A fog-free coating equipment and a fog-free coating process

Abstract

This invention relates to a non-atomizing coating equipment, comprising a high-pressure feeding system, a coating robot, and a non-atomizing spraying device. The high-pressure feeding system includes an air booster pump, an air storage tank, a PLC control module, an air source control valve group connected to the PLC control module, several paint pressure storage tanks, a solvent storage tank, and a diaphragm pump. The non-atomizing spraying device is mounted on the actuator end of the coating robot via a clamp, and integrates a color-changing valve group, which includes a paint pneumatic valve, a solvent pneumatic valve, and a return pneumatic valve. This invention has the following advantages: 1. It can improve the spraying utilization rate, avoiding the problem of excessive paint overspraying on non-coating surfaces and saving production costs; 2. It eliminates atomization rebound, avoiding poor particulate paint mist, thus improving product qualification rate and reducing production costs; 3. The paint utilization rate is increased from below 40% in the traditional method to over 80%, thereby significantly reducing waste generation and making it more environmentally friendly.

Description

Technical Field

[0001] This invention relates to the field of spray painting equipment, specifically to a non-atomizing coating equipment and a non-atomizing coating process. Background Technology

[0002] Currently, in most metal and plastic parts spraying processes, the color-changing and valve switching modules are located outside the spray booth. After color changing, the paint needs to travel through a long pipeline to reach the inside of the spray booth for spraying. This results in excessively long color-changing time and travel distance, leading to long response times and paint waste due to the long pipeline. Consequently, the color-changing efficiency and spraying accuracy are low, and the overall spraying cost is high. This method also suffers from severe overspraying, resulting in low paint and other coating utilization rates of only about 40%, further increasing the overall spraying cost. In addition, when using robotic arms for spraying, existing fixtures suffer from problems such as excessive length, insufficient rigidity, and poor connection stability. During prolonged spraying, the spraying fixture and nozzle shake significantly, leading to unstable spraying quality. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of existing products and provide a fog-free coating equipment and a fog-free coating process.

[0004] The technical solution adopted in this invention is: a non-atomizing coating equipment, which includes a high-pressure feeding system, a coating robot, and a non-atomizing spraying device; wherein, the high-pressure feeding system includes an air booster pump, an air storage tank, a PLC control module, an air source control valve group connected to the PLC control module, several paint pressure storage tanks, a solvent storage tank, and a diaphragm pump; the non-atomizing spraying device is installed on the execution end of the coating robot via a clamp, and the non-atomizing spraying device integrates a color-changing valve group, which includes a paint pneumatic valve, a solvent pneumatic valve, and a return pneumatic valve; The air source control valve group includes: a pressure tank flow control proportional valve connected to the paint pressure storage tank, a spraying pressure control valve connected to the spraying device, a paint solenoid valve connected to the paint pneumatic valve, a solvent solenoid valve connected to the solvent pneumatic valve, and a return solenoid valve connected to the return pneumatic valve. The atomized spraying device includes a nozzle body, which has a rectangular main body. One side of the main body extends outward at an angle and is provided with a paint inlet, a solvent inlet, and a return inlet. The paint inlet is located in the middle, the solvent inlet is located at one end, and the return inlet is located at the other end. The bottom of the main body is provided with a paint outlet and a solvent outlet. A nozzle plate is also connected to the bottom of the main body. The nozzle plate has a concave space connecting the paint outlet and the solvent outlet. The nozzle plate is also provided with several spray holes with a diameter of less than 150 micrometers. The main body is also equipped with a paint pneumatic valve connected to the paint inlet, a solvent pneumatic valve connected to the solvent inlet, and a return pneumatic valve connected to the return inlet. The coating interface is connected to a multi-port coating valve, which is connected in parallel to the several coating pressure tanks via several coating pipes; the solvent tank is connected to a diaphragm pump and a solvent pneumatic valve via pipelines to supply cleaning solvent to the inside of the nozzle body; the return pneumatic valve is connected to an external waste liquid recovery pipeline. Furthermore, in the aforementioned atomized spraying equipment, the nozzle plate includes a rectangular plate-shaped body that is in contact with the bottom surface of the nozzle body. A strip groove is formed on the mating surface of the plate-shaped body. The strip groove is connected to the paint outlet and solvent outlet on the bottom surface of the nozzle body. The two end walls and the middle wall of the strip groove are provided with arc-shaped portions with a diameter greater than the width of the strip groove. Several spray holes with a diameter of less than 150 micrometers are opened on the bottom surface of the strip groove facing the outer bottom surface of the plate-shaped body opposite to the mating surface. In the plate-shaped body, the depth of the strip groove accounts for 1 / 3 of the thickness of the plate-shaped body, the axial depth of the spray holes accounts for 2 / 3 of the thickness of the plate-shaped body, and the distance between the axes of adjacent spray holes is 0.5mm to 0.6mm. The plate-shaped body is 3mm thick, the depth of the strip groove is 1mm, the axial depth of the spray holes is 2mm, and the distance between the axes of adjacent spray holes is 0.53mm.

