A high-precision surface spraying device

Abstract

The application relates to the field of spraying technology and discloses a high-precision surface spraying device, which comprises a spraying cabinet body and a liquid adding cabinet. A pressure bucket one is fixedly arranged in the spraying cabinet body. A spraying mechanism is arranged on the upper portion of the spraying cabinet body. The spraying mechanism is connected with the pressure bucket one through a pipeline. A pressure bucket two is fixedly arranged on the upper surface of the liquid adding cabinet. The pressure bucket two is connected with the pressure bucket one through a liquid supplementing pipeline. The pressure bucket two is independently arranged as a large-capacity liquid supplementing storage tank and is connected with the pressure bucket one, so that the liquid supplementing and the spraying operation are separated in space. The rotation mechanism of one bucket for supplying liquid and one bucket for supplementing liquid eliminates the time window of forced shutdown caused by adding liquid, avoids the flow fluctuation of the initial section of the spray head and the surface scratch defects of a workpiece caused by shutdown and restart, and guarantees the continuous operation of a production line.

Description

Technical Field

[0001] This invention relates to the field of spraying technology, specifically to a high-precision surface spraying device. Background Technology

[0002] Surface spraying is a widely used surface treatment process in manufacturing, involving the uniform application of coatings, inks, or functional solutions to flat workpieces such as glass, metal plates, and plastic sheets. Existing spraying equipment typically uses a closed spray cabinet, with a pressure tank inside to store the solution. Compressed air drives the solution through pipelines to the nozzles for atomized spraying. It is also equipped with conveyor rollers and heating devices to complete the continuous processing of workpieces.

[0003] However, existing spraying equipment has a limited pressure tank capacity, typically 5 to 10 liters. When the liquid in the tank is depleted, the machine must be stopped to replenish it. The replenishment process requires shutting off the compressed air, releasing residual pressure in the tank, opening the tank lid, manually injecting the liquid, resealing, and pressurizing to the set value. The entire process usually takes 3 to 10 minutes. During this time, the production line is forced to stop, and the spraying mechanism, conveyor rollers, and heating chamber all need to be stopped or repeatedly started and stopped. This shutdown and replenishment method directly reduces production capacity, and the losses are particularly significant in high-cycle continuous production scenarios. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a high-precision surface spraying device that solves the problem of limited pressure tank volume in existing spraying devices and the direct reduction in production capacity caused by the aforementioned shutdown and liquid replenishment methods.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a high-precision surface spraying device, comprising a spraying cabinet and a liquid filling cabinet, wherein a pressure tank is fixedly installed inside the spraying cabinet, and a spraying mechanism is provided in the upper part of the spraying cabinet, the spraying mechanism being connected to the pressure tank through a pipeline; a pressure tank is fixedly installed on the upper surface of the liquid filling cabinet, and the pressure tank is connected to the pressure tank through a liquid replenishment pipeline.

[0006] Preferably, the spraying mechanism includes an electric slide rail and a spray head. The electric slide rail is fixedly installed inside the spraying cabinet, the spray head is slidably disposed on the electric slide rail, and the spray head is connected to the pressure tank through a pipeline.

[0007] Preferably, the interior of the spraying cabinet is equipped with conveyor rollers.

[0008] Preferably, a heating chamber is fixedly installed inside the spraying cabinet, and the heating chamber is located above the conveyor rollers.

[0009] Preferably, a pressure regulating valve is also fixedly installed inside the spraying cabinet, and the pressure regulating valve is installed on the air inlet pipe of the pressure tank.

[0010] Preferably, it also includes a liquid level sensor, which is disposed on the pressure tank and is used to detect the liquid level inside the pressure tank.

[0011] Preferably, it further includes an electronically controlled proportional pressure regulating valve two and a controller. The electronically controlled proportional pressure regulating valve two is installed on the air inlet pipe of the pressure tank one. The controller is electrically connected to the liquid level sensor and the electronically controlled proportional pressure regulating valve two respectively. The controller is configured to adjust the output pressure of the electronically controlled proportional pressure regulating valve two according to the liquid level height to compensate for the static pressure change caused by the change in liquid level height.

