A spray coating apparatus

Abstract

The application discloses a spraying device and relates to the technical field of spraying processing equipment.The spraying device comprises a machine body, a spraying cavity assembly arranged in the machine body, and a conveying mechanism arranged on the machine body.The conveying mechanism is used for conveying target workpieces.The spraying cavity assembly is arranged below the conveying mechanism and comprises a spraying cabinet and a flow guide groove which are fixedly connected in an integrated manner.A sliding guide structure is arranged in the spraying cabinet.A spraying gun assembly is pullably arranged in the spraying cabinet through the sliding guide structure.The spraying gun assembly is switched between a spraying position in the spraying cabinet and a maintenance position in which the spraying cabinet is at least partially pulled out based on the sliding guide structure.The mechanical structure of the spraying cavity assembly is simplified, and the operation stability and the maintenance convenience are improved.

Description

Technical Field

[0001] This invention relates to the field of spraying technology, and more specifically to a spraying device. Background Technology

[0002] In the field of surface coating processing of sheet products, spraying equipment typically includes a frame, conveying components, spraying components, and paint recovery mechanism. Existing spraying equipment requires shutdown and disassembly and cleaning of the spraying components during the cleaning process.

[0003] Complex lifting mechanisms, pulley systems, and guide rail systems are often incorporated into the spraying components, resulting in a bulky overall equipment structure, high failure rate, and poor operational stability. Furthermore, during shutdowns, color changes, or troubleshooting, existing technologies often employ physical gates at the nozzles to prevent paint from spraying onto the conveyor belt. However, since the feeding system typically cannot be stopped immediately, a large amount of paint remains in the spray guns and pipelines, not only wasting raw materials but also easily leading to secondary contamination due to paint curing or deterioration, increasing cleaning difficulty and production costs. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art. This invention provides a spraying device that, by setting a retractable spray gun assembly, achieves a simplified and stable device structure and improves the convenience of device maintenance.

[0005] This invention provides a spraying device, which includes: a body, a spraying chamber assembly disposed within the body, and a conveying mechanism disposed on the body; The conveying mechanism is used to convey the target workpiece; The spraying chamber assembly is located below the conveying mechanism. The spraying chamber assembly includes an integrated and fixedly connected spraying cabinet and a guide trough. The spraying cabinet is provided with a sliding guide structure. The spray gun assembly is removably installed in the spraying cabinet through the sliding guide structure. The spray gun assembly switches between a spraying position inside the spraying cabinet and a maintenance position at least partially removed from the spraying cabinet based on the sliding guide structure.

[0006] Furthermore, the sliding guide structure includes a guide rail disposed on the inner wall of the spray booth and a slider disposed on the bottom of the spray gun assembly. The slider slides in cooperation with the guide rail so that the spray gun assembly can move along the guide rail between the spraying position and the maintenance position.

[0007] Furthermore, the spray gun assembly includes a pipe, multiple nozzles, and a mounting plate. The multiple nozzles are distributed along the length of the pipe, one end of the pipe is fixed to the mounting plate, and the bottom of the mounting plate is provided with the slider.

[0008] Furthermore, one end of the spray gun assembly is locked to the end of the spray booth by a fastener, and the end of the spray booth is provided with an opening for the spray gun assembly to pass through; when the fastener is loosened, the spray gun assembly can be pulled out along the opening to the maintenance position.

[0009] Furthermore, the spray booth is also equipped with a pneumatic baffle mechanism, which includes a cylinder and a gear and rack transmission assembly that is connected to the cylinder. The gear and rack transmission assembly includes a rack driven by the cylinder to perform linear motion and a gear meshing with the rack. The gear is connected to the baffle, and the baffle switches between the blocking position and the retracted position through the gear and rack transmission assembly under the drive of the cylinder. At the shielding position, the baffle shields the spraying area of ​​the spray gun assembly.

[0010] Furthermore, the spraying equipment also includes a diversion and return mechanism disposed in the paint pipeline. The diversion and return mechanism includes a switching valve assembly, which has a first port, a second port, and a third port. The first port is connected to the material supply source, the second port is connected to the spray gun assembly, and the third port is connected to the return end. In the spraying flow path, the first port is connected to the second port; in the return flow path, the first port is connected to the third port.

[0011] Furthermore, the switching valve assembly is a three-way valve assembly, and the three-way valve assembly is internally provided with a valve core and a power component for driving the valve core to rotate; The valve core has a first flow channel connecting the first port and the second port, and a second flow channel connecting the first port and the third port.

[0012] Furthermore, the conveying mechanism includes a conveyor belt and water-blocking strips disposed on both sides of the conveyor belt, the water-blocking strips extending along the conveying direction of the conveyor belt.

[0013] Furthermore, an integrated through-type material collection trough is provided below the conveying mechanism. The integrated through-type material collection trough extends along the conveying direction of the conveying mechanism, and the opening of the integrated through-type material collection trough faces the conveying mechanism.

[0014] Furthermore, the conveying mechanism includes multiple rollers, a first drive motor, and a transmission mechanism. The multiple rollers are disposed within the transmission mechanism, the output shaft of the first drive motor is connected to the transmission mechanism, and the first drive motor drives the multiple rollers based on the transmission mechanism.