[0005] Furthermore, in the aforementioned atomized spraying equipment, the atomized spraying device is connected to the spraying robot via a nozzle fixing clamp; the nozzle fixing clamp includes a hollow tubular body, one end of which is provided with a flange-type connection, and the other end is externally fitted with a nozzle mounting seat, the nozzle mounting seat having at least one bracket mounting surface, and a nozzle fixing bracket connected to the bracket mounting surface.

[0006] Furthermore, in the aforementioned atomized spraying equipment, the nozzle mounting base is generally rectangular in shape, with one side having an inwardly facing connecting recess for the end of the hollow tubular body to pass through. The nozzle mounting base also has a set of first connecting holes that penetrate the connecting recess and a pair of sidewalls. The corresponding end of the hollow tubular body also has a second connecting hole that is coaxially arranged with the first connecting hole.

[0007] Furthermore, in the aforementioned atomized spraying equipment, two adjacent sides of the nozzle mounting base are respectively set as bracket mounting surfaces, and nozzle fixing brackets are installed on the bracket mounting surfaces; the nozzle fixing brackets are respectively provided with two protruding connecting blocks that are connected to the nozzles; a wire-passing window is opened on the side wall of the hollow tubular body.

[0008] The present invention also provides a non-atomizing coating process, which is carried out using a non-atomizing coating equipment, and includes the following steps: (1) setting the spraying parameters through the system, including pressure parameters, spraying area, robot movement trajectory, etc.; (2) fixing the workpiece on the fixture, and spraying the workpiece by driving the spraying device through the robot.

[0009] The coating equipment and coating process of this invention have the following advantages: 1. They can improve the spraying utilization rate, avoid the problem of excessive paint waste on non-spraying surfaces, and save production costs; 2. They do not produce atomization rebound, avoiding the formation of particulate paint mist defects, thus improving the product qualification rate and reducing production costs; 3. The paint utilization rate is increased from less than 40% in the traditional way to more than 80%, thereby significantly reducing the generation of waste and making it more environmentally friendly. Attached Figure Description

[0010] Figure 1 This is a block diagram of the atomization-free coating equipment of the present invention; Figures 2-4 This is a schematic diagram of the nozzle device in this invention; Figure 5 , Figure 6 This is a schematic diagram of the nozzle plate in this invention; Figure 7 , Figure 8 This is a schematic diagram of the nozzle fixing clamp in this invention. Detailed Implementation

[0011] The present invention will be further described below with reference to specific embodiments and accompanying drawings.

