Radioactive aerosol continuous monitor

Abstract

The utility model discloses a kind of radioactive aerosol continuous monitoring instrument, it is related to environmental radioactivity monitoring field, comprising: box, the box top upper and lower communication is equipped with air inlet component and radiation measurement component;Filter membrane operating unit, the filter membrane operating unit includes guiding wheel below air outlet and filter membrane horizontal transmission on guiding wheel;The sampling unit includes the piston that can be vertically active below filter membrane and the driving assembly that can drive piston, the piston upper end is equipped with the airflow chamber of top opening and airflow chamber opening is equipped with sealing ring;Air pump unit.The utility model realizes the automatic transmission of filter membrane by filter membrane operating unit, in combination with piston ascending in sampling unit, filter membrane is pressed tightly in the air outlet of measurement component, effectively solve the core problem of poor tightness and low positioning accuracy of traditional roll film structure, ensure that every sampling point can be carried out under sealed condition, avoid the measurement error caused by air leakage.

Description

Technical Field

[0001] This utility model relates to the field of environmental radioactivity monitoring, specifically to a continuous radioactive aerosol monitoring instrument. Background Technology

[0002] Radioactive aerosols are a key monitoring indicator that may be released into the environment during the operation of nuclear facilities, the application of nuclear technology, and sudden nuclear accidents. Continuous, automated, and reliable monitoring of these aerosols is an important means of protecting public health and environmental safety. The core working principle of a continuous radioactive aerosol monitor is to draw in ambient air using an air pump, causing aerosol particles to be trapped on a filter membrane, and then using a radiation detector to measure the radioactivity collected on the filter membrane in real time.

[0003] Currently, the main technical challenges in achieving long-term unattended continuous monitoring lie in the replacement and positioning methods of the filter membrane. Traditional monitoring instruments mostly employ two solutions: fixed filter membrane type, where the device uses a single large filter membrane for continuous sampling over long periods. While simple in structure, the filter membrane pores gradually become clogged with particulate matter during sampling, leading to a decrease in sampling flow rate, distorted measurement results, and an inability to guarantee long-term measurement accuracy. The other solution is a simple roll-up membrane type, where some devices attempt to address the continuous monitoring problem by using a roll-up filter membrane, with the sampling point being changed via a motor-driven winding mechanism.

[0004] However, existing roll-up membrane structures have the following drawbacks: poor sealing, with incomplete sealing between the filter membrane and the measurement chamber during sampling, resulting in air leakage around the perimeter. This causes some aerosol-containing air to leak directly without passing through the filter membrane, making the collected samples unrepresentative and leading to significantly lower measurement results; low positioning accuracy, with a simple filter membrane delivery mechanism lacking precise spacing control. This results in large measurement errors, affecting the comparability and reliability of the data.

[0005] Therefore, there is an urgent need for a continuous radioactive aerosol monitoring instrument that can achieve automatic filter membrane delivery, consistent membrane sampling spacing, and reliable sealing during sampling. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the aforementioned background technology and provide a continuous radioactive aerosol monitoring instrument with automatic filter membrane delivery, consistent membrane sampling spacing, and reliable sealing during sampling.

[0007] The technical solution of this utility model is: a continuous radioactive aerosol monitoring instrument, comprising: The box body has an air intake component for airflow and a radiation measurement component for measuring the sampled aerosol installed on the top and bottom of the box body. The bottom of the radiation measurement component has an air outlet for gas to flow downwards. The filter membrane operation unit includes guide wheels arranged on the left and right sides below the air outlet and a filter membrane horizontally transported on the guide wheels. It also includes a membrane supply assembly and a membrane spacing control assembly arranged on one side of the housing, and a membrane collection assembly arranged on the other side. The sampling unit includes a vertically movable piston located below the filter membrane and a drive assembly that can drive the piston to move vertically. The upper end of the piston is provided with an airflow chamber with a top opening and a sealing ring is provided at the opening of the airflow chamber. When sampling, the piston moves upward so that the sealing ring presses the filter membrane against the air outlet. An air pump unit, the inlet of which is connected to the airflow chamber for air extraction and sampling.

[0008] Preferably, the air intake assembly includes an internally hollow air intake chamber, the top of the air intake chamber is provided with an air inlet communicating with the atmosphere and an electromagnetic shielding mesh is embedded inside, and a temperature and humidity module is installed inside the air intake chamber below the electromagnetic shielding mesh.

[0009] Furthermore, the radiation measurement assembly includes a hollow radiation measurement chamber, a detector inside the radiation measurement chamber, and an air outlet located at the bottom of the radiation measurement chamber and directly below the detector.

[0010] In some embodiments, before sampling, the device performs calibration tests on the temperature and humidity module, detector sensor, and filter membrane; specifically, the device is started and operation is disabled, the air pump unit is stopped, the temperature and humidity module, detector, etc. are started and operation is performed, the filter membrane operates under pollution-free conditions, and then the initialization data of the temperature and humidity module and detector are obtained.

