Universal particle counter calibration device

Abstract

The utility model provides a general particle counter calibration device and a calibration method, the device comprises a first gas circuit, a second gas circuit and a third gas circuit, the three gas circuits are respectively connected with a blending box, the blending box is provided with a sampling outlet, and the sampling outlet is respectively connected with a standard particle counter and a calibrated particle counter; the first gas path comprises a first high-efficiency filter and an electromagnetic valve which are connected in sequence; the second gas path comprises a compressed air system and a first mass flow meter which are connected in sequence; the third gas path comprises a compressed air system, a second mass flow meter, an aerosol atomization device, a drying and dehumidifying device, an electrostatic neutralization device and a differential electromigration device which are connected in sequence; and the second gas path and the third gas path share one set of compressed air system and are used for obtaining clean compressed gas. The calibration device provided by the utility model can realize on-line calibration of small-flow, medium-flow and large-flow particles, and improves the stability of the whole generator source.

Description

TECHNICAL FIELD

[0001] The utility model relates to the granule counter calibration technical field, especially a kind of general particle counter calibration device and calibration method. BACKGROUND

[0002] Air particulate pollution is the main pollution source in the production and processing technology of pharmaceutical, electronic, aviation and other industries, such as in the electronic industry and chip manufacturing industry, the deposition of small particles in the gas can cause electrical bad characteristics and even greater damage, therefore, accurate assessment of air quality has become an urgent demand in production and product quality testing of these industries. Currently, the main commercial instrument for air cleanliness measurement is the particle counter. The working principle of the particle counter is that when the air containing dust particles passes through the light-sensitive area of the instrument, a light pulse signal proportional to the particle size is scattered. This signal is received by a light-sensitive device and converted into a corresponding electrical pulse signal, which is then amplified. By counting the electrical pulses within a detection period, the number of particles per unit volume of sampled air, i.e. the particle concentration, can be determined. The particle counter is a national measurement instrument. After a period of use, its optical system and detection system will change, such as light source aging, reduced light emission efficiency, or focusing misalignment, lens contamination, which will change the conversion sensitivity of the entire machine. The JJF1190-2008 Dust Particle Counter National Measurement Calibration Specification has been introduced, which requires periodic calibration of the particle counter and adjustment of various aspects of the instrument to achieve the best working state.

[0003] The current mainstream flow rate of general particle counters is 2.83 L / min and 28.3 L / min. According to the JJF1190-2008 Dust Particle Counter National Measurement Calibration Specification, it can be calibrated, but the calibration device and method cannot realize the traceability of the value for large flow particle counters. The current calibration device requires that the particle concentration after aerosol atomization be controlled within ±5% / 8h, and the repeatability of continuous particle concentration measurement be not greater than 5%. The stability of the aerosol generator source is insufficient, which can cause measurement uncertainty to be too large and affect the accuracy of the measurement results.

[0004] With the popularization and application of particle counting, there are different requirements for the measurement of flow, particle size and particle concentration of particle counters. For example, in the latest air cleanliness detection standard GB / T16292-2010 "Test method for suspended particles in clean room (area) of pharmaceutical industry", the minimum sampling volume is stipulated according to different cleanliness levels and particle size ranges, that is, the sampling volume of each sampling point shall not be less than 1 cubic meter, that is, 1000L. Therefore, in order to save sampling time and ensure the reliability of cleanliness monitoring results, a large flow dust particle counter (such as sampling flow 50L / min, 100L / min) is needed. For some application environments, some enterprises want to miniaturize the particle counter by reducing the size of the pump body and the light sensor, so that the entire device is more miniaturized, such as changing the flow of the particle counter to 0.3L / min, 1L / min, 1.67L / min or 2L / min, etc. Therefore, according to the use requirements of different particle counters, an effective particle counter calibration device is designed to improve the stability and accuracy of the calibration device source, and to meet the calibration requirements of different particle counters, which becomes an urgent problem to be solved.

[0005] The existing application number for 201910210333.X Chinese invention patent-dust particle counter calibration device and calibration method, its calibration device mainly uses passive air supplement, virtual cutting and other technologies, which can realize accurate calibration of (2.83-100)L / min dust particle counter, and needs negative pressure pump to use device, for small flow particle counter (less than 2.83L / min), cannot realize calibration.