[0012] like Figures 1-3 As shown in the figure, this embodiment describes a non-atomizing coating equipment, which includes a high-pressure feeding system, a coating robot 9, and a non-atomizing spraying device 8. The high-pressure feeding system includes an air booster pump 1, an air storage tank 2, a PLC control module 3, an air source control valve group 4 connected to the PLC control module 3, several paint pressure storage tanks 5, a solvent storage tank 6, and a diaphragm pump 7. The non-atomizing spraying device 8 is installed on the execution end of the coating robot 9 by a clamp, and the non-atomizing spraying device 8 integrates a color-changing valve group 83, which includes a paint pneumatic valve 831, a solvent pneumatic valve 832, and a return pneumatic valve 833. The air source control valve group 4 includes: a pressure tank flow control proportional valve 41 connected to the paint pressure storage tank 5 (to control the air pressure and use the air pressure to pressurize and deliver the paint in the paint pressure storage tank to the atomizing spraying device), a spraying pressure control valve 42 connected to the atomizing spraying device 8 (to control the spraying pressure of the nozzle body), a paint solenoid valve 43 connected to the paint pneumatic valve 831, a solvent solenoid valve 44 connected to the solvent pneumatic valve 832, and a return solenoid valve 45 connected to the return pneumatic valve 833; the pneumatic valves of the color changing valve group are controlled by the solenoid valves in the air source control valve group, and the pneumatic valves are integrated on the nozzle body, which can significantly shorten the response time, improve the color changing efficiency, and reduce the waste of color changing paint; The atomized spraying device 8 includes a nozzle body, which has a rectangular main body 81. One side of the main body 81 extends outward at an angle and is provided with a paint inlet 811, a solvent inlet 812, and a return inlet 813. The paint inlet 811 is located in the middle, the solvent inlet 812 is located at one end, and the return inlet 813 is located at the other end. The bottom of the main body 81 is provided with a paint outlet and a solvent outlet. A nozzle plate 82 is also connected to the bottom of the main body 81. The nozzle plate 82 has an opening that connects to the paint outlet, The concave space 821 of the solvent outlet and the nozzle plate 821 are provided with a number of nozzle holes 820 with an aperture of less than 150 micrometers; the main body 81 is also equipped with a paint pneumatic valve 831 connected to the paint interface 811, a solvent pneumatic valve 832 connected to the solvent interface 812, and a return pneumatic valve 833 connected to the return interface 813. The paint interface 811 is connected to the paint pipeline to allow the paint to enter the nozzle body 81, and the solvent interface 812 is connected to the cleaning solvent pipeline to clean the paint of the previous color remaining inside the nozzle body 81 before changing the color. The paint interface 811 is connected to a multi-port paint valve 51, which is connected in parallel to the paint pressure tanks 5 via several paint pipes; the solvent tank 6 is connected to the diaphragm pump 7 and the solvent pneumatic valve 832 via pipelines to supply cleaning solvent to the inside of the nozzle body 81; the return pneumatic valve 833 is connected to the waste liquid recovery pipeline. A spare paint channel 814 is provided on the other side of the facade of the main body 81, extending outward at the center, so as to connect to another paint supply pipeline or pressure tank when needed.

[0013] In this invention, the pneumatic valves controlling the paint and solvent are integrated and installed on the nozzle body, thereby significantly shortening the length of the common path for different colored paints. The cleaning path and area for cleaning solvent during color change are also smaller, thus minimizing the waste of paint and cleaning solvent. The color change and on / off reaction time is shortened to 0.02 seconds, and the spraying response speed and accuracy are greatly improved, saving paint and reducing the overall cost of spraying.

[0014] Furthermore, in the aforementioned atomized spraying equipment, the nozzle plate 82 includes a rectangular plate-shaped body 821 that is connected to the bottom surface of the nozzle body 81. A strip groove 8211 is formed on the mating surface of the plate-shaped body 821. The strip groove 8211 is connected to the paint outlet and solvent outlet on the bottom surface of the nozzle body. The two end walls and the middle wall of the strip groove 8211 are provided with arc-shaped portions 8212 with a diameter greater than the width of the strip groove 8211. The three arc-shaped portions 8212 have suitable space for the installation and operation of the paint pneumatic valve 811, solvent pneumatic valve 812 and return pneumatic valve 813 on the nozzle body. A number of spray holes 820 with a diameter of less than 150 micrometers are opened on the bottom surface of the strip groove 8211 facing the outer bottom surface of the plate-shaped body 821 opposite to the mating surface. The preferred hole diameter is 100 micrometers to 120 micrometers.

[0015] In the plate-shaped body 821, the depth of the strip groove is 1 / 3 of the thickness of the plate-shaped body, the axial depth of the spray hole is 2 / 3 of the thickness of the plate-shaped body, and the distance between the axes of adjacent spray holes is 0.5mm to 0.6mm. In this embodiment, the thickness of the plate-shaped body 821 is 3mm, then the depth of the strip groove 8211 is 1mm, the axial depth of the spray hole 820 is 2mm, and the distance between the axes of adjacent spray holes is 0.53mm. Under these conditions, the coating flow spraying effect is optimal, with good uniformity and less rebound, resulting in more precise spraying.

[0016] With the above-described structure, this invention eliminates the need for compressed air as an atomization power source during spraying. The paint is transported from a pressure tank and pipeline, passes through the nozzle, and reaches the strip groove 8211 within the nozzle plate. The space within the strip groove 8211 ensures uniform paint pressure, which is then extruded through the spray holes 820 to form a uniformly sized paint stream, which is then sprayed onto the product surface. Because there is no air, there is no atomization, thus preventing paint rebound and other phenomena. This solves environmental problems and potential health hazards to workers, and also avoids serious overspray. Overall, the paint utilization rate reaches over 80%, which helps reduce spraying costs.

