Plastic part xenon lamp aging machine with spraying system

Abstract

The invention discloses a plastic part xenon lamp aging machine with a spraying system, and belongs to the technical field of material weather resistance testing equipment. The equipment comprises an aging chamber, a xenon lamp light source and a spraying system, and the spraying system realizes flexible switching spraying of pure water and a chemical solution through cooperative operation of a liquid supply unit (comprising double liquid storage tanks and a four-way switching valve), a nozzle unit (a multidirectional adjustable nozzle), a liquid recovery device (a collecting tank and a recovery pump) and a control unit. The control unit accurately controls the concentration and flow of the mixed solution by adjusting the opening degree of the flow valve, residual liquid is emptied through the four-way valve and the liquid drainage pipeline to avoid cross contamination, the spraying angle is dynamically adjusted through the multi-directional nozzle to ensure uniform coverage, and the recycling device recycles waste liquid in a classified mode to reduce resource consumption. The problems of single spraying mode, residual liquid pollution, uneven coverage and low waste liquid treatment efficiency of traditional equipment are solved, and the aging test accuracy, the environment simulation authenticity and the resource utilization rate are remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of material weathering test equipment, and more particularly to a xenon lamp aging machine for plastic parts with a spray system. Background Technology

[0002] Plastic products used outdoors are exposed to complex environments such as sunlight, rain, and chemicals for extended periods, making them prone to aging phenomena such as fading, embrittlement, and cracking. To assess the weather resistance of plastic parts, xenon lamp aging test equipment is widely used in laboratory accelerated aging tests. It uses a xenon lamp light source to simulate the solar spectrum, combined with a spray system to simulate the erosion of rainwater or chemical liquids.

[0003] Currently, such equipment has many limitations in its spraying function. Most devices only support single-liquid spraying (such as pure water). If switching to a chemical solution (such as acid rain simulation solution) is required, the storage tank must be manually replaced and the pipeline cleaned, which is cumbersome and results in long test interruptions. Although some devices support dual-liquid supply, they lack precise concentration control mechanisms, making it difficult to ensure the stability of the mixing ratio for low-concentration solutions (such as <1% detergent). When switching spraying liquid types, residual liquid from the previous liquid in the valves and pipelines can contaminate the new liquid. For example, residual chemical solutions can contaminate the subsequent pure water spraying system, leading to distorted test conditions. Existing equipment usually relies on manual rinsing or the addition of redundant pipelines; the former is inefficient, while the latter increases equipment complexity and cost. Fixed-angle nozzles are difficult to adapt to the layout of plastic parts of different shapes and sizes, easily creating spray blind spots or overlapping areas. Especially for complex automotive interior parts or electronic housings, insufficient contact with the liquid in certain areas can cause test results to deviate from the actual usage scenario. The sprayed liquid is often directly discharged, which not only increases the burden of wastewater treatment but also wastes deionized water and chemical reagents. A few devices are equipped with recycling tanks, but they do not distinguish between liquid types (such as pure water mixed with corrosive solutions), resulting in the contamination of reusable pure water, making it impossible to recycle.

[0004] Therefore, there is an urgent need to develop a xenon lamp aging device that supports multi-mode precise spraying, avoids cross-contamination, improves coverage uniformity, and achieves efficient waste liquid recovery, in order to meet the increasingly stringent requirements for material weather resistance testing. Summary of the Invention

[0005] This invention overcomes the problems of traditional equipment, such as single spray mode, residual liquid pollution, uneven coverage, and low waste liquid treatment efficiency, and significantly improves the accuracy of aging tests, the realism of environmental simulation, and resource utilization.

[0006] To achieve the above objectives, the present invention adopts the following solution: A xenon lamp aging machine for plastic parts with a spray system, comprising: The aging chamber contains an area for placing plastic parts and a xenon lamp light source that illuminates the area for placing plastic parts. The sprinkler system includes a liquid supply unit, a nozzle unit, a liquid recovery device, and a control unit; wherein, The liquid supply unit includes a water storage tank, a chemical solution storage tank, a first supply pipeline, a second supply pipeline, and a four-way switching valve with two inlets and two outlets. The water storage tank is connected to the first input end of the four-way switching valve through the first supply pipeline. A liquid mixing device is installed on the second supply pipeline. The liquid mixing device is equipped with a water inlet, a liquid inlet, and a liquid outlet. The water inlet is connected to the water storage tank through the first flow regulating valve, the liquid inlet is connected to the chemical solution storage tank through the second flow regulating valve, and the liquid outlet is connected to the second input end of the four-way switching valve. The nozzle unit includes multiple multi-directional adjustable nozzles with angle adjustment mechanisms. The multiple multi-directional adjustable nozzles are arranged in the aging chamber and point towards the plastic part placement area. The input end of the nozzle unit is connected to the first output end of the four-way switching valve. The liquid recovery device includes a collection tank, a recovery pipeline, a drain pipeline, and a recovery storage tank. The collection tank is located at the bottom of the aging chamber to receive the liquid after spraying. The inlet of the recovery pipeline is connected to the bottom of the collection tank, and the outlet of the recovery pipeline is connected to the recovery storage tank via a recovery pump. The inlet of the drain pipeline is connected to the second output end of a four-way switching valve, and the outlet of the drain pipeline is connected to the inlet of the recovery pipeline. A drain control valve is installed on the drain pipeline. The control unit controls the four-way switching valve, the first flow regulating valve, the second flow regulating valve, the angle adjustment mechanism of the multi-directional regulating nozzle, the recovery pump, and the drain control valve via communication signals. It controls the opening degree of the first and second flow regulating valves to adjust the concentration and flow rate of the chemical solution output by the liquid mixing device, controls the four-way switching valve to select the output liquid from the water storage tank or the output mixed liquid after passing through the liquid mixing device, controls the spray angle of the multi-directional regulating nozzle, controls the drain control valve to discharge the liquid remaining in the four-way switching valve and the nozzle unit, and controls the recovery pump to recover the used liquid.

[0007] Preferably, the control unit is configured to perform the following operations: Before the spraying stage begins, the target opening values ​​of the first and second flow control valves are calculated and set based on the pre-stored plastic material type, aging test standards, and preset chemical solution concentration requirements. During the spraying process, data from the chemical concentration sensor and flow sensor installed at the liquid outlet of the liquid mixing device are collected in real time. The collected data is compared with the preset target concentration range and target flow range. When the solution concentration deviates from the target concentration range or the solution flow deviates from the target flow range, the opening of the first and / or second flow control valves is adjusted. When it is necessary to switch the spraying mode, the four-way switching valve is first controlled to connect the liquid supply unit to the drain pipe, and the drain control valve is opened to drain the liquid remaining in the four-way switching valve and nozzle unit. Then, the four-way switching valve is controlled to switch to the target liquid supply source and the drain control valve is closed. Finally, the spraying of the target liquid is started.

[0008] Preferably, the target opening value is calculated as follows: The control unit calls the pre-stored flow coefficient calculation formula. Where Q is the flow rate, Cv is the valve flow coefficient, and ∆P is the pressure difference detected by the pressure sensor installed at the supply pipeline and the back pressure sensor installed at the nozzle unit; for the first flow regulating valve, the target pure water flow rate is substituted into the formula to deduce its water flow coefficient Cv. water Then, based on the valve characteristic curve data of the first flow regulating valve, Cv is... water Convert to first basic opening percentage K water For the second flow control valve, substitute the target chemical solution flow rate value into the formula to deduce its chemical solution flow coefficient Cv. chem And based on the valve characteristic curve data of the second flow control valve, Cv chem Convert to second basic opening percentage K chem The final target opening value is generated by superimposing the basic opening percentage with the historical deviation compensation coefficient, where the historical deviation compensation coefficient is the average proportional deviation between the measured value of the flow sensor and the target value in the three most recent tasks of preparing the same type of solution.

[0009] Preferably, the control unit controls the liquid recovery device in the following ways: Before the drain control valve is opened to perform the evacuation operation, the control unit first determines the type of residual liquid in the four-way switching valve and nozzle unit that are about to be emptied. If the residual liquid is a chemical solution or a mixed solution, the control unit maintains the operation of the recovery pump and ensures that the recovery pipeline is unobstructed, so that the discharged residual liquid enters the recovery pipeline through the drain pipeline and is then transported to the recovery storage tank by the recovery pump. If the residual liquid is pure water, the control unit controls a three-way switching valve installed on the recovery pipeline at the same time as opening the drain control valve, switching the outlet of the recovery pipeline to the water storage tank instead of the recovery storage tank.