[0012] Preferably, a damping cavity is connected in series in the connecting pipe between the nozzle and the pressure tank.

[0013] Preferably, the damping cavity includes a bellows section and a piezoelectric vibrator, wherein the bellows section is pre-filled with gas, and the piezoelectric vibrator is attached to the cavity wall of the bellows section.

[0014] Preferably, it further includes a pressure sensor and a vibration controller. The pressure sensor is used to detect pressure pulsations in the connecting pipeline. The vibration controller is electrically connected to the pressure sensor and the piezoelectric vibrator. The vibration controller is configured to drive the piezoelectric vibrator to generate anti-phase vibration according to the detected pressure pulsations, so as to actively eliminate the pressure pulsations.

[0015] This invention provides a high-precision surface spraying device. It has the following beneficial effects:

[0016] 1. This invention uses pressure tank two as a large-capacity replenishment tank, independently arranged, and connected to pressure tank one via a one-way valve and a solenoid valve, achieving spatial separation between liquid replenishment and spraying operations. The alternating mechanism of supplying one tank and replenishing the other eliminates the time window of forced shutdown due to liquid addition, avoids initial flow fluctuations in the nozzle and defects on the workpiece surface caused by restarting after a shutdown, and ensures continuous operation of the production line.

[0017] 2. This invention uses a capacitive liquid level sensor to collect the liquid level height in pressure tank one in real time. The controller drives the electronically controlled proportional pressure regulating valve two to dynamically adjust the intake pressure based on the change in static pressure of the liquid column. A compensation amount is added on the set reference value to offset the static pressure loss caused by the drop in liquid level. At the same time, the pressure is quickly reduced when the liquid level rises sharply during the replenishment process to prevent pressure overshoot. This ensures that the atomization flow rate and spray pattern are consistent, fundamentally solving the industry problem of pressure decay with liquid level in high-level liquid supply scenarios.

[0018] 3. This invention incorporates a damping cavity in series in the connecting pipe between the nozzle and the pressure tank, passively absorbing high-frequency pressure pulsations using the compressibility of pre-placed gas within the corrugated pipe section. Furthermore, a pressure sensor collects the pipe pulsation signal in real time, and a vibration controller drives a piezoelectric vibrator to generate an anti-phase pressure wave, actively counteracting residual pulsations caused by the compressor's periodic exhaust and the surge of the pressure regulating valve's diaphragm. This synergistic passive and active approach ensures extremely high stability of the liquid pressure entering the nozzle, significantly improving the microscopic uniformity of the coating thickness and the surface treatment quality of the workpiece. Attached Figure Description

[0019] Figure 1 This is a perspective view of the present invention;

[0020] Figure 2 This is a partial structural diagram of the pressure tank of the present invention;

[0021] Figure 3 This is a cross-sectional schematic diagram of the internal structure of the spraying cabinet of the present invention;

[0022] Figure 4 This is a partial structural diagram of the pressure regulating valve of the present invention;

[0023] Figure 5 This is a control diagram of the present invention.

[0024] The components include: 1. Spraying cabinet; 2. Pressure tank one; 3. Spraying mechanism; 301. Electric slide rail; 302. Spray nozzle; 4. Conveying roller; 5. Heating chamber; 6. Liquid filling cabinet; 7. Pressure tank two; 8. Pressure regulating valve one. Detailed Implementation

[0025] The technical solution of the present invention will now be clearly and completely described 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.

[0026] Currently, conventional spray coating machines on the market use simple small pressure tanks for pneumatic liquid supply. This supply method has many insurmountable technical defects, severely restricting the precision and stability of the surface spraying process. Inaccurate flow control leads to uneven surface coating, with significant differences in coating thickness across different areas of the workpiece. Some areas have excessively thick coatings causing sagging, while others have insufficient coatings to meet protective or decorative requirements. Continuous replenishment of the coating solution is impossible; when the solution in the small pressure tank is depleted, the machine must be stopped for replenishment, interrupting continuous production and significantly reducing efficiency. Frequent start-stop operations also cause fluctuations in spraying parameters, affecting the consistency of batches of workpieces. Subsequent use of the surface treatment is unsatisfactory; uneven coatings are prone to localized peeling and accelerated corrosion during use, shortening the workpiece's lifespan. Waste of processing solution is also a problem; inaccurate flow control and solution residue during replenishment after shutdowns result in unnecessary consumption of a large amount of solution, increasing production costs.