[0011] Preferably, the housing has a vertical equipment mounting plate behind the filter membrane. One side of the front panel of the equipment mounting plate is provided with a membrane supply assembly and a membrane spacing control assembly, and the other side of the front panel is provided with a membrane take-up assembly. The membrane supply assembly includes a first expansion shaft rotatably connected to the equipment mounting plate. The first expansion shaft is used to pass through the filter membrane roll and a first baffle is provided on the first expansion shaft to restrict the axial movement of the filter membrane roll. A brake is provided on the back of the equipment mounting plate and connected to the rear end of the first expansion shaft to form a constant tension of the filter membrane.

[0012] Furthermore, the membrane spacing control component is disposed between the membrane supply component and the guide wheel on the same side. The membrane spacing control component includes a detection wheel rotatably connected to the equipment mounting plate. An encoder is provided on the back of the equipment mounting plate and connected to the rear end of the detection wheel for measuring the movement distance of the filter membrane.

[0013] In some embodiments, an auxiliary clamping wheel is also included, which clamps the filter membrane drawn out from the membrane assembly onto the detection wheel.

[0014] Furthermore, the membrane recovery assembly includes a second expansion shaft rotatably connected to the equipment mounting plate. The second expansion shaft is used to roll up the recovered filter membrane, and a second baffle is provided on the second expansion shaft to restrict the axial movement of the recovered filter membrane roll. A recovery motor is provided on the back of the equipment mounting plate and connected to the rear end of the second expansion shaft to drive the second expansion shaft to rotate.

[0015] Furthermore, the sampling unit also includes a sampling housing disposed on the front panel of the equipment mounting plate. The driving assembly includes a motor driving assembly fixedly mounted on the lower end of the sampling housing. An axial bearing is provided in the middle of the sampling housing. The piston is connected to the inner ring of the axial bearing, restricting its movement only vertically on the sampling housing. The bottom of the piston is connected to the output shaft of the motor driving assembly via a curve-to-straight-line module. It is understood that in the embodiment, the driving assembly includes a motor and a reducer connected to the output shaft of the motor.

[0016] The curve-to-straight-line module includes a tubular bushing connected to the output shaft of the motor drive assembly. The bushing has a spiral groove on its side wall. The lower end of the piston extends into the bushing and has a protruding positioning pin that enters the spiral groove, which is used to drive the piston to move vertically when the output shaft of the motor drive assembly rotates.

[0017] In some embodiments, the vertical groove spacing of the spiral grooves is greater than the diameter of the positioning pin; it also includes a spring, the upper end of which abuts against the bottom of the airflow chamber, and the lower end of which abuts against the supporting surface of the sampling housing.

[0018] Preferably, the piston has a honeycomb mesh embedded within the sealing ring, and the top surface of the sealing ring is higher than the honeycomb mesh. More preferably, the top surface of the sealing ring is also slightly higher than the top surface of the airflow chamber.

[0019] Preferably, the air pump unit includes an air inlet pipe, an air pump, and an air pump drive module. The inlet end of the air inlet pipe is connected to a piston exhaust port on the airflow chamber, and the outlet end is connected to the inlet end of the air pump. The air pump drive module is used to control the air pump to draw air for sampling. The outlet end of the air pump leads to an exhaust port on the housing.

[0020] Preferably, it also includes a radioactivity level analysis multichannel module installed inside the enclosure, which is connected to the detector signal for analyzing the radionuclide mass level of aerosols.

[0021] Preferably, the radioactive aerosol continuous monitoring instrument further includes a measurement and control unit, which is signal-connected to and controls the air intake assembly, radiation measurement assembly, filter membrane operation unit, sampling unit, and air pump unit. The equipment mounting plate is also equipped with a "one-click membrane replacement" button and a membrane replacement indicator light, both of which are connected to the measurement and control unit. The "one-click membrane replacement" button is used to control the piston to descend when preparing for manual membrane replacement, and the measurement and control unit controls the membrane replacement indicator light to light up when it descends to the stop point. After the membrane replacement is completed, the measurement and control unit controls the membrane replacement indicator light to turn off.

[0022] The beneficial effects of this utility model are as follows: 1. This utility model achieves automatic conveying of the filter membrane through the filter membrane running unit. Combined with the piston rising in the sampling unit to press the filter membrane against the air outlet of the measuring component, it effectively solves the core problems of poor sealing and low positioning accuracy of traditional roll-up membrane structures, ensuring that each sampling point can be carried out in a sealed state and avoiding measurement errors caused by air leakage.

[0023] 2. Since the filter membrane operation unit can deliver a new filter membrane after each measurement, it avoids the sampling flow rate attenuation problem caused by particulate matter blockage of a single fixed filter membrane. It can achieve long-term unattended continuous monitoring, and the flow rate is constant in each sampling cycle, ensuring the accuracy and comparability of the measurement results.

[0024] 3. The air intake assembly is equipped with an electromagnetic shielding mesh and a temperature and humidity module, which can eliminate external electromagnetic interference and monitor air intake conditions, providing a basis for data correction; while the air pump unit is placed after the filter membrane and the measuring assembly, making the entire sampling airflow path a "top-down" negative pressure design, which helps to prevent some pollutants inside the chamber from flowing back and contaminating the detector, improving the reliability of the equipment in complex environments.