[0015] This invention provides a spraying device that, through a sliding guide structure set inside the spraying cabinet, allows the spray gun assembly to flexibly switch between the spraying position and the maintenance position. While ensuring the sealing of normal spraying operations, it enables the rapid pull-out maintenance of the spray gun assembly and solves the technical problem of the difficulty in cleaning fixed cavities. Attached Figure Description

[0016] 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, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the spraying equipment in an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of the spraying chamber assembly of the spraying equipment in an embodiment of the present invention; Figure 3 This is an exploded view of the spraying chamber assembly of the spraying equipment in an embodiment of the present invention; Figure 4 This is a schematic diagram of the paint recycling mechanism of the spraying equipment in an embodiment of the present invention; Figure 5 This is a schematic diagram of the paint recycling mechanism of the spraying equipment from another perspective in an embodiment of the present invention; Figure 6 This is an exploded view of the spraying chamber assembly of the spraying equipment in an embodiment of the present invention; Figure 7 This is a schematic diagram of the spraying equipment according to Embodiment 2 of the present invention; Figure 8 This is an exploded view of the spraying equipment according to Embodiment 2 of the present invention; Figure 9 This is an appendix to the embodiments of the present invention. Figure 8 An enlarged schematic diagram of the structure at point A.

[0018] Figure label: 100. Conveying mechanism; 110. Roller; 120. First drive motor; 130. Scraper; 200. Spraying chamber assembly; 210. Spraying cabinet; 220. Guide channel; 230. Sliding guide structure; 240. Spray gun assembly; 241. Pipeline; 242. Nozzle; 243. Mounting plate; 260. Pneumatic baffle mechanism; 261. Cylinder; 262. Gear and rack transmission assembly; 263. Baffle; 300. Feeding pipeline; 400. Paint recovery mechanism; 410. Scraper assembly; 411. Scraper mounting frame; 412. Scraper; 420. Conveyor belt; 430. Integrated through-type collection trough; 440. Limiting wheel; 450. Baffle plate; 460. Second drive motor; 470. Drag wheel assembly; 500. Frame; 510. Paint recovery tray; 511. Paint collection trough. Detailed Implementation

[0019] 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.

[0020] Example 1: Please refer to Figures 1 to 6 This embodiment provides a spraying device, which includes a frame 500, a conveying mechanism 100, a spraying cavity assembly 200, and a feeding pipeline 300 disposed within the frame 500. The conveying mechanism 100 is configured to convey the target workpiece. The conveying mechanism 100 can be a roller conveyor. By placing the spraying end of the spraying cavity assembly 200 inside the roller conveyor, when the plate workpiece is conveyed by the roller conveyor, the spraying cavity assembly 200 can be used to perform paint spraying operations.

[0021] Specifically, in this embodiment, the conveying mechanism 100 includes multiple rollers 110, a first drive motor 120, and a transmission mechanism. The multiple rollers 110 are disposed within the transmission mechanism. The output shaft of the first drive motor 120 is connected to the transmission mechanism, and the first drive motor 120 drives and connects to the multiple rollers 110 based on the transmission mechanism. The first drive motor 120 drives and connects to the transmission mechanism. That is, the first drive motor 120 serves as a power source, and transmits the rotational torque synchronously to each roller 110 through the transmission mechanism to ensure that the conveying mechanism can smoothly and uniformly pass the product through the spraying processing area.

[0022] Specifically, the outer circumferential wall of the roller 110 is provided with a plurality of circular plates. The circular plates of any two adjacent rollers 110 are staggered. From the perspective of contact mechanics, the circular plates transform the traditional "surface contact" between the roller and the product into discrete "point contact" or "line contact". When the bottom surface of the product is coated with uncured wet paint, this extremely small contact area significantly reduces the adhesion force of the roller to the coating and the risk of shear damage, avoiding coating peeling or uneven thickness caused by excessive contact area.

[0023] Secondly, from the perspective of motion stability, although the discs on a single roller 110 are spaced apart, the discs on adjacent rollers are staggered in the axial direction, and these discrete support points together form a continuous "virtual support plane" in space. This virtual plane retains the advantage of reducing the contact area and effectively prevents the product from flexing or deforming due to local suspension or from lateral displacement in the conveying direction.

[0024] Furthermore, each roller 110 is provided with water-blocking O-rings at both ends. The O-rings are fitted around the outer circumference of the shaft end of the roller 110 to prevent cleaning water or paint liquid from seeping into the bearing or transmission assembly along the roller axis and to avoid water corrosion of the end parts.

[0025] Furthermore, a scraper 130 can be installed below each roller 110. The cutting edge of the scraper 130 maintains a preset gap or slight contact with the outer surface of the disc of the roller 110 to scrape off residual paint or impurities adhering to the surface of the disc of the roller 110, thus maintaining the surface cleanliness of the disc of the roller 110. A fixed return trough is also provided below the conveying mechanism 100. The fixed return trough is fixedly connected to the equipment frame and is used to collect paint dripping from the conveying mechanism 100 and guide it to a designated recycling container. This replaces the traditional draggable return trough structure, simplifies maintenance operations, and improves structural stability.

[0026] Specifically, the spraying chamber assembly 200 is disposed below the conveying mechanism 100. The spraying chamber assembly 200 includes an integrally fixedly connected spraying cabinet 210 and a guide channel 220. The output port of the guide channel 220 is disposed within the roller conveying device of the conveying mechanism 100. The spraying cabinet 210 is provided with a sliding guide structure 230, and a spray gun assembly 240 is retractably disposed within the spraying cabinet 210 via the sliding guide structure 230. The spray gun assembly 240 is configured to switch between a spraying position located inside the spraying cabinet 210 and a maintenance position at least partially withdrawn from the spraying cabinet 210. The spray gun assembly 240 is used to spray paint, causing the paint to be sprayed along the guide channel 220 onto the workpiece of the conveying mechanism 100.