[0017] Furthermore, in the aforementioned atomized spraying equipment, the atomized spraying device 8 is connected to the spraying robot 9 via a nozzle fixing clamp 91; the nozzle fixing clamp 91 includes a hollow tubular body 911, one end of which is provided with a flange-type connection 9111, and the other end is externally fitted with a nozzle mounting seat 9112, the nozzle mounting seat 9112 having at least one bracket mounting surface 91121, and a nozzle fixing bracket 9113 connected to the bracket mounting surface 91121.

[0018] Specifically, the nozzle mounting base 9112 is generally rectangular in shape, with a connecting recess 91122 on one side facing inward for the end of the hollow tubular body 911 to pass through. The nozzle mounting base 9112 also has a set of first connecting holes 91123 that penetrate the connecting recess 91122 and a pair of sidewalls. The corresponding end of the hollow tubular body 911 also has a second connecting hole 91101 that is coaxially arranged with the first connecting hole 91123. The nozzle mounting base 9112 is fixedly connected to the hollow tubular body 911 by bolts through the first connecting hole 91123 and the second connecting hole 91101. The two adjacent sides of the nozzle mounting base 9112 are respectively set as bracket mounting surfaces 91121, and the nozzle fixing bracket 9113 is installed on the bracket mounting surface 91121. The nozzle fixing bracket 9113 is provided with two protruding connecting blocks 91131 that are connected to the nozzle, and the space between the protruding connecting blocks 91131 is used to avoid the spare paint inlet 9121 on the nozzle.

[0019] A wire-passing window 91102 is provided on the side wall of the hollow tubular body 911, which facilitates the arrangement of most of the pipes or wires inside the hollow tubular body 911, and they pass through the wire-passing window 91102 to connect to the nozzle, thus maintaining a neat overall appearance.

[0020] The nozzle fixing fixture body 911 of this invention adopts a hollow tubular design to achieve lightweight construction. A flange-type connection 9111 is provided at one end of the hollow tubular body 911, facilitating stable installation of the fixture as a whole. It also allows the fixture to be mounted on a robotic arm. The hollow and lightweight design reduces the load on the robotic arm, enabling smoother and more precise spraying and ensuring spray quality. The nozzle mounting base 9112 has multiple nozzle mounting positions, allowing users to choose to use one or multiple nozzles simultaneously as needed, thereby improving spraying efficiency. Furthermore, this invention has a simple structure and is very convenient to assemble and use.

[0021] The present invention also provides a non-fogging coating process, which is carried out using the above-mentioned non-fogging coating equipment, and includes the following steps: (1) setting the spraying parameters through the system, including pressure parameters, color pattern, spraying area, robot movement trajectory, etc.; (2) fixing the workpiece on the fixture, and spraying the workpiece by driving the spraying device through the robot.

[0022] In this invention, the air booster pump and air tank of the high-pressure feeding system provide a stable pneumatic power source, and the pneumatic power is provided by the PLC control module and the air source control valve group respectively; on the one hand, the pressure of the paint pressure storage tank is controlled to realize pressurized feeding, so that the paint in it is supplied to the spraying device and enters the nozzle body through the paint pneumatic valve, and then, in conjunction with the spraying pressure control valve and the nozzle plate, it is sprayed onto the workpiece to achieve atomized spraying; When changing colors, the solvent pneumatic valve in the color-changing valve group is controlled by the solvent solenoid valve. The air source drives the diaphragm pump to pump solvent from the solvent storage tank into the nozzle body. At the same time, the paint in another set of paint pressure storage tanks is supplied to the nozzle body to cover the remaining paint from the previous one. Together with the cleaning solvent, the nozzle body is cleaned. The waste liquid after cleaning is discharged and recycled through the return pneumatic valve from the return port, thus completing the color change. In this way, the color change cleaning is concentrated inside the nozzle body, so less waste liquid and less solvent are generated. It can reduce the color change time, save paint and solvent, and improve the paint utilization rate, which can reach more than 80%.

[0023] In summary, the coating equipment and coating process of the present invention have the following advantages: 1. It can improve the utilization rate of spraying, avoid the problem of excessive paint waste on non-spraying surfaces, and save production costs; 2. No atomization rebound occurs, avoiding defects such as particulate paint mist, thus improving product qualification rate and reducing production costs; 3. Paint utilization rate has increased from below 40% to over 80%, thereby significantly reducing waste generation and making it more environmentally friendly.