[0025] 4. By setting up a membrane spacing control component consisting of an encoder, a detection wheel, and an auxiliary clamping wheel, the movement distance of the filter membrane can be accurately measured and controlled, ensuring that the spacing of each sampling point is consistent. This avoids measurement errors caused by inaccurate positioning and greatly improves the comparability and reliability of the data.

[0026] 5. The membrane supply assembly is equipped with a brake to provide constant membrane tension, and the membrane take-up assembly is actively wound by a motor. The two work together to ensure that the filter membrane is always in a taut and flat state during the transmission process. This not only facilitates accurate positioning, but also ensures the uniformity of the filter membrane and sealing ring pressing during sampling, further improving the sealing effect.

[0027] 6. The drive assembly uses a motor and reducer, and an innovative curve-to-linear conversion module transforms rotary motion into linear piston motion. This ingenious design results in high transmission efficiency, smooth movement, and precise control of the piston's lifting and lowering stroke and clamping force, achieving automation and precise control of the sampling process.

[0028] 7. The top surface of the sealing ring is higher than the honeycomb mesh, so that when compressed, the sealing ring contacts the filter membrane first and undergoes elastic deformation to achieve a seal. The honeycomb mesh then supports the filter membrane and prevents it from excessively deforming or tearing. This design ensures excellent sealing performance while reducing the risk of damage to the fragile filter membrane.

[0029] 8. The design of the radiation measurement chamber allows the detector to be directly aligned with the sampling point (filter membrane), and measurements can be performed directly after sampling without moving the filter membrane. This shortens the time interval between sampling and measurement, which is beneficial for detecting short-lived nuclides, reduces measurement efficiency loss due to distance, and improves detection sensitivity.

[0030] 9. It integrates a multi-channel module for radioactivity level analysis, which can be used in conjunction with the detector to perform energy spectrum analysis and nuclide identification on the collected aerosol samples directly on site, realizing full automation and intelligence from sampling and measurement to data analysis, and timely outputting nuclide quality information to provide direct basis for environmental safety assessment.

[0031] 10. By setting up a "one-click membrane replacement" function, the originally complex membrane replacement process (such as manual membrane traction and piston positioning) is simplified to a single-button operation, significantly reducing the skill requirements and labor intensity of operators, making the membrane replacement process fast and convenient. The on / off status of the membrane replacement indicator light provides operators with a clear and intuitive indication of the membrane replacement progress, ensuring the accuracy of the membrane replacement process and the safety of the equipment. Attached Figure Description

[0032] Figure 1 A 3D view of the front of a continuous radioactive aerosol monitor (front door omitted). Figure 2 A 3D view of the back of a continuous radioactive aerosol monitor (backdoor omitted). Figure 3 A three-dimensional diagram of a continuous radioactive aerosol monitor (inlet chamber omitted). Figure 4 Right view of a radioactive aerosol continuous monitoring instrument Figure 5 A schematic diagram of the vertical structure of the air intake assembly, radiation measurement assembly, and sampling unit. Figure 6 A frontal perspective view of a radioactive aerosol continuous monitoring instrument. Wherein: 1-Sampling unit 2-Airflow chamber 3-Second baffle 4-Second expansion shaft 5-Guide wheel (5.1-Auxiliary guide wheel) 6-Inlet chamber 7-Inlet 8-Alarm light 9-Filter membrane 10-Detection wheel 11-Auxiliary clamping wheel 12-First baffle 13-First expansion shaft 14-Spiral groove 15-Positioning pin 16-"One-key membrane replacement" key 17-Membrane replacement indicator light 18-Air pump bracket 19-Exhaust port 20-Power supply 21-Air pump 22-Air pump drive module; 30-Encoder; 31-Brake; 32-Measurement and Control Unit; 33-Wire Groove; 34-Exhaust Pipe; 35-Intake Pipe; 36-Recovery Motor Bracket; 37-Recovery Motor; 38-Flow Measurement Module Housing; 39-Equipment Mounting Plate. 41-Radioactivity level analysis multichannel module; 42-Flow signal module; 43-Gas filter module; 46-Handle; 47-Hinge; 48-Network interface; 49-Power interface; 50 - Exhaust port; 51 - Communication interface one; 52 - Communication interface two; 53 - Power fuse; 54 - Power switch; 55 - Lock; 58 - Electromagnetic shielding mesh; 59 - Temperature and humidity module; 60-Mounting bracket; 61-Detector; 63-Sealing ring; 64-Cellular mesh; 65-Piston; 66-Piston exhaust port; 67-Spring; 68-Sampling housing; 69-Shaft sleeve; 70-Axial bearing; 71-Reducer; 72-Motor; 73-Radiation measurement chamber; 74-Air outlet; 80 - Display and microprocessor; 81 - Indicator light; 82 - Button; 100 - Cabinet. Detailed Implementation

[0033] The embodiments of this utility model are described in detail below, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0034] In the description of this utility model, it should be understood that the terms "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to 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 utility model.