[0027] Please see the appendix Figure 1 -Appendix Figure 5 This invention provides a high-precision surface spraying device, including a spraying cabinet 1 and a liquid filling cabinet 6. A pressure tank 2 is fixedly installed inside the spraying cabinet 1, and a spraying mechanism 3 is provided in the upper part of the spraying cabinet 1. The spraying mechanism 3 is connected to the pressure tank 2 by a pipeline. A pressure tank 7 is fixedly installed on the upper surface of the liquid filling cabinet 6. The pressure tank 7 is connected to the pressure tank 2 by a liquid replenishment pipeline.

[0028] Specifically, the spray booth 1 is a closed box structure. Inside the spray booth 1, a pressure tank 2 is fixedly installed. This pressure tank 2 is a small pressure vessel with a volume of 5 liters, used to hold the spraying solution. A spraying mechanism 3 is located at the upper part of the spray booth 1. The spraying mechanism 3 is connected to the pressure tank 2 via a flexible pressure-resistant pipeline. The spraying solution in the pressure tank 2 is driven by compressed air and transported along the pipeline to the spraying mechanism 3 for atomized spraying. The replenishment cabinet 6 is arranged independently of the spray booth 1. A pressure tank 7, a large-capacity pressure tank with a volume of 10 liters, is fixedly installed on the upper surface of the replenishment cabinet 6, serving as a replenishment tank. The pressure tank 7 is connected to the pressure tank 2 via a replenishment pipeline equipped with a one-way valve and a solenoid valve to ensure that the spraying solution can only flow unidirectionally from the pressure tank 7 to the pressure tank 2. This configuration spatially separates the spraying operation from the replenishment of the spraying solution, providing a structural basis for continuous replenishment without shutting down the machine. The top of pressure tank 2 (7) is equipped with a liquid inlet, a compressed air inlet, and a safety pressure relief valve. Pre-mixed chemical solution is manually injected into pressure tank 2 (7) through the liquid inlet. The inlet is then closed, and clean compressed air is introduced to pressurize the solution to the set value. The air pressure inside pressure tank 2 (7) is maintained within the range of 0.3 MPa to 0.4 MPa, providing a stable driving force for liquid replenishment. When the liquid level in pressure tank 1 (2) drops to the liquid replenishment trigger level, the control system opens the solenoid valve on the liquid replenishment pipeline. The chemical solution in pressure tank 2 (7) is then forced into pressure tank 1 (2) under air pressure. This configuration, with one pressure tank 2 (7) corresponding to two pressure tanks 1 (2), allows one pressure tank 1 (2) to serve as a backup or be replenished while one is performing spraying liquid supply. The valve switching ensures uninterrupted liquid supply, eliminating the time window of forced shutdown due to adding chemical solution. This dual-tank rotation liquid replenishment mechanism not only ensures continuous operation of the production line but also avoids initial flow fluctuations in the nozzle and defects such as workpiece surface seams caused by restarting after a shutdown.

[0029] The spraying mechanism 3 includes an electric slide rail 301 and a spray head 302. The electric slide rail 301 is fixedly installed inside the spraying cabinet 1, and the spray head 302 is slidably mounted on the electric slide rail 301. The spray head 302 is connected to the pressure tank 2 through a pipeline.

[0030] Specifically, the spraying mechanism 3 includes an electric slide rail 301 and a nozzle 302. The electric slide rail 301 is fixedly installed below the inner top wall of the spraying cabinet 1, and the slider is driven by a servo motor via a synchronous belt or ball screw. The nozzle 302 is slidably mounted on the slider of the electric slide rail 301 via a connecting bracket, and moves reciprocating linearly above the spraying area with the slider. The nozzle 302 is an air-assisted atomizing nozzle with a liquid channel in the center and a compressed air annular gap in the outer ring. By adjusting the atomizing air pressure and liquid flow rate, a uniform fan-shaped spray pattern can be obtained. The nozzle 302 is connected to the outlet of the pressure tank 2 via a 4 mm inner diameter polytetrafluoroethylene hose, and a precision filter is connected in series in the pipeline to prevent particles from clogging the nozzle.

