Formaldehyde environmental chamber device with background concentration self-checking and automatic cleaning function

Abstract

The utility model discloses a kind of formaldehyde environmental chamber equipment with background concentration self-checking and automatic cleaning function, the formaldehyde environmental chamber equipment includes cabin, the sample holder for placing sample is installed in the cabin, the temperature and humidity sensor for real-time monitoring environmental parameter in cabin and the air circulation device for maintaining air flow uniformity in cabin are used, the formaldehyde environmental chamber equipment also includes sampling detection module, spray cleaning module and main control system. The formaldehyde environmental chamber equipment can effectively replace the conventional means of existing dependence on artificial judgment and operation, realize the rapid judgment and cleaning response of test chamber state, greatly shorten test preparation time, reduce artificial operation frequency and detection time cost.

Description

Technical Field

[0001] This utility model relates to the technical field of indoor air quality testing, and in particular to a formaldehyde environmental chamber device with background concentration self-testing and automatic cleaning functions. Background Technology

[0002] With increasing public concern about indoor air quality and a healthy environment, the release performance of organic pollutants such as formaldehyde, benzene compounds, and TVOC (total volatile organic compounds) in building materials and decoration materials has become an important basis for evaluating the environmental friendliness of products. The closed-environment chamber method, due to its ability to simulate real indoor conditions, high test repeatability, and accurate quantitative results of pollutants, has been widely used in pollutant release testing in fields including building materials, engineered wood products, furniture, adhesives, wallpaper, and carpets.

[0003] Currently, various national and industry standards (such as GB 50325—2020 "Standard for Indoor Environmental Pollution Control of Civil Building Engineering" and GB / T 29899—2024 "Test Method for Emission of Volatile Organic Compounds from Wood-based Panels and Their Products - Small Release Chamber Method") have set high requirements for pollutant release tests, and the 1 cubic meter sealed formaldehyde environmental chamber has become one of the core test devices in these testing systems. This type of equipment typically consists of a stainless steel sealed chamber, an air sampling system, a temperature and humidity control system, and a sample holder. Although it possesses basic testing capabilities, it still faces many technical bottlenecks in practical applications.

[0004] Among existing publicly available documents, patent publication number CN106093312A discloses a detection chamber for odor, VOC, and floating hazardous substances with light-based testing capabilities. This technology utilizes an infrared heating device or sunlight-irradiation lamp externally mounted on the glass structure. It enables gas sampling within the chamber under ventilated / sealed conditions, detecting the release of volatile hazardous gases such as formaldehyde and VOCs from the tested object. Furthermore, it avoids interference from environmental factors or other uncertainties, exhibiting good stability and high testing accuracy. However, this patent has the following drawbacks;

[0005] The process of confirming the background state of the environmental chamber relies on manual judgment and traditional sampling methods, which cannot achieve online monitoring and real-time feedback, resulting in problems such as slow response and delayed judgment. If the background concentration is found to be excessive before the test, the chamber door needs to be manually opened for wiping or spraying, which has unstable cleaning effect and high labor intensity. In high-frequency test scenarios, pollutants in the chamber are prone to accumulate and cause cross-interference, resulting in distorted test data. Utility Model Content

[0006] The technical problem this invention aims to solve is to overcome the shortcomings of existing technologies by providing a formaldehyde environmental chamber device with self-detection of background concentration and automatic cleaning functions. This device combines the functions of self-detection of pollutant background concentration and automatic chamber cleaning, effectively replacing traditional methods that rely on manual judgment and operation. It enables rapid assessment of the test chamber's condition and cleaning response, significantly shortening test preparation time, reducing the frequency of manual operation and testing time costs. By deeply integrating pollutant background concentration assessment, cleaning and drying processes, and the control system, it effectively reduces human error, improves the consistency of sample testing and batch processing capabilities, and is particularly suitable for simultaneously improving testing efficiency and laboratory operating rhythm in high-throughput, multi-batch testing scenarios.