[0010] Preferably, the control unit controls the spraying of the nozzle unit, including: During the spraying process, the control unit monitors the flow sensor data in the branch pipes corresponding to each multi-directional adjustable nozzle in real time. When the real-time flow value of a certain nozzle is detected to be continuously lower than the preset flow threshold and deviates from the average flow value of the same group of nozzles by more than the allowable deviation range, the control unit determines that the nozzle is partially blocked and performs the following anti-blockage response operation: First, increase the liquid supply pressure of the branch pipe where the nozzle is located and maintain a short pulse time to try to flush out the blockage. If the flow does not recover, close the liquid supply valve of the nozzle and mark it as faulty. At the same time, based on the space coverage requirements of the plastic part placement area, the control unit adjusts the angle adjustment mechanism of the nozzle adjacent to the faulty nozzle to increase its spray coverage range to compensate for the missing area of ​​the faulty nozzle.

[0011] Preferably, the control unit coordinates the xenon lamp light source and the spray system in the following manner: During the aging test cycle, the control unit divides the irradiation intensity of the xenon lamp light source into multiple continuous stages based on the pre-stored test program, and synchronously starts the spray system at the end of each stage. Before the spray starts, the control unit calculates the estimated temperature rise data of the plastic part surface based on the xenon lamp irradiation intensity value and duration of the current stage. Based on the estimated temperature rise data, the control unit dynamically adjusts the duration and liquid flow rate of the next stage of spraying. The higher the xenon lamp irradiation intensity or the longer the duration, the longer the corresponding spraying duration and the larger the flow rate. After the spraying ends, the control unit introduces an adjustable time interval before starting the next stage of xenon lamp irradiation. This time interval is calculated and determined based on the liquid evaporation rate model of the previous spraying.

[0012] Preferably, the method for constructing the liquid evaporation rate model is as follows: Under standard environmental conditions, multiple sets of control experiments were conducted. Each set of experiments included fixed xenon lamp irradiation intensity, spray flow rate, and aging room temperature and humidity parameters. Image sensors continuously collected data on the morphological changes of the liquid film on the surface of the plastic parts after spraying. Based on the morphological change data, the liquid film area reduction rate was extracted as the actual evaporation rate. Multiple linear regression analysis was performed on the actual evaporation rate against synchronously monitored data from plastic part surface temperature sensors, ambient humidity sensors, xenon lamp irradiance, and initial liquid film thickness. This generated a mathematical model with temperature (T), humidity (RH), irradiance (I), and liquid film thickness (D) as independent variables and evaporation rate (Evaporation-Rate) as the dependent variable. This mathematical model was normalized and stored as a liquid evaporation rate model, with the expression: Evaporation-Rate = k1·T + k2·RH + k3·I + k4·D + C, where k1-k4 are the weighting coefficients for temperature, humidity, irradiance, and liquid film thickness, respectively, and the constant term C is the baseline evaporation rate.

[0013] Preferably, the liquid evaporation rate model is dynamically corrected using the following method: The control unit collects humidity sensor data in the aging chamber in real time; during the delay time interval after each spray, it continuously monitors image sensor data of residual liquid film on the surface of the plastic parts placement area, and calculates the actual evaporation rate by analyzing the liquid film area reduction rate; the actual evaporation rate is compared with the theoretical evaporation rate calculated based on the current xenon lamp irradiation intensity and the preset model. When the deviation exceeds the allowable threshold, the environmental humidity weight coefficient in the evaporation rate model is adjusted according to a predetermined ratio, and the updated model is used for the calculation of the delay interval after subsequent sprays.

[0014] Preferably, the control unit controls the liquid mixing device in the following ways: Before each spraying task begins, the control unit executes a concentration calibration procedure. This procedure includes closing the second flow regulating valve and opening the first flow regulating valve to a predetermined opening degree, allowing pure water to flow into the liquid mixing device; reading the conductivity sensor data at the outlet of the liquid mixing device as a reference value; then closing the first flow regulating valve and opening the second flow regulating valve to a preset opening degree, allowing the chemical solution to flow into the liquid mixing device; reading the conductivity sensor data again as a reference value for the chemical solution; and calculating the precise opening compensation parameters for the first and second flow regulating valves based on the reference value, the chemical solution reference value, and the target mixed solution concentration requirement. During subsequent spraying, the control unit superimposes the opening compensation parameters onto the target opening values ​​of the first and second flow regulating valves to dynamically correct the chemical solution concentration.

[0015] Preferably, the method for calculating and superimposing the opening compensation parameters is as follows: the control unit calculates the parameters based on the reference value G.base Reference value G for chemical solutions ref The ratio relationship, combined with the target mixed solution concentration C target The theoretical conductivity of the mixed solution was calculated. C max The initial concentration of the chemical solution; during subsequent spraying, the conductivity sensor data G at the outlet of the liquid mixing device is collected in real time. actual The allowable deviation threshold for conductivity is set to δ. When |G is detected... actual -G target When |>δ, the dynamic compensation amount ΔK is calculated using the following formula: K p K is the instantaneous deviation amplification factor. i The cumulative deviation amplification factor is used; ΔK is allocated according to the weighting factor α as the compensation parameter ΔK for the opening of the first flow control valve. water The second flow control valve opening compensation parameter ΔK is allocated according to the weighting coefficient β. chem α and β are the compensation weights assigned to the first and second flow control valves, respectively, and α + β = 1; ΔK water The original target opening value K superimposed on the first flow control valve water Above, ΔK chem The original target opening value K superimposed on the second flow control valve chem The final target opening values ​​of the two valves are obtained.

[0016] The present invention includes at least the following beneficial effects: (1) Through the coordinated design of the four-way switching valve and the drain pipe, the non-polluting switching of the spray liquid type is realized, and the risk of cross-contamination caused by residual liquid is completely eliminated; the multi-directional adjustable nozzle layout combined with closed-loop flow control ensures the uniformity of spray coverage for plastic parts of different shapes; the liquid recovery device classifies and treats waste liquid, significantly reducing the consumption of water resources and chemical reagents; (2) Based on the pre-calculation and real-time feedback of the valve opening dynamic control (including historical deviation compensation), the stability of the mixed solution concentration is significantly improved, especially ensuring the long-term test accuracy of low concentration solutions; the active dredging process of mode switching is automated, avoiding manual intervention. Predicted error; (3) Intelligent classification and recycling of residual liquid (pure water reuse / centralized treatment of chemical liquid) improves resource utilization; Automatic diagnosis of nozzle blockage and dynamic angle compensation mechanism of adjacent nozzles ensure test continuity and data reliability, and reduce maintenance frequency; (4) Multi-parameter collaborative control of light-liquid-heat simulates the correlation of real environment; The self-correction capability of evaporation model improves the surface state control accuracy, and makes the correlation between laboratory accelerated aging and outdoor exposure significantly enhanced; (5) Conductivity dual-level calibration (reference value + real-time feedback) combined with adaptive PID compensation algorithm solves the problem of low concentration solution control; Fully automatic process replaces manual calibration, and efficiency is significantly improved. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structural principle of a xenon lamp aging machine for plastic parts with a spray system provided by the present invention. Detailed Implementation

[0018] The present invention will now be described in further detail with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0019] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not exclude the presence or addition of one or more other elements or combinations thereof.