[0027] Specifically, the sliding guide structure 230 provides a trajectory constraint for the linear reciprocating motion of the spray gun assembly 240, allowing it to be smoothly pulled out or pushed in from the front opening of the spray booth 210 like a drawer. When the spray gun assembly 240 is in the spraying position, it is fully contained inside the spray booth 210, with the nozzle facing the predetermined spraying area below the conveyor mechanism 100. When nozzle cleaning, replacement, or internal maintenance is required, the operator can pull the spray gun assembly 240 out along the sliding guide structure 230 to the maintenance position, exposing the spray gun and auxiliary pipelines to the external open space, thus allowing for convenient maintenance without disassembling the entire spraying chamber.

[0028] Specifically, the feed line 300 includes a diversion and return mechanism. This mechanism has a spray path connecting the feed source and the spray gun assembly 240, and a return path connecting the feed source and the return end. Specifically, the diversion and return mechanism can be a three-way valve, a multi-way rotary valve, or a valve assembly block, installed on the main path of the feed line 300, located between the feed source (such as a paint bucket or feed pump outlet) and the spray gun assembly 240. This mechanism has three key physical interfaces: an inlet connected to the feed source, a first outlet connected to the paint inlet of the spray gun assembly 240 via a hose or rigid pipe, and a second outlet connected to the return end (such as the return port of the raw material bucket or a waste liquid collection container). Through mechanical switching of the internal valve core or flow channel, the diversion and return mechanism can physically switch between two fluid path states, rather than relying solely on software logic or electrical signal control.

[0029] At the spraying position, the diversion and recirculation mechanism opens the spraying path; at the maintenance position or when the machine is stopped, the diversion and recirculation mechanism opens the recirculation path. Specifically, when the equipment is operating normally, the internal channel of the diversion and recirculation mechanism connects the material supply source to the spray gun assembly 240, and the paint is transported to the nozzle for atomization and spraying via the spraying path. When the equipment stops, malfunctions, or the spray gun assembly 240 is pulled out to the maintenance position, the diversion and recirculation mechanism automatically or manually switches to the recirculation state, cutting off the paint supply to the spray gun assembly 240, and simultaneously guiding the paint output from the material supply source directly back to the material tank or designated recycling end via the recirculation path. This design, which switches the flow path at the material supply source, replaces the traditional solution of setting a physical gate at the nozzle for blocking, fundamentally avoiding the retention and solidification of paint in the spray gun and long-distance pipeline during shutdown. This not only eliminates material waste but also prevents secondary pollution caused by paint deterioration, significantly reducing cleaning frequency and maintenance costs. Meanwhile, since the diversion and return mechanism is an independent physical hardware module, its flow path switching action is reliable and responds quickly, providing a solid mechanical execution foundation for intelligent control based on electrical signals in subsequent embodiments.

[0030] Specifically, in this embodiment, the sliding guide structure 230 includes a guide rail disposed on the inner wall of the spray booth 210 and a slider disposed on the bottom of the spray gun assembly 240. The slider slides in cooperation with the guide rail, allowing the spray gun assembly 240 to move along the guide rail between the spraying position and the maintenance position. Specifically, the guide rail is rigidly fixed to the bottom of the inner wall of the spray booth 210 by bolts or welding, and is arranged horizontally along the longitudinal direction of the spray booth 210, providing a trajectory constraint for the linear reciprocating motion of the spray gun assembly 240. The slider is fixedly connected to the bottom of the mounting plate of the spray gun assembly 240 and moves synchronously with the spray gun assembly 240. The mating surfaces of the guide rail and the slider can be made of low-friction engineering plastic gaskets or linear bearings to reduce frictional resistance and wear during the pulling process.

[0031] Furthermore, the spray gun assembly 240 includes a pipe 241, multiple nozzles 242, and a mounting plate 243. The multiple nozzles 242 are distributed along the length of the pipe 241. One end of the pipe 241 is fixed to the mounting plate 243, and a slider is provided at the bottom of the mounting plate 243. Specifically, the pipe 241 is a hollow tubular structure, and its inner cavity forms a paint flow channel. The multiple nozzles 242 are installed on the upper or side surface of the pipe 241 at equal or unequal intervals along the axial direction of the pipe 241. The number and spacing of the nozzles 242 can be adaptively adjusted according to the spray width and coating uniformity requirements. One end of the pipe 241 is fixed to the mounting plate 243 by a flange or threaded connection. The mounting plate 243 serves as the support base of the spray gun assembly 240, and its bottom is provided with a slider that mates with a guide rail. The mounting plate 243 can be made of aluminum alloy, stainless steel, or engineering plastics, etc., to ensure structural rigidity while also being lightweight.

[0032] Furthermore, one end of the spray gun assembly 240 is locked to the end of the spray booth 210 by fasteners, and the end of the spray booth 210 has an opening for the spray gun assembly 240 to pass through. Specifically, the fasteners can be bolts, screws, or quick-lock clips, etc., to fix the end of the pipe 241 or the mounting plate 243 of the spray gun assembly 240 to the end wall of the spray booth 210. When the equipment is operating normally, the fasteners firmly lock the spray gun assembly 240 in the spraying position, preventing displacement due to vibration or fluid pressure; when the nozzle 242 needs to be cleaned or replaced, the operator only needs to loosen the fasteners to pull the spray gun assembly 240 out along the opening to the maintenance position, without disassembling the entire spraying chamber. This detachable connection method takes into account both the stability in the working state and the convenience in the maintenance state.

