. Let be the process weight of the i-th feature dimension, and , Let be the real-time acquired parameters for the i-th feature dimension. These are the preset standard parameters for the i-th feature dimension; Secondly, a dynamic linear adaptive compensation control model is established. Based on the total difference in flame characteristics and the correction coefficients of dynamic influencing factors, the adjustment amount of the laser compensation parameters is calculated. The formula is as follows: In the formula, Let j be the adjustment amount of the j-th laser compensation parameter. Let p be the scaling factor for the j-th laser compensation parameter, and p be the number of dynamic influencing factors. This is the correction coefficient for the m-th dynamic influencing factor; The final target parameters for laser output are obtained as follows: In the formula, Let j be the target value of the laser compensation parameter. This is the initial reference value for the j-th laser compensation parameter.

10. The laser-flame composite spray gun device according to claim 1, characterized in that: The execution control module is electrically connected to the laser generating unit of the laser output head (1) and is also signal-connected to the data analysis and processing module. The execution control module receives the target value of the laser compensation parameter transmitted by the data analysis and processing module, converts it into an electrical control signal and outputs it to the laser generating unit to realize real-time adjustment of laser power, laser output frequency and laser spot size. The execution control module also has a built-in feedback adjustment unit, which is used to collect the actual laser output parameters of the laser output head (1), compare them with the target parameters, and perform secondary fine-tuning if there is a deviation, forming a closed-loop dynamic linear adaptive control of acquisition-analysis-execution-feedback; the secondary fine-tuning amount is calculated based on the deviation value between the actual output parameters and the target parameters, and the adjustment rate of the secondary fine-tuning is positively correlated with the deviation value.

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