[0020] It should be noted that, unless otherwise specified, the experimental methods described in the following embodiments are conventional methods, and the materials described are commercially available unless otherwise specified. In the description of this invention, it should be noted that, unless otherwise explicitly stated and limited, the terms "installation," "connection," and "setting" should be interpreted broadly. For example, they can refer to fixed connection or setting, detachable connection or setting, or integral connection or setting. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. The terms "lateral," "longitudinal," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0021] like Figure 1 As shown, the xenon lamp aging machine for plastic parts with a spray system provided by the present invention includes: The aging chamber contains an area for placing plastic parts and a xenon lamp light source that illuminates the area for placing plastic parts. The sprinkler system includes a liquid supply unit, a nozzle unit, a liquid recovery device, and a control unit; wherein, The liquid supply unit includes a water storage tank, a chemical solution storage tank, a first supply pipeline, a second supply pipeline, and a four-way switching valve with two inlets and two outlets. The water storage tank is connected to the first input end of the four-way switching valve through the first supply pipeline. A liquid mixing device is installed on the second supply pipeline. The liquid mixing device is equipped with a water inlet, a liquid inlet, and a liquid outlet. The water inlet is connected to the water storage tank through the first flow regulating valve, the liquid inlet is connected to the chemical solution storage tank through the second flow regulating valve, and the liquid outlet is connected to the second input end of the four-way switching valve. The nozzle unit includes multiple multi-directional adjustable nozzles with angle adjustment mechanisms. The multiple multi-directional adjustable nozzles are arranged in the aging chamber and point towards the plastic part placement area. The input end of the nozzle unit is connected to the first output end of the four-way switching valve. The liquid recovery device includes a collection tank, a recovery pipeline, a drain pipeline, and a recovery storage tank. The collection tank is located at the bottom of the aging chamber to receive the liquid after spraying. The inlet of the recovery pipeline is connected to the bottom of the collection tank, and the outlet of the recovery pipeline is connected to the recovery storage tank via a recovery pump. The inlet of the drain pipeline is connected to the second output end of a four-way switching valve, and the outlet of the drain pipeline is connected to the inlet of the recovery pipeline. A drain control valve is installed on the drain pipeline. The control unit controls the four-way switching valve, the first flow regulating valve, the second flow regulating valve, the angle adjustment mechanism of the multi-directional regulating nozzle, the recovery pump, and the drain control valve via communication signals. It controls the opening degree of the first and second flow regulating valves to adjust the concentration and flow rate of the chemical solution output by the liquid mixing device, controls the four-way switching valve to select the output liquid from the water storage tank or the output mixed liquid after passing through the liquid mixing device, controls the spray angle of the multi-directional regulating nozzle, controls the drain control valve to discharge the liquid remaining in the four-way switching valve and the nozzle unit, and controls the recovery pump to recover the used liquid.

[0022] The xenon lamp aging machine for plastic parts with a spray system provided in this solution mainly includes an aging environment simulation body, a precision spray system, and a central coordination and control unit. They work together to simulate the accelerated aging process of plastic parts in complex outdoor environments.

[0023] The core of the aging environment simulation system is a sealed aging chamber. Inside this chamber, a specially designed area is used to hold various plastic samples for testing. The most critical environmental simulation light source is a xenon lamp that illuminates the plastic sample area. This light source can simulate the full spectrum of sunlight, especially the ultraviolet radiation, which is the main factor causing photoaging of plastics. The xenon lamps are precisely positioned to ensure that their light uniformly covers all plastic samples within the area, thus providing standardized photo-irradiation aging conditions. The aging chamber itself is designed with excellent thermal insulation and sealing performance to maintain stable internal environmental parameters.

[0024] To simulate environmental conditions such as rain, acid rain, cleaning, or chemical solution exposure, a highly automated sprinkler system was integrated. This system includes subsystems for liquid supply, atomization spraying, recycling and treatment, and intelligent control. The liquid supply unit is responsible for providing purified liquids (usually water) and chemical solutions of specific concentrations. It comprises two separate storage containers: a water tank for storing deionized or purified water, and a chemical solution tank for storing pre-prepared concentrated chemical reagents (such as acidic solutions simulating acid rain, cleaning agents, or other corrosive solutions). Liquid delivery is achieved through a piping system, incorporating a crucial fluid switching component: a two-inlet, two-outlet four-way switching valve. This valve has two inlet ports and two outlet ports, and the connection between these ports can be flexibly switched under system control. The first supply line directly connects the water tank to the first inlet of the four-way switching valve. To prepare mixed solutions of different concentrations as needed, the system includes a second supply line equipped with a liquid mixing device (e.g., a static mixer or a small mixing chamber). This mixing device has a water inlet, a liquid outlet, and a liquid outlet. The water inlet is connected to the water tank via a first flow control valve, and the liquid outlet is connected to the chemical solution tank via a second flow control valve. By precisely controlling the opening of these two regulating valves, water and concentrated chemical solutions can be fed into the mixing device in proportion for uniform mixing. The mixed solution flows out from the outlet and connects to the second input of the four-way switching valve. The four-way valve can therefore select to deliver pure water (from the first input) or a mixed solution of a predetermined concentration (from the second input) downstream.

[0025] The nozzle unit is responsible for atomizing and precisely spraying the supplied liquid onto the surface of the plastic part. This unit includes multiple multi-directional adjustable nozzles with angle adjustment mechanisms. These nozzles are carefully arranged inside the aging chamber, with their nozzles pointing downwards towards the area where the plastic part is placed. The angle adjustment mechanism of each nozzle (which can be driven by a micro stepper motor or servo motor) allows for a range of angle adjustments in both the horizontal and vertical directions (e.g., ±30 degrees or more), thereby changing the spray coverage direction and impact point. The input of the nozzle unit is connected via piping to the first output of a four-way switching valve, receiving liquid from the liquid supply unit. The selection and arrangement of the nozzles ensure that the spray liquid uniformly covers plastic part samples of different shapes and positions, simulating a real liquid contact scenario.

[0026] The liquid recovery system aims to collect, separate, and reuse spray liquids, improving resource utilization efficiency and reducing waste discharge. The core of the system is a collection tank located at the bottom of the aging chamber, its funnel-shaped design effectively collecting all dripping or flowing liquid after spraying. The inlet of the recovery pipeline connects to the bottom of the collection tank, and its outlet connects to a recovery storage tank via a recovery pump. The recovery pump powers the pumping of the collected liquid to the recovery storage tank for temporary storage. Furthermore, to remove residual liquid from the supply lines and nozzles and prevent cross-contamination when switching spray modes (e.g., from spraying chemical solutions to spraying pure water), a drain pipeline is included. The inlet of the drain pipeline connects to the second output of a four-way switching valve, and its outlet connects to the inlet of the recovery pipeline (before the recovery pump, ensuring it can merge with the recovery flow). A drain control valve (e.g., a solenoid valve) is installed on the drain pipeline to control the opening and closing of the drain operation. When the valve is opened and the four-way valve is switched to the drain mode, the residual liquid will flow from the second output end through the drain line into the recovery line and eventually be pumped into the recovery storage tank.

[0027] The control unit, acting as the brain of the entire sprinkler system, centrally controls all key actuators via communication signals (such as electrical signals and digital bus signals), achieving intelligent and automated spraying. Its core control functions include: Concentration and Flow Control: By controlling the opening degrees of the first and second flow regulating valves, the flow ratio of water and chemical solution flowing into the liquid mixing device is adjusted in real time. A larger opening degree generally results in a larger flow rate (flow rate is related to the opening degree and pipeline pressure). Through precise calculation and dynamic adjustment of the opening degrees of these two valves, the control unit can ensure that the mixed solution output from the liquid mixing device reaches the preset target concentration (e.g., 5% sulfuric acid solution) and the required total flow rate.

[0028] Liquid source selection: Controls the operation of the four-way switching valve (e.g., switching the valve core position via electromagnetic drive) to determine whether to supply pure water from the water storage tank to the nozzle unit or a mixed solution from the liquid mixing device.

[0029] Spray coverage optimization: Commands are sent to the angle adjustment mechanism of each multi-directional adjustable nozzle to drive it to a preset angle position. This allows for dynamic adjustment of the spray angle and coverage of each nozzle according to the shape, location distribution of the plastic part, or specific test requirements, ensuring no blind spots in the spray or simulating liquid impact in a specific direction.

[0030] Pipeline purging to prevent contamination: Before or after switching the spray liquid type (e.g., from a chemical solution to water), open the drain control valve and simultaneously switch the four-way valve to drain mode (i.e., the first input is connected to the second output, or the second input is connected to the second output). This forces out any residual liquid from the previous type inside the four-way switching valve and in the pipes connecting the nozzle unit. The liquid is then drained into the recovery pipe and finally into the recovery storage tank, effectively preventing cross-contamination between different liquids and ensuring the purity or concentration accuracy of the next round of spray liquid.