[0033] In this embodiment, the diversion and return mechanism includes a switching valve assembly. The switching valve assembly has a first port, a second port, and a third port. The first port is connected to the material supply source, the second port is connected to the spray gun assembly 240, and the third port is connected to the return end. Specifically, the switching valve assembly, as the core execution unit for fluid distribution, has three ports arranged in a T-shape or L-shape in physical space. These ports are respectively connected to the upstream material supply pump outlet, the downstream spray gun assembly 240 inlet, and the raw material tank return port via solvent-resistant hoses or rigid pipes to form sealed connections. Inside the valve body, there are independent first and second flow channels. The first flow channel is constructed as a straight or slightly arc-shaped channel, used to directly connect the first and second ports in the conducting state, forming a low-flow-resistance spray material supply path; the second flow channel is constructed as a bent or bypass channel, used to connect the first and third ports in the switching state, forming a paint circulation return path. This built-in dual-channel physical structure design makes the flow path switching rely entirely on the mechanical displacement of the valve core, rather than solely on software logic judgment, thereby ensuring the determinism and reliability of fluid path switching and effectively avoiding the risk of accidental spraying or flow interruption caused by electrical faults.

[0034] Furthermore, the switching valve assembly is a three-way valve assembly, which internally includes a valve core and a power component for driving the valve core to rotate. The valve core has a first flow channel connecting a first port and a second port, and a second flow channel connecting the first port and a third port. The spraying equipment also includes a controller, which is communicatively connected to the power component.

[0035] Furthermore, the power component can employ high-precision stepper motors, AC servo motors, high-precision cylinders, or other drive components. Its output shaft is coaxially and fixedly connected to the valve core or driven by a coupling, enabling precise control of the valve core's rotation angle. The controller can be a PLC, a microcontroller, or a dedicated motion control card, which receives external sensor signals or host computer instructions and sends pulse or analog control signals to the servo motor.

[0036] Furthermore, in this embodiment, an electric three-way valve of model 4M310-08 is used to adapt to the integrated pipeline control requirements of the spraying equipment. The servo motor has a position feedback function, which can monitor the actual rotation angle of the valve core in real time and make closed-loop corrections to ensure the alignment accuracy of the flow channel and prevent internal leakage or crossflow caused by valve core misalignment.

[0037] The controller is configured to acquire the operating status signals of the spraying equipment, including spraying operation signals, shutdown signals, and cleaning signals. When the operating status signal is a spraying operation signal, the controller controls the servo motor to drive the valve core to rotate to a first preset angle, opening the first flow channel to establish a spraying flow path. When the operating status signal is a shutdown signal or a cleaning signal, the controller controls the servo motor to drive the valve core to rotate to a second preset angle, opening the second flow channel to establish a return flow path, and simultaneously sends a pressure reduction command to the material supply source. Specifically, there is a clear phase difference between the first preset angle and the second preset angle. For example, in a preferred embodiment, when the valve core is at the 0° reference position, the first flow channel is fully aligned with the inlet and outlet, which is defined as the spraying operation state; when the controller receives a shutdown or cleaning signal, it drives the servo motor to rotate the valve core 90° clockwise or counterclockwise to the second preset angle. At this time, the first flow channel is blocked by the valve body, and the second flow channel precisely connects the first port and the third port, achieving seamless flow path switching. Considering machining tolerances and assembly errors, the preset angle allows for a tolerance range of ±2° to ±5°, as long as the effective flow area of ​​the flow channel meets the process flow requirements. More importantly, while opening the return flow path, the controller simultaneously sends a pressure reduction command to the material supply source (such as a variable frequency feed pump), rapidly reducing the supply pressure from the spraying working pressure (e.g., 2.0MPa) to a low-pressure state (e.g., 0.3MPa-0.5MPa) to maintain circulation. The physical significance of this coordinated control mechanism is that if switching directly to return flow under high pressure is used, the high-pressure coating will experience severe erosion and cavitation at the moment of switching due to the typically long return pipeline and low back pressure. This not only damages the valve core sealing surface but also easily creates turbulent dead zones at pipeline bends, leading to coating deposition. However, by actively reducing pressure in conjunction with return flow, it ensures that the coating can flow smoothly back to the raw material tank and avoids dripping or atomized residue of high-pressure residual coating in the spray gun barrel due to uneven pressure release, fundamentally eliminating the risk of raw material waste and secondary pollution.

[0038] Specifically, the spraying equipment also includes a paint recovery mechanism 400, which comprises a conveyor belt 410 and water-blocking strips 420 disposed on both sides of the conveyor belt 410. The water-blocking strips 420 extend along the conveying direction of the conveyor belt 410 to prevent paint fluid from entering the inner side of the conveyor belt 410. The water-blocking strips 420 are continuously arranged along both sides of the conveyor belt 410, forming two longitudinally extending fluid barriers. During the spraying operation, the paint sprayed from the nozzle moves downward under the action of gravity, and some paint droplets may splash or flow to the edge area of ​​the conveyor belt. The presence of the water-blocking strips effectively intercepts these fluids, preventing them from crossing the edge of the conveyor belt and entering the inner side of the belt or the transmission component area, thereby protecting the cleanliness and operational stability of the transmission system. The material of the water-blocking strips can be solvent-resistant rubber, polyurethane, or fluoroplastics, and its cross-sectional shape can be rectangular, trapezoidal, or arc-shaped, as long as it can form an effective flow barrier at the edge of the conveyor belt.