[0006] Therefore, it is urgent to study a universal particle counter calibration device to realize the calibration of particle counters of all flow rates, and improve the accuracy and precision of instrument measurement. Practical new type content

[0007] The technical problem to be solved by the present application is to provide a universal particle counter calibration device to overcome the problem that the existing particle counter calibration device cannot meet the calibration of particle counters of all flow rates.

[0008] The present application is implemented as follows: a universal particle counter calibration device, the device comprises a first gas path, a second gas path and a third gas path, the three gas paths are connected with a mixing box respectively, the mixing box is provided with an input port and a sampling outlet, the sampling outlet is connected with a standard particle counter or a calibrated particle counter respectively;

[0009] The first gas path comprises a first high efficiency filter and an electromagnetic valve connected in sequence;

[0010] The second gas path comprises a compressed air system and a first mass flow meter connected in sequence;

[0011] The third air path includes a compressed air system, a second mass flow meter, an aerosol atomizing device, a drying and dehumidifying device, an electrostatic neutralization device, and a differential electromigration device connected in sequence.

[0012] The second and third air paths share a single compressed air system to obtain clean compressed gas;

[0013] Clean compressed air obtained through the third gas path is sent to the aerosol nebulizer, where polystyrene latex standard particles are atomized into monodisperse aerosols. After dehumidification and drying, the aerosols pass through an electrostatic neutralizer to achieve Boltzmann charge balance. The monodisperse aerosol samples are then sieved by a differential electromigration device to form narrow-peak monodisperse aerosols, which are then sent to the mixing chamber. After passing through the first high-efficiency filter of the first gas path to obtain clean gas, the aerosols pass through a solenoid valve into the mixing chamber for passive gas replenishment. Additionally, clean compressed air obtained through the second gas path is sent to the mixing chamber for active gas replenishment, thereby adjusting the flow rate and concentration required for particle counter calibration at different flow rates.

[0014] Furthermore, the compressed air system includes an air compressor, a refrigerated dryer, and a second high-efficiency filter connected in sequence, through which clean compressed gas is obtained.

[0015] Furthermore, the standard solution bottle in the aerosol atomizing device is connected to a return water bottle via a peristaltic pump, and a magnetic stirrer is installed at the bottom of the return water bottle.

[0016] Since the atomization process involves diluting a high-concentration standard substance into a low-concentration liquid—for example, in the preparation process, 0.1 mL of the standard substance is typically placed in 500 mL of pure water and thoroughly stirred—during atomization, due to the special design of the atomizer, high-pressure gas carries the particles of the solution out, while water molecules in the solution return to the solution. Over time, this causes a decrease in the concentration of atomized particles. This invention addresses this by designing two bottles: one for the original atomized standard concentrate and the other for the return water from the atomization device. A corresponding peristaltic pump is also included. When the standard solution bottle is empty, the concentrate from the return water bottle is drawn into the standard solution bottle, enabling a second measurement and thus improving the stability of the particle concentration during each measurement.

[0017] Furthermore, the mixing box includes a cylindrical box body and a conical bottom. The upper half and lower half of the cylindrical box body are threaded together. The upper half of the cylindrical box body is provided with an inlet for installing an input pipe. The input pipe is an L-shaped telescopic pipe, which consists of a horizontal section and multiple vertical sections. The corners between the horizontal and vertical sections are rounded.

[0018] The advantages of this invention are: by designing a universal particle counter calibration device, it can meet the calibration requirements of particle counters of different flow rates and models, such as online, low flow rate, medium flow rate, and high flow rate. It can achieve full-range calibration without setting up multiple particle counter calibration devices, while improving the overall stability of the generator source, making the stability better than 1%. Moreover, the cost of this calibration device is low. Attached Figure Description

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0020] Figure 1 This is a schematic diagram of the structure of a universal particle counter calibration device according to the present invention.

[0021] Figure 2 This is a schematic diagram of the connection structure between the standard bottle and the return water bottle of the aerosol atomizing device in a universal particle counter calibration device of this utility model.

[0022] Figure 3 This is a schematic diagram of the mixing box structure in a general particle counter calibration device of this utility model.

[0023] Figure 4 This is a schematic diagram of the calibration process using the device of this utility model in a specific embodiment.

[0024] Figure 5 This is a schematic diagram of the calibration process using the device of this utility model in another specific embodiment.

