Robot coating system and method for spraying paint character marks on surfaces of cylinders

Abstract

The robot coating system and method for spraying the paint character marks on the surfaces of the cylindrical products mainly comprise a tool table (1) and a tool clamp (4), the tool clamp (4) is installed on the tool table (1), and the robot coating system is characterized by further comprising a collaborative robot (2), a spraying actuator (3), an ultrasonic cleaning instrument (19), an air pump (20) and a control cabinet (6); the spraying actuator (3) is mounted at the tail end of the collaborative robot (2); the collaborative robot (2) and the ultrasonic cleaning instrument (19) are connected with the control cabinet (6) through cables, and the spraying actuator (3) is provided with a piezoelectric valve controller. The air pump (20) is connected with the spraying actuator (3) through the pressure regulating valve and provides stable pressure for paint. A new solution is provided for paint material mark spraying operation, the spraying operation efficiency is improved, and meanwhile the influence of paint on the body of a worker is reduced.

Description

Technical Field

[0001] The invention belongs to the field of automatic spraying, and in particular relates to a robot coating system for spraying paint-type character markings on the surface of a barrel product. Background Art

[0002] In my country's manufacturing industry, especially in the manufacturing and assembly of products in the fields of aviation, aerospace, automobiles, etc., there are a large number of cylindrical workpieces, which need to be marked with characters and painted before leaving the factory. This process is very harmful to the human body and is characterized by high flexibility and high pollution.

[0003] Some existing automatic spraying equipment can only process low-viscosity, low-volatile materials such as ink and printing ink, and cannot perform customized marking coatings on cylindrical workpieces.

[0004] Currently, the paint coating of cylindrical workpieces is basically completed by manually operating spray guns and molds. Usually, two operators work together to first isolate the coating area with tape, and then one operator holds the mold and the other operator holds the spray gun to complete the coating of specific logos. Due to the large output of a single batch of products, the task of mold production and isolation of the coating area is large and time-consuming. On the other hand, when working manually, the spray gun operating distance and the spray gun moving speed have a direct impact on the paint diffusion degree and paint thickness of the painted logo, and it is impossible to guarantee the consistency of coating quality and product appearance quality. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention proposes a robot coating system for spraying paint-type character markings on the surface of cylindrical products. Through the precise control of the robot speed, trajectory, piezoelectric valve parameters and pressure, the defects of the traditional operation method such as inefficiency and unstable quality are improved, the intelligence and automation of the coating of cylindrical product markings are improved, and cylindrical product markings with stable quality and controllable process are obtained.

[0006] A robot coating system for spraying paint character markings on the surface of cylindrical products mainly includes a workbench 1 and a work fixture 4, wherein the work fixture 4 is installed on the workbench 1. It is characterized in that it also includes a collaborative robot 2, a spray actuator 3, an ultrasonic cleaner 19, an air pump 20 and a control cabinet 6, wherein the spray actuator 3 is installed on the end of the collaborative robot 2; the collaborative robot 2 and the ultrasonic cleaner 19 are connected to the control cabinet 6 via cables, wherein the spray actuator 3 is provided with a piezoelectric valve controller; the air pump 20 is connected to the spray actuator 3 via a pressure regulating valve to provide stable pressure for the paint.

[0007] The piezoelectric valve 8 is installed on the end flange of the collaborative robot 2 through a piezoelectric valve adapter 21. A high-frequency vibrating piezoelectric ceramic piece is provided inside the piezoelectric valve 8. A flow channel heater 12 is connected to the lower end of the piezoelectric valve 8. The flow channel heater 12 is also connected to the piezoelectric valve flow channel 11 on one end of the upper surface. The Luer connector 24 at the lower end of the barrel 2 is connected to the upper end of the piezoelectric valve flow channel 11.

