Automatic nano-coating spraying device suitable for complex curved surface

Abstract

The present application relates to the technical field of spraying device, specifically is a kind of nanometer coating automatic spraying device adapting to complex surface, the present application includes: shell, multi-axis flexible mechanical arm, adaptive posture adjusting mechanism, zoned atomizing spray head group, online laser thickness measuring sensor, closed-loop feedback control module, flow precision control valve body, conveying belt and system control unit.The present application realizes five degrees of freedom flexible motion by multi-axis flexible mechanical arm, cooperates with the independent control of zoned atomizing spray head group center and edge nozzle, and accurately fits complex geometric characteristics;While online laser thickness measuring sensor synchronously collects data, and the coating flow, moving speed and atomizing air pressure are dynamically adjusted by closed-loop feedback module, so as to realize instant correction while spraying;Zoned spray head can be differentially operated, main efficient spraying, edge fine supplementary spraying, effectively solve the problems of missing spraying, over-spraying and uneven thickness, and improve the coating forming quality of complex surface workpiece.

Description

Technical Field

[0001] This invention relates to the field of spraying equipment technology, specifically an automatic nano-coating spraying device adapted to complex curved surfaces. Background Technology

[0002] Nano-protective coatings are widely used in high-end manufacturing fields such as aerospace, automobile manufacturing, and electronic devices to improve the overall performance of parts, including corrosion resistance, wear resistance, stain resistance, and water resistance.

[0003] However, existing automatic spraying devices mostly use a Cartesian coordinate robotic arm to carry a spray gun, and perform scanning spraying in a constant pressure feeding and open-loop control manner. This method has the following shortcomings: First, when dealing with complex free-form surfaces and irregularly shaped parts, the robotic arm is difficult to keep the spray gun perpendicular or equidistant from the workpiece surface, resulting in uneven coating thickness distribution. Second, after spraying, quality judgment relies on offline thickness measurement, and the feedback link is seriously lagging, making it impossible to dynamically correct process parameters during spraying, which can easily cause defects such as local over-thickness or missed spraying. Third, a single nozzle is usually used in conjunction with a common pressure regulating valve to control the paint flow rate, which makes it difficult to achieve fine adjustment of multi-angle, zoned or gradient, and the coverage effect on difficult-to-coat areas such as edges, holes, and ridges is poor. Therefore, we propose an automatic nano-coating spraying device that adapts to complex curved surfaces. Summary of the Invention

[0004] The purpose of this invention is to provide an automatic nano-coating spraying device that adapts to complex curved surfaces, so as to solve the problems mentioned in the background art.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] An automated nano-coating spraying device adapted to complex curved surfaces includes: a housing, a multi-axis flexible robotic arm, an adaptive attitude adjustment mechanism, a zoned atomizing nozzle group, an online laser thickness sensor, a closed-loop feedback control module, a flow precision control valve, a conveyor belt, and a system control unit;

[0007] The shell is enclosed to form a closed spraying working chamber, and the conveyor belt is arranged inside the shell for workpiece transportation and station positioning.

[0008] The multi-axis flexible robotic arm is mounted on one side of the housing. A spray head is mounted at the end of the multi-axis flexible robotic arm via the adaptive attitude adjustment mechanism. The partitioned atomizing spray head assembly and the online laser thickness sensor are mounted on the spray head. The online laser thickness sensor is electrically connected to the closed-loop feedback control module. The closed-loop feedback control module is electrically connected to the flow precision control valve body and the system control unit, respectively. The flow precision control valve body is connected to the paint feed end of the partitioned atomizing spray head assembly.

[0009] The system control unit is electrically connected to the multi-axis flexible robotic arm, the conveyor belt, and the partitioned atomizing nozzle group, respectively.

[0010] Preferably, the multi-axis flexible robotic arm includes:

[0011] A support base is fixedly mounted on one side of the conveyor belt;

[0012] The base is fixedly mounted on the support.

[0013] A support, mounted on the base, is rotatable about the vertical axis of the base;

[0014] The intermediate connecting arm is hinged to the support and can move in pitch around the horizontal axis of the support.