[0031] Liquid recovery management: Start and stop the operation of the recovery pump to promptly pump the used spray liquid collected in the collection tank to the recovery storage tank for subsequent possible treatment (such as filtration, neutralization) or compliant discharge.

[0032] Compared to existing technologies, the xenon lamp aging machine for plastic parts with a spray system provided in this solution has significant technical advantages. By integrating pure water supply, online on-demand mixing of chemical solutions, multi-directional adjustable nozzles, and a residual liquid recovery system, it simulates multiple spray modes (pure water spray, specific concentration chemical solution spray) within a single device. The concentration and flow rate can be precisely adjusted, overcoming the shortcomings of traditional equipment such as single function, cumbersome solution changes, and inaccurate concentration control. The unique four-way switching valve combined with the drain pipeline and drain control valve design can actively remove residual liquid from the pipeline and nozzles when switching liquid types, preventing residual liquid evaporation and chemical condensation, and minimizing the risk of cross-contamination between different test solutions, ensuring the purity of each spray test condition and the repeatability of results. This is a key advancement compared to devices with simple switching valves or no active venting design. Multiple nozzles with independent angle adjustment mechanisms allow for dynamic adjustment of the spray direction and coverage area according to the actual placement of the plastic parts. This significantly improves the spray uniformity for samples with complex shapes or irregular arrangements, reduces blind spots in the test, and more realistically simulates liquid contact conditions in actual environments compared to fixed nozzle designs. The liquid recovery system (collection tank, recovery pump, and recovery storage tank) ensures effective collection of the sprayed liquid, facilitating subsequent processing or reuse (e.g., for pure water spraying after purification). This significantly reduces wastewater discharge and fresh water consumption during the testing process, reflecting a green and environmentally friendly design philosophy. The powerful control unit enables centralized and automated control of key aspects such as valve opening, liquid source selection, nozzle angle, evacuation operation, and recovery pump start / stop. This greatly reduces the need for manual intervention, improves testing efficiency, reduces operational complexity, and minimizes the possibility of human error, ensuring the consistency and reliability of the testing process.

[0033] In another technical solution, the control unit is configured to perform the following operations: Before the spraying stage begins, the target opening values ​​of the first and second flow control valves are calculated and set based on the pre-stored plastic material type, aging test standards, and preset chemical solution concentration requirements. During the spraying process, data from the chemical concentration sensor and flow sensor installed at the liquid outlet of the liquid mixing device are collected in real time. The collected data is compared with the preset target concentration range and target flow range. When the solution concentration deviates from the target concentration range or the solution flow deviates from the target flow range, the opening of the first and / or second flow control valves is adjusted. When it is necessary to switch the spraying mode, the four-way switching valve is first controlled to connect the liquid supply unit to the drain pipe, and the drain control valve is opened to drain the liquid remaining in the four-way switching valve and nozzle unit. Then, the four-way switching valve is controlled to switch to the target liquid supply source and the drain control valve is closed. Finally, the spraying of the target liquid is started.

[0034] Before the spraying phase begins, the control unit retrieves pre-stored databases of plastic materials (such as polycarbonate and ABS) and aging test standards (such as ISO 4892 and SAE J2527), combined with user-defined chemical solution concentration requirements (e.g., 5% sulfuric acid solution or 3% salt solution). Based on these parameters, the system automatically calculates the initial target opening values ​​for the first flow control valve (controlling pure water) and the second flow control valve (controlling the chemical solution). The calculation process comprehensively considers physical constraints such as pipeline pressure, valve flow characteristics, and mixing device volume. During the spraying process, chemical concentration sensors (such as conductivity meters or pH meters) and flow sensors (such as turbine flow meters) installed at the liquid mixing device outlet continuously collect data. The control unit compares the real-time concentration with the preset target range (e.g., concentration ±0.5%, flow rate ±5%) at millisecond-level frequency. If the solution concentration is detected to exceed the allowable deviation (e.g., the actual concentration of 4.2% is lower than the target range of 4.5%-5.5%), the system will dynamically adjust the valve opening: when the concentration is too low, the opening of the chemical solution valve will be increased while the opening of the pure water valve will be finely adjusted simultaneously; conversely, the operation will be reversed. Flow deviations will be stabilized by proportionally adjusting the opening of the two valves to maintain a stable total flow rate.

[0035] When switching from pure water spraying to chemical solution spraying (or vice versa), the control unit executes a strict evacuation protocol. First, the four-way switching valve is rotated to the "drain position" (i.e., the first input is connected to the second output, or the second input is connected to the second output), and simultaneously the drain control valve on the drain line is opened. At this time, the residual liquid (approximately 50-200 mL) in the supply line and nozzle unit is drained into the recovery system under gravity or back pressure. The evacuation time is typically 3-10 seconds (the completion status can be monitored by a pressure sensor). After confirming evacuation, the four-way valve switches to the target liquid source (e.g., chemical mixture position), the drain valve is closed, and finally, the spraying of the target liquid is initiated. This process prevents residual pure water from diluting the chemical solution or residual chemical solution from contaminating the pure water system.

[0036] Through dual regulation of pre-calculation and real-time feedback, the system significantly improves the concentration stability of mixed solutions (reducing the fluctuation range to a fraction of that of traditional manual mixing), with particularly outstanding control precision for low-concentration solutions (such as 0.1% detergent). The active evacuation design during mode switching eliminates the risk of cross-contamination caused by valve dead zones in traditional equipment, greatly improving the reliability of data from multiple alternating spray tests. The overall process automation reduces manual intervention by more than 90%, making it especially suitable for composite aging tests (such as light-spray-drying cycles) that require frequent switching of spray modes.

[0037] The method for calculating the target opening value is as follows: The control unit calls the pre-stored flow coefficient calculation formula. Where Q is the flow rate, Cv is the valve flow coefficient, and ∆P is the pressure difference detected by the pressure sensor installed at the supply pipeline and the back pressure sensor installed at the nozzle unit; for the first flow regulating valve, the target pure water flow rate is substituted into the formula to deduce its water flow coefficient Cv. water Then, based on the valve characteristic curve data of the first flow control valve, Cv water Convert to first basic opening percentage K water For the second flow control valve, substitute the target chemical solution flow rate value into the formula to deduce its chemical solution flow coefficient Cv. chem And based on the valve characteristic curve data of the second flow control valve, Cv chem Convert to second basic opening percentage K chem The final target opening value is generated by superimposing the basic opening percentage with the historical deviation compensation coefficient, where the historical deviation compensation coefficient is the average proportional deviation between the measured value of the flow sensor and the target value in the three most recent tasks of preparing the same type of solution.

[0038] When the control unit calculates the target opening degree, the flow coefficient formula is used as the basis. For the first flow regulating valve (pure water valve), the system substitutes the user-set target pure water flow rate (e.g., 8 L / min) into the formula, and simultaneously reads the real-time pressure difference ∆P (typical value 0.2-0.8 MPa) from the supply pipeline pressure sensor (installed at the water storage tank outlet) and the nozzle unit back pressure sensor (installed at the nozzle manifold). The required water flow coefficient Cv for the current operating condition is obtained through back-calculation. water (Dimensionless parameter, reflecting the valve's flow capacity). Similarly, the second flow control valve (chemical valve) calculates Cv based on the target chemical solution flow rate. chem The process implicitly compensates for differences in fluid viscosity (the viscosity difference between pure water and chemical solutions can be several times).

[0039] After obtaining the Cv value, the control unit calls the pre-stored valve characteristic curve (provided by the valve manufacturer, usually an opening % - Cv value mapping table). For example, when Cv... water When the value is 12, the corresponding first basic opening percentage K can be obtained by querying the curve. water =45%. To eliminate system errors caused by valve wear and pipe scaling during long-term use, the system introduces a historical deviation compensation coefficient: It automatically retrieves the proportional deviation between the measured value and the target value of the flow sensor in the three most recent similar tasks (such as "5% sulfuric acid solution spraying") (e.g., deviations of +3%, -1%, and +2%), calculates its average value (here +1.3%), and adds it to the base opening as compensation. The final target opening of the first valve = K water × (1 + 1.3%) = 45.6%, the same applies to the second valve.