[0025] Explanation of icon numbers:

[0026] 1. Mixing box; 11. Inlet; 12. Sampling outlet; 13. Cylindrical box; 14. Conical bottom; 15. Inlet pipe; 151. Horizontal section; 152. Vertical section; 2. First high-efficiency filter; 3. Solenoid valve; 4. Compressed air system; 41. Air compressor; 42. Refrigerated dryer; 43. Second high-efficiency filter; 5. First mass flow meter; 6. Second mass flow meter; 7. Aerosol atomizing device; 71. Standard solution bottle; 72. Peristaltic pump; 73. Return water bottle; 74. Magnetic stirrer; 8. Drying and dehumidification device; 9. Electrostatic neutralization device; 10. Differential electromigration device; A. Standard particle counter; B. Particle counter to be calibrated. Detailed Implementation

[0027] This application provides a universal particle counter calibration device to solve the problem of limited flow rate during existing particle counter calibration, and enables efficient calibration of particle counters with different flow rates.

[0028] The overall concept of the technical solution in this application embodiment is as follows: This utility model designs three gas paths, including a passive gas replenishment path, an active gas replenishment path, and a main gas path. When calibration is required, different gas paths can be switched as needed to control the flow rate, so that one calibration device can meet the calibration needs of all existing flow particle counters on the market, while improving the concentration stability of the aerosol generator and improving the calibration accuracy.

[0029] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0030] like Figure 1 As shown, this embodiment provides a universal particle counter calibration device. The device includes a first gas path, a second gas path, and a third gas path. The three gas paths are respectively connected to a mixing chamber 1. The mixing chamber 1 is provided with an inlet 11 and a sampling outlet 12. The sampling outlet 12 is respectively connected to a standard particle counter A or a particle counter B to be calibrated, and excess gas is vented. If it is necessary to connect the standard particle counter A and the particle counter B to be calibrated at the same time, an aerosol splitter can be connected to the sampling outlet. The standard particle counter and the particle counter to be calibrated can be connected to the aerosol splitter respectively to achieve joint measurement at multiple sampling outlets. According to specific needs, the extra sampling ports of the aerosol splitter (using the existing four-sampling-port aerosol splitter) can be blocked.

[0031] The first air path includes a first high-efficiency filter 2 and a solenoid valve 3 connected in sequence;

[0032] The second air path includes a compressed air system 4 and a first mass flow meter 5 connected in sequence;

[0033] The third air path includes a compressed air system 4, a second mass flow meter 6, an aerosol atomizing device 7, a drying and dehumidifying device 8, an electrostatic neutralization device 9, and a differential electromigration device 10 connected in sequence; the drying and dehumidifying device 8 can be a single device or two devices: a drying device and a dehumidifying device.

[0034] The second and third air paths share a single compressed air system to obtain clean compressed gas;

[0035] Clean compressed air obtained through the third gas path is sent to the aerosol nebulizer 7, where polystyrene latex standard particles are atomized into monodisperse aerosols. After dehumidification and drying, the aerosols are then passed through the electrostatic neutralizer 9 to achieve Boltzmann charge balance. The monodisperse aerosol samples are then sieved through the differential electromigration device 10 to form narrow-peak monodisperse aerosols, which are then sent into the mixing chamber. After passing through the first high-efficiency filter 2 of the first gas path to obtain clean gas, the aerosols enter the mixing chamber 1 through the solenoid valve 3 for passive gas replenishment. Additionally, clean compressed air obtained through the second gas path is sent into the mixing chamber 1 for active gas replenishment, thereby adjusting the flow rate and concentration required for particle counter calibration at different flow rates.

[0036] Preferably, the compressed air system 4 includes an air compressor 41, a refrigerated dryer 42, and a second high-efficiency filter 43 connected in sequence. Air passes through the air compressor 41, the refrigerated dryer 42, and the second high-efficiency filter 43 to obtain clean compressed gas. Specifically, the air compressor generates high-pressure gas, the refrigerated dryer removes moisture from the compressed air, and the high-efficiency filter and mass flow meter produce clean compressed gas with constant flow and pressure. An aerosol atomization device atomizes aerosol standard samples in solution, producing peak particle sizes ≤2μm and a number concentration not less than (10^6). 3 ~10 5 The aerosol sample consists of 100 particles / L, with the standard sample being nationally certified monodisperse polystyrene latex microspheres. Treatment of the aerosol samples with a drying and dehumidification device and an electrostatic neutralizer effectively removes moisture and static electricity from the aerosol particles, preventing particle aggregation and enlargement.