[0015] The upper arm seat is hinged to the upper end of the intermediate connecting arm and can perform pitching or swinging movements of the intermediate connecting arm.

[0016] The upper arm pivot is installed at the front end of the upper arm seat and can rotate the upper arm seat axially.

[0017] The spray head is fixed to the end of the upper arm pivot.

[0018] This creates a motion chain with at least five degrees of freedom, enabling the spray head to adjust its position and angle relative to the workpiece surface in real time.

[0019] Preferably, the partitioned atomizing nozzle group includes a central area nozzle and an edge area nozzle. The system control unit controls the opening and closing of the central area nozzle and the edge area nozzle and the spray width individually or in combination according to the shape of the edge, hole or ridge of the workpiece surface.

[0020] Preferably, the online laser thickness sensor is fixedly mounted on the side wall of the spray head and moves synchronously with the spray head. The online laser thickness sensor collects coating thickness data of the sprayed workpiece in real time and transmits it to the closed-loop feedback control module.

[0021] Preferably, the flow precision control valve body is a miniature electromagnetic flow valve. The closed-loop feedback control module outputs a control signal based on the difference between the measured coating thickness and the preset standard thickness. The flow precision control valve body adjusts the paint supply flow of the partitioned atomizing nozzle group in real time, and synchronously corrects the moving speed of the multi-axis flexible robotic arm and the atomizing air pressure of the nozzle.

[0022] Preferably, the conveyor belt includes a belt, a chain, a support, a drive motor, a positioning sensor, and a tensioning device;

[0023] The bracket is fixed to the bottom of the housing. The belt and the chain are linked and arranged on the bracket. The output end of the drive motor is connected to the belt through the chain. The positioning sensor is mounted at the spraying station of the bracket. The tensioning device is installed on the side of the bracket. The positioning sensor is used to detect whether the workpiece has reached the spraying station and transmit the positioning signal to the system control unit.

[0024] Preferably, the system control unit employs an embedded microprocessor, and the system control unit integrates and stores preset spraying parameters and standard coating thickness thresholds.

[0025] The beneficial effects of this invention are:

[0026] 1. By setting up a multi-axis flexible robotic arm and an adaptive attitude adjustment mechanism, the spray head can achieve flexible movement with at least five degrees of freedom. It can adjust its position and angle relative to the workpiece surface in real time. With the independent control of the central area nozzle and the edge area nozzle in the partitioned atomizing nozzle group, it can accurately fit the complex geometric features of the workpiece surface such as edges, holes, and ridges, effectively solving the problems of uneven coating thickness, missed spraying or over-spraying in the curved transition area of ​​traditional spraying devices.

[0027] 2. This invention uses an online laser thickness sensor that moves synchronously with the spray head to collect coating thickness data in real time and transmit it to a closed-loop feedback control module. This module dynamically adjusts the flow rate to precisely control the coating supply flow of the valve body based on the difference between the measured thickness and the preset standard thickness. At the same time, it also links and corrects the moving speed of the multi-axis flexible robotic arm and the atomizing air pressure of the spray head. This closed-loop control strategy of spraying and measuring simultaneously and correcting in real time ensures that the coating thickness is highly consistent throughout the entire workpiece, which significantly improves the forming quality of the nano-coating.

[0028] 3. By setting up a partitioned atomizing nozzle group, the present invention distinguishes between central area nozzles and edge area nozzles. According to the structural characteristics of different areas of the workpiece, the opening and closing of the nozzles and the spray width can be controlled independently or in combination. This enables a differentiated operation mode of efficient and uniform spraying of large-area main areas and fine touch-up spraying of narrow edge and hole areas. It effectively avoids the problems of edge paint accumulation, uneven thickness of main coating, and edge defects that are easy to occur in traditional single-nozzle spraying, and greatly improves the overall coating forming quality of complex curved surface workpieces. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0031] Figure 2 This is an enlarged schematic diagram of the shell structure of the present invention;

[0032] Figure 3 This is an enlarged schematic diagram of the multi-axis flexible robotic arm structure of the present invention;

[0033] Figure 4 This is an enlarged schematic diagram of the conveyor belt structure of the present invention.