[0008] The piezoelectric valve 8 is provided with a power line 14, a control signal line 13 and a heating control line 16, which are connected to the control cabinet 6 through the collaborative robot 2; the air pump 20 is connected to the tail of the barrel 22 and the piezoelectric valve cooling air channel 15 through pipelines, respectively, to fill the barrel 22 and the piezoelectric valve cooling air channel 15 with compressed air; a piezoelectric valve adapter 21 is provided on the side of the piezoelectric valve 8, and the piezoelectric valve 8 is connected to the end flange of the collaborative robot 2 through the piezoelectric valve adapter 21;

[0009] The fixture 4 includes a supporting block 17 and a positioning block 18 . The product object 5 is provided with a plug connection hole 23 . When working, the plug connection hole 23 of the product object 5 is sleeved on the positioning block 18 .

[0010] It has the functions of automatic recognition and encoding of characters and logos, and can automatically generate or call the collaborative robot's motion trajectory from the database, and cooperate with the spray actuator 3 control instructions added to the motion trajectory of the system to achieve the purpose of automatic coating of paint characters and logos.

[0011] The robot coating method for spraying paint character markings on the surface of a cylindrical product is characterized in that the robot coating system for spraying paint character markings on the surface of a cylindrical product according to claim 1 is used to spray paint character markings, including three processes of manual pre-coating preparation, automatic execution of coating instructions by the system, and subsequent coating work, and the specific steps include:

[0012] Manual preparation before coating:

[0013] Step 1: The operator installs the flow channel 11, nozzle 9, and plug 10 that were disassembled and cleaned after the previous shift coating work on the striker of the piezoelectric valve 8, and installs the piezoelectric valve 8 on the adapter 21 connected to the robot flange. Then, the operator installs the flow channel heater 12 under the flow channel 11 and completes the connection of the power line 14, control signal line 13, and heater control line 16.

[0014] Step 2: While the hardware of the present invention is being installed, the paint viscosity is adjusted to within the threshold range allowed for coating work using the original paint and thinner in the batching room, and loaded into the barrel 25, which is installed on the piezoelectric valve Luer connector 24, completing the preliminary preparations for marking coating.

[0015] Step 3: Next, the operator fixes the cylindrical part 5 on the workpiece fixture 4 by hand or with the help of a truss, and uses the fixture positioning block 18 and the surface features of the workpiece (the drop-off plug connection hole 23) to perform axial and angular positioning of the workpiece.

[0016] Step 4: After the fixture positioning is completed, the workpiece coordinate system of the actual cylindrical product is consistent with the workpiece coordinate system calibrated in advance.

[0017] The system automatically executes coating instructions:

[0018] Step 1: After the tube product 5 is fixedly installed, the operator enters the product identification, coating area and other information of the current batch in the interactive interface 7;

[0019] Step 2: The program automatically generates a QR code matrix containing the corresponding identification information and executes the coating instruction. The specific upper computer software execution logic is as follows: Figure 4 shown.

[0020] Step 3: The host computer software deconstructs the input character identifier, compares it with the spray character database, and calls the corresponding character trajectory in sequence according to the index value of the current input number.

[0021] Step 4: At the same time, the software adjusts the spraying starting point online according to the coating area input by the operator, and the spraying starting point remains consistent with the set position.

[0022] Step 5: During the coating process, the software updates the workpiece coordinate system of the currently running character subroutine in real time according to the coating order and coating area, that is, updates the current motion trajectory of the robot. The robot motion trajectory corresponding to each character in the database has the control signal of the piezoelectric valve inserted between the points. After being called by the main program, the piezoelectric valve can be controlled in the specified area to cooperate with the robot movement to perform automatic label coating.

[0023] Step 6: During the marking coating process, the host computer software solves the generated two-dimensional code matrix, uses the Boolean value in the two-dimensional matrix to rewrite the piezoelectric valve control signal on the predetermined spraying trajectory, and automatically performs the coating of the two-dimensional code dot matrix after the marking spraying work is completed.

[0024] Post-coating work:

[0025] Step 7. After the single-shot product label coating is completed, the operator transfers the product to the factory logistics system.

[0026] Step 8. Measure the viscosity of the paint every 4 working hours. If the viscosity value is out of tolerance, it needs to be replenished or re-mixed.