[0037] Better, such as Figure 2 As shown, the standard solution bottle 71 in the aerosol atomizing device 7 is connected to a return water bottle 73 via a peristaltic pump 72. A magnetic stirrer 74 is installed at the bottom of the return water bottle 73. The return water bottle 73 receives atomized water molecules from the standard solution bottle and returns the solution in the return water bottle 73 to the standard solution bottle 71 via the peristaltic pump 72. The magnetic stirrer 74 also stirs the solution in the return water bottle 73 evenly. This stirring operation is mainly performed before the aerosol atomizing device is turned on for the second time and before the solution in the return water bottle 73 is returned to the standard solution bottle 71 to ensure that the reused solution is mixed evenly.

[0038] Better, such as Figure 3 As shown, the mixing box 1 includes a cylindrical box body 13 and a conical bottom 14. The upper half and lower half of the cylindrical box body 13 are threaded together. The upper half of the cylindrical box body 13 is provided with an input port for installing an input pipe 15. The input pipe 15 is an L-shaped telescopic pipe, which is composed of a horizontal section 151 and multiple vertical sections 152. The corners between the horizontal and vertical sections are arc-shaped.

[0039] Preferably, the first high-efficiency filter 2 is a 0.01 μm filter membrane.

[0040] The calibration process using the above-mentioned calibration device is as follows:

[0041] like Figure 4 As shown in one specific embodiment, the calibration method of a universal particle counter calibration device of the present invention includes:

[0042] Step S1: Adjust the input pipe of the mixing box to be positioned in the upper half of the mixing box;

[0043] Step S2: Determine the flow rate of the particle counter being calibrated. If it is greater than 50 L / min, i.e., a large flow rate particle counter, then execute step S3. If it is less than or equal to 2.83 L / min, then execute step S4. If it is between 2.83 L / min and 50 L / min, then select either step S3 or step S4 to execute.

[0044] Step S3: Close the first mass flow meter of the second gas path, start the solenoid valve of the first high-efficiency filter in the first gas path, and open the third gas path. Configure the concentration range and flow rate of the aerosol atomized particles, set the particle size of the differential electromigration aerosol, and the atomized particles pass through the mixing chamber. All the monodisperse aerosol particles are sucked into the particle counter. At the same time, clean gas is obtained from the first gas path and enters the mixing chamber to enter the calibration particle counter to maintain the dynamic balance between the gas in the mixing chamber and the particle counter gas path. The calibration particle counter records the measured value, and then the standard particle counter records the measured value in the same way to obtain the respective measured values. Proceed to step S5.

[0045] Specifically, the standard particles to be tested can be measured first. Due to the operation (evacuation) of the particle counter, a negative pressure is generated in the mixing chamber. Ambient air is drawn into the mixing chamber through the first high-efficiency filter, producing clean gas. This allows the pressure and flow rate in the mixing chamber to reach a dynamic balance. Due to the special design of the chamber, the supplemented clean gas envelops the original aerosol, forming a sheath gas protection, which helps protect the sensor of the particle counter being measured. For example, when the pump flow rate of the particle counter is 50 L / min and the aerosol atomization flow rate is 2 L / min, the remaining 48 L / min flow rate is automatically drawn into the mixing chamber by the first high-efficiency filter and enters the particle counter. Generally, the flow rate of the second mass flow meter is set to 2 L / min, and its range is (0-5) L / min.

[0046] Step S4: Close the solenoid valve of the first high-efficiency filter in the first gas path, start the first mass flow meter in the second gas path, and open the third gas path. Mix the high-concentration particles and clean compressed gas thoroughly in the mixing chamber, and measure the standard particle counter and the particle counter to be calibrated respectively to obtain their respective measurement values. The setting range of the first mass flow meter is (0~100) L / min. Different flow rates are set according to different measuring instruments and particle concentration requirements.

[0047] Step S5: Analyze and compare the obtained measurement values ​​using the unit volume particle concentration measurement comparison method to obtain the calibration results.

[0048] In step S2, the flow rates of the standard particle counter and the particle counter under test must be at the same level, for example, both 2.83 or both 28.3. If none are the same, two that are close to each other are selected for calibration.