[0031] The interior of the spray painting cabinet 1 is equipped with conveyor rollers 4.

[0032] Specifically, the interior of the spray booth 1 is equipped with conveyor rollers 4. These conveyor rollers 4 are arranged horizontally to form a roller conveyor line, located directly below the spraying mechanism 3, with their axis perpendicular to the sliding direction of the electric slide rail 301. The conveyor rollers 4 are driven by a geared motor equipped with a frequency converter. During operation, flat workpieces to be sprayed, such as glass, metal plates, or plastic sheets, are fed into the spray booth 1 through the inlet, smoothly supported and conveyed forward by the conveyor rollers 4, and then subjected to reciprocating scanning spraying by the nozzles 302 as they pass through the spraying area.

[0033] A heating chamber 5 is fixedly installed inside the spraying cabinet 1, and the heating chamber 5 is located above the conveyor roller 4.

[0034] Specifically, a heating chamber 5 is fixedly installed inside the spraying cabinet 1. The heating chamber 5 is located above the conveyor rollers 4 and downstream of the spraying mechanism 3. The outer shell of the heating chamber 5 is made of stainless steel plate, and multiple mid-wave infrared radiation tubes or armored heating wires are arranged inside. A reflector is installed on the back to concentrate the heat radiation onto the workpiece surface. The heating chamber 5 is equipped with thermocouple temperature sensors and a temperature control module, which can control the air temperature or radiation plate temperature inside the chamber within the range of 40 degrees Celsius to 0 degrees Celsius, with an accuracy of ±2 degrees Celsius. Between multiple spraying processes, the heating chamber 5 preheats the freshly sprayed wet film at a low temperature, promoting solvent evaporation and initial curing of the coating, avoiding sagging and improving interlayer adhesion. When the spraying process is a two-component or reactive solution, the heating chamber 5 can activate the cross-linking reaction, improving the coating hardness and chemical resistance.

[0035] The spraying cabinet 1 is also equipped with a pressure regulating valve 8, which is located on the air inlet pipe of the pressure tank 2.

[0036] Specifically, a pressure regulating valve 8 is fixedly installed inside the spray booth 1, and is located on the air inlet pipe of the pressure tank 2. The pressure regulating valve 8 is a high-precision diaphragm-type mechanical pressure reducing valve. Its primary side is connected to the factory's compressed air network. After being filtered to remove water and oil by the air source treatment unit, the air enters the pressure regulating valve 8. The operator sets the secondary side output pressure by rotating the adjustment knob and directly reads the output air pressure value through the pressure gauge integrated on the valve body; the typical setting value is 0.25 MPa. The pressure regulating valve 8 provides a stable air source pressure for the pressure tank 2 and is the fundamental pressure setting link of the entire pneumatic liquid supply system. However, since the pressure tank 2 is supplied with liquid at a high level, changes in liquid level will cause changes in the static pressure of the liquid column. The constant pressure of the pressure regulating valve 8 alone cannot guarantee a constant effective pressure at the nozzle. Therefore, subsequent liquid level detection and electronic proportional compensation links are required to work together to achieve high-precision pressure control.

[0037] It also includes a liquid level sensor, which is installed on pressure tank 2 to detect the liquid level inside pressure tank 2.

[0038] Specifically, a liquid level sensor is installed on the side wall or top cover of pressure tank 2. The liquid level sensor detects the liquid level inside pressure tank 2, with a measurement range covering the lowest working liquid level to the highest liquid level. The liquid level sensor is a capacitive type, with its sensing electrode strip closely attached to the outer wall of pressure tank 2, sensing the difference in dielectric constant between the liquid and air in a non-contact manner to achieve continuous liquid level detection. This method avoids contact with the liquid, preventing sensor contamination and corrosion, and is suitable for liquid systems containing organic solvents. Another optional solution is to seal a magnetostrictive liquid level probe on the top of pressure tank 2. Its float floats with the liquid level, and the waveguide wire inside the probe converts the liquid level signal into a high-precision electrical signal. The liquid level sensor outputs an analog or digital signal, sending the liquid level height value h to the controller in real time, providing a direct data source for subsequent hydrostatic compensation calculations.