[0039] Specifically, the paint recycling mechanism 400 includes a second drive motor 460, a conveyor belt 420, and several scraping assemblies 410. The second drive motor 460 drives and connects to the conveyor belt 420. Each scraping assembly 410 includes a scraping mounting frame 411 and a scraping plate 412. The scraping plate 412 is mounted on the scraping mounting frame 411 and is in contact with the surface of the conveyor belt 420. The conveyor belt 420 has integrated through-type collection troughs 430 on both sides, and the scraping plate 412 is located between the two integrated through-type collection troughs 430. The conveyor belt 420 spans above the conveying mechanism 100, forming an active paint capture interface. This allows the paint sprayed onto the workpiece by the spraying chamber assembly 200 to adhere to the conveyor belt 420. Through the continuous movement of the conveyor belt 420, excess paint adhering to its surface is forcibly transported to a designated scraping station. Based on the scraping assembly 410, the paint on the surface of the conveyor belt 420 is scraped, allowing excess paint to flow along the scraper plate 412 towards the integrated through-type collection trough 430, thereby realizing the recovery of spraying residue.

[0040] Furthermore, the scraper 412 is typically made of a wear-resistant and elastic material, such as PU (Polyurethane). Its cutting edge is in close contact with the surface of the conveyor belt 420. When the conveyor belt 420 passes under the scraper 412, the coating is mechanically peeled off and slides down the guide surface of the scraper 412 into the integrated through-type collection troughs 430 on both sides. Based on the combination of dynamic adsorption and mechanical scraping, the problem of high-viscosity coatings easily solidifying and accumulating on the recycling surface is effectively solved, ensuring the continuous unobstructed flow of the recycling channel.

[0041] Specifically, the output shaft of the second drive motor 460 is connected to the input shaft of the reducer via a coupling, and the output shaft of the reducer is connected to the shaft end of one side of the drive shaft of the conveyor belt 420. An L-shaped fixing plate is fixed to the side wall of the second drive motor 460. The L-shaped fixing plate includes a first plate and a second plate that are perpendicular to each other. The first plate is fitted and fixed to the housing of the second drive motor 460, and the second plate extends outward and is fixed to the frame of the conveying mechanism 100.

[0042] Specifically, the first plate of the L-shaped fixing plate is tightly attached to the side of the cylindrical housing of the second drive motor 460 by bolts, forming a radial clamping and axial positioning of the motor body; the second plate extends outward in a horizontal or inclined direction and is rigidly connected to the main frame of the machine tool by welding or high-strength bolts. This double-sided orthogonal fixing structure design, compared with the traditional method of relying solely on the motor flange end face fixing or single-sided torque arm support, can significantly increase the anti-overturning torque of the second drive motor 460 under starting, braking, and load fluctuation conditions. When the motor output torque generates a reaction force, the second plate of the L-shaped fixing plate directly transmits the lateral load to the frame, effectively avoiding motor housing deformation or fatigue fracture of mounting bolts caused by the cantilever beam effect, thereby improving the overall rigidity and operational stability of the transmission system.

[0043] Furthermore, the coupling, as the intermediate transmission element connecting the output shaft of the second drive motor 460 and the input shaft of the reducer, preferably adopts a flexible pin coupling, diaphragm coupling, or a quincunx flexible coupling, etc., which possess flexible compensation capabilities. During actual assembly and long-term operation, slight coaxiality deviations, angular misalignments, or axial movement inevitably exist between the motor shaft and the reducer shaft. The coupling, utilizing its internal elastic elements or flexible diaphragm structure, can actively absorb and compensate for these installation errors and thermal expansion deformations, avoiding additional bearing loads and shaft vibrations caused by rigid connections. This design fundamentally eliminates common potential faults such as oil leakage from the reducer input end oil seal due to misalignment, overheating and burnout of the motor bearings, and fatigue breakage of the transmission shaft, significantly extending the service life and maintenance cycle of the power transmission components.

[0044] Furthermore, in practical applications, multiple scraping components 410 can be connected in series along the running direction of the conveyor belt 420 to achieve graded cleaning, prevent excessive single scraping load from causing residue, and improve the cleaning effect of the scraping components 410 on the surface of the conveyor belt 420, thereby avoiding secondary pollution of the product surface by spraying residue. Furthermore, the integrated through-type collection trough 120 extends along the conveying direction of the paint recovery mechanism 400, and the opening of the integrated through-type collection trough 120 faces the paint recovery mechanism 400 to collect fluid dripping from the paint recovery mechanism 400. The integrated through-type collection trough 120 includes a tank shell and a flow guide bottom plate disposed inside the tank shell. Multiple transverse reinforcing ribs are spaced apart inside the tank shell along the conveying direction of the paint recovery mechanism 400. The bottom of each transverse reinforcing rib is fixedly connected to the flow guide bottom plate, and the top is fixedly connected to the top wall of the tank shell.

[0045] Specifically, the 120mm long integrated collection trough covers the entire longitudinal span of the spraying area. Its continuous, seamless structure replaces the traditional segmented collection trough, completely eliminating the risk of seal failure at the joints and preventing leakage due to aging or misalignment. The guide plate can be angled along the conveying direction, allowing the collected fluid to flow smoothly to the drain port under gravity. The transverse reinforcing ribs serve a dual function: firstly, as structural supports, they are rigidly connected to the trough top and guide plate at their upper and lower ends, dividing the long-span trough into multiple mechanical units. This significantly improves the overall bending and torsional rigidity of the collection trough, preventing deformation and sagging due to its own weight or accumulated liquid load. Secondly, guide holes can be opened on the transverse reinforcing ribs to ensure free flow of fluid within each segment, ultimately converging at the drain port and preventing the formation of isolated dead zones.