[0034] The reference numerals in the figure are as follows: 1. Housing; 2. Multi-axis flexible robotic arm; 201. Upper arm base; 202. Upper arm pivot; 203. Spray head; 204. Intermediate connecting arm; 205. Support; 206. Base; 207. Support seat; 3. Conveyor belt; 301. Belt; 302. Chain; 303. Bracket; 304. Motor; 305. Position sensor; 306. Tensioning device. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] like Figures 1-4 As shown, an automatic nano-coating spraying device adapted to complex curved surfaces includes: a housing 1, a multi-axis flexible robotic arm 2, an adaptive attitude adjustment mechanism, a zoned atomizing nozzle group, an online laser thickness sensor, a closed-loop feedback control module, a flow precision control valve body, a conveyor belt 3, and a system control unit.

[0037] The housing 1 forms a closed spraying working chamber, and the conveyor belt 3 is arranged inside the housing 1 for workpiece transportation and station positioning.

[0038] A multi-axis flexible robotic arm 2 is mounted on one side of the housing 1. A spray head 203 is installed at the end of the multi-axis flexible robotic arm 2 via an adaptive attitude adjustment mechanism. A partitioned atomizing nozzle group and an online laser thickness sensor are mounted on the spray head 203. The online laser thickness sensor is electrically connected to a closed-loop feedback control module. The closed-loop feedback control module is electrically connected to a flow precision control valve body and a system control unit, respectively. The flow precision control valve body is connected to the paint feed end of the partitioned atomizing nozzle group.

[0039] The system control unit is electrically connected to the multi-axis flexible robotic arm 2, the conveyor belt 3, and the partitioned atomizing nozzle group, respectively.

[0040] In specific implementation, the shell 1 is the core protection and working cavity structure of the device. The whole is formed by closed sheet metal welding, which encloses and forms an independent and sealed spraying working cavity. It can effectively isolate the nano coating dust and atomized exhaust gas generated during the spraying process, prevent pollutants from overflowing, and at the same time isolate external dust and impurities from entering the spraying area, avoid particles and defects after the nano coating is sprayed, ensure a clean environment for spraying complex curved workpieces, improve the coating forming quality, and at the same time provide installation support and protection for various internal working parts.

[0041] The multi-axis flexible robotic arm 2 serves as the motion carrier for spraying, possessing multi-dimensional flexible adjustment capabilities. It overcomes the motion limitations of traditional rigid robotic arms, adapting to the contour trajectories of various irregular and complex curved workpieces. It drives the end-effector spray head 203 to complete omnidirectional, dead-angle-free spraying operations, solving the problem of incomplete spraying at concave, convex, and bent positions on complex curved surfaces. An adaptive attitude adjustment mechanism, mounted as the transition adjustment component between the multi-axis flexible robotic arm 2 and the spray head 203, can dynamically fine-tune the pitch, yaw, and tilt attitude of the spray head 203 in real time according to the curvature and angle changes of the complex curved surface of the workpiece. This ensures that the spray head always maintains the optimal vertical spraying angle and constant spraying distance with the workpiece surface to be sprayed, eliminating problems such as uneven spray thickness, missed spraying, and incomplete spraying at different positions on the curved surface. The zoned atomizing spray head assembly is a dedicated spraying execution component for nano-coatings. Adopting a zoned atomizing spraying structure, it can achieve fine atomization output of the coating, enabling differentiated spraying for different areas of the workpiece's curved surface, adapting to holes, etc. To meet the coating requirements of special structures such as edges and concave-convex surfaces, and to improve the adhesion and uniformity of nano-coatings, an online laser thickness sensor is used as a real-time thickness detection component. It has non-contact, high-precision detection capabilities and can collect thickness data simultaneously with the coating operation without stopping the machine. This achieves integrated coating and detection operations with nanometer-level accuracy, matching the ultra-thin coating requirements of nano-coatings. The closed-loop feedback control module is the core component of the device's intelligent control. It undertakes the closed-loop control functions of data reception, comparison and analysis, and command output. It can connect to the detection data and preset standard parameters, automatically identify coating thickness deviations, and output precise control signals, forming a closed-loop operation logic of detection, comparison, control, and correction to ensure the stability of coating accuracy. The flow precision control valve body is a component for precise control of the paint supply. It connects to the feed end of the zoned atomizing nozzle group and can finely adjust the paint supply flow and pressure in real time according to the control command. It can accurately match the paint spraying demand of different curved areas and avoid paint waste, paint accumulation, or thin coatings.