[0039] It also includes an electronically controlled proportional pressure regulating valve II and a controller. The electronically controlled proportional pressure regulating valve II is installed on the air inlet pipe of pressure tank 2. The controller is electrically connected to the liquid level sensor and the electronically controlled proportional pressure regulating valve II respectively. The controller is configured to adjust the output pressure of the electronically controlled proportional pressure regulating valve II according to the liquid level height to compensate for the static pressure change caused by the change in liquid level height.

[0040] Specifically, the high-precision surface spraying equipment also includes an electronically controlled proportional pressure regulating valve II and a controller. The electronically controlled proportional pressure regulating valve II is connected in series in the air inlet pipe of pressure tank 2, located downstream of pressure regulating valve 8 or directly replacing pressure regulating valve 8. The electronically controlled proportional pressure regulating valve II is an electronically proportional control type precision pressure regulating valve, containing an internal pressure sensor feedback closed loop with a resolution of up to 0.001 MPa and a response time within 50 milliseconds, capable of precisely adjusting the output air pressure based on the input analog control signal. The controller is electrically connected to both the liquid level sensor and the electronically controlled proportional pressure regulating valve II. The controller can be a programmable logic controller (PLC) or an embedded industrial control motherboard. The controller has a pre-set compensation algorithm, the core principle of which is: the effective liquid pressure at the inlet of nozzle 302 equals the air pressure inside pressure tank 2 plus the static pressure of the liquid column minus the pipeline pressure loss. The controller calculates ΔP based on the real-time liquid level height h provided by the liquid level sensor, and then outputs an increase signal corresponding to ΔP to the electronically controlled proportional pressure regulating valve 2. This causes the intake pressure to be superimposed on the set reference value by ΔP to compensate for the static pressure loss due to the liquid level drop. In this way, regardless of the liquid level change, the effective pressure at nozzle 302 remains constant, thus ensuring consistent flow rate and atomization characteristics. When the liquid level rises sharply during the replenishment process of pressure tank 2, the controller quickly reduces the output air pressure of the electronically controlled proportional pressure regulating valve 2 to prevent pressure overshoot and effectively smooth out pressure jumps caused by liquid replenishment switching.

[0041] A damping cavity is connected in series in the connecting pipe between the nozzle 302 and the pressure tank 2.

[0042] Specifically, a damping cavity is connected in series in the connecting pipe between nozzle 302 and pressure tank 2. The inlet and outlet of the damping cavity are sealed to the upstream and downstream pipes respectively, and are integrated into the liquid flow channel as a whole. The main body of the damping cavity is a small cylindrical or spherical stainless steel cavity with an internal volume of 20 ml to 50 ml. The cavity is filled with a certain amount of liquid medicine, and an air chamber is separated in the upper space of the cavity or by an elastic element. The damping cavity uses the compressibility of gas to form an air cushion effect, which can passively absorb high-frequency pressure pulsations in the pipeline, just like an accumulator in a hydraulic system, attenuating the amplitude of the pulsations. After the damping cavity is set, the pressure peaks originally caused by the air pressure fluctuations in the pressure tank and the pressure regulating element are significantly smoothed, and the instantaneous flow of nozzle 302 is more stable. To achieve a higher degree of pulsation suppression, the damping cavity further integrates an active vibration damping structure to actively cancel residual pulsations.

[0043] The damping cavity includes a bellows section and a piezoelectric vibrator. Gas is pre-filled inside the bellows section, and the piezoelectric vibrator is attached to the cavity wall of the bellows section.