[0040] This algorithm combines theoretical models with historical experience data, significantly improving the long-term stability of flow control. Flow rate decline due to valve aging in traditional equipment (typically 5-10% per year) is dynamically compensated for in this system, eliminating the need for frequent calibration throughout the equipment's lifespan. Historical deviation compensation is particularly suitable for handling gradual failures such as changes in chemical solution viscosity (e.g., low-temperature crystallization) or filter clogging, maintaining flow control errors within ±3% (compared to over ±10% with traditional methods). For highly corrosive solutions (e.g., hydrofluoric acid), the system automatically reduces the compensation weight of the chemical valve (avoiding excessive opening and accelerated wear), demonstrating an intelligent risk avoidance strategy.

[0041] In another technical solution, the control unit controls the liquid recovery device in the following ways: Before the drain control valve is opened to perform the evacuation operation, the control unit first determines the type of residual liquid in the four-way switching valve and nozzle unit that are about to be emptied. If the residual liquid is a chemical solution or a mixed solution, the control unit maintains the operation of the recovery pump and ensures that the recovery pipeline is unobstructed, so that the discharged residual liquid enters the recovery pipeline through the drain pipeline and is then transported to the recovery storage tank by the recovery pump. If the residual liquid is pure water, the control unit controls a three-way switching valve installed on the recovery pipeline at the same time as opening the drain control valve, switching the outlet of the recovery pipeline to the water storage tank instead of the recovery storage tank.

[0042] Before performing the purging operation, the control unit automatically determines the type of residual liquid by analyzing current and historical spray records. Specifically, if the previous spray cycle used a chemical solution storage tank for supply (such as sulfuric acid solution) or a mixed solution output from a liquid mixing device (such as salt spray solution), the residual liquid is determined to be a chemical solution or a mixed solution; if the previous cycle only used a water storage tank for supply (such as pure water spray), it is determined to be pure water. The judgment is based on the most recent switching record of the four-way switching valve, the historical opening data of the flow control valve, and the spray task log. For example, if the system record shows that the second flow control valve was opened within the past 30 minutes, even if the current pipeline mainly contains pure water, it is still conservatively judged to contain chemical residue risk.

[0043] The control unit performs classified recycling based on different types of residual liquid: Chemical / Mixed Solution Recovery: Before opening the drain control valve, ensure the recovery pump is continuously running and the recovery pipeline is unobstructed (verified by a pressure sensor). The discharged residual liquid (approximately 100-500 mL) flows into the recovery pipeline through the drain pipeline and is then directly pumped to the recovery storage tank (made of corrosion-resistant material). The entire process is completed within 5-15 seconds, during which the flow rate in the recovery pipeline is monitored to confirm the emptying efficiency.

[0044] Pure water recovery: Simultaneously with opening the drain control valve, the three-way switching valve (such as an electric ball valve) installed on the recovery pipeline switches the flow direction. Specifically, this involves closing the port leading to the recovery storage tank and opening the port leading to the water storage tank. Residual pure water, after entering the recovery pipeline through the drain pipeline, is then pumped back to the water storage tank instead of the recovery storage tank by the recovery pump. This operation can save water treatment costs, with typical water savings reaching 5%-15% of the water used in a single spray cycle.

[0045] This design enables precise classification and recycling of residual liquids. Chemical solutions are centrally processed in a dedicated recycling tank, preventing contamination of the pure water system. Pure residual water is directly recycled, significantly reducing the cost of deionized water production. Compared to traditional equipment that mixes all residual liquids for recycling (resulting in the contamination of a large amount of reusable pure water), this solution increases water resource utilization several times over and reduces the amount of chemical waste liquid treated by a considerable proportion. The intelligent switching of the three-way valve ensures seamless operation, eliminating the risk of misconnection that may occur with manual switching.

[0046] In another technical solution, the control unit's spray control of the nozzle unit includes: During the spraying process, the control unit monitors the flow sensor data in the branch pipes corresponding to each multi-directional adjustable nozzle in real time. When the real-time flow value of a certain nozzle is detected to be continuously lower than the preset flow threshold and deviates from the average flow value of the same group of nozzles by more than the allowable deviation range, the control unit determines that the nozzle is partially blocked and performs the following anti-blockage response operation: First, increase the liquid supply pressure of the branch pipe where the nozzle is located and maintain a short pulse time to try to flush out the blockage. If the flow does not recover, close the liquid supply valve of the nozzle and mark it as faulty. At the same time, based on the space coverage requirements of the plastic part placement area, the control unit adjusts the angle adjustment mechanism of the nozzle adjacent to the faulty nozzle to increase its spray coverage range to compensate for the missing area of ​​the faulty nozzle.

[0047] The control unit continuously monitors flow data using high-precision flow sensors (range 0.5-20 L / min, accuracy ±1.5%FS) installed on each nozzle branch pipe, sampling 10 times per second. When the real-time flow value of a nozzle is detected to be consistently below a preset flow threshold (e.g., a threshold set at 60% of the standard flow rate; if the standard flow rate is 5 L / min, the threshold is 3 L / min), and deviates from the average flow value of the nozzles in the same group by more than the allowable deviation range (e.g., allowable deviation ±15%; if the average flow rate is 4.8 L / min, the allowable range is 4.08-5.52 L / min), a blockage warning is triggered. The system requires this state to persist for 3-5 seconds (configurable) to eliminate transient fluctuations and ensure continuous abnormality.

[0048] The execution process after determining the blockage consists of three steps: During the pulse flushing phase: The control unit immediately increases the liquid supply pressure of the branch pipeline where the nozzle is located (by adjusting the upstream booster pump, the typical pressure value is increased from 0.3MPa to 0.6-0.8MPa), maintaining the high-pressure pulse for 0.5-2 seconds (the time adapts to the severity of the blockage). Flow recovery is monitored in real time during flushing.

[0049] Fault isolation phase: If the flow rate does not recover to above the threshold (e.g., still below 3.2L / min), close the dedicated liquid supply solenoid valve of the branch pipeline (response time <100ms), stop the liquid supply to the nozzle and mark it as a fault state to avoid ineffective liquid supply affecting the overall pressure balance.

[0050] Coverage compensation phase: Based on a pre-stored 3D coordinate map of the plastic part placement area (via laser scanning or manual preset), the spatial coordinates of the original coverage area of ​​the faulty nozzle are calculated. The control unit automatically selects adjacent nozzles (usually 2-4) with high overlap with this area and sends adjustment commands to their angle adjustment mechanisms (e.g., horizontal rotation of 10-25 degrees, pitch increase of 5-15 degrees). After adjustment, the coverage area of ​​the adjacent nozzles expands to the original faulty area, and the overall coverage uniformity deviation is controlled within 8%.

[0051] This mechanism transforms traditional manual inspection-based blockage handling (which typically leads to downtime of several hours) into a second-level automatic response: pulse flushing resolves approximately 70% of initial soft blockages (such as bubble aggregation and particle deposition); rapid isolation prevents single-point failures from spreading to the entire spray system; and dynamic angle compensation ensures uninterrupted testing, which is particularly significant for continuous aging tests lasting thousands of hours. Compared to fixed-nozzle equipment, which carries the risk of test failure due to localized blockages (such as a plastic part not being sprayed), this solution significantly improves system availability while reducing maintenance frequency by several times.

[0052] In another technical solution, the control unit coordinates the xenon lamp light source and the spray system in the following manner: During the aging test cycle, the control unit divides the irradiation intensity of the xenon lamp light source into multiple continuous stages based on the pre-stored test program, and synchronously starts the spray system at the end of each stage. Before the spray starts, the control unit calculates the estimated temperature rise data of the plastic part surface based on the xenon lamp irradiation intensity value and duration of the current stage. Based on the estimated temperature rise data, the control unit dynamically adjusts the duration and liquid flow rate of the next stage of spraying. The higher the xenon lamp irradiation intensity or the longer the duration, the longer the corresponding spraying duration and the larger the flow rate. After the spraying ends, the control unit introduces an adjustable time interval before starting the next stage of xenon lamp irradiation. This time interval is calculated and determined based on the liquid evaporation rate model of the previous spraying.