[0007] The technical solution adopted by this utility model to solve its technical problem is: a formaldehyde environmental chamber device with background concentration self-detection and automatic cleaning functions. The formaldehyde environmental chamber device includes a chamber body, in which a sample rack for placing sample positions, a temperature and humidity sensor for real-time monitoring of environmental parameters inside the chamber, and an air circulation device for maintaining uniform airflow inside the chamber are installed. The formaldehyde environmental chamber device also includes a sampling and detection module, a spray cleaning module, and a main control system. The sampling and detection module includes a sampling port, a micro air pump, and a gas sensor. The sampling port is located on the side wall of the chamber body and is connected to the inner and outer walls of the chamber body. The micro air pump is connected to the sampling port through a conduit. The gas sensor is used to detect formaldehyde and TVOC concentrations. The gas sensor includes a formaldehyde electrochemical sensor and a TVOC photoionization sensor. The sampling and detection module also includes a silicone hose, one end of which is connected to the sampling port, and the other end of which is located in the chamber body. The internal central area; the spray cleaning module includes a spray cleaning module, a liquid collection tank, an electromagnetic drain valve, and a hot air drying module. The spray cleaning module is located at the top of the inner wall of the chamber, the liquid collection tank is located at the bottom of the inner wall of the chamber, the electromagnetic drain valve is connected to the liquid collection tank, and the hot air drying module is located on the side wall of the chamber; the spray cleaning module is connected to an external storage tank and a diaphragm pump through pipelines; the hot air drying module includes a PTC heating element and a fan; the main control system is electrically connected to the micro air pump, the gas sensor, the diaphragm pump, the electromagnetic drain valve, the PTC heating element, and the fan; the spray cleaning module includes at least four evenly distributed atomizing nozzles, the spray direction covering the inner wall of the chamber, the sample rack, and the liquid collection tank; the formaldehyde environmental chamber equipment also includes an atomizing cleaning auxiliary module, which consists of an independent air pump and atomizing nozzles. The atomizing nozzles are arranged at the top of the inner wall of the chamber to cooperate with the spray cleaning module in atomizing the cleaning liquid.

[0008] To be further specific, in the above technical solution, the air outlet of the hot air drying module is provided with an air guide channel, so that the hot air forms a circulating airflow along the side wall of the cabin.

[0009] To be further specific, in the above technical solution, a liquid level sensor is provided at the bottom of the liquid collection tank, and the opening duration of the electromagnetic drain valve is dynamically adjusted by the feedback signal of the liquid level sensor.

[0010] To be further specific, in the above technical solution, the cabin adopts a double-layer heat insulation structure, with the outer shell being galvanized steel plate and the inner lining being polished stainless steel.

[0011] The beneficial effects of this utility model are as follows: The formaldehyde environmental chamber device of this utility model, which has the functions of background concentration self-detection and automatic cleaning, specifically includes the following advantages:

[0012] I. In view of the technical problems of long detection cycle and high labor cost of background concentration of pollutants in the existing technology, this utility model realizes real-time detection and rapid judgment of pollutants in the chamber by setting up a background concentration self-testing module, without the need for external testing and waiting for results, which greatly improves the pretreatment efficiency.

[0013] II. In view of the technical problems of low efficiency caused by the need for manual disassembly and cleaning of the cabin in the existing technology, this utility model achieves rapid cleaning of the cabin interior by combining automatic spraying, automatic drainage and hot air drying, ensuring cleanliness, while saving manpower.

[0014] Third, in response to the technical problem that pollutant residue accumulation affects the accuracy under high-frequency testing conditions in the existing technology, this utility model introduces an automatic cleaning and re-inspection process to ensure that the test data is in a qualified initial state before each test, thereby improving the consistency and reliability of the test data. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the structure of this utility model.