[0042] Conveyor belt 3 is an automated workpiece conveying and positioning component, undertaking the functions of workpiece loading, station conveying, and precise positioning. It can realize continuous workpiece feeding and, together with the system control unit, complete the precise alignment of the spraying station, ensuring the consistency and continuity of batch workpiece spraying. The system control unit is the core component of the device's overall control, coordinating the operation logic of all electrical and mechanical components, and centrally controlling the entire process of workpiece conveying, robotic arm trajectory movement, nozzle spraying, thickness detection, flow regulation, etc., to realize automated, intelligent, and unmanned spraying operations.

[0043] As a technical optimization of the present invention, the multi-axis flexible robotic arm 2 includes:

[0044] Support base 207 is fixedly installed on one side of conveyor belt 3;

[0045] The base 206 is fixedly mounted on the support 207;

[0046] Support 205 is mounted on base 206 and can rotate about the vertical axis of base 206;

[0047] The intermediate connecting arm 204 is hinged to the support 205 and can make pitching motion around the horizontal axis of the support 205.

[0048] The upper arm seat 201 is hinged to the upper end of the intermediate connecting arm 204, and can make the intermediate connecting arm 204 pitch or swing.

[0049] The upper arm pivot 202 is installed at the front end of the upper arm seat 201 and can rotate the upper arm seat 201 axially.

[0050] The spray head 203 is fixed to the end of the upper arm pivot 202;

[0051] This creates a motion chain with at least five degrees of freedom, enabling the spray head 203 to adjust its position and angle relative to the workpiece surface in real time.

[0052] In specific implementation, the support base 207 is the bottom fixed support component of the multi-axis flexible robotic arm 2. It is made of high-strength steel structure material and is fixedly installed on one side of the housing 1. It has high stability and high load-bearing capacity, which can offset the vibration during the movement of the robotic arm, avoid the operation deviation, and ensure the installation accuracy and operation stability of the overall mechanical structure. The base 206 is fixedly assembled on the bearing base at the upper end of the support base 207, providing a fixed installation benchmark for the upper rotating and hinged structure. It has high positioning accuracy, which can limit the bottom displacement of the multi-axis flexible robotic arm 2, and ensure that all moving parts of the upper part move accurately based on the benchmark position, eliminating the spraying trajectory error caused by benchmark deviation. The support 205 is mounted on the rotating base component above the base 206, and has a built-in vertical rotation drive motor and precision bearing structure. It can achieve 360° vertical axis rotation, providing power for the overall horizontal steering adjustment of the multi-axis flexible robotic arm 2, and adapting to the spraying needs of different positions on the left and right and circumferential surfaces of the workpiece. The middle connecting arm 204 is the core transmission and swing component in the middle section of the multi-axis flexible robotic arm 2. It is connected to the support 205 through a hinge structure and can swing up and down around the horizontal axis to achieve a wide range of adjustment of the height of the spray head 203, adapting to spraying scenarios with workpiece height differences and surface curvature changes. The upper arm seat 201 is the upper hinge bearing component of the multi-axis flexible robotic arm 2. It can perform multi-angle pitch and swing composite motion relative to the middle connecting arm 204, further enriching the motion dimensions of the multi-axis flexible robotic arm 2, reducing spraying dead angles, and accurately adapting to the spraying trajectory of the workpiece's fine curved surface and bent structure.