[0046] Furthermore, the paint recycling mechanism 400 also includes multiple limiting wheels 440 disposed on both sides of the belt. The limiting wheels 440 are spaced apart along the conveying direction, and the central axis of each limiting wheel 440 is set in the vertical direction, that is, the central axis of the limiting wheel 440 is perpendicular to the conveying direction of the conveyor belt 420, so that the outer circumferential contour of the limiting wheel 440 is tangent to the side wall of the conveyor belt 420. This is used to constrain the lateral deviation of the belt, ensure the alignment accuracy of the belt during operation, and ensure the normal operation of the conveyor belt 420. Multiple roller sets 470 are also provided at the bottom of the belt, spaced apart along the conveying direction, to support the drooping section of the conveyor belt 420 and prevent excessive sagging due to its own weight or excessive load.

[0047] Furthermore, baffles 450 can be installed on both sides of the paint recycling mechanism 400. The baffles 450 are located on both sides of the spraying area to prevent the paint mist generated during the spraying process from spreading to both sides and to protect the cleanliness of the workshop environment.

[0048] Specifically, a paint recycling tray 510 is provided inside the frame 500. The paint recycling tray 510 is located below the spraying chamber assembly 200, and the recycled paint from the paint recycling mechanism 400 is collected in the paint recycling tray 510 through pipelines. A paint collection trough 511 is provided in the middle of the paint recycling tray 510. The paint collection trough 511 has an inclined trough structure, and an output port is provided at the bottom of the paint collection trough 511. The output port is connected to the external paint supply system of the paint equipment, thereby realizing the reuse of recycled paint.

[0049] Example 2: Please refer to Figures 7 to 9 In this embodiment, the spray booth 210 is also equipped with a pneumatic baffle mechanism 260. The pneumatic baffle mechanism 260 includes a cylinder 261 and a gear and rack transmission assembly 262 that is pulsatorically connected to the cylinder 261. The gear and rack transmission assembly 262 includes a rack driven by the cylinder 261 to perform linear motion and a gear meshing with the rack. The gear is connected to a baffle 263, and the baffle 263 moves between a shielding position and a retracted position under the drive of the cylinder 261 via the gear and rack transmission assembly 262. In the shielding position, the baffle 263 shields the spraying area of ​​the spray gun assembly 240.

[0050] Specifically, cylinder 261 is fixedly mounted on the outer wall or internal support of the spray booth 210, with its piston rod end fixedly connected to a rack. When cylinder 261 is energized, the piston rod pushes the rack to slide back and forth along a preset linear guide. Since the rack and gear remain in constant mesh, the linear displacement of the rack is precisely converted into the rotational motion of the gear, which in turn drives the baffle 263, which is coaxially fixed with the gear, to rotate around its axis. Compared with the multi-link mechanism or direct rotary cylinder used in traditional technologies, the gear and rack transmission assembly 262 has the advantages of compact structure, constant transmission ratio, and no accumulated backlash, making it particularly suitable for installation in areas with limited space inside the spray booth 210. At the same time, the gear and rack structure allows the installation position of cylinder 261 to be flexibly arranged away from the rotation axis of baffle 263, avoiding direct exposure of the actuator to the high temperature and high humidity core area of ​​the spraying process, thus extending the service life of the pneumatic components.

[0051] It should be noted that the pneumatic baffle mechanism 260 in this embodiment and the diversion and return mechanism in the previous embodiment are fundamentally different in function. They are complementary rather than substitutive. The diversion and return mechanism is the core fluid path switching device, responsible for cutting off the paint supply from the source and guiding it back to the raw material tank during shutdown or maintenance, solving the problems of pipeline residue and raw material waste; while the pneumatic baffle mechanism 260 is an auxiliary physical protection device, which is only activated under specific operating conditions.

[0052] Specifically, when the equipment is in normal spraying operation, the baffle 263 remains in the retracted position, completely avoiding the spray flow field of the spray gun assembly 240 and preventing interference with the atomizing fan. When the equipment is stopped or malfunctioning, the baffle 263 also remains in the retracted position and requires no action because the diversion and return mechanism has cut off the material supply. Only when online cleaning, backwashing, or paint formula change is required for the nozzles, will the operator control the cylinder 261 to rotate the baffle 263 to the shielding position, covering the spray opening area below the spray gun assembly 240. At this time, the baffle 263 acts as a temporary drip tray or shielding plate to prevent cleaning solvent, residual paint mist, or color change transition material from dripping and contaminating the conveying mechanism 100 or the collection tank below. This division of labor design completely abandons the technical approach of relying on physical gates at the nozzles for shutdown shielding in the first-generation machine, ensuring zero interference during normal production and meeting the anti-contamination requirements under special maintenance conditions.

[0053] Compared to existing technologies that use physical gates at the nozzle for shielding, the feed-end diversion and recirculation control strategy employed in this embodiment offers significant technical advantages. Physical gates only cut off paint spraying at the nozzle outlet, but the feed pump continues to pressurize the pipeline, resulting in a large amount of paint remaining in the spray gun body and the several-meter-long feed hose. This retained paint is highly susceptible to settling, solidification, or deterioration during shutdown, leading to material waste and contamination of the new coating upon restarting. This application, however, achieves a "zero residue" state for the spray gun and pipeline by switching the flow path and coordinating pressure control at the feed source. This cuts off the material supply to the spray gun immediately upon shutdown and actively draws back the residual paint in the pipeline. This significantly reduces the consumption of cleaning solvents and wastewater discharge, completely eliminates quality defects caused by paint deterioration, and significantly improves the continuous operation stability of the equipment and product yield.