[0017] The labels in the diagram are as follows: 1. Chamber; 2. Sample rack; 3. Sample position; 4. Gas sensor; 5. Temperature and humidity sensor; 6. Temperature and humidity display and recording device; 7. Chamber air circulation device; 8. Spray cleaning module; 9. Atomized cleaning auxiliary module; 10. Liquid collection tank; 11. Hot air drying module; 12. Main control system; 13. Electromagnetic drain valve. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0019] See Figure 1 This utility model discloses a formaldehyde environmental chamber device with background concentration self-testing and automatic cleaning functions, which aims to solve the technical problems of human error, chamber pollution residue and low operation efficiency in the test preparation stage of formaldehyde release detection.

[0020] The formaldehyde environmental chamber equipment includes a chamber body 1, a sample rack 2 for placing sample positions 3, a temperature and humidity sensor 5 for real-time monitoring of environmental parameters inside the chamber body 1, and an internal air circulation device 7 for maintaining uniform air flow inside the chamber body 1. A temperature and humidity display and recording device 6 for real-time display and data recording is installed outside the chamber body 1.

[0021] Among them, the chamber 1 is the core structure of the formaldehyde environment chamber equipment. It has a cubic or cylindrical structure and adopts a double-layer heat insulation structure design. The outer shell is made of galvanized steel plate and the inner lining is made of polished stainless steel. The chamber 1 is a sealed environment chamber and is located in the central area of ​​the main body of the formaldehyde environment chamber equipment.

[0022] Specifically, there are two sample racks 2. The two sample racks 2 of the same specifications are symmetrically arranged on the left and right sides inside the chamber 1. The cross-section of the sample rack 2 is a right triangle. The inclined surface of the sample rack 2 is located in the middle area inside the chamber 1. The sample position 3 is placed on the inclined surface of the sample rack 2. The sample position 3 is distributed at an angle. The structural design of the sample rack 2 is suitable for placing multiple plate samples to ensure that the gas flow uniformly covers the sample surface.

[0023] Specifically, the temperature and humidity sensor 5 is installed inside the upper right of the cabin 1 to monitor environmental parameters in real time and transmit the data to the temperature and humidity display and recording device 6 for real-time display and data recording.

[0024] Specifically, the temperature and humidity display and recording device 6 is installed on the top of the outer side of the cabin 1 so that the operator can view it in real time.

[0025] Specifically, the air circulation device 7 inside the cabin is installed on the top of the inner wall of the cabin 1 to maintain uniform airflow inside the cabin 1 and avoid local concentration differences.

[0026] The formaldehyde environmental chamber equipment also includes a sampling and detection module, a spray cleaning module, and a main control system 12.

[0027] The sampling and detection module, also known as the pollutant background concentration self-monitoring system, is specifically installed on the right side of chamber 1 and connected to the interior of chamber 1 via a silicone hose to achieve real-time gas extraction and background concentration detection. The sampling and detection module includes a sampling port, a miniature air pump, and a gas sensor 4. The sampling port is located on the side wall of chamber 1 and is connected to both the inner and outer walls of chamber 1. The miniature air pump is connected to the sampling port via a conduit. The gas sensor 4 is used to detect formaldehyde and TVOC concentrations.