[0027] Step 9. After a single shift of coating work is completed, the operator needs to remove the piezoelectric valve 8 and use an ultrasonic cleaner 19 to clean the flow channel 11, nozzle 9, plug 10 and other easily contaminated parts, and reinstall them after the next shift starts.

[0028] The invention is beneficial in that:

[0029] 1. The present invention provides a new solution for the marking spraying of paint materials, improves the efficiency of the spraying operation, and reduces the impact of paint on the health of workers;

[0030] 2. The present invention forms an automatic coating system through character and logo recognition and robot trajectory planning technology, and realizes automatic coating of complex characters and logos of paint materials, such as QR codes, on curved surfaces; BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is the overall layout diagram of the coating system of the present invention;

[0032] Figure 2 This is a schematic diagram of the spray actuator of the present invention;

[0033] Figure 3 A schematic diagram of the state of the fixture clamping a product when the present invention is working;

[0034] Figure 4 This is a product identification spraying control flow chart of the present invention.

[0035] Explanation of the marks in the accompanying drawings: 1 is a workbench; 2 is a collaborative robot; 3 is an actuator; 4 is a work fixture; 5 is the actual product; 6 is a control cabinet; 7 is an interactive touch screen; 8 is a piezoelectric valve body; 9 is a nozzle; 10 is a plug; 11 is a flow channel; 12 is a flow channel heater; 13 is a control signal line; 14 is a power line; 15 is a cooling air channel; 16 is a heater control line; 17 is a fixture support block; 18 is a fixture positioning block; 19 is an ultrasonic cleaner; 20 is an air pump; 21 is a piezoelectric valve adapter; 22 is a barrel; 23 is a disconnect plug connection hole; 24 is a Luer connector. DETAILED DESCRIPTION

[0036] The main purpose of the present invention is to solve the problem that the existing technology cannot automatically apply the marking of high-viscosity materials such as paint on the cylindrical surface of a cylinder. Through robot offline programming, piezoelectric injection valve, and trajectory update algorithm, the task of spraying the marking of cylinder products can be fully automated.

[0037] In order to achieve the above purpose, the technical scheme adopted by the present invention is as follows:

[0038] A robot coating system for spraying paint-type character identification on the surface of barrel products, including a collaborative robot, a piezoelectric valve, an air pump, an ultrasonic cleaning instrument, a workpiece fixture, and a host computer control software. The piezoelectric valve is installed at the end of the robot, including a piezoelectric ceramic drive sheet, a flow channel, a nozzle, a striker and other structures. The piezoelectric ceramic high-frequency vibration sprays the paint in the barrel from the nozzle in the form of droplets, and can spray high-viscosity, low-fluidity materials such as glue and paint on the surface of the product in a printing manner to form target characters. The actuator mounting frame is installed at the end of the collaborative robot. The air pump is installed at the outer edge of the workbench to provide stable air pressure for the piezoelectric valve barrel to ensure uniform discharge. The work fixture is installed on the working plane of the workbench to install and fix barrel products. The host computer control software includes a communication interface, a trajectory update algorithm, and a UI interface, which can realize the function of automatically coating the surface of barrel products according to the character identification, identification and other contents input by the operator. The ultrasonic cleaning instrument is used for cleaning components that are easily contaminated, such as piezoelectric valve flow channels and nozzles.