[0053] The upper arm pivot 202 is a precision rotating component at the front end, capable of 360° axial rotation. This drives the end spray head 203 to perform angle fine-tuning, precisely matching the tilt angle of complex curved surfaces. This ensures that the spray head's spraying posture always adheres to the workpiece surface. The spray head 203 is the terminal component that directly performs the nano-coating spraying operation. It integrates a zoned atomizing nozzle group and a sensor mounting position. Relying on a multi-degree-of-freedom kinematic chain, it can achieve precise positioning and spraying at any position and angle in space, perfectly adapting to the spraying process requirements of various complex curved workpieces. The five-degree-of-freedom kinematic chain is formed by a combination of multi-dimensional motion structures such as vertical rotation, horizontal pitch, upper arm swing, and axial rotation. This breaks through the motion limitations of traditional three-axis robotic arms and has the ability to flexibly adjust in all directions in space. It is the core mechanical foundation for the device to adapt to complex curved surface spraying.

[0054] As a technical optimization of the present invention, the partitioned atomizing nozzle group includes a central area nozzle and an edge area nozzle. The system control unit controls the opening and closing of the central area nozzle and the spray width of the edge area nozzle individually or in combination according to the shape of the edge, hole or ridge of the workpiece surface.

[0055] In practice, the central nozzle is the core main spray nozzle of the partitioned atomizing nozzle group. It has a large spray width, high coating atomization uniformity, and stable spray flow. It is mainly suitable for nano-coating operations on flat curved surfaces and large main areas of workpieces. It can quickly complete uniform spraying of large areas and ensure the consistency of the main coating thickness. The edge nozzle is the auxiliary precision spray nozzle of the partitioned atomizing nozzle group. It has a fine spray width, small adjustable range, and high positioning accuracy. It is specially designed for narrow and special structural areas such as workpiece edges, ridges, inner walls of holes, and curved corners. It can avoid the problems of edge overflow, accumulation, and missed spraying when spraying with large-width nozzles. The partitioned independent control logic allows the system control unit to identify the structural characteristics of the workpiece through preset programs and open or close the central nozzle or edge nozzle for different areas. It can also combine two nozzles for collaborative operation. At the same time, it can dynamically adjust the spray width and atomization intensity of each nozzle to achieve differentiated spraying modes for efficient spraying of large main areas and precise touch-up spraying of special areas, which greatly improves the overall spraying quality of complex curved workpieces.

[0056] As a technical optimization of the present invention, the online laser thickness sensor is fixedly mounted on the side wall of the spray head 203 and moves synchronously with the spray head 203. The online laser thickness sensor collects the coating thickness data of the sprayed workpiece in real time and transmits it to the closed-loop feedback control module.

[0057] In practical implementation, the online laser thickness sensor adopts the high-precision laser interferometry detection principle. It is a non-contact detection device specifically designed for nano-coatings, with detection accuracy reaching the nanometer level. It is suitable for the thickness detection needs of ultra-thin nano-coatings, without detection contact damage, and will not damage the uncured sprayed coating. The synchronous moving installation structure is fixed to the side wall of the spray head 203 and is integrated with the spraying terminal. It can move synchronously with the movement trajectory of the spray head 203, realizing real-time follow detection wherever the spraying is, with no detection blind spots. It can fully cover all complex curved surface spraying areas of the workpiece. The real-time data transmission function allows the sensor to continuously collect real-time coating thickness data at each spraying point during operation and transmit it synchronously to the closed-loop feedback control module in real time via electrical signals. No manual sampling or machine stoppage is required, realizing dynamic monitoring of the spraying process and providing accurate data support for subsequent thickness deviation correction and parameter adjustment.

[0058] As a technical optimization of the present invention, the flow precision control valve body is a miniature electromagnetic flow valve. The closed-loop feedback control module outputs a control signal based on the difference between the measured coating thickness and the preset standard thickness. The flow precision control valve body adjusts the coating supply flow of the partitioned atomizing nozzle group in real time, and synchronously corrects the moving speed of the multi-axis flexible robotic arm 2 and the atomizing air pressure of the nozzle.