[0028] The spray cleaning module, also known as the automatic cabin cleaning system, specifically includes a spray cleaning module 8, a liquid collection tank 10, an electromagnetic drain valve 13, and a hot air drying module 11. The spray cleaning module 8 is located at the top of the inner wall of the cabin 1, the liquid collection tank 10 is located at the bottom of the inner wall of the cabin 1, the electromagnetic drain valve 13 is connected to the liquid collection tank 10, and the hot air drying module 11 is located on the side wall of the cabin 1. The spray cleaning module 8 is connected to an external storage tank and a diaphragm pump via pipelines. The hot air drying module 11 includes a PTC heating element and a fan. A liquid level sensor is installed at the bottom of the liquid collection tank 10, and the opening duration of the electromagnetic drain valve 13 is dynamically adjusted by the feedback signal from the liquid level sensor. The working principle of the liquid level sensor is as follows: after spraying, the liquid level sensor detects: when it detects that the liquid level in the collection tank 10 is high, it opens the electromagnetic drain valve 13, and then checks again whether the liquid level in the collection tank 10 has returned to zero. If the liquid level has returned to zero, the drying program is started; if the liquid level has not returned to zero, an alarm and pause process is initiated. When it detects that the liquid level in the collection tank 10 is low, it closes the electromagnetic drain valve 13. The hot air drying module 11 has an air guide channel at the fan outlet, which allows hot air to form a circulating airflow along the side wall of the chamber 1, and the drying temperature is controlled at 45±2℃.

[0029] Specifically, the hot air drying module 11 is installed in the lower right inner wall of the chamber 1. The PTC heating element is arranged in parallel with the fan, and hot air is sent into the chamber 1 through the air guide channel to effectively accelerate the evaporation of surface moisture.

[0030] The liquid collection tank 10 and the electromagnetic drain valve 13 are located in the groove area at the bottom of the inner wall of the chamber 1, and are responsible for collecting the cleaning residue and discharging it to the external collection tank.

[0031] The spray cleaning module 8 includes at least four evenly distributed atomizing nozzles, and the spray direction covers the inner wall of the chamber 1, the sample rack 2 and the liquid collection tank 10.

[0032] When the chamber 1 has a cubic structure, the atomizing nozzles are arranged on the inner walls of the four corners of the top of the chamber 1 in a uniform ring. The atomizing nozzles are externally connected to a storage tank for storing the cleaning fluid, which is supplied by a micro diaphragm pump. To improve the efficiency of pollutant removal, a 3% concentration of hydrogen peroxide solution is added to the spray cleaning fluid to enhance the oxidation reaction capacity. At the same time, an atomizing cleaning auxiliary module 9 is set up.

[0033] Specifically, the formaldehyde environmental chamber equipment also includes an atomizing cleaning auxiliary module 9, which consists of an independent air pump and an atomizing nozzle. The atomizing nozzle is located on the top of the inner wall of the chamber 1 and is used to work with the spray cleaning module 8 to atomize the cleaning liquid, forming a uniform mist that covers the surface of the chamber 1, significantly improving the removal efficiency of background pollutants. The cleaning liquid contains a 3% concentration of hydrogen peroxide solution.

[0034] The main control system 12 is electrically connected to the micro air pump, gas sensor 4, diaphragm pump, electromagnetic drain valve 13, PTC heating element, and fan to execute a closed-loop control process of self-testing, cleaning, draining, drying, and re-testing. Specifically, the gas sensor 4 includes a formaldehyde electrochemical sensor and a TVOC photoionization sensor. The sampling and detection module also includes a silicone tubing, one end of which is connected to the sampling port, and the other end of which is located in the central area inside the chamber 1.

[0035] Specifically, the main control system 12 is located in the control box at the lower right corner or rear of the outer shell of the cabin 1, including a PLC control board, power module, LCD interface and relay terminals, etc., to realize full-process automated linkage control and status monitoring.

[0036] The main control system 12 includes a PLC controller, an LCD display, and a relay group; the PLC controller is pre-programmed with the following logic: responding to the gas sensor 4 detecting a value exceeding the threshold of 0.02 mg / m³. 3 It automatically starts the spray cleaning, drainage, and hot air drying process; after drying is completed, a re-inspection is triggered. If the re-inspection fails, the cleaning process is repeated no more than 3 times; if the standard is still exceeded after the cycle is completed, an alarm signal is output and the door operation authority is locked.