[0044] Specifically, the damping cavity comprises a bellows section and a piezoelectric vibrator. The bellows section is a stretchable bellows made of thin-walled polytetrafluoroethylene (PTFE) or stainless steel, coaxially integrated within the damping cavity or forming part of it. A certain volume of inert gas, such as nitrogen or clean air, is pre-filled inside the bellows section at a pressure slightly lower than the normal operating pressure of the pipeline, keeping it in a compressible state. The piezoelectric vibrator is a piezoelectric ceramic bicrystalline wafer or a piezoelectric composite material vibrator, attached to the outer wall of the bellows section using epoxy resin or mechanical clamping. When an alternating voltage is applied to the piezoelectric vibrator, it undergoes bending deformation, which in turn causes the bellows section to expand and contract at the micrometer level, changing the gas volume inside the bellows and thus generating a pressure wave in the liquid within the damping cavity. By precisely controlling the movement of the piezoelectric vibrator, a controllable compensating pressure wave can be generated within the damping cavity.

[0045] It also includes a pressure sensor and a vibration controller. The pressure sensor is used to detect pressure pulsations in the connecting pipeline. The vibration controller is electrically connected to the pressure sensor and the piezoelectric vibrator. The vibration controller is configured to drive the piezoelectric vibrator to generate anti-phase vibration according to the detected pressure pulsations in order to actively eliminate the pressure pulsations.

[0046] Specifically, the spraying equipment also includes a pressure sensor and a vibration controller. The pressure sensor is a piezoelectric thin-film dynamic pressure sensor, installed on the connecting pipe upstream of the damping cavity, with the sensing surface directly contacting the liquid coating to detect pressure pulsations within the pipe. The output signal of the pressure sensor contains the frequency, amplitude, and phase information of the pulsations, with a signal bandwidth reaching several kilohertz. The vibration controller is electrically connected to the pressure sensor and the piezoelectric vibrator, forming an adaptive feedforward-feedback control system. The vibration controller includes a signal conditioning circuit, an analog-to-digital converter, a digital signal processor, and a power amplifier. Its working process is as follows: the pressure sensor acquires the pipe pressure pulsation signal, which is then converted from analog to digital. The digital signal processor uses a fast Fourier transform or an adaptive notch filter algorithm to extract the main pulsation frequency component in real time and analyze its phase. Based on the extracted pulsation characteristics, the vibration controller generates a control signal with the same frequency, matched amplitude, and opposite phase as the original pulsation signal. After power amplification, this signal drives the piezoelectric vibrator to produce anti-phase vibration. When excited, the corrugated pipe section radiates a pressure wave 180 degrees out of phase with the main pulsating wave into the liquid. The two waves superimpose and cancel each other out within the pipe, thus actively eliminating pressure pulsation. This active damping mechanism can significantly attenuate periodic pressure fluctuations caused by compressor cycle discharge, pressure regulating valve diaphragm surge, etc., resulting in extremely high stability of the liquid pressure entering the nozzle 302, ultimately improving the microscopic uniformity of the coating thickness and the surface treatment quality.

[0047] Workflow: The operator injects the pre-mixed solution into pressure tank 7 (10L) on the filling cabinet 6 through the filling port. After closing the port, clean compressed air is introduced to stabilize the pressure inside the tank at 0.3-0.4MPa. Pressure tank 7, as a replenishment tank, is arranged independently from the spraying cabinet 1. It is connected to pressure tank 2 (5L) inside the spraying cabinet 1 via a replenishment pipeline equipped with a check valve and a solenoid valve, ensuring that the solution can only flow in in one direction. The system adopts a "one large tank for two small tanks" dual-tank rotation strategy—when one pressure tank 2 is performing spraying solution supply, the other can be replenished simultaneously or used as a backup. Continuous solution supply without stopping the machine is achieved by switching valves.

[0048] During the spraying operation: The liquid in pressure tank 2 is transported to nozzle 302 via pipeline driven by compressed air (set to a base air pressure of 0.25MPa via pressure regulating valve 8). Nozzle 302 is mounted on the slider of electric slide rail 301 and is driven by a servo motor to perform reciprocating linear motion, scanning and atomizing the workpiece that passes smoothly on the conveying roller 4 below. During the spraying process, the controller reads the liquid level height data from the liquid level sensor in real time, calculates the static pressure loss ΔP caused by the drop in liquid level, and then outputs a compensation signal to the electronically controlled proportional pressure regulating valve 2, so that the air inlet pressure is superimposed on the reference value by ΔP, ensuring that the effective pressure at the inlet of nozzle 302 is constant. When liquid replenishment is triggered, the liquid level rises sharply, and the controller quickly reduces the air inlet pressure to prevent pressure overshoot.