[0053] The control unit divides the aging test cycle into multiple consecutive illumination stages (e.g., 60-120 minutes per stage), synchronously triggering the spray system at the end of each stage. The stage division is based on a pre-stored test program (e.g., SAE J2412 for automotive interior parts testing), which defines xenon lamp irradiation intensity curves at different time points (e.g., an intensity gradient increase from 0-500 hours). Before spraying begins, the system calculates the estimated temperature rise (e.g., from 25°C to 52°C) of the plastic part surface using a thermodynamic model, based on the actual xenon lamp irradiation intensity (calibrated in real-time by a radiation sensor) and duration of the current stage, combined with the specific heat capacity parameters of the plastic material (e.g., approximately 1.8 kJ / kg·K for ABS). This model considers the heat conduction hysteresis effect and provides in-depth temperature compensation for thicker plastic parts.

[0054] Based on the estimated temperature rise, the control unit dynamically sets the duration and liquid flow rate of the next stage of spraying. When the xenon lamp intensity of the previous stage exceeds a threshold (e.g., 0.55 W / m²), the control unit will activate the next stage spraying. 2 If the spraying time exceeds the limit (e.g., >90 minutes) or the spray duration exceeds the limit (e.g., >340nm), the system automatically extends the spraying time (e.g., from the standard 30 seconds to 45-70 seconds) and increases the flow rate (e.g., from 5L / min to 7-9L / min). After spraying, the system introduces an adjustable time interval (usually 30 seconds to 5 minutes) before starting the next stage of xenon lamp irradiation. This interval is calculated based on a liquid evaporation rate model: a short interval (30-60 seconds) is used in high-temperature (>45℃) drying environments, and a long interval (3-5 minutes) is used in low-temperature and high-humidity environments to ensure that the surface of the plastic part returns to the target initial state.

[0055] This collaborative control enables the equipment to break through the traditional fixed-sequence mechanical cycle. The dynamic spray parameters simulate the correlation between scorching sun and heavy rain in the real environment (such as increased rainfall after prolonged exposure to sunlight); the adjustable interval enables precise reset of the material's wet and dry state, eliminating light scattering errors caused by residual liquid film; the temperature rise prediction model avoids overheating deformation of plastic parts (such as thin-walled parts), significantly improving the safety of testing.

[0056] The method for constructing the liquid evaporation rate model is as follows: Under standard environmental conditions, multiple sets of control experiments were conducted. Each set of experiments included fixed xenon lamp irradiation intensity, spray flow rate, and aging room temperature and humidity parameters. Image sensors continuously collected data on the morphological changes of the liquid film on the surface of the plastic parts after spraying. Based on the morphological change data, the liquid film area reduction rate was extracted as the actual evaporation rate. Multiple linear regression analysis was performed on the actual evaporation rate against synchronously monitored data from plastic part surface temperature sensors, ambient humidity sensors, xenon lamp irradiance, and initial liquid film thickness. This generated a mathematical model with temperature (T), humidity (RH), irradiance (I), and liquid film thickness (D) as independent variables and evaporation rate (Evaporation-Rate) as the dependent variable. This mathematical model was normalized and stored as a liquid evaporation rate model, with the expression: Evaporation-Rate = k1·T + k2·RH + k3·I + k4·D + C, where k1-k4 are the weighting coefficients for temperature, humidity, irradiance, and liquid film thickness, respectively, and the constant term C is the baseline evaporation rate.

[0057] A control experiment was conducted in a sealed aging chamber, with four parameters fixed for each group: xenon lamp irradiation intensity (0.3-0.8 W / m²). 2The parameters included: spray flow rate (3-10 L / min), ambient temperature and humidity (40-80℃, 20-80%RH), and initial liquid film thickness (0.1-0.5 mm, controlled by nozzle flow rate and spray time). The liquid film morphology on the plastic part surface was captured using a high-speed image sensor (200 fps sampling rate), and the liquid film area reduction rate was extracted as the actual evaporation rate (unit: mm). 2 / s). Simultaneously record data from surface temperature sensor (infrared non-contact type), ambient humidity sensor, and irradiance meter.

[0058] Thousands of sets of experimental data were imported into the analysis system, and multiple linear regression was performed. The independent variables were temperature (T), humidity (RH), irradiance (I), and liquid film thickness (D); the dependent variable was evaporation rate. The regression generated a mathematical model of the form Evaporation-Rate = k1·T + k2·RH + k3·I + k4·D + C. After normalization, the typical coefficient ranges were: k1 (temperature weight) 0.15-0.25, k2 (humidity weight) -0.08 to -0.15 (negative correlation), k3 (irradiance weight) 0.05-0.12, k4 (thickness weight) -0.03 to -0.08, and the constant term C was the baseline evaporation rate. The model validation error was controlled within ±8%.

[0059] This model is the first to quantify the effect of radiative heat on evaporation in an aging machine (traditional equipment only considers temperature and humidity); it predicts the drying kinetics under different liquid film thicknesses; and it provides a scientific basis for the interval after spraying, significantly improving the consistency of material surface condition.

[0060] The liquid evaporation rate model is dynamically corrected using the following method: The control unit collects humidity sensor data in the aging chamber in real time; during the delay time interval after each spray, it continuously monitors image sensor data of residual liquid film on the surface of the plastic parts placement area, and calculates the actual evaporation rate by analyzing the liquid film area reduction rate; the actual evaporation rate is compared with the theoretical evaporation rate calculated based on the current xenon lamp irradiation intensity and the preset model. When the deviation exceeds the allowable threshold, the environmental humidity weight coefficient in the evaporation rate model is adjusted according to a predetermined ratio, and the updated model is used for the calculation of the delay interval after subsequent sprays.

[0061] During the delay interval after each spray cycle, the control unit continuously monitors the actual evaporation rate of the residual liquid film using an image sensor (e.g., calculating the liquid film boundary shrinkage rate using an edge detection algorithm). Simultaneously, based on the current xenon lamp irradiation intensity (e.g., 0.65 W / m²), the control unit... 2 ) and evaporation rate model, calculate the theoretical evaporation rate (e.g., 1.2 mm) 2 / s). When the deviation between the actual value and the theoretical value exceeds the allowable threshold (e.g., ±15% or absolute difference > 0.2mm). 2 When / s), the model correction process is triggered.

[0062] The adjustment focuses on the weighting coefficient k2 for ambient humidity. If the actual evaporation rate consistently exceeds the theoretical value (e.g., +18%), it indicates that the current ambient humidity is lower than the model's expectation. The system then reduces the absolute value of k2 by a predetermined proportion (e.g., a correction step of 0.02 each time) to weaken its negative value, for example, adjusting it from -0.12 to -0.10, thereby enhancing the inhibitory effect of humidity on evaporation. Conversely, the system increases the absolute value of k2 (e.g., from -0.12 to -0.14). The corrected model is immediately applied to the next cycle's interval calculations, while a correction log is recorded for long-term model optimization.

[0063] This mechanism enables the equipment to continuously evolve, automatically adapting to different regional climate differences (such as high-altitude dry areas); compensating for model distortion caused by long-term sensor drift; and significantly reducing the evaporation consistency error in thousand-hour aging tests, especially improving the testing accuracy of hydrophilic plastics (such as nylon).

[0064] In another technical solution, the control unit controls the liquid mixing device in the following ways: Before each spraying task begins, the control unit executes a concentration calibration procedure. This procedure includes closing the second flow regulating valve and opening the first flow regulating valve to a predetermined opening degree, allowing pure water to flow into the liquid mixing device; reading the conductivity sensor data at the outlet of the liquid mixing device as a reference value; then closing the first flow regulating valve and opening the second flow regulating valve to a preset opening degree, allowing the chemical solution to flow into the liquid mixing device; reading the conductivity sensor data again as a reference value for the chemical solution; and calculating the precise opening compensation parameters for the first and second flow regulating valves based on the reference value, the chemical solution reference value, and the target mixed solution concentration requirement. During subsequent spraying, the control unit superimposes the opening compensation parameters onto the target opening values ​​of the first and second flow regulating valves to dynamically correct the chemical solution concentration.