[0039] The present invention proposes a robot coating system for spraying paint character identification on the surface of a tube product. When the present invention is working, the pre-coating preparation work is first performed. The flow channel, nozzle, and sealing bolt that are disassembled and cleaned after the previous shift coating work are installed at the piezoelectric valve striker, and the piezoelectric valve is installed on the robot end mounting part. In the batching room, the viscosity of the paint is adjusted to the threshold range allowed by the coating work with the original paint and thinner, and the barrel is loaded, and the barrel is installed on the piezoelectric valve Luer joint to complete the pre-coating work of the identification. Then, the operator fixes the tube parts on the workpiece fixture by hand or with the help of a truss, and uses the fixture and the surface features of the workpiece to perform axial and angular positioning of the workpiece. At this time, the workpiece coordinate system of the actual tube product is consistent with the workpiece coordinate system calibrated in advance. After the tube parts are fixed and installed, the operator enters the product identification, coating area and other information of the current batch in the interactive interface, and the program automatically generates a two-dimensional code matrix containing the corresponding identification information, and executes the coating instruction. The upper computer software deconstructs the input character identification, compares it with the spray character database, and calls the corresponding character trajectory in sequence according to the index value of the current input number. At the same time, the software adjusts the origin of the workpiece coordinate system online according to the coating area input by the operator, and the spraying starting point is consistent with the set position. On this basis, the software will update the workpiece coordinate system of the currently running character subroutine in real time according to the coating order and coating area during the coating process, that is, update the current motion trajectory of the robot. The robot motion trajectory corresponding to each character in the database has the control signal of the piezoelectric valve inserted between the points. After being called by the main program, the piezoelectric valve can be controlled in the specified area to cooperate with the robot movement to perform automatic label coating. During the label coating process, the upper computer software solves the generated QR code matrix, uses the Boolean value in the two-dimensional matrix to rewrite the piezoelectric valve control signal on the predetermined spraying trajectory, and automatically coats the QR code dot matrix after the label spraying work is completed. After the label coating of a single product is completed, the operator transfers the product to the factory logistics system. The viscosity of the paint is measured every 4 working hours. If the viscosity value is out of tolerance, it needs to be replenished or redistributed. After a single shift of coating work is completed, the operator needs to remove the piezoelectric valve and use an ultrasonic cleaner to clean the flow channel, nozzle, plug and other easily contaminated parts, and then reinstall them when the next shift starts.

[0040] In order to better explain the technology of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0041] like Figure 1As shown, it is an overall diagram of the coating system of the present invention, including a workbench 1, on which a collaborative robot 2, a workpiece fixture 4, and an ultrasonic cleaner 19 are arranged, and a physical product 5 is placed on the workpiece fixture 4. The actuator 3 is installed at the end of the collaborative robot 2 and connected to the robot flange through an adapter 21. An air pump 20 is placed on one side of the workbench to fill the barrel 22 and the piezoelectric valve cooling air channel 15 with compressed air, and a control cabinet 6 is placed on the other side of the workbench. A human-machine interactive touch screen 7 is provided on the front of the control cabinet 6 to facilitate the operator to run the coating program through the touch screen.

[0042] like Figure 2 As shown, it is a model diagram of the spray actuator. The actuator body is a piezoelectric valve 8, which is installed on the end flange of the robot through a piezoelectric valve adapter 21. The piezoelectric valve is vibrated by a piezoelectric ceramic piece encapsulated in the main structure 8 at a high frequency, and the paint in the flow channel 11 is pushed out from the nozzle 9 in the form of droplets by the striker, so as to obtain a high-frequency jet with stable flow rate and pressure. The barrel 25 is installed on the piezoelectric valve flow channel through the threaded structure of the Luer connector 24, and the compressed air provided by the air pump continuously injects paint into the flow channel. The plug 10 is installed on the side of the flow channel through a threaded hole to prevent the paint from overflowing. At the same time, it is convenient to clean the flow channel after removing the plug 10. The flow channel heater 12 is used to heat the paint in the flow channel, which can control the viscosity, volatilization speed and curing speed of the paint. The piezoelectric valve is connected to a power line 14, a control signal line 13 and a heating control line 16. The connecting line is attached to the outside of the robot through XX and connected to the control cabinet.

[0043] Figure 3 As shown in the working fixture diagram of the present invention, the fixture body is divided into a support block 17 and a positioning block 18. The support block 17 includes a mounting structure and two cylindrical support structures, and is mounted on the workbench surface through the mounting structure. The product is placed on the cylindrical support structure. The positioning block 18 is installed on the cylindrical contact structure on the left side of the support block 17, and can cooperate with the product drop-off plug connection hole 23 to achieve axial and angular positioning of the product.

[0044] When the present invention works,

[0045] 1. Manually perform preparation work before coating.