Claims

1. A fog-free coating equipment, characterized in that: The atomless coating equipment includes a high-pressure feeding system, a coating robot, and an atomless spraying device. The high-pressure feeding system includes an air booster pump, an air tank, a PLC control module, an air source control valve group connected to the PLC control module, several paint pressure tanks, a solvent tank, and a diaphragm pump. The atomless spraying device is mounted on the actuator end of the coating robot via a clamp, and integrates a color-changing valve group, which includes a paint pneumatic valve, a solvent pneumatic valve, and a return pneumatic valve. The air source control valve group includes: a pressure tank flow control proportional valve connected to the paint pressure storage tank, a spraying pressure control valve connected to the atomized spraying device, a paint solenoid valve connected to the paint pneumatic valve, a solvent solenoid valve connected to the solvent pneumatic valve, and a return solenoid valve connected to the return pneumatic valve. The atomized spraying device includes a nozzle body, which has a rectangular main body. One side of the main body extends outward at an angle and is provided with a paint inlet, a solvent inlet, and a return inlet. The paint inlet is located in the middle, the solvent inlet is located at one end, and the return inlet is located at the other end. The bottom of the main body is provided with a paint outlet and a solvent outlet. A nozzle plate is also connected to the bottom of the main body. The nozzle plate has a concave space connecting the paint outlet and the solvent outlet. The nozzle plate is also provided with several spray holes with a diameter of less than 150 micrometers. The main body is also equipped with a paint pneumatic valve connected to the paint inlet, a solvent pneumatic valve connected to the solvent inlet, and a return pneumatic valve connected to the return inlet. The coating interface is connected to a multi-port coating valve, which is connected in parallel to the several coating pressure tanks through several coating pipes; the solvent tank is connected to a diaphragm pump and a solvent pneumatic valve through pipelines to supply cleaning solvent to the inside of the nozzle body; the return pneumatic valve is connected to a waste liquid recovery pipeline.

2. The atomization-free coating equipment according to claim 1, characterized in that: The nozzle plate includes a rectangular plate-shaped body that is in contact with the bottom surface of the nozzle body. A strip groove is formed on the mating surface of the plate-shaped body. The strip groove is connected to the paint outlet and solvent outlet on the bottom surface of the nozzle body. The two ends and the middle of the groove have arc-shaped portions with a diameter greater than the width of the strip groove. Several spray holes with a diameter of less than 150 micrometers are formed on the bottom surface of the strip groove facing the bottom surface of the plate-shaped body opposite to the mating surface. In the plate-shaped body, the depth of the strip groove accounts for 1 / 3 of the thickness of the plate-shaped body, the axial depth of the spray holes accounts for 2 / 3 of the thickness of the plate-shaped body, and the distance between the axes of adjacent spray holes is 0.5mm to 0.6mm. The plate-shaped body is 3mm thick, the depth of the strip groove is 1mm, the axial depth of the spray holes is 2mm, and the distance between the axes of adjacent spray holes is 0.53mm.

3. The atomization-free coating equipment according to claim 1, characterized in that: The atomized spraying device is connected to the coating robot via a nozzle fixing clamp; the nozzle fixing clamp includes a hollow tubular body, one end of which is provided with a flange connection, and the other end is externally fitted with a nozzle mounting seat. The nozzle mounting seat has at least one bracket mounting surface, and a nozzle fixing bracket is connected to the bracket mounting surface.

4. The atomization-free coating equipment according to claim 3, characterized in that: The nozzle mounting base is generally rectangular in shape. One side of the nozzle mounting base has a connecting recess for the end of the hollow tubular body to pass through. The nozzle mounting base also has a set of first connecting holes that pass through the connecting recess and a pair of side walls. The corresponding end of the hollow tubular body also has a second connecting hole that is coaxially arranged with the first connecting hole.

5. The atomization-free coating equipment according to claim 3, characterized in that: The two adjacent sides of the nozzle mounting base are respectively set as bracket mounting surfaces, and nozzle fixing brackets are installed on the bracket mounting surfaces; the nozzle fixing brackets are respectively provided with two protruding connecting blocks that are connected to the nozzles; a wire-passing window is opened on the side wall of the hollow tubular body.

6. A fog-free coating process, characterized in that: The process is carried out using the atomless coating equipment described in any one of claims 1-5, and includes the following steps: (1) setting the spraying parameters through the high-pressure feeding system, including pressure parameters, spraying area, and the movement trajectory of the coating robot; (2) fixing the workpiece on the fixture and spraying it by driving the atomless spraying device through the coating robot.

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