[0065] Before each spraying operation begins, the control unit automatically executes a concentration calibration procedure to eliminate system errors. First, the second flow regulating valve (chemical solution valve) is closed, and the first flow regulating valve (pure water valve) is opened to a predetermined degree (e.g., 30%), allowing pure water to flow from the water storage tank through the liquid mixing device. At this time, the conductivity sensor data (unit: μS / cm) at the outlet of the mixing device is read as the reference value G. base(Typical value 1-5 μS / cm, reflecting the purity of pure water). Then close the pure water valve and open the chemical solution valve to the preset opening degree (e.g., 20%), allowing the concentrated chemical solution (e.g., a 20% NaCl solution) to flow into the mixing device. Read the conductivity data as the reference value G for the chemical solution. ref (Typical values ​​50,000-100,000 μS / cm). This step-by-step operation ensures that the two liquids do not mix or interfere with each other.

[0066] Based on the baseline value, reference value, and user-defined target mixed solution concentration Ct arget (e.g., 5% NaCl), the system calculates the theoretical conductivity value of the mixed solution (e.g., Gt). arget =12500μS / cm). This calculation implicitly assumes a linear relationship between conductivity and concentration (applicable to most salt solutions). Subsequently, an opening compensation parameter is generated. If the target concentration is low (e.g., 0.1% detergent), the compensation parameter focuses on fine-tuning the chemical valve opening (to avoid over-addition); if the target concentration is high (e.g., 10% acid), the compensation parameter prioritizes optimizing the pure water valve opening. During subsequent spraying, real-time conductivity data G... actual With G target The deviation (allowable threshold ±5%) triggers dynamic compensation. For example, when G... actual When the value remains below the target value by more than 2%, the system slightly increases the chemical valve opening by 0.1%-0.3% at a millisecond frequency.

[0067] This design upgrades traditional static calibration to a dual-insurance system of "pre-calibration + real-time feedback". The reference value measurement eliminates zero-point errors caused by electrode aging and temperature drift; dynamic compensation offsets instantaneous concentration shifts caused by pipeline residues and pressure fluctuations; and the control accuracy for low-concentration solutions (<1%) is significantly improved, avoiding test failures caused by error accumulation in traditional equipment.

[0068] The calculation and superposition method of the opening compensation parameters is as follows: the control unit calculates the parameters based on the reference value G. base Reference value G for chemical solutions ref The ratio relationship, combined with the target mixed solution concentration C target The theoretical conductivity of the mixed solution was calculated. C max The initial concentration of the chemical solution; during subsequent spraying, the conductivity sensor data G at the outlet of the liquid mixing device is collected in real time. actual The allowable deviation threshold for conductivity is set to δ. When |G is detected... actual -G target When |>δ, the dynamic compensation amount ΔK is calculated using the following formula: K p K is the instantaneous deviation amplification factor. iThe cumulative deviation amplification factor is used; ΔK is allocated according to the weighting factor α as the compensation parameter ΔK for the opening of the first flow control valve. water The second flow control valve opening compensation parameter ΔK is allocated according to the weighting coefficient β. chem α and β are the compensation weights assigned to the first and second flow control valves, respectively, and α + β = 1; ΔK water The original target opening value K superimposed on the first flow control valve water Above, ΔK chem The original target opening value K superimposed on the second flow control valve chem The final target opening values ​​of the two valves are obtained.

[0069] Theoretical conductivity G target The calculation integrates three core parameters: Reference value G base Characterizes the electrical conductivity of pure water (ideal value approaches 0, actual value contains trace amounts of ions). Reference value G ref : Reflects the upper limit of conductivity of a chemical solution at its original concentration; Target concentration ratio: C target / C max (e.g., 5% / 20%=0.25).

[0070] This calculation is based on the additivity and linearity of solution conductivity: Mixed solution conductivity = Pure water conductivity + (Chemical solution conductivity - Pure water conductivity) × Concentration ratio. For example, G ref =80000 μS / cm, G base At 2 μS / cm, a 5% target concentration corresponds to G target =2+(80000-2)×0.25≈20000μS / cm.

[0071] When the real-time conductivity G actual Deviation from G target When the threshold δ is exceeded (typically set to ±500-2000 μS / cm), the system initiates dynamic compensation, including: Instantaneous deviation response: proportional to the coefficient K p (e.g., 0.05) Amplify the current deviation (G) actual -G target ), immediately generate the opening adjustment amount; Cumulative deviation correction: Integrate the historical deviation (integration time constant 5-30 seconds), and apply the correction according to the coefficient K. i (e.g., 0.001) Generate a progressive compensation amount; Weighting strategy: The total compensation ΔK is allocated according to the weights α (pure water valve) and β (chemical valve) (typically α:β=7:3, because the pure water flow rate has a greater impact on the concentration). The final pure water valve opening = original target opening + α·ΔK, and the chemical valve opening = original target opening + β·ΔK.

[0072] This algorithm optimizes response speed, with the proportional term (K) p To handle sudden disturbances (such as bubble blockage), the set concentration is restored within 2 seconds; providing long-term stability assurance, the integral term (K) i It eliminates slow system drift (such as filter clogging), compressing the concentration fluctuation range of thousands of hours of testing to a fraction of that of traditional methods; it performs intelligent risk avoidance, automatically reducing the chemical valve compensation weight (β<0.2) for corrosive solutions to prevent excessive valve operation and accelerated damage.

[0073] The number of devices and processing scale described herein are for the purpose of simplifying the description of the invention. Applications, modifications, and variations of the invention will be readily apparent to those skilled in the art.

[0074] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A xenon lamp aging machine for plastic parts with a spray system, characterized in that, include: The aging chamber contains an area for placing plastic parts and a xenon lamp light source that illuminates the area for placing plastic parts. The sprinkler system includes a liquid supply unit, a nozzle unit, a liquid recovery device, and a control unit; wherein, The liquid supply unit includes a water storage tank, a chemical solution storage tank, a first supply pipeline, a second supply pipeline, and a four-way switching valve with two inlets and two outlets. The water storage tank is connected to the first input end of the four-way switching valve through the first supply pipeline. A liquid mixing device is installed on the second supply pipeline. The liquid mixing device is equipped with a water inlet, a liquid inlet, and a liquid outlet. The water inlet is connected to the water storage tank through the first flow regulating valve, the liquid inlet is connected to the chemical solution storage tank through the second flow regulating valve, and the liquid outlet is connected to the second input end of the four-way switching valve. The nozzle unit includes multiple multi-directional adjustable nozzles with angle adjustment mechanisms. The multiple multi-directional adjustable nozzles are arranged in the aging chamber and point towards the plastic part placement area. The input end of the nozzle unit is connected to the first output end of the four-way switching valve. The liquid recovery device includes a collection tank, a recovery pipeline, a drain pipeline, and a recovery storage tank. The collection tank is located at the bottom of the aging chamber to receive the liquid after spraying. The inlet of the recovery pipeline is connected to the bottom of the collection tank, and the outlet of the recovery pipeline is connected to the recovery storage tank via a recovery pump. The inlet of the drain pipeline is connected to the second output end of a four-way switching valve, and the outlet of the drain pipeline is connected to the inlet of the recovery pipeline. A drain control valve is installed on the drain pipeline. The control unit controls the four-way switching valve, the first flow regulating valve, the second flow regulating valve, the angle adjustment mechanism of the multi-directional regulating nozzle, the recovery pump, and the drain control valve via communication signals. It controls the opening degree of the first and second flow regulating valves to adjust the concentration and flow rate of the chemical solution output by the liquid mixing device, controls the four-way switching valve to select the output liquid from the water storage tank or the output mixed liquid after passing through the liquid mixing device, controls the spray angle of the multi-directional regulating nozzle, controls the drain control valve to discharge the liquid remaining in the four-way switching valve and the nozzle unit, and controls the recovery pump to recover the used liquid.

2. The xenon lamp aging machine for plastic parts with a spray system according to claim 1, characterized in that, The control unit is configured to perform the following operations: Before the spraying stage is started, the target opening values ​​of the first flow control valve and the second flow control valve are calculated and set based on the pre-stored plastic part material type, aging test standard and preset chemical solution concentration requirements. During the spraying process, data from the chemical concentration sensor and flow sensor installed at the outlet of the liquid mixing device are collected in real time. The collected data is compared with the preset target concentration range and target flow range. When the solution concentration deviates from the target concentration range or the solution flow deviates from the target flow range, the opening of the first flow regulating valve and / or the second flow regulating valve is adjusted. When it is necessary to switch the spraying mode, the four-way switching valve is first controlled to connect the liquid supply unit to the drain pipe, and the drain control valve is opened to drain the liquid remaining in the four-way switching valve and the nozzle unit. Then, the four-way switching valve is controlled to switch to the target liquid supply source and the drain control valve is closed. Finally, the spraying of the target liquid is started.