[0049] The specific measurement process in step S4 is as follows:

[0050] The standard particle concentrate to be measured is placed into the aerosol atomizing device. The concentration range and flow rate of the aerosol atomized particles are set, the particle size of the differential electromigration aerosol is set, the solenoid valve of the first high-efficiency filter is closed, the first mass flow meter is opened, the corresponding flow rate value is set, and clean compressed gas of the corresponding flow rate flows in to dilute the concentration of the atomized particles, thereby obtaining the corresponding output flow rate, which is then output to the standard particle counter and the particle counter to be calibrated, respectively.

[0051] In step S4, during the measurement process, both the standard particle counter and the particle counter being calibrated are simultaneously connected to the calibration device for isokinetic sampling. For example, if the flow rate of the instrument being calibrated is 2.83 L / min and the flow rate of the standard particle counter is also 2.83 L / min, and the first mass flow meter is set to a range of 18 L / min and the second flow meter is set to 2 L / min, the original aerosol and the clean gas are mixed evenly in the mixing chamber, diluting the original aerosol concentration by 10 times. An aerosol splitter is connected to the end of the mixing chamber, with its two ports connected to the standard particle counter and the particle counter being tested, respectively, and any excess gas is vented.

[0052] Specifically, step S5 involves setting the particle counter to record the particle concentration value once per minute, denoted as C. Ti After 10 measurements, the average particle concentration from the 10 measurements is calculated and recorded as follows: Similarly, each measurement value of the standard particle counter is recorded as C. Si After 10 measurements, the average particle concentration of the 10 measurements was calculated. The number efficiency η of the particle counter under calibration at this particle size can be obtained using the following formula. C :

[0053]

[0054] In the formula:

[0055] η C —Particle counting efficiency, %, for aerosol samples with a particle size of D (i.e., the particle size of the currently used standard material) measured by the particle counter being calibrated;

[0056] η S —The particle counting efficiency of a standard particle counter for measuring aerosol samples with a particle size of D (i.e., the particle size of the currently used standard material), %.

[0057] The method further includes: selecting particles of different sizes for particle measurement, and measuring the repeatability of different particle sizes, as detailed below:

[0058] Two particle size standard materials are selected: one is a particle size standard material whose particle size lower limit is close to that of the particle counter being calibrated, and the other is a particle size standard material whose average particle size D is between 2 and 3.0 times the lower limit of the particle counter being calibrated, generally a 1.0 μm particle size standard material (e.g., standard particulate matter, certificate number GBW(E)120060, average particle size value is 1089 nm, uncertainty is 32 nm). Steps S2 to S4 are repeated to obtain various measurement values, and the particle counting repeatability of the particle counter being calibrated under different particle standard materials is calculated. The formula for calculating the particle counting repeatability is as follows:

[0059]

[0060] In the formula:

[0061] δ C — Repeatability of the standard particle counter under calibration, %;

[0062] n—number of measurements, n = 10.

[0063] like Figure 5 As shown, in another specific embodiment, the present invention provides a calibration method for a universal particle counter calibration device, the method comprising:

[0064] Step S1: Adjust the input pipe of the mixing box to be placed in the lower half of the mixing box;

[0065] Step S2: If the flow rate of the particle counter to be calibrated is greater than 50 L / min, i.e., the particle counter to be calibrated is a high-flow-rate particle counter, perform the following calibration operation: open the solenoid valve of the first high-efficiency filter in the first gas path, close the first mass flow meter in the second gas path, open the third gas path, configure the concentration range and flow rate of the aerosol atomized particles, set the particle size of the differential electromigration aerosol, send the atomized monodisperse aerosol particles into the mixing chamber, connect the particle counter to be calibrated and the standard particle counter to the mixing chamber in sequence for testing, continuously measure multiple times to obtain the corresponding measurement values, and use the measurement value comparison method of the total number of particles to analyze and compare the obtained measurement values ​​to obtain the calibration result.