[0037] The specific implementation steps for this formaldehyde environmental chamber equipment are as follows:

[0038] Step 1, System Initialization Phase: The main control system 12 sequentially issues detection commands to each module to confirm the equipment connection status, liquid level sensor status, heating element resistance value, and sensor response curve. After initialization, the sampling and detection module starts, and a miniature air pump draws air from the chamber 1. The gas sensor 4 detects the current formaldehyde and TVOC concentrations and compares them with a set threshold, such as 0.02 mg / m³. 3 Comparison.

[0039] Step 2: If the detected value is lower than the threshold, the system will issue a prompt "Environment meets the standard, the chamber door can be opened". The user can place the sample and close the chamber door within a limited time of 60 to 180 seconds. The system will then automatically record the start time of the test and the initial gas state.

[0040] Step 3: If the detected value exceeds the standard, the system automatically enters the pretreatment process. First, the spray cleaning module 8 is started, and the cleaning solution is sprayed in a clockwise sequence through the top atomizing nozzle. The spraying time is adjusted according to the degree of contamination, ranging from 90 to 120 seconds, to ensure that the inner wall of the chamber 1, the sample rack 2, and the liquid collection tank 10 at the bottom area are covered. During this period, the atomizing cleaning auxiliary module 9 is started simultaneously to atomize 3% hydrogen peroxide solution to generate fine mist, which improves the oxidation efficiency of pollutants. Then, the liquid collection and drainage module is started after a 5-second delay, and the electromagnetic drainage valve 13 is opened to drain the liquid accumulated at the bottom of the chamber. The drainage time is 20 to 40 seconds. The system automatically determines whether the drainage is completed based on the feedback from the liquid level sensor.

[0041] Step 4: After a 10-second system delay, the forced ventilation fan is activated to allow fresh air to flow in at a rate of 10 to 20 L / min for at least 2 minutes, removing residual gas and oxidation byproducts from chamber 1. Then, the hot air drying module 11 is activated, with the heater and fan working together. Hot air is introduced into chamber 1 from the right side and circulated inside for 5 minutes, maintaining a temperature of 45±2℃. After drying, the fan is delayed in turning off to prevent residual heat from accumulating.

[0042] Step 5: After drying is completed, the sampling and detection module is restarted to enter the first retest. If the detection concentration is still not up to standard, the system will automatically perform a second round of spraying, draining, ventilation, drying and retesting. Up to three rounds of closed-loop process can be executed, with an interval of no more than 10 minutes between each round, and the background concentration changes at each stage are recorded.

[0043] Step 6: If all three rounds of re-inspection fail, the LCD display will automatically alarm and prompt "Abnormal background, please intervene manually". The system will pause and lock the operation permission until the administrator confirms and manually resets it. If the second or third round passes, the system will record the cleaning status as "qualified" and prompt that the hatch can be opened for sample delivery.

[0044] This invention adds a sampling and detection module to the standard formaldehyde environmental chamber. By setting up independent sampling ports, a miniature sampling pump, and formaldehyde and TVOC sensors, it enables rapid assessment of the gas state within the chamber 1 before testing, replacing traditional manual sampling and laboratory analysis. Based on the standard formaldehyde environmental chamber, this invention also includes a spray cleaning module, comprising multi-point spray nozzles at the top, a bottom drainage structure, and a hot air drying device on the side walls. This module automatically completes the chamber cleaning, drainage, and drying processes before testing, reducing manual operation and improving cleaning effectiveness. Furthermore, this invention uses a main control system 12 to achieve logical control linkage between sampling and detection, cleaning and drainage, and drying, constructing a closed-loop process of self-inspection, cleaning, drying, and re-inspection. It features automatic judgment, autonomous execution, and abnormal alarm functions, improving the efficiency and reliability of test preparation. Specifically, addressing the technical problems of long detection cycles and high labor costs for background concentration of pollutants in existing technologies, this invention achieves real-time detection and rapid determination of pollutants inside the chamber by setting up a background concentration self-testing module, eliminating the need for external testing and waiting for results, thus greatly improving pretreatment efficiency. Addressing the technical problem of low efficiency due to the need for manual disassembly and cleaning of the chamber in existing technologies, this invention achieves rapid cleaning of the chamber interior through a combination of automatic spraying, automatic drainage, and hot air drying, ensuring cleanliness while saving manpower. Addressing the technical problem of pollutant residue accumulation affecting accuracy under high-frequency testing conditions in existing technologies, this invention introduces an automatic cleaning and re-inspection process, ensuring that the chamber is in a qualified initial state before each test, improving the consistency and reliability of test data.