[0035] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0036] like Figures 1-6As shown, the present invention provides a continuous radioactive aerosol monitor, comprising a housing 100 that can be opened from both the front and back. The interior of the housing 100 is divided into a front operating space and a rear equipment space by a vertically arranged equipment mounting plate 39. The equipment mounting plate 39 is the core support structure of the entire instrument, and all functional modules are mounted on it.

[0037] The top of the enclosure 100 is equipped with an air intake assembly for airflow and a radiation measurement assembly for measuring the sampled filter membrane. The radiation measurement assembly has a downward-facing air outlet 74 at its bottom. The air intake assembly is connected to the upper surface of the top plate of the enclosure 100 and has the following structure: it includes a hollow air intake chamber 6 with an air inlet 7 at its top that connects to the atmosphere. Inside the air intake chamber 6, from top to bottom, are embedded an electromagnetic shielding mesh 58 and a temperature and humidity module 59. The electromagnetic shielding mesh 58 is used to shield against external electromagnetic interference, ensuring the stable operation of electronic components; the temperature and humidity module 59 is used to monitor the temperature and humidity parameters of the incoming air in real time, providing environmental data for flow correction and data processing.

[0038] The radiation measurement assembly is connected to the bottom of the top plate inside the housing 100 and includes a hollow radiation measurement chamber 73 located directly below the air inlet chamber 6. A detector 61 is installed inside the radiation measurement chamber 73. An air outlet 74 is located at the center of the bottom of the radiation measurement chamber 73, directly below the detector 61. The air outlet 74 and the detector 61 are coaxially aligned, and the diameter of the air outlet is slightly smaller than the outer diameter of the detector 61. A radioactivity level analysis multichannel module 41 is also installed on the left inner wall of the housing 100. The signal output terminal of the detector 61 is connected to the radioactivity level analysis multichannel module 41, which analyzes the collected radiation spectrum, identifies nuclides, and calculates activity concentration.

[0039] In a preferred embodiment, an opening is provided on the top plate of the housing 100, with the lower end of the air intake chamber 6 open and the upper end of the measurement chamber 73 open. The two are connected vertically to the openings on the top plate (the upper end of the measurement chamber 73 is connected to the opening, and the lower end of the air intake chamber 6 is fixed to the edge of the opening with the opening inside), thereby realizing the vertical connection and installation of the air intake component and the radiation measurement component. The temperature and humidity module 59 and the detector 61 can be installed by setting brackets in the air intake chamber 6 and the measurement chamber 73 respectively, or they can be installed by setting an integrated mounting bracket 60. The integrated mounting bracket 60 can be set as an inverted Ω shape, with the recessed central bottom surface used to install the detector 61, and the horizontally protruding parts at both ends used to install the temperature and humidity module 59. The two ends of the mounting bracket 60 are fixedly connected to the measurement chamber 73.

[0040] The membrane transport unit is the core component for the automatic transport and positioning of the filter membrane 9. The membrane transport unit includes guide wheels 5 positioned on the left and right sides below the air outlet 74, and the filter membrane 9 horizontally transported on the guide wheels 5. It also includes a membrane supply assembly, a membrane collection assembly, and a membrane spacing control assembly. The membrane supply assembly and membrane spacing control assembly are located on the right side of the front panel of the equipment mounting plate 39, while the membrane collection assembly is located on the left side of the front panel of the equipment mounting plate 39 (e.g., [missing information]). Figure 1 (As shown).

[0041] There are two guide rollers 5. The filter membrane 9 is led out from the membrane supply assembly, passes through the auxiliary guide roller 5.1 located to the right of the membrane spacing control assembly, goes around the top of the right guide roller 5, passes horizontally through the sampling area, goes around the top of the left guide roller 5, and is finally wound up by the membrane take-up assembly. The guide rollers 5 ensure that the filter membrane 9 remains horizontal and flat in the sampling area.

[0042] The film supply assembly is located on the upper right side of the front panel of the equipment mounting plate 39. Figure 1 (As shown). It includes a first expansion shaft 13, the end of which is rotatably connected to the equipment mounting plate 39 via a bearing. The first expansion shaft 13 is used to mount unused roll-shaped filter membrane 9. A first baffle 12 on the shaft is used to limit the axial movement of the filter membrane roll. On the back of the equipment mounting plate 39, a brake 31 is mounted, which is connected to the rear end of the first expansion shaft 13, providing constant resistance during the membrane unwinding process, thereby ensuring that the filter membrane 9 remains taut throughout the transport process. In a preferred embodiment, there are two first baffles 12, which limit the movement at the front and rear end faces of the roll-shaped filter membrane 9.

[0043] The membrane take-up assembly is located on the left side of the front panel of the equipment mounting plate 39. It includes a second expansion shaft 4, which is also rotatably connected to the equipment mounting plate 39 via bearings. The second expansion shaft 4 is power-driven and used to take up the sampled filter membrane 9. A second baffle 3 on the shaft is used to restrict the axial movement of the recycled filter membrane roll. On the back of the equipment mounting plate 39, a recycling motor 37 (such as a stepper motor or servo motor) is mounted via a recycling motor bracket 36, which is connected to the rear end of the second expansion shaft 4 via a coupling, providing active tension for the transport of the filter membrane 9. In a preferred embodiment, there are two second baffles 3, which limit the movement at the front and rear end faces of the recycled filter membrane roll.