[0049] Pulsation suppression and heat curing stage: Before reaching the nozzle 302, the liquid coating passes through a damping chamber connected in series in the pipeline. The damping chamber utilizes the compressibility of the pre-filled gas in the internal corrugated section to passively absorb high-frequency pressure pulsations. Simultaneously, a pressure sensor collects pipeline pressure fluctuation signals in real time. The excitation controller extracts the frequency and phase of the pulsations through digital signal processing, driving a piezoelectric vibrator attached to the outer wall of the corrugated pipe to generate anti-phase vibration, actively canceling residual periodic pulsations and ensuring relatively stable liquid pressure entering the nozzle 302. The wet film workpiece after spraying then enters the downstream heating chamber 5, where it undergoes low-temperature preheating under infrared radiation heat at 40–0℃, promoting solvent evaporation and initial coating curing, preventing sagging, and improving interlayer adhesion. The entire process, from liquid addition, spraying, pressure compensation to pulsation elimination and heat curing, forms a closed loop, achieving high-precision, non-stop continuous surface spraying.

[0050] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-precision surface spraying device, comprising a spraying cabinet (1) and a liquid filling cabinet (6), characterized in that: The spraying cabinet (1) has a pressure tank (2) fixedly installed inside. The upper part of the spraying cabinet (1) is provided with a spraying mechanism (3), which is connected to the pressure tank (2) by a pipeline. The upper surface of the liquid filling cabinet (6) has a pressure tank (7) fixedly installed on it, which is connected to the pressure tank (2) by a liquid replenishment pipeline.

2. The high-precision surface spraying equipment according to claim 1, characterized in that, The spraying mechanism (3) includes an electric slide rail (301) and a nozzle (302). The electric slide rail (301) is fixedly installed inside the spraying cabinet (1). The nozzle (302) is slidably disposed on the electric slide rail (301) and is connected to the pressure tank (2) through a pipeline.

3. The high-precision surface spraying equipment according to claim 1, characterized in that, The spraying cabinet (1) is equipped with conveyor rollers (4).

4. The high-precision surface spraying equipment according to claim 1, characterized in that, A heating chamber (5) is fixedly installed inside the spraying cabinet (1), and the heating chamber (5) is located above the conveying roller (4).

5. The high-precision surface spraying equipment according to claim 1, characterized in that: The spraying cabinet (1) is also fixedly equipped with a pressure regulating valve (8), which is located on the air inlet pipe of the pressure tank (2).

6. The high-precision surface spraying equipment according to any one of claims 1 to 5, characterized in that: It also includes a liquid level sensor, which is installed on the pressure tank (2) and is used to detect the liquid level inside the pressure tank (2).

7. The high-precision surface spraying equipment according to claim 6, characterized in that: It also includes an electronically controlled proportional pressure regulating valve II and a controller. The electronically controlled proportional pressure regulating valve II is installed on the air inlet pipe of the pressure tank I (2). The controller is electrically connected to the liquid level sensor and the electronically controlled proportional pressure regulating valve II respectively. The controller is configured to adjust the output pressure of the electronically controlled proportional pressure regulating valve II according to the liquid level height to compensate for the static pressure change caused by the change in liquid level height.

8. The high-precision surface spraying equipment according to claim 7, characterized in that: A damping cavity is connected in series in the connecting pipe between the nozzle (302) and the pressure tank (2).

9. The high-precision surface spraying equipment according to claim 8, characterized in that: The damping cavity includes a bellows section and a piezoelectric vibrator. Gas is pre-filled inside the bellows section, and the piezoelectric vibrator is attached to the cavity wall of the bellows section.

10. The high-precision surface spraying equipment according to claim 9, characterized in that: It also includes a pressure sensor and a vibration controller. The pressure sensor is used to detect pressure pulsations in the connecting pipeline. The vibration controller is electrically connected to the pressure sensor and the piezoelectric vibrator. The vibration controller is configured to drive the piezoelectric vibrator to generate anti-phase vibration according to the detected pressure pulsations, so as to actively eliminate the pressure pulsations.

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