[0045] The above are merely preferred embodiments of this utility model, but the scope of protection of this utility model is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in this utility model, based on the technical solution and inventive concept of this utility model, should be included within the scope of protection of this utility model.

Claims

1. A formaldehyde environmental chamber device with background concentration self-detection and automatic cleaning functions, characterized in that: The formaldehyde environmental chamber equipment includes a chamber body (1), a sample rack (2) for placing sample positions (3), a temperature and humidity sensor (5) for real-time monitoring of environmental parameters inside the chamber body (1), and an internal air circulation device (7) for maintaining uniform air flow inside the chamber body (1). The formaldehyde environmental chamber equipment also includes a sampling and detection module, a spray cleaning module, and a main control system (12). The sampling and detection module includes a sampling port, a micro air pump, and a gas sensor (4). The sampling port is located on the side wall of the chamber (1) and is connected to the inner and outer walls of the chamber (1). The micro air pump is connected to the sampling port through a conduit. The gas sensor (4) is used to detect the concentration of formaldehyde and TVOC. The gas sensor (4) includes a formaldehyde electrochemical sensor and a TVOC photoionization sensor. The sampling and detection module also includes a silicone hose. One end of the silicone hose is connected to the sampling port, and the other end of the silicone hose is located in the central area inside the chamber (1). The spray cleaning module includes a spray cleaning module (8), a liquid collection tank (10), an electromagnetic drain valve (13), and a hot air drying module (11). The spray cleaning module (8) is located on the top of the inner wall of the chamber (1), the liquid collection tank (10) is located on the bottom of the inner wall of the chamber (1), the electromagnetic drain valve (13) is connected to the liquid collection tank (10), and the hot air drying module (11) is located on the side wall of the chamber (1). The spray cleaning module (8) is connected to an external liquid storage tank and a diaphragm pump through pipelines. The hot air drying module (11) includes a PTC heating element and a fan. The main control system (12) is electrically connected to the micro air pump, the gas sensor (4), the diaphragm pump, the electromagnetic drain valve (13), the PTC heating element and the fan; The spray cleaning module (8) includes at least four evenly distributed atomizing nozzles, and the spray direction covers the inner wall of the chamber (1), the sample rack (2) and the liquid collection tank (10); The formaldehyde environmental chamber equipment also includes an atomizing cleaning auxiliary module (9), which consists of an independent air pump and an atomizing nozzle. The atomizing nozzle is arranged on the top of the inner wall of the chamber (1) and is used to work in conjunction with the spray cleaning module (8) to atomize the cleaning liquid.

2. The formaldehyde environmental chamber equipment with background concentration self-detection and automatic cleaning functions according to claim 1, characterized in that: The hot air drying module (11) has a fan outlet with an air guide channel, so that hot air forms a circulating airflow along the side wall of the cabin (1).

3. The formaldehyde environmental chamber equipment with background concentration self-detection and automatic cleaning functions according to claim 1, characterized in that: The liquid collection tank (10) is equipped with a liquid level sensor at the bottom, and the opening duration of the electromagnetic drain valve (13) is dynamically adjusted by the feedback signal of the liquid level sensor.

4. The formaldehyde environmental chamber equipment with background concentration self-detection and automatic cleaning functions according to claim 1, characterized in that: The cabin (1) adopts a double-layer heat insulation structure, with the outer shell being galvanized steel plate and the inner lining being polished stainless steel.

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