[0044] The membrane spacing control assembly is located on the filter membrane path between the membrane supply assembly and the right-side guide wheel 5, and includes a detection wheel 10 and an auxiliary pressing wheel 11. The detection wheel 10 is rotatably connected to the equipment mounting plate 39, and the auxiliary pressing wheel 11 elastically presses the filter membrane 9 against the circumferential surface of the detection wheel 10, ensuring that the filter membrane 9 can reliably drive the detection wheel 10 to rotate when it moves. On the back of the equipment mounting plate 39, a high-precision encoder 30 is installed, which is coaxially connected to the rear end of the rotating shaft of the detection wheel 10. The linear movement distance of the filter membrane 9 is accurately converted into the number of rotations of the detection wheel 10, and the encoder 30 records the number of pulses, thereby realizing precise closed-loop control of the filter membrane 9 transmission distance and ensuring the consistency of the spacing between each sampling point.

[0045] The sampling unit 1 is the key actuator for achieving the compression sealing of the filter membrane 9 and sampling. It includes a piston 65, a drive assembly, and a sampling housing 68 fixed to the equipment mounting plate 39. The piston 65 and the drive assembly are installed inside the sampling housing 68. The upper end of the piston 65 has an airflow chamber 2 with a top opening. A sealing ring 63 is embedded in the opening of the airflow chamber 2, and a honeycomb mesh 64 is also provided inside the sealing ring 63. Crucially, the top surface of the sealing ring 63 is slightly higher than the top surface of the honeycomb mesh 64 and also slightly higher than the top surface of the airflow chamber 2. When the piston 65 rises, the sealing ring 63 first contacts the filter membrane 9 above and undergoes elastic deformation to form a reliable seal, while the honeycomb mesh 64 supports the filter membrane 9, preventing it from being sucked into the airflow chamber 2 or from being damaged due to excessive pressure.

[0046] The drive assembly, used to precisely raise and lower the piston 65, includes a motor 72 (motor drive assembly) fixedly mounted at the lower end of the sampling housing 68 and a reducer 71 connected to the motor's output shaft. The reducer 71 is connected to the upward-facing output shaft of the motor 72. An axial bearing 70 is mounted in the middle of the sampling housing 68, and the piston 65 is fixedly connected to the inner ring of this bearing 70, thus restricting its movement to vertical linear motion only. The bottom of the piston 65 is connected to the output shaft of the reducer 71 via a curve-to-linear conversion module.

[0047] The specific structure of the curve-to-straight-line module includes: a tubular bushing 69 connected to the upper output shaft of the reducer 71. A helical groove 14 is machined on the side wall of the bushing 69. The lower end of the piston 65 extends into the bushing 69 and has a protruding locating pin 15, which fits precisely into the helical groove 14. When the motor 72 drives the bushing 69 to rotate through the reducer 71, the locating pin 15, constrained by the helical groove 14, converts the rotational motion of the bushing 69 into the precise linear lifting and lowering motion of the piston 65.

[0048] In some preferred embodiments, the airflow chamber 2 is coaxially arranged with the piston 65 and its outer diameter is larger than the diameter of the piston 65 body, forming a flange structure. A spring 67 is provided above the axial bearing 70 on the piston 65. The upper end of the spring 67 is connected to the bottom of the airflow chamber 2, and the lower end is connected to the sampling housing 68. The upper end of the spring 67 abuts against the bottom of the airflow chamber 2 (the bottom surface of the flange structure), while the lower end is supported on the support surface of the sampling housing 68. When the piston 65 rises to press the filter membrane, the rigid thrust provided by the drive assembly is converted into a flexible, adaptive pressing force by the spring 67. The vertical groove spacing of the spiral groove 14 is slightly larger than the diameter of the locating pin 15, allowing the locating pin 15 a small vertical movement space in the spiral groove 14, avoiding rigid interference between the locating pin 15 and the groove wall of the spiral groove 14 when the spring 67 adjusts the pressing. Even with minor errors in machining or assembly, the spring 67 can ensure that the pressure applied to the filter membrane 9 and the sealing ring 63 is uniform and stable through its own compression deformation, avoiding the problem of overpressure damaging the filter membrane or underpressure causing poor sealing.

[0049] The air pump unit generates the sampling airflow and includes an inlet pipe 35, an air pump 21, and an air pump drive module 22. The inlet end of the inlet pipe 35 communicates with a piston exhaust port 66 on the airflow chamber 2 of the piston 65, and the outlet end communicates with the inlet end of the air pump 21. The piston exhaust port 66 is located at the rear of the airflow chamber 2, and the inlet pipe 35 is located behind the equipment mounting plate 39, passing through a corresponding hole on the equipment mounting plate 39 and connecting to the piston exhaust port 66 of the airflow chamber 2. The outlet end of the air pump 21 is connected to an exhaust pipe 34 via an exhaust port 19. The exhaust pipe 34 leads to an exhaust port 50 on the side wall of the housing 100, discharging filtered clean air. The air pump 21 is mounted inside the housing 100 in the lower middle section via an air pump bracket 18.