[0046] (1) The operator installs the flow channel 11, nozzle 9, and plug 10 that were disassembled and cleaned after the previous shift's coating work on the striker of the piezoelectric valve 8, and installs the piezoelectric valve 8 on the adapter 21 connected to the robot flange. Then, the operator installs the flow channel heater 12 under the flow channel 11 and completes the connection of the power line 14, control signal line 13, and heater control line 16.

[0047] (2) While the hardware of the present invention is being installed, the paint viscosity is adjusted to within the threshold range allowed for coating work using the original paint and thinner in the batching room, and loaded into the barrel 25, which is then installed on the piezoelectric valve Luer connector 24, completing the preliminary preparations for marking coating.

[0048] (3) Next, the operator fixes the cylindrical part 5 to the workpiece fixture 4 by hand or with the aid of a truss, and uses the fixture positioning block 18 and the surface features of the workpiece (the drop-out plug connection hole 23) to perform axial and angular positioning of the workpiece.

[0049] (6) After the fixture positioning is completed, the workpiece coordinate system of the actual cylindrical product remains consistent with the workpiece coordinate system calibrated in advance.

[0050] 2. The system automatically executes coating instructions

[0051] (1) After the cylindrical product 5 is fixedly installed, the operator enters the product identification, coating area and other information of the current batch in the interactive interface 7;

[0052] (2) The program automatically generates a two-dimensional code matrix containing the corresponding identification information and executes the coating instruction. The specific upper computer software execution logic is as follows: Figure 4 shown.

[0053] (3) The host computer software deconstructs the input character identifier, compares it with the spray character database, and calls the corresponding character trajectory in sequence according to the index value of the current input number.

[0054] (4) At the same time, the software adjusts the spraying starting point online according to the coating area input by the operator, and the spraying starting point remains consistent with the set position.

[0055] (5) During the coating process, the software updates the workpiece coordinate system of the currently running character subroutine in real time according to the coating order and coating area, that is, updates the current motion trajectory of the robot. The robot motion trajectory corresponding to each character in the database has the control signal of the piezoelectric valve inserted between the points. After being called by the main program, the piezoelectric valve can be controlled in the specified area to cooperate with the robot movement to perform automatic label coating.

[0056] (6) During the marking coating process, the upper computer software solves the generated two-dimensional code matrix, uses the Boolean value in the two-dimensional matrix to rewrite the piezoelectric valve control signal on the predetermined spraying trajectory, and automatically performs the coating of the two-dimensional code dot matrix after the marking spraying work is completed.

[0057] 3. Subsequent work after coating

[0058] (1) After the single-shot product labeling is completed, the operator transfers the product to the factory logistics system.

[0059] (2) The viscosity of the paint should be measured every 4 working hours. If the viscosity value is out of tolerance, it needs to be replenished or re-mixed.

[0060] (3) After a single shift of coating work is completed, the operator needs to remove the piezoelectric valve 8 and use an ultrasonic cleaner 19 to clean the flow channel 11, nozzle 9, plug 10 and other easily contaminated parts, and then reinstall them after the next shift begins.

[0061] It is understandable that those skilled in the art can make equivalent substitutions or changes based on the technical solution and concept of the present invention, and all these changes or substitutions should fall within the protection scope of the claims attached to the present invention.

[0062] The present invention designs a robot automatic coating system for spraying paint character logos on the surface of barrel products. The system can automatically parse the character logo content according to user needs, control the robot to realize the automatic spraying of the logo, and is mainly used to solve the problem of spraying paint logos on the surface of barrel products. Due to the special material of paint, its fluidity is poor and the viscosity is high. Therefore, there is no mature equipment for automatically editing the spraying content of paint material on the market. The common automatic spray guns on the market can only be used for materials such as ink and printing ink. For the coating of paint logos, it is currently mainly dependent on manual operation using font auxiliary tools. The above work occupies more human resources, and the production of fonts is also time-consuming and laborious. At the same time, the benzene compounds in the paint play a role, which will cause harm to the health of the operator.