[0054] Specifically, in this embodiment, the workflow of the spraying equipment includes: The system acquires operating status signals from the spraying equipment, including spraying operation signals, shutdown signals, and cleaning signals. Specifically, the controller, as the executor of the method, collects status feedback from various functional modules of the equipment in real time through its input interface. The spraying operation signal is typically triggered by the production line main control system or photoelectric sensors, indicating that a workpiece has entered the spraying area on the conveyor mechanism 100 and the spray gun assembly 240 is in a ready state. The shutdown signal can come from the emergency stop button, fault detection sensor or production interval timer, indicating that the equipment needs to immediately stop spraying or enter standby mode; The cleaning signal is manually triggered by the human-machine interface (HMI) or automatically generated according to the preset maintenance cycle, indicating that the spray gun and pipeline need to be solvent flushed or backflushed cleaned.

[0055] The target flow path is determined based on the type of operating status signal. Specifically, the controller has a pre-set status-flow path mapping logic table. When a spraying operation signal is detected, the target flow path is determined to be the spraying flow path connecting the material supply source and the spray gun assembly 240; when a stop signal or cleaning signal is detected, the target flow path is determined to be the return flow path connecting the material supply source and the return end. This determination process transforms discrete operating condition signals into explicit fluid control commands, ensuring the determinism of flow path switching. For example, in continuous production, if the equipment is briefly stopped due to an interruption in front-end material feeding, the controller immediately determines to switch to the return flow path after receiving the stop signal to prevent the paint from settling and solidifying in the stationary spray gun; and when material feeding resumes and the spraying operation signal is reactivated, it automatically determines to switch back to the spraying flow path, achieving seamless connection.

[0056] The controller sends a position control command to the servo motor, driving the valve core to rotate to a preset angle that matches the target flow path. When the target flow path is a spraying flow path, the servo motor drives the valve core to rotate to a first preset angle (e.g., 0°), precisely aligning the first flow channel inside the valve core with the first and second ports, establishing a smooth path from the material supply source to the spray gun assembly 240. When the target flow path is a return flow path, the servo motor drives the valve core to rotate to a second preset angle (e.g., 90°), aligning the second flow channel inside the valve core with the first and third ports, while physically blocking the passage to the spray gun assembly 240. Compared to traditional pneumatic valves, the closed-loop control characteristics of the servo motor ensure precise valve core angle positioning, avoiding internal leakage or abnormal flow resistance caused by insufficient valve core deflection, and ensuring the reliability and repeatability of flow path switching.

[0057] When the return flow path is activated, a pressure reduction command is simultaneously sent to the material supply source. Specifically, when the controller switches to the return flow path (or within a preset time window before the switch is completed), a pressure reduction control signal is sent to the feed pump inverter via analog output or communication bus to rapidly reduce the output pressure of the feeding system from the spraying working pressure (e.g., 2.0MPa-3.0MPa) to the circulation maintenance pressure (e.g., 0.3MPa-0.8MPa). This step is the key difference between the method of this application and the prior art. Its physical mechanism is as follows: if the switch to return flow is performed directly under high pressure, the high-pressure coating will generate violent turbulence and cavitation instantly because the back pressure of the return pipeline is much lower than the spraying load. This will not only cause erosion damage to the valve core sealing surface, but also form vortex dead angles at the pipeline bends, leading to coating deposition. More importantly, the high-pressure residual coating is very easy to drip from the spray gun nozzle or atomize and splash due to uneven pressure release after losing nozzle constraint. By simultaneously and actively reducing pressure, the coating can be smoothly and steadily flow back to the raw material tank in a laminar flow state, avoiding mechanical impact and noise. It also completely eliminates the residual pressure in the spray gun barrel, fundamentally preventing leakage and material waste during downtime.

[0058] Furthermore, in this embodiment, the specific gravity (density corresponding to Baumé) of the coating is 1.5-1.6 g / cm³. Coatings within this density range have high solid content and viscosity characteristics, allowing them to form a coating layer with a certain adhesion strength on the bottom surface of the conveyor belt 420 after spraying. Based on the adhesion ability of the coating layer, it can remain on the surface of the conveyor belt 420 for a certain period. A safe time for the coating layer to adhere to the conveyor belt 420 can be set according to the conveying speed of the conveyor belt 420 and parameters such as the temperature and humidity of the working environment. During this safe time, the conveyor belt 420 is activated to rotate and recover the coating. The scraping mechanism at the top of the conveyor belt 420 can facilitate the recovery of any remaining coating material adhering to the surface of the conveyor belt 420, thereby preventing the coating from contaminating the product. This also enables an independent driving system between the conveyor belt 420 and the conveying mechanism, improving the overall working efficiency and coordinated control capabilities of the machine.

[0059] The spraying system provided in this embodiment integrates independent spraying equipment with an external paint supply unit into a complete fluid handling closed loop. The supply source can be a mobile raw material tank, a fixed paint storage tank, or a centralized supply station, used to store and continuously supply paint media to the spraying equipment. The connecting pipelines include a main supply pipeline and a return pipeline, respectively handling the forward delivery and reverse recovery of paint. This system-level integrated design not only clarifies the boundary conditions of the spraying equipment in practical applications but also effectively prevents competitors from circumventing infringement risks by selling spraying units without a supply source separately, ensuring patent protection covers the entire industry chain from single units to complete systems.