[0050] The radioactive aerosol continuous monitoring instrument of this invention also includes a measurement and control unit 32, which is the main control component. It is signal-connected to and controls the air intake assembly, radiation measurement assembly, filter membrane operation unit, sampling unit, and air pump unit. The measurement and control unit 32 can be a measurement and control module (e.g., Figure 2 A rectangular block-shaped measurement and control module placed horizontally in the middle of the housing (or multiple measurement and control modules connected together to form a unit, such as...) Figure 2 The control unit 32 is a rectangular block-shaped measurement and control module placed horizontally in the middle of the housing, and also includes a rectangular block-shaped measurement and control module placed vertically on the inner wall of the left side of the housing. The measurement and control unit 32 is connected to the radioactivity level analysis multichannel module 41 via signal connection.

[0051] In a preferred embodiment, a flow signal module 42 is provided between the air inlet pipe 35 and the air pump 21 for flow signal measurement. The flow signal module 42 is signal-connected to the gas filter module 43 to filter the flow signal to obtain a stable flow signal. The gas filter module 43 is signal-connected to the measurement and control unit 32 to transmit the filtered flow signal to the measurement and control unit 32. The measurement and control unit 32 controls the air pump drive module 22, which drives the air pump 21 to maintain constant flow sampling. A flow measurement module housing 38 is mounted on the back of the equipment mounting plate 39, and the flow signal module 42 and the gas filter module 43 are installed inside the flow measurement module housing 38.

[0052] In a preferred embodiment, power supply and communication are essential functions of this utility model device. The power supply 20 is installed in the lower part of the housing 100 to power the device. Handles 46 are installed on the left and right sides of the outer wall of the housing 100. Hinges 47 are provided on the front and rear doors of the housing 100 for opening and closing. The right side panel of the housing 100 includes a network interface 48, an input power interface 49, an exhaust port 50 of the air pump 21, two communication interfaces (communication interface one 51 and communication interface two 52), a power fuse 53, and a power switch 54. Locks 55 are provided on both the front and rear doors, two sets each. All wires of the radioactive aerosol continuous monitoring instrument are housed in a wire trough 33, which is horizontally positioned at the lower rear of the housing 100. The front door of the housing 100 is equipped with a display and microprocessor 80 that displays test results and allows for setting test parameters. The display and microprocessor 80 are connected to the measurement and control unit 32. The display and microprocessor 80 also includes indicator lights 81 and buttons 82. Buttons 82 are used for setting test parameters, and indicator lights 81 are used to display the instrument's operating status.

[0053] In a preferred embodiment, the top of the enclosure 100 is also provided with an alarm light 8, which is connected to the display and microprocessor 80 and the measurement and control unit 32. The alarm light 8 flashes when the radioactivity level exceeds a preset threshold.

[0054] In a preferred embodiment, a "one-click membrane replacement" button 16 and a membrane replacement indicator light 17 are provided on the front panel of the equipment mounting plate 39 below the membrane supply assembly, both of which are connected to the measurement and control unit 32 via signals. When the filter membrane roll is used up, press the "One-click membrane change" button 16. The measurement and control unit 32 controls the sampling unit 1 to descend to the stop point, and the membrane change indicator light 17 lights up. Manual membrane change begins. First, install the filter membrane 9 in the first expansion shaft 13 of the membrane supply assembly and install the first baffle 12. Then, manually pull the filter membrane 9 through the auxiliary guide wheel 5.1, circle the membrane spacing control component detection wheel 10 half a turn, continue to move upward through the right guide post 5, the top of the sampling unit 1, and the left guide post 5. Then, move downward to the second expansion shaft 4 of the membrane take-up assembly, circle the second expansion shaft 4 twice, and install the second baffle 3. Press the "One-click membrane change" button 16 again. At this time, the membrane change indicator light 17 goes out. After the membrane change indicator light 17 goes out, press the auxiliary clamping wheel 11 to clamp the membrane spacing control component detection wheel 10, indicating that the membrane change is complete. At this time, click "Start Sampling" on the display and microprocessor 80 or the measurement and control unit 32 display screen. The recovery motor 37, encoder 30, and brake 31 work, and the equipment enters the automatic monitoring mode.

[0055] After one-click membrane replacement, background calibration is required. Click the background calibration button on the display and microprocessor 80. The measurement and control unit 32 will automatically control the sampling unit 1 to work, the membrane receiving assembly recovery motor 37 to work, the membrane supply assembly brake 31 to work, the membrane spacing control component encoder 30 to work, the radioactivity level analysis multichannel module 41 to work, and the aerosol pump 21 to stop working in a fully automatic mode. After the background calibration is completed, press the background calibration button again and the system will work normally.

[0056] After background calibration, the monitor enters calibration mode. That is, when the calibration button is pressed on the display and microprocessor 80, the measurement and control unit 32 automatically controls the sampling unit 1 to descend to the stop point and then stops working. The staff places the radiation source into the top of the sampling unit 1. The membrane recovery motor 37, the membrane supply brake 31, the membrane spacing control encoder 30, and the aerosol pump 21 stop working. The radioactivity level analysis multichannel module 41 operates in fully automatic mode. After calibration is completed, press the calibration button again, and the system will work normally.