[0059] In practical implementation, the miniature electromagnetic flow valve adopts an electromagnetically driven precision adjustment structure, which has a fast response speed and high flow regulation accuracy. It can achieve stepless fine adjustment of micro-flow, perfectly adapting to the micro-volume and uniform spraying requirements of nano-coatings. It can accurately control the instantaneous supply of nano-coatings, eliminating coating thickness deviations caused by flow fluctuations. The thickness difference comparison and control logic is a data comparison algorithm built into the closed-loop feedback control module. It can automatically compare the measured coating thickness collected by the sensor with the system's preset standard thickness threshold, accurately calculate the thickness deviation value, and output an electronic control signal of corresponding strength according to the magnitude of the deviation, achieving precise matching control. Multi-parameter synchronous linkage correction means that the device has integrated linkage control capability, not just adjusting the coating flow rate. It can synchronously and linkagely correct the moving speed of the multi-axis flexible robotic arm 2 and the atomizing air pressure of the zoned atomizing nozzle group according to the coating thickness deviation. When the coating is too thin, the coating flow rate is increased, the robotic arm moving speed is reduced, and the atomizing air pressure is increased. When the coating is too thick, the coating flow rate is reduced, the moving speed is increased, and the atomizing air pressure is finely adjusted. Multi-dimensional collaboration ensures that the coating thickness is uniform and meets the standard.

[0060] As a technical optimization of the present invention, the conveyor belt 3 includes a belt 301, a chain 302, a bracket 303, a drive motor 304, a positioning sensor 305, and a tensioning device 306.

[0061] The bracket 303 is fixed to the bottom of the housing 1. The belt 301 and the chain 302 are linked and arranged on the bracket 303. The output end of the drive motor 304 is connected to the belt 301 through the chain 302. The position sensor 305 is mounted at the spraying station of the bracket 303. The tensioning device 306 is installed on the side of the bracket 303. The position sensor 305 is used to detect whether the workpiece has reached the spraying station and transmit the position signal to the system control unit.

[0062] In specific implementation, belt 301 is the workpiece bearing and conveying surface of conveyor belt 3. It is made of anti-slip, wear-resistant, and solvent-resistant material to avoid corrosion and damage from the sprayed paint, while preventing slippage and deviation during workpiece conveying, ensuring the smoothness of workpiece conveying, and adapting to the bearing requirements of various specifications of workpieces. Chain 302 is the power transmission component of conveyor belt 3, linked with drive motor 304. It has high transmission accuracy, strong load-bearing capacity, and good running stability, and can accurately transmit power to ensure that belt 301 runs at a uniform speed and synchronously, avoiding workpiece spraying position deviation caused by fluctuations in conveying speed. Bracket 303 is the overall support frame structure of conveyor belt 3, made of high-strength rust-proof steel, fixed to the bottom of housing 1, providing a stable mounting base for belt, chain, drive component, and sensing component. The structure is stable and can withstand workpiece loads for a long time without deformation. Drive motor 304 is the power transmission component of conveyor belt 3. The power source component uses an adjustable speed servo motor, which can receive commands from the system control unit to precisely control the start and stop of the conveyor and the conveying speed. It is suitable for different operation modes such as continuous spraying of batch workpieces and precise positioning spraying of single workpieces. The positioning sensor 305 uses an infrared or photoelectric sensor, which is installed at the precision spraying station. It can sense the positioning status of the workpiece in real time and accurately identify whether the workpiece has entered the designated spraying area. After the workpiece is in position, it immediately transmits a signal to the system control unit. The system automatically triggers the linkage action of starting the robotic arm to spray and pausing the conveyor belt for positioning, so as to achieve precise positioning of the station. The tensioning device 306 is the tension adjustment component of the conveyor belt 3. It can adjust the tension of the chain 302 and the belt 301 in real time, compensate for the slack deformation caused by long-term operation, prevent conveying jams, deviations, and slippage, ensure the long-term stable and precise operation of the conveyor belt 3, and improve the positioning accuracy of the workpiece.

[0063] As a technical optimization of the present invention, the system control unit adopts an embedded microprocessor, and the system control unit integrates and stores preset spraying parameters and standard coating thickness thresholds.