[0060] In this embodiment, the return end of the diversion and return mechanism is physically connected to the return port of the material supply source through a return pipeline, forming a paint circulation loop. Specifically, one end of the return pipeline is sealed and connected to the third port of the switching valve assembly, and the other end extends below the liquid level inside the material supply source or connects to a dedicated return buffer chamber, thereby constructing a closed fluid channel that starts from the material supply source, bypasses the diversion and return mechanism, and returns to the material supply source. When the system is in shutdown or cleaning mode, the diversion and return mechanism cuts off the flow path to the spray gun assembly 240, and at the same time directly introduces the paint output from the material supply source into the circulation loop.

[0061] Furthermore, in the production line layout, this spraying system is typically located between the pretreatment process and the curing process, and achieves continuous workpiece flow with upstream and downstream equipment via the conveying mechanism 100. Specifically, in actual production, the material supply source is often placed in a safe area beside the spraying equipment or in a dedicated paint mixing room, connected to the spraying host via overhead or underground pipeline corridors. This layout not only meets fire and explosion safety regulations but also shortens the length of the material supply pipeline, reducing pipeline pressure loss and paint retention volume. More importantly, thanks to the synergistic effect of the diversion and return mechanism and the controller in the aforementioned embodiment, the system achieves zero-residue circulation of paint between the material supply source and the spraying equipment. Compared to traditional open spraying systems or semi-closed systems that rely solely on nozzle shielding, the spraying system provided in this application completes flow path switching and pressure unloading the instant the machine stops, allowing all residual paint in the pipeline to return to the material source and participate in the next cycle. This completely eliminates the waste of raw materials caused by paint curing and becoming unusable in the pipeline, while also avoiding the environmental treatment costs associated with waste solvent discharge, significantly improving the economic efficiency and green manufacturing level of the entire production line.

[0062] Furthermore, the embodiments of the present invention have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A spraying device, characterized in that, The spraying equipment includes: a body, a spraying chamber assembly disposed within the body, and a conveying mechanism disposed on the body; The conveying mechanism is used to convey the target workpiece; The spraying chamber assembly is located below the conveying mechanism. The spraying chamber assembly includes an integrated and fixedly connected spraying cabinet and a guide trough. The spraying cabinet is provided with a sliding guide structure. The spray gun assembly is removably installed in the spraying cabinet through the sliding guide structure. The spray gun assembly switches between a spraying position inside the spraying cabinet and a maintenance position at least partially removed from the spraying cabinet based on the sliding guide structure.

2. The spraying equipment as described in claim 1, characterized in that, The sliding guide structure includes a guide rail disposed on the inner wall of the spray booth and a slider disposed on the bottom of the spray gun assembly. The slider slides in cooperation with the guide rail so that the spray gun assembly can move along the guide rail between the spraying position and the maintenance position.

3. The spraying equipment as described in claim 2, characterized in that, The spray gun assembly includes a pipe, multiple nozzles, and a mounting plate. The multiple nozzles are distributed along the length of the pipe. One end of the pipe is fixed to the mounting plate, and the bottom of the mounting plate is provided with the slider.

4. The spraying equipment as described in claim 1, characterized in that, One end of the spray gun assembly is fastened to the end of the spray booth by a fastener, and the end of the spray booth has an opening through which the spray gun assembly passes; when the fastener is loosened, the spray gun assembly can be pulled out along the opening to the maintenance position.

5. The spraying equipment as described in claim 1, characterized in that, The spray booth is also equipped with a pneumatic baffle mechanism, which includes a cylinder and a gear and rack transmission assembly that is pulsatorically connected to the cylinder. The gear and rack transmission assembly includes a rack driven by the cylinder to perform linear motion and a gear meshing with the rack. The gear is connected to the baffle, and the baffle switches between the blocking position and the retracted position through the gear and rack transmission assembly under the drive of the cylinder. At the shielding position, the baffle shields the spraying area of ​​the spray gun assembly.

6. The spraying equipment as described in claim 1, characterized in that, The spraying equipment also includes a diversion and return mechanism disposed in the paint pipeline. The diversion and return mechanism includes a switching valve assembly, which has a first port, a second port and a third port. The first port is connected to the material supply source, the second port is connected to the spray gun assembly, and the third port is connected to the return end. In the spraying flow path, the first port is connected to the second port; in the return flow path, the first port is connected to the third port.

7. The spraying equipment as described in claim 6, characterized in that, The switching valve assembly is a three-way valve assembly, and the three-way valve assembly is internally provided with a valve core and a power component for driving the valve core to rotate; The valve core has a first flow channel connecting the first port and the second port, and a second flow channel connecting the first port and the third port.

8. The spraying equipment as described in claim 1, characterized in that, The conveying mechanism includes a conveyor belt and water-blocking strips disposed on both sides of the conveyor belt, the water-blocking strips extending along the conveying direction of the conveyor belt.

9. The spraying equipment as described in claim 1, characterized in that, The conveying mechanism is provided with an integrated through-type material collection trough below it. The integrated through-type material collection trough extends along the conveying direction of the conveying mechanism, and the opening of the integrated through-type material collection trough faces the conveying mechanism.

10. The spraying equipment as described in claim 1, characterized in that, The conveying mechanism includes multiple rollers, a first drive motor, and a transmission mechanism. The multiple rollers are arranged inside the transmission mechanism. The output shaft of the first drive motor is connected to the transmission mechanism, and the first drive motor drives the multiple rollers based on the transmission mechanism.

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