[0057] The working principle of this utility model is as follows: 1. Initial Preparation and Precise Positioning: When a new sampling cycle needs to begin, the measurement and control unit 32 first instructs the membrane receiving assembly to operate, starting the recovery motor 37 and driving the second expansion shaft 4 to rotate, thereby pulling the filter membrane 9 smoothly from the membrane supply assembly (first expansion shaft 13) towards the membrane receiving direction. Simultaneously with the start of the recovery motor 37, the brake 31 is activated, pressing the filter membrane 9 and causing the detection wheel 10 in the membrane spacing control assembly to rotate. The encoder 30, coaxially connected to the wheel, precisely measures the number of pulses moving the filter membrane in real time. When the moving distance reaches the preset, precise spacing that ensures no overlap of sampling points, the measurement and control unit 32 stops the recovery motor 37. At this point, a clean section of filter membrane 9 is precisely conveyed and positioned between the air outlet 74 at the bottom of the radiation measurement module 73 and the sampling head 1.

[0058] 2. Seal establishment and constant current sampling After the filter membrane is positioned, the measurement and control unit 32 instructs the sampling unit to operate, and the motor 72 drives the piston 65 upward through the reducer 71 and the curve-to-linear conversion module 69. The sealing ring 63 on the top of the piston 65 rises accordingly, pressing the filter membrane 9 tightly against the air outlet at the bottom of the radiation measurement module 73, forming a sealed sampling chamber. Subsequently, the air pump unit starts: the air pump 21 starts working under the control of the air pump drive module 22, generating a constant flow of intake air in the sampling pipeline.

[0059] Ambient air enters through inlet 7, flows sequentially through electromagnetic shielding mesh 58, temperature and humidity module 59, and radiation measurement chamber (surrounding detector 61), and finally passes downwards through the compressed filter membrane 9. During this process, radioactive aerosol particles in the air are efficiently trapped on the surface of filter membrane 9. Clean air continues downwards, passing through airflow chamber 2 of the sampling unit, piston exhaust port 66, and inlet pipe 35, and is finally discharged through exhaust port 50 via air pump 21.

[0060] 3. In-situ measurement and data analysis: After a preset sampling time, the air pump 21 stops. Since the filter membrane 9 remains pressed in place, optimal measurement conditions are maintained between the radioactive nuclides collected on its surface and the detector 61. The detector 61 converts the radiation generated by the decay of the nuclides on the filter membrane into a signal, which is transmitted to the radioactivity level analysis multichannel module 41 for energy spectrum analysis. The analysis results are displayed and stored by the measurement and control unit 32 to the display and microprocessor 80, and an alarm is triggered based on a preset threshold. Simultaneously, the data can be uploaded to a remote data center via the network interface 48.

[0061] 4. Filter Membrane Transfer and Cyclic Monitoring: After measurement, the system enters the filter membrane transfer procedure. The control unit 32 instructs the motor 72 of sampling head 1 to reverse, driving piston 65 to descend and releasing the pressure on filter membrane 9. Subsequently, the precise positioning process of step 1 is repeated, and the recovery motor 37 starts again, winding the sampled and measured filter membrane segment onto the second expansion shaft 4 of the membrane take-up assembly for storage, while simultaneously precisely transferring the next clean filter membrane segment to the sampling position. Afterward, the system automatically repeats steps 2 and 3, starting a new round of sampling-measurement cycle, thereby achieving truly long-term, unattended continuous monitoring.

[0062] In the above measurements, the combination of encoder 30 and detection wheel 10 ensures that the spacing between each sampling point is consistent; the piston 65 driven by curve to straight line module 69 and its top sealing ring 63 structure can form a reliable sealing surface during each sampling, completely solving the air leakage problem of traditional roll film equipment; the entire process of positioning-pressing-sampling-measuring-transfer is automatically controlled by measurement and control unit 32 without manual intervention, meeting the requirements of unattended operation.

[0063] The above description is merely a preferred embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. A continuous monitor of radioactive aerosols, characterized in that, include: The box (100) has an air inlet assembly for airflow and a radiation measurement assembly for measuring the sampled aerosol installed on the top and bottom of the box (100). The bottom of the radiation measurement assembly has an air outlet (74) for gas to flow downward. The filter membrane operation unit includes guide wheels (5) arranged on the left and right sides below the air outlet (74) and a filter membrane (9) horizontally transported on the guide wheels (5). It also includes a membrane supply assembly and a membrane spacing control assembly arranged on one side of the housing (100) and a membrane collection assembly arranged on the other side. The sampling unit (1) includes a vertically movable piston (65) located below the filter membrane (9) and a driving assembly that can drive the piston (65) to move vertically. The piston (65) has an airflow chamber (2) with a top opening at the upper end and a sealing ring (63) at the opening of the airflow chamber (2). When sampling, the piston (65) moves upward so that the sealing ring (63) presses the filter membrane (9) onto the air outlet (74). An air pump unit, the inlet of which is connected to the airflow chamber (2) for air extraction and sampling.