[0064] In practical implementation, the embedded microprocessor serves as the core computing and control chip of the system control unit. It features high computing speed, high stability, strong anti-interference capability, and adaptability to complex industrial spraying conditions. It can simultaneously process multi-channel sensor signals, motion control signals, and flow regulation signals to achieve precise control of multiple components in a coordinated manner, meeting the real-time computing needs of automated spraying. The preset spraying parameter storage function is an integrated storage module within the unit, which can pre-enter and store exclusive spraying parameters for workpieces with different materials and curved surface structures, including process parameters such as spraying trajectory, robotic arm movement speed, nozzle spray width, paint flow rate, and atomization pressure. It can realize one-click recall of parameters for different workpieces, adapting to the spraying production of multiple types of workpieces. The standard coating thickness threshold storage function has multiple built-in standard nano-coating thickness thresholds, which can correspond to the spraying process requirements of different workpieces. It provides a precise benchmark for thickness comparison and deviation correction of the closed-loop feedback control module, ensuring that the nano-coating thickness of all workpieces after spraying meets the process standards, and ensuring product spraying consistency and pass rate.

[0065] Working principle:

[0066] First, the workpiece to be sprayed is conveyed into the sealed spraying working chamber formed by the housing 1 through the belt 301 and chain 302 of the conveyor belt 3. The drive motor 304 drives the chain 302 to move according to the instructions of the system control unit. When the workpiece reaches the spraying station on the support 303, the position sensor 305 detects the workpiece and transmits the position signal to the system control unit. The system control unit then controls the conveyor belt 3 to pause and position and starts the multi-axis flexible robotic arm 2. The support seat 207, base 206, support 205, intermediate connecting arm 204, upper arm seat 201 and upper arm rotating shaft 202 of the multi-axis flexible robotic arm 2 constitute a kinematic chain with at least five degrees of freedom. The system control unit drives the joints to move according to the preset spraying trajectory, so that the spraying head 203 reaches the starting spraying position on the workpiece surface. At the same time, the pitch and deflection angle of the spraying head 203 are adjusted in real time through the adaptive attitude adjustment mechanism to ensure that the central area nozzle and the edge area nozzle of the partitioned atomizing nozzle group maintain the best vertical distance and angle with the complex curved surface of the workpiece.

[0067] Secondly, the system control unit controls the opening and closing of the central and edge nozzles and the spray width of the zoned atomizing nozzle group individually or in combination, based on the shape of the workpiece surface's edges, holes, or ridges. Simultaneously, it activates the flow precision control valve to supply the nano-coating. An online laser thickness sensor is fixedly mounted on the side wall of the spray head 203 and moves synchronously with it, collecting real-time coating thickness data of the sprayed area and transmitting it to the closed-loop feedback control module. The closed-loop feedback control module compares the measured thickness with the preset standard coating thickness threshold in the system control unit, outputs a control signal based on the difference, and adjusts the coating supply flow of the zoned atomizing nozzle group in real-time through the flow precision control valve. It also synchronously corrects the movement speed of the multi-axis flexible robotic arm 2 and the nozzle atomizing air pressure, achieving closed-loop control with simultaneous spraying and measurement, and real-time correction.

[0068] Finally, during the spraying process, the multi-axis flexible robotic arm 2 drives the spraying head 203 to spray all complex curved areas of the workpiece according to the planned trajectory. The zoned atomizing nozzle group dynamically switches the operation mode of the central area nozzle and the edge area nozzle according to the regional characteristics. The main body area is sprayed with the central area nozzle for efficient and uniform spraying, while the edge area nozzle is used for fine touch-up spraying of the edges, edges, holes and other areas. At the same time, the online laser thickness sensor continuously monitors the coating thickness at each point. The closed-loop feedback control module continuously fine-tunes the flow rate to accurately control the movement parameters of the valve body and the multi-axis flexible robotic arm 2 until the entire workpiece is sprayed. After the spraying is completed, the system control unit controls the drive motor 304 of the conveyor belt 3 to restart and send the sprayed workpiece out of the housing 1. At the same time, the tensioning device 306 maintains the appropriate tension of the chain 302 and the belt 301 to ensure that the next workpiece is accurately positioned and enters the spraying station, thus achieving continuous automated operation.