[0063] The system designed by the present invention mainly includes a collaborative robot, a piezoelectric valve, an air pump, an ultrasonic cleaning instrument, a workpiece fixture, and a host computer control software. When the present invention is working, the collaborative robot carries a piezoelectric valve as a spray actuator, and the air pump provides a stable pressure for the paint cylinder to keep the discharge amount and line width constant. The cylinder product is placed on the workpiece fixture, and the workpiece coordinate system is established based on the product feature point or outer contour. The present invention uses offline programming to directly obtain the robot movement point, and stores it in the robot controller. The IO signal is interspersed in the trajectory point to control the opening and closing of the piezoelectric valve, so as to perform a single character description and filling action. On this basis, the host computer software is developed to call a number of single-character motion instructions according to the character string input by the operator, and automatically update the graffiti position to complete the identification coating task. The piezoelectric valve used in the present invention has high requirements for the smooth flow of the flow channel. Therefore, after the coating system runs for 8 working hours, the operator removes the flow channel, nozzle, and sealing bolt at the end of the piezoelectric valve, and puts them into the ultrasonic cleaning instrument for cleaning. The invention improves the problem that the existing spraying equipment is difficult to handle the stable spraying of paints with high viscosity such as paints, and the production efficiency and the spraying quality are improved.

[0064] A robot coating system for spraying paint character marks on the surface of cylindrical products, which mainly includes a robot body, a robot controller, a robot offline programming software, a piezoelectric valve, an air pump, an ultrasonic cleaner, and a host computer control software. The robot carries a piezoelectric valve as an actuator of the coating system, and the robot offline programming software generates the robot lower computer motion program offline according to the edge features of various marks, and enters it into the robot controller.

[0065] The robot coating system for spraying paint character markings on the surface of cylindrical products is characterized in that the collaborative robot specifically includes: a robot body, a robot controller, and a robot offline programming software.

[0066] The robot coating system for spraying paint character marks on the surface of cylindrical products is characterized in that the piezoelectric valve specifically includes: a piezoelectric valve actuator, a piezoelectric valve controller, a syringe

[0067] The robot coating system for spraying paint character markings on the surface of cylindrical products is characterized in that the upper computer control software communicates with the robot controller through Ethernet, and at the same time receives the character content input by the operator through the interface, completes the character information analysis and updates the robot motion trajectory, and controls the robot to spray according to the character content.

Claims

1. A robot coating system for spraying paint-type character markings on the surface of a cylindrical product, mainly comprising a tooling table (1) and a tooling fixture (4), wherein the tooling fixture (4) is installed on the tooling table (1), and is characterized in that: It also includes a collaborative robot (2), a spray actuator (3), an ultrasonic cleaner (19), an air pump (20) and a control cabinet (6), wherein the spray actuator (3) is installed on the end of the collaborative robot (2); the collaborative robot (2) and the ultrasonic cleaner (19) are connected to the control cabinet (6) via cables, wherein the spray actuator (3) is provided with a piezoelectric valve controller; the air pump (20) is connected to the spray actuator (3) via a pressure regulating valve to provide stable pressure for the paint.

2. The robot coating system for spraying paint-type character markings on the surface of cylindrical products according to claim 1 is characterized in that: The piezoelectric valve (8) is installed on the end flange of the collaborative robot (2) through a piezoelectric valve adapter (21). A high-frequency vibrating piezoelectric ceramic sheet is provided inside the piezoelectric valve (8). The lower end of the piezoelectric valve (8) is connected to a flow channel heater (12). The flow channel heater (12) is also connected to the piezoelectric valve flow channel (11) on one end of the upper surface. The Luer connector 24 at the lower end of the barrel (2) is connected to the upper end of the piezoelectric valve flow channel (11).

3. The robot coating system for spraying paint-type character markings on the surface of cylindrical products according to claim 1 is characterized in that The piezoelectric valve (8) is provided with a power line (14), a control signal line (13) and a heating control line (16), and the power line (14), the control signal line (13) and the heating control line (16) are connected to the control cabinet (6) through the collaborative robot (2); the air pump (20) is connected to the tail of the barrel (22) and the piezoelectric valve cooling air duct (15) through pipelines, respectively, to fill the barrel (22) and the piezoelectric valve cooling air duct (15) with compressed air; a piezoelectric valve adapter (21) is provided on the side of the piezoelectric valve (8), and the piezoelectric valve (8) is connected to the end flange of the collaborative robot (2) through the piezoelectric valve adapter (21).