3. The xenon lamp aging machine for plastic parts with a spray system according to claim 2, characterized in that, The method for calculating the target opening value is as follows: The control unit calls the pre-stored flow coefficient calculation formula. Where Q is the flow rate, Cv is the valve flow coefficient, and ∆P is the pressure difference detected by the pressure sensor installed at the supply pipeline and the back pressure sensor installed at the nozzle unit; for the first flow regulating valve, the target pure water flow rate is substituted into the formula to deduce its water flow coefficient Cv. water Then, based on the valve characteristic curve data of the first flow control valve, Cv water Convert to first basic opening percentage K water For the second flow control valve, substitute the target chemical solution flow rate value into the formula to deduce its chemical solution flow coefficient Cv. chem And based on the valve characteristic curve data of the second flow control valve, Cv chem Convert to second basic opening percentage K chem The final target opening value is generated by superimposing the basic opening percentage with the historical deviation compensation coefficient, where the historical deviation compensation coefficient is the average proportional deviation between the measured value of the flow sensor and the target value in the three most recent tasks of preparing the same type of solution.

4. The xenon lamp aging machine for plastic parts with a spray system according to claim 1, characterized in that, The control unit controls the liquid recovery device in the following ways: Before the drain control valve is opened to perform the evacuation operation, the control unit first determines the type of residual liquid in the four-way switching valve and nozzle unit that are about to be emptied. If the residual liquid is a chemical solution or a mixed solution, the control unit maintains the operation of the recovery pump and ensures that the recovery pipeline is unobstructed, so that the discharged residual liquid enters the recovery pipeline through the drain pipeline and is then transported to the recovery storage tank by the recovery pump. If the residual liquid is pure water, the control unit controls a three-way switching valve installed on the recovery pipeline at the same time as opening the drain control valve, switching the outlet of the recovery pipeline to the water storage tank instead of the recovery storage tank.

5. The xenon lamp aging machine for plastic parts with a spray system according to claim 1, characterized in that, The control unit's spray control of the nozzle unit includes: During the spraying process, the control unit monitors the flow sensor data in the branch pipes corresponding to each multi-directional adjustable nozzle in real time. When the real-time flow value of a certain nozzle is detected to be continuously lower than the preset flow threshold and deviates from the average flow value of the same group of nozzles by more than the allowable deviation range, the control unit determines that the nozzle is partially blocked and performs the following anti-blockage response operation: First, increase the liquid supply pressure of the branch pipe where the nozzle is located and maintain a short pulse time to try to flush out the blockage. If the flow does not recover, close the liquid supply valve of the nozzle and mark it as faulty. At the same time, based on the space coverage requirements of the plastic part placement area, the control unit adjusts the angle adjustment mechanism of the nozzle adjacent to the faulty nozzle to increase its spray coverage range to compensate for the missing area of ​​the faulty nozzle.

6. The xenon lamp aging machine for plastic parts with a spray system according to claim 1, characterized in that, The control unit coordinates the control of the xenon lamp light source and the spray system in the following manner: During the aging test cycle, the control unit divides the irradiation intensity of the xenon lamp light source into multiple continuous stages based on the pre-stored test program, and synchronously starts the spray system at the end of each stage. Before the spray starts, the control unit calculates the estimated temperature rise data of the plastic part surface based on the xenon lamp irradiation intensity value and duration of the current stage. Based on the estimated temperature rise data, the control unit dynamically adjusts the duration and liquid flow rate of the next stage of spraying. The higher the xenon lamp irradiation intensity or the longer the duration, the longer the corresponding spraying duration and the larger the flow rate. After the spraying ends, the control unit introduces an adjustable time interval before starting the next stage of xenon lamp irradiation. This time interval is calculated and determined based on the liquid evaporation rate model of the previous spraying.

7. The xenon lamp aging machine for plastic parts with a spray system according to claim 6, characterized in that, The method for constructing the liquid evaporation rate model is as follows: Under standard environmental conditions, multiple sets of control experiments were conducted. The parameters set for each set of experiments included fixed xenon lamp irradiation intensity, spray flow rate, and aging room temperature and humidity parameters. The morphological change data of the liquid film on the surface of the plastic parts after spraying were continuously collected by an image sensor. The liquid film area reduction rate was extracted as the actual evaporation rate based on the morphological change data. Multiple linear regression analysis was performed on the actual evaporation rate and the data from the synchronously monitored plastic part surface temperature sensor, ambient humidity sensor, xenon lamp irradiance, and initial liquid film thickness to generate a mathematical model with temperature T, humidity RH, irradiance I, and liquid film thickness D as independent variables and evaporation rate (Evaporation-Rate) as the dependent variable. After normalization, this mathematical model was stored as a liquid evaporation rate model, with the expression: Evaporation-Rate = k1·T + k2·RH + k3·I + k4·D + C, where k1-k4 are the weighting coefficients of temperature, humidity, irradiance, and liquid film thickness, respectively, and the constant term C is the baseline evaporation rate.

8. The xenon lamp aging machine for plastic parts with a spray system according to claim 7, characterized in that, The liquid evaporation rate model is dynamically corrected using the following method: The control unit collects humidity sensor data in the aging chamber in real time; during the delay time interval after each spray, it continuously monitors image sensor data of residual liquid film on the surface of the plastic parts placement area, and calculates the actual evaporation rate by analyzing the liquid film area reduction rate; the actual evaporation rate is compared with the theoretical evaporation rate calculated based on the current xenon lamp irradiation intensity and the preset model. When the deviation exceeds the allowable threshold, the environmental humidity weight coefficient in the evaporation rate model is adjusted according to a predetermined ratio, and the updated model is used for the calculation of the delay interval after subsequent sprays.

9. The xenon lamp aging machine for plastic parts with a spray system according to claim 1, characterized in that, The control unit controls the liquid mixing device in the following ways: Before each spraying task begins, the control unit executes a concentration calibration procedure. This procedure includes closing the second flow regulating valve and opening the first flow regulating valve to a predetermined opening degree, allowing pure water to flow into the liquid mixing device; reading the conductivity sensor data at the outlet of the liquid mixing device as a reference value; then closing the first flow regulating valve and opening the second flow regulating valve to a preset opening degree, allowing the chemical solution to flow into the liquid mixing device; reading the conductivity sensor data again as a reference value for the chemical solution; and calculating the precise opening compensation parameters for the first and second flow regulating valves based on the reference value, the chemical solution reference value, and the target mixed solution concentration requirement. During subsequent spraying, the control unit superimposes the opening compensation parameters onto the target opening values ​​of the first and second flow regulating valves to dynamically correct the chemical solution concentration.

10. The xenon lamp aging machine for plastic parts with a spray system according to claim 9, characterized in that, The calculation and superposition method of the opening compensation parameters is as follows: the control unit calculates the parameters based on the reference value G. base Reference value G for chemical solutions ref The ratio relationship, combined with the target mixed solution concentration C target The theoretical conductivity of the mixed solution was calculated. C max The initial concentration of the chemical solution; during subsequent spraying, the conductivity sensor data G at the outlet of the liquid mixing device is collected in real time. actual The allowable deviation threshold for conductivity is set to δ. When |G is detected... actual -G target When |>δ, the dynamic compensation amount ΔK is calculated using the following formula: K p K is the instantaneous deviation amplification factor. i The cumulative deviation amplification factor is used; ΔK is allocated according to the weighting factor α as the compensation parameter ΔK for the opening of the first flow control valve. water The second flow control valve opening compensation parameter ΔK is allocated according to the weighting coefficient β. chem α and β are the compensation weights assigned to the first and second flow control valves, respectively, and α + β = 1; ΔK water The original target opening value K superimposed on the first flow control valve water Above, ΔK chem The original target opening value K superimposed on the second flow control valve chem The final target opening values ​​of the two valves are obtained.

Images