2. The continuous monitor of radioactive aerosols according to claim 1, characterized in that, The air intake assembly includes an internally hollow air intake chamber (6), the top of which is provided with an air inlet (7) that communicates with the atmosphere and an electromagnetic shielding mesh (58) is embedded inside. A temperature and humidity module (59) is installed inside the air intake chamber (6) below the electromagnetic shielding mesh (58). The radiation measurement assembly includes a hollow radiation measurement chamber (73), a detector (61) inside the radiation measurement chamber (73), and an air outlet (74) located at the bottom of the radiation measurement chamber (73) and directly below the detector (61).

3. The continuous monitor for radioactive aerosols as claimed in claim 1, wherein, The housing (100) has a vertical equipment mounting plate (39) behind the filter membrane (9). One side of the front panel of the equipment mounting plate (39) is provided with a membrane supply assembly and a membrane spacing control assembly, and the other side of the front panel is provided with a membrane receiving assembly. The membrane supply assembly includes a first expansion shaft (13) rotatably connected to the equipment mounting plate (39). The first expansion shaft (13) is used to thread the filter membrane roll, and a first baffle (12) is provided on the first expansion shaft (13) to restrict the axial movement of the filter membrane roll. A brake (31) is provided on the back of the equipment mounting plate (39) and connected to the rear end of the first expansion shaft (13) to form a constant tension of the filter membrane.

4. A continuous monitor for radioactive aerosols as claimed in claim 3, characterised in that, The membrane spacing control component is located between the membrane supply component and the guide wheel (5) on the same side. The membrane spacing control component includes a detection wheel (10) rotatably connected to the equipment mounting plate (39). An encoder (30) is provided on the back of the equipment mounting plate (39) and connected to the rear end of the detection wheel (10) for measuring the movement distance of the filter membrane.

5. The continuous monitor for radioactive aerosols as claimed in claim 3, wherein, The membrane recovery assembly comprises a second expansion shaft (4) rotatably connected with the equipment mounting plate (39), the second expansion shaft (4) is used for winding the recovered filter membrane, and a second baffle (3) is arranged on the second expansion shaft (4) and used for limiting the axial movement of the recovered filter membrane roll, and the back surface of the equipment mounting plate (39) is provided with a recovery motor (37) connected with the rear end of the second expansion shaft (4) and used for driving the second expansion shaft (4) to rotate.

6. The continuous monitor for radioactive aerosols as claimed in claim 3, wherein, The sampling unit (1) further comprises a sampling shell (68) arranged on the front plate surface of the equipment mounting plate (39), the drive assembly comprises a motor drive assembly fixedly mounted on the lower end of the sampling shell (68), the sampling shell (68) is provided with an axial bearing (70) in the middle, the piston (65) is connected with the inner ring of the axial bearing (70) and is limited to move vertically on the sampling shell (68) only, and the bottom of the piston (65) is in transmission connection with the output shaft of the motor drive assembly through a curve-to-straight module. The curve-to-straight module comprises a tubular shaft sleeve (69) connected with the output shaft of the motor drive assembly, the side wall of the shaft sleeve (69) is provided with a spiral groove (14), the lower end of the piston (65) extends into the shaft sleeve (69) and is provided with a positioning pin (15) extending into the spiral groove (14), and the piston (65) is driven to move vertically when the output shaft of the motor drive assembly rotates.

7. A continuous monitor for radioactive aerosols as claimed in claim 6, characterised in that, The piston (65) is embedded with a honeycomb net (64) in a sealing ring (63), and the top surface of the sealing ring (63) is higher than the honeycomb net (64).

8. The continuous monitor for radioactive aerosols as claimed in claim 6, wherein, The vertical groove distance of the spiral groove (14) is greater than the diameter of the positioning pin (15); further comprising a spring (67), the upper end of the spring (67) is in abutment with the bottom of the airflow chamber (2), and the lower end of the spring (67) is in abutment with the bearing surface of the sampling shell (68).

9. The continuous monitor for radioactive aerosols as claimed in claim 1, wherein, Further comprising a radioactive level analysis multi-channel module (41) mounted in the box (100), the radioactive level analysis multi-channel module (41) is signal connected with the detector (61) and is used for analyzing the nuclide amount and quality level of the aerosol.

10. The continuous monitor for radioactive aerosols as claimed in claim 3, wherein, The radioactive aerosol continuous monitoring instrument further comprises a measurement and control unit (32) signal connected with the air inlet assembly, the radiation measurement assembly, the filter membrane operation unit, the sampling unit and the air pump unit for controlling them; The equipment mounting plate (39) is further provided with a "one-key membrane replacement" key (16) and a membrane replacement indicator light (17) both signal connected with the measurement and control unit (32), the "one-key membrane replacement" key (16) is used for controlling the piston (65) to descend through the measurement and control unit (32) when preparing to manually replace the membrane, the measurement and control unit (32) controls the membrane replacement indicator light (17) to light up when descending to the stop point, and the measurement and control unit (32) controls the membrane replacement indicator light (17) to be turned off after the membrane replacement is completed.

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