4. The robot coating system for spraying paint-type character markings on the surface of cylindrical products according to claim 2 is characterized in that: The fixture (4) comprises a supporting block (17) and a positioning block (18), and the product object (5) is provided with a detachable plug connection hole (23). During operation, the detachable plug connection hole (23) of the product object (5) is sleeved on the positioning block (18).

5. According to claim 1, the robot coating system for spraying paint-type character logos on the surface of cylindrical products has the function of automatic recognition and automatic encoding of characters and logos, and can automatically generate or call the motion trajectory of the collaborative robot from the database, and cooperate with the spray actuator (3) control instructions added to the motion trajectory of the system to achieve the purpose of automatic coating of paint-type characters and logos.

6. A robot coating method for spraying paint-type character markings on the surface of a cylindrical product, characterized in that: The robot coating system for spraying paint character markings on the surface of cylindrical products according to claim 1 is used to spray paint character markings, including three processes: manual pre-coating preparation, automatic execution of coating instructions by the system, and subsequent coating work. The specific steps include: Manual preparation before coating: Step 1: The operator installs the flow channel (11), nozzle (9), and plug (10) that have been disassembled and cleaned after the previous shift's coating work on the striker of the piezoelectric valve (8), and installs the piezoelectric valve (8) on the adapter (21) connected to the robot flange. Subsequently, the operator installs the flow channel heater (12) below the flow channel (11) and completes the connection of the power line (14), control signal line (13) and heater control line (16). Step 2: While the hardware of the present invention is being installed, the paint viscosity is adjusted to within the threshold range allowed for coating work using the original paint and the thinner in the batching room, and then loaded into the barrel (25), which is then installed on the piezoelectric valve Luer connector (24), completing the preliminary preparation work for marking coating. Step 3: Next, the operator fixes the cylindrical part (5) on the workpiece fixture (4) by hand or with the help of a truss, and uses the fixture positioning block (18) and the workpiece surface feature drop-out plug connection hole 23) to perform axial and angular positioning of the workpiece. Step 4: After the fixture positioning is completed, the workpiece coordinate system of the actual cylindrical product is consistent with the workpiece coordinate system calibrated in advance. The system automatically executes coating instructions: Step 1: After the cylindrical product (5) is fixedly installed, the operator enters the product identification, coating area and other information of the current batch in the interactive interface (7); Step 2: The program automatically generates a two-dimensional code matrix containing corresponding identification information and executes the coating instruction; Step 3: The host computer software deconstructs the input character identifier, compares it with the spray character database, and calls the corresponding character trajectory in sequence according to the index value of the current input number; Step 4: At the same time, the software adjusts the spraying starting point online according to the coating area input by the operator, and the spraying starting point is consistent with the set position; Step 5: During the coating process, the software updates the workpiece coordinate system of the currently running character subroutine in real time according to the coating order and coating area, that is, updates the current motion trajectory of the robot. The robot motion trajectory corresponding to each character in the database has the control signal of the piezoelectric valve inserted between the points. After being called by the main program, the piezoelectric valve can be controlled in the specified area to cooperate with the robot movement to perform automatic label coating; Step 6: During the marking coating process, the upper computer software solves the generated two-dimensional code matrix, uses the Boolean value in the two-dimensional matrix to rewrite the piezoelectric valve control signal on the predetermined spraying trajectory, and automatically performs the coating of the two-dimensional code dot matrix after the marking spraying work is completed; Post-coating work: Step 7: After the single-shot product label coating is completed, the operator transfers the product to the factory logistics system; Step 8: Measure the viscosity of the paint every 4 working hours. If the viscosity value is out of tolerance, it needs to be replenished or re-mixed; Step 9: After a single shift of coating work is completed, the operator needs to remove the piezoelectric valve (8) and use an ultrasonic cleaner (19) to clean the flow channel (11), nozzle (9), plug (10) and other easily contaminated parts, and reinstall them after the next shift begins.

Images