[0066] Step S3: If the flow rate of the particle counter to be calibrated is 2.83 L / min to 50 L / min, i.e., the particle counter to be calibrated is a medium flow rate particle counter, perform the following calibration operation: close the solenoid valve of the first high-efficiency filter in the first gas path, start the first mass flow meter in the second gas path, open the third gas path, configure the concentration range and flow rate of the aerosol atomized particles, set the particle diameter of the differential electromigration aerosol, and let the atomized particles pass through the mixing chamber. Connect the particle counter to be calibrated and the standard particle counter to the mixing chamber in sequence for testing, and continuously measure multiple times to obtain the corresponding measurement values. Use the measurement value comparison method of the total number of particles to analyze and compare the obtained measurement values ​​to obtain the calibration result.

[0067] The specific method for comparing the measured total number of particles is as follows:

[0068] After the aerosol concentration stabilized, the standard particle counter and the particle counter under test were measured sequentially. Each particle counter was measured 10 times, with each measurement lasting 1 minute. The average values ​​were calculated and recorded as follows: and The number efficiency η of the particle counter under this particle size is calculated using the following formula. C :

[0069]

[0070] In the formula:

[0071] η C —Particle counting efficiency, % of aerosol samples with a particle diameter of D (i.e., the particle size of the currently used standard material) measured by the particle counter being calibrated;

[0072] η S —Standard particle counter measures the particle counting efficiency (%) of aerosol samples with a particle size of D (i.e., the particle size of the currently used standard material);

[0073] Q c —Flow rate of the particle counter being calibrated, in L / min;

[0074] Q s —Flow rate value of a standard particle counter, in L / min.

[0075] This invention can calibrate particle counters with different flow rates. For particle counters with large and medium flow rates, calibration can be performed using the particle concentration measurement comparison method and the total particle count measurement comparison method. For particle counters with small flow rates, calibration can be performed using the particle concentration measurement comparison method, thus achieving calibration of particle counters with all ranges. At the same time, the device can improve the overall concentration stability of the generator source by additional collection and treatment of backflow, making the stability better than 1% and improving the measurement accuracy. Moreover, the calibration device of this invention has low cost and is easy to implement.

[0076] While specific embodiments of the present invention have been described above, those skilled in the art should understand that the specific embodiments described are merely illustrative and not intended to limit the scope of the present invention. Equivalent modifications and variations made by those skilled in the art in accordance with the spirit of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A universal particle counter calibration device, characterized by: The device comprises a first air path, a second air path and a third air path, which are connected with a mixing box respectively, the mixing box is provided with an input port and a sampling outlet, the sampling outlet is connected with a standard particle counter or a calibrated particle counter; The first air path comprises a first high-efficiency filter and a solenoid valve connected in sequence; The second air path comprises a compressed air system and a first mass flow meter connected in sequence; The third air path comprises a compressed air system, a second mass flow meter, an aerosol atomization device, a drying and dehumidifying device, an electrostatic neutralization device and a differential electromigration device connected in sequence; The second air path and the third air path share a set of compressed air system for obtaining clean compressed gas; The obtained clean compressed air is sent into the aerosol atomizer through the third air path, the polystyrene latex standard particles in the atomizer are atomized into monodisperse aerosol, and then the monodisperse aerosol sample is screened by the differential electromigration device to become narrow-peak monodisperse aerosol after dehumidification, drying and electrostatic neutralization, and then the narrow-peak monodisperse aerosol is sent into the mixing box, the clean gas obtained after the first high-efficiency filter of the first air path is sent into the mixing box through the solenoid valve for passive air supplement, and the clean compressed air obtained through the second air path is sent into the mixing box for active air supplement, so as to adjust the flow rate and concentration required for particle counter calibration.

2. A universal particle counter calibration device as claimed in claim 1, characterized in that: The compressed air system comprises an air compressor, a cold dryer and a second high-efficiency filter connected in sequence, and clean compressed gas is obtained after the air passes through the air compressor, the cold dryer and the second high-efficiency filter.

3. A universal particle counter calibration device as in claim 1, wherein: The standard solution bottle in the aerosol atomization device is connected with a water return bottle through a peristaltic pump, and a magnetic stirrer is installed at the bottom of the water return bottle.

4. A universal particle counter calibration device as in claim 1, wherein: The mixing box comprises a cylindrical box body and a conical bottom, the upper half and the lower half of the cylindrical box body are threadedly connected, the upper half of the cylindrical box body is provided with an input port for installing an input pipeline, the input pipeline is an L-shaped telescopic pipeline, the L-shaped telescopic pipeline is composed of a horizontal section and multiple vertical sections, and the corners of the horizontal section and the vertical sections are in arc shape.

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