[0069] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. An automatic nano-coating spraying device adaptable to complex curved surfaces, characterized in that, include: The system comprises: housing (1), multi-axis flexible robotic arm (2), adaptive attitude adjustment mechanism, zoned atomizing nozzle group, online laser thickness sensor, closed-loop feedback control module, flow precision control valve body, conveyor belt (3), and system control unit. The housing (1) forms a closed spraying working chamber, and the conveyor belt (3) is arranged inside the housing (1) for workpiece transportation and station positioning. The multi-axis flexible robotic arm (2) is mounted on one side of the housing (1). The end of the multi-axis flexible robotic arm (2) is equipped with a spray head (203) through the adaptive attitude adjustment mechanism. The partitioned atomizing spray head group and the online laser thickness sensor are mounted on the spray head (203). The online laser thickness sensor is electrically connected to the closed-loop feedback control module. The closed-loop feedback control module is electrically connected to the flow precision control valve body and the system control unit respectively. The flow precision control valve body is connected to the paint feed end of the partitioned atomizing spray head group. The system control unit is electrically connected to the multi-axis flexible robotic arm (2), the conveyor belt (3), and the partitioned atomizing nozzle group, respectively.

2. The automatic nano-coating spraying device adaptable to complex curved surfaces according to claim 1, characterized in that, The multi-axis flexible robotic arm (2) includes: Support base (207) is fixedly installed on one side of the conveyor belt (3); The base (206) is fixedly mounted on the support (207); The support (205) is mounted on the base (206) and can rotate about the vertical axis of the base (206); The intermediate connecting arm (204) is hinged to the support (205) and can pitch around the horizontal axis of the support (205); The upper arm seat (201) is hinged to the upper end of the intermediate connecting arm (204) and can perform pitching or swinging movements of the intermediate connecting arm (204); The upper arm pivot (202) is installed at the front end of the upper arm seat (201) and can rotate the upper arm seat (201) axially. The spray head (203) is fixed to the end of the upper arm pivot (202); This forms a motion chain with at least five degrees of freedom, enabling the spray head (203) to adjust its position and angle relative to the workpiece surface in real time.

3. The automatic nano-coating spraying device adaptable to complex curved surfaces according to claim 1, characterized in that, The partitioned atomizing nozzle group includes a central area nozzle and an edge area nozzle. The system control unit controls the opening and closing of the central area nozzle and the spray width of the edge area nozzle individually or in combination, according to the shape of the edge, hole or ridge of the workpiece surface.

4. The automatic nano-coating spraying device adaptable to complex curved surfaces according to claim 1, characterized in that, The online laser thickness sensor is fixed to the side wall of the spray head (203) and moves synchronously with the spray head (203). The online laser thickness sensor collects the coating thickness data of the sprayed workpiece in real time and transmits it to the closed-loop feedback control module.

5. The automatic nano-coating spraying device adaptable to complex curved surfaces according to claim 1, characterized in that, The flow precision control valve body is a miniature electromagnetic flow valve. The closed-loop feedback control module outputs a control signal based on the difference between the measured coating thickness and the preset standard thickness. The flow precision control valve body adjusts the coating supply flow of the partitioned atomizing nozzle group in real time, and synchronously corrects the moving speed of the multi-axis flexible robotic arm (2) and the atomizing air pressure of the nozzle.

6. The automatic nano-coating spraying device adaptable to complex curved surfaces according to claim 1, characterized in that, The conveyor belt (3) includes a belt (301), a chain (302), a bracket (303), a drive motor (304), a position sensor (305), and a tensioning device (306). The bracket (303) is fixed to the bottom of the housing (1). The belt (301) and the chain (302) are linked and arranged on the bracket (303). The output end of the drive motor (304) is connected to the belt (301) through the chain (302). The position sensor (305) is mounted at the spraying station of the bracket (303). The tensioning device (306) is installed on the side of the bracket (303). The position sensor (305) is used to detect whether the workpiece has reached the spraying station and transmit the position signal to the system control unit.

7. The automatic nano-coating spraying device adaptable to complex curved surfaces according to claim 1, characterized in that, The system control unit uses an embedded microprocessor, and integrates and stores preset spraying parameters and standard coating thickness thresholds.

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